The invention relates to a radiofrequency power semiconductor module having a cavity housing constructed from three modules, a 1st module, which has an upwardly and downwardly open housing frame with horizontally arranged flat conductors, a 2nd module, which has the chip island as a heat sink with at least one radiofrequency semiconductor component, the 2nd module forming the bottom of the cavity housing, and a 3rd module, which has the housing cover.

On account of the high evolution of heat and the radiofrequency properties, radiofrequency power semiconductor modules are accommodated in cavity housings made of ceramic. Moreover, it is possible to construct high-power modules which are packaged completely in plastics composition and whose radiofrequency semiconductor components are arranged on a chip island, at least one surface of which forms an outer wall of the housing that can be cooled by the surroundings. However, the use of such high-power modules for radiofrequency applications is limited on account of the dielectric properties of the plastic housing composition into which the radiofrequency semiconductor components are embedded.
The flat conductor frames required for devices of this type are constructed in extremely complex fashion since, on the one hand, they have to afford a first plane for free-standing flat conductors and, on the other hand, they have to afford a second plane with a solid metallic chip island for dissipating the heat. The technical outlay and outlay on costs for flat conductor frames of this type is of a similar magnitude to that for ceramic cavity housings. However, the heat dissipation of ceramic cavity housings is not particularly effective. Moreover, both housing forms have the disadvantage that the seating or the fixing of the radiofrequency semiconductor component can only be successfully tested when the radiofrequency semiconductor components are accommodated and wired in the relatively expensive housing forms, so that functional and quality tests can only be used relatively late for the known housing forms.
Therefore, it is an object of the present invention to specify a radiofrequency power semiconductor module which overcomes the disadvantages in the prior art and can be produced inexpensively with a reduced failure rate.
This object is achieved by means of the subject matter of the independent claims. Advantageous developments of the invention emerge from the subclaims.
The invention specifies a radiofrequency power semiconductor module having a cavity housing and at least one radiofrequency semiconductor component arranged in the cavity housing. Moreover, the cavity housing has a chip island, on which the radiofrequency semiconductor components are arranged. Furthermore flat conductors are anchored in a housing frame closed off by a housing cover. This radiofrequency power semiconductor module has three prefabricated modules, a 1st module having flat conductors arranged horizontally in the upwardly and downwardly open housing frame. A 2nd module has the chip island as a heat sink with at least one radiofrequency semiconductor component and forms the bottom of the cavity housing. The 3rd module closes up the cavity housing toward the top and has the housing cover.
A radiofrequency power semiconductor module of this type which is composed of three modules has the advantage that each module can inherently be tested in respect of its quality and functionality before the three modules are assembled to form an electronic device. What is particularly advantageous in this case is that the radiofrequency semiconductor component can already be positioned on a heat sink that replaces the previous chip island of a flat conductor frame. Consequently, the chip island can be produced completely independently of a flat conductor frame with simple means and forms the bottom of the cavity housing, which constitutes a lowering of the production costs since there is no need to provide complex flat conductor frames having, in two separate planes, on the one hand flat conductors and on the other hand a chip island that can be cooled externally. Such a complex construction of a three-dimensional flat conductor frame for realizing a radiofrequency power semiconductor module with a cooled chip island can consequently be avoided.
Moreover, it is possible to qualitatively and functionally check the secure anchoring of the radiofrequency semiconductor components on the chip island, furthermore the electrical contact between the radiofrequency semiconductor components and the chip island and the positioning of the radiofrequency semiconductor components on the chip island before the 2nd module is assembled with the 1st module. This advantage becomes particularly apparent when a plurality of radiofrequency semiconductor components are to be accommodated on the heat-dissipating chip island.
A further advantage of the radiofrequency power semiconductor module according to the invention is that the housing frame with flat conductors anchored therein can be produced as an independent module in mass production and it is possible to check the dimensional accuracy and precision of the housing frame in conjunction with the flat conductors anchored therein prior to assembly with the 2nd module. Consequently, the probability of only functional 1st modules being mechanically connected to functional 2nd modules to form an upwardly open cavity housing is improved and the failure rate after the connection of the flat conductors in the interior of the cavity housing to the electrodes of the radiofrequency semiconductor components is reduced.
In this respect, it should be noted that radiofrequency power semiconductor modules are to be realized by connecting hundreds of bonding wires in parallel on a flat conductor end to a corresponding electrode of a radiofrequency power semiconductor, so that it is advantageous if it is possible to carry out such cost-intensive production steps such as bonding with pretested 1st and 2nd modules of a radiofrequency power semiconductor module, whereby costs and reject rate can be considerably reduced.
In one embodiment of the invention, the housing frame may be produced from a plastic housing composition. The plastic material of this plastic housing composition may correspond to the plastic housing composition that is used for complete packaging of radiofrequency semiconductor components on a flat conductor frame. In the case of the present invention, it is possible to produce the housing frame on the flat conductor frame independently of the production of the 2nd module and thus independently of the fixing of the radiofrequency semiconductor components on a chip island. The same applies to the production of a housing frame made of a ceramic composition. The use of ceramic as housing frame has the advantage of improved dielectric properties compared with the plastic housing frame. However, the production of a ceramic housing frame is associated with higher costs compared with the production of a plastic housing frame.
The housing frame may be one of a plurality of housing frames arranged on a flat conductor frame. In this case, exclusively inner flat conductor ends—arranged in one plane—of each device position of the flat conductor frame are embedded in the housing frame. The flat conductor frame is of uncomplicated construction in this respect since the provision of a chip island is completely obviated for the realization of the 1st module. The housing frame merely anchors the inner flat conductor ends in a plastic housing composition or in a ceramic composition. In this case, the inner flat conductor ends may partly be kept free of housing frame material and have refined surfaces as bonding fingers. Such refined surfaces may have nickel, gold, silver or alloys thereof in order to facilitate a reliable bonding of gold bonding wires on these uncovered flat conductor ends in the housing frame.
The downwardly and upwardly open housing frame may widen in stepped fashion from bottom to top. This stepped extension makes it possible to provide a relatively large opening for the housing cover and to provide a correspondingly reduced opening for the housing bottom in the form of the chip island as heat sink. The enlarged opening for the housing cover has the advantage that a larger access opening is available for wiring the radiofrequency semiconductor components of the 2nd module with the bonding fingers of the 1st module, said access opening facilitating bonding from above.
The stepped formation of the housing frame from bottom to top may be configured in such a way that the housing frame has a lower attachment, with which the 2nd component can be brought into engagement or is in engagement. At the same time, the inner flat conductor ends can also be arranged on this lower attachment of the housing frame, the inner housing wall being set back relative to the opening for the 2nd component, so that a portion of the inner flat conductor ends remains free of housing frame material, so that these inner flat conductor ends that remain free can be accessed during bonding.
An upper attachment of the upwardly open housing frame formed in stepped fashion is suitable for receiving the 3rd component as housing cover. The 3rd component can thus be brought into engagement with said upper attachment. With this 3rd component, the radiofrequency power semiconductor module is completed and, in particular, the cavity housing is perfect. In an inexpensive version, the housing cover may comprise a plastic plate, but housing covers also based on ceramic and/or based on metal are preferred since they permit greater power losses for the radiofrequency semiconductor components that are to be arranged in the cavity housing. Moreover, the dielectric properties of a ceramic cover are more favorable than those of a plastic cover as housing covering. A metallic cover in turn shields the radiofrequency power semiconductor module from electromagnetic interference sources.
In a further embodiment of the invention, the 2nd component has a metal base, which projects from a metallic baseplate and can be brought into engagement with the lower attachment of the housing frame. Such a metal base may be formed in one piece with the metallic baseplate by electrodepositing the metal base on the baseplate or machining the baseplate on its top side in such a way that a metal base projects. Such a metal base has the advantage that the respective radiofrequency semiconductor component arranged on the metal base can be positioned exactly in relation to the housing frame. For this purpose, the base may have a height which, together with the thickness of the radiofrequency semiconductor components, approximately has the height level like the surfaces of the inner flat conductor ends on the lower attachment of the housing frame, which may have a bondable coating. Such dimensioning of the metal base has the advantage that the bonding connections can be arranged in a single plane, which facilitates the bonding operation per se and precludes fault sources.
In a preferred refinement, the radiofrequency power semiconductor module according to the invention is a radiofrequency power amplifier (RF power amplifier), in particular for mobile radio base stations.
The radiofrequency semiconductor components arranged on the metal base then typically have a plurality of radiofrequency power semiconductor components, in particular so-called RF-LDMOS transistors. Furthermore, an input diode and an output diode may be provided in order to protect the radiofrequency power amplifier against overvoltage.
Moreover, a plurality of the radiofrequency semiconductor components may be integrated circuits (ICs) in order to pass the high currents of the radiofrequency power semiconductor components to the flat conductors and conversely to take them up from the flat conductors, the radiofrequency power semiconductor module has hundreds of bonding wires in parallel from the inner flat conductor ends to the electrodes of the radiofrequency semiconductor components. These hundreds of bonding wires in practice form a flat cable with which the inner flat conductor ends are connected to the respective electrodes of the radiofrequency semiconductor components.
The three modules of the radiofrequency power semiconductor module may be connected to one another by means of adhesive layers or adhesive films. For this purpose, the adhesive may be applied to the respective boundary areas or joining areas of the individual modules before and after the latter are joined together to form an electronic device.
A method for producing a radiofrequency power semiconductor module has the following method steps:
Firstly, a 1st module is produced. This 1st module comprises an upwardly and downwardly open housing frame with embedded inner flat conductor ends. Flat, conductors project outward from the housing frame.
A 2nd module may be produced in parallel, said 2nd module having a metal base on a metal plate. At least one radiofrequency semiconductor component is arranged on the metal base, it being possible to fit the metal base into the downwardly open housing frame.
In parallel with the production of the 1st and 2nd modules, the 3rd modules may already be produced in the form of housing covers which can be fitted into the upwardly open housing frame. After the production of the three modules, functional and quality tests of these three individual modules are carried out. Afterward, firstly the 1st and 2nd modules are assembled by adhesively bonding the metal base of the 2nd module into the upwardly open housing frame of the 1st module. After assembly, the inner flat conductors of the 1st module can be connected to electrodes of the radiofrequency semiconductor components of the 2nd module via the upper opening of the housing frame.
Finally, the upwardly open housing frame can be completed with the 3rd module to form a cavity housing. This method of modular design has the advantage that each module can inherently be tested in respect of its function and its quality before the cost-intensive step of connecting the inner flat conductor ends to the electrodes of radiofrequency semiconductor components is carried out. On account of the power consumption of the radiofrequency semiconductor components, in the case of this connection hundreds of bonding wires are fitted in parallel on one of the inner flat conductors and placed onto one of the common electrodes of the radiofrequency semiconductor components.
In the case of radiofrequency power semiconductor modules, in particular, this method has the particular advantage that only such modules which have no functional and quality deficiencies whatsoever are assembled to form an electronic device. This drastically reduces the rejects in the production of radiofrequency power semiconductor modules.
In addition, it is possible to use a simplified flat conductor frame since this flat conductor frame only has to comprise free-standing flat conductors and does not have to have an integrally arranged chip island.
In detail, in order to produce a 1st module, a flat conductor frame with a multiplicity of device positions may be produced, flat conductors with free-standing flat conductor ends being arranged in one plane in each of the device positions and a downwardly and upwardly open housing frame being fitted in each of the device positions, the inner flat conductor ends being embedded in the housing frames, while the flat conductors project from the housing frame. Such a continuous strip comprising a flat conductor frame with a multiplicity of device positions and housing frames arranged thereon can easily be tested with regard to its quality and functionality, housing frames whose dimensions do not correspond to the requirements for frictionless assembly with the other modules being able to be marked and separated by sorting before cost-intensive method steps for producing the radiofrequency power semiconductor module are to be carried out.
The free-standing flat conductor ends to be incorporated into the housing frame may also be refined with a bondable coating on the flat conductor frame. Such bondable coatings may have nickel, gold, silver or alloys thereof. An essential feature of the quality control is, after the application of the housing frame, whether the bondable coating of the inner flat conductor ends is freely accessible or whether material of the housing frame covers parts of said bondable coating, so that the reliable bonding is not assured. Housings with faults of this type can be separated by sorting prior to the assembly of the 1st and 2nd modules.
The molding of the housing frame may be effected by means of injection-molding of a plastic housing composition. For this purpose, the flat conductor frame is inserted into an adapted injection mold and the free-standing inner flat conductor ends are embedded into the plastic housing composition in each of the device positions. Since the injection-molding of plastic housing compositions can be carried out relatively cost-effectively, it is possible to provide a flat conductor frame which has a housing frame made of plastic in each device position after the injection-molding.
If the housing frame is intended to comprise a ceramic material, then firstly a green body is molded by compression molding in each device position, the free-standing inner flat conductor ends being embedded into the green body, formed as a housing frame. The flat conductor frame with the molded-in green body as housing frame then passes through a sintering furnace, in which this green body material is sintered to form a ceramic housing frame. Although this process is more complicated than the injection-molding of plastic housing compositions, a ceramic housing frame affords dielectric advantages over a plastic housing frame. In this case of the ceramic housing frame, too, it is subsequently possible after sintering to carry out a quality and functional testing in the course of which unsuitable housing frames are marked on the flat conductor frame, so that no further modules of the cavity housing are connected to these marked flat conductor frames.
In order to produce the 2nd module, firstly metal plates with a base adapted to the downwardly open housing frame are produced. Afterward, at least one radiofrequency semiconductor component is arranged on each of the bases and its function and connection to the base are tested. In this case, unsuitable 2nd modules can be separated by sorting. This production method and test method ensure that only qualitatively and functionally high-quality 2nd modules are connected to 1st modules of the cavity housing.
Before the 1st and 2nd modules are joined together, the 1st module may be provided with an adapted adhesive film on the underside of the housing frame. An adhesive film may also be provided for joining together the 1st and 3rd modules. The use of adhesive films has the advantage that a correspondingly structured strip of adhesive film can be used for a plurality of housing frames on a strip-type flat conductor frame, which reduces the production costs.
After the 1st and 2nd modules are joined together, the inner flat conductor ends of the 1st module are connected to electrodes of the radiofrequency semiconductor components of the 2nd module by multiple parallel bonding of hundreds of bonding wires. In this case, the cavity housing remains upwardly open and it is only in the last method step that then, given successful bonding, the 3rd module in the form of a housing cover as termination is adhesively bonded onto the cavity housing by means of an adhesive layer or an adhesive film. In this case, said housing cover may be produced from plastic or from metal or else ceramic. The choice of material of the housing cover essentially depends on the radiofrequency use and the power range of the radiofrequency semiconductor components arranged on the chip island with a heat sink. While the cavity housing can advantageously be shielded against electromagnetic waves and interference sources with a metal cover, a ceramic cover is distinguished by its better dielectric properties compared with a plastic cover.
To summarize, it should be emphasized that a distinction can be made between the following radiofrequency power housings:    1. Cavity ceramic housings, permitting a high frequency range. These housings have a stable heat sink made of copper-tungsten (CuW) or similar alloys onto which the radiofrequency semiconductor components are soldered or alloyed. This alloying-on process is carried out at temperatures of between 300 and 450° C. A ceramic lamina is mounted peripherally around the soldered-on radiofrequency semiconductor components, flat conductor connections made of metal being mounted on said lamina in a manner insulated from the heat sink. Such a circuit carrier for radiofrequency power semiconductor components is supplied in preassembled form by a supplier. A housing concept of this type has the disadvantage of high costs and a high outlay since individual device handling and fabrication are required. However, the ceramic results in high thermal stability of the cavity housing and enables the devices to be operated in a frequency range greater than 3 GHz.    2. Another variant of a radiofrequency power module housing comprises a plastic housing injection-molded all around with an exposed heat sink. However, such a housing with a plastic housing injection-molded around can be used only up to frequencies of approximately 1 GHz. Consequently, such plastic housings injection-molded all around cannot be used for GSM and UMTS applications. The low limiting frequency is attributable to the capsulation of the bonding wires with plastic housing composition and to the large dimensions between the radiofrequency semiconductor components and the external connections, which is realized by bonding wires of corresponding length. Consequently, although this type of housing has favorable production costs since composite fabrication is possible, the limiting frequency for the radiofrequency power devices at 1 GHz is extremely low.    3. It is also possible to use plastic cavity housings with an integrated heat sink. The frequency ranges are thereby slightly increased, but the limiting frequency range can only be increased by a factor of 2.5 to 2.5 GHz. The pre-injection-molded plastic cavity housings with an integrated heat sink have the advantage of favorable production costs, but sealing webs become necessary during the injection-molding of the housing, so that it is not possible to optimize the dimensions between the chip position and the inner flat conductors. By contrast, the invention has the following advantages:            1. favorable material and production costs        2. composite fabrication is possible        3. a frequency range greater than 2.5 GHz can be realized and        4. the use of soldering and alloying processes, in particular when applying the chip to the 2nd module, ensures lower thermal resistances for high-power applications. By way of example, a power loss during continuous operation of 240 W can thereby be realized.
The separate supply of the heat sink which, unlike hitherto, is not connected to the flat conductor frame enables the radiofrequency semiconductor components to be soldered or alloyed on the chip island at extremely high temperatures since the 2nd module can be produced completely separately from the housing frame with the flat conductor frame. Only afterward is the thermal conduction block including the radiofrequency semiconductor components inserted into the cavity housing whilst complying with narrow tolerances of the chips with respect to the inner flat conductor ends. Consequently, the advantages of different technologies can be brought together by means of the present invention to yield a housing product that can be produced cost-effectively and significantly more reliably.

