PURPOSE: To prevent chattering of an oil pressure reducing valve by providing an oil damper chamber between the spool end face of a primary spool adjusting pressure of a primary circuit and the plug of a valve case opposite to the spool end face.
CONSTITUTION: Oil pressure from an oil pressure pump is actuated to a primary circuit 1 and a secondary circuit through a pressure reducing valve 9, and when pressure oil flows in the primary circuit 1, the primary circuit 1 is opened by opening motion against the spring 13 of a primary spool 2. At this time resistance is actuated on the spool end face 3 of the primary spool 2 due to the oil damper 6 between itself and a plug 5. The oil damper 6 is provided between the spool end face and the plug 5 closing the spool area of the valve case 4, hence air is not stagnated locally, and chattering or cavitation of the spool 2 and further abnormal sound or the like are hardly generated.
OSHITA JUNICHI
KIKUCHI KAZUYUKI
SHIGEMATSU FUMIO
