STROMREGELVENTIL

摘要

A flow control valve for controlling the output at first and second delivery ports in response to the output of a single pump connected to the inlet port of the valve, is disclosed. The valve includes a stepped bore the reduced portion of which is adjacent the inlet port and receives an operating piston having an axial bore therein. The larger portion of the stepped bore receives an auxiliary differential piston having an axial bore which sealingly receives the projecting end of the operating piston. The operating piston is spring-biased toward the inlet port, and the auxiliary piston is spring-biased toward the other end of the stepped bore. The projecting end of the operating piston is provided with a restricted opening which communicates with the first delivery port. The larger portion of the stepped bore is provided with a relatively large opening which is spaced from the other end thereof and which communicates with the second delivery port. The first delivery port also communicates with an intermediate opening in the stepped bore and near the transition of the stepped bore. The reduced portion of the stepped bore communicates with a discharge opening of the valve when the operating piston is translated away from the inlet port. At low pump pressures, the pump communicates with the first delivery port through the axial bore of the pistons. Increased pressure translates the auxiliary piston thereby exposing the large opening to the pump output. A further increase in pump pressure translates the operating piston thereby to divert the excess pump output through the discharge opening of the valve.