Abstract:

In order to solve the problems of jitter, slow translational speed and high pump pressure when the hydraulic arm falls due to the structure mismatch between the jumbo arm positioning system and the hydraulic arm，the reason of jitter of hydraulic arm is analyzed systematically, and it is pointed out that the jitter of the hydraulic arm is caused by the instability of the hydraulic cylinder balance valve under the hydraulic arm.And through the test, if the pilot oil source pressure of the lower hydraulic cylinder balance valve is always greater than the opening pressure, the hydraulic arm can gently decline. The jitter problem of hydraulic arm drop can be solved by increasing the pressure of hydraulic arm oil source and increasing the back pressure of the lower hydraulic cylinder.

Key words: jumbo, arm positioning system, hydraulic arm, double triangle translational mechanism, structure mismatch, drop jitter