Abstract: A rotary electric machine includes a stator in which windings are arranged around a plurality of main poles of a stator core, and a hybrid type rotor arranged with an air gap between the stator and the rotor has a step angle for the rotor of about 4.09° and uses metal bearings for supporting a rotor shaft of the rotor. Setting of the step angle for the rotor to be about 4.09° can make a rotation angle of the rotor caused by excitation of the windings by an input pulse signal larger as compared with a typical motor having a step angle of about 1.8°. With this unique arrangement, the rotor can be rotated at higher speeds, increasing the motor efficiency. Therefore, the motor output at approximately the same level as that of a conventional motor can be obtained without keeping the air gap high precision. Due to this, even if inexpensive slide bearings, i.e.

Abstract: A stepping motor drive circuit includes a control-purpose controller including a control-purpose position detecting unit; a rotation command information inputting unit arranged to receive command information on the rotating position of the stepping motor; a control-purpose deviation calculating unit arranged to calculate a positional deviation between the rotating position of the stepping motor detected by the control-purpose position detecting unit and the rotating position included in the command information; and an amplitude value setting unit. The amplitude value setting unit switches operations of stator coils of the stepping motor pursuant to the command information, rotate the stepping motor to the rotating position included in the command information, and increase or decrease an amplitude value of a drive current fed to the stator coils during stoppage of the stepping motor depending on the positional deviation calculated by the control-purpose deviation calculating unit.

Abstract: An impeller includes a substantially cylindrical cup portion arranged to rotate about a center axis, a plurality of blades fixed to an outer circumferential surface of the cup portion for unitary rotation with the cup portion to draw air from one axial side and discharge the air to the other axial side, and an annular connector portion arranged to interconnect the blades. The connector portion has a substantially cylindrical shape in a position spaced apart about 70% to about 90% of the radial length of the blades from the base of each of the blades on the outer circumferential surface of the cup portion, and the ratio of a total axial height of the connector portion to a total radial gap between the outer circumferential surface of the cup portion and the inner circumferential surface of the connector portion is equal to or smaller than about 0.9.

Abstract: A rotary electric machine includes a stator in which windings are arranged around a plurality of main poles of a stator core, and a hybrid type rotor arranged with an air gap between the stator and the rotor has a step angle for the rotor of about 4.09° and uses metal bearings for supporting a rotor shaft of the rotor. Setting of the step angle for the rotor to be about 4.09° can make a rotation angle of the rotor caused by excitation of the windings by an input pulse signal larger as compared with a typical motor having a step angle of about 1.8°. With this unique arrangement, the rotor can be rotated at higher speeds, increasing the motor efficiency. Therefore, the motor output at approximately the same level as that of a conventional motor can be obtained without keeping the air gap high precision. Due to this, even if inexpensive slide bearings, i.e.

Abstract: A motor includes a cylindrical or substantially cylindrical rotor unit configured to rotate about a rotation axis; a bearing unit arranged to rotatably support the rotor unit; a bearing holder arranged to hold the bearing unit; a disc-shaped or substantially disc-shaped base to which the bearing holder is fixed; a stator unit arranged inside the rotor unit and fixed to the bearing holder; and a circuit board arranged between the base and the stator unit and held by the stator unit. The circuit board is supported on the base through an insulative and flame-retardant vibration-preventing member.

Abstract: A drum rotating device enables a drum and a driving device mounted in the drum to be supported with a simple structure and which reduces the possibility that the driving shaft of the driving device may be offset with respect to the rotation axis of the drum. The drum rotation device includes the drum and the driving device arranged to drive and rotate the drum. The drum includes an outer cylinder, an inner cylinder arranged inside the outer cylinder coaxially therewith, and a support wall arranged to connect the outer and inner cylinders to each other at an approximately intermediate portion in the axial direction. The outer and inner cylinders are substantially cylindrical. The driving device is fixed to a frame at one axial end. The driving shaft of the driving device extends through the drum and is rotatably supported by the frame through a bearing at the other axial end.

Abstract: A rotary electric machine includes a stator in which windings are arranged around a plurality of main poles of a stator core, and a hybrid type rotor arranged with an air gap between the stator and the rotor has a step angle for the rotor of about 4.09° and uses metal bearings for supporting a rotor shaft of the rotor. Setting of the step angle for the rotor to be about 4.09° can make a rotation angle of the rotor caused by excitation of the windings by an input pulse signal larger as compared with a typical motor having a step angle of about 1.8°. With this unique arrangement, the rotor can be rotated at higher speeds, increasing the motor efficiency. Therefore, the motor output at approximately the same level as that of a conventional motor can be obtained without keeping the air gap high precision. Due to this, even if inexpensive slide bearings, i.e.

