Hydraulic jack with combined anti-rebound check valve

Abstract

The invention discloses a hydraulic jack with a combined anti-rebound check valve, which is characterized in that: a serial check valve body in clearance fit with a positioning hole of a base is arranged between an oil pumping oil circuit and a working oil chamber of an oil cylinder, and is provided with a seal assembly; the upper part of the serial check valve body is provided with a first check valve chamber, while the lower part is provided with a second check valve chamber; an oil circuit hole of the valve body is communicated with the first and second check valve chambers; the first check valve chamber is directly communicated with the working oil chamber of the oil cylinder above the first check valve chamber; a center line of a hole of the second check valve chamber is eccentrically formed on one side of the center line of the oil circuit hole of the valve body; a first steel ball of the serial check valve forms a check valve seat at the upper hole of the oil circuit hole of the valve body; and a second steel ball of the serial check valve forms another check valve seat at a second oil pumping oil circuit hole. The two stages of oil pumping check valves are effectively connected in series in the serial check valve body, so the hydraulic jack avoids a serious defect that one stage of check valve cannot lock the high pressure oil to cause a handle to rebound to injure an operator.

Description

technical field [0001] The invention relates to a hydraulic jack, in particular to a hydraulic jack combined with an anti-rebound check valve. Background technique [0002] The existing oil pressure technology of hydraulic jacks all over the world almost all adopts the pressure-holding structure of the first-level one-way valve steel ball to lock the valve seat. It is because the hydraulic jack has caused injury to many users in dynamic load operation or actual combat use. The author, as an operator, was also injured by the sudden failure of the check valve seat of this traditional structure more than ten years ago. The permanent rebound operating handle severely injured the face, mouth, lips, and teeth. Therefore, for a long time, I have been worried about this potential safety hazard of the hydraulic jack. [0003] After the traditional hydraulic jack is tightened with the oil return valve, the pump core assembly is reciprocated up and down, so that the hydraulic oil can ...

AI Technical Summary

Problems solved by technology

People's analysis of the structural failure of this hydraulic jack check valve is as follows: the base or oil cylinder seat of the hydraulic jack generally adopts castings such as poured steel and ductile iron, and inherent defects such as shrinkage and looseness on the check valve seat Material defects such as trachoma and air holes and residual garbage particles in the hydraulic oil are sometimes coincidentally positioned near the above-mentioned high-pressure one-way valve seat, which is difficult to be found in general metal processing and inspection. The valve seat is suddenly damaged by high-pressure oil, and the valve seat is no longer complete, and there is no way to talk about maintaining pressure; also sometimes the valve seat happens to be blocked by garbage particles in the hydraulic oil, which have entered the high pressure of the working oil chamber of the cylinder. The oil cannot be locked in it. In both cases, the high-pressure oil will flow back to the pump chamber in an instant and cause the consequences of injuring the human body.

For a long time, people have analyzed the causes and hazards of this high-voltage rebound, but they cannot effectively overcome it. Therefore, the manufacturer can only emphasize to customers that the human body should deviate from the operating handle as much as possible during operation, but accidents still occur.

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