Radiofrequency power semiconductor module with cavity housing, and method for producing it


A latch structure is adapted for covering a socket of an electronic apparatus. The latch structure includes a body and a slider. The body includes a covering portion and a fixing portion, and the covering portion includes at least one first sliding part. The fixing portion is flexibly connected to the covering portion and is fixed to the electronic apparatus. The slider is detachably assembled to the body. The slider includes at least one second sliding part, and the second sliding part corresponds to the first sliding part. When the covering portion is bent relative to the fixing portion and covers the socket, the slider is capable of moving relative to the covering portion to a fixed location, so that the location where the covering portion covers the socket is fixed.

1. Field of the Invention
The invention relates to a latch structure, and more particularly to a latch structure equipped with a slider.
2. Description of Related Art
The continuous research and innovation of computer-related technologies contribute to the persistent progress in the development of notebook computers as well as peripherals of notebook computers. In addition, the notebook computers have been applied to a great extent, e.g., for personal use, industrial use, and even military use. Hence, various inventions pertinent to notebook computers have been developed in response to the diversity of the applications of the notebook computers. For instance, the military notebook computers are required to be waterproof for all-weather use. Besides, when a user inadvertently spills water over a normal notebook computer, the water may permeate into the notebook computer through external sockets and damage the internal circuits; thereby, the notebook computer may malfunction.
To prevent moisture or foreign objects from entering the notebook computer through the external sockets, the waterproof structure of the notebook computer often includes latch structures to cover the external sockets, and these latch structures are often assembled to the sockets by way of interference. However, such assembly often appears to have unfavorable reliability. For instance, in case that a notebook computer falls down, the latch structures therein are apt to fall off from the computer. If a fixing structure (e.g., a locking member) is employed to secure the latch structures, the reliability of the notebook computer may be improved, whereas the assembly difficulty and the manufacturing costs may be correspondingly increased.


