The cylinder block is connected to the splines on the main shaft to rotate with the main shaft. The plunger assembly is installed inside the cylinder block that moves with the swashplate. The plunger moves from the bottom dead center to the top dead center and moves in the direction of increasing the outlet flow. After the hydraulic oil passes through the oil suction port, it flows to the cylinder block through the port plate (oil suction process). During the journey from top dead center to bottom dead center, the plunger always moves in the direction of reduced oil discharge, so the hydraulic oil is discharged through the oil discharge port (oil discharge process). The amount of oil drained varies with the inclination of the swashplate. The hydraulic oil sucked through the oil suction port of the cylinder block is discharged through the oil discharge port of the valve plate, while the hydraulic oil sucked through the oil suction port of the outer (inner) ring of the cylinder is discharged through the oil discharge port of the outer (inner) ring of the valve plate.
