Method and apparatus for distributing brake torque between at least one first and one second brake device on a motor vehicle including at least two wheel pairs. The first brake device is a friction brake which acts on at least one wheel pair and the second brake device acts on at least the driven wheel pair via the transmission and is disposed before the clutch device of the transmission. Brake torque is distributed between the first and the second brake device in a manner that compensates for the loss of brake torque which occurs when the second brake device is disengaged by the clutch device of the transmission.

It is known to arrange auxiliary brakes in a vehicle as a complement to the service brakes of the vehicle. Auxiliary brakes are primarily used in heavy-duty vehicles with the principal aim of saving the service brakes of the vehicle, especially when driving on long downhill slopes where there is a desire to brake to maintain fairly constant speed. The use of the auxiliary brakes allows the service brakes to be kept fresh, so that they can provide maximum braking force when the vehicle really does need to slow down quickly. The service brakes have a much more powerful braking action than the auxiliary brakes, partially owing to the fact that the service brakes are normally arranged on all the wheels of the vehicle. The auxiliary brakes normally act only on the driving wheels.
It is further known to differentiate between so-called primary and secondary auxiliary brakes in a vehicle. Primary and secondary alludes to the positioning of the auxiliary brake before or after the main gearbox of the vehicle. Examples of primary auxiliary brakes are ISG (Integrated Starter & Generator) and retarders. A retarder is usually of the hydrodynamic retarder or the electromagnetic retarder type. These are disposed between the engine and the main gearbox. A primary auxiliary brake can also be constituted by various types of engine brakes, for example compression brake, exhaust brake or the internal friction of the engine. The braking energy in a compression brake and exhaust brake is converted mainly into heat, which, in large part, is dissipated via the engine cooling system, though it should be noted that a substantial part (about 40% of the braking energy) accompanies the vehicle exhaust gases out through the exhaust system. The brake power which can be delivered by a primary auxiliary brake is dependent on the engine speed, and for this reason it is advantageous to maintain a relatively high engine speed whenever a primary auxiliary brake is used.
The internal friction of the engine can be adjusted by injecting a certain quantity of fuel into the engine, for example, so that the output torque from the engine becomes zero when no brake power is wanted. Another option for avoiding internal friction of the engine is to disengage the engine from the rest of the drive line by means of a clutch disposed between the engine and the gearbox. In the present context, drive line is meant to include the vehicle engine, as well as transmission components coupled to the engine, and continuing up to the drive wheels. Other controllable units which are coupled to the engine also contribute to the braking force from the engine; i.e., are added to the brake torque from the internal friction of the engine. Examples of such units are the cooling fan of the engine, the air conditioning unit of the vehicle, air compressors, generators and other accessory units coupled to the engine.
In the present disclosure, the term "friction torque of the engine" is used to denote brake torque that is obtained from the internal friction of the engine with connected units, but without any other auxiliary brakes being connected. The term "engine brakes" embraces compression brake, exhaust brake and the friction torque of the engine.
A secondary auxiliary brake, which is disposed somewhere after the main gearbox of the vehicle, is usually constituted by a retarder of the hydrodynamic or electromagnetic type. The brake power which can be delivered by a secondary auxiliary brake is dependent on the speed of the vehicle since the auxiliary brake is mounted on the output shaft of the gearbox and is therefore proportional to the rotation speed of the drive wheels.
When a vehicle is driven on a downhill slope, the brake power of the auxiliary brake may not prove sufficient, but rather the driver may instead need to support this with the service brake in order to maintain a low and regular vehicle speed. On certain occasions, the brake power from an auxiliary brake can be cut-off without the driver expecting it, which can be disquieting for the driver.
Such a situation occurs when the vehicle is being driven on a steep downhill slope at a low speed and the vehicle is equipped with a semiautomatic gearbox; i.e., an automatically shifted stage-geared gearbox. These gearboxes are often non-synchronized and the vehicle has no manual clutch pedal for disconnecting the clutch in the transmission. When the driver brakes the vehicle to reduce the speed, the engine speed will also decrease. When the engine speed approaches the idling speed of the engine, the system will disengage the gearbox; i.e., the power transmission between the engine and the transmission is broken. This disengagement is realized to prevent the vehicle from driving the vehicle forward with the aid of the idle regulator and prevent the engine from being throttled down. This means, at the same time, that the brake torque deriving from the internal friction of the engine, and any primary auxiliary brakes, disappears. The result is a sudden reduction in braking torque which can cause the vehicle to start to accelerate. This can be disquieting for the driver because he senses a reduced brake power even though he is stepping on the service brake.
There is therefore a need to be able to distribute the brake torque between service brakes and engine brakes in a vehicle in a way which compensates for the loss of brake power from the engine brakes. This is the main aim of the invention which is described below.

Method and arrangement for distributing brake torque on a vehicle


A cable assembly comprising: (a) a ribbon cable having a plurality of optical fibers having endfaces; (b) an elastomeric sheathing being disposed over at least a portion of the ribbon cable and terminating in a sheathing end near the endfaces such that the endfaces protrude beyond the sheathing end; (c) a ferrule having an mating surface presenting the endfaces, and a rear end having a rear opening through which the optical fibers pass, the rear end contacting the sheathing end to form an adhesive tight seal sufficient to prevent liquid adhesive in the ferrule from flowing out of the rear opening; and (d) adhesive disposed in the ferrule to secure the optical fibers to the ferrule.

Optical ribbon cable is used commonly to connect optical components together and is a convenient solution for applications having space and weight limitations. A conventional ribbon comprises optical fibers, which are placed side-by-side and encapsulated with a coating or a tape, for example, Mylar, to form a strip of optical fibers. A single ribbon may contain, for example, 4, 8, 12, or more optical fibers.
The advantage of utilizing ribbon fiber cables resides in the ability to achieve a much higher density in a patch panel, cable routing/ducting, and device connection environments, without compromising the quality or quantity of the connection. Because the ribbon contains only coated optical fibers, this type of cable takes up much less space than individually buffered optical fibers. As a result, ribbon cables are denser than any other cable design. They are ideal for applications where limited space is available, such as in an existing conduit that has very little room left for an additional cable.
Although ribbon cable is a good solution for high density optical applications, their absence of a buffer makes them susceptibility to abrasion, which necessitates taking certain precautions that complicate the assembly/installation process. Specifically, ribbon cable cannot rub against other objects, and, thus, in environments involving vibration, the cable must be secured with tiedowns and other mechanical means to prevent it from rubbing against other objects. The need for such tiedowns not only introduces additional steps/expense in the installation process, but also often presents challenges because a purchase point for a tiedown is not often available. Accordingly, Applicant has identified the need for an abrasion resistant ribbon cable that minimizes the need for tiedowns and other mechanical restraints. Furthermore, as the use of ribbon cables becomes more prevalent in rugged and demanding applications, such as aerospace, Applicant also identifies the need for a ribbon cable that is chemically and thermally resistant. The present invention fulfills these needs, among others.


An exemplary semiconductor device is provided. The semiconductor device includes a semiconductor stacked layer and a conductive structure. The conductive structure is located on the semiconductor stacked layer. The conductive structure includes a bottom portion and a top portion on opposite sides thereof. The bottom portion is in contact with the semiconductor stacked layer. A ratio of a top width of the top portion to a bottom width of the bottom portion is less than 0.7. The conductive structure can be a conductive dot structure or a conductive line structure.

Light-emitting diodes (LEDs) are semiconductors that are widely used in light sources. Comparing to conventional tungsten lamps or cold cathode fluorescent lamps (CCFLs), LEDs consume less power and have longer lifetime. Therefore, LEDs are replacing the conventional light sources gradually, and utilized in various fields. For example, the LEDs are capable of being employed in traffic lights, optical display devices, data storage devices, communication devices, illuminative equipments and medical equipments. The desire of brightness of the LEDs increases as the usage and development of the LEDs evolves, thus one of the main goals of engineers who design LEDs is to increase the brightness of the LEDs.
One method for enhancing brightness and luminous flux of LEDs is to enlarge surface area of a chip. However, when the surface area of the chip is enlarged, an electric current can not be spread uniformly from a contact electrode into a light-emitting layer; and if the surface area of the contact electrode is enlarged to make the electric current spread uniformly, an effect of light blocking would occur and thus the light extraction is reduced. In this regard, how to spread the electric current uniformly in the light-emitting layer and increase the brightness of the LED without changing the surface area of the contact electrode is a problem need to be solved.
A conventional method for spreading the electric current is performed by using a semi-transparent current spreading layer formed on a p-type semiconductor layer. Generally, for reducing effect of absorbing light, it is preferred to have a thinner semi-transparent current spreading layer. However, the thinner the semi-transparent current spreading layer is, the higher its sheet resistance is.
What is needed, therefore, is a semiconductor device that can overcome the above-mentioned shortcomings.


First and second polarized light beam splitters 13, 14 split non-polarized light L into p polarized light P and s polarized light S1 and allow the p polarized light P to transmit in the same direction as that of the non-polarized light L, reflecting the s polarized light S1. A light emitting apparatus 1 emits one the s polarized light and the p polarized light that are split by the first and second polarized light beam splitters 13, 14 as first vertical polarized light having a vibration plane in an electric field substantially perpendicular to the ground and converts the other of the p polarized light and the s polarized light by first and second ½ wave plates 5, 6 for converting a vibration plane in an electric field as second vertical polarized light having a vibration plane in an electric field substantially perpendicular to the ground for emission.

