Internal and external clamping method and device of thin-wall tubular part during rotary processing

An internal and external clamping device comprising a first pull rod, a second pull rod, an inner cylinder, an outer sleeve, a wedge-shaped sleeve, a hook, a clamping cylinder, a threaded push rod, a support claw ring, a spring, a washer, a nut, a support block, a rotary shaft, a jacket, a flange bush and a support plate;

• the first pull rod and the second pull rod are connected with each other and respectively provided with a flange;
• the second pull rod is connected with the inner cylinder, and connected at the other end with the threaded push rod, the first pull rod being disposed at one end of the second pull rod, the inner cylinder being provided on the outer periphery with the outer sleeve;
• the inner cylinder is provided on the outer periphery in the ring direction with a plurality of guide key grooves, which are provided inside with guide keys;
• the outer sleeve is provided with a guide groove on the inner cylindrical surface corresponding to the periphery of the guide key groove of the inner cylinder, and connected at one end to a main shaft of a machine tool and at the other end to the jacket;
• the wedge-shaped sleeve is connected at one end to the inner cylinder, and at the other end to the clamping cylinder, the other end of which is arranged in the wedge-shaped surface of the jacket;
• the wedge-shaped sleeve is provided on the outer peripheral surface with a plurality of hooks at intervals, which are provided with steps at the right end;
• the clamping cylinder is provided on both sides of the outer wall with a wedge-shaped surface having the same inclination angle as the inner side of one end of the wedge-shaped sleeve and the inner side of the jacket;
• the clamping cylinder is provided on the outer circumference with an annular groove, which is connected to the step on the hook;
• the clamping cylinder is provided with a plurality of grooves at intervals in the circumferential direction from both ends to the middle;
• a plurality of support blocks are spaced to form an annular structure around the flange bush;
• the middle portion of each support block is provided with a through hole;
• a support claw is provided between every two support blocks, and the side surface of the support claw is provided with the through hole;
• a rotary shaft penetrates through the through holes in the support claws and the support blocks;
• a plurality of rotary shafts are spaced to form an annular structure around the flange bush;
• a flange bush, arranged between the inner cylinder and the second pull rod, is provided at one end with a flange, which is provided at one end face with grooves identical to the support blocks in number and shape, with the support block fixed in the groove of the flange of the flange bush;
• the other end of the flange bush is connected through the flange to the support plate, which is connected to the outer sleeve;
• a round step is arranged on the threaded push rod, on which the spring, the washer and the nut are sleeved;
• a plurality of support claws are spaced to form a support claw ring having the annular structure;
• each support claw is formed by connecting the front end, the rear end, and the bottom;
• the outer surface of the front end, used to press against the inner wall of the thin-wall tubular part, is an arc surface with the same curvature as the inner wall of the thin-wall tubular part;
• the spring is connected at one end to the bottom of the support claw ring, and at the other end to the washer, with a nut arranged outside the washer;
• the support claw ring is placed inside the clamping cylinder, and the thin-wall tubular part is placed between the outer surface of the support claw ring and the inner surface of the clamping cylinder.