A liquid crystal display element includes a pair of substrates, a liquid crystal layer sandwiched therebetween, gate lines and drain lines disposed to intersect the gate lines disposed on one of the substrates, thin film transistors disposed at the intersections of the gate and drain lines, pixel electrodes disposed in an area surrounded by two adjacent gate lines and two adjacent drain lines, a common electrode disposed on the other substrate. The liquid crystal display element is also provided with storage lines disposed below the pixel electrodes with an insulating layer interposed therebetween to form a capacitance therebetween. Each of the pixel electrodes is formed with an opening in a portion thereof facing the storage lines.

The present invention relates to a liquid crystal display element, and in particular to a thin film transistor active-matrix type liquid crystal display element provided with a storage capacity formed in a pixel area by a storage line disposed therein and a pixel electrode.
Liquid crystal display devices are widely used as a high-definition color display device for a notebook computer and a display monitor.
Among liquid crystal display elements, the simple matrix type and the active matrix type are well-known. The simple matrix type liquid crystal display element comprises a pair of opposing substrates, a first group of parallel strip electrodes disposed on an inner surface of one of the substrates, a second group of parallel strip electrodes disposed on an inner surface of the other substrate to intersect the first group of parallel strip electrodes, and a liquid crystal layer sandwiched between the substrates. The active matrix type liquid crystal display element comprises a pair of opposing substrates, a plurality of switching elements each provided for selecting a respective pixel and disposed on an inner surface of one of the substrates, and a liquid crystal layer sandwiched between the substrates.
The active matrix type liquid crystal display element is divided into the so-called vertical electric field type which usually called the TN (the Twisted Nematic) type and the so-called horizontal electric field type which is usually called the IPS (the In-Plane-Switching type). In the so-called vertical electric field type as represented by the TN type, two groups of strip electrodes for selection of pixels are disposed on inner surfaces of a pair of upper and lower substrates, respectively. In the so-called horizontal electric field type, two groups of electrodes for selection of pixels are disposed only on an inner surface of one of a pair of upper and lower substrates.
In the TN type active-matrix liquid crystal display element, liquid crystal molecules are oriented to be twisted through 90 degrees, for example, between a pair of opposing substrates. A pair of polarizers are disposed in front of and behind the liquid crystal display element, respectively, such that their absorption axes are at right angles (the arrangement of crossed nicols) with the absorption axis of a polarizer on the entrance side is parallel with or perpendicular to the rubbing direction of the entrance-side substrate.
In the TN type active-matrix liquid crystal display element, first suppose that no electric field is applied across the liquid crystal layer. The incident light is converted into a linearly polarized light by the entrance-side polarizer, the linearly polarized light propagates along the twist of the liquid crystal molecules, and then all of the linearly polarized light passes through the exit-side polarizer and provides a white display if an azimuthal angle of the transmission axis of the exit-side polarizer is identical with that of the linearly polarized light entering the exit-side polarizer. This is the so-called normally open mode.
Next, suppose that an electric field is applied across the liquid crystal layer. The direction (director) of a unit vector representing the average direction of orientations of axes of liquid crystal molecules of the liquid crystal layer is perpendicular to the surface of the substrate, the azumuthal angle of the linearly polarized light entering the liquid crystal layer is not changed, and as a result, it is identical with that of the absorption angle of the exit-end polarizer and consequently, the liquid crystal display element provides a black display. For further detail, see xe2x80x9cBasics and Application of Liquid Crystal,xe2x80x9d Industrial Research Association, Tokyo, 1991.
As described above, the TN type liquid crystal display element includes a pair of opposing transparent insulating substrates made of material such as glass, a liquid crystal layer sandwiched between the opposing glass substrates, a group of scanning signal lines (hereinafter also called gate signal lines) extending in the x direction and arranged in the y direction on the liquid-crystal layer side surface of one of the substrates in a system of rectangular co-ordinates, and a group of drain lines (hereinafter also called video signal lines) insulated from the gate signal lines, extending in the y direction, and arranged in the x direction.
A pixel area is formed in an area surrounded by two adjacent gate lines and two adjacent drain lines, and all the pixel areas form a display area. Formed in each pixel area are a thin film transistor (TFT) serving as an active element (a switching element), for example, and a transparent pixel electrode.
A scanning signal supplied to a gate line switch on a thin film transistor which, in turn, supplies a video signal to a pixel electrode from a drain line.
A capacitance formed by a dielectric of the lighted liquid crystal is not sufficient to maintain the ON (lighted) state of the pixel which has been driven by the thin film transistor during a specified period of time, and therefore an additional capacitance is provided to each pixel so as to replenish the shortage of the capacitance. The additional capacitance has been provided by overlaying a portion of the pixel electrode on the gate line with an insulating layer interposed therebetween.
On the other hand, a storage method is suggested which disposes a storage line in the pixel area and forms a capacitance (a storage capacitance) using a pixel electrode, the storage line and an insulating layer therebetween.
Storage type liquid crystal display devices are disclosed in Japanese Patent Application Laid-open No. Hei 11-231341 (laid-open on Aug. 27, 1999), Japanese Patent Application Laid-open No. 2000-221527 (laid-open on Aug. 11, 2000), and Japanese Utility Model Registration No. 2536632 (registered on Feb. 21, 1997).
FIG. 13 shows an equivalent circuit of a storage type liquid crystal display element. In the storage type liquid crystal display element, a plurality of gate lines GL and a plurality of drain lines DL are disposed to intersect one another in a display area AR on one of a pair of opposing substrates, a thin film transistor TFT is disposed at each of intersections of the gate lines GL and the drain lines DL, and a plurality of storage lines STL are disposed between and parallel with the gate lines GL. Reference character ITO2 denotes a common electrode disposed on an inner surface of the other substrate.
A source electrode (the roles of source and drain may be exchanged in a driving cycle) of the thin film transistor TFT is connected to the pixel electrode ITO1, a liquid crystal capacitance Clc is formed between the pixel electrode ITO1 and the common electrode ITO2 with a liquid crystal therebetween serving as a dielectric, and a storage capacity Cstg is formed between the pixel electrode ITO1 and the storage line STL.
The common electrode ITO2 is supplied with a specified voltage (preferably a fixed voltage) from a common-electrode driving circuit CDR, and the storage lines STL are supplied with a specified voltage (preferably a fixed voltage) from a storage-line driving circuit STR. Reference character GDR denotes a gate line driving circuit, DDR is a drain line driving circuit, CONT is a display control circuit for supplying display signals and timing signals.
FIG. 14 is a plan view of essential parts of a unit pixel and its vicinity formed on a substrate SUB1 of the storage type liquid crystal display element. In FIG. 14, certain of the shapes and dimensions are exaggerated for clarity.
FIG. 15 is a schematic cross-sectional view of the storage type liquid crystal display element taken along line XVxe2x80x94XV of FIG. 14.
In FIG. 14, each pixel is disposed in an area surrounded by two adjacent gate lines GL and two adjacent drain lines intersecting the gate lines GL, and is provided with a thin film transistor TFT at their intersection. The thin film transistor TFT is comprised of the gate line GL, an insulating film (not shown to avoid undue complication of the drawing) covering the gate line GL, a semiconductor layer 100 made of amorphous silicon with the insulating film formed on the insulating film, a pair of a source electrode SD1 and a drain electrode SD2 which are disposed to oppose each other on the semiconductor layer 100. A semiconductor layer integral with the semiconductor layer 100 is disposed below the drain line DL so as to reduce step heights. Reference character SH denotes light-shielding members, reference numeral 102 are openings made in the gate lines GL for the purpose of reducing line defects.
The pixel electrode ITO1 made of transparent conductive film is formed in the pixel area and is connected to the source electrode SD1 of the thin film transistor TFT. The storage line STL is formed in parallel with the gate lines GL, below the pixel electrode ITO1 with an insulating layer interposed (not shown for clarity in FIG. 14, but should be understood to be present) between the pixel electrode ITO1 and the storage line STL in the pixel area. Reference numeral 103 denotes a contact hole made in the insulating layer.
Generally, the storage lines STL are fabricated from the same material as that of the gate lines GL and simultaneously with the gate lines GL. The drain electrode SD2 of the thin film transistor TFT is formed as an extension from the drain line DL.
As shown in FIG. 15, formed on the inner surface of the substrate SUB1 which is also called xe2x80x9cthe thin film transistor substratexe2x80x9d are the storage line STL, a first insulating layer SiN made preferably of silicon nitride, a second insulating layer PAS made of a passivation layer, and the pixel electrode ITO1, in the order named. The common electrode ITO2 is formed on the inner surface of the other substrate SUB2. A liquid crystal layer LC is sandwiched between the two substrates SUB1 and SUB2.
Although not shown in FIGS. 14 and 15, orientation films for orientating liquid crystal molecules are disposed on the respective surfaces of the pixel electrodes ITO1 and the common electrode ITO2, are in direct contact with the liquid crystal layer. In the color liquid crystal display element, three-color filters are disposed below the common electrode ITO2 on the substrate SUB2, and in this case, the substrate SUB2 is also called xe2x80x9ca color filter substrate.xe2x80x9d
In FIG. 15, the storage capacitance Cstg shown as a hatched area is formed by the pixel electrode ITO1, the storage line STL, the first insulating layer SiN and the second insulating layer PAS.
The storage capacitance Cstg is determined by the area of the overlap between the pixel electrode ITO1 and the storage line STL, and is therefore determined by the shape and dimensions of the storage line, and consequently, the exact establishment of the storage capacitance Cstg is difficult, and also the resistance is increased.
The common electrode ITO2 also overlies the gate lines GL and the drain lines DL with the liquid crystal layer interposed therebetween, and therefore a large wiring capacitance is formed between the common electrode ITO2 and the drain and gate lines GL, DL, and consequently delay caused by wiring produces brightness grading in a display image.
FIG. 16 is a schematic cross-sectional view of the liquid crystal display element for explaining a wiring capacitance formed by the gate line GL, and FIG. 17 is a schematic cross-sectional view of the liquid crystal display element for explaining a wiring capacitance formed by the drain line DL. Positioned over the gate line GL are the first insulating layer SiN, the second insulating layer PAS, the liquid crystal layer LC and the common electrode ITO2. Positioned over the drain line DL are the second insulating layer PAS, the liquid crystal layer LC and the common electrode ITO2. Formed between the wiring lines GL, DL and the common electrode ITO2 are wiring capacitances having configurations indicated by broken lines in FIGS. 16 and 17, respectively.
