Noise caused by a gap between a rotor and a plate can be suppressed even when there are dimensional variations in members or assembly states. In a configuration of a stepping motor including front side and end side stator assemblies (200, 300), a rotor (400) provided with a rotor member (402) and a shaft (403) that are accommodated in the stator assemblies (200, 300), and a front plate (210) and an end plate (310) that are arranged on both sides of the stator assemblies (200, 300) in an axial direction, and are configured to couple the stator assemblies (200, 300), a projection (700) in an annular shape is provided on a surface of the front plate (210) facing the rotor member (402) to protrude toward the rotor member (402), a coil spring (800) that is interposed between the front plate (210) and the rotor member (402) is accommodated in the inner side of the projection (700), and the rotor (400) is urged toward the end plate (310) by the coil spring to be elastically pressed against the end plate (310).

An electric motor and associated systems and methods are described herein. A representative electric motor includes a stator having windings therein, wherein the stator has a diameter and a length greater than the diameter; and a rotor assembly inside the stator, wherein the rotor assembly includes a set of magnets configured to provide six or more poles.

A drive device includes a hollow hub rotatable about hub shafts extending parallel to a center axis, a motor housed in the hub and fixed to the hub shafts, and a speed reducer connected to the motor and the hub. The motor includes a rotor including a motor shaft extending parallel to the hub shafts, a stator disposed outside the rotor in a radial direction, and a motor housing holding the stator therein. The drive device includes thermal grease thermally connecting the hub and the motor housing to each other.

To provide a power tool configured to stably rotate an end tool. The provided power tool includes a brushless motor including a rotor configured to rotate; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsating voltage; an inverter circuit configured to perform switching operations to output the pulsating voltage to the brushless motor; a deceleration mechanism including: a driving portion at a rotor side, a driven portion configured to transmit a rotating force to an end tool side, and an elastic member configured to transmit a rotational force of the driving portion to the driven portion, the deceleration mechanism configured to decelerate a speed of a rotation of the rotor and configured to transmit the rotation to an end tool.

To provide a power tool configured to stably rotate an end tool. The provided power tool includes a brushless motor including a rotor configured to rotate; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsating voltage; an inverter circuit configured to perform switching operations to output the pulsating voltage to the brushless motor; a deceleration mechanism including: a driving portion at a rotor side, a driven portion configured to transmit a rotating force to an end tool side, and an elastic member configured to transmit a rotational force of the driving portion to the driven portion, the deceleration mechanism configured to decelerate a speed of a rotation of the rotor and configured to transmit the rotation to an end tool.

An electromagnetic actuator having a speed reducer has a stator and a rotor arranged to move rotationally relative to the stator. A drive gear is fixed to the rotor. At least three planetary gears are mounted on the stator and each of the at least three planetary gears are engaged by the drive gear. An annular gear is rotationally mounted on the first stator the annular gear is engaged by each of the at least three planetary gears.

To provide an outer rotor type motor capable of suppressing the runout of a top surface by improving the strength in a fitted part between a rotor yoke and a rotor shaft and suppressing resonance between vibration generated by rotation of a rotated body to be a load and motor vibration to thereby realize noise reduction. A rotor yoke is configured so that a rotor hub is fitted to a top surface portion formed in a cup shape integrally with a rotor shaft, and a reinforcing hub concentrically fixed to the rotor shaft with the rotor yoke is arranged so as to overlap the rotor hub.

To provide an outer rotor type motor capable of suppressing the runout of a top surface by improving the strength in a fitted part between a rotor yoke and a rotor shaft and suppressing resonance between vibration generated by rotation of a rotated body to be a load and motor vibration to thereby realize noise reduction. A rotor yoke is configured so that a rotor hub is fitted to a top surface portion formed in a cup shape integrally with a rotor shaft, and a reinforcing hub concentrically fixed to the rotor shaft with the rotor yoke is arranged so as to overlap the rotor hub.

A plate separator for separating a substance from a substance mixture, with a separator device and an electric motor for rotary driving of the separator device. The separator device is coupled to the electric motor in a rotationally fixed manner. The electric motor is configured as an external rotor and has an inner-lying stator and an outer-lying rotor in the radial direction with respect to an axis of rotation. The separator device is fastened to the rotor and extends outward from the rotor in the radial direction. The stator is arranged, as viewed in the axial direction with respect to the axis of rotation, at least partially overlapping with the separator device.

A plate separator for separating a substance from a substance mixture, with a separator device and an electric motor for rotary driving of the separator device. The separator device is coupled to the electric motor in a rotationally fixed manner. The electric motor is configured as an external rotor and has an inner-lying stator and an outer-lying rotor in the radial direction with respect to an axis of rotation. The separator device is fastened to the rotor and extends outward from the rotor in the radial direction. The stator is arranged, as viewed in the axial direction with respect to the axis of rotation, at least partially overlapping with the separator device.