WO2014088060A1

WO2014088060A1 - Method for producing shell-type needle bearing

Info

Publication number: WO2014088060A1
Application number: PCT/JP2013/082679
Authority: WO
Inventors: 近藤　豊
Original assignee: 日本精工株式会社
Priority date: 2012-12-06
Filing date: 2013-12-05
Publication date: 2014-06-12
Also published as: JP2016029286A

Abstract

The present invention is a method for assembling a shell-type needle bearing (10) that does not require a plating step as in conventional techniques by means of assembling a needle (12) and holders (13, 18) after forming and heat-treating both flange sections (11b, 11c) of a shell outer race (11) by using diameter-reducible holders. Also, it is possible to use a resin material as the material for the holders (13, 18) as the holders (13, 18) do not incur the effect of heat resulting from the heat treatment.

Description

Method for manufacturing shell needle bearing

The present invention relates to a method for manufacturing a needle bearing, and more particularly, to a method for manufacturing a shell-type needle bearing used for a rotation support portion of various mechanical devices.

In recent years, in automatic transmissions of automobiles, shell-type needle bearings having the same cross-sectional height are used in place of sliding bearings (bushes) at sites that receive radial loads. As shown in FIG. 9, the shell-type needle bearing 100 can be rolled along a raceway surface 101a, a shell outer ring 101 having a raceway surface 101a on an inner peripheral surface and a pair of

flange portions

101b and 101c on both ends. A plurality of needles 102 arranged in the shell outer ring 101 and a holder 103 having a plurality of pockets for holding the plurality of needles 102 are provided.

As a conventional manufacturing method of such a shell-type needle bearing 100, first, as a forming process of the shell outer ring 101, a deep cold drawing from a normal cold-rolled steel sheet (for example, a low carbon steel such as SPCC) into a cup shape is performed. One flange portion 101b is formed by punching. A plating process such as copper plating is performed on the edge of the shell outer ring 101 on the axial opening side, and a heat treatment such as carburizing or carbonitriding is performed. Thereafter, the needle 102 and the cage 103 are incorporated into the shell outer ring 101 from which the plating has been removed, and the flange portion 101c is formed by bending the edge of the shell outer ring 101 on the opening side in the axial direction. The bearing 100 is manufactured.

However, when the pressing process is followed by the plating process, the heat treatment process, the plating removal process, and the assembly / pressing process, it is difficult to set these processes on the same line. There are problems in that the number of processes is large, processing time is required, equipment costs are high, and transportation between the processes must be taken into consideration. Furthermore, there has been a problem that various chemical substances must be used for removing the plating.

Therefore, in order to omit the plating process, Patent Document 1 describes a hot curl technique in which bending is performed while heating the flange portion 101c at a high frequency.
Patent Document 2 describes a technique in which a shell needle bearing is assembled without performing heat treatment, and finally, the assembled shell needle bearing is entirely nitrided.

Japanese Laid-Open Patent Publication No. 11-303863 Japanese Laid-Open Patent Publication No. 2002-139067

However, in the techniques of the cited references 1 and 2, since the heat treatment is performed after the component parts are incorporated in the shell outer ring 101, it is not possible to use a resin cage that is weak against heat. For this reason, when using a resin cage, a manufacturing method including a plating step as in the prior art has to be selected.

This invention is made | formed in view of the said situation, The objective is to provide the manufacturing method of the shell type needle bearing using the resin retainer which can be manufactured with the manufacturing method which does not require a plating process. .