The larger the size of the liquid crystal display element, the longer the lengths of the storage lines STL, the gate lines GL and the drain lines DL, and the larger the wiring capacitances, and therefore the so-called wiring delays occur. Consequently, there is a problem in that flicker or brightness grading occurs in a displayed image.
A voltage supply to the common electrode ITO2 is made via a conductive paste disposed in the vicinity of the sealing member sealing a pair of substrates together along peripheries of a display area of the substrates. The conductive paste is sandwiched between a common-electrode voltage supply line formed on the substrate SUB1 and the common electrode ITO2 formed on the other substrate SUB2.
FIG. 18 is a schematic plan view of the liquid crystal display element for explaining an example of positions of the conductive pastes for electrically connecting the common-electrode voltage supply line on the substrate SUB1 to the common electrode ITO2 on the substrate SUB2.
In this liquid crystal display element, the substrates SUB1 and SUB2 are sealed together by placing the substrate SUB2 over the substrate SUB1 with a sealing member SL interposed therebetween along the periphery of the display area AR of the substrates SUB1 and SUB2.
The common-electrode voltage supply line (not shown) is formed in the vicinity of the sealing member SL on the substrate SUB1. In the sealing operation, the conductive paste CPT is coated to overlie the common-electrode voltage supply line at positions such as corners of the sealing member SL coated on the substrate SUB1, and then the substrate SUB2 is placed over the substrate SUB2 such that the common electrode ITO2 on the inner surface of the substrate SUB2 is electrically connected to the conductive paste CPT to make possible application of a specified voltage to the common electrode ITO2.
A voltage supply to the storage lines STL is made by connecting a storage-line voltage supply line (not shown) formed in the vicinity of the sealing member SL on the inner surface of the substrate SUB1 to a power supply (a storage-line driving circuit) at one side or both sides of the display area.
However, there is a problem in that, the longer the storage lines, the larger the resistance and a wiring capacitance, and fluctuations in potentials occur, and consequently, flicker and brightness grading occur in a display and they deteriorate the quality of the display.
As for a measure against these, the number of the coated conductive pastes can be increased, the coating operation of the conductive pastes requires a lot of time, and as a result, the so-called tact time is increased. In a driving method employing the common-electrode voltage inversion, it is difficult to reduce the number of the points for voltage supply because a signal is supplied to the common electrode.
It is an object of the present invention to provide a liquid crystal display element capable of suppressing occurrence of flicker and brightness grading in a display by solving the problems with the prior art, facilitating the establishment of a desired storage capacitance, and reducing a storage capacitance, wiring capacitances formed by gate lines or drain lines, and further capable of improving a manufacturing tact.
To achieve the above object, the present invention is capable of establishing the storage capacitance value in accordance with the storage line by providing an opening in a pixel electrode, reducing wiring capacitances of gate lines and/or drain lines by providing cutouts in a portion of a common electrode overlying (or being located at an opposite side of the liquid crystal layer to) the gate lines and/or the drain lines (e.g. by eliminating the portion of the common electrode so as to form an opening therein), or supplying a voltage to the common electrode or the storage lines by providing column-like conductive spacers between the common electrode and the storage lines without a conductive paste.
The following describes representative configurations of the liquid crystal display elements in accordance with the present invention.
In accordance with an embodiment of the present invention, there is provide a liquid crystal display element comprising: a pair of substrates; a liquid crystal layer sandwiched (or interposed) between the pair of substrates; a plurality of gate lines disposed on one of the pair of substrates; a plurality of drain lines disposed to be insulated from and intersect the plurality of the gate lines on the one of the pair of substrates; a plurality of thin film transistors disposed in a vicinity of intersections of the plurality of gate lines and the plurality of drain lines; a plurality of pixel electrodes made of transparent conductive material, each of the plurality of pixel electrodes being disposed in an area surrounded by two adjacent ones of the plurality of gate lines and two adjacent ones of the plurality of drain lines, and driven by a corresponding one of the plurality of thin film transistors; a common electrode disposed on another of the pair of substrates to face the plurality of pixel electrodes; and a plurality of storage lines disposed below the plurality of pixel electrodes with an insulating layer interposed between the plurality of storage lines and the plurality of pixel electrodes, each of the plurality of pixel electrodes being formed with an opening in a portion thereof facing a corresponding one of the plurality of storage lines.
In accordance with another embodiment of the present invention, there is provided a liquid crystal display element comprising: a pair of substrates; a liquid crystal layer sandwiched (or interposed) between the pair of substrates; a plurality of gate lines disposed on one of the pair of substrates; a plurality of drain lines disposed to be insulated from and intersect the plurality of the gate lines on the one of the pair of substrates; a plurality of thin film transistors disposed in a vicinity of intersections of the plurality of gate lines and the plurality of drain lines; a plurality of pixel electrodes made of transparent conductive material, each of the plurality of pixel electrodes being disposed in an area surrounded by two adjacent ones of the plurality of gate lines and two adjacent ones of the plurality of drain lines, and driven by a corresponding one of the plurality of thin film transistors; and a common electrode disposed on another of the pair of substrates to face the plurality of pixel electrodes, the common electrode being formed with cutouts in portions thereof facing at least one of (1) the plurality of gate lines and (2) the plurality of drain lines.
In accordance with another embodiment of the present invention, there is a liquid crystal display element comprising: a pair of substrates; a liquid crystal layer sandwiched (or interposed) between the of substrates; a plurality of gate lines disposed on one of the pair of substrates; a plurality of drain lines disposed to be insulated from and intersect the plurality of the gate lines on the one of the pair of substrates; a plurality of thin film transistors disposed in a vicinity of intersections of the plurality of gate lines and the plurality of drain lines; a plurality of pixel electrodes made of transparent conductive material, each of the plurality of pixel electrodes being disposed in an area surrounded by two adjacent ones of the plurality of gate lines and two adjacent ones of the plurality of drain lines, and driven by a corresponding one of the plurality of thin film transistors; a common electrode disposed on another of the pair of substrates to face the plurality of pixel electrodes; a plurality of storage lines disposed below the plurality of pixel electrodes with an insulating layer interposed between the plurality of storage lines and the plurality of pixel electrodes, each of the plurality of pixel electrodes and a portion of the insulating layer thereunder and being formed with an opening in a portion thereof facing a corresponding one of the plurality of storage lines, the opening passing through all thicknesses of the plurality of pixel electrodes and the insulating layer; a plurality of column-like conductive spacers, each of the plurality of column-like conductive spacers disposed in a respective one of the openings for electrically connecting one of the plurality of storage lines to the common electrode.
In accordance with another embodiment of the present invention, there is provided a liquid crystal display element comprising: a pair of substrates sealed together along peripheries thereof with a sealing member; a liquid crystal layer sandwiched (or interposed) between the pair of substrates; a plurality of gate lines disposed on one of the pair of substrates; a plurality of drain lines disposed to be insulated from and intersect the plurality of the gate lines on the one of the pair of substrates; a plurality of thin film transistors disposed in a vicinity of intersections of the plurality of gate lines and the plurality of drain lines; a plurality of pixel electrodes made of transparent conductive material, each of the plurality of pixel electrodes being disposed in an area surrounded by two adjacent ones of the plurality of gate lines and two adjacent ones of the plurality of drain lines, and driven by a corresponding one of the plurality of thin film transistors; a common electrode disposed on another of the pair of substrates to face the plurality of pixel electrodes; a lead disposed on the one of the pair of substrates for supplying a voltage to the common electrode; a plurality of storage lines disposed below the plurality of pixel electrodes with an insulating layer interposed between the plurality of storage lines and the plurality of pixel electrodes, each of the plurality of pixel electrodes and a portion of the insulating layer thereunder and being formed with an opening in a portion thereof facing a corresponding one of the plurality of storage lines, the opening passing through all thicknesses of the plurality of pixel electrodes and the insulating layer; a plurality of column-like conductive spacers, each of the plurality of column-like conductive spacers disposed in a respective one of the openings for electrically connecting one of the plurality of storage lines to the common electrode; and a column-like conductive spacer disposed in a vicinity of the sealing member for electrically connecting the common electrode to the lead.
In one of concrete structures of the aforementioned liquid crystal display devices according to the present invention, the plurality of storage lines are arranged to form a capacitance together with one of the plurality of pixel electrodes corresponding thereto and the insulating layer interposed between the one of the pixel electrodes and the one of storage lines, respectively. The vicinity of intersections of the plurality of gate lines and the plurality of drain lines defines an area not only close to the intersection but also any area where one of the plurality of thin film transistor can connect a gate electrode thereof electrically to one of the plurality of gate lines and a drain electrode thereof electrically to one of the plurality of drain lines, respectively. Each one of the plurality thin film transistor has a field effect type transistor structure which switches a current between a source electrode thereof and a drain electrode thereof in accordance with an electrical field applied by a gate electrode thereof, for example. While definitions of the source electrode and the drain electrode in the thin film transistor are reversed in accordance with a current direction therebetween, one of the source and drain electrodes being connected to one of the plurality of the drain lines will be defined as a drain electrode, and another of the source and drain electrodes being connected to one of the plurality of the pixel electrode will be defined as a source electrode, in this specification for convenience. In the other one of concrete structures of the aforementioned liquid crystal display devices according to the present invention, a conductive layer may be interposed between one of the plurality of storage lines and one of the column-like spacers to cover the one of the plurality of storage lines. In this structure, the conductive layer should be made of same material as that of the plurality of pixel electrodes, or of such an oxide material having electrical conductivity as an Indium-Tin-Oxide or an Indium-Zinc-Oxide.
The present invention. is not limited to the above configurations and the embodiments described subsequently, but various changes and modifications may be made without departing from the nature and spirit of the invention.

