Movement and electronic watch
AssigneeSeiko Epson Corporation
InventorsReiko Nagahama, Tomoki Okuhata
Life of this patent
Estimating the term…
Abstract
A stepping motor, a driver, a current detection circuit, a first driving circuit configured to output a first driving signal to the driver, a rotation detection circuit configured to detect rotation of the rotor, and a second driving circuit configured to output a second driving signal selected from plural kinds of the second driving signals with different supply times of the driving current supplied to the coil, and configured to output a correction driving pulse that is preset to the driver when, after outputting the second driving signal, the rotation detection circuit detects that the rotor is not rotating, are included, and a resistance value R[Ω] of the coil and the driving voltage V volts of the stepping motor satisfy 900×V[Ω]≤R[Ω]≤1100×V[Ω], and 1.8 volts≤V≤2.4 volts.
Claims5
A movement comprising:
- a stepping motor including a rotor and a coil,
- a driver configured to supply driving current, corresponding to a driving signal that is input thereto, to the coil,
- a current detection circuit configured to detect a value of current flowing through the coil,
- a first driving circuit configured to output a first driving signal to the driver based on the value of current detected by the current detection circuit,
- a rotation detection circuit configured to detect rotation of the rotor, and
- a second driving circuit configured to output:
- a plurality of second driving signals having different driving current supply periods of time to the driver;
- a first one of the plurality of second driving signals having a first driving current supply period of time to the driver when the rotation detection circuit detects the rotations of the rotor a plurality of consecutive times;
- a predetermined correction driving pulse to the driver when, after outputting one of the plurality of second driving signals, the rotation detection circuit detects that the rotor is not rotating;
- and
- a second one of the plurality of second driving signals having a second driving current supply period of time to the driver after outputting the predetermined correction driving pulse, the second driving current supply period of time being longer than the first driving current supply period of time, wherein
- 900×V≤R≤1100×V, and 1.8 volts≤V≤2.4 volts, where R is a resistance value of the coil, measured in ohms, and V is a driving voltage of the stepping motor, measured in volts, and
- the first driving circuit drives the rotor at a velocity from 300 Hz to 400 Hz.
A movement comprising:
- a stepping motor including a rotor and a coil,
- a driver configured to supply driving current, corresponding to a driving signal that is input thereto, to the coil,
- a current detection circuit configured to detect a value of current flowing through the coil,
- a first driving circuit configured to output a first driving signal to the driver based on the value of current detected by the current detection circuit,
- a rotation detection circuit configured to detect rotation of the rotor, and
- a second driving circuit configured to output a second driving signal selected from plural kinds of the second driving signals with different supply times of the driving current supplied to the coil, and configured to output a correction driving pulse that is preset to the driver when, after outputting the second driving signal, the rotation detection circuit detects that the rotor is not rotating, wherein
- 900×V≤R≤1100×V, and 1.8 volts≤V≤2.4 volts, where R is a resistance value of the coil, measured in ohms, and V is a driving voltage of the stepping motor, measured in volts, and
- the first driving circuit drives the rotor at a velocity from 300 Hz to 400 Hz.
Dependencies are inferred from the claim text.