HYDRAULIC AUTOMATIC TENSIONER

摘要

A hydraulic automatic tensioner having a reduced axial length. A sleeve (13) is assembled into a cylinder (11) filled with hydraulic oil, and a flange (14) provided at the lower end of the sleeve (13) is supported by a step (15) provided in the lower part of the internal periphery of the cylinder (11). A rod (19) is slidably installed in the sleeve (13) to partition the inside of the cylinder (11) into a pressure chamber (20) and a reservoir chamber (21), and the rod (19) is urged by a return spring (24) in the direction to increase the volume of the pressure chamber (20). A circular arc path (30) interconnecting the pressure chamber (20) and the reservoir chamber (21) is formed in the flange (14), the path (30) is adapted to be opened and closed by a check valve (31), and thus the hydraulic automatic tensioner has a reduced axial length.