PILOT PRESSURE OPERATED DIRECTIONAL CONTROL VALVE AND OPERATION CYLINDER CONTROL DEVICE

摘要

A pilot pressure operated directional control valve is provided in which a housing is formed therein with a spool having a plurality of ports, the said spool bore has a spool fittingly inserted therein so as to be slidably displaceable therein and the said spool is slidably displaced both by a spring and under a pilot pressure led into a pressure receiving chamber, and in which a spring box is attached to an end surface of the said housing in a longitudinal direction of the said spool; and the said spring box is provided with a hollow portion which contains the said spring while forming a pressure receiving chamber, as well as a pilot pressure fluid inlet that communicates with the said hollow portion and that is opening in the longitudinal direction of the said spool.