A method performed by a node includes writing normal records to a buffer. Each normal record is associated with a respective time interval having a respective start time and end time according to network time, and each normal record includes respective collected data describing an activity. The method includes detecting that access to network time has become unavailable as well as detecting that access to network time has become available after having been unavailable. The method includes determining information describing an incomplete period during which network time was unavailable, where the incomplete period includes at least one of a skipped interval and a standby interval. During each skipped interval, no collected data describing the activity is collected. Each standby interval is associated with respective collected data describing the activity during the incomplete period. The method includes writing to the buffer a placeholder record including the information describing the incomplete period.

A utility meter measures consumption of a resource. The resulting consumption data, which describes consumption of the resource, is stored on the utility meter at least temporarily. From time to time, the utility meter transmits data packets including the consumption data, either directly or indirectly, to a headend system of a service provider. The service provider uses the consumption data, for example, to bill a customer based on actual consumption of the resource.
Typically, consumption data is collected in fixed-length time intervals (e.g., fifteen-minute intervals), such that consumption data collected by the utility meter during a specific time interval (e.g., 9:00 am to 9:15 am on a given date) is stored on the utility meter in a record associated with that specific time interval. Thus, the utility meter maintains a set of records, each representing a time interval of an established length and each ideally associated with a respective start time. There typically exists a pre-established protocol for the transmission of consumption data, such that a data packet that includes the consumption data adheres to a specific format. For instance, a data packet includes consumption data for a set of time intervals, where each such time interval is associated with collected data. The data packet indicates the start time of the set of time intervals, and thus, given that the time intervals are consecutive, the start time for each time interval in the data packet can be inferred based on the start time of the entire set of time intervals.
A utility meter may not always maintain precise time internally, and this is particularly the case for battery-powered utility meters. For instance, although a utility meter may maintain an internal time, that internal time may drift from network time when the utility meter goes to sleep for the purpose of saving battery power or for another purpose. For another example, if the utility meter temporarily loses its network connection, the internal time of the utility meter may drift away from the network time. However, the utility meter is typically part of a network, and thus, the utility meter can utilize network time, maintained by the network, to ensure that each record of consumption data represents a time interval that is properly aligned with the start of an established time interval (i.e., time-aligned). From time to time, however, a utility meter may lose its network connection and may therefore lose network time. Although the utility meter can still collect consumption data and can still count out the length of a time interval via an internal counter, the utility meter is unable to associate the consumption data with an accurate start time. In part, this is because, if the utility meter lost power, the utility meter does not know how many time intervals have passed while the utility meter did not have power, which would lead to lost time and inability to assume that internal time-keeping is aligned with the network time.
To handle this case, two buffers are typically used. Records associated with respective start times, referred to herein as normal records, are written to a main buffer, and records representing standby intervals, referred to herein as standby records, are written to a temporary buffer. Because specific start times are not known for standby intervals, records of consumption data associated with standby intervals are typically not written directly into the main buffer. However, after network time becomes available, a start time can be established for each standby interval. Upon receiving network time, the main buffer of the utility meter is padded with zeroes, forming empty records, to represent skipped time intervals during which consumption data was not collected. At a position representing the established start time of standby records, each standby record is copied from the temporary buffer into the main buffer. The result is that the main buffer eventually includes normal records, standby records, and empty records, and each such record is eventually associated with a respective start time.

Sequential storage of collected data from heterogeneous intervals


The invention provides a semiconductor device having a transistor that can supply a proper current to a load (EL pixel and signal line) without being influenced by variations. A voltage of each terminal of a transistor is controlled by a feedback circuit using an amplifier circuit. A current Idata is inputted from a current source circuit to the transistor, and the feedback circuit sets a gate-source voltage that the transistor requires for supplying the current Idata. The feedback circuit controls the transistor to operate in a saturation region. Then, a gate voltage required for supplying the current Idata is set. When using the transistor set in this manner, a proper current can be supplied to a load (EL pixel and signal line). Note that a required gate voltage can be set quickly because of an amplifier circuit.

In recent years, a so-called self-luminous type display device that includes a pixel formed of a light emitting element such as a light emitting diode (LED) attracts attention. As a light emitting element used for such a self-luminous type display device, an organic light emitting diode (OLED), an organic EL element, or an electro luminescence (EL) element attracts attention and has been used for an organic EL display and the like.
Since a light emitting element such as an OLED is self-luminous type, it has the advantages of a higher visibility of a pixel than a liquid crystal display, a fast response without a need of backlight, and the like. Further, the luminance of a light emitting element can be controlled by current.
As a driving method of a display device using such a self-luminous type light emitting element, a passive matrix method and an active matrix method are known. The former has problems such as difficulty in realizing a large and high luminance display, though its simple structure. Therefore, in recent years, the active matrix method has been actively developed, in which a current flowing to a light emitting element is controlled by a thin film transistor (TFT) provided in a pixel circuit.
In the case of a display device adopting such an active matrix method, there are problems in that a current flowing to a light emitting element changes due to variations in current characteristics of driving TFTs and variations in luminance are caused.
That is, in the case of a display device adopting the active matrix method, driving TFTs for driving a current flowing to light emitting elements are used in a pixel circuit, and there are problems in that a current flowing to the light emitting elements changes due to variations in characteristics of these driving TFTs and variations in luminance are caused. Thus, suggested are various circuits for suppressing variations in luminance, in which a current flowing to light emitting elements does not change even when characteristics of driving TFTs in a pixel circuit vary.
(Patent Document 1)
Published Japanese Translation of PCT International Publication for Patent Application No. 2002-517806
(Patent Document 2)
International Publication WO 01/06484
(Patent Document 3)
Published Japanese Translation of PCT International Publication for Patent Application No. 2002-514320
(Patent Document 4)
International Publication WO 02/39420
A configuration of an active matrix display device is disclosed in Patent Documents 1 to 4. Disclosed in Patent Documents 1 to 3 is a circuit configuration in which a current flowing to light emitting elements does not change due to variations in characteristics of driving TFTs disposed in a pixel circuit. This configuration is called a current writing pixel or a current input pixel. Meanwhile, disclosed in Patent Document 4 is a circuit configuration for suppressing changes in signal current due to variations in TFTs in a source driver circuit.
FIG. 6 shows a first configuration example of an existing active matrix display device disclosed in Patent Document 1. A pixel shown in FIG. 6 comprises a source signal line 601, first to third gate signal lines 602 to 604, a current supply line 605, TFTs 606 to 609, a storage capacitor 610, an EL element 611, and an image signal inputting current source 612.
A gate electrode of the TFT 606 is connected to the first gate signal line 602, a first electrode thereof being connected to the source signal line 601 and a second electrode thereof being connected to a first electrode of the TFT 607, a first electrode of the TFT 608 and a first electrode of the TFF 609. A gate electrode of the TFT 607 is connected to the second gate signal line 603, a second electrode thereof being connected to a gate electrode of the TFT 608. A second electrode of the TFT 608 is connected to the current supply line 605. A gate electrode of the TFT 609 is connected to the third gate signal line 604, a second electrode thereof being connected to an anode of the EL element 611. The storage capacitor 610 is connected between the gate electrode of the TFT 608 and the current supply line, and holds a gate-source voltage of the TFT 608. The current supply line 605 and a cathode of the EL element 611 are inputted with respective predetermined potentials and have a potential difference therebetween.
Operations from writing of a signal current to light emission are described with reference to FIG. 7. Each component in the drawings is denoted by the same reference numeral as FIG. 6. FIGS. 7A to 7C are schematic diagrams each showing a current flow. FIG. 7D shows a relationship between currents flowing in each path in writing a signal current. FIG. 7E shows a voltage that is held in the storage capacitor 610 in writing a signal current also, namely the gate-source voltage of the TFT 608.
First, a pulse is inputted to the first gate signal line 602 and the second gate signal line 603, and the TFTs 606 and 607 are turned on. A current flowing in the source signal line at this time, namely a signal current is referred to as Idata.
Since the current Idata flows in the source signal line, a current flows in a pixel through current paths I1 and 12 as shown in FIG. 7A. The relationship between the divided currents is shown in FIG. 7D. It is needless to say that Idata=I1+I2 is satisfied.
At the moment when the TFT 606 is turned on, electric charges are not held in the storage capacitor 610 yet, thus the TFT 608 is off. Accordingly, I2 is equal to 0 whereas Idata is equal to I1. That is, during this period, current flows only in accordance with electric charges accumulated in the storage capacitor 610.
Then, electric charges are slowly accumulated in the storage capacitor 610, and thereby a potential difference begins to occur between both electrodes (FIG. 7E). When a potential difference between both electrodes being equal to Vth (FIG. 7E, point A), the TFT 608 is turned on and I2 is generated. Since Idata=I1+I2 is satisfied as described above, I1 gradually decreases, though current flows yet and electric charges are accumulated in the storage capacitor.
In the storage capacitor 610, electric charges continue to be accumulated until a potential difference between both electrodes thereof, that is, the gate-source voltage of the TFT 608 becomes equal to a desired voltage, namely a voltage (VGS) that allows the TFT 608 to supply the current Idata. When the accumulation of electric charges is completed (FIG. 7E, point B), the current I1 stops flowing, the TFT 608 supplies a current corresponding to the VGS at this time, and thereby Idata becomes equal to I2 (FIG. 7B). Thus, the steady state is reached. That is the end of the writing operation of signals. Finally, the selection of the first gate signal line 602 and the second gate signal line 603 is completed and the TFTs 606 and 607 are turned off.
Subsequently, a light emitting operation starts. A pulse is inputted to the third gate signal line 604 and the TFT 609 is turned on. Since the storage capacitor 610 holds the VGS that has been written earlier, the TFT 608 is on and the current Idata is supplied from the current supply line 605. Accordingly, the EL element 611 emits light. When the TFT 608 is set to operate in a saturation region at this time, the current Idata can flow without changes even when a source-drain of the TFT 608 voltage varies.
Such an operation that outputs a set current is called an output operation herein. The current writing pixel shown above as an example has the advantages that even when there are variations in characteristics of the TFT 608 and the like, the storage capacitor 610 holds a gate-source voltage required for flowing the current Idata, a desired current can be supplied to the EL element with accuracy, and thereby variations in luminance due to variations in characteristics of TFTs can be suppressed.
Described above is an example for correcting changes in current due to variations of driving TFTs in a pixel circuit. The same problem occurs in a source driver circuit. Disclosed in Patent Document 4 is a circuit configuration for preventing changes in signal current due to production variations of TFTs in a source driver circuit.

