Abstract: A hoist (1) that is provided with a regenerative resistor (11) and contains the following in a casing (2, 3, and 20): a load-raising/lowering motor (7) driven by an inverter control device (12) and provided with a forced-cooling means (19); and a mechanism part (9) containing a reduction mechanism part (8) and a load sheave (10) that uses power from the reduction mechanism part (8) to take up and let out a chain. The load-raising/lowering motor (7), mechanism part (9), inverter control device (12), and regenerative resistor (11) are distributed inside the casing (2, 3, and 20) so as to achieve a balance of weight about the center of gravity (O) of the load applied when raising or lowering. Also, the inverter control device (12) and the regenerative resistor (11) are affixed to the casing (2, 3, and 20), in close contact therewith, in parts of the casing separated from each other with the mechanism part (9) therebetween.

Abstract: Disclosed is a motor in which a commutator (10) is provided with connecting wires which short-circuit equipotential segments; brushes (21) are constituted by a low-speed brush (21a), a high-speed brush (21b), and a common brush (21c) used in common by the low-speed and high-speed brushes, and are juxtaposed along the circumferential direction. The circumferential brush width (W2) of the high-speed brush is set to be smaller than the circumferential brush width (W1) of the low-speed brush. The high-speed brush and the low-speed brush are formed so that simultaneous sliding contact with equipotential segments (15) can be avoided. Additionally, armature cores (8) are provided such that a plurality of teeth (12) is point-symmetrical about a rotary shaft (3) at equal intervals in the circumferential direction, and the teeth and slots (13) are formed so as to exist alternately at intervals of 90 degrees in the circumferential direction.

Abstract: A clutch actuating apparatus for a double clutch transmission, may include an electric unit that generates rotational force, a decelerating unit coupled to the electric unit and reducing the rotational force of the electric unit, a straight-converting unit that converts the rotational force reduced by the decelerating unit into a straight motion force, a push rod that is moved straight by the straight motion force of the straight-converting unit and makes an operational stroke to selectively engage a clutch, a supplement force supplying unit engaging with the push rod to increase the straight movement force to the push rod or to remove the increased straight movement force from the push rod when the push rod engages or disengages the clutch, and a rod locating unit coupled to the push rod and changing a relative position of the push rod to the straight-converting unit.

Abstract: The invention relates to devices including rotary units and rotary mechanisms that are suitable for use in numerous applications. Rotary units typically include rotational components that are configured to rotate. In some embodiments, for example, multiple rotary units are assembled in rotary mechanisms such that neighboring pairs of rotational components counter-rotate or contra-rotate relative to one another during operation of the rotary mechanisms. Rotational components generally include one or more implements that are structured to perform or effect one or more types of work as the rotational components rotate relative to one another in a given rotary mechanism. In certain embodiments, implements are configured to rotate and/or to effect the movement of other components as rotational components rotate.

Abstract: A tubular electric motor unit (10) for roll-up elements, such as blinds, curtains or similar items. It is the type intended to be housed inside a tube (11) for winding the roll-up element. The unit (10) has a tubular body (12) inside which is housed a geared motor (13) with its drive output at one end of the tubular body and a limit stop unit (14) at the other end. To transmit the rotation to the limit stop unit there is a first transmission ring (15) that is fitted so it can be rotated on a protruding portion of the limit stop unit to couple kinetically with the limit stop unit and that has an external peripheral surface intended to couple peripherally with minimal clearance with the inside surface of a tube for winding the roll-up element.

Abstract: A brush holder is placed between a yoke housing and a gear housing and includes a holder member and a base member. The holder member is installed to an opening of the yoke housing and holds a plurality of brushes. The base member is installed to the holder member and includes a connector configured to connect with an external connector to receive an electric power. An output side end part of the yoke housing has a flange portion, through which the gear housing is fixed to the yoke housing. The holder member includes a contact portion that contacts an opening end portion of the yoke housing in an axial direction of a rotatable shaft. The contact portion is axially spaced from the base member by an axial gap.

Abstract: An electric actuation system for an emergency power system of an aircraft includes a motor control portion, a motor brake, a motor in electrical communication with the motor control portion, mechanical gearing in mechanical communication with the motor, the mechanical gearing configured to translate rotational motion of the motor into linear motion across at least one axis, and an extension member in mechanical communication with the mechanical gearing, the extension member configured to linearly travel across the at least one axis.

