Abstract: The present invention provides a boost switching power supply with low switching loss. The boost switching power supply of the present invention includes a coil portion 3a and a first diode 4 that are serially connected between one terminal of a DC power source 2 and one terminal of a first capacitor 5 for smoothing, a first switching element 8 connected between a node A where the coil portion 3a and the first diode 4 are connected and the other terminal of the DC power source 2, a second magnetic element 7 and a second switching element 9 that are serially connected between the node A and the other terminal of the DC power source 2, and a second diode 10 and a second capacitor 11 that are serially connected between a node where the second magnetic element 7 and the second switching element 9 are connected and the node A.

Abstract: A chair includes a seat portion 1(1B), a seat support 2(2B) supporting the seat portion 1, a rear seat support 3(3B) extending rearwardly upwardly relative to the seat support 2(2B), and a slide mechanism X1 (moving mechanism XB) for causing the seat portion 1(1B) to slide back and forth relative to the seat support 2 (2B). The chair is provided with a locking mechanism 100C for locking the seat portion 6C at a desired position in the fore-and-aft direction selectively, and a lever 110C for operating the locking mechanism 100C, the lever 110C being located at a position allowing the lever 110C to move together with the seat portion 6C in the fore-and-aft direction.

Abstract: A chair 1 allowing a person sitting thereon to move a part of the person's body above the waist which corresponds to the backrest of the chair is provided having a backrest portion located behind a seat portion, the backrest portion being divided into backrest upper frames 55 and backrest lower frames 50, wherein a first state which allows the whole backrest frame 5 to incline rearwardly and a second state which allows the backrest upper frames 55 to incline rearwardly relative to the backrest lower frames 50 are assumed, the first state and the second state being switchable to each other.

Abstract: The present invention provides a boost switching power supply with low switching loss. The boost switching power supply of the present invention includes a coil portion 3a and a first diode 4 that are serially connected between one terminal of a DC power source 2 and one terminal of a first capacitor 5 for smoothing, a first switching element 8 connected between a node A where the coil portion 3a and the first diode 4 are connected and the other terminal of the DC power source 2, a second magnetic element 7 and a second switching element 9 that are serially connected between the node A and the other terminal of the DC power source 2, and a second diode 10 and a second capacitor 11 that are serially connected between a node where the second magnetic element 7 and the second switching element 9 are connected and the node A.

Abstract: A power conversion apparatus capable of reducing the conduction loss to achieve high efficiency yielding a downsized and weight-reduced apparatus and a method for driving such a power conversion apparatus is disclosed. A power conversion apparatus comprising a switching-element driving circuit which includes a current transformer having a primary coil connected to an current control type switching element, and a driving-current generating circuit formed of a secondary coil of the current transformer and a rectifying circuit connected to the secondary coil, wherein an output current generated in the driving-current generating circuit is supplied to the switching element as a driving current of the switching element, and a method for driving the switching element of such a power conversion apparatus are disclosed.

Abstract: A chair 1 allowing a person sitting thereon to move a part of the person's body above the waist which corresponds to the backrest of the chair is provided having a backrest portion located behind a seat portion, the backrest portion being divided into backrest upper frames 55 and backrest lower frames 50, wherein a first state which allows the whole backrest frame 5 to incline rearwardly and a second state which allows the backrest upper frames 55 to incline rearwardly relative to the backrest lower frames 50 are assumed, the first state and the second state being switchable to each other.

Abstract: A chair comprising a seat (1(1B)), a seat support (2(2B)) for supporting the seat (1), a rear seat support (3(3B)) extending upwardly rearwardly of the seat support (2(2B)), and a slide mechanism (X1) (moving mechanism (XB)) for sliding the seat (1(1B)) back and forth with respect to the seat support (2 (2B)). Further, a seat (6C) is provided with a fixing mechanism (100C) for fixing it at a desired longitudinal position, and a lever (110C) for operating the fixing mechanism (100C) is installed at a position which allows longitudinal movement thereof together with the seat (6C).

