Nov. 03, 2019
When the lathe three-jaw chuck is used for a long time, the same shaft reduction and bell mouth phenomenon will occur, which directly affects the machining accuracy and the reliability of the clamping. Practice has proved that the following methods can be used to correct the accuracy and improve the reliability of the clamping. The method is simple and practical, and the effect is remarkable. You may wish to try it.
Taking this positive claw chuck as an example, first clamp a round rod of appropriate diameter with an external clamp, start the machine tool, and turn the outer circle portion of the claw. Then, the inner ring is used to clamp a ring member, the machine tool is started, and the inner and inner ends of the claw are turned. Obviously, this can significantly improve the same axis of the internal circle of the claw after machining and the spindle of the machine tool and eliminate the phenomenon of the bell mouth, and obtain higher precision to achieve the purpose of correction.
The specific application fashion should pay attention to the following points: The outer circle of the round bar and the inner circle of the ring must be processed in advance and have a certain precision. Moreover, the inner diameter of the torus should not be too small, so that the concave surface of the claw surface is deep and deep, and it is easy to damage the surface of the workpiece when clamping a large-diameter workpiece, which needs attention.
Because there is inevitably a gap between the claw and the chute of the chuck body, the direction of the force of the claw during the correction is exactly opposite to the direction of the force during the actual operation, so that the chuck after the correction will not only have a horn when used. Mouth phenomenon. Therefore, when the correction is made, the inner circle of the claw should be pre-machined into a tapered taper (the inner and outer small). The taper value can be determined by experiment, which is the key to success.
Due to the high hardness of the jaws, it is also interrupted cutting. Therefore, the cutting depth and the amount of cutting are small, and the cutting speed is not very high. The tool material is the best to use hard alloy. If it can install a small power head on the carriage, the grinding wheel correction is better.
The first step is to cut the external circle of the jaws in order to establish a good benchmark to improve the correction accuracy. This step is best not to save.
The method can also be used to correct the error caused by improper installation or other reasons for the new three-claw, thereby improving the machining accuracy. The same principle can be used for the correction of the reverse claw.