Semiconductor device including a pixel having current-driven light emitting element

Semiconductor Energy Laboratory Co., Ltd.


Objects of the present invention are the compounds of formula I

Protein kinases ("PKs") are enzymes that catalyze the phosphorylation of hydroxy groups on tyrosine, serine and threonine residues of proteins (Hunter, T., Cell 50 (1987) 823-829). The consequences of this seemingly simple activity are staggering; cell growth, differentiation and proliferation, i.e., virtually all aspects of cell life in one way or another depend on PK activity. Furthermore, abnormal PK activity has been related to a hose of disorders, ranging from relatively non-life threatening diseases such as psoriasis to extremely virulent diseases such as glioblastoma (brain cancer).
The PKs can be conveniently broken down into two classes, the protein tyrosine kinases (PTKs) and the serine-threonine kinases (STKs).
One of the prime aspects of PTK activity is their involvement with growth factor receptors. Growth factor receptors are cell surface proteins. When bound by a growth factor ligand, growth factor receptors are converted to an active form which interacts with proteins on the inner surface of a cell membrane. This leads to phosphorylation on tyrosine residues of the receptor and other proteins and to the formation inside the cell of complexes with a variety of cytoplasmic signaling molecules that, in turn, effect numerous cellular responses such as cell division (proliferation), cell differentiation, cell growth, expression of metabolic effects to the extracellular microenvironment, etc. For a more complete discussion, see Schlessinger, J., and Ullrich, A., Neuron, 9 (1992, 383-391, which is incorporated by reference, including any drawings, as if fully set forth herein.
Growth factor receptors with PTK activity are known as receptor tyrosine kinases ("RTKs"). They comprise a large family of transmembrane receptors with diverse biological activity. At present, at least nineteen (19) distinct subfamilies of RTKs have been identified. An example of these is the subfamily designated the "HER" RTKs, which include EGFR (epidermal growth factor receptor), HER2 (human epidermal growth factor receptor 2), HER3 and HER4. These RTKs consist of an extracellular glycosylated ligand binding domain, a transmembrane domain and an intracellular cytoplasmic catalytic domain that can phosphoiylate tyrosine residues on proteins.
Another RTK subfamily consists of insulin receptor (IR), insulin like growth factor I receptor (IGF-IR) and insulin receptor related receptor (IRR). IR and IGF-IR interact with insulin, IGF-I and IGF-II to form a heterotetramer of two entirely extracellular glycosylated α subunits and two β subunits which cross the cell membrane and which contain the tyrosine kinase domain.
Another RTK subfamily is referred to as the platelet derived growth factor receptor ("PDGFR") group, which includes PDGFR alpha, PDGFR beta, colony-stimulating factor I receptor (CSF-IR), c-kit and flt 3. These receptors consist of glycosylated extracellular domains composed of 5 immunoglobin-like loops and an intracellular domain wherein the tyrosine kinase domain is interrupted by a kinase inert domain.
Another group which, because of its similarity to the PDGFR subfamily, is sometimes subsumed into the latter group is the fetal liver kinase ("Flk") receptor subfamily. This group, containing extracellulos immunoglobulin loops made up of kinase insert domain-receptor fetal liver kinase-1 (KDR/Flk-1), and fins-like tyrosine kinase 1 (Flt-1 and Flt-4).
A further member of the tyrosine kinase growth factor receptor family is the fibroblast growth factor ("FGF") receptor subgroup. This group consists of four receptors, FGFR1-4, and many ligands. Although there is considerable alternative splicing, generally the receptors consist of a glycosylated extracellular domain containing 3 immunoglobin-like loops and an intracellular domain in which the tyrosine kinase sequence is interrupted by regions of a kinase insert domain.
Still another member of the tyrosine kinase growth factor receptor family is MET, often referred to as c-Met also known as human hepatocyte growth factor receptor tyrosine kinase (hHGFR). c-Met is thought to play a role in primary tumor growth and metastasis.
A more complete listing of the known RTK subfamilies is described in Plowman et al., DN&P, 7 (1994) 334-339, which is incorporated by reference, including any drawings, as if fully set forth herein.
In addition to the RTKs, there also exists a family of entirely intracellular PTKs called "non-receptor tyrosine kinases" or "cytoplasmic tyrosine kinases." This latter designation, abbreviated "CTK," will be used herein. CTKs do not contain extracellular and transmembrane domains. At present, over 24 CTKs in 11 subfamilies (Src, Frk, Btk, Csk, Abl, Zap70, Fes, Fak, Jak, LIMK and Ack) have been identified. The Src subfamily appear so far to be the largest group of CTKs and includes Src, Yes, Fyn, Lyn, Lck, Blk, Hck, Fgr, and Yrk. A further important group of CTKs is the Abl family including Abl and Arg. For a more detailed discussion of CTKs, see Bolen, J. B., Oncogene, 8 (1993) 2025-2031, which is incorporated by reference, including any drawings, as if fully set forth herein.
The serine/threonine kinases, STKs, like the CTKs, are predominantly intracellular although there are a few receptor kinases of the STK type. STKs are the most common of the cytosolic kinases; i.e. kinases that perform their function in that part of the cytoplasm other than the cytoplasmic organelles and cytoskelton. The cytosol is the region within the cell where much of the cell's intermediary metabolic and biosynthetic activity occurs; e.g., it is in the cytosol that proteins are synthesized on ribosomes. The STKs include CDk2, Raf, the ZC family of kinases, the NEK family of kinases, and BUB1.
RTKs, CTKs and STKs have all been implicated in a host of pathogenic conditions including, significantly, cancer. Other pathogenic conditions which have been associated with PTKs include, without limitation, psoriasis, hepatic cirrhosis, diabetes, angiogenesis, fibrosis, restenosis, ocular diseases, rheumatoid arthritis and other inflammatory disorders, immunological disorders such as autoimmune disease, cardiovascular disease such as atherosclerosis and a variety of renal disorders.
With regard to cancer, two of the major hypotheses advanced to explain the excessive cellular proliferation that drives tumor development relate to functions known to be PK regulated. That is, it has been suggested that malignant cell growth results from a breakdown in the mechanisms that control cell division and/or differentiation. It has been shown that the protein products of a number of proto-oncogenes are involved in the signal transduction pathways that regulate cell growth and differentiation. These protein products of proto-oncogenes include the extracellular growth factors, transmembrane growth factor PTK receptors (RTKs), cytoplasmic PTKs (CTKs) and cytosolic STKs, discussed above.
In view of the apparent link between PK-related cellular activities and wide variety of human disorders, it is no surprise that a great deal of effort is being expended in an attempt to identify ways to modulate PK activity. Some of these have been made to identify small molecules which act as PK inhibitors. WO 2006/066913 relates to imidazolopyridinyl benzamide derivatives and related compounds as src and lck kinase inhibitors.
WO 2004/024897 relate to imidazopyridines as modulators for the IgE immune response in the treatment of allergic and proliferative diseases.

Imidazo [4,5-B] pyridine and pyrrolo [2,3-B] pyridine protein kinase inhibitors

Abstract: their pharmaceutically acceptable salts, enantiomeric forms, diastereoisomers and racemates, the preparation of the above-mentioned compounds, medicaments containing them and their manufacture, as well as the use of the above-mentioned compounds in the control or prevention of illnesses such as cancer.


The present invention relates to insulin derivatives in which a lipophilic group having from 12 to 40 carbon atoms is attached to the α-amino group of the N-terminal amino acid in the B-chain or to the carboxy group of the C-terminal amino acid in the B-chain have a protracted profile of action.

