The present invention relates to a power transmission device, which includes: a worm shaft; a Janggu (slim waist drum)-shaped worm which is provided on the worm shaft, and has a diameter-reduced part whose outer diameter is increased toward both ends from a center thereof in an axial direction of the worm shaft, wherein the diameter-reduced part has spiral worm teeth formed thereon; a first transmission shaft disposed in parallel to the worm shaft at an interval; and a first transmission gear which is provided on the first transmission shaft, and includes first gear teeth having tooth shapes conjugated with the worm teeth of the Janggu-shaped worm and are continuously formed in a spiral shape on an outer circumferential surface thereof, thus to rotate by threadedly engaging with the worm teeth of the Janggu-shaped worm.

Disclosed is a device for moving a brake pedal. The device for moving a brake pedal according to the present embodiment comprises: a lead screw fixed to an input rod of the brake pedal and having a first screw thread formed on the outer circumferential surface thereof; a first anti-rotation unit that prevents rotation of the lead screw; an actuator that provides power; a rotator rotated by the actuator; and a nut that rotates together with the rotator and is provided to be slidably movable with respect to the rotator, and that has a second screw thread formed on the inner circumferential surface thereof for meshing with the first screw thread.

A gear transmission includes a first helical-cut gearwheel (1) and a second helical-cut gearwheel (2) engaged for transmitting torques in different directions. The first gearwheel (1) and the second gearwheel (2) each include corresponding ring-shaped thrust collars (4, 5), and corresponding thrust collars (4, 5) each form a race (8, 9, 10, 11) having an overlap region. A first race (8) and a second race (9) form an overlap region for traction torques, and a third race (10) and a fourth race (11) form an overlap region for overrun torques. Each overlap region includes a contact surface or a contact point (14, 15), and each contact point (14, 15) is situated on a contact circle diameter (16, 17). The contact surfaces or contact points (8, 9) for traction torques and the contact surfaces or contact points (10, 11) for overrun torques are radially offset.

A gear transmission includes a first helical-cut gearwheel (1) and a second helical-cut gearwheel (2) engaged for transmitting torques in different directions. The first gearwheel (1) and the second gearwheel (2) each include corresponding ring-shaped thrust collars (4, 5), and corresponding thrust collars (4, 5) each form a race (8, 9, 10, 11) having an overlap region. A first race (8) and a second race (9) form an overlap region for traction torques, and a third race (10) and a fourth race (11) form an overlap region for overrun torques. Each overlap region includes a contact surface or a contact point (14, 15), and each contact point (14, 15) is situated on a contact circle diameter (16, 17). The contact surfaces or contact points (8, 9) for traction torques and the contact surfaces or contact points (10, 11) for overrun torques are radially offset.

A vehicle drive device uses a parallel shaft gear reducer (30) in which a gear is composed of helical gear, as a speed reducer part (B) that decelerates and outputs a rotation of an electric motor part (A). In the vehicle drive device, of meshing parts of the gears formed in the speed reducer part (B), two gears form a meshing part in which the amount of misalignment that occurs between the tooth surfaces of the two gears meshing with each other is different during driving and during coasting of a vehicle. A first tooth surface (S1) meshing with a mating tooth surface during driving is subjected to tooth surface modification, and a second tooth surface (S2) meshing with a mating tooth surface during coasting is subjected to tooth surface modification of an amount different from an amount of the tooth surface modification to the first tooth surface (S1).

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing is operationally coupled to the shift actuator and a linear clutch actuator. The linear clutch actuator is a self-adjusting actuator, and the transmission includes a self-adjusting clutch.

A speed reduction mechanism and a motor equipped with the speed reduction mechanism are provided. A pinion gear is provided with one spiral engagement projected part, and a helical gear is provided with a plurality of engagement recessed parts with which the engagement projected part is engaged. The engagement projected part and the engagement recessed part are formed so that their cross-sectional shapes along a direction orthogonal to an axial direction of the pinion gear are in arc shapes. A shape of helical teeth and a shape of the engagement recessed part are determined based on a shape of the engagement projected part provided on a spiral tooth.

A speed reduction mechanism and a motor equipped with the speed reduction mechanism are provided. A pinion gear is provided with one spiral engagement projected part, and a helical gear is provided with a plurality of engagement recessed parts with which the engagement projected part is engaged. The engagement projected part and the engagement recessed part are formed so that their cross-sectional shapes along a direction orthogonal to an axial direction of the pinion gear are in arc shapes. A shape of helical teeth and a shape of the engagement recessed part are determined based on a shape of the engagement projected part provided on a spiral tooth.

Motor driven systems with optimized performance and efficiency are provided. A drive system includes a motor and a gear system coupled with the motor by a shaft. The gear system includes a pair of input gears disposed on the shaft, and a pair of transfer shafts including transfer gears meshing with the input gears. The gear system is configured to cancel axial, radial and/or tangential forces for minimized net force at the shaft.

The geared motor and pointer display device are provided with a stopper mechanism which restricts the range of movement of the trailing-side gear when the trailing-side gear rotates in a counter-clockwise direction. Of the stopper touching part and the part touched by the stopper that together constitute the stopper mechanism, the stopper touching part comprises the end of a gear-side protrusion which is integrally formed with the middle part at the outer peripheral surface of the middle part of the trailing-side gear. As a consequence, the stopper touching part comes into contact with the part touched by the stopper at a position close to the central axis of rotation of the trailing side gear. Therefore, when the stopper mechanism is activated, the collision energy to which the trailing side cog is subjected is minimal, which makes it possible to suppress the rebound of the trailing side gear.