Patent ReferencesOperating oil introduction type electromagnetic valve Patent #: 4763872 InventorsAssigneeApplicationNo. 333081 filed on 04/04/1989US Classes:137/625.64, Electric137/625.61, Variable orifice-type modulator251/36With separate dashpot or choked fluid retarding chamberExaminersPrimary: Michalsky, Gerald A.Foreign Patent References
International ClassF15B 013/043Foreign Application Priority Data1988-04-20 JPAbstractAn electromagnetic proportional control valve apparatus comprises a valve body, a spool accommodated in a guide bore in the valve body, a valve seat element arranged at one end of the guide bore and facing toward the spool, a pilot valve controlling a valve bore in the valve seat element, and an electromagnetic drive unit for controlling the pilot valve. The spool has an axially extending axial bore formed in an end face opposed to the valve seat element, and a first restricting bore through which the axial bore communicates with the supply port. A projecting portion is formed on an end face of the valve seat element opposed to the spool, and is inserted in the axial bore in the spool. The projecting portion has a forward part formed therein with second restricting bores through which one end of the valve bore communicates with the axial bore. A restricting passage is defined between an outer peripheral surface of the projecting portion and an inner peripheral surface of the axial bore in the spool. A fluid accumulating chamber defined between opposed faces of the respective spool and valve seat element communicates with the axial bore in the spool through the restricting passage. Flow resistance at the restricting passage gives a damper effect to the spool. | |