Hydraulic cylinder having rod safety device

Abstract

A hydraulic cylinder having a rod safety device is provided, which can prevent a free falling of an arm and a bucket by fastening members when a welding part is broken to protect a cab and an operator. The hydraulic cylinder having a rod safety device which includes a cylinder rod (1) sliding within a set stroke range in a tube and composed of a rod head (1a) and a rod body (1b) joint-connected to the rod head (1a); a cover (3) connected by weld joint to one end part of the tube (2); an end cover (4) connected by weld joint to the other end part of the tube (2); a piston (5) fastened to one end part of the cylinder rod (1) to reciprocate along an inner periphery of the tube; and a connection means composed of a screw engagement part (10) formed in center parts of mutual contact surfaces of the rod head (1a) and the rod body (1b) in a shaft direction to joint-connect the rod head (1a) and the rod body (1b) by screw-engaging the rod head (1a) and the rod body (1b), and a weld joint part joint-connecting the rod head (1a) and the rod body (1b) by welding outer peripheries of the contact surfaces of the rod head (1a) and the rod body (1b).

Description

[0001] Cross References to Related Applications [0002] This application is based upon and claims the benefit of priority from Korean Patent Application No. 10-2008-0007192 filed with the Korean Intellectual Property Office on January 23, 2008, the entire contents of which are hereby incorporated by reference. technical field [0003] The present invention relates to a hydraulic cylinder with a piston rod safety device, which can improve the safety of the hydraulic cylinder by adding a joint connection device to the junction of the rod head and the rod body of the hydraulic cylinder which is jointed by welding sex. [0004] More specifically, the present invention relates to a hydraulic cylinder having a piston rod safety device, wherein a threaded engagement portion (for example, using a screw) is axially formed at a central portion of mutual contact surfaces of a rod head and a rod body of the hydraulic cylinder, and The outer surface of the joint connection portion of the...

AI Technical Summary

Problems solved by technology

[0011] However, if Image 6 As shown, in order to effectively use expensive equipment, the owner of the equipment may install selectively modified working devices (so-called "special attachments") on the bucket 7 etc. to cope with various working environments

[0012] In this case, if the welded portion 13 of the forearm cylinder 8 breaks due to welding defects or the like, mechanical free fall of the forearm 9 and bucket 7 around point 0 occurs, which causes damage to the cab 6 and damages the operator's safety. life threatening

Images