Abstract: A drive device includes stepper motors, each having an excitation coil and a rotor rotating based on variation in the excitation state of the excitation coil; driven members, each moving in accordance with the rotation of the rotor of the corresponding stepper motor; stoppers, each stopping the driven member mechanically at a zero position; and a controller, controlling the respective stepper motors so as to selectively performs either a normal operation in which the stepper motor is driven so as to rotate, or a zero-position detection operation in which the stepper motor is driven so that the driven member is moved to the stopper. The controller starts to perform the zero-position detection operation simultaneously in all of the stepper motors and changes the stepper motor which has terminated the zero-position detection operation to the normal operation without waiting for the termination of the zero-position detection operation in other stepper motors.

Abstract: A drive device includes stepper motors, each having an excitation coil and a rotor rotating based on variation in the excitation state of the excitation coil; driven members, each moving in accordance with the rotation of the rotor of the corresponding stepper motor; stoppers, each stopping the driven member mechanically at a zero position; and a controller, controlling the respective stepper motors so as to selectively performs either a normal operation in which the stepper motor is driven so as to rotate, or a zero-position detection operation in which the stepper motor is driven so that the driven member is moved to the stopper. The controller starts to perform the zero-position detection operation simultaneously in all of the stepper motors and changes the stepper motor which has terminated the zero-position detection operation to the normal operation without waiting for the termination of the zero-position detection operation in other stepper motors.

Abstract: When excited states of excitation coils are controlled at a both excitation step of magnetizing both of two excitation coils, an initializing driving means 41a inputs excitation pulses in which a duty ratio thereof at an interval of time controlled by the both excitation step is less than 1 to the excitation coils. Contact detecting means 42 detects contact based on voltages generated at the excitation coils when the excitation pulses are not inputted.

Abstract: A drive unit for calibrating an indicator/meter of a vehicle is provided in which a pointer in an indicator for a vehicle can point immediately after an ignition switch is turned ON, and the frequency of seeing motion of the pointer in an initializing operation by a car driver is reduced. A sensing mechanism (8a-3) is provided to sense an open/close operation of a door. Correspondingly to the sensing of the sensing mechanism (8a-3), a drive-start mechanism (8a-4) starts rotation of a stepping motor using a drive mechanism (8a-1) for initialization. The drive mechanism (8a-1) during initialization rotates the stepping motor to move a driven member toward a stopper.

Abstract: When excited states of excitation coils are controlled at a both excitation step of magnetizing both of two excitation coils, an initializing driving means 41a inputs excitation pulses in which a duty ratio thereof at an interval of time controlled by the both excitation step is less than 1 to the excitation coils. Contact detecting means 42 detects contact based on voltages generated at the excitation coils when the excitation pulses are not inputted.

Abstract: For providing a drive unit for initialization, in which a pointer in an indicator for a vehicle can point immediately after an ignition switch is turned ON, and frequency of seeing motion of a pointer in an initializing operation by a car driver is reduced, the sensing means 8a-3O senses an open/close operation of a door. Correspondingly to sense of the sensing means 8a-3, the drive-start means 8a-4 starts rotation of a stepping motor by the drive means 8a-1 for initialization. The drive means 8a-1 for initialization rotates the stepping motor to move a driven member toward a stopper.

Abstract: A cross coil type indicating instrument including a coil bobbin having first and second chambers separately formed inside, a rotary shaft to which a magnet rotor and a rotary gear are secured in the first chamber, and an eccentric shaft to which a transmission gear is secured in the second chamber so as to engage with the rotary gear. A pointer is secured to an end portion of the eccentric shaft. Further, the coil bobbin has a coil winding portion with a flat surface outside where the first chamber is formed, and two coils are wound on the coil winding portion in such a manner that they are perpendicular to each other. Hence, the coils are guided linearly when wound on the coil winding portion.