The above object of the present invention is achieved by the following configurations.
(1) a shell outer ring having a raceway surface on an inner peripheral surface and a pair of inward flange portions on both ends;
A plurality of needles arranged in the shell outer ring so as to be able to roll along the raceway surface of the shell outer ring;
A retainer having a plurality of pockets for holding the plurality of needles, and a manufacturing method of a shell-type needle bearing comprising:
The cage can be reduced in diameter,
After both flange portions of the shell outer ring are molded and heat-treated, the cage is reduced in diameter and inserted into the shell outer ring, and then the plurality of needles are inserted into pockets of the cage. A method for manufacturing a shell needle bearing.
(2) a shell outer ring having a raceway surface on an inner peripheral surface and a pair of inward flange portions on both ends;
A plurality of needles arranged in the shell outer ring so as to be able to roll along the raceway surface of the shell outer ring;
A retainer having a plurality of pockets for holding the plurality of needles, and a manufacturing method of a shell-type needle bearing comprising:
The cage can be reduced in diameter,
After forming both flange portions of the shell outer ring and applying heat treatment, a unit incorporating the plurality of needles in the cage pocket is inserted into the shell outer ring by reducing the diameter of the cage. A method for manufacturing a shell-type needle bearing.
(3) The cage includes a pair of rim portions arranged coaxially with each other, and a plurality of column portions that connect the pair of rim portions in the axial direction,
Each of the pair of rim portions is constituted by a plurality of arc-shaped portions,
A plurality of cuts are formed in the same direction in the circumferential direction in each rim portion between each end of the arc-shaped portion adjacent in the circumferential direction,
A plurality of elastic deformation portions that contract or extend in the circumferential direction are provided in the circumferential direction between the column portions adjacent in the circumferential direction in which the cut is formed,
The elastically deforming portion has each end portion of the arc-shaped portion adjacent in the circumferential direction as a base end portion and extends inward in the axial direction from each end portion, and the extended portion is in the circumferential direction. Having a pair of elastically deforming pieces to be connected at
The pair of elastic deformation pieces have the same shape,
The method for manufacturing a shell-type needle bearing according to (1) or (2), wherein the elastically deforming portion is formed symmetrically with respect to an axially intermediate portion.

According to the method for manufacturing a shell-type needle bearing of the present invention, since the cage and needle are incorporated after both flange portions of the shell outer ring are molded and heat-treated, the plating process as in the prior art is unnecessary, and the cage Is not affected by the heat treatment, so that a resin can be used as a material for the cage.

A sectional view of a shell type needle bearing concerning an embodiment of the present invention. Partially enlarged plan view of the cage of FIG. FIG. 2 is an axial sectional view of the cage of FIG. 1. The principal part enlarged plan view of FIG. Explanatory drawing which shows the deformation | transformation to the radial direction of the elastic deformation part of FIG. (A) shows the sectional view of a cage before elastic deformation, and a shell, (b) is a side view seen from the V direction of (a). (A) shows the cage after elastic deformation, and a sectional view of the shell, (b) is a side view seen from the VI direction of (a). The axial sectional view of another cage. Sectional drawing which shows the conventional shell type needle bearing.

Hereinafter, shell-type needle bearings according to embodiments of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, the shell needle bearing 10 includes a shell outer ring 11 as a bearing ring having a raceway surface 11 a on an inner peripheral surface and a pair of

inward flange portions

11 b and 11 c on both ends, and a shell outer ring 11. A plurality of needles 12 arranged in the shell outer ring 11 and a cage 13 having a plurality of pockets 14 for holding the plurality of needles 12 so as to be freely rollable along the raceway surface 11a. A shaft (or inner ring member) (not shown) is rotatably supported.

The shell outer ring 11 is formed by subjecting a cold-rolled steel sheet (for example, low carbon steel such as SPCC) or the like to plastic processing such as drawing, so that a pair of

flange portions

11b and 11c are bent at both ends of the entire cylindrical shape. Is formed. The shell outer ring 11 is hardened by heat treatment by carburizing or carbonitriding.

The shell outer ring 11 is formed with

flange portions

11b and 11c before the needle 12 and the cage 13 are assembled, and is further cured by heat treatment. Therefore, unlike the flange 101c of the conventional shell outer ring 101, the

flanges

11b and 11c can be formed in the same shape so that they can be easily bent later. Can be eliminated. Further, it is possible to form by cutting from a thick plate instead of plastic processing of a thin plate.