The present invention relates to a light emitting apparatus such as headlamps and fog lamps which are equipped on an automotive vehicle.
Further, the present invention relates to a polarized light splitting device and an automotive light emitting apparatus, and more particularly to a polarized light splitting device for splitting non-polarized light emitted from a light source into p polarized light and s polarized light and an automotive light emitting apparatus having the polarized light splitting device.
Headlamps and fog lamps equipped on a vehicle are such as to be illuminated when there occurs a situation where conditions ahead of the vehicle become difficult to be identified. For example, the headlamps are used at night or in a tunnel where surrounding conditions are invisible due to darkness, or when the vision in front gets worse due to heavy rain or thick fog.
Incidentally, in the event that the headlamps of the vehicle are illuminated at the time of thick fog or heavy rain, light emitted from the headlamps are reflected irregularly by rain drops or particles of fog, there occurs a situation where a wall of light, as it were, appears in front of the vehicle, and the vision in front is interrupted.
FIG. 14 shows a condition of light emitted from the headlamps of the vehicle at the time of thick fog or heavy rain, in which FIG. 14A is an exemplary diagram illustrating a distribution of light from the headlamps in such a condition, and FIG. 14B is an exemplary diagram illustrating an irregular reflection produced on the surfaces of rain drops at the time of heavy rain.
As shown in FIG. 14A, since light emitted from the headlamps is irregularly reflected in a complex fashion on the surfaces of fine particles of vapor or rain drops which exist on the optical paths and forms a wall of light in the vicinity of the vehicle, the driver cannot secure the vision in far front of the vehicle.
As shown in FIG. 14B, light is reflected repeatedly and in various direction on the surfaces of rain drops, and the driver feels that there appears a wall of light due to rain drops illuminated by the headlamps. In a condition like this, an object which can be identified in a normal condition cannot be identified.
Here, while rain drops falling at the time of thick fog or heavy rain are formed into a substantially spherical shape, as the particle shape becomes larger, rain drops are subjected to larger air resistance and becomes flat, whereby the surface area of such rain drops is increased. Since rain drops are fanned into such a shape, light from the headlamps which enters sideways is irregularly reflected in various ways and is then diffused in a vertical direction relative, in particular, to the ground. Furthermore, since the density of rain drops is increased at the time of thick fog or heavy rain, light irregularly reflected once by rain drops is reflected again by lots of rain drops existing in the vicinity of the original rain drops, and thus, the reflection is repeated, whereby rain drops in the whole area illuminated by light emitted from the headlamps are illuminated, so that the driver feels as if there appears a wall of light in the vicinity of the vehicle, and the vision in front of the driver is interrupted, the vision in far front of the vehicle thereby becoming difficult to be identified by the driver.
Incidentally, there exists an invention for interrupting light from headlamps by incorporating polarizer in headlamps of a vehicle (for example, refer to JP-A-61-253236 (page 2, FIGS. 1 to 3)). This invention is intended to prevent the dazzle of the driver by the headlamps in high-beam conditions, and a polarizer is incorporated in a high-beam lamp of the headlamp and a light detector is incorporated in a windscreen, so that the driver is prevented from being dazzled by high beams from an oncoming vehicle.
JP-A-61-253236 (page 2, FIGS. 1 to 3)
Further, conventionally, there are disclosed polarized light splitting devices for improving the utilization rate of light emitted from a light source by laminating alternately high refractive index films and low refractive index films (for example, refer to JP-A-9-293406 (pages 4 to 5, FIG. 1 and FIGS. 8 to 12)).
A polarized light splitting device described in JP A-9-293406 (pages 4 to 5, FIG. 1 and FIGS. 8 to 12) is a polarizing plane light source device in an image display using linear or plane polarization such as a general purpose liquid crystal display.
Here, the polarized light splitting device is such that a polarized light splitting layer is formed by two to six transparent films comprising glass as a high refractive index film, a polyester film and a polyphenol A polycarbonate film.
In addition, a light emitting apparatus fitted on an automotive vehicle such as a headlamp and a fog lamp is such as to illuminate when there occurs a situation where a condition in front of the vehicle becomes difficult to be identified by the naked eyes of the driver.
Then, in order to improve the vision in front of the vehicle by eliminating the problem, it is conceivable to adopt the polarized light splitting device described in JP A-9-293406 (pages 4 to 5, FIG. 1 and FIGS. 8 to 12) for the automotive light emitting apparatus.
Namely, it can be contemplated to improve the utilization rate of light emitted from the light source so as to brightly illuminate the front of the vehicle.
However, in the invention described in JP-A-61-253236 (page 2, FIGS. 1 to 3), since light emitted from the headlamp is cut due to the utilization of the polarizer (a polarizing filter), 50% or more of the light so emitted is lost and this reduces the utilization efficiency of headlamp light, causing a problem that the illuminated area gets dark.
Due to this, in the event that such headlamps are used at the time of thick fog or heavy rain, the illuminated area in front of the vehicle gets darker.
Namely, with the headlamps according to JP-A-61-253236 (page 2, FIGS. 1 to 3), it is not possible to illuminate brightly the area in front of the vehicle, and since the invention is not intended to cope with a case where the vision of the driver is interrupted by thick fog or heavy rain, the invention can provide no effect to improve the vision at the time of thick fog or heavy rain.
In addition, since the polarizer (the polarizing filter) has in general a low heat resistance, in the event that it is used in the headlamp, there is caused a problem that the polarizing performance of the polarizer heated by the heat of the headlamp is deteriorated drastically.
Furthermore, in a case where the light emitting apparatus is used as an automotive headlamp, due to the configuration of a location of a vehicle where the headlamp is disposed or the construction of the light emitting apparatus, there have exsisted limitations not only on the disposition of the headlamp but also on the design of vehicles.
Further, in a case, however, where the polarized light splitting device in JP A-9-293406 (pages 4 to 5, FIG. 1 and FIGS. 8 to 12) above where the high refractive index films and the low refractive index films which comprise the solids such as transparent films are laminated is used for an object which is subjected to vibration during traveling such as a vehicle, there is expected a deformation or deviation between the high refractive index film and the low refractive index film.
Consequently, since the refractive indices and the direction of reflection are changed due to such a deviation between the laminated films in the laminated layer, there is caused a problem that proper refraction and reflection of light cannot be attained, and hence, splitting into appropriate polarized light cannot be attained.
It is desired that the polarized light splitting device and the automotive light emitting apparatus equipped with the polarized light splitting device need to be maintained in a condition where enough durability to eliminate the occurrence of any deformation or deviation in position that would be caused between the high refractive index film and the low refractive index film in the polarized light splitting device by vibrations, so that proper refraction and reflection of light and splitting into appropriate polarized light can be attained at all times.


A substrate processing method that can remove a silicon nitride film without damaging a thermally-oxidized film. A substrate having at least a thermally-oxidized film and a silicon nitride film formed on the thermally-oxidized film is heated to a temperature of not less than 60° C. Then, hydrogen fluoride gas is supplied toward the substrate.

1. Field of the Invention
The present invention relates to a substrate processing method and a substrate processing apparatus, and in particular to a method of processing a substrate having a silicon nitride film and a thermally-oxidized film.
2. Description of the Related Art
Wafers as substrates are known that have a thermally-oxidized film formed on a single-crystal silicon base material, and a silicon nitride (SiN) film formed on the thermally-oxidized film. For such wafers, it may be required to remove only the silicon nitride film without removing the thermally-oxidized film.
In general, as methods of removing the silicon nitride film, wet etching using hot phosphoric acid and dry etching using plasma produced from chemical compound gas are known (see, for example, Japanese Laid-Open Patent Publication (Kokai) No. 2003-264183).
However, through the wet etching using hot phosphoric acid and the dry etching using plasma, it is difficult to secure the selective ratio of the silicon nitride film to the thermally-oxidized film, and as a result, not only the silicon nitride film but also the thermally-oxidized film may be etched, causing damage to the thermally-oxidized film.

Substrate processing method and substrate processing apparatus


In a state of a first semiconductor integrated circuit device on which a first semiconductor integrated circuit board including a first mask ROM and a programmable ROM are mounted, an ultimate program determined by using the programmable ROM is stored in a second ROM of a second semiconductor integrated circuit board which is substantially similar in structure to the first semiconductor integrated circuit board, thereby manufacturing a second semiconductor integrated circuit device as an ultimate product.

