Telescopic boom with buckling-resistant multi-stage, fixed hydraulic cylinder

摘要

The present invention relates to a multistage array telephoto boom consisting of a stationary hydraulic cylinder that prevents side buckling of a cylinder, wherein the cylinder is supported by a rigid telescopic boom member. Several support devices are provided for this purpose, one part of which is fixed to at least one unit of the multistage hydraulic cylinder and the other part of the support device to the inner wall of at least one telephoto member. The two parts of the support unit are continuously engaged with each other so that the buckling of the hydraulic cylinder is prevented at all positions of the telescopic boom. Moreover, the present invention ensures that the telescope is fully extended by starting with the cylinder section with the largest cross section and ensuring the proper size of successive connection in the order of the cylinders with the smaller cross section, and the process of folding the telescopic boom is done in this reverse order. The present invention has the advantage of supplying the hydraulic fluid to the cylinder chamber of the fully opened cylinder portion by blocking the check valves of all the cylinder portions so that the cylinder portions are not opened for a while, the check valve is opened only when the cylinder portion is fully extended.