| 摘要 |
PURPOSE:To obtain a sound absorbing effect while a plunger is attracted by forming a solenoid body with a plunger which operates when a power is applied to the coil, a frame, a stationary iron core, a bobbin and a rubber ring, etc. and providing an aperture and a valve means which opens or closes it to the frame. CONSTITUTION:A solenoid is formed with a plunger 1 which operates when a power is supplied to a coil, a rubber ring 6, a frame 2, a stationary iron core 3, and a bobbin 5 with hermetical sealing structure. An aperture 20 which connects the inside and outside is provided to the frame 2 and the aperture 20 is formed to open or close freely by a valve means 21. The valve means 21 is formed by an elastic material and is provided within the frame 2. In case an internal pressure of solenoid is higher than external pressure, the aperture 20 is closed in order to prevent the outflow of internal air. In case an internal pressure is lower than external pressure, the aperture 20 opens in order to allow inflow of external air. For this purpose, when the plunger is attracted, sound absorbing effect can be obtained owing to the air dumper effect and when the plunger is isolated, adverse effect to the load being connected can be eliminated by lowering the air dumper effect. |