This invention relates to a method of manufacturing a single chip semiconductor integrated circuit device (a microcontroller) and a method of debugging a program of the single chip semiconductor integrated circuit device.
As well know in the art, a microcomputer is defined by a miniaturized electronic computer constituted by a microprocessor. The microprocessor is a processor wherein a central processing unit (CPU) of the computer is integrated on one or few large-scale integrated circuits (LSIs). The microcomputer normally comprises the CPU, an input/output device, and a main memory device. The main memory device comprises a random access memory (RAM) and a read only memory (ROM). An input/output control LSI is used as a connecting circuit portion for the input/output device. A single chip microcomputer is a microcomputer where the CPU, the RAM, the ROM, and the input/output LSI are mounted in a one chip. The single chip microcomputer is called a one chip microcomputer.
A program is read from an outside of a chip of the microprocessor while the program is preliminarily installed in the inside in the chip of the signal chip microcomputer. The microprocessor is capable of changing processing contents by renewing the program of the outside while it is almost impossible for the single chip microcomputer to change processing contents by a user because the program is already installed in the inside in the chip thereof. Herein, the program is preliminarily stored in the ROM.
In addition, as well know in the art, read only memories (ROMs) are broadly divided into mask ROMs wherein wiring of contents is carried out at a manufacturing process in a semiconductor maker and programmable ROMs (PROMs) where a user can electrically write with the program therein.
The mask ROMs can be manufactured at the lowest price among the semiconductor memories in principle. Therefore, products having a large memory capacity are manufactured as the mask ROMs. On the other hand, the programmable ROMs have features wherein the writing of the program can carry out by a user at hand. The programmable ROMs are classified into PROM in a narrow sense wherein the user can program only once, erasable and programmable ROMs (EPROMs) which can be electrically programmed and can be erased by ultraviolet light or the like, and electrically erasable programmable ROMs (EEPROMs).
In the EPROM, the user can program and all of data can be erased by irradiating it with ultraviolet light to be enable to rewrite therein. Inasmuch as a glass window for erasing by ultraviolet light is required in the EPROM, the EPROM is commonly contained in a ceramic package. There is a one time programmable ROM (OTP) as the EPROM in a narrow sense. The OPT comprises a semiconductor chip embedded therein that is similar to that of the EPROM but the OTP cannot be erased by ultraviolet light because the OTP comprises a package with no window. By using an ordinary EPROM programmer, the user can program information to each memory cell in the OTP only once. The OTP has a cost which is higher than that of the mask ROM and which is lower than that of the EPROM. There is a flash EEPROM as a kind of the EEROMs. The flash EEPROM is also called a flash memory which can electrically erase all of bit contents (which may erase every block) to rewrite contents therein among the programmable read only memories (PROMs).
Such a single chip microcomputer is mounted in an ordinary electric calculator, a printer, a keyboard, a microprocessor-controlled automatic (electric) rice cooker, a microprocessor-controlled camera, an engine controller for an automobile, an so on. Inasmuch as the single chip microcomputer mainly often controls operations of its equipment with it installed in the equipment, the single chip microcomputer may be called a microcontroller. In addition, the microcontroller is a kind of the single chip semiconductor integrated circuit devices.
In order to effectively carry out development of the equipment (an electronic device) in which such a single chip microcomputer (microcontroller) is installed, various development systems (development tools) are delivered by semiconductor makers or development tool makers. Inasmuch as the single chip microcomputer (microcontroller) comprises hardware and software which are closely related to each other and has a short time period of development, debug of the software and checking of the hardware must be simultaneously carried out. That is, development of the hardware and the software must often carried out concurrently. In this event, the debug of the software is required with a yet-to-be-completed hardware.
There is an emulator as one of debug tools (development tools). Herein, the emulator is a device or a computer program for imitating, by using a system, another system. With the help of the emulator, verification of functional operations of the equipment (electronic device) installed with the software is carried out. Emulators are divided into an in-circuit emulator (ICE) which is used with it directly connected to the equipment (the electronic device) under development and a software emulator using a logic simulator. That is, the in-circuit emulator is a development tool for supporting the verification of the functional operations of the equipment (electronic device) by directly connecting it to the equipment (electronic device) mounting a program-controlled microcontroller under development.
Usually, development of the hardware of the microcontroller is carried out by the semiconductor maker side while development of the software of the microcontroller is carried out by the user side. That is, development of the microcontroller is carried out by cooperative working of the semiconductor maker and the user.
Now, the description will proceed to a conventional method of manufacturing of a microcontroller. Herein, the description will be directed to the method of manufacturing, as an ultimate product, a microcontroller comprising a mask ROM in which an ultimate program is stored.
First of all, between the semiconductor maker and the user, investigation of specifications of the microcontroller (the single chip semiconductor integrated circuit device) to be manufactured is carried out. Herein, the ultimate microcontroller to be manufactured comprises a CPU, an RAM, a mask ROM, and an input/output control LSI which are incorporated into a one chip. In addition, the CPU, the RAM, the mask ROM, and the input/output control LSI are mutually connected to each other via an internal bus. The internal bus comprises an address bus and a data bus.
The semiconductor maker provides the user with the emulator (the software emulator and the in-circuit emulator) as the envelopment tool while the user develops, by using the emulator, software (a program) to be stored in the above-mentioned mask ROM.
Subsequently, the semiconductor maker designs a product in OTP version and the user carries out debug of the program using the software emulator. Herein, the product in OTP version (a provisional microcontroller) to be designed comprises a CPU, an RAM, the OTP, and an input/output control LSI which are incorporated into a one chip. In other words, the provisional microcontroller is similar in structure to the ultimate microcontroller except that the OTP is used in lieu of the mask ROM. However, any program is not stored in the OTP and storing of the program to the OTP is carried out by the user side in the manner which will later be described. The provisional microcontroller is sealed in a semiconductor package. On the other hand, carried out by the user, debug of the program using the software emulator is carried out with the hardware put into a yet-to-be-completed state.
The semiconductor maker provides the user with a plurality of the provisional microcontrollers which are similar in structure to one another. The user stores, by using the EPROM programmer (writer), a provisional program (which is a program debugged by using the software emulator) in the OTP in one selected from the plurality of the provisional microcontrollers, mounts the selected provisional microcontroller in question in an equipment (a target board), and carries out a test of the provisional program. That is, by using the above-mentioned in-circuit emulator, the user carries out verification of functional operations of the equipment (target board). In the manner which is described above, the OTP is a PROM in which information can be written only once. Accordingly, if any correction place (error) is found out in the provisional program by the test, the user stores a corrected provisional program in another provisional microcontroller, and carries out retest and re-correction of the corrected provisional program. That is, the test and the correction (the retest and the re-correction) of the provisional program is repeatedly carried out. By repeating operations of the test and the correction (the retest and the re-correction) for the provisional program, an ultimate program is determined by the user side.
On the other hand, after the provisional controllers are provided to the user, the semiconductor maker subsequently carries out design of a produce in mask ROM version. Herein, the product in mask ROM version (an actual microcontroller to be mounted in the equipment) to be designed comprises a CPU, an ROM, the mask ROM, and an input/output control LSI which are incorporated in a one chip. However, at this time instance, the ultimate program has yet to be written in the mask ROM of the actual microcontroller.
The user sends (provides) the above-mentioned determined ultimate program to the semiconductor maker. The semiconductor maker stores, using ion implantation, the ultimate program in the mask ROM of the actual microcontroller, thereby a microcontroller as the ultimate product is manufactured. In addition, the microcontroller manufactured in the manner which is described above is sealed in a semiconductor package and is produced in large quantity. And, ultimate microcontrollers produced in large quantity are provided to the user.
The user mounts the ultimate microcontrollers in the respective equipments (electronic devices), thereby the equipments are produced in large quantity.
Although the above-mentioned microcontroller comprises one semiconductor chip, U.S. Pat. No. 7,199,469 or U.S. Pat. No. 7,199,469 B2 issued to Ishida et al. discloses a semiconductor device (a microcontroller) having stacked two semiconductor chips sealed with a resin seal member. As the semiconductor device, a semiconductor device called a multi chip package (MCP) type is known. Although ones having various structures are developed and manufactured in the MCP type semiconductor devices, the MCP type semiconductor device comprising the stacked two semiconductor devices sealed with the resin seal member becomes most widespread. Ishida et al. discloses the semiconductor device wherein a chip for a microcomputer (a first semiconductor chip) and a chip for EEPROM (a second semiconductor chip) are incorporated in a package. That is, Ishida et al. discloses the semiconductor device wherein the chip for EEPROM (the second semiconductor chip) is stacked on the chip for the microcomputer (the first semiconductor chip) and the two chips are sealed with the resin seal member. The chip for the microcomputer comprises a processor unit (CPU), an ROM unit, an RAM unit, a timer unit, an A/D conversion unit, a serial communication interface unit, a data input/output circuit unit, and so on which are mounted on the same board. Those units are mutually connected through a data bus and an address bus. The processor unit mainly comprises a central processing portion, a control circuit portion, an arithmetic circuit portion, and so on. The chip for the microcomputer having such a structure is operated by a program. On the other hand, the chip for the EEPROM comprises a serial communication interface unit, a nonvolatile storage unit, and so on which are mounted on the same board. According to Ishida et al., electrical connection between the first semiconductor chip and the second semiconductor chip is carried out by internal leads among leads disposed around the first semiconductor chip and two bonding wires.
In addition, United States Patent Application Publication No. 2002/0027281 A1 or US 2002/0027281 A1 discloses a multi chip package (a semiconductor device) which is capable of controlling a rise in temperature, which occurs inside a package due to heat (self-heating) radiated from a semiconductor chip. According to US 2002/0027281 A1, the multi chip package constructing a microcontroller comprises a lower semiconductor chip on which the microcontroller including a mask ROM is formed and an upper semiconductor chip including flash memory mounted on the lower semiconductor chip. Inasmuch as no transistor is formed on the lower semiconductor chip under the upper semiconductor chip, it is possible to neglect the self-heating in this area. In addition, US 2002/0027281 A1 discloses an embodiment wherein transistors having a mask ROM function are formed on the lower semiconductor chip at a mounting area (a substantially central area) for the upper semiconductor chip and the upper semiconductor chip (the flash memory) is mounted on the mounting area. In this event, the mask ROM function in the lower semiconductor chip is discarded.
In the above-mentioned conventional method of manufacturing the microcontroller, the semiconductor maker must carry out design of two kinds of products, namely, design of a product of the OTP version and design of a product of the mask ROM version. As a result, the conventional method is disadvantageous in that it takes very much time (e.g. one year or one and half years) to develop the microcontroller as the ultimate product.
In addition, the product of the OTP version and the product of the mask ROM version are a pin-for-pin equivalent in a package state and can be substituted by each other. However, the product of the OTP version and the product of the mask ROM version are different from each other as semiconductor chips and cannot be compatible in characteristics in abundance. That is, when the product of the mask ROM version is replaced with the product of the OTP which is completed with evaluation, there are cases where a malfunction such as no operation occurs.
On the other hand, as disclosed in the above-mentioned U.S. Pat. No. 7,199,469 B2 and the above-mentioned US 2002/0027281 A1, it can be considered that a method of manufacturing, as the ultimate product, the microcontroller having the stacked two semiconductor chips sealed with the resin seal member without using one semiconductor chip. However, inasmuch as the EEPROM (the flush memory) is very expensive compared to the mask ROM, it is unsuited for a case of high volume production of the microcontrollers.
In addition, US 2002/0027281 A1 discloses the embodiment where the upper semiconductor chip (the flash memory) is mounted on the mask ROM area of the lower semiconductor chip and the mask ROM function is discarded. However, US 2002/0027281 A2 neither discloses nor teaches concrete means (structure) how to discard the mask ROM function.

