Causes And Treatment Methods Of Ball Screw Clearance (1)
The application range of ball screws in the field of machine tools is more and more extensive, and the high precision of ball screws makes its assembly and debugging more and more strict. Ball screw backlash is a more common problem. If the gap is too large, it will affect the entire production process. What are the causes and treatment methods for the ball screw gap?
1. No pressure or insufficient preload.
When the ball screw is placed vertically without preloading, the nut will rotate due to its own weight, and there will be considerable clearance without preloading the screw, so it can only be used on machines with less resistance, but its main concern is positioning High precision is required. Determine the correct amount of preload and adjust the preload before shipping. Therefore, please carefully and carefully detail the operation of the equipment before ordering a ball screw.
2. Excessive torsional displacement.
The slenderness ratio of the lead screw should be controlled below 60. If the slenderness ratio is too large, the lead screw will sag under its own weight. If the heat treatment is not correct, the hardened layer is too thin, the hardness distribution is not uniform, etc., the torsional displacement will be too large.
3. Improper bearing selection.
The ball screw is usually equipped with a bevel bearing, especially a bearing with a high pressure angle is a better choice. When the ball screw is subjected to an axial load, the general deep groove ball bearing will produce a certain amount of axial backlash. So deep groove ball bearings are not suitable for this situation.
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4. Improper bearing installation.
(1) If the bearing is installed on the ball screw, but the two are not properly adhered, when they are subjected to axial load, it will cause backlash, which may be too long or too short on the shoulder of the screw.
(2) If the verticality between the bearing bearing surface and the axis of the v-tooth of the locking nut is not increased, or the parallelism of the locking nut surface in both directions is not good, the bearing will be inclined, so the v-shaped tooth of the screw shoulder lock nut will be caused. It should be processed at the same time as the bearing bearing surface to ensure the verticality. It is better if the grinding method is used.
(3) Use two lock covers and spring washers to fix the bearing to prevent the bearing from loosening during operation.
The above part is the cause of the ball screw gap and the corresponding treatment method, I hope it can be helpful to you. In the next article, the editor will continue to tell you about the reasons for the occurrence of ball screw gaps and how to deal with them. You are welcome to continue to pay attention to this website.