Abstract: A drive unit includes: an inverter; an electric motor that has a first winding connected to an output part of the inverter and a second winding connected to the first winding; a first semiconductor switch that has a first end connected to the first winding and a second end connected to the second winding; a second semiconductor switch that has a first end and a second end connected to the first winding and the first semiconductor switch; and a snubber circuit that is provided between the second end of the first semiconductor switch and the first end of the second semiconductor switch and has a capacitor and a diode.

Abstract: A drive unit includes: an inverter; an electric motor that has a first winding connected to an output part of the inverter and a second winding connected to the first winding; a first semiconductor switch that has a first end connected to the first winding and a second end connected to the second winding; a second semiconductor switch that has a first end and a second end connected to the first winding and the first semiconductor switch; and a snubber circuit that is provided between the second end of the first semiconductor switch and the first end of the second semiconductor switch and has a capacitor and a diode.

Abstract: An inverter device includes a power supply unit and a switch controller. The power supply unit supplies AC power to an AC motor whose electric characteristics in response to a rotation speed are switchable between low speed characteristics and high speed characteristics. The switch controller switches the electric characteristics of the AC motor. The switch controller executes switching control that alternately switches the electric characteristics of the AC motor between the low speed characteristics and the high speed characteristics on the basis of the rotation speed of the AC motor.

Abstract: A winding switching signal generator is configured to obtain information indicating a degree of field weakening from at least one of a current command calculator and a constant output controller, and to generate a winding switching signal for switching from a low speed rotation state to a high speed rotation state when the degree of the field weakening exceeds a predetermined condition in the low speed rotation state.

Abstract: Provided is an inverter apparatus 20 configured to switch a current winding to an optimal winding when a rotation speed of a rotor of an AC electric motor 40 is within a hysteresis region defined by first and second switch timings for switching a state of an armature winding between a first winding and a second winding and when the current winding differs from the optimal winding.

Abstract: An inverter device includes a power supply unit and a switch controller. The power supply unit supplies AC power to an AC motor whose electric characteristics in response to a rotation speed are switchable between low speed characteristics and high speed characteristics. The switch controller switches the electric characteristics of the AC motor. The switch controller executes switching control that alternately switches the electric characteristics of the AC motor between the low speed characteristics and the high speed characteristics on the basis of the rotation speed of the AC motor.

Abstract: Provided is an inverter apparatus 20 configured to switch a current winding to an optimal winding when a rotation speed of a rotor of an AC electric motor 40 is within a hysteresis region defined by first and second switch timings for switching a state of an armature winding between a first winding and a second winding and when the current winding differs from the optimal winding.

Abstract: A winding switching signal generator is configured to obtain information indicating a degree of field weakening from at least one of a current command calculator and a constant output controller, and to generate a winding switching signal for switching from a low speed rotation state to a high speed rotation state when the degree of the field weakening exceeds a predetermined condition in the low speed rotation state.

Abstract: A wiring board includes a conductor plate including a wiring portion and an electrode portion connected to a power conversion semiconductor element, a liquid-cooling pipe mounted near the conductor plate and causing a cooling liquid to be supplied therethrough, and an insulating resin material arranged at least between the conductor plate and the liquid-cooling pipe.

Abstract: A wiring board includes a conductor plate including a wiring portion and an electrode portion connected to a power conversion semiconductor element, a liquid-cooling pipe mounted near the conductor plate and causing a cooling liquid to be supplied therethrough, and an insulating resin material arranged at least between the conductor plate and the liquid-cooling pipe.

Abstract: This power converter includes a power-conversion semiconductor element, an electrode conductor having a substantially flat upper end surface, and a sealant. The sealant allows the substantially flat upper end surface of the electrode conductor to be exposed at an upper surface of the sealant, and provides electrical connection with an external device at the upper end surface of the exposed electrode conductor.

Abstract: A winding switching apparatus includes a winding switching device and a drive circuit. The winding switching device is configured to switch a plurality of windings of an AC motor. The drive circuit is configured to control the winding switching device. The winding switching device includes a winding switch, a diode bridge, and a capacitor. The diode bridge includes a positive-side DC output terminal, a negative-side DC output terminal, and AC input terminals. The AC input terminals corresponds to respective phases of the AC motor. The positive-side and negative-side DC output terminals are respectively connected to positive-side and negative-side DC buses provided in an inverter. The AC input terminals are respectively connected to winding-switching terminals corresponding to the respective phases of the AC motor. The AC input terminals are respectively connected to phase terminals provided in the winding switch.

Abstract: A winding switching apparatus includes a winding switching device and a drive circuit. The winding switching device is configured to switch a plurality of windings of an AC motor. The drive circuit is configured to control the winding switching device. The winding switching device includes a winding switch, a diode bridge, and a capacitor. The diode bridge includes a positive-side DC output terminal, a negative-side DC output terminal, and AC input terminals. The AC input terminals corresponds to respective phases of the AC motor. The positive-side and negative-side DC output terminals are respectively connected to positive-side and negative-side DC buses provided in an inverter. The AC input terminals are respectively connected to winding-switching terminals corresponding to the respective phases of the AC motor. The AC input terminals are respectively connected to phase terminals provided in the winding switch.

