PURPOSE: To facilitate the adjustment of a pump in the direction that increases an output volume by improving a adjusting spool of an adjusting valve controlling an adjusting piston, in an article controlling the capacity by radially displacing a rolling ring with the adjusting piston capable of being loaded by hydraulic pressure.
CONSTITUTION: A vane pump 1 has a rolling ring 2 serving as a variable capacity element, which is loaded in the direction that increases an output volume with a large diameter adjusting piston 4 capable of being loaded by hydraulic pressure, and loaded in the direction that decreases an output volume with a small diameter adjusting piston 3. A control chamber 8 for the piston 3 is connected to a pressure conduit 10 of the pump 1, and a control chamber 11 for the piston 4 is connected to a regulating valve 13, and then connected to a spool chamber 32 or 39 according to a displacement of a regulating spool 14 of the regulating valve 13. The spool chamber 39 is connected to a control chamber 29 communicating with the pressure conduit 10, through a lateral hole 40, and the spool chamber 32 is connected to the control chamber 29 through a throttle 31 and the lateral hole 40 which are formed on the spool 14.
RAINAA KUNERU
HORUSUTO FUITSUSHIYAA
