Abstract: A power conversion apparatus includes main circuits, in which switching elements are connected in parallel with diodes, respectively. An auxiliary circuit, which is formed of a series-connected second switching element and a capacitor, is connected in parallel with the diode operating as a freewheeling diode. The switching element of the main circuit, which is opposite to the auxiliary circuit, is set to turn on at a reference time. The second switching element of the auxiliary circuit is set to turn on in advance of the reference time by an interval of a discharging time period of the capacitor in a dead time period.

Abstract: An image forming apparatus including a first carriage having a print head independently movable in a main scanning direction, a second carriage having a print head movable with the first carriage, an encoder sheet, first and second home position reference units provided to the first and second carriages, a home position detector that detects the first and second home position reference units, and first and second position detectors provided to the first and second carriages, which detect positions of the first and second carriages by reading the encoder sheet. A control unit controls ejection of ink from the print head of the first carriage based on an output from the first position detector, and ejection of ink from the print head of the second carriage based on the output from the second position detector.

Abstract: Four energization switching devices and positive/negative switching devices are controlled to form a path charging a positive capacitor; a path connecting a power supply with the positive capacitor in series and energizing an inductor to charge a control terminal of a target switching device; a path charging the control terminal using electromagnetism in the inductor; a path supplying circulating current to the power supply when potential of the control terminal becomes higher than voltage of the power supply; a path charging a negative capacitor; a path connecting the power supply with the negative capacitor in series and energizing the inductor to discharge the control terminal; a path discharging the control terminal using electromagnetism in the inductor; and a path supplying circulating current to the power supply when potential of the control terminal becomes lower than potential of a negative terminal of the power supply.

Abstract: A drive circuit for a semiconductor switching element is disclosed. The drive circuit includes a power supply, a capacitor, a connection changeover unit for switching a connection form between the power supply and the capacitor, a resistor connected to a control terminal of the semiconductor switching element, first and second switching elements whose common connection point is connected to the resistor, a positive-side diode whose cathode is connected to the first switching element, a negative-side diode whose anode is connected to the second switching element, and a current conduction control circuit for controlling the connection changeover unit, and the first and second switching elements to form (i) a first path for charging the capacitor, (ii) a second path for charging the control terminal of the semiconductor switching element, and (iii) a third path for discharging the control terminal of the semiconductor switching element.

Abstract: A zoom lens system comprises, from an object side to an image side: a first lens unit; a second lens unit; a third lens unit; a fourth lens unit; and a fifth lens unit having positive refractive power, wherein: in zooming from a wide angle end to a telephoto end, the first, the second, the third, and the fourth lens units move so that an interval between the first and the second lens units is larger at the telephoto end than that at the wide angle end, an interval between the second and the third lens units is smaller at the telephoto end than that at the wide angle end, and a distance between the third and the fourth lens units varies; and a focal length of the first lens unit, and focal lengths of an entire system at the wide angle end and the telephoto end are appropriately set.

Abstract: A recording device including a paper feeder tray that accommodated a recording medium, a print head that discharges ink on the recording medium to record an image thereon, a transfer roller that transfers the recording medium and a printed test chart on which multiple marks are arranged, a control device that controls the transfer roller, a first detection device that detects a rotation position of the transfer roller, a second detection device that detects the multiple marks arranged on the printed test chart, and a transfer device that transfers the recording medium from the paper feeder tray to the second detection device, wherein the control device obtains an difference between an actual transfer amount of each of the multiple marks obtained by detecting the multiple marks by the second detection device and a predetermined theoretical transfer amount of each of the multiple marks relating to a rotation position of the transfer roller, calculates a correction amount for the rotation amount of the transfer

Abstract: An air-coupled ultrasonic sensor capable of changing setting of an output sound pressure or an ultrasonic wave propagation distance depending on a use application, an installation site, or the like, with a simple structure. An air-coupled ultrasonic sensor includes: a closed-end cylindrical case including an opening portion at one end in its axial direction and a bottom surface at another end; a piezoelectric oscillator firmly fixed onto an inner bottom surface of the closed-end cylindrical case; an open-end cylindrical case including opening portions at both ends in its axial direction; and a thin film firmly fixed on one of the opening portions at one end of the open-end cylindrical case. The open-end cylindrical case is fitted to the closed-end cylindrical case, and includes a structure capable of moving along a side wall of the closed-end cylindrical case.