Abstract: A contactless potentiometer includes a shaft and a magnet rotatable together with the shaft and detects a rotational angle of the shaft corresponding to a change in magnetic fields caused by the rotation of the magnet, the magnet being held in a tip end portion of the shaft. The potentiometer includes a cover member attached to a housing at a tip end side of the shaft and arranged to define a closed sensor area between the cover member and the housing, and a circuit board mounted to the cover member at a side of the sensor area in a perpendicular or substantially perpendicular relationship with the shaft. The cover member includes a recess portion arranged on a surface of the cover member facing the circuit board, the recess portion cooperating with the circuit board to define a component-mounting spare space.

Abstract: A motor driving system that changes a rotation speed of a motor pursuant to a speed command includes a main device including a drive circuit configured to drive the motor, an input device configured to input the speed command to the drive circuit, and a signal insulating unit configured to insulate the input device from the main device and to transmit the speed command from the input device to the drive circuit of the main device.

Abstract: A rotary electric machine includes a rotor, a stator, a circuit substrate, a tubular closed-top and closed-bottom motor case arranged to accommodate the rotor, and bearings. The motor case is axially divided into a first casing and a second casing. Each of a first and a second tap portion of the first and the second casings includes an inner circumferential surface and at least one groove arranged on the inner circumferential surface. A lead bush includes a through-hole arranged to guide a lead wire and at least three annular bulging portions arranged at a specified interval along an outer circumferential surface of the lead bush. A middle annular bulging portion of the three annular bulging portions is fitted to the groove of each of the first tap portion and the second tap portion so that the lead bush is gripped between the first tap portion and the second tap portion.

Abstract: A magnetic circuit suitable for a self-held type rotary solenoid while maintaining properties, reducing cost, e.g., a material cost, and making the rotary solenoid smaller in size is provided. The rotary solenoid includes a swing yoke to which two magnets are fixed and a fixed yoke including projection portions at opposite sides thereof. An electromagnetic coil including a major magnetic pole is arranged at a center of the fixed yoke. The rotary solenoid is arranged to define a magnetic circuit extending through one of the magnets, the major magnetic pole, the fixed yoke, the projection portion, and the other magnet at a shortest distance. Therefore, even if a magnet made of a material having a low grade is used, it is possible to maintain sufficient magnetic properties.

Abstract: A hybrid rotary electrical machine that obtains a deviation angle of about one half of a pole teeth pitch between magnetic teeth of two rotor magnetic pole members gripping a permanent magnet of a rotor including rotor magnetic pole members that include the magnetic teeth at an equal pitch T on a surface thereof. The rotor magnetic pole members include cutout portions on the inner circumferential surface or the outer circumferential surface of the rotor magnetic pole members in a specified positional relationship with respect to the magnetic teeth. The cutout portions of one of the rotor magnetic pole members are axially aligned with the cutout portions of the other rotor magnetic pole member turned upside down so the magnetic teeth of one of the rotor magnetic pole members have a phase difference of about T/2 with respect to the magnetic teeth of the other rotor magnetic pole member.

Abstract: A brushless DC motor including a rotor capable of minimizing demagnetization of a magnet even when a short-circuit brake operation is performed by short-circuiting motor coils includes two kinds magnets differing in coercive force from each other which are alternately arranged into an annular shape along a circumferential direction. A magnet having a high coercive force is arranged in the portion where a diamagnetic flux is strongly generated. The portion where a diamagnetic flux is generated is the salient pole portion of a stator. A counter electromotive force becomes greatest when the center of the salient pole portion of the stator comes closer to the border of an N-pole and an S-pole of the magnet. Since the diamagnetic flux has a maximum value in that position, the magnet having a high coercive force is arranged near the border of an N-pole and an S-pole.

Abstract: A slip ring device includes a hollow pipe-shaped shaft rotatably supported inside a tubular body of a main case through a bearing and an electricity-collecting body integrally and concentrically provided in the shaft. The electricity-collecting body preferably includes a plurality of electricity-collecting rings and a plurality of insulating rings alternately layered with one another. The slip ring device further includes a plurality of brushes held by the main case and tip end portions making sliding contact with outer circumferential surfaces of the electricity-collecting rings and a plurality of lead lines introduced into the shaft. The lead lines include tip end portions electrically connected to the respective electricity-collecting rings. Two or more of the lead lines include shielded lines.