Bearing position inner hob

Abstract

The front end of a bearing position inner hob is a cutting edge, and the rear end is a hob; the role of the cutting edge is to ensure uniform processing dimensions before rolling, thereby ensuring uniform dimensions of subsequent processing; the rolling of the rear end passes through the hob, thereby improving the surface strength of a bearing position, and the processing precision of products isimproved; and cutting chips are blown away by a fan to prevent the cutting chips from adhering to the rolling surface during a rolling process, thereby affecting the smoothness and the rolling quality.

Description

technical field [0001] The invention belongs to mechanical cutting tools, in particular to a cutting tool for bearing position processing. Background technique [0002] At present, lathes and boring machines are mainly used for the processing of bearings. Whether it is a lathe or a boring machine, it is difficult to process the inner circle. The bearings and bearings adopt interference fit. The diameter is between 0.005 and 0.01mm. For example, the outer diameter of the 6204 bearing is 47mm. Then, the technical standard for the hole diameter of the 6204 bearing is between 46.99mm and 46.995mm. It is very difficult for ordinary lathes and boring machines to meet the above technical standards. Yes, and the processing size is related to the tool and the speed of the cutting tool. If the speed is fast, the size will become larger under the same conditions, and the size will become smaller when the cutting speed is slow. In order to achieve the processing accuracy, the usual prac...

AI Technical Summary

Problems solved by technology

[0002] At present, lathes and boring machines are mainly used for the processing of bearings. Whether it is a lathe or a boring machine, it is difficult to process the inner circle. The bearings and bearings adopt interference fit. The diameter is between 0.005 and 0.01mm. For example, the outer diameter of the 6204 bearing is 47mm. Then, the technical standard for the hole diameter of the 6204 bearing is between 46.99mm and 46.995mm. It is very difficult for ordinary lathes and boring machines to meet the above technical standards. Yes, and the processing size is related to the tool and the speed of the cutting tool. If the speed is fast, the size will become larger under the same conditions, and the size will become smaller when the cutting speed is slow. In order to achieve the processing accuracy, the usual practice of mechanical workers It is multiple processing and multiple measuring scales. In this way, the machining allowance of the last few knives is often very small. Even if the size of the processed product meets the requirements, because the inner diameter micrometer will not measure with great effort, but the actual size is not. Stable, the surface hardness of the workpiece size is not enough, and the finish is difficult to meet the design requirements. This kind of product is not a big problem when it first leaves the factory, but after a period of use, the bearings and bearing positions are loose, and the looseness of the bearings and bearing positions is further increased. The shaking of the main shaft will make the situation worse and worse. An important factor for the unstable quality of mechanical products is the unstable processing quality of the bearing. As a result, the rigidity of the bearing material is reduced. At the same time, the degree of heat generation of the outer ring of the bearing is much higher than that of the bearing position, because the bearing position itself does not generate heat, and the heat is transferred to the bearing position through the bearing. In addition, the volume of the bearing seat is also larger than that of the bearing. The speed is not as good as that of the bearing, and the above process will also deteriorate the fit between the bearing and the bearing housing. However, the heat will cause the interference value of the bearing's own ball and the outer ring to become smaller, which is conducive to the rotation of the bearing. In addition, the material of the bearing housing itself has a certain degree of ductility. Therefore, an appropriate amount of heat will not affect the performance of the bearing. Moreover, after the interference fit is less than 0.003mm, the bearing and the bearing position are easy to loosen, and there are also problems. In the machinery industry, almost all machinery involves bearings and bearing seats. However, through ordinary lathes and boring machines, whether it is manual processing or CNC processing, the processing size of the bearing position is far less important than the processing of the spindle bearing position. From the perspective of mechanical principles, the deformation of the inner ring of the bearing and the outer ring Deformation. Under the same conditions, the deformation of the outer ring is more serious. Usually, the interference value between the inner diameter of the bearing and the main shaft is 0.01mm to 0.02mm, which is higher than the interference fit value between the outer ring and the bearing position. , the fit of the outer ring of the bearing has a greater impact on the service life of the bearing than the fit of the inner ring

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