Abstract: In order to improve operationality to produce functions, to prevent an assembling or disassembling procedure from being complicated and to simplify a structure of a chair of multi-function, a chair having a plurality of operating portions to adjust a height of a back or a seat or to adjust a rocking motion mechanically is so arranged that each of more than two operating portions as some or all of the operating portions is made to rotate around a predetermined shaft respectively, each shaft of the operating portions is arranged in a line, and more than two operating portions as some or all of the operating portions are arranged in a line and the chair comprises an operation receiving portion as a mechanism to work each mechanism directly and a link means that connects the operating portion and the operation receiving portion, some or all of the adjusting portions that are arranged in the link means in order to adjust a motion range of the operation receiving portion that works with operation of the operating p

Abstract: The present invention discloses a power conversion apparatus comprising a control circuit for generating a switching signal at the timing allowing soft-switching to be achieved, and free from any occurrence of ripple. The power conversion apparatus includes a first main switch (Q1) and a second main switch (Q2) which are connected in series with each other. One of the ends of the first main switch is connected with the positive side of a DC power supply, and one of the ends of the second main switch is connected to the negative side of the DC power supply. A diode (D1, D2) is connected in parallel with each of the main switches so as to become reverse biased with respect to the DC power supply. A main-switch snubber capacitor (C1, C2) is connected in parallel with each of the main switches. A load is connected with the junction between the pair of main switches, and the main switches are controllably switched according a switching signal from a control circuit to generate an output.

Abstract: In a power conversion apparatus using a semiconductor switching element, a collector-emitter voltage detecting device is provided to detect the collector-emitter voltage in the semiconductor switching element in the power conversion apparatus in order to comprehensively reduce switching loss and conduction loss arising in a switching element. A base current supplied to the switching element is controlled based on the detected collector-emitter voltage so as to control the collector-emitter voltage or control a regenerative power to be transmitted from a switching element driving power supply to an external auxiliary power supply or the like. This provides an optimum driving in consideration of factors including dispersion in a specific current amplification factor (hfe) of the switching element, variance in the hfe caused by temperature, and variance in the hfe to a current flowing through the switching element, for reducing a sum of conduction loss and driving power of the switching element.

Abstract: It is an object of the invention to provide a current sensor apparatus that reduces measurement errors resulting from variations in a position of a current path passing through the space inside a magnetic yoke. The current sensor apparatus comprises a ring-shaped magnetic yoke (2) surrounding a current path (1), part of the yoke having a gap (3), and a magnetic sensor element (4) placed in the gap (3) of the magnetic yoke (2). The magnetic sensor element (4) detects a magnetic field in the gap (3) generated by a current flowing through the current path (1) to measure the current flowing through the current path (1). The current sensor apparatus further comprises a magnetic field interrupter (5), placed between the current path (1) and the gap (3), for interrupting a magnetic field corresponding to a magnetic flux generated by the current passing through the current path (1) and not passing through the magnetic yoke (2), so that the magnetic field would not reach the magnetic sensor element (4).

Abstract: The present invention discloses a power conversion apparatus comprising a control circuit for generating a switching signal at the timing allowing soft-switching to be achieved, and free from any occurrence of ripple.

Abstract: A switching circuit for a power conversion apparatus capable of reducing conduction loss to provide a higher efficiency, and achieving downsizing and weight-reduction and higher driving frequency based on the improved efficiency is disclosed. A driving transistor is connected to a switching main transistor to supply a driving power for ON-OFF driving thereto, and an auxiliary power source composed of a current transformer is provided between the main transistor and the driving transistor. An auxiliary transistor having a lower switching loss than that of the main transistor is connected in parallel with the main transistor to form a main switch in combination with the main transistor. A current-driven type transistor serves as the main transistor, and voltage-driven type transistors serve as both of the driving transistor and the auxiliary transistor.

