摘要 |
<p>PCT No. PCT/JP89/00203 Sec. 371 Date Oct. 17, 1989 Sec. 102(e) Date Oct. 17, 1989 PCT Filed Feb. 28, 1989 PCT Pub. No. WO89/08291 PCT Pub. Date Sep. 8, 1989.A flow control valve assembly, for preventing the pressure oil confined in an inlet port of a valve housing from pulsating and for additionally performing a safety valve function without employing a separate safety valve, has a valve housing which is easy in machining thereof and neat in construction. In the valve housing of the flow control valve assembly is formed a valve-receiving bore (21) in which a poppet (32) and a second spool valve (51), serving as a safety valve, are axially aligned with each other in series. In the valve housing (20), a hydraulic operating oil flows to a communication port (39) of the poppet (32) through an inlet port (23) formed in the valve housing (20), and then further flows to a back-pressure chamber portions (38a, 38b) of the poppet (32) through a variable orifice (44). The pressure oil, having been received in the back-pressure chamber portion (38b), flows out of the portion (38b) to an outer peripheral portion of the second spool valve ( 51). On the other hand, the pressure oil confined in the inlet port (23) flows to a pressure-receiving chamber (56) of the second spool valve (51).</p> |