Abstract: A drive system for a brushless motor. The brushless motor includes a rotor having opposite magnetic poles on its periphery, and a stator facing the rotor. The stator has, for example, three interconnected coils at equal angular intervals. The drive system includes a memory for storing drive data which represent drive currents supplied to the respective coils at each angular position of the rotor. The drive system also includes a controller for reading those drive data which best match a target angular position of the rotor, from the memory. The controller generates drive signals based on the drive data. The drive system also includes a drive circuit for supplying the drive currents to the respective coils, based on the drive signals, respectively. The drive system can precisely control the angular position of the brushless motor.

Abstract: A positioning apparatus having a brushless motor, a positioning mechanism, and a motor control circuit to rotate a rotor of the brushless motor by sequentially supplying a driving pulse to a plurality of fixed coils of the brushless motor. The motor control circuit includes a driving pulse generator, a present stage number detector to detect a present stage number of the rotor in accordance with an output signal from at least one magneto-sensitive device of the brushless motor, an initializer to move the movable member to at least a forward or a backward traveling limit within the movable range so as to set the rotor present stage number, and a speed reducer to reduce a rotating speed of the brushless motor by reducing power of the driving pulse when the rotor present stage number is equal to at least a forward traveling or a backward traveling stage number.

Abstract: A positioning controller includes a gear mechanism having a rotating gear for positioning a movable member, a brushless motor to drive the rotating gear, and a motor control circuit to rotate a rotor of the brushless motor by sequentially supplying a driving pulse to a plurality of fixed coils of the brushless motor. The motor control circuit includes a present stage number detector to detect a present stage number of the movable member in accordance with an output signal from a magneto-sensitive device of the brushless motor, and a driving pulse generator to generate a driving pulse to rotate the rotor until a target stage number converted from a specified position of the movable member is equal to the present stage number. The controller in an apparatus including a motor driving unit allows positioning of the movable member without using a component for the detection of the position of the movable member.

Abstract: A positioning apparatus according to the present invention includes a brushless motor, a positioning mechanism to position a movable member within a predetermined movable range in accordance with rotation of the brushless motor, and a motor control circuit to rotate a rotor of the brushless motor by sequentially supplying a driving pulse to a plurality of fixed coils of the brushless motor.

Abstract: A drive system for a brushless motor. The brushless motor includes a rotor having opposite magnetic poles on its periphery, and a stator facing the rotor. The stator has, for example, three interconnected coils at equal angular intervals. The drive system includes a memory for storing drive data which represent drive currents supplied to the respective coils at each angular position of the rotor. The drive system also includes a controller for reading those drive data which best match a target angular position of the rotor, from the memory. The controller generates drive signals based on the drive data. The drive system also includes a drive circuit for supplying the drive currents to the respective coils, based on the drive signals, respectively. The drive system can precisely control the angular position of the brushless motor.

Abstract: A positioning controller includes a gear mechanism having a rotating gear for positioning a movable member, a brushless motor to drive the rotating gear, and a motor control circuit to rotate a rotor of the brushless motor by sequentially supplying a driving pulse to a plurality of fixed coils of the brushless motor. The motor control circuit includes a present stage number detector to detect a present stage number of the movable member in accordance with an output signal from a magneto-sensitive device of the brushless motor, and a driving pulse generator to generate a driving pulse to rotate the rotor until a target stage number converted from a specified position of the movable member is equal to the present stage number. The controller in an apparatus including a motor driving unit allows positioning of the movable member without using a component for the detection of the position of the movable member.