Abstract: A motor assembly comprises a gearbox (1), a motor (2) and a bushing assembly. The motor has a motor shaft (22), a worm is fixed to or formed on a worm portion of the motor shaft, which is located in the gearbox. The worm potion of a motor shaft is supported by a bushing assembly. The bushing assembly comprises a sleeve (4) and a bushing (3) fixed inside the sleeve. The bushing comprises a plurality of axial ribs (31) arranged around its outer surface. The sleeve comprises a plurality of grooves (41) in its inner surface which engage the ribs on the bushing. The sleeve also comprises a plurality of ribs around its outer peripheral surface which engage with the gearbox. The motor shaft is strengthened by the bushing assembly, and a self-locking ability of motor assembly is improved.

Abstract: A motor vehicle drive unit and an automotive vehicle comprising such a motor vehicle drive unit are provided. An electric motor has a rotor and a main stator rotatably mounted to a support structure. A first transmission provides an output to a first wheel axle shaft from the rotor. A second transmission provides an output to a second wheel axle shaft from the main stator. An auxiliary stator at least partially surrounds the main stator and is held stationary relative to the main rotatably mounted stator. A control unit is provided for controlling the auxiliary stator to add or subtract power to the main rotatably mounted stator.

Abstract: A wiper motor (10) comprises: a motor body (11) comprising a motor case (13) rotatably supporting an end of the motor shaft (17) in the axial direction thereof; a reduction mechanism (26) reducting the speed of rotation of the motor shaft (17) and transmitting the rotation having the reduced speed to a worm wheel (35); and a motion conversion mechanism (29) converting the rotational motion of the worm wheel (35) into a rocking motion and transmitting the rocking motion to an output shaft (28). The position of the output shaft (28) is set up that the axis (C1) of the output shaft (28) is closer to the motor case (13) than the axis (C2) of the worm wheel (35) and farther from the axis (C2) of the worm wheel (35) than the axis (C) of the motor shaft (17).

Abstract: An electrical machine includes a stationary secondary part which is self-excited or externally excited, a stationary primary part with a primary winding element, and a rotatably mounted magnetic modulator, which modulates a magnetic flux density. The magnetic modulator is arranged between the secondary part and the primary part or the primary part is arranged between the secondary part and the magnetic modulator.

Abstract: What is disclosed is a motor/transmission unit for a bicycle which is directly fastened or flange-mounted to a bottom bracket housing, in particular a standard bottom bracket housing. The standard bottom bracket housing is arranged between the motor/transmission unit and a chain ring. A part—in particular casing—of the motor/transmission unit which is integrally connected to the frame may be fastened or flange-mounted to the standard bottom bracket housing in accordance with the International Standard Chain Guide Mount (ISCG).

Abstract: A wiper motor of the present invention comprises: a reduction mechanism (26) for reducing the speed of rotation of the motor shaft (17) and transmitting the rotation to a worm wheel (35) and a motion conversion mechanism (29) for converting the rotary motion of the worm wheel (35) into a rocking motion and outputting the rocking motion to an output shaft (28). The reduction mechanism (26) is contained in the reduction mechanism containing chamber (27) of a gear frame (21), and the motion conversion mechanism (29) is contained in the motion conversion mechanism containing chamber (30) of the gear frame (21). A support surface (37) set up flush with the other end surface (35b) of the worm wheel (35) in the axial direction rotatably contained in the reduction mechanism containing chamber (27) is formed on the inner surface of the bottom wall (30a) of the motion conversion mechanism containing chamber (30).

Abstract: A starter comprises an electric motor which drives a rotor shaft, a drive shaft that can be rotationally coupled to the rotor shaft, and a pinion mounted on the drive shaft and movable in a translational movement between a rest position and an active position by a movement system. The starter comprises a coupling system that couples a rotary movement in one direction of rotation of the rotor shaft to the pinion. The coupling system moves from an uncoupled state into a coupled state and vice versa. In the coupled state, the rotor shaft is firmly attached to the pinion in the starting direction of rotation. In the uncoupled state, the pinion is disconnected from the rotor shaft in both directions of rotation. The starter further comprises a movement system for moving the pinion from the coupling system into the uncoupled state as it moves the pinion into active position.

