Structure and method for preventing oil cylinder from rushing out of knuckle arm and lifting arm

Abstract

The invention relates to the field of lifting arms, and discloses a structure and method for preventing an oil cylinder from rushing out of a knuckle arm and a lifting arm. The structure for preventing the oil cylinder from rushing out of the knuckle arm comprises the knuckle arm and the oil cylinder. A plug pin is arranged on either of the knuckle arm and the oil cylinder, and a pin hole is formed in the other one of the knuckle arm and the oil cylinder. Centering induction blocks axially spaced and a front induction block are arranged on either of the inner surface of the knuckle arm and the outer surface of the oil cylinder, and centering testing pieces and a front testing piece which can induct objects correspondingly to the centering induction blocks and the front induction block respectively are arranged on the other one of the inner surface of the knuckle arm and the outer surface of the oil cylinder. When induction is conducted through the centering testing pieces and the centering induction blocks, the plug pin can be inserted and pulled relative to the pin hole. After induction is completed through the centering testing pieces and the centering induction blocks and when induction is conducted through the front testing piece and the front induction block, the oil cylinder stops extending forwards relative to the knuckle arm, and the plug pin is located in the pin hole so that the plug pin and the pin hole can be effectively and timely locked; in addition, the oil cylinder is prevented from extending forwards, the protection reliability is improved, and the structure is simple.

Description

technical field [0001] The invention relates to the technical field of booms, in particular to a structure for preventing an oil cylinder from rushing out of a jib, a method for preventing an oil cylinder from rushing out of a jib, and a boom with the structure. Background technique [0002] At present, the booms of large-tonnage cranes basically include four or five joint booms, and such booms basically adopt the telescopic method of single-cylinder latches. During the boom extension process, when the mechanism reaches the end of the last arm, the head of the oil cylinder is often very close to the sealing plate of the arm head of the last arm. Boom head, damage to structural parts and even falling objects cause casualties and serious losses. [0003] For this reason, it is necessary to add a protective device to prevent the oil cylinder from rushing out and improve the safety performance of the crane equipment. For example, in one protective measure, two vertical plates ...

AI Technical Summary

Problems solved by technology

However, in this protective measure, two vertical plates need to be welded in the head box. The opening of the original head can be used for inspection and maintenance of the internal structure of the boom. If two vertical plates are welded, people cannot Access to the interior of the barrel from the arm head for maintenance

[0004] Or, in another protective measure, a special pin ejector mechanism is mainly used, two sets of cylinder pin holes are arranged up and down, the upper and lower guide blocks are located on the upper and lower sides of the upper cylinder pin, and the induction block is arranged between the lower guide block and the lower cylinder pin. In the middle, a limit block is welded on the front end of the lower cylinder pin hole at the tail end of the last arm, and the limit block is used to block the extension of the upper mechanism of the telescopic oil cylinder. However, the structure of this protective measure is complicated, and the structure layout is limited Special requirements, resulting in higher costs

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