Method of manufacturing a single chip semiconductor integrated circuit device including a mask ROM in a short time


A system and method for determining the appropriate downforce on an agricultural planter row unit that minimizes soil compaction while maintaining desired furrow depth. A load sensor is disposed to generate a load signal corresponding to loading on a depth regulation member of the row unit. In one method a load margin is calculated based on a minimum detected load value. In another method, a load margin is derived through a statistical analysis of the detected load values. The load margin calculated or derived by any of the methods is indicative of the amount of supplemental down force that should be increased or decreased to bring the load margin toward zero. A ground contact parameter may also be used in connection with the load margin to provide further confidence on the proper amount of downforce required to ensure furrow depth while minimizing soil compaction.

One challenge that a producer of agricultural crops faces when attempting to properly adjust the operating parameters of his planting equipment is the varying soil conditions frequently encountered during planting operations. Varying soil conditions result from differing soil types (sand, clay, or silt), differences in soil moisture, drainage and tillage practices or conditions throughout the field. In addition to varying soil conditions, different operating speeds may require different adjustments to be made to the equipment.
One operating parameter over which the operator has the most control for adjusting to varying soil conditions is the downforce applied to the planter row unit. There are two problems associated with improper downforce being applied to the planter row unit. The first problem is that excess downforce results in too much weight being carried by the depth regulating member (i.e., depth gauge wheels, skis, skids, runners etc.). Excessive weight can compact the soil surrounding the furrow and thereby inhibit proper development and growth of the roots and plant. Excessive downforce can also result in a planting depth that is too great with some types of furrow openers. The second problem is that insufficient downforce can result in a shallow furrow which can also detrimentally effect the yield as the seed may not be deep enough to have adequate moisture for proper germination.
It is generally understood that the total downforce acting on the row unit consists of the dead weight of the row unit plus the live weight of seed and/or insecticide carried upon the row unit, plus any supplemental downforce applied through the parallel arm linkage. Of the total down force for the row unit, the majority is used in forcing the opener disk(s) into the soil to the desired seeding depth. The remainder of the total down force is carried by the depth gauge wheels.
Several attempts have been made to develop a control system which measures or senses the load on the gauge wheels. One such system is disclosed in European patent EP0372901 to Baker (the "Baker '901 patent") which utilizes a displacement transducer or load cell to measure the average load on the gauge wheels over a period of time.
Another system is disclosed in U.S. Pat. No. 6,389,999 to Duello (the "Duello '999 patent) which discloses the use of a strain gauge or other sensor for measuring the average load on the gauge wheels over a period of time. The disclosure of the Duello '999 patent at least acknowledges that there will be frequent load shifts experienced by the load sensors. However, Duello '999 suggests that the loads signals should be filtered in order to avoid "constant, minute responses that may task and overwork the system." It should be understood, that when a signal is filtered as suggested by Duello '999, the resultant data trace will identify only the average value of the signal over the given time interval as opposed to identifying the actual detected signal peaks and valleys. The Duello '999 patent also suggests that some "change limit" must be exceeded before action is taken. Although it is unclear from the Duello specification, it is assumed that this change limit is a predetermined amount by which the load must change relative to the average before any action is to be taken.
Yet another system is disclosed in U.S. Pat. No. 6,701,857 to Jensen (the "Jenson '857 patent"). Jenson '857 discloses a depth control device that also measures the load on the gauge wheels where "readings are averaged and sampled every few seconds so as not to create an erratic reading." Jenson '857 speaks of a desired or predetermined load value (target load) input by the operator. A control algorithm regulates the downforce in an attempt to ensure the average downforce matches the target load as closely as possible.
While each of the forgoing systems may perform their intended purpose, it should be recognized that not all soil conditions result in the same type of gauge wheel loadings. If the operator is required to select a target load, the selected target load may be too great (resulting in soil compaction) or too little (resulting in shallow furrows) depending on the changing soil conditions. For example, highly tilled soil will be very uniform as well as very compactable, resulting in very uniform load upon the gauge wheels throughout the field. By contrast, in no till or minimum tillage systems, the soil structure will vary dramatically throughout the field. FIG. 2 illustrates the load signal generated from actual planting conditions in a field which was highly tilled and had a uniform soil type. The average load was approximately 100 pounds and the signal deviated little from this value, never falling lower than 85 pounds or rising greater than 115 pounds. FIG. 3 illustrates the load signal from a minimum tillage field where the load was varying dramatically. The average load was approximately 150 pounds but dropped nearly to zero and rose as high as 300 pounds at times. These two scenarios show the different characteristics of gauge wheel loadings that prevent an operator from making the best determination of downforce setting based solely on average load alone. Thus, the aforementioned systems fail to provide the necessary information to the operator or an automatic control actuator to minimize excess soil compaction while at the same time avoiding loss of proper furrow depth.
The proper downforce for any given planting condition should be that amount of downforce required to maintain the desired furrow depth without imparting excessive compaction to the soil surrounding the furrow. Balancing these two criteria is difficult because, as explained above, minimizing compaction will tend to create a loss of furrow depth, whereas minimizing loss of furrow depth will tend to increase compaction. Accordingly, there is a need for a system and method for determining the proper downforce for planter row units that will ensure desired furrow depth while minimizing soil compaction.

System and method for determining proper downforce for a planter row unit


A cryostat for a superconducting magnet system is provided. The cryostat may include an outer vessel and an inner vessel suspended within the outer vessel. A space may be defined by the outer vessel and the inner vessel. The cryostat may include multiple first support elements and one or more second support elements. The strength of the first supporting element may be larger than that of the second support elements. The inner vessel and the outer vessel may be connected by two opposite ends of a first support element and two opposite ends of a second support element, respectively. The number of the first support elements in the lower part of the space is different from the number of the first support elements in the upper part of the space.

Magnetic resonance imaging (MRI) is widely used in the medical imaging field. When an object, e.g., a human body, is placed in a main magnetic field, the hydrogen atoms in the object may be polarized. A pulse of radio-frequency (RF) may excite hydrogen atoms in the object, causing the hydrogen atoms to resonate and absorb energy. When the RF pulse is removed, the hydrogen atoms may emit a RF signal with a certain frequency, and release at least part of the energy absorbed. A receiver placed outside the object may receive the emitted RF signal, based on which a magnetic resonance (MR) image may be produced.
MRI may produce images in, for example, the traverse plane, the sagittal plane, the coronal plane, or other planes essentially without an adverse impact on an object by exposing the object to radiation.
A magnet is a component in a magnetic resonance imaging system to produce a stable magnetostatic field. Superconducting magnets are widely used in MRI systems. The basic principle is to immerse one or more coils formed by a superconducting material in liquid helium at an extremely low temperature (about 4K), then to energize to coils to produce a magnetic field. The liquid helium and the coils may be held within a cryostat. Liquid helium is expensive and volatile, and so it is desirable to thermal isolate the interior from exterior ambient temperature condition to reduce boiling off helium.
FIG. 1A through FIG. 1D show a traditional cryostat, which has a multi-layer structure. FIG. 1A is a front view partly in section of a traditional cryostat, FIG. 1B illustrates the internal multiple layers structure and the connection of the traditional cryostat, FIG. 1C is a simplified schematic structure diagram of the traditional cryostat, and FIG. 1D is a side view of FIG. 1C. As shown in FIG. 1A through FIG. 1D, the cryostat includes an outer vessel 110 and an inner vessel 120. The inner vessel 120 may be configured to hold a cryogenic medium. One thermal shielding layer 130 may be employed between the inner vessel 120 and the outer vessel 110. The inner vessel 120 and the thermal shielding layer 130 are supported spaced apart from one another with multiple support elements within the outer vessel 110. The suspension support elements include multiple support elements 140 (represented by lines with black dot ends) placed radially and multiple support elements 150 (represented by lines with black triangle ends) placed axially. As shown in FIG. 1B, the support elements 150 placed axially may be a rod. The support elements 140 and the support elements 150 should be strong enough to withstand the gravity of the inner vessel 120, as well as the shock load during transportation, or a combination thereof. The shock load may be multiple times of the gravity of the inner vessel 120. Some extra preload may be applied to the support elements in advance to prevent tension losing at a low temperature. In this kind of cryostat embodiment the force of the suspension system is relatively simple and could be calibrated easily, but the number of support elements is large. Merely by way of example, there may be sixteen support elements, including eight support elements 140 placed radially and eight support elements 150 placed axially (as shown in FIG. 1C and FIG. 1D, because the traditional cryostat may be a symmetrical system, part of the support elements may overlap in the front view and the side view of the cryostat). The large number of support elements may result in a complicated system, a cumbersome assembly process, and high cost. Moreover, a large number of support elements may import more heat load into the inner vessel, which would degrade the stability of the thermal system and more cryogen loss.

This patent is subject to a terminal disclaimer.