As shown in FIG. 2, the retainer 13 includes a pair of

rim portions

15 and 15 arranged coaxially with each other, and a plurality of column portions 16 that connect the pair of

rim portions

15 and 15 in the axial direction. The pair of

rim portions

15 and 15 are respectively configured by a plurality (four in this embodiment) of arc-shaped portions 15a. Between the

end portions

15b and 15b of the arc-shaped portion 15a adjacent to each other in the circumferential direction, a plurality of cuts 15c are formed in the

rim portions

15 and 15 with the same phase in the circumferential direction. As the number of cuts 15c increases, the number of needles 12 decreases, so the number of cuts 15c is preferably 2-6.

The cage 13 is provided with an elastic deformation portion 17 that contracts the cage 13 (cut 15c) in the circumferential direction between the

column portions

16 and 16 adjacent to each other in the circumferential direction in which the cut 15c is formed. A plurality are provided in the direction.

A rectangular space that is surrounded by four sides by the circumferential side surfaces of the

column parts

16 and 16 that are adjacent to each other in the circumferential direction without sandwiching the elastic deformation part 17 and the inner side surfaces of the pair of

rim parts

15 and 15 that face each other. The portions are

pockets

14 and 14, respectively. And as shown in FIG. 3, the inner diameter

side latching protrusions

16a, 16a are provided on the inner end portions in the diameter direction of the cage 13 on both sides in the circumferential direction of the

pillars

16, 16, respectively. 16 is formed over the entire length.

The elastically deformable portion 17 extends inward in the axial direction from each of the end portions 15b with the

end portions

15b, 15b of the arc-shaped

portions

15a, 15a adjacent in the circumferential direction as base end portions. It has a pair of

elastic deformation pieces

17a and 17a which connect the done part in the circumference direction. The pair of

elastic deformation pieces

17 a and 17 a have the same shape, and the elastic deformation portion 17 is formed symmetrically with respect to the axial intermediate portion C of the cage 13.

As shown in FIG. 4 in an enlarged manner, the elastic deformation piece 17a is composed of a plurality of arcs 17a1, 17a2, 17a3 each having a radius of curvature R1 to R3. However, the elastic deformation piece 17a may be configured by a single arc.

Further, the axial width w1 of each end portion 15b of the arcuate portion 15a serving as the base end portion of the elastic deformation portion 17 is equal to or greater than the axial width w2 of the arcuate portion 15a in consideration of the strength of the base end portion. Preferably there is. Further, it is preferable that the curvature of the arc surface formed on the inner side surface in the axial direction of the base end portion is large (the curvature radius r is small).

Further, as shown in FIG. 5, the radial thickness h of the elastic deformation piece 17a is set to be thicker than the width w3 of the elastic deformation piece 17a. Can be suppressed.

Next, a method for incorporating the cage 13 having the above-described configuration into the shell outer ring 11 will be described.

6 (a) is a cross-sectional view of the cage 13 and the shell outer ring 11 before elastic deformation, and FIG. 6 (b) is a side view seen from the V direction of FIG. 6 (a). 7A is a cross-sectional view of the cage 13 and the shell outer ring 11 after elastic deformation, and FIG. 7B is a side view seen from the VI direction of FIG. 7A.

The outer diameter φD1n of the cage 13 is larger than the inner diameter φD2 (hereinafter referred to as the flange inner diameter) of the pair of

inward flange portions

11b and 11c of the shell outer ring 11 (φD1n> φD2). The cage 13 can deform the elastic deformation portion 17 to narrow the circumferential distance L1 (see FIG. 2) of the cut 15c, and can shrink the cage 13 in the circumferential direction. Thereby, as shown in FIG. 6, the cage 13 can be reduced in diameter to an outer diameter φD1s smaller than the flange inner diameter φD2 of the shell outer ring 11 (φD2> φD1s). Here, the relationship between the outer peripheral length of the cage 13, the sum of the circumferential distances L1 of the cuts 15c, and the inner peripheral lengths of the

inward flange portions

11b and 11c of the shell outer ring 11 is substantially as follows: Become.
π · φD1n−L1 × (number of cuts) <π · φD2

The movable range, that is, the deformation amount of the elastic deformation piece 17a can be arbitrarily set by the axial distance L3 (see FIG. 3) between the pair of

elastic deformation pieces

17a and 17a and the circumferential distance L1 of the cut 15c. It becomes. However, the circumferential distance L1 of the cut 15c before elastic deformation is such that the column 16 and the elastic deformation piece 17a before the elastic deformation do not contact each other before the cut 15c disappears. It is set smaller than the sum of the circumferential distances L2 and L2 (L1 <2 × L2).

