In the traditional inner hole machining of cylinder type workpieces, most of the three-jaw chucks are used to clamp the workpiece. This chuck does not need to be designed by itself; however, since the feeding action of the brake master cylinder processing machine is the fixture The workpiece is reciprocated together, and the grinding head is rotated in the cylinder bore to complete the main motion, and the workpiece cannot be tightened using the three-jaw chuck. If the clamp power unit is hydraulically or pneumatically clamped, the space occupied by the clamp is relatively large and maintenance is inconvenient. To this end, a set of special fixtures is designed. This set of fixtures takes up a small space, is flexible, efficient and fast, and improves the overall economy and coordination of the machine tool. The fixture precursor and the rear body together position the workpiece axially, and the position of the clamp precursor can be adjusted to accommodate workpieces of different lengths; the left stopper acts as a radial positioning and clamping of the workpiece to eliminate workpiece processing. Due to the torque generated by the friction during the process, the position of the stopper can be adjusted within a certain range to accommodate different sizes of workpieces. During the machining of the workpiece, the rear body of the clamp performs the reciprocating feed motion together with the workpiece of the clamp and the workpiece. The specific structure of the brake cylinder processing equipment is composed of the clamp rear body, the baffle, the workpiece, the clamp precursor, the stopper, the connecting rod and the stopper. The three-dimensional software Pro/E is used to model these components. After the component solid model is built, the assembled module of the Pro/E software is used to assemble the built-up fixture component solid model to obtain a completed concrete model. (Finish)