Abstract: A rotor includes a hub, a rotor core, holes and permanent magnets. Salient poles are each formed between neighboring openings on a circumference of the rotor core and, when viewed from a front along a line of axis of the rotor, a recessed portion that is formed by causing one portion of an inner circumferential surface of the rotor core to bulge radially outward of another portion is provided in a region enclosed by a first virtual line connecting a center of the hub and a circumferential middle position on the circumference of a magnetic pole of the rotor core having permanent magnets provided therein and a second virtual line connecting the center of the hub and a circumferential middle position on the circumference of the salient pole adjacent to the magnetic pole at a leading side in a rotational direction of the rotor.

Abstract: A method for forming a loop winding having a plurality of meandering parts and disposed in a stator of a motor which includes: disposing the loop winding between a first die unit having a plurality of first dies and a second die unit having a plurality of second dies; and press forming the loop winding between the first dies and the second dies by relatively moving the first die unit and the second die unit toward each other, wherein the press forming step is so performed as to provide the loop winding with a plurality of meandering parts and, simultaneously, to reduce the loop winding in the radial direction.

Abstract: An electric vehicle employs an oil commonly used as a lubricating oil for gears and a coolant for a motor and is propelled by transmitting the rotational torque of the motor to wheels through the gears, the motor being partly immersed in the oil. It is determined whether the motor is in a state prior to being started or not. If it is judged that the motor is in the state prior to being started, coils of the motor are energized alternately with a first current supplied to the motor at an advanced angle for no torque to generate a magnetic flux, and a second current supplied to the motor at another advanced angle for no torque to generate a magnetic flux in a direction opposite to the magnetic flux generated by the first current, thereby heating the oil.

Abstract: A method for forming a loop winding having a plurality of meandering parts and disposed in a stator of a motor which includes: disposing the loop winding between a first die unit having a plurality of first dies and a second die unit having a plurality of second dies; and press forming the loop winding between the first dies and the second dies by relatively moving the first die unit and the second die unit toward each other, wherein the press forming step is so performed as to provide the loop winding with a plurality of meandering parts and, simultaneously, to reduce the loop winding in the radial direction.

Abstract: A forming machine for forming a loop winding having a plurality of meandering parts and disposed in a stator of a motor which includes: a first die unit having a plurality of first dies spaced from each other at regular intervals in a circumferential direction; and a second die unit having a plurality of second dies which are spaced from each other at the same intervals as the regular intervals in a circumferential direction and which are each disposed between adjacent ones of the first dies, wherein each of the second dies has a winding holding part for holding a loop winding; and the first die unit and the second die unit are each provided with a winding diameter reducing means for reducing the loop winding in the radial direction thereof according to a displacement of the first die unit in the axial direction relative to the loop winding held by the winding holding parts.

Abstract: A stator includes mutually independent annular coils and of two phases and teeth and of three phases.

Abstract: A claw-pole motor includes a rotor having permanent magnets; and a stator having stator rings assigned to three phases, which are coaxially stacked along the same axis. Winding attachment portions are formed between adjacent stator rings, and an annular winding is installed in each winding attachment portion for generating a magnetic field for rotating the rotor. Each stator ring has a main body and claw-shaped induction poles which protrude from the main body in radial directions. The claw-shaped induction poles of the three phases are serially arranged along a circumference of the stator rings and also face the permanent magnets. An interval between adjacent claw-shaped induction poles along the circumference of predetermined two of the stator rings of the three phases is smaller than an interval between adjacent claw-shaped induction poles along the circumference of any other pair of the stator rings.

Abstract: A forming machine for forming a loop winding having a plurality of meandering parts and disposed in a stator of a motor which includes: a first die unit having a plurality of first dies spaced from each other at regular intervals in a circumferential direction; and a second die unit having a plurality of second dies which are spaced from each other at the same intervals as the regular intervals in a circumferential direction and which are each disposed between adjacent ones of the first dies, wherein each of the second dies has a winding holding part for holding a loop winding; and the first die unit and the second die unit are each provided with a winding diameter reducing means for reducing the loop winding in the radial direction thereof according to a displacement of the first die unit in the axial direction relative to the loop winding held by the winding holding parts.

Abstract: A claw-pole motor includes a rotor having permanent magnets; and a stator having stator rings assigned to three phases, which are coaxially stacked along the same axis. Winding attachment portions are formed between adjacent stator rings, and an annular winding is installed in each winding attachment portion for generating a magnetic field for rotating the rotor. Each stator ring has a main body and claw-shaped induction poles which protrude from the main body in radial directions. The claw-shaped induction poles of the three phases are serially arranged along a circumference of the stator rings and also face the permanent magnets. An interval between adjacent claw-shaped induction poles along the circumference of predetermined two of the stator rings of the three phases is smaller than an interval between adjacent claw-shaped induction poles along the circumference of any other pair of the stator rings.

Abstract: A stator includes mutually independent annular coils and of two phases and teeth and of three phases.