Liquid crystal display having an opening in each pixel electrode corresponding to each storage line


A method and apparatus of detecting user initiated movement by an input element handled by a user is disclosed. The method may include performing a calibration procedure that is initiated by the user via a physical movement performed by the user. The method may also include positioning at least one sensor to dynamically adjust a size of an effective workspace range capable of detecting the user's movement of the input element.

Before typewriters and computers, individuals typically wrote using handheld writing implements, such as pens or pencils. In addition, even given the benefits of a keyboard and computer mouse, there are situations in which a user of an electronic device, such as, a personal computer, could benefit from using a pen-shaped writing implement to create information. In one example, a computer graphic artist may desire to draw something directly on the display screen of a computer. Certainly, the artist may rely on the mouse as an input device to the computer, however, while the mouse may provide the customized input, the mouse may not provide a sensitive and/or comfortable enough option for the artist who is accustomed to using a handheld pen to draw a picture.
One conventional product used to draw with a computer is the Wacom® pen tablet device. Specifically, the Wacom® Intuos® line of pen tablet devices provides a device that may accept pen movement by hand and relay that input to the computer display. These tablet products consist of a tablet and a pen-shaped stylus (i.e., pen shaped handheld device).
FIG. 1 illustrates an example of a conventional tablet device and a stylus 10 that may be handled by a user. Another example tablet may incorporate the use of a mouse (not shown). When the user moves the stylus pen on the tablet, the onscreen pointer moves in the same manner as a mouse. In effect, the mouse and mouse pad are replaced with the pen and the tablet.
The tablet, unlike the mouse pad, is not restricted to a horizontal plane since the stylus remains in the user's hand and is therefore still operable when the stylus is shifted outside of the tablet's plane. To the contrary, the mouse rests on the mouse pad and is subject to sliding off the pad. In addition to strictly 2-dimensional inputs from the user of a mouse (i.e., up/down and left/right), tablets are pressure sensitive so that the computer is provided with an additional input describing how hard the user is pressing the stylus into the tablet.
FIG. 2 illustrates a simplified drawing of the electronic components of a pen tablet device. Referring to FIG. 2, a stylus pen 20 and a tablet 30 are illustrated as having an amplifier component 41 and an A/C power source 42 as some basic components of the tablet's circuitry.
Due to the tablet's widespread success and acceptance, many popular software applications have been created with a user interface designed to accommodate a pen tablet as an input device. These software applications receive and process the same position inputs that would otherwise be generated from a computer mouse. For those signals associated with a pen tablet input, additional pressure sensors may also be used adding an additional input feature. For example, a graphics program such as Adobe Photoshop® could be used to create a thicker line onscreen when the user increases the downward pressure on the stylus. In addition, the tilt of the stylus may also be detected and used as an additional mode of input. The stylus can even be turned around so that the "eraser" end is used as yet another input type or input eraser.
While the pen tablet devices remain popular, they are not the only technology in existence that may be used to generate user handheld information. For instance, touch-screen devices are also types of hand initiated input devices. For example, Elo Touchdevices® are one brand of touch-screen monitors. Touch-screens generally are similar to pen tablets with a couple of differences. For example, with touch-screens, the stylus is always a passive device, and thus it could be a pen, a finger, or even the corner of a credit card that is used to touch the pad and generate an input. In addition, the tablet portion of touch-screen devices is built into the display itself. Therefore, a typical touch-screen device might be controlled by a user tapping and/or dragging a finger on the device's display, while a pen tablet device would combine a traditional display with a separate stylus and tablet.
FIG. 3 illustrates a touch-screen device in use. The monitor 31 provides a touch-screen that may be accessed by a user finger 50. The technology involved in detecting the position of a stylus (whether active or passive) on a screen (whether a tablet or a display) may be similar for both examples. For example, pen tablet devices in which the stylus is passive is similar to a touch-screen which is always passive. When referring to these example devices, the term "pen tablet device" will be used with the understanding that the touch-screen device may also be considered a particular type of a pen tablet device.
Generally, pen tablet devices include two components, which include the pen or stylus and the tablet. Some pen tablet devices utilize an "active" stylus, meaning that the stylus needs to be provided with a power supply in order to operate. Other types utilize a passive stylus whose position is detected by the active element in the tablet surface. These design factors influence the ultimate design of the devices since passive components can be made smaller and lighter, as well as wirelessly.
Although these above-noted technologies may be different, the technology employed for the detection process is not of great importance to the typical user. Rather, the manner in which the user interacts with the product is of greater importance to the user. In other words, most users don't have a preference whether a given device uses a touch-sensitive writing surface to detect position, or, if it instead uses passive or actively-generated magnetic fields to operate. The user is more concerned about features, such as, wired versus wireless operation, device weight, device precision and sensitivity, durability, and size.
Within the user's interaction, some features may be more important to the user. Obviously, a wireless tablet would have certain advantages over a wired tablet, however, perhaps a wireless stylus would be of less significance since the stylus is never far from the tablet.
With any pen tablet device, there is a concern that some amount of drift will occur. Generally, the accuracy of an electronic stylus data input device may only be as accurate as the amount of drift that occurs. One procedure to minimize the amount of drift that occurs is to perform a proper calibration procedure.
Certain tablet technologies rely on natural magnetic fields, which can be affected by various forms of interference, such as, metallic objects. If a pen tablet device is operating based on the predefined characteristic that the magnetic field environment is static, and the user is moving unexpectedly or a metallic object is brought near the surface of the tablet, then certain drift may be experienced compromising the user's writing experience (e.g., a truck drives towards the vicinity of the tablet device). Certainly, such a distraction will influence the magnetic field near the device and cause distortion.
These type of inertial devices measure their own movements using inertial sensors (e.g. gyroscopes and accelerometers) which provide readings as to how the devices have moved since they initially began receiving data measurements. These devices do not use a calibration procedure prior to allowing user input. As a result, small errors build up over time because the true position of the device and user's movements is not known.
For the magnetic case, the error could be from a shifting reference point due to the shifting magnetic field, while in the inertial case, the error may simply compound because the measurements are made with respect to the previously calculated position.
The user interaction is a factor to consider in the design of the pen tablet device. Nevertheless, there are numerous other features which may be exploited, such as, initial setup procedures, to expand the options, quality and overall performance available to the user.

This patent is subject to a terminal disclaimer.

Method and apparatus of position tracking and detection of user input information


A core remover for removing cores from paper rolls comprising a two-piece heating conducting tube, the top part of the tube having, a smooth tapered tip, containing a thermostat bulb and a heating element for heating the tube, and the connection elements for the thermostat and heating element extending downward through the bottom part of the tube and to the thermostat. The thermostat and heating element are connected so that control of the temperature of the heating element and tube may be made. A core with paper wrapped around it is placed over the tube and heated for a few seconds to loosen the glue. Following that, the core is manually removed and at the same time or after, the inner most sheet of paper is pulled about 2 inches from the center of the paper roll.

The device of this invention is a core remover for removing the core from paper toweling and the like. It is becoming popular to sell paper toweling and toilet tissue in rolls from which the cardboard core has been removed so that the toweling or tissue can be withdrawn from the center of the roll rather than unwound from the outside. In order to do that it is necessary to remove the cardboard paper core from the toweling center. The normal roll of paper towel is made by gluing the original strip of paper to the cardboard core and rotating the core so as to wind the paper into a roll.
Since the paper is glued to the paper core and is tightly wound into a roll it is difficult to remove the core after the roll has been formed. The inventor has found by means of a unique and simple design that removal of the paper core may be quickly and efficiently effected. The inventor knows of no prior art which either teaches or shows the present invention.
For example, U.S. Pat. No. 5,100,075 (Morand) discloses a core remover but that structure is not heated. The Morand core remover also serves as a spindle on which the roll is mounted. There is no discussion of central dispensing.
U.S. Pat. Nos. 3,965,808 (Chomette) and 3,635,146 (Aubert) both deal with heating bread. Their only similarity to the present invention is the physical form of the heater similar to the core removal apparatus of the present invention. However, while the physical form of the device is similar they differ substantially from the present invention as claimed.
U.S. Pat. No. 4,763,785 (Bradley et al.) discusses a very different method of core removal involving a core which is wrapped in paper treated with a release agent. The object of this device is center dispensing. However, the structure of the present invention is not disclosed.
U.S. Pat. No. 4,919,759 (Ilmarinen et al.) discloses the use of heat but the invention of that particular patent discloses the heat being applied to a machinery roll rather than to a core on which paper is wound. The purpose of the structure is quite different, having to do with the behavior of paper in a printing press.
U.S. Pat. No. 4,889,598 (Niskanen) is similar to U.S. Pat. No. 4,919,759. U.S. Pat. No. 3,473,005 (Grandinette) is even less pertinent since it has to do with the heating of a hair roller.


