2) REGULATOR Regulator consists of the negative flow control, total horse power control and power shift control function. (1) Negative flow control By changing the pilot pressure Pi, the pump tilting angle(delivery flow) is regulated arbitrarily, as shown in the figure. This regulator is of the negative flow control in which the delivery flow Q decreases as the pilot pressure Pi rises. With this mechanism, when the pilot pressure corresponding to the flow required for the work is commanded, the pump discharges the required flow only, and so it does not consume the power uselessly. Delivery flow, Q Pilot pressure, P i 2-10