| 摘要 |
An hydraulic actuator for a spring closed poppet valve is connected to an electrically motivated valve selecting a high or a low fluid pressure source for a chamber in which a plunger reciprocates in a cylindrical body. Poppet valve closing is controlled by restricting fluid flow from the chamber to the low pressure source. Initially, closing flow is through a closing check valve and is gradually cut off by a frusto-conical end of the plunger. Closing flow is then restricted by an orifice bypassed by a snubber check valve during poppet valve opening. The closing check valve, an opening port, and a recuperation check valve open radially through the body. The closing check valve and the opening port communicate with an annular body groove connected to the electrically motivated valve. The recuperation check valve communicates with the plunger chamber beyond the plunger end and opens directly to the high pressure source when the closing kinetic energy of the actuator elements and poppet valve develops an even higher pressure due to the restricted closing flow. Some of this energy is thus recuperated for poppet valve opening. |
