| 摘要 |
PURPOSE:To prevent the drag phenomenon of a friction pad by absorbing back the pressure oil in a cylinder by the force of a piston retreating spring, guiding it into a valve unit, and absorbing back a fixed quantity of the pressure oil when the pressure oil feed to the cylinder is released. CONSTITUTION:When a brake lever is operated at braking, the pressure oil from a master cylidner is returned to the chamber 42 of a pressure oil absorbing valve unit 40 through a hose, a pipe joint 71, an annular concaved groove 44, and the first port 43, and further it reaches an orifice 61 and holes 57, 58. Thereby, a valve member 50 including a valve piston 51 is displaced in the B direction by a distance (x). In synchronization with it, a caliper piston 13 is slided in the B direction against a retreating spring 30 to generate a braking force. Then, when the brake lever is disconnected to release the pressure oil, the internal oil pressure generated by the tension spring force of the retreating spring 30 of chambers 12, 45 becomes larger than the pressure in the chamber 42, and the valve member 50 is pushed back to the right. The piston 13 is forcibly drawn back in synchronization with it. |
