Internal structure of the screw jack

The screw jack, also known as the mechanical jack, is driven by a manpower through a screw pair, and a screw or nut sleeve is utilized as a jacking member. The normal screw jack supports the fat by the thread self-locking function, and the structure is simple, however the transmission performance is normally low and the return stroke is slow. The thread of the self-propelled screw jack has no self-locking action and is equipped with a brake. When the brake is certainly released, the weight could be quickly lowered alone and the return period can be shortened, but the structure of the jack can be complicated. The screw jack can support heavy objects for a long time, and the utmost China Air Compressor lifting capacity has reached 100 tons, which is widely used. After the horizontal screw is normally mounted on the low part, the weight can be traversed at a little distance.

Principle useful:

The mechanical jack is one of the types of manual lifting tools. Its compact framework makes reasonable use of the rocking of the rocker to rotate the pinion. It really is operated by a pair of conical gears to operate a vehicle the screw to rotate and push the lifting sleeve so that the weight rises or decline.


1. Before use, it’s important to check whether the jack is regular, whether the parts are flexible, put lubricating oil, and properly estimate the pounds of the large object. Use a jack of appropriate tonnage and prevent overloading.

2. Adjust the technique of supporting one’s teeth on the rocker. Firstly, turn the rocker directly in the clockwise path by hand to help make the lifting sleeve quickly ascend the top weight.

3. Insert the handle in to the rocker hole, move the deal with up and down, and the fat will rise. When the reddish warning line appears on the lifting sleeve, the handle should be stopped immediately. If you need to lower the teeth in the opposite direction, the excess weight will begin to fall.


1. Usually keep the surface of the machine clean, examine the internal structure regularly, make the pinion in the rocker flexible and reliable, and lift the lifting sleeve openly.

2. The friction surface between the lifting sleeve and the casing must be oiled anytime. Other oil filling holes should be lubricated regularly.

3. To be able to consider the security in use, avoid overloading, use illness, it isn’t appropriate to use multiple units to avoid danger.