JPH0587133A - Needle roller bearing and manufacture thereof - Google Patents

Abstract

PURPOSE:To eliminate the generation of chip of the inner diameter surface of a bearing housing at an opening edge of an outer wheel at the time of press-in, and eliminate the positioning of a holder. CONSTITUTION:A flat plate part 2 is formed in the peripheral wall of an outer wheel 1 at an intermediate part in the axial direction, and an opening 3 is provided in this flat plate part 2. Peripheral wall parts of the outer wheel continued to both sides of the flat plate part 2 in the axial direction are formed into inclined plate parts 9, which are gradually recessed to the flat plate 2 side. A holder is formed into the one-split ring shape, which has a split part at a circumferential position same with the flat plate part 2 of the outer wheel 1, and is also formed into an outer wheel guide type. At the time of manufacturing the outer wheel 1, a thin steel plate is processed to a cylindrical shape by the deep drawing processing, and thereafter, the pressing is performed to the flat plate part 2 to punch an opening in this flat plate part 2. The inclined plate parts 9 are formed with the pressing of the flat plate part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a needle roller bearing having an opening in a peripheral wall of an outer ring and a method for manufacturing the needle roller bearing.

[0002]

2. Description of the Related Art Conventionally, in a needle roller bearing, an opening may be provided in an outer ring for supplying a lubricant or inserting a shaft engaging member. For example, in a needle roller bearing used for a bottom roller at a location reaching a false twist spindle of a textile machine, an outer ring is provided with an opening for supplying a lubricant.

FIG. 4 shows an example of a needle roller bearing having an opening in the outer ring. The outer ring 31 is a shell-shaped one obtained by deep drawing a thin steel plate, and a cage 33 holding rollers 32 is incorporated therein. The roller 32 directly contacts the shaft 37. The outer ring 31 has an opening 36 corresponding to the hole 35 of the bearing box 34, and the retainer 33 is formed as a split ring having a split portion 33a at the same circumferential position as the opening 36. These holes 35, openings 36, and split portions 33
An engaging member (not shown) that engages with the recess of the shaft 37 is inserted through a.

[0004]

In the bearing having the outer ring 31 having the shell shape as described above, the outer ring 31 is fixed to the bearing box 34 by press fitting. However, if the opening 36 is formed in the outer ring 31, for example, when the bearing is press-fitted in the direction indicated by the arrow a in the figure, the sharp edge portion 36a of the opening 36 is formed.
Therefore, the inner surface of the bearing box 34 may be cut, and the cutting dust may enter the bearing to cause an obstacle.

The outer ring 31 is made of a steel plate as described above, whereas the bearing box 34 is often made of aluminum for weight reduction or the like. Even if it is made of iron, it is not heat-treated. Therefore, the above-mentioned problem of cutting is likely to occur due to the difference in hardness. Further, the opening 36 of the outer ring 36 is generally formed by punching, and therefore the edge portion 3 is formed.
Burrs and the like may occur on 6a, which also easily causes the above-mentioned cutting problem. Therefore, the edge portion 36a is chamfered, but the number of processing steps is increased and the productivity is deteriorated.

Further, as in the example of FIG. 4, in the needle roller bearing in which the cage 33 is provided with the split portion 33a for inserting the engaging member, the opening 36 of the outer ring 33 and the circumferential position of the split portion 33a coincide with each other. However, since the retainer 33 is rotatable within the outer ring 31, the position of the split portion 33a is not fixed when the bearing is assembled. Therefore, when the engaging member is assembled through the opening 36, the position of the split portion 33 of the retainer 33 is aligned, but this alignment work must be performed through the hole 35, and therefore the workability is poor and the position is poor. There is a problem that it takes time for the matching work.

An object of the present invention is to provide a needle roller bearing in which the bearing box is not cut at the opening edge portion of the outer ring during press fitting, and the cage need not be aligned.

An object of the invention of claim 2 is to provide a manufacturing method capable of easily manufacturing the bearing having the structure of claim 1.

[0009]

In the needle roller bearing of the present invention, a flat plate portion is formed on the peripheral wall of the outer ring at an intermediate portion in the axial direction, and the flat plate portion is provided with an opening. The flat plate portion is formed so that its cross section is a chord with respect to a part of the circular arc of the outer ring circumferential shape. The peripheral wall portion of the outer ring that continues to both axial sides of the flat plate portion is formed as an inclined plate portion that is gradually recessed toward the flat plate portion. The cage arranged in the outer ring has a split ring shape having a split portion at the same circumferential position as the flat plate portion.

In the method for manufacturing a needle roller bearing according to the present invention, a process of forming a flat plate portion on the peripheral wall of a cylindrical outer ring by pressing at an intermediate portion in the axial direction and a process of forming an opening in this flat plate portion. And a process of incorporating a ring-shaped retainer into the outer ring. The flat plate portion is formed so that its cross section is a chord with respect to a part of the circular arc of the outer ring circumferential shape.

[0011]

According to the structure of the present invention, the opening of the outer ring is formed in the flat plate portion provided on the peripheral wall of the outer ring. No cutting occurs. Further, since the inclined plate portions are formed on both sides of the flat plate portion in the axial direction and project toward the inner side of the outer ring, the split portion of the retainer does not rotate inside the outer ring by hitting the flat plate portion or the inclined plate portion. Therefore, the work of aligning the cage after the assembly is unnecessary.

