Hyundai Excavator R290LC-7 Main Pump Kawasaki K3V140DT Introduction
Posted on 02/12/2023
1. Structure
2. Minimum Flow Control
When the engine is running the swash plate moves to minimum angle position as per the following steps.
The pressure is created by restriction of the foot relief valve.
That pressure apply to the piston A.
The piston A is moved to LH side.
The piston B is opened.
The pressure flows to the piston C.
The piston C is moved to LH side, therefore the swash plate is positioned at minimum flow angle.
2. Maximum Flow Control
When a machine is operating, oil is supplied to the actuator(cylinder or motor) so that no oil pressure reaches piston A.
Then, the piston B goes back to the neutral position by the spring,and the oil in the large chamber of the cylinder C is returned to the tank.
Now the oil is supplied to LH side of the cylinder C.
That pressure moves the piston C to RH side, therefore the swash plate is positioned at maximum flow angle during operation.