A load bearing structure having a set of uniform voids functions to resolve the forces imposed by developing compression in the material having the voids and minimizing the amount of tension developed in the material. For the voids to have this function, they must be deployed in a particular fashion. The voids are deployed to encompass a particular set of points. The set of points are such that each point in the matrix is spaced an equal distance from twelve and only twelve adjacent points of the matrix. The distance between the points does not matter as long as all are uniformly distanced in accordance with that rule. If the structure is considered to be composed of a closely packed set of hypothetical rhombic dodecahedra (RD) and the four edge vertices of each of those hypothetical RDs is truncated, the result will be a set of cubic voids. The center of each of those cubic voids will define the matrix referred to above and the cubic voids will serve to provide the optimum resolution of stress which minimizes the development of tension in the material. One in four of the hypothetical or mathematical RDs can be eliminated achieving the same force resolution result in a structure that contains less material. The shape and size, but not the position, of the voids can be varied with only slight loss in optimum stress resolution. Some voids can be omitted with only slight loss of optimum stress resolution.

This invention relates in general to structures such as load bearing structures and more particularly to structures that provide an enhanced trade-off between the stress that can be safely carried in relation to the amount of material required for the structure.
This enhanced strength to weight ratio is the goal of a large number of designs including many of those proposed and constructed by Richard Buckminster Fuller.
In most contexts where load bearing structures are employed and especially in bridges and beams, in arches and trusses, failure occurs because of a failure in tension rather than in compression. Although the loads imposed primarily induce compressive stress in the material, that stress is resolved within the material by vectors which introduce tension. For example, a bridge subject to load on its upper surface will tend to deflect in such a fashion as to introduce a tension along its lower surface. Failure will occur because of a failure in tension.
To compensate for this effect, rods or fibers which are particularly strong in tension can be incorporated. Multiple ply and laminated materials having varied fiber orientation in different layers are frequently employed to resist tension. In some materials and in particular with ceramics, careful attention is paid to minimize grain boundaries where failure tends to appear.
Attention has been paid to developing materials which have great tensile strength for use in load bearing structures in such a way as to employ the tensile strength of these materials so that loads applied to the structure will be resolved, at least in part, by the tension created in these tension members. Such an approach is outlined in the Buckminster Fuller U.S. Pat. No. 3,354,591 issued in 1967. A more recent improvement on that structure is set forth in U.S. Pat. No. 4,207,715 issued in 1980. This combination of tension and compression members is also disclosed in the structure shown in U.S. Pat. No. 4,711,062 issued in 1987.
As a general rule, most cost effective materials of load bearing structures are far stronger in compression than in tension. This is true of concrete, steel and aluminum, for example. The design of structures using such materials is widespread because of availability and reasonable cost.
Accordingly, it is a major object of this invention to provide a structure which has an improved stress resolution performance using a material having greater compression strength than tensile strength.
It is a related purpose of this invention to provide an improved load bearing structure whose critical failure point will be a function of its strength in compression, rather than its strength in tension.
It is a further related purpose of this invention to provide a load bearing structure which for a predetermined failure point will require less material than is currently required by known structures.


A method for manufacturing an ink jet recording head, which is provided with a plurality of ink paths structured by bonding a second substrate having a plurality of grooves arranged thereon to form ink paths corresponding to a plurality of discharge openings, together with a first substrate having discharge energy generating devices arranged in the ink paths, respectively, comprises the step of processing the grooves constituting the ink paths on the second substrate by means of formation processing, and laser processing, divisionally. This method makes it possible to process ink flow paths with ease and good production yield even when the ink flow paths are arranged in such a high density that its formation becomes difficult by the application of formation processing, and also, to reduce the total energy of laser when ink flow paths are processed as compared with the method adopted conventionally. The required load given to the optical system of a laser processor is made smaller accordingly.

1. Field of the Invention
The present invention relates to a method for manufacturing an ink jet recording head, and an ink jet recording head manufactured using such method of manufacture.
2. Related Background Art
Conventionally, as disclosed in the specification of Japanese Patent Laid-Open Application No. 55-132253, for example, an ink jet recording head is structured by bonding a first substrate, which is provided with discharge energy generating devices arranged on a silicon substrate, together with a second substrate, which is provided with the recessed portion that forms ink flow paths when bonded to the first substrate; an orifice plate conductively connected with the ink flow paths to form discharge openings for discharging ink; and the recessed portion that constitutes a common liquid chamber that provisionally retains ink to be supplied to each of the discharge openings.
Also, in the specification of Japanese Patent Laid-Open Application No. 2-121845, a method for processing the grooves that constitute ink paths is introduced for an ink jet recording head structured by bonding a ceiling plate, which is provided with the recessed portions to form ink paths arranged corresponding to each of a plurality of discharge openings, as well as a common liquid chamber that retains ink to be supplied to the ink paths, together with a substrate having discharge energy generating devices arrange on a part of each of the ink paths. In this method, the ceiling plate having the grooves to form the common liquid chamber is produced by means of an injection molding, and then, the ink paths are formed by the irradiation of excimer laser on the ceiling plate thus produced.
However, in recent years, there have been more demands on higher precision as image quality along with the wider use of digital cameras or the like. In order to meet such demand on the image quality that requires higher precision, the density of ink flow paths should be arranged to be as high as 600 DPI (the pitches of ink flow paths being 42.375 .mu.m) or more. However, in accordance with the method for forming the ink flow paths by means of injection molding, which is disclosed in the Japanese Patent Laid-Open Application No. 55-132253, the production yield should be extremely lowered if this method is adopted for manufacturing heads having such higher density of flow paths as compared with the heads conventionally in use. Here, the problems are encountered, such as defective flow-in of resin into the metallic mold, and the chips that may be present at the time of mold releasing to make the product defective. Also, regarding the method for forming ink flow paths by the irradiation of excimer laser, which is disclosed in the Japanese Patent Laid-Open Application No. 2-121845, the region of laser irradiation should be increased in order to meet the demand on the higher density of ink flow path arrangement. This requirement results in the heat accumulation on the ceiling plate more than conventionally accumulated on it, which inevitably leads to the expansion of the work. At the same time, with the higher arrangement of ink flow paths thus required, allowable errors become smaller so that it is made difficult to stabilize the formation of ink flow paths in a desired precision.
As described above, therefore, there is a need for the provision of a method for manufacturing ink jet recording head, which is capable of forming the ink flow paths in a desired precision stably when the ink flow paths should be arranged in a density of as high as 600 DPI or more, for example.

Method for manufacturing an ink jet recording head and an ink jet recording head


A fire proof cable tray constructed of assemblable units, each of which comprises a metal frame having a wire mesh covering attached thereto, an intumescent coating encapsulating the wire mesh, a layer of an inorganic, non-combustible fiber mat and a sheet of metal foil. The foil, fiber mat and encapsulated screen are mechanically secured together. The units can be assembled on the job site to form a cable tray for protecting control lines in a refinery or chemical plant.

(1) Field of the Invention
The invention is directed to a fire proof cable tray for carrying operating control tubes and instrumentation lines in refineries and chemical plants.
(2) Prior Art
There has long been a need for fire proofing operating control cables and instrumentation lines in oil refineries and chemical plants. Often in gasoline, fuel oil, and similar types of fires the temperature in the fire environment exceeded 2200.degree. F., with heat flux levels up to 26 Btu per square foot second. Because of the high flammability of products being stored and transported, protection against high temperature petroleum flash fires for extended periods of time is essential.
It is necessary that control cables and instrumentation lines must be made to withstand high temperatures, in the fires, for periods of time from 15 to 20minutes, or more, to permit an orderly shutdown to isolate the system and the fire extinguished with a minimum of damage to the control system.
Use of fire retardant coating systems for the control cables and instrumentation lines does not provide for adequate protection in hot fires, or for extended burning times. These cables and electrical lines are usually distributed throughout the plant and are generally all conducted through "trays", called cable trays, rather than through metal conduits. The cables and lines are simply laid out in these trays throughout the plant.
The advantage of the cable tray system is that repair work and adding new lines is often simplified, due to the easy access to the tray and its contents. A disadvantage is that, in the tray, the fire hazard is increased because of the number of cables set side by side, as well as the combustible debris which may collect in the suspended trays.
Other investigators have attempted to provide cable tray systems which provide fire protection for extended periods of time, i.e., in excess of 15 minutes. Most have concentrated on systems which merely stack layers of non-burning, insulating material either inside or outside the cable tray. For example, U.S. Pat. No. 4,064,359 discloses use of a two-layer blanket of fibers. The inner layer consists of glass fibers. The layer is coated with a halogen-containing coating containing 3 to 75% fire-proof fibers, such as asbestos.
U.S. Pat. No. 4,054,711 teaches a jacketing material having a polyester film, aluminum coating, asbestos paper, glass cloth and an outer layer of polyvinyl fluoride film. The fire-proof wrap material is used in a manner similar to the '359 patent. A cable coating which may be sprayed on is taught in U.S. Pat. No. 3,928,210. The slurry for spraying consists of non-combustible fibers in a water based resinous emulsion. U.S. Pat. No. 4,058,643 teaches use of an intumescent adhesive layer in fire retardant laminates. The inventor uses an intumescent adhesive to secure a polyethylene film to insulation batting. Two other patents of interest are U.S. Pat. No. 4,069,075 and U.S. Pat. No. 4,112,179.
It is an object of the invention to provide a cable tray construction to provide a fire protective insulating product capable of protecting control cables and instrumentation lines, contained therein, from external fire temperatures of at least 2200.degree. F. for a period of time in excess of 15 minutes.
It is a further object to provide an easily assembled, prefabricated cable tray capable of protecting the cables and lines secured therein from fire temperatures of 2200.degree. F. and higher for a period of time in excess of 15 minutes.
Another object is to provide the above cable tray which is adaptable for encasing cables and lines and also encasing structural beams in a refinery or plant.