According to the method of the present invention, the opening is formed after pressing the flat plate portion on the peripheral wall of the cylindrical outer ring.
The opening can be easily formed by punching or the like. On both sides in the axial direction of the flat plate portion, inclined plate portions that are gradually recessed toward the flat plate portion are formed as the flat plate portion is pressed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. In this needle roller bearing A, a flat plate portion 2 is formed in an axially intermediate portion on a peripheral wall of a shell-shaped outer ring 1, and a square opening 3 is provided in the flat plate portion 2.
The flat plate portion 2 is formed so that its cross section is a chord of a part of an arc in the circumference of the outer ring 1. Outer ring peripheral wall portions continuing on both sides in the axial direction of the flat plate portion 2 are formed on the inclined plate portion 9 which is gradually recessed toward the flat plate portion 2 side. The axial width W ′ of the opening 3 is shorter than the axial width W of the flat plate portion 2, but the circumferential width may be wider than that of the flat plate portion 2.

The cage 4 is formed in a split ring shape having a split portion 4a at the same circumferential position as the flat plate portion 2 of the outer ring 1, and is of an outer ring guide type guided by the inner diameter surface of the outer ring 1. And Roller 5 held in each pocket of cage 4
Is directly abutted on the shaft 6 as shown in FIG. 3 so that the inner ring is omitted.

In manufacturing the bearing A, the outer ring 1 is obtained by processing a thin steel plate into a cylindrical shape by deep drawing, pressing the flat plate portion 2, and punching an opening 4 in the flat plate portion 2. The inclined plate plate portion 9 is formed by pressing the flat plate portion 2.

FIG. 3 shows the bearing A in use. In this bearing A, the outer ring 1 is press-fitted and fixed in the bearing housing 7.
The bearing box 7 has a radial through hole 8 in which the outer ring 1
Match the openings 3 of.

According to the bearing A having this structure, the flat plate portion 2 is formed in the outer ring 1 and the opening 3 is formed in the flat plate portion 2.
As can be seen from the figure, the edge portion 3a of the opening 3 has the bearing box 7
Does not come into contact with the inner diameter surface 7a. Therefore, there is no problem of cutting the inner diameter surface 7a of the bearing housing 7 by the edge portion 3a of the opening 3 when the outer ring 1 is press-fitted.

Further, since inclined plate portions 9 are formed on both sides of the flat plate portion 2 in the axial direction and project toward the inner side of the outer ring 1, as shown in FIG. The retainer 4 does not rotate by hitting the flat plate portion 2. That is, the cage 4 rotates only up to the position where the split portion 4a contacts the side edge 2a of the flat plate portion 2. Therefore, it is not necessary to perform the alignment for aligning the split portion 4a with the opening 3 after the cage 4 is assembled in the outer ring 1. In this way, since the troublesome positioning work which is conventionally required is not necessary, the workability of assembling the bearing A is significantly improved.

Further, according to this manufacturing method, since the outer ring 1 is formed into a cylindrical shape, the flat plate portion 2 is pressed and then the opening 3 is formed, the opening 3 can be easily processed.
Moreover, since the inclined plate portion 9 is formed along with the press work of the flat plate portion 2, it is not necessary to separately process it, and the flat plate portion 2 and the inclined plate portion 9 can be easily processed.

[0020]

According to the needle roller bearing of the present invention, the flat portion is formed at the axially intermediate portion of the peripheral wall of the outer ring, and the flat portion is provided with an opening. The part does not come into contact with the inner diameter surface of the bearing box, and the problem of cutting does not occur. Therefore, it is not necessary to chamfer the periphery of the opening, and the productivity is good. Further, since the inclined plate portions are formed on both axial sides of the flat plate portion and project toward the inner side of the outer ring, the retainer does not rotate in the outer ring, and therefore the work for aligning the retainer becomes unnecessary.

According to the manufacturing method of the present invention, since the opening is formed after pressing the flat plate portion on the peripheral wall of the outer ring, the opening can be easily formed. Moreover, the inclined plate portions on both sides of the flat plate portion are formed in accordance with the press working of the flat plate portion, and it is not necessary to separately perform the work, so that the flat plate portion and the inclined plate portion can be easily pressed. Because of these, the bearing having the structure of claim 1 can be easily manufactured.

[Brief description of drawings]

FIG. 1A is a side view showing a state of an outer ring of a needle roller bearing according to an embodiment of the present invention before opening, FIG. 1B is a plan view thereof, and FIG. It is a perspective view of the state of.

FIG. 2 is a cross-sectional view of the needle roller bearing of the same embodiment.

FIG. 3 is a cross-sectional view showing a state where the bearing of the same embodiment is incorporated in a bearing box.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

1 ... Outer ring, 2 ... Flat plate part, 3 ... Opening, 3a ... Edge part, 4
... Cage, 4a ... Split part, 5 ... Roller, 6 ... Shaft, 7 ... Bearing box, 8 ... Through hole, 9 ... Slanted plate part

Claims (2)

[Claims] 1. A flat plate portion having a cross section that serves as a chord with respect to a part of an arc of a circumferential shape of the outer ring is formed in an intermediate portion in the axial direction on the peripheral wall of the outer ring, and the flat plate portion continues to both axial sides of the flat plate portion. The peripheral wall portion is formed into an inclined plate portion that is gradually recessed toward the flat plate portion,
A needle roller bearing in which an opening is provided in the flat plate portion, and the cage arranged in the outer ring is formed in a split ring shape having a split portion at the same circumferential position as the flat plate portion. 2. A process for forming a flat plate portion, which is a chord for a circular arc of a part of the outer ring circumferential shape, in a middle portion in the axial direction on a cylindrical outer ring by press working, and an opening in this flat plate portion. A method for manufacturing a needle roller bearing, which includes a forming step and a step of incorporating a split ring-shaped cage into an outer ring.