| 摘要 |
PURPOSE:To prevent abnormal stop of a diaphragm pump by setting in front of the middle point of the movable range of a spool the moving range of the spool over which the spool is pressed by a center rod. CONSTITUTION:A diaphragm pump includes a center rod 3 connecting diaphragms disposed in a pair of respective pump rooms and a spool 4 which engages with the center rod 3 such that it can freely slide within a predetermined range. A reversing spring is provided which energizes the spool 4 and whose reversing position in the direction of energization is located at the middle point of the moving range of the spool 4. Further, a switching valve 5 is provided which by movement of the spool 4 switches the flow of a fluid for driving both of the diaphragm. The moving range of the spool 4 over which the spool 4 is pressed by the center rod 3 does not extend beyond the middle point of the movable range of the spool 4. The spool 4 passes the middle point by its own inertia. Therefore, abnormal stop of the diaphragm pump is prevented. |