Abstract: A recording device including a carriage head, a recording head installed onto the carriage head, the recording head having an array of nozzles that discharges ink on a recording medium, a transfer roller that transfers the recording medium in a direction along the array of nozzles, a control device that controls rotation of the transfer roller, a first detection roller that detects a rotation position of the transfer roller, and a second detection device that detects a mark printed on the recording medium by the recording head, the control device including a print control device that controls printing the marks on the recording medium in the direction along the array of nozzles from the array of nozzles of the recording head while the carriage and the transfer roller remain still, a calculation device that calculates a correction amount for use in correction of a rotation angle of the transfer roller according to a difference between an actual transfer amount of the recording medium by the transfer roller at

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, and a rear lens unit including one or more lens units. An interval between respective adjacent lens units varies during zooming such that an interval between the first lens unit and the second lens unit is larger at a telephoto end than at a wide-angle end and an interval between the second lens unit and the third lens unit is smaller at the telephoto end than at the wide-angle end. The third lens unit includes at least one negative lens. An Abbe number (?d3n) and a relative partial dispersion (?gF3n) of a material of the negative lens are appropriately set based on predetermined conditional expressions.

Abstract: A zoom lens system comprises, from an object side to an image side: a first lens unit; a second lens unit; a third lens unit; a fourth lens unit; and a fifth lens unit having positive refractive power, wherein: in zooming from a wide angle end to a telephoto end, the first, the second, the third, and the fourth lens units move so that an interval between the first and the second lens units is larger at the telephoto end than that at the wide angle end, an interval between the second and the third lens units is smaller at the telephoto end than that at the wide angle end, and a distance between the third and the fourth lens units varies; and a focal length of the first lens unit, and focal lengths of an entire system at the wide angle end and the telephoto end are appropriately set.

Abstract: A zoom lens system comprises, from an object side to an image side: a first lens unit; a second lens unit; a third lens unit; a fourth lens unit; and a fifth lens unit having positive refractive power, wherein: in zooming from a wide angle end to a telephoto end, the first, the second, the third, and the fourth lens units move so that an interval between the first and the second lens units is larger at the telephoto end than that at the wide angle end, an interval between the second and the third lens units is smaller at the telephoto end than that at the wide angle end, and a distance between the third and the fourth lens units varies; and a focal length of the first lens unit, and focal lengths of an entire system at the wide angle end and the telephoto end are appropriately set.

Abstract: An airborne ultrasonic sensor capable of obtaining an asymmetric directivity pattern in a predetermined direction with a simple structure. The airborne ultrasonic sensor includes: a case whose one end is open and another end is a closed surface, so as to have a hollow portion; and a piezoelectric element which is disposed on an inner side of the closed surface, the closed surface being a vibration surface, in which the case has a side surface at least partially provided with a region which is obtained by removing the side surface from an opening surface side. The closed surface has a circular, elliptical, oval, square, or rectangular shape.

Abstract: A power conversion apparatus includes main circuits, in which switching elements are connected in parallel with diodes, respectively. An auxiliary circuit, which is formed of a series-connected second switching element and a capacitor, is connected in parallel with the diode operating as a freewheeling diode. The switching element of the main circuit, which is opposite to the auxiliary circuit, is set to turn on at a reference time. The second switching element of the auxiliary circuit is set to turn on in advance of the reference time by an interval of a discharging time period of the capacitor in a dead time period.