Cryostat for superconducting magnet system

SHANGHAI UNITED IMAGING HEALTHCARE CO., LTD.


An image recording/reproducing apparatus and a control method thereof to provide the functions of recording image files in a recording medium and reproducing and editing the image files recorded in the recording medium. The apparatus and method enables a user to easily select and manipulate functions of the apparatus using a menu display, and can record, reproduce and edit the image files according to the function selected by the user. The apparatus and method, therefore allows the user to easily select and manipulate the functions using a displayed menu, and more efficiently manage and easily search for the recorded image files.

1. Field of the Invention
The present invention relates to an image recording/reproducing apparatus and a control method thereof which provide functions of recording image files in a recording medium, and reproducing and editing the image files recorded in the recording medium, and more particularly, to an image recording/reproducing apparatus and a control method thereof which enables a user to easily select and manipulate functions of the apparatus using a menu display, and which can record, reproduce and edit the image files according to the function selected by the user.
2. Description of the Related Art
An image recording/reproducing apparatus records image files in a recording medium and also reproduces the recorded image files. A few examples of such an image recording/reproducing apparatus are video cassette recorders (VCR) and digital video disc players (DVDP).
Recently, with the development of the technologies in image signal processing and compression, the use of mass entertainment media has been shifted from audio media to video media with the increasing use of the image files. The number of image files which are recorded in image recording/reproducing apparatus therefore, have increased, and the scheme of managing the recorded image files more efficiently and searching for the image files more easily has now become a matter of primary concern.
Also, as the electronic appliance becomes multifunctional, the image recording/reproducing apparatus has become more complicated and multifunctional. Accordingly, a need exists for a system and method to select and use diverse functions provided in the image recording/reproducing apparatus more easily.

Image recording/reproducing apparatus and control method thereof


First and second cylindrical housings coaxially aligned relative to one another are pivotally secured together by associated strap portions to receive a bottle therethrough, wherein the bottle structure is arranged for receiving a support strap therethrough.

1. Field of the Invention
The field of invention relates to container support structure, and more particularly pertains to a new and improved container transport assembly wherein the same is arranged for the ease of transport and securement of a container within the organization.
2. Description of the Prior Art
Container transport structure to secure a container is set forth in the prior art indicated by the U.S. Pat. No. 4,955,572 having a cylindrical housing with an end cap removable therefrom to receive a fluid therewithin.
The instant invention attempts to overcome deficiencies of the prior art by providing for a flexible aligned plurality of cylindrical housing structures arranged for ease of accommodation of a container and in this respect, the present invention substantially fulfills this need.


A laminated radiation member includes a radiation plate, an insulation substrate bonded to the upper surface of the radiation plate and an electrode provided on the upper surface of the insulation substrate. The laminated radiation member is made by a method including the steps of surface treating a bonding surface of the radiation plate and/or the insulation substrate, interposing ceramic particles surface treated to assure wettability with a hard solder or a metal between the radiation plate and the insulation substrate, disposing a hard solder above and/or below the ceramic particles, heating the hard solder to a temperature higher than the melting point of the solder, penetrating the molten hard solder into spaces between the ceramic particles to react the ceramic particles with the solder to produce a metal base composite material, and bonding the radiation plate and the insulation substrate with the metal base composite material.

The present invention relates to a laminated radiation member, a power semiconductor apparatus, and a method for making the same.
A known power semiconductor apparatus is, for example, one which is composed of the main part as shown in FIG. 4. In FIG. 4, 101 indicates a power semiconductor apparatus, 102 indicates a semiconductor chip comprising IGBT or the like, 103 indicates a metal base plate for radiating the heat generated from the semiconductor chip 102, 104 indicates a ceramic plate comprising aluminum nitride or the like for insulating the semiconductor chip 102 from the metal base plate 103, 105a indicates a first metal electrode provided above the upper surface of the ceramic plate 104, 105b indicates a second metal electrode provided below the lower surface of the ceramic plate 104, 106a indicates a first hard solder paste for bonding the ceramic plate 104 to the first metal electrode 105a, 106b indicates a second hard solder paste for bonding the ceramic plate 104 to the second metal electrode 105b, 107a indicates a first solder for bonding the semiconductor chip 102 to the first metal electrode 105a, 107b indicates a second solder for bonding the metal base plate 103 to the first metal electrode 105b, 108a indicates a first metal wire comprising aluminum to be connected to the semiconductor chip 102, 108b indicates a second metal wire comprising aluminum to be connected to the first metal electrode 105a, and 109 indicates a silicone gel which covers the semiconductor chip 102, the ceramic plate 104, the first metal electrode 105a and the second metal electrode 105b and seals them.
The conventional power semiconductor apparatus having the above construction is usually made by the following method. In the case of making the conventional power semiconductor apparatus 101, first, hard solder pastes, which are the first and second hard solder pastes 106a and 106b, are printed at a given thickness on both surfaces of the ceramic plate 104. Then, two metal electrodes, which are the first and second metal electrodes 105a and 105b, are put on the hard solder pastes printed on both the surfaces of the ceramic plate 104 and heat treated at a given temperature, for example, about 850xc2x0 C., thereby bonding the first and second metal electrodes to both surfaces of the ceramic plate 104.
Thereafter, the ceramic plate 104, to both surfaces of which the metal electrodes are bonded is bonded, to the metal base plate 103 with a high-temperature solder (melting point: about 260xc2x0 C.) which is the second solder 107b, and the semiconductor chip 102 is bonded with a low-temperature solder (melting point: about 150xc2x0 C.), which is the first solder 107a, to both surfaces of the ceramic plate 104 on which the metal electrodes are bonded. A metal wire, which is the first metal wire 108a, is connected to the semiconductor chip 102 by wire bonding, and a metal wire, which is the second metal wire 108b, is connected to the metal electrode which is the first metal electrode 105a by wire bonding.
Usually, the metal base plate 103 on which the semiconductor chip 102, the ceramic plate 104, the first metal electrode 105a and the second metal electrode 105b, and the like are mounted is contained in a package. Silicone gel 109 is vacuum injected into the package and cured by heating, whereby the semiconductor chip 102, the ceramic plate 104, the first metal electrode 105a and the second metal electrode 105b, and the like are covered with the silicone gel 109 and sealed. In this way, the conventional power semiconductor apparatus 101 is made.
However, since the insulation substrate (104) and the metal electrodes (105a,b) are bonded with the hard solders (106a,b), cracks occur due to the difference in expansion coefficient between the insulation substrate, which has a low thermal expansion coefficient, and the hard solders and metal electrodes, which have high thermal expansion coefficients. Furthermore, since the insulation substrate (104) and the radiation plate (103) are connected with solder, there is the problem of high thermal resistance.
On the other hand, as an example of using no solder for bonding of an insulation plate and a radiation plate, JP-A-11-269577 proposes a method of forming a metal base composite material having a heat sink function by a chemical process utilizing a reaction between a ceramic dispersion material and a molten metal. This method suffers from the problem that since the molten metal is high-pressure injected into the ceramic dispersion material, expensive facilities are required, causing an increase of cost. There may be considered a means to carry out the reaction under impregnating the ceramic dispersion material with molten metal, but in this case, there is the problem that the penetrating speed is slow. In this method, the insulation substrate and the metal base composite material as a radiation plate are connected with a metal film or are connected with disposing a compound containing a firing aid for the insulation substrate at the bonded surface between the insulation substrate and the metal film, and therefore the thermal conductivity is better than the case of connecting with a solder. However, occurrence of cracks caused by difference in thermal expansion coefficient between the insulation plate of low thermal expansion coefficient and the metal film of high thermal expansion coefficient or the metal film provided with a compound containing firing aid for the insulation substrate cannot sometimes be avoided.
As an example of using no metallic radiation plate, there is, for example, an aluminum-silicon carbide composite material known as a metal ceramics composite material. This composite material is generally prepared by making a molded body (preform) of ceramic particles, ceramic fibers, whiskers, etc., then impregnating the preform with a molten metal and cooling it. As the method for impregnating with molten metal, there are various known methods such as a method based on powder metallurgy, a method according to high-pressure casting, e.g., die casting (JP-A-5-508350), a melt forging method (xe2x80x9cMaterial,xe2x80x9d Vol.36, No. 1, 1997, pages 40-46), spontaneous penetrating method (JP-A-2-197368), etc.
On the other hand, as power semiconductor apparatuses, there are known, for example, those which comprise a semiconductor chip comprising IGBT or the like, a metal base plate of about 4 mm thick comprising copper or the like for radiating heat generated from the semiconductor chip, and a ceramic plate of about 0.6 mm thick comprising aluminum nitride or the like for insulating the semiconductor chip from the metal base plate. A first metal electrode of about 0.4 mm thick comprising copper or the like is bonded to the upper surface of the ceramic plate with a first hard solder of a given thickness. A semiconductor chip is bonded to the upper surface of the metal electrode with a solder of about 0.2 mm thick. A second metal electrode of about 0.2 mm thick comprising copper or the like is bonded to the under surface of the ceramic plate with a second solder of a given thickness. The under surface of the ceramic plate and the second metal electrode are bonded to the radiation plate with a solder or a hard solder.
However, there is a problem of low radiation property because the insulating ceramic substrate and the radiation plate are connected with a solder. Moreover, in the case of bonding the insulating ceramic substrate and the metallic heat sink material with a hard solder by active metal method or the like, cracks caused by thermal stress at the time of bonding occur on the side of the insulating ceramic substrate because of the great difference in thermal expansion coefficient between both the materials. Furthermore, a multi-layer type bonded body, which is bonded with a solder and provided with a stress relaxing layer by a means other than soldering, is low in endurance when exposed to thermal cycles of cooling-heating and, besides, increases in thermal resistance due to the increase of bonded interfaces which inhibits radiation. Moreover, since stress relaxation is conducted by employing a multi-layer structure, the number of production steps necessarily increases, and, as a result, this causes an increase of production cost. This is a serious problem.
On the other hand, as a method of bonding different members, the applicant of the present application disclosed in application JP-A-11-228245, utilizing an adhesive composition comprising ceramic fine particles and a hard solder and capable of reducing thermal stress. However, the object of the invention disclosed in the above application is to inhibit the decrease of bonding strength and the occurrence of cracks during the cooling operation, mainly after bonding, in making members by bonding the different members and need airtightness. The patent application makes no mention which suggests improvement of endurance in a use environment, such as increasing peeling resistance and effectively inhibiting cracking at bonded portions under severe thermal cycles, where high temperature-low temperature with cooling operation is repeated many times, in applications such as heat sinks, laminated radiation members and power semiconductor apparatuses. That is, of course, the application does not have descriptions suggesting that the products can function as a bonding layer of heat sinks, laminated radiation members and power semiconductor apparatuses.
As mentioned above, the object of the present invention is to provide a laminated radiation member as a power semiconductor apparatus which is substantially free from cracks generated due to a difference in the thermal expansion coefficient between an insulation substrate and a radiation plate, and which is excellent in radiation properties and thermal cycle characteristics, and a method for making the laminated radiation member.

