ULTRASMALL REVOLVING WORK MACHINE

摘要

PROBLEM TO BE SOLVED: To increase the durability of a hydraulic cylinder by fitting the hydraulic cylinder having a cylinder cushion carved with a groove changed with an opening area according to the slide quantity of a rod on the outer peripheral face. SOLUTION: A cushion plunger 104 and a piston 105 are inserted into a rod 103 and fixed by a nut 106, and the tip section of the rod 103 is inserted into the tube 102 of a hydraulic cylinder 101. A housing 107 is inserted into the tube 102 and fixed on the opening end side of the tube 102. A cushion ring 110 provided with a groove 111 on the inside is arranged on the piston 105 side of the housing 107. As the rod 103 is slid, the plunger 104 is inserted into the ring 110, and the working oil flows out between the rod 103 and the housing 107 via an opening section formed by the ring 110 and the groove 111. The area of the opening section is gradually changed, thus the durability of the hydraulic cylinder 101 can be increased.