JPS6028628B2 - Machining method for integral double-row tapered roller bearing outer ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of machining an integral double-row tapered roller ball bearing outer ring.

In general, the inner and outer rings of bearings have a thin cylindrical shape, and the inner and outer curved surfaces are ground to high precision (shape accuracy, dimensional accuracy).
This is something that must be completed.

For this reason, this type of bearing theory was completed in the following order: outer face grinding -> inner diameter face grinding -> outer face re-grinding. In other words, the grinding heat, grinding stress, and heat treatment stress generated by the inner diameter surface grinding that is performed later are released (the heat treatment stress layer that is always applied during heat treatment is removed by grinding) on the outer diameter surface that is finished first. This is because it has an adverse effect on the roundness, etc. This point is the same in the case of an integrated double-row tapered roller bearing having a symmetrical pair of transfer surfaces A' and B' (outer diameters A and B) as shown in Fig. 1. During the running surface grinding, the outer roundness was lost, and I had to start grinding the outer surface again. That is, medium grinding → A
, B side outer diameter rough grinding, → A' side raceway surface rough grinding → B side raceway surface rough grinding → AB side outer protrusion finish grinding → A' side raceway surface finish grinding →
Finish grinding of the B' surface rolling surface has been performed, but it requires a large number of machining steps and is inefficient. On the other hand, the present applicant has previously proposed a technique for simultaneously grinding the inner and outer surfaces of an annular article such as a bearing theory.

This solves the above-mentioned problem in that the adverse effects induced by grinding the inner diameter surface (grinding heat, grinding stress, release of heat treatment stress, etc.) adversely affect the finished dimensions and accuracy of the outer diameter surface that has already been ground. This was developed in view of the above, and by grinding the inner and outer diameter surfaces at the same time, the above-mentioned negative effects that occur due to grinding and which affect the mating surface on the other side are released during grinding of the mating surface on the other side, thereby eliminating mutually negative effects. Tsutsu,
This method focuses on the fact that grinding can be performed with high accuracy and high efficiency in one grinding process. However, in the case of the integral type tapered roller bearing outer ring shown in Fig. 1, even if the inner and outer folding surfaces are ground at the same time, the above-mentioned negative problem cannot be solved because there is a pair of left and right transfer surfaces. There wasn't.

In other words, just as internal strain surface grinding has a negative effect on the finishing accuracy of the outer hook surface, which is finished first, it also has a negative effect on the finishing accuracy of the inner and outer diameter surfaces of the left side transfer surface (finished first), for example. It had been. This invention was developed in view of the above-mentioned problems. In particular, when grinding the inner and outer diameter surfaces of both raceway surfaces at the same time, the lateral surface and the outer surface of the bearing ring where the raceway surface is not formed are By carving a circumferential groove in the center of the bearing, it is possible to prevent not only the negative effects caused by grinding the inner and outer diameter surfaces, but also the negative effects caused by grinding the left and right raceway surfaces when machining the outer ring of an integrated double-row tapered roller bearing. This is what was done.

The structure of the present invention will be explained below according to the embodiment shown in FIGS. 2 and 3.

In the drawing, 1 is a packing plate, 2 and 2' are shoes, 3 is an intermediate material for the outer ring of the double-row conical roller wheel support, 4 is a grindstone for grinding the raceway surface, and 5 is a grindstone for grinding the outer surface. And in the center of the outer flea of the intermediate material 3, there is an annular ring 6 in the circumferential direction.
is provided. In the above process, as shown in FIG. 2, the outer ring is machined by first processing the A side of the intermediate material 3 using the grindstone 5, and simultaneously processes the A' side using the grindstone 4. That is, the outer diameter surface A and the inner diameter surface A' are simultaneously ground with the grindstones 5 and 4. In this case, the intermediate material 3 is supported by the shoes 2 and driven by the packing plate 1. Next, as shown in FIG. Turn the workpiece over, support the previously machined side A with shoe 2', and move the workpiece B while driving the packing plate.
Surface ``B'' is machined using grindstones 4' and 5', respectively. In other words, by simultaneously machining surface A and A', and surface B and 8, it is possible to release the internal stress of the workpiece. It has the feature that it can be machined while correcting the deformation due to It is designed to eliminate the eccentric axis of the outer surface of the workpiece material, so that the machined A side is machined so that the B side and B' side are machined. In order to prevent deformation (out of roundness) caused by the above-mentioned release of heat treatment stress on the surface and A' surface, and also to prevent the formation of a processing step between the A surface and the B surface. As explained above, the present invention is a method of machining an integral double-row conical roller ratchet outer ring having a pair of symmetrical raceway surfaces on the inner diameter surface, in which A circumferential groove along the circumferential direction of the bearing ring is cut into the intermediate material, and after grinding the inner surface, the 1 section divided by the circumferential groove is
One side's outer chamfer surface and one raceway surface are simultaneously ground, and then the other's outer chamfer surface and the other raceway surface are simultaneously ground. The negative effects of grinding heat, grinding stress, release of heat treatment stress, etc. that occur during simultaneous grinding of the inner and outer diameter surfaces are blocked by the circumferential groove, and are prevented from being transmitted to the inner and outer surfaces on the other side that were previously ground. No. 1
It will have a negative effect (release) only on the sides, and will not have a negative effect on the finishing accuracy (dimensional accuracy, shape accuracy, etc.) of the inner and outer ridges on the other side that were ground first, and will reduce the carburization depth after machining. Stress deformation due to the difference in height can be corrected very easily. Furthermore, the number of processing steps is smaller than that of the conventional method, resulting in lower processing costs and great practical advantages.

[Brief explanation of drawings]

FIG. 1 is a drawing showing the outer ring shape of a conventional integrated double-row tapered roller bearing, and FIGS. 2 and 3 are drawings showing the processing sequence of the outer ring of an integrated double-row tapered roller bearing according to the method of the present invention, respectively. It is. Turtle...Packing plate, 2,2'...Show~ 3
...Intermediate material for the outer ring of the integrated Enoki row tapered roller bearing, tortoise...
.... Grinding wheel for inner face grinding, 5... Grinding wheel for outer face grinding 6...
...Circumferential groove at the center of the outer diameter, A, B... Outer light surface "A, 8...
Inner diameter surface. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A method of machining an outer ring of an integral double-row tapered roller bearing having a symmetrical pair of raceway surfaces on the inner diameter surface, which involves forming a circumferential groove along the circumferential direction of the bearing ring in the axial center of the outer diameter surface in an intermediate material. After grinding the width surface, simultaneously grind one outer diameter surface and one raceway surface separated by the above-mentioned circumferential groove, and then grind the other outer diameter surface and the other raceway surface. A method for processing an outer ring of an integral double-row tapered roller bearing, which is characterized by simultaneously grinding.