A system for attenuating seismic forces includes a reactor pressure vessel containing nuclear fuel and a containment vessel that houses the reactor pressure vessel. Both the reactor pressure vessel and the containment vessel include a bottom head. Additionally, the system includes a base support to contact a support surface on which the containment vessel is positioned in a substantially vertical orientation. An attenuation device is located between the bottom head of the reactor pressure vessel and the bottom head of the containment vessel. Seismic forces that travel from the base support to the reactor pressure vessel via the containment vessel are attenuated by the attenuation device in a direction that is substantially lateral to the vertical orientation of the containment vessel.

Seismic isolation may be utilized to control or reduce the response of a component or structure to vertical and horizontal ground-input motions or accelerations. Seismic isolation may accomplish this by decoupling the motion of the component/structure from the driving motion of the substructure. In some instances, hardware (e.g., springs) may be positioned between the substructure and superstructure. Use of such hardware may minimize the dynamic response of the structure by increasing the fundamental period of vibration for the component or structure, resulting in lower in-structure accelerations and forces. To further reduce spectral response amplitudes (e.g., deflections, forces, etc.), other mechanisms may be employed that effectively reduce the peak amplitude to manageable levels.
Piping and other connections may be provided between a nuclear reactor and a secondary cooling system or other systems in the power generation facility. In the event of an earthquake or other seismic activity, significant forces or vibration may be transferred to, or by, the connections, which can place great stress on the connections. Forces resulting from thermal expansion also place stress on the connections. Maintaining integrity of these connections helps discourage the inadvertent release of radioactive or other materials from the various systems, and reduces maintenance or damage that might otherwise occur if one or more of the connections fail.
During a seismic event, dynamic and/or seismic forces may be transmitted from the ground, support surface, or surrounding containment building to a reactor module. The seismic forces which are transferred to the reactor module may experience a cumulative increase and/or amplification in amplitude and/or frequency depending on the number and/or length of intervening structures and/or systems that the seismic forces travel in reaching the reactor module. If the seismic forces become large enough, the reactor core and/or fuel elements may be damaged.
The present invention addresses these and other problems.

Seismic attenuation system for a nuclear reactor


A portable radio telephone comprises a receiver section including at least an RF amplifier and a first frequency mixer. The telephone also comprises a battery which supplies a first voltage to the receiver section when the telephone is in portable use. When the telephone is mounted on a vehicle, a vehicle battery applies a second voltage which is higher than the first voltage, to the RF amplifier and to the frequency mixer. By this higher voltage supply, the intermodulation characteristic and reception sensitivity of the receiver section can be improved in the vehicle-mounted use. On the other hand, battery saving can be achieved by the lower voltage supply in the portable use.

The present invention relates to a radio apparatus and, more particularly, to a radio telephone to be used as a portable or a vehicle-mounted telephone.
A conventional radio telephone is energized by a battery in portable use and by a vehicle battery in vehicle-mounted use. In both cases, a DC voltage is applied to a receiver section through a voltage stabilizer. The voltage to be applied to the receiver section is minimized to save the battery power in the portable use. As a result, in the vehicle-mounted use, receiver performance such as an intermodulation (IM) characteristic and reception sensitivity is sacrificed for the power saving. On the contrary, if the voltage is increased to improve the receiver performance, the life of the battery for portable use will be shortened.

Radio telephone suitable for portable and vehicle-mounted use


An exemplary electronic light processing cell uses a photo sensor unit to provide an analog electrical output proportional to an amount of light impinging on the photo sensor. A noise source provides a noise output that is compared by a comparator, during a plurality of times during a frame of an image, with the analog electrical output to generate a binary digital output representative of each comparison. A digital counter counts the binary digital outputs during the frame and stores a count at the end of a frame where the value of the stored count is proportional the light impinging the photo sensor. The value of the stored count is adapted for use by an image processing unit to render an image.

This invention relates to the recovery of output or event detection from individual pixel sites and more specifically relates to a technique that digitizes analog voltage from the unit cell. In one embodiment a capacitor at the unit cell is not required.
A common technique to digitize an analog current output from each photo detector in an array uses a capacitor to integrate the current output into a proportional voltage level which is then converted into digital signal by an analog to digital converter. As pitches, i.e. the distance between adjacent photo detectors, in large arrays gets smaller to achieve increasing finer image resolution, the smaller resulting area available for the capacitors may lead to the use of capacitors with smaller capacitance values. This may degrade the dynamic range and performance of the processing of the photo detector output. Thus, there exists a need to be able to accommodate increasingly dense photo detector arrays and the associated area restrictions per cell site.

Pixel information recovery by oversampling a comparison of pixel data and a noise signal


A method of manufacturing a multi-layer circuit board including preparing a laminated member formed of (i) a core circuit board having a circuit pattern thereon and (ii) a prepreg sheet having a through-hole filled with conductive paste, forming a laminated structure such that the laminated member is sandwiched by lamination plates, and applying heat and pressure to the laminated structure. According to this method, selecting a lamination plate that has a thermal expansion coefficient that is equivalent to that of a core circuit board will protect the conductive paste from distortion, thereby offering a high-quality multi-layer circuit board having a reliable connection resistance.

1. Field of the Invention
The present invention relates to a method of manufacturing a multi-layer circuit board that has inner via-hole connection via conductive paste.
2. Description of the Related Art
In recent years, as electronic devices are formed into smaller in size and higher in-density, a multi-layer circuit board has been strongly needed not only for industrial use but also for consumer products.
To provide a multi-layer circuit board with high-density, microscopic and multi-layered circuit patterns have been developing. At the same time, a thin circuit board has also been needed.
Such a multi-layer circuit board requires highly reliable interlayer connections in which circuit patterns formed on the layers are connected via inner via-holes. For example, Japanese Patent Unexamined Publication No. H06-268345 introduces a method of manufacturing a high-density circuit board that offers inner via-hole connections via conductive paste filled in via-holes.
Hereinafter will be described a conventional method of manufacturing a multi-layer circuit board, in particular, a four-layered circuit board.
First, a description will be given on the manufacturing process of a double-sided circuit board that is the base of a four-layered circuit board.
FIGS. 5A through 5F illustrate the manufacturing process of a conventional double-sided circuit board, showing step-by-step sectional views until the circuit board is done.
Prepreg sheet 21 is 250 mm×250 mm square and approx. 150 μm in thickness. Prepreg sheet 21 is formed of composite material, for example, a non-woven fabric made of aromatic polyamide fiber impregnated with thermosetting epoxy resin. Mold releasing film 22, which is made of polyethylene terephthalate or the like, has a thickness of approx. 10 μm. On one surface of film 22, a silicone mold releasing agent is applied. Metal foil sheets 25a and 25b, made of Cu or the like, 12 μm-in thickness, cover each surface of prepreg sheet 21. Through-holes 23 in prepreg sheet 21 are filled with conductive paste 24, through which foil sheet 25a establishes electrical connection to foil sheet 25b.
As shown in FIGS. 5A and 5B, through-holes 23 are formed at predetermined positions, by laser processing or the like, in prepreg sheet 21 having mold releasing film 22 on both surfaces.
Through-holes 23 are, as shown in FIG. 5C, filled with conductive paste 24. Specifically, prepreg sheet 21 with through-holes 23 is put on a printer table (not shown), and then conductive paste 24 is directly printed on mold releasing film 22. In the printing process, mold releasing film 22, particularly the upper one, not only serves as a printing mask but also keeps the surface of prepreg sheet 21 clean.
After that, mold releasing film 22 is removed from both surfaces of prepreg sheet 21, as shown in FIG. 5D.
FIG. 5E shows a laminated state in which lamination plate 26b, metal foil 25b, prepreg sheet 21, metal foil 25a, and lamination plate 26a are stacked up in the order. The laminated structure undergoes heat pressing. The application of heat and pressure not only compresses down prepreg sheet 21 as shown in FIG. 5F (where, t2 measures approx. 100 μm), but also attaches metal foil sheets 25a, 25b with prepreg sheet 21. In this way, metal foil sheets 25a and 25b have electrical connections via conductive paste 24 filled in through-holes 23 formed at predetermined positions in the prepreg sheet. Following the above-described steps, a circuit pattern is formed (not shown) by selective etching on metal foil sheets 25a and 25b. The double-sided circuit board of FIG. 5F is thus obtained.
Next, a conventional method of manufacturing a multi-layer circuit board is described. Taking a four-layer circuit board as an example, the sectional views in FIGS. 6A through 6D illustrate a method of manufacturing a multi-layer circuit board.
First, as shown in FIG. 6A, double-sided circuit board 30 as a core circuit board, and prepreg sheets 21a, 21b are prepared. Circuit board 30 having circuit patterns 31a and 31b thereon is formed through the processes from FIG. 5A to FIG. 5F. Prepreg sheets 21a and 21b have through-holes filled with conductive paste 24.
The aforementioned materials are stacked up, as shown in FIG. 6B, together with following components in the order: lamination plate 26b, metal foil 25b made of copper or the like, prepreg sheet 21b, double-sided circuit board 30, prepreg sheet 21a, metal foil 25a, lamination plate 26a. The laminated structure is held by buffer material (not shown) and positioned on a heat press plate (not shown) to undergo heat pressing. With the application of heat and pressure, prepreg sheets 21a and 21b are compressed down (t2 measures approx. 100 μm), metal foil sheets 25a and 25b are bonded with double-sided circuit board 30, and circuit patterns 31a and 31b establish inner-via-hole connections to metal foil sheets 25a and 25b via conductive paste 24.
In the heat pressing process, to protect metal foil sheets 25a and 25b from formation of wrinkles, lamination plates 26a and 26b are usually formed of material having a coefficient of linear expansion equivalent to that of the metal foil (for example, 18×10−6/° C. for copper foil).
Etching on selective portions of each surface of metal foil sheets 25a and 25b forms circuit patterns 32a and 32b, respectively. A four-layered circuit board is thus obtained.
To manufacture a circuit board having six or more layers, a core circuit board having four or more layers is needed instead of double-sided circuit board 30. Carrying out the process repeatedly from FIGS. 6A through 6D can produce a multi-layer circuit board having six or more layers.
Prepreg sheet 21 described here has a thickness of 100 μm after being compressed.
As the demand for a thin board grows, a request for a high-quality multi-layer circuit board with slim structure and reliable connection resistance has become stronger.

