An indicator instrument for a vehicle includes a rotational indicator that indicates a vehicle state parameter, and a stepper motor that rotates the rotational indicator. The stepper motor includes an output gear, a reduction mechanism, a motor casing housing the output gear and the reduction mechanism. The output gear includes an output shaft rotatable together with the rotational indicator, and a last-stage gear extending radially outward from the output shaft. The reduction mechanism includes a reduction gear engaged with the last-stage gear. The rotational indicator includes a rotational shaft press-fitted to a specified portion of the output shaft in the motor casing. The specified portion is displaced from the last-stage gear in an axial direction of the output shaft.

A two-phase bipolar step motor, comprises a rotor having a plurality of pairs of rotor poles of alternating magnetic polarity, and a stator having four primary energizable stator poles with conductive windings around those primary stator poles and four passive inter-poles located uniformly between every adjacent pair of primary stator poles, the passive inter-poles lacking any conductive windings. Both 18° steppers with five pairs of rotor poles and 30° steppers with three pairs of rotor poles are provided. Also provided are both PM hybrid mix steppers with 2D magnetic flux paths and hybrid steppers with 3D magnetic flux paths having an axial component. In each case, the overall lengths of the flux paths are substantially reduced from conventional designs resulting in improved motor efficiency.

A two-phase bipolar step motor, comprises a rotor having a plurality of pairs of rotor poles of alternating magnetic polarity, and a stator having four primary energizable stator poles with conductive windings around those primary stator poles and four passive inter-poles located uniformly between every adjacent pair of primary stator poles, the passive inter-poles lacking any conductive windings. Both 18° steppers with five pairs of rotor poles and 30° steppers with three pairs of rotor poles are provided. Also provided are both PM hybrid mix steppers with 2D magnetic flux paths and hybrid steppers with 3D magnetic flux paths having an axial component. In each case, the overall lengths of the flux paths are substantially reduced from conventional designs resulting in improved motor efficiency.

In a motor, a magnet is configured so that four pairs of S-poles and N-poles are formed at equal angular intervals, and a stator core has six salient poles formed thereon. Of the plurality of salient poles, when the first salient pole or the second salient pole faces a position between an S-pole and an N-pole, the other salient pole faces the center of an S-pole or the center of an N-pole. The radial-direction lengths of the first salient pole and the second salient pole among the plurality of salient poles are longer than the other salient poles, and the radial-direction length of the portion of the first coil wound around the first salient pole and the radial-direction length of the portion of the second coil wound around the second salient pole are longer than the radial-direction lengths of the other salient poles.

In a motor, a magnet is configured so that four pairs of S-poles and N-poles are formed at equal angular intervals, and a stator core has six salient poles formed thereon. Of the plurality of salient poles, when the first salient pole or the second salient pole faces a position between an S-pole and an N-pole, the other salient pole faces the center of an S-pole or the center of an N-pole. The radial-direction lengths of the first salient pole and the second salient pole among the plurality of salient poles are longer than the other salient poles, and the radial-direction length of the portion of the first coil wound around the first salient pole and the radial-direction length of the portion of the second coil wound around the second salient pole are longer than the radial-direction lengths of the other salient poles.

A torque delivering apparatus, including: polygonal cross-section stator body having a plurality of exterior side faces of even number extending between opposite axial end faces, the stator including cylindrical bore extending between the opposite axial ends and centred on central axis of the stator body; a rotor assembly having cylindrical cross-section sized for rotation within the cylindrical bore about the central axis with at least one permanent magnet and shaft coupled to the magnet for rotation; and a plurality of solenoid coils, each coil having plurality of windings and routed to have sections extending parallel along opposite ones of the plurality of exterior side faces; wherein each of the plurality of coils is configured to selectively receive current and generate magnetic field in the stator that is applied to the rotor magnet, the rotor being subject to magnetic torque within the cylindrical bore for rotating and aligning the magnetic field of the permanent magnet with the generated magnetic field.

A rotor includes a magnet yoke and a number of permanent magnets. The magnet yoke defines a number of accommodating slots therein, and each of the permanent magnets is received in one of the accommodating slots. An elastic member protrudes from the magnet yoke towards each of the accommodating slots, the permanent magnets are inserted in the corresponding accommodating slots, and the elastic members are bent and abut against the permanent magnets. A motor and a power tool include the rotor are also disclosed.

A rotor includes a magnet yoke and a number of permanent magnets. The magnet yoke defines a number of accommodating slots therein, and each of the permanent magnets is received in one of the accommodating slots. An elastic member protrudes from the magnet yoke towards each of the accommodating slots, the permanent magnets are inserted in the corresponding accommodating slots, and the elastic members are bent and abut against the permanent magnets. A motor and a power tool include the rotor are also disclosed.

A stepping motor includes a stator, and a rotor disposed in opposed relation to the stator and movable in a predetermined movement direction. The stator has a plurality of main poles, windings for the respective main poles, a plurality of stator teeth disposed on each of the main poles and spaced circumferentially from each other, and stator slots provided between respective adjacent pairs of the stator teeth. The rotor has a plurality of rotor teeth spaced from each other in the movement direction, and rotor slots provided between respective adjacent pairs of the rotor teeth. Slot magnets of hard magnetic inserts each magnetized in a slot depth direction are respectively provided in the stator slots and/or the rotor slots. The slot magnets each have a width that is 60% to 80% of the width of each of the slots as measured in the movement direction.

A stepping motor includes a stator, and a rotor disposed in opposed relation to the stator and movable in a predetermined movement direction. The stator has a plurality of main poles, windings for the respective main poles, a plurality of stator teeth disposed on each of the main poles and spaced circumferentially from each other, and stator slots provided between respective adjacent pairs of the stator teeth. The rotor has a plurality of rotor teeth spaced from each other in the movement direction, and rotor slots provided between respective adjacent pairs of the rotor teeth. Slot magnets of hard magnetic inserts each magnetized in a slot depth direction are respectively provided in the stator slots and/or the rotor slots. The slot magnets each have a width that is 60% to 80% of the width of each of the slots as measured in the movement direction.