Many diabetic patients are treated with multiple daily insulin injections in a regimen comprising one or two daily injections of a protracted insulin to cover the basal requirement supplemented by bolus injections of a rapid acting insulin to cover the meal-related requirements.
Protracted insulin compositions are well known in the art. Thus, one main type of protracted insulin compositions comprises injectable aqueous suspensions of insulin crystals or amorphous insulin. In these compositions, the insulin compounds utilized typically are protamine insulin, zinc insulin or protamine zinc insulin.
Certain drawbacks are associated with the use of insulin suspensions. Thus, in order to secure an accurate dosing, the insulin particles must be suspended homogeneously by gentle shaking before a defined volume of the suspension is withdrawn from a vial or expelled from a cartridge. Also, for the storage of insulin suspensions, the temperature must be kept within more narrow limits than for insulin solutions in order to avoid lump formation or coagulation.
While it was earlier believed that protamines were non-immunogenic, it has now turned out that protamines can be immunogenic in man and that their use for medical purposes may lead to formation of antibodies (Samuel et al., Studies on the immunogenicity of protamines in humans and experimental animals by means of a micro-complement fixation test, Clin. Exp. Immunol. 33, pp. 252–260 (1978)).
Also, evidence has been found that the protamine-insulin complex is itself immunogenic (Kurtz et al., Circulating IgG antibody to protamine in patients treated with protamine-insulins. Diabetologica 25, pp. 322–324 (1983)). Therefore, with some patients the use of protracted insulin compositions containing protamines must be avoided.
Another type of protracted insulin compositions are solutions having a pH value below physiological pH from which the insulin will precipitate because of the rise in the pH value when the solution is injected. A drawback is that the solid particles of the insulin act as a local irritant causing inflammation of the tissue at the site of injection.
WO 91/12817 (Novo Nordisk A/S) discloses protracted, soluble insulin compositions comprising insulin complexes of cobalt(III). The protraction of these complexes is only intermediate and the bioavailability is reduced.
Human insulin has three primary amino groups: the N-terminal group of the A-chain and of the B-chain and the ε-amino group of LysB29. Several insulin derivatives which are substituted in one or more of these groups are known in the prior art. Thus, U.S. Pat. No. 3,528,960 (Eli Lilly) relates to N-carboxyaroyl insulins in which one, two or three primary amino groups of the insulin molecule has a carboxyaroyl group. No specifically NεB29-substituted insulins are disclosed.
According to GB Patent No. 1.492.997 (Nat. Res. Dev. Corp.), it has been found that insulin with a carbamyl substitution at NεB29 has an improved profile of hypoglycaemic effect.
P laid-open patent application No. 1-254699 (Kodama Co., Ltd.) discloses insulin wherein a fatty acid is bound to the amino group of PheB1 or to the ε-amino group of LysB29 or to both of these. The stated purpose of the derivatisation is to obtain a pharmacologically acceptable, stable insulin preparation.
Insulins, which in the B30 position has an amino acid having at least five carbon atoms which cannot necessarily be coded for by a triplet of nucleotides, are described in JP laid-open patent application No. 57-067548 (Shionogi). The insulin analogues are claimed to be useful in the treatment of diabetes mellitus, particularly in patients who are insulin resistant due to generation of bovine or swine insulin antibodies.
U.S. Pat. No. 5,359,030 (Ekwuribe, Protein Delivery, Inc.) describes conjugation-stabilized polypeptide compositions for oral or parenteral administration comprising a polypeptide covalently coupled with a polymer including a linear polyalkylene moiety and a lipophilic moiety, said moieties being arranged so relative to each other that the polypeptide has an enhanced in vivo resistance to enzymatic degradation.
EP 511600 A2 relates i.a. to protein derivatives of the formula [protein][Z]n wherein [protein] represents a protein having n amino residues each derivable from an amino group by removal of one of its hydrogen atoms, in stead of amino groups, [Z] is a residue represented by the formula —CO—W—COOH wherein W is a divalent long chain hydrocarbon group which may also contain certain hetero atoms and n represents an average of the number of amide bonds between [Z] and [protein]. It is mentioned that the protein derivatives of the invention have an extremely prolonged serum half-life as compared with the proteins from which they are derived and that they exhibit no antigenicity. It is also mentioned, that insulin is one of the proteins from which derivatives according to the invention can be made, but no specific insulin derivatives are disclosed in EP 511600 nor is there any indication of a preferred [Z] or (a) preferred position(s) in which [Z] should be introduced in order to obtain useful insulin derivatives.
In the present specification, whenever the term insulin is used in a plural or a generic sense it is intended to encompass both naturally occurring insulins and insulin analogues and derivatives thereof. By "insulin derivative" as used herein is meant a polypeptide having a molecular structure similar to that of human insulin including the disulphide bridges between CysA7 and CysB7 and between CysA20 and CysB19 and an internal disulphide bridge between CySA6 and CysA11, and which have insulin activity.
However, there still is a need for protracted injectable insulin compositions which are solutions and contain insulins which stay in solution after injection and possess minimal inflammatory and immunogenic properties.
One object of the present invention is to provide human insulin derivatives, with a protracted profile of action, which are soluble at physiological pH values.
Another object of the present invention is to provide a pharmaceutical composition comprising the human insulin derivatives according to the invention.
It is a further object of the invention to provide a method of making the human insulin derivatives of the invention.

This patent is subject to a terminal disclaimer.


The invention relates to a process for producing improved water absorbing resin comprising the steps of treating water absorbing resin particles (A) with an aqueous solution of a water-soluble compound (B) and a crosslinking agent (C), reacting, and obtaining resin particles crosslinked in the surface vicinity; and a water absorbing resin obtained by this process possessing the absorption characteristics of an absorbency under a pressure-free state of 50 times or more to physiological saline solution, and an absorbency under the pressurized state of 30 times or more to physiological saline solution. The water-soluble compound (B) is at least one water-soluble compound selected from the group consisting of alkylene-oxide adducts of monofunctional alcohols (1), a monofunctional salts of organic acids (2), and lactams (3), and inert to (A) and (C); and the crosslinking agent (C) has two or more functional groups capable of reacting with (A). The obtained improved water absorbing resin possesses an excellent absorbing capacity whether under no pressure or under pressure, and does not form lumps when brought into contact with water. The initial absorption rate is superior, and the dry feeling of the gel after absorbing water is excellent. Therefore, it is used beneficially as a sanitary material, cold insulating material, water sealing materials, and many others.

1. Field of the Invention
The present invention relates to a process for producing an improved water absorbing resin, and a water absorbing resin obtained by the process. More specifically, it relates to a process for producing an improved water absorbing resin by treating and crosslinking the vicinity of the surface of water absorbing resin particles with an aqueous solution of a specific water-soluble compound and a crosslinking agent, and a water absorbing resin obtained by the same process having a large absorbing ability in all circumstances, whether in a pressure-free state or in a pressurized state.
2. Description of the Prior Art
Hitherto, water absorbing resins have been widely used in hygienic materials such as sanitary materials and paper diapers, water retainers for soil, and others. Examples of such water absorbing resins are known to include crosslinked polyacrylic acid salts, self-crosslinking type polyacrylic acid salts, crosslinked copolymers of starch-grafted acrylic acid salts, copolymers of vinyl alcohol-acrylic acid salt, hydrolyzates of crosslinked copolymer of acrylamide, neutralized copolymers of crosslinked isobutylene-maleic anhydride, and crosslinked carboxy methyl cellulose salts.
The method for obtaining a water absorbing resin is mainly intended to make a water-soluble resin insoluble in water by slightly crosslinking. The crosslinking methods thereof include a method of adding a crosslinking agent when polymerizing a hydrophilic monomer and crosslinking simultaneously with polymerization, or a method of uniform crosslinking between molecules of water soluble polymers by reacting crosslinking agent to the water-soluble polymers.
The water absorbing resins obtained by these crosslinking methods have a minimized content of the crosslinking agent in order to enhance the absorbency. Accordingly, the water absorbing resin is weak in the gel strength and low in the absorbency under pressure. Moreover, inside the water absorbing resin, water-soluble components coexist, which are responsible for lowering the absorption rate, lowering the stability of the water absorbing gel by elution of water-soluble components after absorption, and deterioration of the dry feeling of water absorbing gel. On the other hand, the method of enhancing the crosslinking density by increasing the use of crosslinking agent is also known, but when uniformly crosslinked at high density, the absorption capacity, which is the basic feature of the water absorbing resin, is lowered, which is not preferable.
To solve these problems, as shown in items 1 to 4 below, methods for reforming the water absorbing resin particles have been proposed.
1 Method of dispersing a water absorbing resin in a large quantity of organic solvent such as alcohol, ketone and ether containing water, and crosslinking by adding a crosslinking agent (Japanese Patent Application Laid Open No. 44627/1982).
2 Method of crosslinking a water absorbing resin in water containing state with the water content adjusted to 10 to 40 wt. % (Japanese Patent Application Laid Open No. 62665/1984).
3 Method of absorbing crosslinking agent and water into water absorbing resin in the presence of inorganic powder to avoid the coagulation, and heating while stirring so as to crosslink and remove water simultaneously (Japanese Patent Application Laid Open No. 163956/1985).
4 Method of crosslinking by dispersing in a large quantity of hydrophilic inert solvent with boiling point of 100.degree. C. or higher, in the presence of 1.5 to 5.0 parts by weight of water and inert inorganic powder, to 1 part by weight of water absorbing resin (Japanese Patent Application Laid Open No. 147475/1985).
Of these reforming methods, however, in the method of 1, although a water absorbing resin with an improved absorption rate is obtained, a step for removing a large amount of the organic solvent having low boiling point is required, and it is hardly suited to industrial application. Furthermore, in this step of removing the organic solvent, the crosslinking agent permeates into the central part of the water absorbing resin particles together with the concentrated moisture so as to crosslink up to the inside of the resin particles, thereby lowering the absorption performance or mutually coagulating the water absorbing resin particles by means of the concentrated moisture to form lumps, and the working efficiency is poor.
In the method of 2, the crosslinking agent permeates into the central part of the water absorbing resin particles containing large amount of water to crosslink up to the inside of the resin particles, and the absorption performance is lowered, and the water absorbing resin particles containing water are mutually coagulated to form lumps.
In the methods of 3 and 4, the mutual coagulation of water absorbing resin particles may be somewhat prevented by the presence of the inorganic powder, but since the crosslinking agent is adsorbed not only by the water absorbing resin but also by the inorganic powder, crosslinking tends to become nonuniform, and sufficient performance may not be always exhibited. Furthermore, in the method of 4, since a large amount of water of 1.5 to 5.0 times of the water absorbing resin is used, the crosslinking agent may permeate into the central part of the water absorbing resin containing water, and the absorption performance is lowered.

