The principle of hydraulic jacks is based on Pascal's principle, that is: the pressure of the liquid is the same everywhere, so that in a balanced system, the pressure exerted on the smaller piston is relatively small, and the pressure exerted on the large piston is relatively large, so that Able to keep the liquid still.

Therefore, through the transmission of the liquid, different pressures on different ends can be obtained, so that a transformation purpose can be achieved. The hydraulic jacks we see commonly use this principle to achieve force transmission.

Hydraulic jacks are suitable for various lifting operations with small lifting heights. It consists of: oil chamber, oil pump, oil storage chamber, piston, crank handle, oil valve and other main parts. When working, as long as the crank handle is moved back and forth, the manual oil pump continuously presses oil into the oil cylinder. Due to the continuous increase of the oil pressure in the oil cylinder, the piston and the weight on the piston are forced to move upward together. Open the oil return valve, and the high-pressure oil in the oil cylinder will flow back to the oil storage chamber, so the weight and the piston will fall together.