Forklift and forklift mask lifting hydraulic system

Abstract

The invention discloses a forklift mask lifting hydraulic system. The system comprises a working oil way, a main oil return way, at least one lifting oil cylinder and a reversing valve, wherein a rodless cavity of the lifting oil cylinder is connected with the working oil way, a rod cavity of the lifting oil cylinder is connected with the main oil return way through a pipe joint so as to enable the rod cavity and the pipe joint to be connected to form a low-pressure oil return way used for guiding oil liquid to flow back to the rod cavity, and the reversing valve selectively communicates withthe working oil way and the pipe joint. When a heavy object presses a piston rod of the lifting oil cylinder, the piston rod pushes the oil liquid in the rodless cavity to flow into the working oil path, due to the fact that the reversing valve can communicate with the working oil way and the pipe joint, the oil liquid flowing out of the working oil way is returned to the rod cavity and the main oil return way through the pipe joint, so that fluid friction is formed between the piston rod and a cylinder barrel, serious abrasion of the piston rod or the cylinder barrel is avoided, the working failure of the lifting oil cylinder is further avoided, so that the lifting oil cylinder can be stably telescopic, so that a fork works stably. The invention further discloses a forklift comprising theforklift mask hydraulic system.

Description

technical field [0001] The invention relates to the field of forklifts, in particular to a hydraulic system for lifting the mast of a forklift. The invention also relates to a forklift. Background technique [0002] Forklifts carry heavy objects by lifting the forks. They can carry a wide variety of goods and are widely used in logistics, manufacturing, engineering and other fields. Therefore, it is particularly necessary to optimize the performance of forklifts. [0003] In view of the advantages of the hydraulic system with a wide range of speed regulation and large output power, the existing forklifts usually drive the mast to lift through the hydraulic system, and then the mast drives the forks to achieve corresponding actions. The existing forklift hydraulic system includes at least one single-acting piston cylinder whose piston rod is connected with the fork. The rodless chamber of the single-acting piston cylinder is usually connected with the working oil circuit, an...

AI Technical Summary

Problems solved by technology

[0004] It can be deduced from this that during the working process of the single-acting piston cylinder, there is always no hydraulic oil in the rod cavity, which leads to a certain degree of rigid friction between the piston rod and the cylinder barrel, which causes serious wear of the piston rod and affects the stable operation of the fork.

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