The relationship between the area A1 affected by the oil pressure of the upper chamber and the area A2 affected by the oil pressure of the lower chamber is A1 > A2, and A2 is always under high pressure. When A1 is changed from high pressure to low pressure, the piston moves upward, which is accompanied by high pressure nitrogen storage in the rear cylinder.
(1) piston upward
Initial case: piston and valve are located at their lower ends. When the upper chamber of the cylinder is subjected to low pressure, the high pressure chamber of the cylinder body and the valve will always be subjected to high pressure. The low pressure chamber connected to the oil return port is always in a low pressure state. The low pressure chamber is connected with the cylinder transfer chamber, and the A5 connected with the cylinder transfer chamber is subjected to low pressure, so the cylinder transfer chamber is subjected to low pressure before the piston moves upward.
Because the area A3 and A4 are subjected to high pressure (A3. A4), the valve is subjected to downward force before the A5 is subjected to high pressure.
High pressure oil enters the lower chamber of the cylinder to make the piston rise.
When the piston starts to move upward, the oil pressure in the piston conversion chamber does not change.
When the piston moves upwards, the high pressure nitrogen is pressed.
(2) valve upward
When the piston moves to the middle part, the cylinder conversion chamber is connected with the lower cavity, so that the cylinder conversion chamber is subjected to high pressure. A3, A4, and A5 are all subjected to high pressure, and their area is related to A4+A5>A3. The valve is subjected to the upward force valve to move upwards under the force. When the piston stops moving, the high pressure nitrogen accumulating energy reaches the maximum.
(3) the piston is down
When the piston is upwards, the piston conversion chamber is connected with the high pressure chamber inside the valve so that the upper chamber of the cylinder becomes high pressure. The upper and lower chamber are subjected to high pressure, and A1 > A2, the piston is subjected to downward force. On the other hand, high pressure nitrogen pressurized the piston to a downward force, so that the piston moves downward rapidly.
Downward valve
Prior to this, the piston striking rod and cylinder conversion chamber were connected to the low pressure chamber, so that the A5 was subjected to low pressure. A3 and A4 are subjected to high pressure, A3 > A4, so the valve moves downward.
Piston work
When the valve moves downward, the piston strikes the drill rod.
When the piston hits the drill rod, the piston starts to move up.
The hydraulic hammer repeats one to two - three to four to complete the work.