Process for producing improved water absorbing resin and resin made by the same


A remote control device for a vessel is installed in a vessel and remotely controls a vessel propulsion device of the vessel. The remote control device includes an operation member, an operation load applying mechanism, a control section, and an actuator. The operation member is supported rotatably around a rotation axis, and is operated by an operator to switch the shift position of a forward-reverse switching mechanism in the vessel propulsion device according to the operation angle of the operation member. The operation load applying mechanism applies an operation load to the operation member. The control section controls the operation load. The operation load applying mechanism includes an actuator that adjusts the operation load. The control section is arranged to control the actuator based on a vessel speed of the vessel.

1. Field of the Invention
The present invention relates to a remote control device for a vessel that is installed in a vessel and remotely controls a vessel propulsion device, and a remote control method for a vessel propulsion device.
2. Description of the Related Art
A vessel propulsion device such as an outboard motor is attached to a hull of a vessel so as to apply thrust to the hull. For example, an outboard motor includes an engine and propeller blades. The outboard motor rotates the propeller blades in response to a torque from the engine to generate thrust. The outboard motor further includes a forward-reverse switching mechanism that changes the rotating direction of the propeller blades. By switching the shift position in the forward-reverse switching mechanism between a forward shift position and a reverse shift position, the rotating direction of the propeller blades is switched.
An electronic control type remote control device that remotely controls such a vessel propulsion device is known. In this electronic control type remote control device, an operation angle of an operation lever is detected, and according to the detected operation angle, the vessel propulsion device is controlled. Therefore, the operation lever itself is operable with a small operation load.
However, for example, in a case where a hull rocks during high-speed traveling, etc., there is a need to hold the position of the operation lever. Therefore, for example, in Japanese Unexamined Patent Application Publication No. 2006-62481, a device arranged to increase a frictional force to be applied to the support shaft of the operation lever as the operation angle of the operation lever increases is disclosed. In detail, in this device, the support shaft of the operation lever has an oval shape (cam shape) in section, and the device is arranged to apply a frictional force to the support shaft by a pressing mechanism.

Remote control device for vessel and remote control method for vessel propulsion device


A connector for use with a ribbon cable grounds alternate conductors of a fine pitch ribbon cable, and allows selected conductors associated with the connector signal contacts to be grounded. The connector is readily adaptable to differing grounding configurations. The connector includes a plurality of signal contacts housed within an insulative body. The signal contacts electrically connect to alternate individual conductors (the "signal conductors") of the ribbon cable. A first ground bus is electrically connected to the conductors of the ribbon cable which are not connected to a signal contact (the "ground conductors"). A second ground bus electrically connects selected conductors of the signal conductors with the ground conductors. By altering the second ground bus, the grounding scheme of the connector can easily and quickly be altered. A latching cover is provided for securing the ribbon cable to the connector body and against the signal contacts, the first ground bus and the second ground bus.

The present invention relates to electrical connectors for use with flat multi-conductor ribbon cables, and particularly to connectors compatible with high-speed data transmission.
In modern electronic systems, such as computer systems, flat multi-wire cables (ribbon cables) are commonly used to carry signals to and from printed circuit boards, disk drives, and the like. As the speed of data transmission in electronic systems increases, the problem of crosstalk between adjacent signal wires of the ribbon cable increases dramatically. Crosstalk results from electromagnetic interference and can cause reduced signal clarity, including damage to the integrity of the data being transmitted.
To combat the problem of crosstalk, the preferred connector and ribbon cable assembly for high-speed signal transmission is a configuration that provides a ground-signal-ground (G-S-G) wire configuration. In this manner, signal wires are separated by at least one ground wire, which thereby reduces or eliminates crosstalk and enables higher speed signal transmission without significant signal degradation.
In a conventional connector, each wire of the ribbon cable is connected to a signal contact in the connector, and desired signal contacts (and associated wires) are grounded. Thus, in a conventional connector each ground wire requires a corresponding grounded signal contact within the connector body. This arrangement reduces the number of contacts in the connector available for signal transmission. In other words, to provide the preferred ground-signal-ground wire configuration, about one-half of the contacts in the connector are dedicated for grounding, thus leaving only the remaining one-half of the contacts in the connector for signal transmission. This means that for a required number of signal lines, the number of contacts in a connector (and thus the size of the connector) must be increased to accommodate the additional ground lines, unless a novel connector design is developed.
The art is replete with connectors for terminating ribbon cables. As is common in the electronics industry, standardized connector specifications (often referred to as form factors) have evolved for specific applications to ensure the compatibility of components which originate from different manufacturers. A well known standardized connector used with ribbon cables is the AT attachment (ATA) interface. The ATA interface, as originally designed, utilizes a 40 pin connector and is used to terminate a 40 conductor ribbon cable. The wire configuration of the original ATA interface is not ground-signal-ground, meaning that the signal wires are not separated by ground wires. Thus, the original ATA design is susceptible to crosstalk as data transmission speeds increase.
As the electronics industry has continued to develop systems that operate at higher and higher speeds, the ATA interface has been pushing the limits of reliable performance at transmission speeds of 33 Mbytes/s. Because the introduction of devices with transmission speeds of 66 Mbytes/s and higher is imminent, changes to the ATA interface standard have been made by the Small Form Factor (SFF) Committee. The new SFF standard, SFF-8049, retains the existing 40 pin connector interface, but replaces the original 40 conductor ribbon cable with an 80 conductor ribbon cable. The new SFF standard requires that the ground connections all occur within the same 40 pin form factor of existing ATA connectors. To retain the existing size and grounding configuration of the 40 pin connector, the 80 conductor ribbon cable has a pitch of 0.025 inch, which is one half of the 0.050 inch pitch of the earlier 40 conductor cable. This means that the distance between the wires of the 80 conductor cable is only one half of the distance between the wires of the 40 conductor cable. Alternating wires of the 80 conductor ribbon cable are connected to the grounded signal contacts of the ATA interface such that ground wires are interposed between each signal wire to minimize crosstalk and the associated signal degradation. Obviously, because only 40 signal contacts are present in the connector, each grounded conductor cannot have its own grounded signal contact. Therefor, new and unique connector designs are required to ground the additional wires of the 80 conductor ribbon cable within the 40 pin connector form factor.
Others have developed connectors for this purpose. For example, Circuit Assembly Corporation of Irvine, Calif., USA, manufactures a connector (available under the part number CA-40ATAS-C-X01) which utilizes a ground bus located inside the connector between the two rows of traditional insulation displacement contacts (IDC). A schematic representation of a portion of the Circuit Assembly connector is shown in FIG. 1. The ground bus utilizes insulation displacement contacts 10 placed on a 0.050 inch pitch to mass-terminates every other conductor of the 80 conductor ribbon cable. The grounded signal contacts 12 of the 40 pin ATA interface are electrically connected to the ground bus by conductive wipers 14 which extend between the ground bus and the grounded signal contacts 12. While the Circuit Assembly connector performs adequately, it has several disadvantages. The primary disadvantage is that the wiper contact between the ground bus and the selected grounded signal contacts is susceptible to damage during the assembly process and performance degradation over time due to surface corrosion which develops at the wiper-contact junction. Further, because the ground bus is inserted into connector housing between the signal contacts, molding the housing and assembling the components is difficult, due to the close proximity of the housing cavities which receive the signal contacts and the ground bus. The Circuit Assembly connector also has the disadvantage of being dedicated to a specific wire configuration. That is, if it is necessary to change the signal/ground wire configuration (for example, due to a form factor alteration or for a different connector application), an entirely new housing must be molded and a new ground bus designed with relocated wipers for making electrical connection to the connector contacts.
AMP Incorporated of Harrisburg, Pa., USA, manufactures a connector similar to the above described Circuit Assembly connector. Like the Circuit Assembly connector, the AMP connector (available under the part number 120605-X) utilizes a ground bus located inside the connector between the two rows of traditional insulation displacement contacts (IDC). A schematic representation of a portion of the AMP connector is shown in FIG. 2. The ground bus uses insulation displacement contacts 20 to mass-terminates every other conductor of the 80 conductor ribbon cable. In addition, the ground bus also terminates the wires associated with the grounded signal contacts 22. This means that at certain locations the AMP ground bus must terminate adjacent wires of the 80 conductor cable, which are spaced only 0.025 inch apart. This presents a disadvantage for the AMP ground bus, because it is very difficult to manufacture insulation displacement contacts at such a small pitch. As a result, certain design compromises must be made which decrease the reliability of the connections made by the ground bus. For example, as the pitch of the IDC features decreases, the amount of material available to form the IDC decreases, which in turn can affect the compliance of the IDC. If the compliance of the IDC is inadequate, the connection may fail over time as thermal cycling of the connector occurs. An illustration of an insulation displacement contact 30 for use with conductors 32 having a 0.050 inch pitch is shown in FIG. 3A, while an illustration of an insulation displacement connector 34 for use with conductors 36 having a 0.025 inch pitch is shown in FIG. 3B. The IDC 34 of FIG. 3B is less compliant than the IDC 30 of FIG. 3A, due to the presence of conductor 36', which reduces the ability of IDC arms 37 to flex. The IDC 34 of FIG. 3B is thus not as reliable and more susceptible to damage than the IDC 30 of FIG. 3A. It is therefor preferred to avoid the use of insulation displacement connectors like that shown in FIG. 3B.
Adaptability of the connector design is especially important in light of the new ATA interface standard. The ATA interface and cable assembly connects the motherboard to two devices, which could, for example be a disk drive or a CD-ROM drive. The original standard allowed any connector to be connected to either device or to the motherboard. This is not true with the revised standard, which requires that the grounding scheme of each connector be individualized to a specific location, such that the connectors for the motherboard, the first device, and the second device cannot be substituted for each other.
Therefore, it would be very beneficial to provide a connector which reliably grounds alternate wires of a fine pitch ribbon cable, which also allows selected wires associated with the connector signal contacts to be grounded, which is easily manufactured and assembled, and which is readily adaptable to differing wire configurations at minimal cost.