Abstract: An electric actuator includes a direct current (DC) motor, a deceleration mechanism having an input gear, an intermediate gear, an output gear, and an output shaft, and a return mechanism. The return mechanism includes a first resilient member and a second resilient member. The first resilient member is configured to apply resilient force, which urges a movable body in a direction to return the movable body from its displacement position to initial position, to the output shaft or the output gear. The second resilient member is configured to apply resilient force, which urges the movable body in the direction to return the movable body from its displacement position to initial position, to a motor shaft, the input gear, or the intermediate gear.

Abstract: A generator arrangement is provided in which the functionality of two typically separate electrical power generators are combined together into a single generator that forms part of a three-in-one combined multi-generator which has a dual drive path with a shear section that immunizes one of the generators (e.g., the permanent magnet generator) within the single combined multi-generator from a failure of another generator (e.g., the main generator) within the single combined multi-generator.

Abstract: A method for forming an electromechanical actuator that involves using at least one motor module engageable with an output ram for controllably translating the output ram along a linear axis of the output ram. A torque sensing adaptive control (TSAC) system is used for monitoring motor module torque within the motor module and generating a disengagement command signal. The disengagement command signal is used to initiate disengagement of the motor module from the output ram when the torque within the motor module is outside an allowable motor module torque range.

Abstract: A cutaway portion is provided in a driving force transmission path and serves as a disconnection mechanism for disconnecting the driving force transmission path under the action of a torque of a predetermined magnitude or more, the driving force transmission path being a path through which a driving force is transmitted from an output shaft to a pinion. A partitioning portion is provided inside the body and disposed between the cutaway portion and a speed reduction portion so as to partition an area between the cutaway portion and the speed reduction portion.

Abstract: The invention provides a drive assembly for a telescoping wand of water jet device. The drive assembly includes an internally engaged rotary disk. With rotation of the internally engaged rotary disk, the telescoping wand of the water jet device is caused to retract or expand.

Abstract: A bearing is positioned relative to a rotatable shaft by inserting the bearing over the rotatable shaft until the bearing contacts a flange of the rotatable shaft, which is cold-forged on the rotatable shaft. The bearing is fixed to the rotatable shaft such that a swaged portion is formed in an outer peripheral portion of the rotatable shaft on an opposite axial side of the bearing, which is axially opposite from the flange, by swaging a corresponding part of the outer peripheral portion of the rotatable shaft such that the corresponding part of the outer peripheral portion of the rotatable shaft is radially outwardly bulged to form the swaged portion, and the swaged portion is axially pressed against the bearing to axially securely clamp the bearing between the swaged portion and the flange.

Abstract: An accessory system includes an accessory gearbox which includes a geartrain and a 2-Pole generator integrally mounted with the accessory gearbox such that a drive gear of the generator is in meshing engagement with the geartrain, containing a shear section, disconnect mechanism, and torsional compliance.

Abstract: A brush holder is placed between a yoke housing and a gear housing and includes a holder member and a base member. The holder member is installed to an opening of the yoke housing and holds a plurality of brushes. The base member is installed to the holder member and includes a connector, which is adapted to connect with an external connector to receive an electric power. An output side end part of the yoke housing has a flange portion, through which the gear housing is fixed to the yoke housing. The holder member includes a contact portion that contacts the flange portion of the yoke housing in an axial direction of a rotatable shaft.

Abstract: A food processor has a container, a working piece for processing food material in the container, and a motor assembly for driving the working piece. The motor assembly includes an electric motor and a speed reduction gear unit connected between the motor and the working piece. The speed reduction gear unit includes a damper for isolating the motor from vibrations from the working piece.

Abstract: Disclosed herein is a step motor, including a lead screw, a rotor fixed to an outer surface of the lead screw, a fixture containing a stator disposed to face the rotor and a housing whose one side end part is open to insert the stator and wrap the stator, and a bracket having a bracket body of a plate shape on which the housing is disposed and a bending part bent towards the one side end part of the housing from the bracket body.

Abstract: An unlocking actuator for automatic unlocking of vehicle seat and manual unlocking of vehicle seat. Rotary torque generated by an electric motor in order to unlock a vehicle seat is transmitted to a rotary gear which is thereby rotated. A substantially sectorial insertion hole is formed in a pulley along the rotational direction and an abutting surface is formed on one end side of the insertion hole. A first inner cable has one end fixed to a first groove for winding formed in the outer circumferential part of the pulley and wound in the first groove for winding, and the other end connected with an unlocking mechanism. A second inner cable has one end fitted idly in a second groove for winding formed in the outer circumferential part of the pulley and wound in the second groove for winding, and the other end connected with an unlocking operation rod.

