Power Steering Pump: Description and Operation
FLUID PUMP AND RESERVOIR TANK2. 3.0L MODEL
The reservoir tank is mounted on the vehicle body.
The fluid pump is belt-driven by the engine. The fluid flow is controlled according to the engine speed so that an adequate steering resistance is given during high-speed operation.
The fluid pump is a variable capacity type vane pump whose delivery rate per rotation decreases as the engine speed increases. The pump is integral with a pump control valve and relief valve.
The oil pump is driven by the engine and its flow is controlled in accordance with the engine speed to maintain an adequate steering effort at high speeds.
Also, to improve fuel efficiency and limit temperature rise of the system, a variable displacement vane pump shose output flow per rotation is controlled in accordance with the engine speed is used, and a control valve and a relief valve are built in the pump.
The vane pump consists of a rotor, a cam ring, adapter, and eleven vanes.
When the rotor rotates, the vane in each slot of the rotor is radially moved out by centrifugal force and pressed against the cam ring. The fluid from the suction port is confined in chambers formed between two adjacent vanes and carried to the discharge port. Since the cam ring is movable in relation to the rotor, the volume of each chamber is variable. This enables the delivery rate per rotation of the pump to be changed.