SWITCH AS-TEMPERATURE 1498292 - Caterpillar

Pump Regulator
Illustration 1 g03871300
(1) Pilot pump
(2) Pump regulator Pilot pump regulator (2) is mounted on the side of pilot pump (1). The pilot pump regulator controls the output of the pilot pump.
Illustration 2 g03871345
Section view of pump regulator (2)
( 3) Spool (flow compensator)
(4) Port "X" - signal oil
(5) Springs (flow compensator)
(6) Adjustment screw (flow compensator)
(7) Adjustment screw (pressure compensator)
(8) Springs (pressure compensator)
(9) Port "T" - oil flow to case drain
(10) Port "A" - oil flow to the actuator piston
(11) Port "P" - oil flow from the output port of the pump
(12) Spool (pressure compensator) The pump control valve contains a pressure compensator and a flow compensator. The pump control valve keeps the pump pressure and the pump flow at the level that is required of the pilot system. When the hydraulic circuits are not active, the pump is at low-pressure standby. However, if one or more circuits are active, the load signal resolver compares the signal pressure of the hydraulic system. The highest resolved signal pressure is then routed to the pressure and flow compensator valve. The pump control valve adjusts the swashplate angle of the pump in order to maintain flow and pressure requirements. The margin pressure is defined as the difference between the pump pressure and signal oil through port (4) with the force of springs (5).The pump control valve limits the pressure in order to prevent overloads of the hydraulic system.When the system pressure exceeds the setting of the pump control valve, the pressure compensator will override the flow compensator. The output flow of the pump will be lowered. Lowering the output flow will protect the hydraulic system from damage due to high pressure.