CONTROL CIRCUIT FOR VARIABLE CAPACITY PUMP

摘要

PURPOSE:To reduce the number of parts in control circuit thus to reduce the size by varying the opening area of orifice through manual changeover valve and leading the pilot pressure produced across said orifice to a regulator for setting the inclination angle of pump. CONSTITUTION:The control port 11a of manual changeover valve 11 will constitute a variable orifice for varying the opening with correspondence to the movement of spool section 11h of said valve 11. Upon switching of said valve 11 from neutral position to the left or right, pilot pressure is produced in a branch path 15 in the upstream of said valve 11 while corresponding with the changing amount. Said pilot pressure is led to a regulator 19 and functions to vary the delivery of variable capacity pump P1.