Laser pneumatic chucks are usually divided into three-jaw chucks, hydraulic chucks, soft-claw chucks and four-jaw linkage chucks.
The first and third jaw chucks determine the turning center of the workpiece according to the circumference of the clamping part of the workpiece. Generally, the parts with high precision of turning, grinding and milling are completed under the condition that the clamping accuracy of the three-jaw chuck is high. Universal indexing head, while grinding and grinding rough turning and invisible positioning accuracy required processing. A three-jaw chuck with low clamping accuracy is used; the principle of the three-jaw chuck clamping the workpiece is to use a chuck wrench to rotate any three umbrella teeth on the circumference. The three-jaw chuck used on the lathe, due to the small amount of chips, often enters the bevel gear pair and the disc-shaped shackle, causing the chuck to be loose or even stuck, and at the same time aggravating the wear of the parts and affecting normal work. Another reason for inserting the chuck chip is that the chuck flange has a high stop height, resulting in an excessive gap between the flange and the pressure cover behind the chuck;
Second, the hydraulic chuck generally consists of three parts: chuck, rotary cylinder and hydraulic station. It is a widely used chuck. Its main features are high clamping precision, durability, strong clamping force and very stable performance. Therefore, precision CNC lathes produced around the world are mainly equipped with hydraulic chucks;
Third, the soft-claw chuck can improve the positioning accuracy and save the auxiliary time of workpiece installation during the turning of large quantities of workpieces. In order to change the diameter and shape of the claw arc at any time according to actual needs, the three-claw chuck quenching claw is replaced by low carbon steel, copper or aluminum alloy claw; the positioning accuracy of the workpiece can be improved after processing. The soft jaw clamps the machined surface or soft metal, making it difficult to clamp the surface. For thin-walled workpieces, the fan-shaped jaws increase the contact area with the workpiece and reduce the deformation of the workpiece. The soft-claw chuck is suitable for fine turning of semi-finished turning and workpieces being machined, as a reference for positioning accuracy in mass production;
Correct adjustment and rotation of the soft jaw chuck is a prerequisite for ensuring the accuracy of the soft jaw chuck. The bottom of the soft claw and the positioning platform should slide with the bottom of the claw and be positioned correctly. In order to eliminate the gap, a cylinder or seal of suitable diameter must be installed in or outside the jaw. It should be installed in the position of the soft claw according to the clamping direction of the workpiece. Otherwise, the positioning accuracy of the workpiece cannot be guaranteed. When the workpiece is clamped, the cylinder should be clamped in the jaw jaws to make the jaws surface soft. When the workpiece is tightened, the ring should be installed outside the collet jaw and outside the soft gripper;
The four-claw linkage chuck is a self-centering chuck for manual four-claw machine tools. It consists of a wire, four small umbrella teeth and a pair of claws. Four small beveled teeth mesh with the dished threads. The back side of the disc-shaped thread has a planar threaded configuration, the jaws being equally mounted on the planar thread. When the small umbrella-shaped tooth is pulled by the wrench, the disk-shaped thread rotates, and the flat thread on the back of the wrench causes the claw to approach or exit the center at the same time. Since the pitch of the plane rectangular thread on the disk is equal, the four claws move at the same distance, Automatic centering function;