Abstract: A plurality of the light emitting device array units are arranged along a main scan direction in a staggered manner. In a density transformation mode, a transformation pattern is used to transform image data for each matrix of n by n pixels. A rate of writing an image in a sub-scan direction is multiplied by m, and a pixel density of image data written on a photosensitive body is multiplied by (2B+1)/2 in the main scan direction, and multiplied by m(2B+1)/2 in the sub-scan direction. A transformation pattern which is selected according to a position along the main scan direction at which an image is written with respect to a position of each of the plurality of light emitting device array units is used to transform image data.

Abstract: A zoom lens includes positive, negative, positive, and positive lens units, and the second lens unit includes negative, negative, negative and positive lenses. The first and third lens units are fixed and the second and fourth lens units are moved in zooming. 0.01<|f2/?(fw*ft)|<0.35 and 0.070<D2/TL<0.105 are satisfied. fw and ft are focal lengths of an overall system at wide angle and telephoto ends, f2 is a focal length of the second lens unit, TL is a distance on an optical axis from a lens surface closest to an object plane to an image plane when a distance from a lens surface closest to the image plane to the image plane is aerially converted, and D2 is a distance on the optical axis from a lens surface closest to the object plane in the second lens unit to the lens surface closest to the image plane in the second lens unit.

Abstract: A drive circuit for a semiconductor switching element is disclosed. The drive circuit includes a power supply, a capacitor, a connection changeover unit for switching a connection form between the power supply and the capacitor, a resistor connected to a control terminal of the semiconductor switching element, first and second switching elements whose common connection point is connected to the resistor, a positive-side diode whose cathode is connected to the first switching element, a negative-side diode whose anode is connected to the second switching element, and a current conduction control circuit for controlling the connection changeover unit, and the first and second switching elements to form (i) a first path for charging the capacitor, (ii) a second path for charging the control terminal of the semiconductor switching element, and (iii) a third path for discharging the control terminal of the semiconductor switching element.

Abstract: One of first and second switching devices turns on to flow a current along a current path between a potential reference output terminal of a drive-target switching device and a control terminal of the drive-target switching device to turn on the drive-target switching device. Thereby, a voltage changes between the control terminal of the drive-target switching device and the potential reference output terminal of the drive-target switching device to turn off the one of the first and second switching devices being turned on. Thereby, a potential of the control terminal of the drive-target switching device is clamped.

Abstract: An airborne ultrasonic sensor is obtained in which a sensor body and a housing have an integrated structure, and which can reduce spurious waves which propagate through the housing to arrive at the sensor body. The sensor is provided with the sensor body that radiates ultrasonic waves into air and at the same time receives reflected waves from a reflection source which exists in the air, a transmission and reception device that drives the sensor body and at the same time obtains a distance to the reflection source or a propagation speed of sound based on the reflected waves, and the housing that has the sensor body fixedly secured thereto with an integrated structure. The housing has groove portions which are different in acoustic impedance from their surroundings. The groove portions are arranged obliquely regarding either one of a horizontal direction or a vertical direction of the sensor body.

Abstract: Four energization switching devices and positive/negative switching devices are controlled to form a path charging a positive capacitor; a path connecting a power supply with the positive capacitor in series and energizing an inductor to charge a control terminal of a target switching device; a path charging the control terminal using electromagnetism in the inductor; a path supplying circulating current to the power supply when potential of the control terminal becomes higher than voltage of the power supply; a path charging a negative capacitor; a path connecting the power supply with the negative capacitor in series and energizing the inductor to discharge the control terminal; a path discharging the control terminal using electromagnetism in the inductor; and a path supplying circulating current to the power supply when potential of the control terminal becomes lower than potential of a negative terminal of the power supply.

Abstract: An ultrasonic sensor of the present invention is attached to the back face of a bumper 4, and provided with a matching member 3 that is in intimate contact with the ultrasonic wave transmitting surface of the ultrasonic sensor and the opposing face of the bumper 4 and that has an acoustic impedance smaller than each of the impedances of the sensor and the bumper.