Method of manufacturing multi-layer circuit board


A switch operating mechanism associated with a motor driven hydrostatic system operative in forward or reverse directions with respect to a neutral inoperative state, for rendering a motor starting circuit operative only when the hydrostatic system is in its neutral state. An axially movable switch operating shaft has a notch therein which receives a detent on the control stem of the switch, only when the shaft is in a position generally centrally between opposite limits of its axial movement, to close the switch. A centering spring urges the shaft toward its centrally disposed position.

This invention relates to improvements in prime movers, such as tractors and like vehicles, particularly those using movable control members in the power transmission mechanisms thereof. More specifically, this invention is in the nature of a control device or interlock for preventing the engine of a vehicle, such as a tractor, from being started when the driving wheels or other power operated mechanisms of the vehicle are operatively coupled to the vehicle engine. The invention is particularly adapted to vehicles such as tractors having hydrostatic drive assemblies including one or more pumps driven by an internal combustion engine, and cooperating fluid motors connected to the vehicle drive wheels or other power driven apparatus. In many cases, the engine driven pumps are of the well known wobble plate controlled variety and operate between neutral, stationary, and forward and reverse drive dispositions.
The vehicle operator, in starting the tractor engine, does not always notice whether or not the drive mechanisms are in a neutral state. If the hydrostatic system is in a drive condition, the vehicle starts to move immediately upon starting of the engine. If the operator is not prepared for sudden unexpected movement, accidents may occur. An important object of this invention is, therefore, the provision of means for preventing a vehicle engine from being started unless the power transmission mechanism of the vehicle is in a neutral nonoperative state.

Neutral start and centering device for power transmission mechanism


A composite article having blast and ballistic resistance suitable for helmets, personal protection and hard armor applications comprises a high-strain hardening elastomeric layer and a layer of continuous yarns having a tenacity of 15 grams per dtex and a modulus of at least 500 grams per dtex or an oriented polyethylene sheet layer having a modulus ten times greater in one direction than in another direction.

The present invention is directed to a composite article having a combination of blast resistance and ballistic resistance. Such composite article is particularly useful for personal protection such as for a helmet or in body armor.
U.S. Pat. No. 7,300,893 B2 discloses armor having protection against blast and ballistic damage by encapsulating or sandwiching rigid inclusions or a rigid plate in a high-strain rate hardening elastomer U.S. Pat. No. 7,938,053 B1 discloses visually transparent multilayer armor panels employing a composite including a confined high-strain rate sensitivity-hardening polymer between transparent layers and a further composite which also contains a transparent layer.
U.S. Pat. No. 8,105,510 B1 discloses a stratified composite system of armor which includes a backing of elastomeric matrix material and low-density ceramic elements arranged along a geometric plane.
A need is present for an article having a combination of improved blast resistance and ballistic resistance.
In the following sections, numbers in parenthesis pertain to reference numbers in the Figures.

Blast and ballistic improvement in helmets

THE UNITED SATES OF AMERICA AS REPRESENTED BY THE SECRETARY OF THE NAVY


Apparatus for cooling thermoplastic strands issuing from an extrusion die, the apparatus including a cooling trough between the extrusion nozzle and the granulator. The trough has two coolant drainage regions, a first being connected to a gravity drain and a second having means applying air downward through apertures in the trough. A conical separator for granulate is provided following the granulator.

This invention relates to the cooling and granulation of molten thermoplastic strands which emerge from nozzles, and the generation of dry granulate. For that purpose a slanted drainage trough can have its upper end disposed below the nozzles; with a granulator following in sequence beyond the lower end of the drainage trough. A stream of coolant is generated on the drainage trough, and the strands move from the lower end of the trough into the granulator.
Such a device is shown in FIGS. (5) and (6) of German Auslegeschrift No. 2 218 210, which also discloses means to induce drying. In accordance with FIGS. (5) and (6) a net-like transport belt is employed to receive wet granulate delivered by the granulator. While the granulate is being moved by the transport belt, it looses adherent water by the action of gravity.
Another method of drying disclosed in the Auslegeschrift directs the net-like transport belt between the end of the drainage trough and the entry of the granulator at an upward slant. A blower is disposed above the transport belt and directed towards it. Under the action of this blower, the granulate conveyed by the transport belt has adherent water blown away.

Apparatus for cooling and granulation of thermoplastic strands


Provided is an arm support of a bicycle which is configured to reduce an intensive pressure acting from a seat due to the rider's weight inclined at the seat by spreading the inclined weight to other parts. The rider can get on or off the bicycle more easily by putting his/her arms on the arm support. In the bicycle including a frame, a seat disposed at the frame, a handle for controlling the direction of the bicycle, and wheels rotatably coupled to the frame, the arm support includes: a support shaft including a coupling part fixed to the frame: a support bar disposed at an upper side of the support shaft and connected to both sides of the support shaft; and armrests coupled to the support bar so that a rider puts his/her arms thereon The armrests extend horizontally from the vertical support bars and bent toward the seat or upward to form armrest channels.

As shown in FIG. 1, a typical bicycle includes a frame 10, a seat 20 mounted on the frame 10, a handle 30 for handling the moving direction of the bicycle, wheels 40 rotatably coupled to the frame 10, pedals 50 for rotating the wheels 40, and a power transmission part 60 for transmission power from the pedals 50 to the wheel 40. Most handling devices or driving devices are installed on the frame 10.
If a rider sits on the seat 20 and rotates the pedals 50, power is transmitted from the pedals 50 to the wheels 40 so that the bicycle can be driven. In this case, the rider sitting on the seat 20 may continuously rotate the pedals 50 by applying his leg power. For this, if the rider sits on the seat 20 and moves his legs, the rider's weight may be concentrated on the seat 20, and thus his buttocks may be intensively pressed.
Due to the pressure exerted by the seat 20, blood flow in the perineal region may be reduced, and thus blood circulation may be restricted. That is, frequent and long time cycling may result in many side effects such as prostatitis.
Moreover, when riding, getting on or getting off the bicycle, a rider should always grip the handle 30 and pay attention to the handle 30, and thus comfortable and convenient cycling may not be assured. Moreover, since motions for getting on and off the bicycle are taken only by gripping the handle 30, it may be difficult to maintain body balance, and such motions may be inconvenient.


The structure of the RAM in the signal processing circuit of a digital audio tape recorder. When the reproduction mode is switched over to the recording mode, or the sampling frequency for the recording is changed to a different sampling frequency, a RAM clear signal is automatically output. At the output of the RAM clear signal, a converting circuit disposed in the route from a read address generator to an address bus is operated so as to read the digital sound data from the RAM and supply the digital sound data to a recording head and record it on a magnetic tape. Address signals only in the odd blocks of the RAM are generated and null data is serially written thereinto, thereby clearing the RAM.