A sports goal is provided having a pair of vertically extending posts and an interconnecting cross bar, wherein at least one of the posts and the cross bar include a curvilinear section. The posts extend from bottom ends adjacent a playing surface to upper ends interconnected with the cross bar, wherein the bottom ends of the posts and the junctions with the cross bar are located at the vertices of a rectangle.

1. Field of the Invention
The present invention relates to sports goals, and more particularly, to a sports goal for cooperating with a playing surface, wherein the sports goal has a curvilinear portion for enhancing scoring opportunities.
2. Description of Related Art
Sports goals have traditionally been formed of a rectangular frame with a net connected to the frame to capture an object passing through the frame. Such representative goals include soccer, hockey, water polo, lacrosse as well as handball.
Many sports have found increased fan appreciation, when scoring increases. However, changes to rules regulating play are typically required to provide for such increases in scoring, and rule changes are often met with fan and participant resistance. Further, new rules often leads to inconsistent interpretation and application which can lead to fan dissatisfaction and participant frustration.
In hockey, the scoring average has actually decreased over the past years, as goalies are now physically larger than their earlier counterparts and equipment, such as pads, has become lighter and larger. The decreased scoring has been attributed as a source of some fan dissatisfaction.
Therefore, the need exists for allowing increased scoring opportunities, without changing fundamental aspects of a given sport. The need also exists for a sports goal that will not significantly disadvantage either the offense or defense, and particularly a goalie.

Sports goal having curvilinear frame section


An economical system and method for eliminating manual operations in smaller scale animal feeding water bottle management is provided. A hand held cap removal tool captures the perimeter of the water bottle cap for automatic capping or decapping. Provisions for suspending the tool for convenient universal motion over a work area are described. The cap removal tool accommodates straight and angled water delivery tubes and most popular water bottle cap sizes.

Medical research depends on animal experimentation which demands large numbers of animals, such as mice, rats, guinea pigs, and so on. Depending on the nature of the project animals may be housed singly or in multiples in each cage. In either case, a container for water is usually essential for each cage. In the past and to some extent even today this problem was addressed by providing a rubber stopper with a through hole, inserting a specially designed stainless steel tube in the hole, and inserting the rubber stopper into a suitable glass or plastic water bottle. Obvious problems with reliability and labor considerations led to the growing use of metal or plastic screw caps to replace the rubber stoppers, and matching threaded neck water bottles. While this provided reliable animal watering devices the lab technician was still faced with dealing with perhaps thousands of bottles each day. Each bottle cap has to be unscrewed to remove the cap, the bottle emptied of remaining water, filled with fresh water, and finally the cap resecured. This tedious work is not only boring and costly, but can lead to physical injury such as carpal tunnel syndrome. It has been estimated that repetitive motion of this kind can lead to worker complaints costing up to $15,000 per complaint in terms of lost productivity, disability, and medical costs.
To address this tedious problem of uncapping, dumping, and recapping bottles a variety of automated animal water bottle handling systems have been devised, including mechanical and computer programmed. These systems are currently commercially available for large scale animal requirements. However, for smaller research requirements the problem persists. The present invention provides a solution by providing a simple, economical hand held water bottle decapping and recapping system specifically for those applications still depending on objectionable manual operations.
It is therefore a primary object of the present invention to provide a system for capping and decapping bottles with a hand held mechanism.
An additional object of the present invention is to fill the gap between automatic and manual bottle capping and decapping procedures.
A further object of the invention is to speed up the installation and removal of caps on water bottles.
Still another object of the invention is to minimize or eliminate physical injury to workers, such as carpal tunnel syndrome.
Yet another object of the invention is to provide a consistent and predetermined torque of each cap so as to minimize leakage.

Animal water feeding bottle cap handling system


A pressure measuring system for a refrigeration system, such as a refrigeration system used in a commercial air conditioning system, comprises a converter (42) for converting a pressure being measured into a digital signal representing the measured pressure and a processor (54) for calculating a corresponding boiling point temperature for a selected refrigerant at the measured temperature. The system also includes a selector for selectively inputting the boiling point temperature-pressure relationship or coefficient of a selected refrigerant into the processor, as well as a display (60) for displaying the measured pressure and the calculated boiling point temperature.

In order to measure or monitor whether a refrigeration system is operating correctly or to diagnose a problem, it is necessary to measure the pressure of the refrigerant in either of the high and low pressure sides of the system or both. Basically, the conventional units which are used for this purpose are manifolds with flexible tubes which are connected to pressure nipples provided on the refrigeration system. The manifolds are provided with analog gauges. One gauge is connected to the high pressure side and one gauge is connected to the low pressure side of the refrigeration system. The gauges measure pressure but corresponding boiling point or saturation temperature values are given for the refrigerant at the different pressure values. The boiling point or saturation temperature is the temperature at which a phase change between the vapour and liquid phases occurs for the refrigerant at a particular pressure.
It is an object of the present invention to provide a pressure measuring system which will facilitate the operations of carrying out pressure measurements and obtaining corresponding boiling point temperature values for different refrigerants.

Pressure measurement system for refrigeration system


A lubricating structure of an automatic transmission is provided which is capable of realizing sufficient cooling lubrication with lubricating oil, utilizing a given space efficiently, and avoiding the possibility of an increase in the weight of assembly parts by checking an increase in the number of the assembly parts. The rotational direction of a front planetary gear device (46) and the like is changed by engagement or disengagement of each of multiplate clutch plates (35, 43) of a plurality of multiplate clutch devices (33, 40), and thereby the transmission state of driving force is shifted. A 2-4 brake clutch (33) of the multiplate clutch devices (33, 40) is engaged in two forward gears and is disengaged in a forward gear between the two forward gears. A reverse clutch (40) of the multiplate clutch devices (33, 40) is disposed substantially in the same position as that of the 2-4 brake clutch (33) in the axial direction and outside of the 2-4 brake clutch (33) in the radius direction. The reverse clutch (40) uses a clutch drum (36) of the 2-4 brake clutch (33) as a clutch hub.

1. Field of the Invention
This invention relates to a lubricating structure of an automatic transmission principally used for controlling the transmission of driving force in a vehicle.
2. Description of the Prior Art
As shown in FIGS. 4 to 6, there has been known a conventional lubricating structure of an automatic transmission as disclosed in, for example, Japanese Patent Application Early Laid-Open Publication No. Sho 62-288753. This type of conventional automatic transmission has a transmission gear device which consists of four forward gears and one reverse gear by which gear shifting is performed.
Referring to FIGS. 4 to 6, a cylindrical drum 5 is rotatably connected to a front sun gear 4 by the medium of a connecting shell 3 around an input shaft 1b in a case 2 of an automatic transmission 1.
In the drum 5, a reverse clutch device 6 and a high clutch device 7 are disposed parallel to the input shaft 1b. The reverse clutch device 6 and the high clutch device 7 are multiplate clutch devices and have a function of engaging or disengaging a multiplate clutch plate by the shoving pressure of a clutch piston so as to shift a transmission state of driving force. A clutch drum 6a of the reverse clutch device 6 is connected to the drum 5 and is rotated by the rotation of the drum 5.
A brake band 9 of a band brake device 8 is attached to the circumferential surface of the drum 5. The rotation of the drum 5 is controlled by a piston 11 of a band servo device 10 shown in FIG. 6.
In the circumferential surface of the drum 5, there is formed an oil hole 15 through which lubricating oil is supplied to a space defined between sliding surfaces of the brake band 9 and the drum 5.
In the rear of the connecting shell 3, a front planetary gear device 12 and a rear planetary gear device 13 are disposed parallel to the input shaft 1b.
A front planet carrier 14 in the front planetary gear device 12 is linked to a high clutch hub 16 in the high clutch device 7 through a cylindrical sleeve portion 17.
A rear planet carrier 18 in the rear planetary gear device 13 is linked to a front internal gear 19 in the front planetary gear device 12 and is also linked to an output shaft 20 disposed coaxially with the input shaft 1b.
For example, in the third forward gear, the high clutch device 7 is engaged whereas the band brake device 8 is disengaged. On the other hand, in the fourth forward gear, the band brake device 8 as well as the high clutch device 7 is engaged, and the drum 5 is then fixed to the transmission case 2 and thereby the front sun gear 4 is also fixed thereto.
The rotational driving force inputted by the input shaft 1b is transmitted from the high clutch device 7 to the front planet carrier 14 via the high clutch hub 16, and thereby a front planetary gear 21 is rotated around the front sun gear 4.
Accordingly, the rotation of the front internal gear 19 is accelerated, and thereby the output shaft 20 connected to the rear planet carrier 18 is rotated at a speed equal to or higher than the input shaft 1b.
Oil paths 22 and 23 are formed in the input shaft 1b and the high clutch hub 16, respectively. When the drum 5 is rotated, lubricating oil is supplied to the front planetary gear device 12 and the rear planetary gear device 13 via the oil paths 22 and 23, and is also supplied to the space defined between the sliding surfaces of the brake band 9 and the drum 5 through the oil hole 15 formed in a circumferential part of the drum 5 via the oil paths 22 and 23, the high clutch device 7, and the reverse clutch device 6.
However, in a lubricating structure of this type of automatic transmission, in the fourth forward gear, the band brake device 8, which is disposed outside of the high clutch device 7 and fixes the drum 5, is supplied with operating oil and is engaged at the same time that the high clutch device 7 is engaged.
Accordingly, the lubricating oil which has lubricated and cooled the high clutch device 7 via the oil paths 22 and 23 is discharged from the oil hole 15 and is supplied to the space between the sliding surfaces of the brake band 9 and the drum 5 without lowering its high temperature. Therefore, high cooling efficiency has not been obtained.
Besides, as mentioned above, the band brake device 8, which is disposed outside of the high clutch device 7 and fixes the drum 5, is supplied with operating oil and is engaged simultaneously with the engagement of the high clutch device 7. This has caused an increase in the quantity of operating oil. Moreover, since the band brake device 8 is disposed outside of the high clutch device 7, lubricating oil is dispersed when the drum 5 is rotated. This has made it difficult to supply a predetermined quantity of oil to the band brake device 8.
The band brake device 8 is engaged in the second forward gear and the fourth forward gear and is disengaged in the third forward gear. Thus, the engagement and disengagement for the gearshifting of the band brake device 8 are repeatedly carried out with high frequency of use even when ordinary acceleration is carried out (for example, when the gear is shifted in sequence of the first gear, the second gear, the third gear, and the fourth gear). Accordingly, there has been a fear that production costs may be raised because friction materials superior in heat-resisting property must be used for the sliding surfaces of the brake band 9 and the drum 5 if sufficient cooling cannot be expected.
As a result of disposing the band brake device 8 outside of the drum 5 as shown in FIG. 6, a given space cannot be utilized efficiently. Furthermore, the band brake device 8 is constructed of relatively large parts, such as the brake band 9, the band servo device 10, and the like. For this reason, an increase in the number of the assembly parts leads to a raise in production costs and to an increase in the weight of the assembly parts.

