1. The oil pressured from pump enters the distributor, so that the umbrella valve in the distributor starts to push upward.
2. After the umbrella valve closes the hole in the center of the core rod, the piston is forced to overcome the spring force to start to rise, and the oil stored in the upper chamber is discharged.
3. When the piston moves to the top of the upper chamber, the oil discharge is completed at the same time.
4. When pump stops supplying oil, its pressure relief valve is automatically opened, and the pressure in the main oil pipe causes the pressure relief valve to start the work of returning oil. At this point the system pressure drops and the piston in the distributor begins to return under the action of the spring. When the umbrella valve returns until the oil inlet of the distributor is closed, the piston presses the oil stored in the lower chamber to the upper chamber through the small hole of the core rod, oil storage work is completed.