Abstract: In a power converter, an overvoltage suppression function of low cost and high reliability is provided. The power converter has a power conversion circuit, when driving a motor, for converting power from a battery and supplying it to the motor and when the motor generates power, converting the generated power of the motor and supplying it to the battery for storage of electricity and a drive circuit for driving the power conversion circuit. The power conversion circuit includes a plurality of paired switching elements, in which one of each paired switching elements is arranged on an upper arm, and the other is arranged on a lower arm, and each pair corresponds to each phase of the motor. The drive circuit, when the voltage applied to the power conversion circuit is increased, turns on all the switching elements on one arm, turns off all the switching elements on the other arm, thereby short-circuits the output terminals of the motor.

Abstract: A current sensing device for sensing current flowing through a MOSFET has a voltage divider circuit composed of a series circuit of a first resistor and a second resistor having different resistance temperature coefficients, with a voltage division ratio designed to change depending on temperature. The sensing device is connected between a source and a drain of said MOSFET. A sensing circuit takes out the source-to-drain voltage divided with the voltage divider to sense the current flowing through the MOSFET.

Abstract: An A.C. generator has a rotor that is equipped with a permanent magnet and a field coil. The output of the A.C. generator charges the high-voltage battery. Voltage of the high-voltage battery is stepped-down by a DC/DC converter and supplied to the low-voltage battery. When the motor controller detects that the field coil has not been energized, the higher-rank controller switches so as to generate power by means of the permanent magnet of the A.C. generator and charge the low-voltage battery. This mechanism enables power to be generated when a circuit malfunctions. Thereby, a power supply system for vehicle can generate power when a circuit malfunctions so that the driver on the vehicle can drive the vehicle to a repair shop.

Abstract: A current sensor has a power MOSFET Q1, connected between an electric load and a power supply, for controlling current that flows through said electric load, a mirror MOSFET Q2, connected in parallel to said power MOSFET Q1, in which a portion of the current flowing through said power MOSFET flows, and a current detection resistor RC connected between a source electrode of said power MOSFET and a source electrode of said mirror MOSFET. An inverting amplifier circuit CP of the current sensor 3 inverts and amplifies the voltage signal, which has been converted to voltage by the current detection resistor RC, and outputs the signal, thereby converting positive and negative voltages generated across the current detection resistor RC to a positive voltage.

Abstract: Solving Means: A field coil current and a stator current are controlled by a controller. The stator current is controlled under vector control and is controlled so that the phase keeps an efficient motor zone. In a case of rated power generation, when the motor speed is low, the phase current and field coil current are increased to reserve the generated power. And, as the speed is increased, the phase current is decreased to reduce the copper loss, while in place of decreasing the phase current, the field coil current is kept high to reserve the generated power. Thereafter, as the speed is increased more, the field coil current is decreased to reduce the iron loss, while in place of decreasing the field coil current, the phase current is increased to reserve the generated power.

Abstract: The present invention relates to a method for continuous production of a water-absorbent resin by use of an continuous polymerization device having a charge part of a monomer aqueous solution; an endless belt on which the monomer and a hydropolymer formed are conveyed; and a discharge part of the hydropolymer, wherein the continuous polymerization device has side walls and a ceiling, and the space ratio in the device represented by the equation, “space ratio in the device=B/A”, is in the range of 1.2 to 20. In the equation, A is a maximum cross-sectional area (cm2) of the hydropolymer during the polymerization in the width direction of the endless belt, and B is a maximum cross-sectional area (cm2) of the space between the endless belt of the continuous polymerization device and the ceiling of the continuous polymerization device in the width direction of the endless belt.

Abstract: The present invention provides a semiconductor device which reduces an inductance of wiring for bridge-connecting semiconductor switches and realizes a reduction in size. Within the semiconductor device formed are two controllable bridge-connected semiconductor switches 13a and 13b, an output terminal, positive/negative polarity DC terminals 2 and 3, and an insulating substrate 15a in which conductor layers 12, 17 and 19 having a conductor section and in an inner layer for bridge-connecting the semiconductor switches to the DC terminals on a surface thereof and insulating layers 16 and 18 are alternately laminated. The surface and inner-layer conductor layers 12 and 17 which interpose the insulating layer 16 therebetween are electrically connected by a conductor 20 passing through the insulating layer 16 interposed between the conductor layers 12 and 17.

Abstract: The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.

Abstract: In a power converter, an overvoltage suppression function of low cost and high reliability is provided. The power converter has a power conversion circuit, when driving a motor, for converting power from a battery and supplying it to the motor and when the motor generates power, converting the generated power of the motor and supplying it to the battery for storage of electricity and a drive circuit for driving the power conversion circuit. The power conversion circuit includes a plurality of paired switching elements, in which one of each paired switching elements is arranged on an upper arm, and the other is arranged on a lower arm, and each pair corresponds to each phase of the motor. The drive circuit, when the voltage applied to the power conversion circuit is increased, turns on all the switching elements on one arm, turns off all the switching elements on the other arm, thereby short-circuits the output terminals of the motor.

Abstract: The present invention provides: a production process for a particulate water-absorbent resin with high productivity, which production process is carried out in such a manner that the particulate water-absorbent resin will contain particles with particle diameters of 150 to 850 ?m (but excluding 850 ?m) in an amount of not smaller than 75 weight % of the particulate water-absorbent resin after the pulverization step or after the pulverization step and the drying step even if the adjustment of the particle diameters is not carried out by the sieving classification procedure; a novel particulate water-absorbent resin having high properties; and a sanitary material comprising this particulate water-absorbent resin.

Abstract: The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.

