Sealed multi-stage hydraulic cylinder

Abstract

The invention relates to the technical field of hydraulic cylinders, in particular to a sealed multi-stage hydraulic cylinder which comprises a hydraulic cylinder body, a first telescopic rod is slidably connected to an inner cavity of the hydraulic cylinder body, a second telescopic rod is slidably connected to an inner cavity of the first telescopic rod, and a round pipe is installed in the top of the hydraulic cylinder body. A plurality of air blowing pipes are evenly installed at the top of the round pipe, telescopic pipes are fixedly installed at the top ends of all the sets of air blowing pipes, L-shaped plates are connected to the pipe walls of all the sets of telescopic pipes in a sleeving mode, a reciprocating lead screw is driven by a motor to rotate, up-down reciprocating motion of a movable block can be achieved, and a U-shaped frame is driven to move up and down through cooperation of an inclined block and a first spring; and therefore, dust can be blown away from the first telescopic rod and the second telescopic rod which are retracted in sequence all the time, the situation that the first telescopic rod and the second telescopic rod are abraded due to residual dust during retraction can be effectively avoided, and the service life of the device can be effectively prolonged.

Description

technical field [0001] The invention relates to the technical field of hydraulic cylinders, in particular to a sealed multi-stage hydraulic cylinder. Background technique [0002] Telescopic hydraulic cylinders are also called multi-stage hydraulic cylinders. It consists of a two-stage or multi-stage piston cylinder set, mainly composed of cylinder head, cylinder barrel, sleeve, piston and other parts. There are inlet and outlet ports A and B at both ends of the cylinder. When the A port enters the oil and the B port returns the oil, the first-stage piston with a larger effective area is pushed to move, and then the smaller two-stage piston is pushed to move. Because the flow into port A remains unchanged, the piston with a large effective area moves at a low speed and has a large thrust; otherwise, the piston moves at a high speed and has a small thrust. If oil enters port B and returns oil to port A, the second-stage piston will return to the end point first, and then t...

AI Technical Summary

Problems solved by technology

[0004] In the process of realizing the above-mentioned invention, the applicant found that there are some problems in the invention: hydraulic cylinders are usually used to support objects, especially in the repair shop, and when repairing cars and trucks, the bottom of the When supporting, due to the long-term driving of cars and trucks, a lot of dust will inevitably fall on the bottom, and it is easy to fall on the outer wall of the hydraulic cylinder telescopic rod, which will cause the telescopic rod to be prone to friction and wear when it is retracted. Reduced service life of hydraulic cylinders

Images