Laminated radiation member, power semiconductor apparatus, and method for producing the same


The present invention provides a pharmaceutical composition which is useful as a phosphatidylinositol 3 kinase (PI3K) inhibitor and an antitumor agent, and it provides a novel bicyclic or tricyclic fused heteroaryl derivative or a salt thereof which possesses an excellent PI3K inhibiting activity and cancer cell growth inhibiting activity.

Phosphatidylinositol (hereinafter abbreviated as "PI") is one of phospholipids in cell membranes. In recent years it has become clear that PI plays an important role also in intracellular signal transduction. It is well recognized in the art that especially PI (4,5) bisphosphate (PI(4,5)P2) is degraded into diacylglycerol and inositol (1,4,5) triphosphate by phospholipase C to induce activation of protein kinase C and intracellular calcium mobilization, respectively [M. J. Berridge et al., Nature, 312, 315 (1984); Y Nishizuka, Science, 225, 1365 (1984)].
Turning back to the late 1980s, PI3K was found to be an enzyme phosphorylate the 3-position of the inositol ring of phosphatidylinositol [D. Whitman et al., Nature, 332, 664 (1988)].
PI3K was originally considered to be a single enzyme at the time when PI3K was discovered. Recently it was clarified that a plurality of subtypes are present in the PI3K. Three classes of PI3Ks have now been identified on the basis of their in vitro substrate specificity [B. Vanhaesebroeck, Trend in Biol. Sci., 22, 267 (1997)].
Substrates for class I PI3Ks are PI, PI(4)P and PI (4,5)P2, in these substrates, PI(4,5)P2 is the most advantageous substrate in cells. Class I PI3Ks are further divided into two groups, class Ia and class Ib, in terms of their activation mechanism. Class Ia PI3Ks, which include PI3K p110α, p110β and p110δ subtypes, are activated in the tyrosine kinase system. Class Ib PI3K is a p110γ subtype activated by a G protein-coupled receptor.
PI and PI(4)P are known as substrates for class II PI3Ks but PI(4,5)P2 is not a substrate for the enzymes of this class. Class II PI3Ks include PI3K C2α, C2β and C2γ subtypes, which are characterized by containing C2 domains at the C terminus, implying that their activity will be regulated by calcium ions. The substrate for class III PI3Ks is PI only. A mechanism for activation of the class III PI3Ks is not clarified yet. Since each subtype has its own mechanism for the regulating activity, it is considered that the respective subtypes will be activated depending on their respective stimuli specific to each of them.
In the PI3K subtypes, the class Ia subtype has been most extensively investigated to date. The three subtypes of class Ia are hetero dimers of a catalytic 110 kDa subunit and regulatory subunits of 85 kDa and 55 kDa. The regulatory subunits contain SH2 domains and bind to tyrosine residues phosphorylated by growth factor receptors with a tyrosine kinase activity or oncogene products thereby inducing the PI3K activity of the p110 catalytic subunit. Thus, the class Ia subtypes are considered to be associated with cell proliferation and carcinogenesis. Furthermore, the class Ia PI3K subtypes bind to activated ras oncogene to express their enzyme activity. It has been confirmed that the activated ras oncogene is found to be present in many cancers, suggesting a role of class Ia PI3Ks in carcinogenesis.
As explained above, PI3K inhibitors are expected to be a novel type of medicaments useful against cell proliferation disorders, especially as carcinostatic agents. As for the PI3K inhibitor, wortmannin [H. Yano et al., J. Biol. Chem., 263, 16178 (1993)] and LY294002 [J. Vlahos et al., J. Biol. Chem., 269, 5241 (1994)] which is represented by the formula below are known. However, development of PI3K inhibitors having a more potent cancer cell growth inhibiting activity is desired.

Japanese Patent KOKAI (Laid-Open) No. 6-220059 discloses fused heteroaryl derivatives shown by formula (a) below which possess an activity of reducing the blood glucose level. Furthermore, compounds shown by formula (b) and formula (c) below are described in Indian J. Chem., Sect. B (1993), 32B (9), 965-8 and J. Heterocycl. Chem. (1992), 29 (7), 1693-702, respectively. In addition, Al-AzharBull. Sci. (1992), 3(2), 767-75 discloses a compound shown by formula (d) below. However, none of these prior art publications disclose or suggest the PI3K inhibiting activity.

In formula (a) above, Z is O, S or ═N—R0, R1 is an amino which may be substituted, a heterocyclic group which may be substituted, etc.; R2 is cyano, an amino which may be substituted, or a heterocyclic group which may be substituted; and with respect to the remaining substituents, see the specification of the patent. In formula (b) and (c) above, R is a (substituted) amino or a (substituted) nitrogen-containing saturated heterocyclic group.
Publication No. WO98/23613 discloses fused pyrimidine derivatives, such as 7H-pyrrolo[2,3-d]pyrimidine derivatives, which having a tyrosine kinase receptor inhibiting activity and which are useful as carcinostatic agents, wherein the fused pyrimidine derivatives have at its fourth position a particular-heteroaryl-substituted amino, phenyl-substituted amino, or indole-1-yl, and have no substituent at its second position.
Following compounds are known among the compounds shown by general formula (I), whereas "A" ring is a ring shown by (b);
(1) Ann. Pharm. Fr. (1974), 32(11), 575-9 discloses 4-(4-morpholinyl)-2-phenylpyrido[2,3-d]pyrimidine as a compound having antiinflammatory and spasmolytic activities,
(2) Chem. Pharm. Bull. (1976), 24(9), 2057-77 discloses 4-(4-morpholinyl)-2-phenylpyrido[2,3-d]pyrimidine-7(1H)-one as a compound having a diuretic activity,
(3) Khim.-Farm. Zh. (1993), 7(7), 16-19 and Khim. Geterotsiki. Soedin. (1971); 7(3), 418-20 disclose 4-(4-morpholinyl)-2-phenyl-6-quinazolinol and 6-methoxy-4-(4-morpholinyl)-2-phenylquinazoline as compounds having an antibiotic activity,
(4) Publication No. WO2000/41697 discloses 2,4-diamino-6-phenyl-8-piperidinopyrimido[5,4-d]pyrimidine as a compound having cerebral ischemia prevention and treatment effects,
(5) Publication No. WO99/32460 discloses, as cardiovascular drugs, compounds of general formula (Ib) described hereinafter wherein B is a benzene ring, W is N, n is 2 or 3, existing R1's are all —OMe, and R4b is an unsubstituted phenyl or a phenyl substituted by 1 to 3 substituents which are selected from -a halogen, NO2, -a lower alkyl, —O-a lower alkyl, -a halogenated lower alkyl and —CONRaRc,
(6) Publication No. BE841669 discloses, as antiparasitics, compounds of general formula (Ib) described hereinafter wherein B is a benzene ring, W is N, n is 1, R1 is -a halogen or -a lower alkyl, and R4b is -(an imidazolyl which may have one or more substituents),
(7) Publication No. WO99/43682 discloses, as antianxiety agents, compounds of general formula (Ib) described hereinafter wherein B is a thiophene ring, and W is CH,
(8) Japanese Patents KOKAI (Laid-Open) Nos. 62-10085 and 61-158983 disclose compounds of general formula (Ib) described hereinafter wherein B is an imidazole ring, and W is N, whereas the compounds have an antiinflammatory activity, a platelet aggregation inhibiting activity, etc.,
(9) U.S. Pat. No. 3,873,545 and Act Pol. Pharm. (1994), 51(4-5), 359-63 disclose compounds of general formula (Ib) described hereinafter wherein B is a pyridine ring, and R4b is an unsubstituted phenyl, an unsubstituted pyridyl, or -a lower alkylene-(a nitrogen-containing saturated heterocyclic group which may have one or more substituents), whereas the compounds have a spasmolytic, diuretic or hypotensive activity,
(10) U.S. Pat. No. 2,940,972 discloses compounds of general formula (Ib) described hereinafter wherein B is a pyrazine ring, and R4b is an unsubstituted phenyl, or a benzyl, whereas the compounds have a coronary dilating or sedative activity,
(11) U.S. Pat. No. 3,753,981 and German Patent Publication No. 2,140,280 disclose compounds of general formula (Ib) described hereinafter wherein B is a benzene ring, and R4b is a styryl or 2-(5-nitro-2-furyl)vinyl, whereas the compounds have an antiinflammatory or antibiotic activity, and
(12) Eur. J. Med. Chem. (1996), 31(5), 417-425, discloses compounds of general formula (Ib) described hereinafter wherein B is a benzene ring, W is CH, and R2 and R3 are bonded together with an adjacent N atom to form -(piperidinyl which may have one or more substituents) or -(piperazinyl which may have one or more substituents), as compounds working as a benzodiazepine receptor ligand, U.S. Pat. No. 4,560,692 discloses them as those having a spasmolytic and ataractic activity, and Japanese Patents KOKAI (Laid-Open) No. 2-129169 discloses them as those having a lipoperoxidation inhibiting activity.
Furthermore, compounds of general formula (Ib) described hereinafter wherein B is a pyridine ring and n is 0 are disclosed in Japanese Patent KOKAI (Laid-Open) No. 51-138689 (antiparasitics), Japanese Patent KOKAI (Laid-Open) No. 56-120768 (a dye component for thermosensitive recording materials), Antimicrob. Agents Chemother., (1975), 8 (2), 216-19 (an antibacterial activity), Cancer Res. (1975), 35 (12), 3611-17 (a mutagenic activity), CA 64: 19608c, Collect. Czech. Chem. Commun., (1994), 59 (6), 1463-6, U.S. Pat. No. 5,304,554 (an anti-HIV activity), Chem. Pharm. Bull., (1982), 30(6), 1974-9, and J. Heterocycl. Chem. (1980), 17(5), 1029-34. However, none of the prior publications teach or even suggest the PI3K inhibiting activity and carcinostatic activity.

