| 摘要 |
A vacuum operable unit for use in an ignition distributor of an internal combustion engine comprising a casing divided into first and second chambers by a diaphragm. A push rod is coupled to the diaphragm and extends through one wall of the first chamber, a seal engaging the wall of the chamber and the push rod so as to permit movement of the push rod with the diaphragm, while sealing the first chamber. First and second springs are positioned in the first and second chambers respectively, and either spring is operable on the diaphragm as the diaphragm moves in a direction to reduce the volume of the respective chamber. The housing supports a pair of abutments associated with the springs respectively, the springs engaging their respective abutments when the diaphragm is in a central position, so that in the central position neither spring acts on the diaphragm. |
