How does the jack lift the weight?

Jack is a kind of light and small lifting equipment that uses steel jacking parts as working devices and lifts heavy objects through the top bracket or bottom claw within the stroke. It is mainly used in factories, mines, transportation and other departments as vehicle repair and other lifting, support and other work. Its structure is light and solid, flexible and reliable, and one person can carry and operate it.

Jacks are divided into mechanical and hydraulic types. Commonly used jacks include hydraulic jacks, screw jacks and electric jacks.

In principle, the basic principle of hydraulic transmission is Pascal’s law, that is, the pressure of liquid everywhere is consistent. In the balance system, the pressure exerted by the smaller piston is relatively small, while the pressure exerted by the larger piston is also relatively large, which can keep the liquid static. Therefore, through the transmission of liquid, different pressures on different ends can be obtained, and the purpose of a transformation can be achieved. The hydraulic jack commonly used by people uses this principle to achieve force transmission.

Basic equation of static pressure (p=p0+ ρ GH), when the external pressure P0 of the liquid contained in the closed container changes, as long as the liquid remains in its original static state, the pressure at any point in the liquid will change by the same amount, which is the static pressure transfer principle or Pascal principle.

If a certain pressure is applied to one piston in the hydraulic system, the same pressure increment will be generated on the other piston. If the area of the second piston is 10 times that of the first piston, the force acting on the second piston will increase to 10 times that of the first piston, while the pressure on the two pistons is still equal.

The screw jack pulls the handle back and forth, pulls out the claw, that is, it pushes the ratchet clearance to rotate, and the small bevel gear drives the big bevel gear to rotate the lifting screw, so that the lifting sleeve can be lifted or lowered to achieve the function of lifting tension, but it is not as simple as the hydraulic jack.