Abstract: A generator motor includes a stator, a rotor that rotates relative to the stator, and a motor housing that houses the stator and the rotor. The motor housing includes a housing main body that encloses a periphery of the stator and the rotor and a cover that is attached to an end surface of the housing main body so as to cover an opening formed on the end surface, which is on an opposite side to an engine, of the housing main body. A drain hole for draining water inside the motor housing to below the motor housing is formed between a lower end of the cover and the end surface of the housing main body. The motor housing includes a covered section that covers the drain hole from below at a position that is lower than the drain hole.

Abstract: Provided is an electric motor capable of stabilizing a preload applied to a bearing by an annular spring and effectively retarding degradation of the annular spring. The electric motor includes a motor shaft, a rotor, a stator, a housing containing the rotor and the stator in a posture where the motor shaft extends vertically, an upper bearing and a lower bearing supporting the motor shaft, and an annular spring applying a downward preload to the upper bearing. The lower bearing is fixed to the motor shaft and the housing. The housing has a load-receiving surface receiving an upward thrust load overcoming the preload from the upper bearing.

Abstract: An electric motor to be easily assembled while taking the advantages of a retrofitted electric motor, excellent maintenance performance and no fear of damage in a temperature sensitive device due to resin injection pressure. The electric motor includes an electric motor shaft, a rotor, a stator, a housing, a sealing body formed of sealant to cover a coil end of the stator, a temperature sensitive device, an end cover, and a resilient retaining member. The electric motor shaft passes through the end cover. The sealing body includes a temperature-sensitive-device support surface opposed to the end cover. The temperature sensitive device is retained between the end cover and the temperature-sensitive-device support surface while the retaining member is interposed between the temperature sensitive device and the end cover.

Abstract: The axial lengths of coupling portions of a flywheel, a rotor shaft, and a pump shaft are reduced to reduce the axial length of an entire power unit. A crankshaft 4 and a flywheel 8 are directly coupled to each other and the flywheel 8 and a rotor shaft 5 are directly coupled to each other. A coupling 20 is directly coupled to an end face of the rotor shaft 5 on the opposite side to the flywheel 8. A pump shaft 6 is connected to the coupling 20. Coupling surfaces of the flywheel 8 and the rotor shaft 5 and coupling surfaces the rotor shaft 5 and the coupling 20 are arranged within a width range of a coil 19.

Abstract: Provided are, an electric motor assembly capable of preventing a sealant from leakage through a lead-wire drawing portion, and an electric motor manufacturing method with use of the electric motor assembly. The electric motor assembly includes a rotor (12), a stator (13), a casing (14), a partition wall (21) with through-holes (22), plugs (23) made of a highly elastic material and including a tapered outer peripheral surface to be fitted into the through-holes (22), and lead wires (25) connected to the stator (13). The plugs (23) surround lead-wire insertion holes (24). A sealant (20) is injected into the casing (14) in a state that the lead wires (25) are drawn through the lead-wire insertion holes (24).

Abstract: Provided is a motor including a rotor, a stator having a stator core and a coil, a stator frame, an end cover, first and second bearings, and a heat radiating resin in the stator frame. The coil includes first and second end portions projecting oppositely and axially. The stator frame includes a peripheral wall and an end wall, whose respective central parts form first and second boss portions holding the first and second bearings respectively. The heat radiating resin includes a first resin part covering the first end portion and closely contacting an inner surface of the stator frame, and a second resin part covering the second end portion and separating from an outer peripheral surface of the second boss portion. The first resin part has a portion between the first end portion and the first boss portion, the portion having a greater thickness than that of the other.

Abstract: A slewing-type working machine includes: a slewing motor which is a hydraulic motor for slewing; a variable-displacement hydraulic pump; a slewing operation device including an operation member; a control valve controlling the slewing motor based on an operation signal thereof; a pump regulator; a relief valve letting excess fluid to a tank; operation detectors detecting an operation direction and amount of the operation member; a motor rotational speed detector; and a controller controlling a discharge flow rate of the hydraulic pump. The controller obtains a deviation between a target rotational speed of the slewing motor obtained from a slewing operation amount and an actual rotational speed detected by the motor rotational speed detector, and controls the discharge flow rate to make the deviation closer to 0.

Abstract: The axial lengths of coupling portions of a flywheel, a rotor shaft, and a pump shaft are reduced to reduce the axial length of an entire power unit. A crankshaft and a flywheel are directly coupled to each other and the flywheel and a rotor shaft are directly coupled to each other. A coupling is directly coupled to an end face of the rotor shaft on the opposite side to the flywheel. A pump shaft is connected to the coupling. Coupling surfaces of the flywheel and the rotor shaft and coupling surfaces the rotor shaft and the coupling are arranged within a width range of a coil.