Abstract: A positive side conductor and a negative side conductor of an input terminal electrically connected to semiconductor elements, are electrically insulated from each other, and are laminated with each other, and the input terminal having such a laminated structure, an output terminal and substrates mounted thereon the semiconductor elements are arranged in a checkered pattern in a container. Further, the semiconductor elements mounted on the substrates, the input terminal and the output terminal are electrically connected to one another so as to obtain a loop-like electric path on a conductive member, thereby it is possible to aim at miniaturizing the power conversion apparatus and lowering the inductance thereof.

Abstract: The invention is intended to provide a control device for a vehicular AC motor, which has higher efficiency of voltage utilization in a power running mode and has higher efficiency of electricity generation in an electricity generation mode. The motor control device comprises rectifying devices and switching devices for three phases, which are connected between a DC power source and armature coils of an AC motor operatively coupled to an internal combustion engine. The motor control device has the inverter function of converting a DC power from the DC power source into an AC power and supplying the AC power to the armature coils, and the converter function of converting an AC power generated by the AC motor into a DC power and supplying the DC power to the DC power source.

Abstract: An object of the present invention is to make it possible, in order to form the fine powder of the water-absorbent resin into a water-absorbing material having particle diameters favorable for practical use, that a water-absorbing material which has high agglomeration strength and is excellent in the quality performances is obtained at a low cost with good efficiency without causing the problems of the adhesion to such as treatment apparatus.

Abstract: A method of manufacturing a water-absorbing shaped body that is produced easily without using a thickening agent. Light is radiated onto an aqueous solution including a photo polymerization initiator and a water-soluble ethylenically unsaturated monomer. When a desired viscosity is attained, radiation of the light is stopped temporarily. Then, the aqueous solution, which is thickened, is shaped into a desired shape. Thereafter, polymerization is completed by radiating light again.

Abstract: In a production process for a water-absorbent resin, comprising the steps of: blending a liquid material and a water-absorbent resin; and heating the resultant mixture in order to produce a modified water-absorbent resin, the present invention is to provide: a method for uniformly and efficiently treating a water-absorbent resin favorably in view of industry, and as a result, a good-balanced water-absorbent resin having various excellent properties, such absorption capacity without a load, absorption capacity under a load, and single-layer absorption capacity under a load in contact with an aqueous liquid. The production process comprises the step of spray-blending a water-absorbent resin (A) and a liquid material (B) with a blending apparatus equipped with a spray nozzle (C), wherein the liquid material (B) is sprayed from the spray nozzle (C) and its spray pattern is a circular and hollow cone shape or a double-convex-lens and elliptic cone shape.

Abstract: A current sensor has a power MOSFET Q1, connected between an electric load and a power supply, for controlling current that flows through said electric load, a mirror MOSFET Q2, connected in parallel to said power MOSFET Q1, in which a portion of the current flowing through said power MOSFET flows, and a current detection resistor RC connected between a source electrode of said power MOSFET and a source electrode of said mirror MOSFET. An inverting amplifier circuit CP of the current sensor 3 inverts and amplifies the voltage signal, which has been converted to voltage by the current detection resistor RC, and outputs the signal, thereby converting positive and nega tive voltages generated across the current detection resistor RC to a positive voltage.

Abstract: The present invention provides a semiconductor device which reduces an inductance of wiring for bridge-connecting semiconductor switches and realizes a reduction in size. Within the semiconductor device formed are two controllable bridge-connected semiconductor switches 13a and 13b, an output terminal, positive/negative polarity DC terminals 2 and 3, and an insulating substrate 15a in which conductor layers 12, 17 and 19 having a conductor section and in an inner layer for bridge-connecting the semiconductor switches to the DC terminals on a surface thereof and insulating layers 16 and 18 are alternately laminated. The surface and inner-layer conductor layers 12 and 17 which interpose the insulating layer 16 therebetween are electrically connected by a conductor 20 passing through the insulating layer 16 interposed between the conductor layers 12 and 17.

Abstract: There is provided: a production process for a water-absorbing agent having stable properties in a short time; and a water-absorbing agent. The production process comprises the step of blending an acid-group-containing water-absorbent resin powder with a noncrosslinkable water-soluble inorganic base and/or an irreducible alkaline-metal-salt pH buffer and further with a dehydratable crosslinking agent reactable with the acid group, thereby subjecting the resin powder to crosslinking treatment, or comprises the step of blending an acid-group-containing water-absorbent resin powder with the above base and/or pH buffer and further with a crosslinking agent reactable with the acid group, thereby subjecting the resin powder to crosslinking treatment, wherein the resin powder has a weight-average particle diameter of 300 to 600 &mgr;m wherein the ratio of fine powders having particle diameters of not larger than 150 &mgr;m in the resin powder is not more than 10 weight %.

Abstract: There is disclosed a process to uniformly and rapidly carry out the mixing of a monomer liquid and a polymerization initiator and thus for the resulting polymer not to adhere to the inner surface of the piping or the inside of the apparatus in an art of producing a water-absorbent resin by continuously mixing the monomer liquid and the polymerization initiator together and thereby carrying out polymerization. This process comprises the steps of: (a) continuously supplying a monomer liquid 20 to such as a supply pipe 10 to continuously stir the monomer liquid 20 in the supply pipe 10 with such as a stirring apparatus 12; (b) causing a polymerization initiator 30 to join into a flow of the monomer liquid 20 being in a stirred state, thereby obtaining a mixed liquid 40 of the monomer liquid 20 and the polymerization initiator 30; and (c) continuously supplying the mixed liquid 40 from the supply pipe line 10 to a polymerization apparatus to cause the mixed liquid 40 to run a polymerization reaction.