1. Field of the Invention
The present invention relates to a digital audio tape recorder for recording a sound signal as digital data on a magnetic tape by using a rotary head and, more particularly, to a digital audio tape recorder which can cope with a change of a sampling frequency.
2. Description of the Related Art
With the progress of digital technique, processing of a large capacity of data is enabled and digital recording is adopted for recording various signals. In the field of sound signal recording, compact disks and the like which adopt digital recording have become widespread.
Among these apparatuses which utilize digital recording, digital audio tape recorders (DAT) which are capable of not only reproducing but also recording a sound signal have attracted attention.
DAT's are advantageous in that since a sound signal is recorded on a magnetic tape as digital data, they are free from the problems such as wow flutter, hiss noise and modulation noise, which are inevitable in analog recording, and in that since they have a wide dynamic range which can realize flat frequency characteristics in a wide frequency, recording and reproduction with a high sound quality is realized.
There are two types of DAT's. One utilizes a rotary head, and the other utilizes a fixed head. DAT's using a rotary head have been standardized and increasingly produced as manufactured goods.
In a DAT of a rotary head system, a signal is stored in each track inclined at a little over 6.degree. with respect to the direction of travel of the magnetic tape, as shown in FIG. 6.
Each track is separated into an area for recording sub codes consisting of various kinds of information necessary for reproduction, an area for recording an ATF signal for tracking, etc. as well as an area for recording digital sound data (PCM).
The rotary head is provided with two magnetic heads for tracing tracks of the magnetic tape and two tracks are traced in one revolution of the rotary head. The magnetic tape is so designed as to come into contact with the rotary head which rotates at a high speed only in the range of 90.degree..
Consequently, sound data are intermittently recorded and reproduced on and from the magnetic tape by the magnetic head, and in order to input and output continuous sound, it is necessary to convert the time axis of data.
The DAT adopts an interleave format for recording data in dispersion in order to suppress a random error or a burst error which is produced in recording data on the magnetic tape to the minimum.
In order to convert the time axis and record and reproduce data in the interleave format, RAM for storing a considerable amount of data is necessary.
In recording data, after the time axis is converted, data for two tracks are written in the RAM in the interleave format and while the data for the next two tracks are written, the data for the two tracks stored in the RAM are read out and recorded on the magnetic tape. In reproducing the data, the data read out of the magnetic tape is temporarily written into the RAM and after de-interleaving the data read out of the RAM, the time axis is converted.
The conversion between an analog sound signal and a digital sound signal is carried out by an A/D converter and a D/A converter. In DAT's, three sampling frequencies, namely, 48 kHz, 44.1 kHz and 32 kHz are prepared as a sampling frequency for sampling the digital data from a sound signal in the A/D converter, thereby enabling a long-time recording and direct transmission and reception of the digital signal to and from another audio apparatus.
Since one of these frequencies is adopted in recording or reproduction, the RAM has a capacity which can cope with the amount of data output when the sampling frequency is the highest and the same RAM copes with all the sampling frequencies.
In such a DAT, when a sound signal is recorded while reading the data which is stored in the RAM as described above and writing the data into the magnetic tape, if the sampling frequency is low, the amount of data is small and there is an area in a part of the RAM in which the data is not overwritten. As a result, if data is recorded at a low sampling frequency after reproduction and recording at a high sampling frequency is carried out, the data which is not overwritten remains in the RAM and this data is inconveniently recorded on the magnetic tape.
To prevent this, in a conventional DAT, when the sampling frequency is changed or the reproduction mode is changed into the recording mode, null data (0) is written into the entire part of the RAM while utilizing the ordinary RAM writing time, and after the contents of the RAM are cleared, data is written.
In this system, if the RAM is cleared at the start of recording, it is impossible to record data while the RAM is being cleared. It is therefore impossible to record in the RAM the data supplied during the period from the time when the command of the start of recording is issued to the time when the clearing of the RAM is finished. In other words, the sound data supplied during this period is discarded.
In the case of adopting the interleave recording system in which recording is completed by recording data in two tracks, since the data for two tracks are first written into the RAM and the actual recording of the data on the magnetic tape is begun when the data for the next two tracks are input, the starting of recording data on the magnetic tape is further delayed.
The rotary head having two magnetic heads rotates at 2,000 rpm. One revolution takes about 30 msec and in this period the writing or reading of data for two tracks is finished.
Therefore, the RAM is cleared in the first 30 msec from the issue of the command of recording, and the data itself is discarded. In the next 30 msec, data is written into the RAM and the recording of the data on the magnetic tape is started after these processings are finished, namely, 60 msec after the issue of command of recording.
That is, the data for 30 msec is discarded and the recording of data on the magnetic tape is started 60 msec after the issue of command of recording.
In an ordinary operation, recording is often continued in the same mode (at the same sampling frequency). In other words, it is often the case that the clearing of the RAM before the start of recording is unnecessary.
Since it is impossible to record data while the RAM is being cleared, it is impossible to record in the RAM the data supplied during the period from the time when the command of the start of recording is issued to the time when the clearing of the RAM is finished. In other words, the sound data supplied during this period is discarded. It is therefore demanded to avoid unnecessary RAM clearing as much as possible.

Signal processing circuit of digital audio tape recorder


A pumping apparatus 10 for dispensing multiple component fluid material. The apparatus 10 includes at least first and second flexible tubes. The tubes each have an inlet and an outlet, and each of the inlets is supplied with a different component of the fluid material. A roller or rollers are provided for pressurized engagement with the tubes. The stop plate is engaged with the tubes at a location opposing the pressurized engagement of the roller. A driver mechanism independently moves the roller in pressurized engagement with the tubes, opposed by the stop plate, in a linear direction. Such linear movement carries the desired and variable amounts of fluid material to the tube outlets. An engagement frame supports the tubes, roller, stop plate and driver mechanism. A mixing reservoir is provided having multiple inlets, each of which is engaged with a flexible tube outlet, and a single outlet, such that the fluid material components are combined within the mixing reservoir and provided to the single outlet. A static mixer may also be provided which is supplied with mixed fluid material via the single outlet of the mixing reservoir for further mixing of the components of the fluid material.

Currently available dispensing devices for dispensing fluid material, and in particular multiple component adhesive materials, in predetermined desired ratios often use a conventional cartridge type dispenser which includes a piston engaged within the cartridge to dispense the desired amount of fluid. Such devices are often used in connection with the mixing of multiple component reactive materials containing volatile organic compounds or VOC's. Unfortunately, such devices have a tendency to leak, and do not provide consistent repeatable shot sizes of each of the material components.
Further, such prior art devices typically do not pump the different adhesive material components in various ratios or desired amounts. As a result, premixing of the separate components in the desired formula is required prior to pumping. Such premixing exposes the pump operator to component materials which may give off undesirable fumes, and which are difficult to clean up in the event a spill occurs during the premixing operation. Additionally, the premixing of such materials also results in an increased amount of waste product due to the reduced life of the materials once exposed, for example in open containers, for mixing.
Available prior art devices also do not allow the material components being pumped to be changed to different materials, without further cleaning of the devices. Moreover, the devices typically force the component materials from their respective cartridges under pressure. Such pressurized application can additionally result in leakage and inconsistent shot sizes of the desired component materials being applied. Although attempts have been made to deliver such material components individually using a fixed gear ratio assembly, such fixed gear ratio devices do not maintain the desired ratios of component materials for materials having different viscosities.


An electronic component includes at least one coil including a winding part and lead-out end parts at both ends thereof, and a magnetic molded body having a mounting surface with the coil incorporated therein. The lead-out end parts are led out toward the mounting surface such that end surfaces of the lead-out end parts are arranged on the same plane as the mounting surface.

An electronic component having a coil sealed with a magnetic sheet is conventionally widely used. In the molded coil described in Japanese Laid-Open Patent Publication No. 2011-3761, flat plate-shaped magnetic bodies sandwiching a plurality of coils are further pressurized to seal the coils. The magnetic bodies including the coil are then cut into a predetermined shape to acquire a molded coil. The molded coil has both ends of the coil led out from side surfaces thereof and connected to external terminals. The external terminals are formed over the side surfaces and a mounting surface of the molded coil.

Electronic component and method of manufacturing the same


Access openings in a fuel cell assembly are isolated from their surroundings by use of a closure member that is actuated by the pressure in a fluid stream within the fuel cell assembly. An isolating apparatus prevents undesirable water loss or gain in certain fuel cell types and protects the fuel cell assembly from contamination.

The present invention relates to a method and apparatus for isolating a fuel cell assembly from its surroundings, such as for protection against dehydration during shutdown or for other purposes, such as protection against contaminants.
Electrochemical fuel cells convert reactants, namely, fuel and oxidant, into reaction products and in the process generate electric power. In a typical fuel cell using hydrogen gas as fuel and oxygen or compressed air as oxidant, the reaction product is water.
Solid polymer fuel cells typically employ a membrane electrode assembly (MEA) comprising a solid polymer electrolyte or ion exchange membrane disposed between two electrode layers. The membrane, in addition to being an ion conductive (typically proton conductive) material, also acts as a barrier for isolating the reactant fluid streams from each other. The MEA is interposed between two electrically conductive separator plates impermeable to the reactant flow streams and having flow channels forming flow fields to direct the fuel and oxidant to the respective electrode layers.
In a fuel cell stack, a plurality of fuel cells are connected together to increase the overall output power of the assembly. The fuel cell stack is interposed between a pair of end plates have inlet and outlet ports associated therewith for feeding and exhausting the oxidant and fuel fluid streams, respectively. The end plates may also have inlet and outlet ports associated therewith for flowing a coolant stream through the stack.
It is desirable that the ion-exchange membrane in the fuel cell stack be kept moist to maintain adequate ionic conductivity and to reduce structural damage that may result if the membranes are allowed to become too dry. It is known that leaks in membranes may occur near reactant stream inlet ports. Such leaks may be caused or worsened by membrane dehydration during fuel cell stack operation, thereby resulting in the formation of cracks or holes.
In a phosphoric acid electrolyte fuel cell stack, it is desirable to prevent water from entering the stack during shutdown periods. Additionally, it is desirable in some applications to protect the fuel cell stack from contaminants or other hazards, such as exposure to salt water, particularly in marine applications.
An improved method isolates an electrochemical fuel cell assembly from its surroundings, the fuel cell assembly having an access opening formed therein. The access opening is either of a reactant stream inlet port or a reactant stream outlet port for directing a working fluid stream (such as, for example, a coolant stream) to or from the fuel cell stack or other component in the fuel cell assembly (for example, a reactant stream humidifier). In a preferred embodiment, the access opening is an opening formed in an enclosure containing the fuel cell assembly. The improved method comprises the steps of:
(a) providing the access opening with a closure member that is normally biased to a closed position in which the access opening is closed, the closure member having a pressure activated actuator for urging the closure member to an open position when the actuator is exposed to pressure; and
(b) operatively connecting the actuator to a fluid stream of the fuel cell assembly such that the actuator is exposed to fluid pressure of the fluid stream for urging the closure member to the open position, thereby opening the access opening.
In preferred embodiments, the access opening is an oxidant stream inlet or an oxidant stream outlet, and the fluid stream that provides the actuating pressure is a fuel stream.
An improved fuel cell assembly has an access opening formed therein through which the assembly is exposed to its surroundings. The improved assembly comprises a closure member that is movable between an open position and a closed position, the closure member being operatively associated with the access opening and normally biased to the closed position such that when the access opening is closed the fuel cell assembly is isolated from its surroundings. In operation, the closure member preferably includes a pressure-activated actuator for urging the closure member to the open position when the actuator is exposed to pressure. The actuator optionally comprises a conduit fluidly connected to a fluid stream of the fuel cell assembly for exposing the actuator to the fluid stream pressure and urging the closure member to the open position, thereby opening the access opening.
An improved fuel cell assembly also comprises a solid polymer electrolyte fuel cell comprising first and second fluid flow channels and an isolation valve that is switchable between a closed position and an open position for, respectively, closing and opening said first fluid flow channel. The valve is normally biased to the closed position for closing the first fluid flow channel during shutdown of the fuel cell assembly. The valve further includes an actuator that is responsive to fluid pressure in the second fluid flow channel during start up of the fuel cell assembly for switching the valve to the open position.

