SINGLE-CYLINDER PLUG PIN TYPE TELESCOPIC ARM, TELESCOPIC METHOD THEREOF AND CRANE HAVING TELESCOPIC ARM

摘要

The present invention relates to a single-cylinder plug pin type telescopic arm, a crane and a telescopic method thereof. The single-cylinder plug pin type telescopic arm includes a basic arm and at least one telescopic arm sleeved in the basic arm, wherein coaxial center holes are formed in the tails of the telescopic arms, and a telescopic oil cylinder is arranged in the center holes; the telescopic oil cylinder includes a cylinder rod and a cylinder barrel, at least two cylinder heads are fixedly sleeved on the outer side of the cylinder barrel in the longitudinal direction, and at least three arm pin holes are formed in each of the basic arm and the telescopic arms in the longitudinal direction. The single-cylinder plug pin type telescopic arm provided by the present invention adopts one telescopic oil cylinder and at least two cylinder heads, each cylinder head is adapted to lock and unlock the telescopic oil cylinder and any telescopic arm, the telescopic arms are extended out or retracted in a relay transmission manner to achieve the extension and retraction of the single-cylinder plug pin type telescopic arm, the length of the oil cylinder is shortened, the cylinder diameter and the rod diameter of the oil cylinder are decreased, the cost of the oil cylinder is lowered, the upperstructure weight is reduced, the lifting capacity is improved, and there are more crane design spaces.