Abstract: An electromechanical actuator for controlling the position of an aircraft component has a linear actuator to be driven to position a component. A transverse flux motor drives the linear actuator to move in a linear direction and control the position of the component.

Abstract: A system for converting marine surface wave energy into electric energy includes a barrier disposed generally vertically and having at least a portion thereof disposed above a surface of a body of water. The portion has a substantially planar surface disposed generally transverse to direction of marine surface waves. Bottom edge of the barrier is pivotally connected to one of a floor bed, a rigid formation and a rigid structure. At least one linear electric generator is coupled to storage of electric energy and is operable by a pivotal movement of the barrier. One type of electric generator is disposed external to the barrier while another type is mounted within a barrier chamber.

Abstract: A rotary electric machine includes: a stator having a stator winding and a stator core; a rotor having a first magnetic pole section and a second magnetic pole section, where the second magnetic pole section rotates respective to the first magnetic pole section; a shaft provided for the rotor; and a rotary mechanism configured to rotate the second magnetic pole section about the shaft. The rotary mechanism includes: a moving member configured to be movable along the shaft; a lead screw mechanism configured to move the moving member along the shaft; and a rotary member configured to rotate respective to the shaft along with the second magnetic pole section, where the rotary member engages the moving member and the second magnetic pole section.

Abstract: A geared motor assembly has a rotation-transmitting shaft for transferring output rotation of a reducer on the front side of a motor to an output shaft sensor on the rear side of the motor. A front end portion of the rotation-transmitting shaft is securely bonded to a rotation output member of the reducer by an adhesive that exhibits flexibility or elasticity after hardening, and a rear end portion of the rotation-transmitting shaft is rotatably supported by a sensor cover via a bearing in a position adjacent to the output shaft sensor. The rotation-transmitting shaft can be supported in a state free of axial runout by deformation of the adhesive and by the bearing. Consequently, the rotation angle position of the rotation output member can be detected with precision by the output shaft sensor in a position adjacent to the bearing.

Abstract: A hollow actuator with a built-in reduction gear includes a motor having an output shaft, and a reduction gear having an input shaft, the output shaft and the input shaft being provided separately from one another. The actuator also includes a motor section and a brake section disposed on a non-load side of the motor section. A bearing is attached to an inner periphery of the brake section. Another bearing that is different from the bearing provided on the inner periphery of the brake section rotatably supports the output shaft of the motor section.

Abstract: A gear motor assembly includes a gearbox, a motor mounted to the gearbox, a first damper and a second damper. The gearbox includes a gearing casing and a worm gear installed in the gear casing. The motor includes a stator and a rotor. The stator includes a housing. The rotor includes a motor shaft and a worm integrally rotating with the shaft. The shaft extends into the gear housing and the worm is meshed with the worm gear. The first damper is sandwiched between the gear casing and a first end of the shaft, eliminating end play between the shaft and the gear casing. The second damper is sandwiched between the motor housing and a second end of the shaft, eliminating end play between the shaft and the motor housing.

Abstract: A gear motor assembly includes a gearbox and a motor mounted to the gearbox. The gearbox includes a gear casing and a worm gear installed in the gear casing. The motor includes a stator, a rotor and brush gear. The rotor includes an shaft, a rotor core and a commutator fixed to the shaft. A worm integrally rotates with the shaft and is meshed with the worm gear. The brush gear includes multiple brushes slidably contacting the commutator, and multiple springs urging the corresponding brush towards the commutator. A lengthwise axis of the brush is inclined to a rotational axis of the commutator with a first angle between 75° to 87°.

Abstract: The invention relates to a drive device (1), in particular for window wiping devices in motor vehicles, having a motor housing (2) which is fixed to a gearbox housing (3) which has a housing upper side (7), and having an air-permeable diaphragm (14) which closes off an opening (15) which is provided in the gearbox housing (3), said diaphragm (14) having the purpose of equalizing pressure when fluctuations in temperature occur. The invention provides that the diaphragm (14) is arranged on a housing side section (16) which runs at an angle to a housing upper side (7). In addition, the invention relates to a motor vehicle having a mounted drive device (1).