Method and apparatus for isolating a fuel cell assembly from its surroundings


A pneumatic active suspension apparatus is provided wherein, when a sprung vertical acceleration (ZG), which causes a wafting phenomenon perceptible by a person in a vehicle, occurs during travel of the vehicle, supply/discharge of air to/from air spring chambers of suspension units is carried out for a supply/discharge control time determined based on the maximum value (ZGmax) of the sprung vertical acceleration. The supply/discharge control is started at an advanced time based on the sprung acceleration whose phase is advanced by 90 degrees from that of the sprung velocity, to thereby produce a force acting to cancel out the sprung vertical velocity at proper timing. As a result, the operation delay of the suspension apparatus is compensated for and the sprung vertical motion is suppressed.

The present invention relates to a fluid active suspension apparatus using compressible fluid as an operating medium and to an operation control method for the suspension apparatus.
In order to suppress vibrations of a vehicle body caused by vibration input from the road surface, it is known in the art to employ an active suspension apparatus in which positive damping is effected by supplying and discharging compressible fluid to and from fluid spring chambers. U.S. Pat. No. 4,856,815, for example, discloses a pneumatic suspension apparatus which is designed to keep the vehicle body horizontally positioned even when the vehicle is traveling on a wavy road. In this suspension apparatus, air is supplied to and discharged from air spring chambers of suspension units arranged between the vehicle body and respective wheels, in accordance with the output of a stroke sensor representing the relative displacement between the vehicle body and the wheels (more generally, between sprung and unsprung sides of the vehicle), to thereby control the stroke of the suspension units so that the sprung side can be held horizontally even when the unsprung side is making a vertical (up-and-down) motion in response to change in the level of the road surface.
More specifically, in this suspension apparatus, when the stroke sensor output becomes greater than or equal to a predetermined value, a supply valve is opened for a predetermined time to actively supply air to the air spring chamber if the air spring is expanding, and a discharge valve is opened for a predetermined time to actively discharge air from the air spring chamber if the air spring is contracting.
This type of suspension apparatuses can suppress vertical motion of the vehicle body, but is not sufficiently effective in reducing the force causing the vertical motion of the vehicle body itself. Thus, when sprung resonance conditions are fulfilled, in particular, bouncing vibration, which gives a strange feeling to a person in the vehicle, occurs in a sprung resonance region.
As a control technique for reducing such bouncing vibration, the skyhook damper theory is known in the art. According to this theory, a force proportional to the vertical velocity of the vehicle body is produced and is acted in a direction to cancel out the vertical velocity, to thereby suppress vibration of the vehicle body caused by the vibration transmitted from the road surface. So far, the skyhook damper theory is embodied in an active suspension apparatus using incompressible fluid as an operating medium.
For example, U.S. Pat. No. 5,089,966 discloses a hydraulic active suspension apparatus using oil as the operating medium. In this suspension apparatus, the vertical velocity of the vehicle body is obtained by detecting the vertical acceleration of the vehicle body and integrating the detected acceleration, and an oil pressure proportional to the vertical velocity is supplied to actuators, to thereby damp vibration of the vehicle body.
This type of hydraulic active suspension apparatuses comprises, as its indispensable elements, a hydraulic pressure source including a pump, a reservoir tank, and a pump accumulator for eliminating the pumping pulsation, a hydraulic control system including an actuator, a proportional control valve for applying a desired pressure of oil from the hydraulic pressure source to the actuator, and a main accumulator disposed between the proportional control valve and the actuator for accumulating the hydraulic pressure, and a controller for controlling the hydraulic control system.
This hydraulic active suspension apparatus is effective in carrying out damping based on the skyhook damper theory, but it requires a proportional control valve having high operation accuracy and high operation response, which leads to an increase of the cost. Further, since oil is used as the operating fluid, the hydraulic pressure source is large in size, requiring much space for the suspension apparatus and increasing the weight of the vehicle.
In the pneumatic active suspension apparatus, on the other hand, since air serving as the operating fluid has compressibility, it is difficult to control the internal pressure of the air spring chamber of the apparatus by using, e.g., a proportional control valve. Further, the pneumatic suspension apparatus is low in operation response, and it is, therefore, difficult to operate an actuator such as the air spring chamber at a proper time so as to produce a force for suppressing vibration of the vehicle body. For this reason, no skyhook damper theory-based control technique applicable to the pneumatic active suspension apparatus has been developed yet.
The aforementioned hydraulic active suspension apparatus capable of skyhook damper theory-based active control uses three or four sensors for detecting the vertical acceleration of the vehicle body, in order to acquire control information for use in the active control. The vertical acceleration sensors are, however, expensive, and an increase in the number of sensors generally requires more thoughtful consideration on the installation of sensors, correction of the sensor output characteristics in relation to temperature, configuration of a fail-safe system for troubleshooting the sensors, etc. Accordingly, the conventional apparatus using three or four vertical acceleration sensors is costly.

Fluid active suspension apparatus and operation control method therefor

Mitsubishi Jidosha Kogyo Kabushiki Kaisha


A turn down ratio (TDR) damper which controls an amount of gas and air flowing in the TDR damper and deliver the controlled gas and air to a turbo fan is disclosed. The TDR damper includes: air passages comprising a first air passage and a second air passage, the first air passage and the second air passage separately formed so that the air move through each path; gas passages comprising a first gas passage and a second gas passage, the first gas passage and the second gas passage separately formed so that the gas move through each path; and opening and closing means for opening and closing the second air passage and the second gas passage at the same time. The air passages and the gas passages may be separately formed and reached outlets connected to the turbo fan so that the air and gas may be delivered to the turbo fan through a separate path.

1. Field of the Invention
The present invention relates to a turn down ratio (TDR) damper, and more particularly, to a TDR damper which may efficiently deliver gas and air while controlling an amount of gas and air supplied to a burner such as a boiler or a water heater.
2. Description of the Related Art
In general, a burner such as a boiler and a water heater used when using cold water and hot water may include an oil boiler, a gas boiler, an electric boiler, and a water heater according to supplied fuel and may be used for various purposes according to an installation condition. Generally, in such burners, in particular, a gas boiler and a water heater, a Bunsen burner or a premixed burner is used to burn gas fuel. Here, a combustion process of the premixed burner is carried out in such a way that gas and air is mixed with the mixture ratio in an optimal combustion condition and then the mixture air (gas+air) is supplied.
In addition, a performance of a burner is evaluated by a Turn Down Ratio (TDR). The TDR is the 'ratio of the maximum gas consumption to the minimum gas consumption' in gas burners in which an amount of gas is variably controlled. For example, when the maximum gas consumption is 50,000 kcal/h and the minimum gas consumption is 10,000 kcal/h, the TDR is 5:1.
In a gas boiler and a water, when the TDR increases, convenience in heating and a use of hot water increases. That is, when a burner is operated in a low TDR (that is, the high minimum gas consumption) and low load of heating and hot water, the burner is frequently turned on and off. Accordingly, a temperature deviation increases while controlling and durability of the burner decreases. In order to improve such matter, various methods to increase the TDR of the burner have been developed. One of the methods is disclosed in Korean Patent Publication No. 10-1308936 (hereinafter, referred to as 'prior art').
FIG. 1 illustrates moving paths of gas and air in a prior art.
Referring to FIG. 1 and Korean Patent Publication No. 10-1308936, air and gas moves as shown by arrows in FIG. 1 and are mixed in an outlet. Then, the mixed air and gas is delivered to a turbo fan. However, in a structure as in FIG. 1, gas moves in a vertical direction, whereas air moves in a horizontal direction above the gas. Thus, air may prevent an inflow of gas and accordingly, gas is not actually flowed in the burner of FIG. 1.