Lubricating structure of automatic transmission


A resin-sealed module is provided which reduces the warpage of a substrate and the detachment between a sealing resin and the substrate which occur during re-reflow, has the excellent flatness of the top and bottom surfaces, and reduces the occurrence of the short failures. A resin layer made of a thermoplastic resin is arranged on top of a substrate, and a resin layer made of a thermosetting resin is arranged on top of this resin layer, thereby reducing the warpage of the substrate and the detachment between the sealing resin and the substrate which occur during re-reflow.

Field of the Invention
The present invention relates to a resin-sealed module in which electronic components are sealed with the resin.
Description of the Related Art
As a resin-sealed module according to the related art, for example, a module described in Patent Document 1 is known. Hereinafter, the resin-sealed module described in Patent Document 1 will be illustrated with reference to FIG. 3. FIG. 3 is a cross-sectional view of the resin-sealed module.
A resin-sealed module 100 includes an insulating substrate 101, and a sealing resin layer 103 made of a thermosetting resin. An IC chip 104 and an electronic component 105 mounted onto the insulating substrate 101 as described below are embedded in the sealing resin layer 103. A wiring conductor 102 is formed on the insulating substrate 101. The IC chip 104 is electrically connected to the wiring conductor 102 by a solder bump 106. An electrode terminal 107 of the electronic component 105 is electrically connected to the wiring conductor 102.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2007-042829


The invention comprises improvements to sewing machines for increasing the throat clearance of the machine. The improvements relate to 1) modifications to mechanical components of the machine to increase the throw and upper travel limits of the presser foot, upper feeding foot, needle and spreader, 2) an adjustment for allowing the speed of the upper walking foot to be variable relative to the speed of the lower walking foot, and 3) an improved biasing spring for biasing the presser foot downward.

Industrial sewing machines have long been used for sewing together relatively thick materials such as mattress cover$ and upholstery. Sewing machines used for sewing such thick materials must be adapted to provide adequate vertical clearance for the material to fit through the throat of the machine. The throat plate, the plate upon which the material rests as it is sewed, defines the bottom plane of the space in which the material must fit in the throat of the machine. Accordingly, the thickness of the material which can be sewn by the machine is dictated by the clearance between the throat plate and the lowest of the upper travel limit of the 1) needle, 2) presser foot and 3) upper walking foot. Although the needle, presser foot and upper walking foot must provide an unusually large clearance when at their upper travel limit, the needle must still be able to plunge below the throat plate to place a stitch in the material. Accordingly, the needle's throw (i.e., the distance traveled by the needle from the top of its motion to the bottom) on such a machine must also be unusually long. If the machine is to be able to be used with thin as well as thick materials, the same is true of the throw of the presser foot and the upper walking foot. The presser foot and upper walking foot must be able to get very close to the throat plate in order to contact very thin materials but also must be able to provide larger clearance for very thick materials.
Typically, the lower travel limit of the presser foot in a sewing machine is limited by contact of the presser foot with the throat plate. However, this manner of limiting motion is undesirable because the impact of the presser foot with the throat plate causes unnecessary wear and tear on the components of the device. It is also desirable to be able to adjust the downward force of the presser foot on the material in order to accommodate for materials of different thickness.
In sewing machines which comprise upper walking feet, the upper walking foot is typically positioned directly over the lower walking foot so that the material is "clamped" between the upper and lower walking feet. U.S. Pat. No. 4,449,464 discloses a sewing machine including upper and lower walking feet. Some sewing machines also include a secondary (or rear) lower walking foot spaced rearwardly of the upper walking foot and primary lower walking foot. Reference is made to U.S. Pat. Nos. 4,166,422, 3,995,571 and 3,530,809 as examples of sewing machines comprising mating upper and lower walking feet and an additional secondary lower walking foot spaced rearwardly away from the other walking feet. In certain sewing situations, it is desirable for the various walking feet to move at different speeds relative to one another. This is typically useful where one wishes for the material to bunch as it is sewed. For instance, when bunching of the material is desired, the forward lower walking foot should move at a speed slower than the rearward lower walking foot. Forward is defined herein as the direction in which the material is advanced as it is sewn. In fact, in certain applications, it is desirable for the upper walking foot to travel at a different speed than the primary lower walking foot (which it is directly above), thus causing the upper layer of material to travel at a different speed than the lower, causing only one of the layers to bunch as it is sewed.
In overcast stitching, thread is wrapped once around the edge of the material for each stitch. In machines adapted for performing overcast stitching, two strands of thread, an upper strand which is looped through an eye in the tip of the needle and a lower strand which is looped through a looper below the throat plate, are intertwined to form the overcast stitches. The stitch will not be described herein as it is conventional in the art and not material to the present invention except insofar as improvements have been made to certain mechanical components of an overcast stitching sewing machine. Accordingly, the following discussion of overcast stitching is not intended to be complete but simply describes the necessary machine components for accomplishing overcast stitching.
FIGS. 1A 1B and 1C illustrate the movement of the needle, looper and spreader of an overcast stitching sewing machine through one stitch cycle. The strands of thread are not shown for ease of illustration. When the tip of the needle 70 is plunged below the throat plate 11, as shown in FIG. 1A, a looper 183, rotating about axis 187 in the direction of arrow 65, passes close by the needle tip and traps the upper thread from needle 70 underneath arm 183a. Looper 183 transports the trapped thread horizontally beyond the edge of the material 77 as the needle continues its stroke and begins moving upwardly, as illustrated in FIG. IB. When the looper reaches beyond the edge of the material (FIG. 1B), spreader 180, moving upwardly, grabs the lower thread from looper 183 by trapping it in fork 182 and transports it around the edge of the material bringing it up and over the material and positioning it adjacent the tip of needle 70 as the needle reaches the top of its throw and begins its downward stroke again (FIG. 1C). The needle removes the thread from the spreader by trapping it between the needle tip and the upper thread strand which passes through the eye 67 in the needle tip. At the moment when the thread is trapped by needle 70, spreader 180 reaches the top of its stroke and reverses direction, moving downwardly and to the right, releasing the thread from fork 182. The needle then plunges through the material transporting the thread grabbed from the spreader through the material causing a stitch to be formed over the edge of the material returning to the position shown in FIG. 1A. The apparatus then repeats the cycle to make the next stitch.
Commonly, an overcast stitching machine is also provided with a knife system comprising upper and lower knives which cut the material just before it is advanced through the sewing area so as to form the edge close to the needle and parallel to the stitching. The knife assembly is rearwardly of the sewing area and typically comprises a stationary lower knife and a reciprocating upper knife which moves up and down to meet with the lower knife during the lower portion of its travel to act as a scissor to cut the material before it is advanced into the sewing area.
Accordingly, it is an object of the present invention to provide an improved sewing machine.
It is a further object of the present invention to provide a sewing machine with a very large vertical clearance between the throat plate and the upper travel limits of the needle, presser foot and upper walking foot.
It is yet another object of the present invention to provide a sewing machine with variable speed walking feet.
It is yet another object of the present invention to provide a sewing machine in which the lower travel limit of the presser foot is adjustable relative to the throat plate.
It is a further object of the present invention to provide a sewing machine in which the downward force of the presser foot can be set to any desired force.
It is another object of the present invention to modify existing sewing machines to improve their utility.
It is yet one more object of the present invention to provide an overcast stitch sewing machine having high clearance for accepting thick materials and having an increased throw and upper travel limit of the spreader.