Abstract: There is provided an electric power steering device, whereby it is possible to establish an electrical connection between an electric motor and a motor control unit with ease, and it is possible to suppress the electrically connecting portion of the electric motor and the motor control unit from influencing to assembling of any other part. A plate-shaped motor control unit electrically connected with an electric motor 10 is provided at a motor flange 10b of the electric motor, and in addition, a plate-shaped control unit side connection terminal electrically connected with a motor control unit 14 is provided at a motor mounting flange 6b of a housing 6 so as to be in face contact with a motor side connection terminal.

Abstract: An optical-device switching apparatus of a microscope includes a driving motor, and a rotation unit that is rotatably attached to a body and to which optical devices are attached, and a gear apparatus that is located between the driving motor and the rotation unit and transmits power from the driving motor to the rotation unit. The gear apparatus includes a backlash reduction system that reduces backlash.

Abstract: An electrical drive, especially for driving a windshield wiper system of a motor vehicle, comprises a worm gear having a worm shaft and a drive motor having a rotor. The rotor and the worm gear are arranged on axial sections of a shaft. The electrical drive furthermore comprises two shaft bearings on which the shaft is received, only one of said shaft bearings being arranged on the shaft in the vicinity of the rotor.

Abstract: A motor provided with a secondary driving system including: a casing; a dented wheel permanently rotating during the normal operation of the motor together with the rotor inside the casing; an endless screw that can be brought into a clutch engagement position in which the screw meshes with the dented wheel and in which the rotation of the screw drives the dented wheel in a non-reversible manner and that can be removed from said position in order to allow the normal operation of the motor; a driving member for manually rotating the endless screw, the driving member rotating about the same rotation axis as the endless screw and rotating the latter by direct engagement.

Abstract: A vehicle includes a transmission having an input member on a primary axis and a motor positioned on the primary or a secondary axis. The motor includes a rotor circumscribing a rotor shaft connected to the input member, a stator having axially-extending end-windings, and a reduction gear set. The gear set is positioned substantially within in a void or radial space between the end windings. The gear set may include a first member on the rotor shaft and a stationary second member positioned adjacent to the end windings. A method for assembling the motor includes providing the gear set, stator, and rotor, connecting the ring gear to the stationary member, and inserting the carrier member into the ring gear from an axial side of the traction motor until the gear set is substantially inside of the void between the end windings.

Abstract: A generator assembly for a wind power plant includes an annular stator, an annular rotor, and a spur gear transmission assembly. The generator assembly includes a basic carrier component on which all the bearings of the generator assembly are arranged.

Abstract: A transmission having a plurality of tilting balls and opposing input and output discs provides an infinite number of speed combinations over its transmission ratio range. The transmission provides multiple powerpaths and can be combined with electrical components to provide motor/generator functionality, which reduces the overall size and complexity of the motor and transmission compared to when they are constructed separately. In one embodiment, rotatable components of a continuously variable transmission are coupled separately to an electrical rotor and to an electrical stator so that the rotor and stator rotate simultaneously in opposite directions relative to one another. In other embodiments, an electrical rotor is configured to transfer torque to or from a disc that is in contact with a plurality of speed adjusters, while an electrical stator is configured to transfer torque to a shaft that is operationally coupled to the speed adjusters via an idler.

Abstract: This invention presents a highly efficient electric motor which can be embodied in several configurations, including a standard motor, a hub motor, a linear motor, or other motor configuration. As a regenerative device, the motor may also act as a part-time or full-time electrical generator. There is provided a motor composed of a stator and a rotor. The stator has an array of coils arranged therein. The rotor has an array of magnets arranged therein. Each of the coils includes a first winding of wire wrapped around a core, and the wire has a non-circular cross-section. The wire can be a flattened wire.

Abstract: The invention relates to a gear motor including a multiple-phase electric motor formed by a stator portion excited by electric coils and by a rotor having N pairs of poles radially magnetised in alternating directions, the stator portion including two angular sectors alpha-1 and alpha-2 with respective radii R1 and R2, and wide teeth and narrow teeth radially extending from an annular crown, characterized in that the wide teeth have a width higher than or equal to twice the width of the narrow teeth, in that the notch width is higher than the width of a narrow tooth, in that the angular sector alpha-1 is lower than 220° and includes all the coils, and in that the ratio R1/R2 ranges from 1.2 to 2.