Abstract: In a power conversion apparatus using a semiconductor switching element, a collector-emitter voltage detecting device is provided to detect the collector-emitter voltage in the semiconductor switching element in the power conversion apparatus in order to comprehensively reduce switching loss and conduction loss arising in a switching element. A base current supplied to the switching element is controlled based on the detected collector-emitter voltage so as to control the collector-emitter voltage or control a regenerative power to be transmitted from a switching element driving power supply to an external auxiliary power supply or the like. This provides an optimum driving in consideration of factors including dispersion in a specific current amplification factor (hfe) of the switching element, variance in the hfe caused by temperature, and variance in the hfe to a current flowing through the switching element, for reducing a sum of conduction loss and driving power of the switching element.

Abstract: It is an object of the invention to provide a magnetic sensor and a current sensor that exhibit high performance at low costs. A magnetic sensor has a magnetic core (1) having a magnetic saturation property and a sensor coil (2) wound around the magnetic core (1). An end of a detection coil (20) is connected to an end of the sensor coil (2). The other end of the detection coil (20) is grounded. The magnetic sensor further comprises a drive circuit (3) and a detection circuit (4). The drive circuit (3) has a series resonance circuit part of which is made up of the sensor coil (2). To the sensor coil (2) the drive circuit (3) supplies a resonance current flowing into the series resonance circuit as an alternating current that allows the magnetic core (1) to reach a saturation region. The detection circuit (4) detects a magnetic field to be measured by detecting variations in resonance current flowing through the sensor coil (2).

Abstract: A switching circuit for a power conversion apparatus capable of reducing conduction loss to provide a higher efficiency, and achieving downsizing and weight-reduction and higher driving frequency based on the improved efficiency is disclosed. A driving transistor is connected to a switching main transistor to supply a driving power for ON-OFF driving thereto, and an auxiliary power source composed of a current transformer is provided between the main transistor and the driving transistor. An auxiliary transistor having a lower switching loss than that of the main transistor is connected in parallel with the main transistor to form a main switch in combination with the main transistor. A current-driven type transistor serves as the main transistor, and voltage-driven type transistors serve as both of the driving transistor and the auxiliary transistor.

Abstract: This PWM inverter apparatus includes a first and second current control type semiconductor switching elements connected in series which are connected in parallel to a DC power supply. An output is generated by alternately switching the first and second semiconductor switching elements. Resistive semiconductor switching elements having a higher switching speed than the first and second semiconductor switching elements and a resistance-to-current characteristics producing a voltage drop are respectively connected in parallel to respective the first and second semiconductor switching elements.

Abstract: A camera includes a plurality of photosensors disposed on an imaging surface. The photosensors separately output respective photodetection signals, and are grouped into a plurality of photosensitive units each including at least two of the photosensors. The photosensors of each of the photosensitive units have respective detection wavelength ranges which do not overlap one another. The photodetection signals outputted from selected ones of the photosensors of each of the photosensitive units are used in performing spectrum analysis. R (red), G (green), and B (blue) signals are synthesized from the photodetection signals outputted from the photosensors of each of the photosensitive units and are used in displaying an ordinary color image.

Abstract: A premixed combustor for a gas turbine, comprises, a combustion chamber for burning a fuel with an air therein, at least two premixed fuel/air mixture outlets which are juxtaposed with each other, and through each of which a premixed fuel/air mixture flows out into the combustion chamber, and a flow deflection member arranged between the premixed fuel/air mixture outlets, urging the permixed fuel/air mixture from one of the premixed fuel/air mixture outlets to go away from another one of the premixed fuel/air mixture outlets, and terminating in the combustion chamber so that the premixed fuel/air mixture from the one of the premixed fuel/air mixture outlets is permitted to move toward the premixed fuel/air mixture flowing out from the another one of the premixed fuel/air mixture outlets after going away from the another one of the premixed fuel/air mixture outlets.