| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce noise generated in performing pulse width modulation control of a supply current to a coil in a solenoid comprising the coil and a yoke. SOLUTION: The yoke 144 comprises an outer peripheral side yoke 152 and an inner peripheral side yoke 150. The plate thickness of an annular part 164 of the outer peripheral side yoke 152 is almost double the plate thickness of an inner cylinder part 166 and an outer cylinder part 168. As a result, the outer peripheral side yoke 152 hardly bends in the direction of an arrow mark X. With pulse width modulation control performed to a supply current to the coil 142, the current is oscillated, and the generated magnetic field is oscillated, but the oscillation of the outer peripheral side yoke caused by the oscillation can be suppressed, and noise caused by the oscillation can be reduced.</p> |