Abstract: A brush DC motor with reduction mechanism includes: a brush DC motor including a motor case, a stator section and a rotor section having a substantially cylindrical core, the stator section and the rotor section being received in the motor case; and a first reducing section drivable by the motor. The first reducing section includes a first sun gear, an external ring gear positioned around the sun gear and several planetary gears held between the external ring gear and the sun gear and engaged with the sun gear and the external ring gear. The first reducing section further includes a planetary carrier for locating the planetary gears in their true positions. Multiple parallel linear splines are formed on a circumference of the core at intervals. One end of the core with the splines formed on the circumference of the end serves as the sun gear of the first reducing section.

Abstract: A high-torque motor device, comprising: a shaft, an electromagnetic unit with a stator and a rotor, and a single-stage planetary gear unit set onto the rotor. The single-stage planetary gear unit is provided with a planetary gear disk firmly sleeved onto the shaft, a plurality of planetary gears pivoted onto the planetary gear disk, an internal ring gear meshed with the planetary gear, and a sun gear fixed onto the rotor and meshed with the planetary gear. The present invention allows a single shaft between the motor and planetary gear unit, thus shortening the axial length of entire device and further guaranteeing the assembly precision of parts. This structure can be applied to motor and generator.

Abstract: The invention relates to a starter device (10) for cranking an internal combustion machine in a vehicle, having a pinion shaft (202) comprising a cranking pinion (22) at the front end and a pinion shaft (204) at the opposite end, slidingly guided and supported on a drive shaft (44) of the starter device (10) and received in a bearing by a bearing shell (210) of the starter device (10), characterized in that the cranking pinion (22) has a solid lubricant coating (216) at least in the area of the circumferential toothing (143).

Abstract: A drive train between a rotor and a transmission having a torque support for a wind turbine generator system, including a rotor shaft extending from the rotor and supported in this area by a first rotor shaft bearing and extending to the transmission for converting the rotor speed into a desired generator speed, wherein the rotor shaft is supported by a second rotor shaft bearing formed in the manner of a moment bearing which is arranged on the input side within the transmission in order to receive the partial rotor forces, moments and weight forces and to directly pass them on to the torque support.

Abstract: An electrical actuator comprising a housing of plastic with a reversible low voltage motor (2), electrical equipment for controlling and supplying the motor with power, where the electrical equipment (19,15) is enclosed in an enclosure (20) of fire resistant material. By this the housing (1) can be designed according to strength, hygiene and sealing, while fire prevention as a result of defect in the electrical equipment can be limited to the separate enclosure.

Abstract: A vehicle drive system includes a first electric motor having a first motor housing and a first motor shaft, a second electric motor having a second motor housing and a second motor shaft, and a gear system operatively connecting the first motor shaft and the second motor shaft. The gear system is configured and disposed to transmit torque from the first motor shaft to the second motor shaft to form a tandem electric motor drive system.

Abstract: An electric motor having a rotation shaft includes a motor housing into which the electric motor is accommodated, at least one pair of rolling bearings positioned in the motor housing and rotatably supporting both ends of the rotation shaft, and a displacement restriction member provided inside the motor housing and restricting a displacement of the rolling bearing in an axial direction of the rolling bearing. Each rolling bearing includes an inner race, an outer race, and rolling elements rotatably supported between the inner race and the outer race. The inner race is press fitted without any gaps onto an outer peripheral surface of the rotation shaft, and the outer race is press fitted without any gaps into a bearing attachment portion provided inside the motor housing.

Abstract: A motor 10 with reduction gear mechanism has a first worm 15 and a second worm 15? having mutually opposite screw torsion directions; a first counter gear 30 including a first large-diameter gear 31 meshing with the first worm 15 and a first small-diameter gear 35 rotating as one piece with the first large-diameter gear 31; a second counter gear 30? including a second large-diameter gear 31? meshing with the second worm 15? and a second small-diameter gear 35? rotating as one piece with the second large-diameter gear 31?; and an output gear 40 meshing with both the small-diameter gears 35, 35?; wherein a first device 50 for applying a force to press the first counter gear 30 towards a gear case 21 is arranged between the tip of the first small-diameter gear 35 and a gear case cover 29, and a second device 50? for applying a force to press the second counter gear 30? towards the gear case 21 is arranged between the tip of the second small-diameter gear 35? and the gear case cover 29.