Abstract: To provide a small-sized brushless motor in which a rise in the temperature of power elements can be reduced. A stator (2) is disposed on the same axis as an output shaft (1a) of a rotor (1). A first wiring board (3a) on which power elements (7) are mounted is disposed at the ends of the rotor (1) and the stator (2). A second wiring board (3b) is disposed between the rotor (1) and the first wiring board (3a) so as to partition the inside of a motor casing (4). Magnetoelectric conversion elements (5) are disposed on the second wiring board (3b) in close vicinity to the rotor (1). Stator windings (22) are connected to the first wiring board (3a).

Abstract: A motor for driving an actuator used such as for a throttle valve of an automobile engine and an optical axis controller of an automobile headlight. In two cup-shaped rotor yokes each provided with an internal diameter enlarged part at its opening, a ring-shaped joint material with an external diameter fitting into this internal diameter enlarged part is inserted into the internal diameter enlarged part to form a rotor yoke assembly. A motor is available with high durability against vibration and shock owing to high accuracy in dimensions, lightweight, and high rigidity of the rotor.

Abstract: A magnetic position detecting device for detecting a position of a moving body to a fixed body on the basis of a change of a magnetic flux density that a Hall element on the fixed body senses when the moving body provided with a magnet moves relative to the fixed body. An S-pole and an N-pole of the magnet are juxtaposed along a direction of the movement. When the Hall element passes a boundary between the poles of the magnet, the sensed magnetic flux density is zero, the polarities of the magnetic field are inverted, and therefore the Hall element does not sense any variation of the position. Only when the magnet and the Hall element mutually approach, a detect signal based on the sensed magnetic flux density is compared with a reference signal. By detecting a position where both the signals are equal in level, a reference position is detected.

Abstract: To provide a magnetic position detecting device which is capable of extremely accurately detecting a reference position.

Abstract: A stepping motor includes (a) a rotor being driven by exciting a driving coil, (b) a position detector including a magnetic flux generator for outputting a signal in the same phase as a polarity position of a magnet mounted to the rotor and a magnetic sensor receiving magnetic force from the magnetic flux generator, (c) a controller for controlling the stepping motor responsive to a position detection signal supplied from the position detector, (d) a board on which the magnetic sensor and the controller are mounted, and (e) a sensor cover for positioning the magnetic sensor, dissipating heat of the controller and for covering at least a part of the position detector and the controller. This structure allows the controller and the magnetic sensor to avoid the heat generated by the stepping motor.