Abstract: A winding switching apparatus for switching windings of an AC three-phase motor is provided. In each winding switching section of the winding switching apparatus, a positive-side charging resistor, a negative-side charging resistor, and a capacitor are connected in series between a positive-side DC bus and a negative-side DC bus of an inverter; the positive side of the capacitor is connected to the cathodes of respective diodes of a diode unit; and switching between high-speed windings and low-speed windings is carried out, with a capacitor potential being the same as an inverter DC bus voltage. A state detector and a comparator are also provided for each winding switching section to detect erroneous wiring and component abnormalities.

Abstract: A winding switching apparatus for switching windings of an AC three-phase motor is provided. In each winding switching section of the winding switching apparatus, a positive-side charging resistor, a negative-side charging resistor, and a capacitor are connected in series between a positive-side DC bus and a negative-side DC bus of an inverter; the positive side of the capacitor is connected to the cathodes of respective diodes of a diode unit; and switching between high-speed windings and low-speed windings is carried out, with a capacitor potential being the same as an inverter DC bus voltage. A state detector and a comparator are also provided for each winding switching section to detect erroneous wiring and component abnormalities.

Abstract: A binding member removing apparatus 300 comprises a tray 30 for mounting thereon a bundle D of document sheets bound with a staple S, a removing unit 410 for removing the staple S from the bundle D of document sheets mounted on the tray 30, and a moving unit for moving the staple S removed by the removing unit 410. The removing unit 410 is provided with an inserting member 411 to be passed between the bundle of document sheets and the binding member binding the bundle of document sheets and the inserting member 411 is provided with a plurality of elongated parts 412 formed in the shape of a comb having teeth extended in the direction of insertion thereof. The inserting member optionally comprises a first inserting member 811 to be passed between the obverse face of the bundle D of document sheets and the staple S and a second inserting member 812 to be passed between the reverse face of the bundle D of document sheets and the staple S as a binding member.

Abstract: A binding member removing apparatus 300 comprises a tray 30 for mounting thereon a bundle D of document sheets bound with a staple S, a removing unit 410 for removing the staple S from the bundle D of document sheets mounted on the tray 30, and a moving unit for moving the staple S removed by the removing unit 410. The removing unit 410 is provided with an inserting member 411 to be passed between the bundle of document sheets and the binding member binding the bundle of document sheets and the inserting member 411 is provided with a plurality of elongated parts 412 formed in the shape of a comb having teeth extended in the direction of insertion thereof. The inserting member optionally comprises a first inserting member 811 to be passed between the obverse face of the bundle D of document sheets and the staple S and a second inserting member 812 to be passed between the reverse face of the bundle D of document sheets and the staple S as a binding member.

Abstract: The present invention relates to a sheet conveying apparatus for conveying a sheet in recirculation. The apparatus comprises a feed tray, a feed mechanism, a recirculation conveying mechanism for conveying the sheet fed by the feed mechanism to return it to the feed tray. The recirculation conveying mechanism includes a discharge tray on which the plurality of sheets are temporally discharged and accumulated and a moving mechanism for moving the sheets accumulated on the discharge tray to the feed tray. The apparatus further comprises a feed sensor detecting whether or not any sheets present on the feed tray. The sheets discharged on the discharge tray are moved to the feed tray by the moving mechanism when all sheets on the feed tray are fed and the feed sensor detects none of the sheet.

Abstract: The preset invention relates to a sheet conveying apparatus equipped with a tray which couples feed port and discharge port to each other by a continuous surface. The tray comprises a first surface adjacent to the feed port for placing thereon sheets to be fed, a second surface adjacent to the discharge port for placing thereon discharged sheets, the second surface being tilted up so that the front end of the discharged sheet is positioned upper than the rear end thereof, and a bent portion at which the end of the first surface at the discharge side and the end of the second surface at the feed side are coupled to each other. A length of the first surface ranging from the bent portion to the feed port in the sheet conveyance direction is larger than one half of the length of a feedable maximum size sheet in the sheet conveyance direction.

Abstract: The present invention relates to a sheet conveying apparatus comprising a separating mechanism and a conveying mechanism. The separating mechanism separates a plurality of sheets to convey it one by one. The separating mechanism applies a friction force to the sheet to be conveyed in a direction opposite to the sheet conveying direction. The separating mechanism has a plurality of separating members disposed in a direction perpendicular to the sheet conveying direction. The conveying mechanism receives and conveys the sheet separated by the separating mechanism. The conveying mechanism has a plurality of conveying rollers disposed in a direction perpendicular to the sheet conveying direction. An outermost profile width of the conveying rollers in a direction perpendicular to the sheet conveying direction is smaller than that of the separating rollers.