Imperial Cancer Research Technology Ltd.


A digital receiver automatically detects and non-coherently demodulates a multiplicity of interfering digitally modulated signals transmitted simultaneously at approximately the same carrier frequency. The receiver includes one or more antenna inputs (e.g., polarization and/or space diverse), a parameter estimator module, and a multiuser detector for estimating the data transmitted by each interfering signals and adapted to operate with at least one of a MUD algorithm with partially quantized prior information and a MUD algorithm based on prewhitened data.

Wireless networks are employed for communication between various devices, such as cell phones and computers. Digitally modulated signals such as binary phase shift keyed and quadrature phase shift keyed signals are transmitted between nodes of the network. Examples include satellite communications networks where terminals transmit through satellite transponders, terrestrial systems where terminals transmit through repeating towers, and indoor local area networks where terminals transmit through central repeating elements.
Computer elements connected to these networks provide a variety of user services. Examples include telephone traffic with digital voice encoding, video conferencing, wide area computer network connectivity, and internet service. In such applications, it is desirable to maximize the network traffic capacity in a given bandwidth in the presence of interference and noise.
To that end, a variety of schemes exist for efficiently partitioning the network elements into communication channels. For example, frequency domain multiple access (FDMA) schemes assign each network terminal to a separate, non-overlapping frequency band. Time domain multiple access (TDMA) schemes assign each terminal to a separate non-overlapping time slot. Code division multiple access (CDMA) schemes assign each terminal to a separate modulating waveform so that the cross correlation between each terminal is negligible.
Such schemes are inefficient in that given sufficient signal to noise ratio or coding redundancy, more communicators could use the allocated bandwidth if provided with a means for detecting the excess signal margin, as well as a means for demodulating signals in the presence of interference. In short, despite the advancements in wireless transmission and reception, conventional systems do not properly account for the real world wireless communication signals that suffer from signal degradation such as interference and multipath problems.
More specifically, a real world multiuser system includes a number of independent users simultaneously transmitting signals. Each of these transmissions are associated with real-time problems of multipath and co-channel interference that manifest in the received signals. Multipath occurs when a signal proceeds to the receiver along not one but many paths so that the receiver encounters echoes having different and randomly varying delays and amplitudes. Co-channel interference refers to signals received from other users.
A multiuser detection (MUD) receiver can be used to jointly demodulate co-channel interfering digital signals. In general, MUD refers to the detection of data in non-orthogonal multiplexes. MUD processing increases the number of information bits available per chip or signaling dimension for interference limited systems. Optimal MUD based on the maximum likelihood principle operates by comparing the received signal with the entire number of possibilities that may have occurred at the ensemble of transmitters, to give rise to the waveform received at the receiver.
However, for multiuser detectors that examine a larger capacity of signal, the computations are complex and time-consuming, thus making real-time operation impractical. Reduced complexity approaches based on conventional tree-pruning algorithms help to some extent. However, performance of such multiuser detection algorithms degrades as the parameter M (pruning factor) is decreased, but M governs the number of computations required. Thus, to combat improper pruning, basic tree-pruning must ensure that M is large enough. As a result, conventional pruning methods are still associated with increased complexity, particularly when the number of interfering signals is moderate to large.
What is needed therefore are techniques for allowing multiple users to operate in the same communication channel. Such techniques should accurately separate co-channel signals and reduce complex processing.

Bae Systems Information and Electronic Systems Integration INC


A berry harvester movable along berry bushes in a berry field for picking berries includes a rake head having a plurality of spaced apart rake teeth. The rake teeth form a rake having a top face for collecting berries and a bottom face which faces a ground of the berry field in a harvesting position. A cleaner is mounted on the rake head and is juxtaposed to a bottom face of the rake and has protrusions extending in interspaces defined between the rake teeth from the bottom face towards the top face.

Berry harvesting, particularly blueberry harvesting, is often performed by hand-picking or by raking through the berry bushes. This is a tedious work particularly for wild blueberries, which bushes barely extend a couple of centimeters above the ground.
Over the years, mechanical harvesters have been proposed to increase the speed or efficiency at which the harvesting is performed. Generally, such mechanical harvesters comprise a rake for raking the bushes, a collector for receiving and collecting the berries as they are detached from the bushes by the rake, and a transporting mean such as a conveyor for transporting the berries from the collector to a container. In order to increase efficiency, mechanical harvesters usually have the capacity to move along the berry field, in order to pick up berries in most or all of the bushes.
Current mechanical harvesters usually advance over a row of berry bushes while raking the branches of the bushes. This raking movement involves a sliding of the branches between the teeth of the rake under the movement of the harvester. Since the space between the rake teeth is usually smaller that the mean diameter of a berry, the berries are retained on the rake. Their transfer towards the collector is usually made by tilting up the rake, orienting it substantially vertically so that gravity will pull the berries toward the base of the rake, where the collector can collect them before they are move toward the transporting mean.
While such harvesters are efficient in harvesting low bushes such as wild blueberry bushes, one problem is that the rake must be periodically cleaned to remove the bush debris, such as broken branches, leaves and berries, that stuck in between the teeth during operation. Without periodical cleaning during harvesting, such bush debris are accumulating between the rake teeth, reducing the efficiency of the raking and the harvesting.
One way to perform the periodical cleaning of the rake's teeth during harvesting is by adding a slidable cleaning bar to the rake portion of the harvester. Such cleaning bar is mounted over the rake, and usually adapted to slidably move from the base to the end of the teeth of the rake. Gravity ensure that the cleaning bar will stay in contact with the rake teeth underneath it during the sliding movement. However, while such a cleaning of the rake teeth is improving the subsequent raking of further bushes, it results in the loss of valuable berries that will either be squashed or fall on the ground as a result of the sliding action of the cleaning bar. Therefore, the cleaning of the rake causes an appreciable loss of berries, while improving the global harvesting process by periodically ensuring that the rake is clean for raking through the bushes. Still, it would be highly desirable to have a system allowing for the collection of a maximum of berries, while reducing the loss of berries to a minimum, thereby optimizing the mechanized harvesting process.

Apparatus and method for picking up berries


A method for subjecting a compound [A] having a hydroxyl group or a primary or secondary amino group and a compound [B] having a substituent containing a phosphorus atom to a condensation reaction to prepare a compound [C] represented by the following general formula [C]:

A solid-phase method and a liquid-phase method are known as methods for preparing an oligonucleic acid compound. The solid-phase method is a heterogeneous reaction method in which a nucleic acid is extended while a substrate supported on a solid-phase carrier is brought into contact with a solution containing a reaction reagent. In the solid-phase method, a so-called batch method is used in which a reaction vessel with a filter is used and a reaction is carried out in the vessel (see, for example, NON-PATENT DOCUMENT 1 and PATENT DOCUMENT 1). In addition, a pseudo-flow synthesis method is also known in which, as in an automatic nucleic acid synthesizer (for example, DNA, RNA synthesizer), a solid-phase carrier is placed in a column and a solution containing a reaction reagent is passed through the column to cause a reaction.
Meanwhile, the liquid-phase method is a homogeneous reaction method in which a nucleic acid is extended by causing a reaction in a solution containing both a substrate and a reaction reagent. In the liquid-phase method as well, a batch method in which a reaction is carried out in a vessel is used (see, for example, PATENT DOCUMENT 2 and PATENT DOCUMENT 3).
In any of the cases of the solid-phase method, the liquid-phase method, the batch method, and the pseudo-flow synthesis method, in a chemical synthesis method for an oligonucleic acid compound, a nucleic acid is extended by repeating many times a "deprotection" reaction for removing a protective group for an oxygen atom or amino group on a nucleic acid compound, and a "condensation" reaction for forming a bond between a phosphorus atom and an oxygen atom or nitrogen atom deprotected to be enabled to react.
Among them, controlling the reaction efficiency or the reaction rate in the "condensation" reaction for forming a bond between a phosphorus atom and an oxygen atom or nitrogen atom is very important in the preparation of an oligonucleic acid compound, and the conditions of this condensation reaction are factors that have a great impact on the preparation period of the oligonucleic acid compound.
Since the solid-phase method is a heterogeneous reaction between a solid-phase carrier and a solution, it is known that the reactivity of the condensation reaction decreases due to steric hindrance caused by the solid-phase carrier. Polystyrene resin is generally used as the solid-phase carrier. During the reaction, the polystyrene resin swells due to the reaction solvent used, and its volume becomes larger than that in a dry state. The degree of swelling depends on the reaction solvent.
Therefore, the reaction efficiency and the reaction rate of the condensation reaction in the solid-phase method depend on the reaction solvent used. In particular, with a polar solvent such as acetonitrile, which is generally used for the synthesis of oligonucleic acid compounds, the degree of swelling of the polystyrene resin is not so high, so that the use of a polar solvent in the solid-phase method is not preferable from the viewpoint of improving the reaction efficiency and the reaction rate of the condensation reaction.
Meanwhile, as a homogeneous reaction method, a liquid-phase method and a synthetic method using a hydrophobic group-binding nucleoside, a pseudo-solid phase-protected nucleoside, or the like are known.
The liquid-phase method is a homogeneous reaction method in which a reaction is carried out in a solution containing both a substrate and a reaction reagent, and the reaction efficiency is higher than that of the solid-phase method, and the reaction rate is faster than that of the solid-phase method. However, column purification, etc., are required to remove the reaction reagent and a reaction solvent that are to be impurities.
Similar to the liquid-phase method, in the synthetic method using a hydrophobic group-binding nucleoside, a pseudo-solid phase-protected nucleoside, or the like, a reaction can be carried out in a homogeneous system, and thus the reaction efficiency is higher than that of the solid-phase method, and the reaction rate is faster than that of the solid-phase method. Furthermore, after the reaction, unnecessary reaction reagent and reaction solvent can be removed by precipitating the target compound from the reaction mixture (see, for example, PATENT DOCUMENT 4).
In these homogeneous reaction methods, a non-polar solvent such as chloroform is used in a condensation reaction. However, for example, as reported in the synthesis of a morpholino nucleic acid (see, for example, PATENT DOCUMENT 5), the condensation reaction in the non-polar solvent requires a very long time, so that the use of a non-polar solvent in the homogeneous reaction is not preferable from the viewpoint of improving the reaction efficiency and the reaction rate of the condensation reaction.

Method for preparing oligonucleic acid compound

Abstract: wherein the condensation reaction is carried out in a mixed solvent containing a polar solvent and a halogen solvent as a reaction solvent.


A method and apparatus are for surface finishing of pieces obtained by 3D printing. The piece to be treated and a liquid process plasticizer are heated together in a hermetically sealed treatment chamber up to a working temperature lower than the boiling temperature of the process plasticizer. The air/vapor mixture is maintained in continuous circulation in the chamber to keep the temperature and concentration uniform and to contact the piece with the air/vapor mixture to avoid condensate formation on the piece surface and allow process plasticizer vapors to be absorbed by the piece surface without condensate formation. Vapor exposure time is fixed depending on the desired penetration depth. A chamber has heaters, a ventilator for circulating the air/vapor mixture in the chamber to maintain uniform temperature and concentration conditions. A unit separates the process plasticizer vapors from the air/vapor mixture by condensation. A unit filters the residual air/vapor mixture.

As is known, 3D printing processes permit three-dimensional objects to be reproduced from corresponding models made by a 3D modelling software. Machines, apparatuses and entire systems based on such processes are spreading with increased rapidity on the market by virtue also of the reduction of their cost and of an increasingly diversified range of products put on the market covering from professional and/or industrial apparatus up to desktop-type, office and household machines.
The use of 3D printers has rapidly spread from rapid prototyping to a myriad of other applications in a wide variety of areas, from architecture to entertainment, from the biomedical sector to the aerospace sector, and many others.
In general, 3D printing processes involve layer-by-layer deposition of a suitable material to obtain an object in three dimensions. The more widespread technology, mainly by virtue of its low cost, is the deposition printing or FFM/FDM (Fused Filament Fabrication/Fused Deposition Modelling), wherein a polymeric filament is heated up to melting and passed through a nozzle that, under the guide of a software, while moving deposits the material to form overlapping layers. The more commonly used materials in this type of technology are ABS (acrylonitrile-butadiene-styrene) and PLA (polylactic acid). According to other technologies, powder polymeric or metallic materials or liquid polymeric materials are used.
The layer thickness is typically 50-100 micron, but a thickness in the range of 10 micron may be obtained, resulting however in longer manufacturing time. Finishing quality obviously is better by reducing layer thickness, but, nevertheless, the object surface is relatively streaked, uneven and porous, whereby the objects may either display undesired properties (for example, they may become soaked with liquid) or have an appearance unsuitable for their final destination (for example, in the case of decorative objects). In other instances, the surface unevenness does not meet desired requirements and/or dimensional tolerances (for example, where the object manufactured by 3D printing is a mould). In all these cases, and other ones not mentioned related to the quality of the produced piece, surface finishing treatments must be used.
A known method for the surface finishing of plastic material articles obtained, for example, by injection moulding, involves dipping the article in a solvent compatible with the plastic material or exposing the article to vapours of the solvent for a prefixed time sufficient to cause a limited surface solubilisation of plastic material which can flow on the surface on the article surface enough to smooth any roughness present thereon (see for example U.S. Pat. No. 5,448,838).
This method has been extended also to surface finishing of articles made of plastic material obtained by 3D printing. To this subject, see WO03/089218, WO2007/044007, WO2008/088761 and WO2010/002643. 3D pieces, after being produced in a 3D printer, are exposed to vapours of a suitable solvent compatible with the plastic material. Upon contacting the piece, the vapours condense thereon and soften the material to cause the materiel to flow on the surface, thus making the surface smooth. The piece gradually heats until the surface reaches the temperature of the boiling solvent and is constantly covered by solvent condensing on its surface until said temperature is reached. The piece remains exposed to the solvent vapours condensing thereon until the desired finishing degree is obtained and then it is removed from the vapours to allow it to dry through solvent re-evaporation.
Exposition time is decided by observing the solvent vapour condensation on the piece, and the piece may be removed from the vapour chamber when condensation ends, this indicating that the surface temperature of the piece reached the boiling temperature of the solvent. Furthermore the exposition time accounts for the type of solvent and material, the shape characteristics of the piece and the solvent vapour concentration.
This method entails the condensation of the solvent on the surface of the piece as an essential condition. However, a prolonged exposure to the condensed solvent, beside hindering vapour penetration in the surface, may result in erosion and surface runoff with loss of material, and moreover, since the condensate droplets may have preferential flow paths due to the shape of the piece, also the runoff may occur in an uneven manner thus resulting in localized condensate build-up. Furthermore, with the above described known method it is not possible to control the depth of solvent penetration below the surface of the piece.
As a solvent suitable for this application halogenated solvents have been proposed such as trichloroethylene, fluorocarbons and mixtures thereof, ketones such as acetone, methylethylketone, and the like to be selected according to the plastic material and operating conditions.
An apparatus for surface finishing of 3D printing pieces is also disclosed in WO2010002643. The apparatus involves the exposure of an article to solvent vapours to remove surface roughness and porosity and obtain a smooth, glossy surface. The apparatus is formed by a metallic containment box structure having a not-airtight lid, wherein a heated chamber is located. In said chamber the solvent is first vaporized and then the 3D piece to be treated is arranged. The piece is cold or possibly pre-cooled. The containment box structure also houses a drying chamber separated from the heated chamber, in which the 3D piece is transferred at the end of the solvent treatment to remove the solvent therefrom. The drying chamber is maintained to a temperature lower than room temperature to speed up the solvent removal process. Above the heated chamber there is provided a cooling coil to condense the vapours of the solvent which is passed through a water separator before being sent to a solvent collection tank to be re-used.
The apparatus according to the above patent application operates at atmospheric pressure and the heated chamber is kept open during the treatment of the piece to allow the operator to keep the piece suspended in the solvent vapour atmosphere during the whole treatment and to control the result of the treatment. As a solvent a fluorocarbon is used.
The sequence of the operative steps involves first heating of the chamber, wherein liquid solvent has already been charged, to produce solvent vapours, and then dipping the piece in the solvent vapour atmosphere. The solvent vapours are at the operative temperature, whereas the piece is at room temperature at first, whereby necessarily vapour condenses thereon and gradually heats it until an thermal equilibrium condition is reached between the operating temperature and the piece surface temperature. In this condition, the vapour condensation on the piece stops and the treatment ends. Normally the treatment duration (which may be repeated if considered unsatisfactory) is less than few minutes, in some case in the order of 30 seconds.
The above described apparatus is very complex and expensive and uses a highly expensive solvent; therefore it can be of interest for special industrial applications only. Furthermore, since a minimum level of solvent of 0.5 inches has to be maintained at the bottom of the chamber where the solvent is vaporized, the necessary amount of solvent is predictable to be rather high, of the order of some litres. Still, the need of conducting the treatment with the vapour chamber open results in risk of working environment pollution as well as possible risks for operator health holding the piece dipping in the vapour chamber, whereby suitable aspiration systems must be provided. Finally, the transfer of the piece to the drying chamber is an operating complication even in view of the semi-fluid condition of the piece surface at the end of the period of solvent exposure.
Therefore, there is a very felt need for being able to perform surface finishing of pieces mad of plastic material obtained by 3D printing in an effective, quick and safe way and at a cost affordable even for household and office use.

Method and apparatus for surface finishing of articles produced by 3D printing