| 摘要 |
Disclosed is a valve that works by means of a poppet or spool that covers a port in a first position and then switches to cover a second opposite port in a second position. In each of the two positions, the poppet or spool separates the covered port from a third port and connects the third port to the second port, reversing the connection in the second position. To ensure a fast response, the poppet or spool has minimal mass, and consequently minimal inertia, and switches between the two positions over a short distance under the effect of an actuator, returning under the effect of a spring, a liquid (or gas, in the case of other applications) under high pressure and which can provide a large drive force, or both together. The high pressure acts on two adjacent surface areas on both sides of the poppet or spool, providing two important features: firstly, the actuator needs to provide enough force to counter the force resulting from the effect of the high pressure on the difference of the two surface areas only, and not on the large lateral surface area of the poppet; and secondly, the thickness of the poppet disc can be significantly reduced, greatly reducing the mass thereof, and consequently the inertia of same. In particular cases, two ports can be used instead of three, and the two ports can be connected to the third port by means of high pressure that is used as control pressure during the rapid return of the poppet. A permanent separation or connection can also be created between any two lines in either operating position. The valve can be used with compressed air in pneumatic control, using suitable production materials, as well as in hydraulic control. |
