Seiko Instruments Inc

Seiko Watch Kabushiki Kaisha

Seiko Watch Kabushiki Kaisha (trading As Seiko Watch Corporation)

Akihito Okumura

Kosuke Yamamoto

Kazumi Sakumoto

Tomohiro Ihashi

Tetsuya Nobe

Kazuo Kato

Kenji Ogasawara

Satoshi Sakai

Ryosuke Isogai

A stepping motor control device configured to drive a stepping motor having a rotor and a coil includes: a train wheel including a load gear which has a load tooth whose rotation load is different from that of another tooth and in which the rotor has an odd number of rotation steps when the load gear rotates once, and transmitting a rotation force from the rotor to the hand; a voltage detection unit that detects an induced voltage generated at one end portion of a first end portion and a second end portion of the coil when the rotor vibrates; and a determination unit which, based on a result detected by the voltage detection unit, determines a mechanical load received by the rotor due to contact of the load tooth of the load gear with a tooth meshing with the load gear.

Stepping motor control device, movement, timepiece, and stepping motor control method

A stepping motor control device includes a driving unit that drives a stepping motor including a rotor that rotates a hand and a coil that generates a magnetic flux for rotating the rotor, a control unit that outputs, to the driving unit, a driving pulse for rotating the rotor and a swinging pulse for swinging the rotor, a voltage detecting unit that detects an induced voltage generated in the coil when the rotor vibrates, and a determining unit that determines, based on a result of the detection of the voltage detecting unit, a mechanical load received by the rotor.

A motor driving apparatus including a driving circuit for supplying a first pulse with which a first coil included in a two-phase stepping motor generates a first magnetic flux, a second pulse with which a second coil included in the stepping motor generates a second magnetic flux opposite to the first magnetic flux, a third pulse with which the first coil generates the second magnetic flux, and a fourth pulse with which the second coil generates the first magnetic flux, to the stepping motor. The driving circuit supplies the second pulse, the third pulse, and the fourth pulse in this order to the stepping motor in a state of being stopped to start the stepping motor, and supplies the first pulse, the second pulse, the third pulse, and the fourth pulse in this order to the stepping motor after starting to continuously drive the stepping motor.

Motor driving apparatus, motor driving method, and timepiece

A stepping motor control device is configured to drive a stepping motor by applying a normal drive pulse or a fixed pulse having an energy larger than that of the normal drive pulse. The stepping motor control device includes a determination unit configured to, based on whether or not a pulse applied to the stepping motor before the normal drive pulse is the fixed pulse, determine whether or not to add a degaussing pulse is applied to the normal drive pulse, the degaussing pulse being a pulse for canceling a residual magnetic flux generated in a stator of the stepping motor when the fixed pulse; and a drive control unit configured to, based on a determination result of the determination unit, drive the stepping motor with the normal drive pulse to which the degaussing pulse is added.

Stepping motor control device, timepiece and method for controlling stepping motor

There is provided an analog electronic timepiece including a stepping motor in which a rotor magnetized in two poles is rotationally driven in a stator connected to a driving coil, a drive circuit for applying a drive pulse to the driving coil, the drive pulse being a pulse for driving the rotor, and a control unit for controlling application of the drive pulse by the drive circuit, in which when an induced voltage induced in the driving coil by rotation of the rotor satisfies a predetermined condition related to the induced voltage, the control unit controls the drive circuit so that the drive pulse is applied to the driving coil before free vibration of the rotor is settled.

Analog electronic timepiece, stepping motor control device, and analog electronic timepiece control method

A timepiece includes a voltage detection unit that detects a voltage applied to a stepping motor for driving an indicating hand, and that outputs a voltage detection result, and a drive control unit that controls a rotor to perform reverse rotation by using a reverse rotation pulse including a first pulse whose polarity is the same as that of a normal rotation pulse for causing the rotor of the stepping motor to perform normal rotation, a second pulse whose polarity is reverse to that of the first pulse, and a third pulse whose polarity is reverse to that of the second pulse, and to control the rotor to perform the reverse rotation by using the third pulse having a pulse width set in accordance with the voltage detection result.

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Chiba, Japan

Akihito Okumura