| 摘要 |
PURPOSE: To provide a magneto-pneumatic timing device having reliability and whose moving parts are minimum. CONSTITUTION: In a timing device in which magneto-pneumatic pressure is used for providing a pressure signal alternating between a high and a low pressure signal, the duty cycle time and the total cycle time can be changed. A flexible diaphragm 14 magnetically energized separates a chamber 12 into a pair of subchambers 16, 18, so that the pressure difference between the subchambers 16, 18 can be controlled to cause the flexible diaphragm 14 to pull away from the magnetic bias to one position and to return to its biased position. The control of the output pressure signal is carried out by varying the resistance in certain of the pneumatic passages that are part of the control function for the differential pressure. The device is relatively simple and inexpensive to construct and features every few moving parts, thus it is reliable and capable of high production, low cost manufacture. |
