To provide a capacitor controller for hydraulic oil circuit of variable capacity motor, by which operability for changing the cut-off pressure can be enhanced and remote control can be exercised.
In a controller, a balance point of a spool by the set-force of a return spring of a control switching valve 10 is set so that it corresponds to the inlet-side load pressure of a variable capacity motor 1 while the motor 1 is operated at a high speed and under a heavy load, and an inlet-side load pressure detector 24 for the motor 1 is installed in a hydraulic oil circuit 2, and when an ON signal is inputted from a remote control switch 38, the detection value by the pressure detector 24 is compared with the set-value corresponding to the inlet-side load pressure of the motor 1 during its operation at a high speed and under a heavy load, so that the controller makes a regulator 8 switch the motor capacity from a small capacity to a large one when the detection value reaches the set-value. When an OFF signal is inputted by the remote control switch 38, the controller 26 forbids the regulator 8 to perform the operation according to the detection value of the pressure detector 24.