The diameter of the cage 13 is reduced until it becomes smaller than the flange inner diameter φD2 of the shell outer ring 11, and the cage 13 is inserted into the shell outer ring 11. After the insertion, the cage 13 is accommodated in the shell outer ring 11 when the elastic deformation portion 17 is restored.

Then, the needle 12 is inserted into the

pockets

14 and 14 of the cage 13 from the inner diameter side of the cage 13. In the insertion operation, the

column portions

16 and 16 partitioning the circumferential sides of the

pockets

14 and 14 and the inner diameter side locking projections 16a formed on the side surfaces of the

column portions

16 and 16 are elastically deformed. Meanwhile, each needle 12 is pushed into each

pocket

14, 14.

Since the width Wp extending in the circumferential direction of the pocket 14 at the portion removed from the locking protrusion 16a is larger than the outer diameter φDk of the needle 12 (Wp> φDk), the needle 12 is held in each pocket 14 The needles 12 can roll with a light force in the pockets 14. Further, the distance Wi between the distal end edges of the pair of inner diameter

side locking projections

16a, 16a existing in the inner diameter side opening of each

pocket

14, 14 is smaller than the outer diameter φDk of each needle 12. (ΦDk <Wi). Therefore, the needles 12 held in the

pockets

14 and 14 are not inadvertently dropped from the

pockets

14 and 14.

Next, another method for assembling the shell type needle bearing will be described. The components used for the assembly by this different method and the components used for the assembly described above differ only in the cage 18.

As shown in FIG. 3, the retainer 13 has inner

side locking projections

16 a and 16 a at the inner end portions in the diameter direction of the retainer 13 on both circumferential sides of the

pillars

16 and 16. It is formed over the entire length of the

column parts

16 and 16. On the other hand, as shown in FIG. 8, the retainer 18 used in this assembling method includes outer diameter

side locking projections

16b and 16b on the outer end in addition to the inner diameter

side locking projections

16a and 16a. It is formed over the entire length of the

portions

16 and 16. Other configurations are the same as those of the cage 13 described above.

First, a plurality of

needles

12 and 12 are inserted into the

pockets

14 and 14 from the inner diameter side or outer diameter side of the cage 18. At the time of this insertion work, the

column portions

16 and 16 partitioning both sides in the circumferential direction of the

pockets

column portions

16 and 16, Each needle 12 is pushed into each of the

pockets

14 and 14 while elastically deforming the radial side locking projection 16b. Since the width Wp extending in the circumferential direction of each

pocket

14, 14 at the part removed from each locking

projection

16 a, 16 b is larger than the outer diameter φDk of each needle 12 (Wp> φDk), In the state where the needles 12 are held, the needles 12 can roll with a light force in the pockets 14. In addition, the distance Wi between the distal end edges of the pair of inner diameter

side locking projections

16a, 16a existing in the inner diameter side opening portions of the

pockets

14, 14 in a free state and the pair of outer surfaces existing in the outer diameter side opening portions. The distance Wo in the free state between the distal end edges of the radial

side locking projections

16b, 16b is smaller than the outer diameter φDk of each needle 12 (φDk <Wi, φDk <Wo). Therefore, the needles 12 held in the

pockets

14 and 14 are not inadvertently dropped from the

pockets

14 and 14.

Thus, after the plurality of

needles

12 and 12 are first assembled in the cage 18, the diameter is reduced in the same manner as the cage 13 described above and incorporated in the shell outer ring 11. Therefore, since the sub-assembly product in which the plurality of

needles

12 and 12 are incorporated in the cage 18 can be handled as a unit, the degree of freedom in the assembly process can be increased.

Here, the

cages

13 and 18 are made of resin, and polyamides (nylon resin) such as aromatic polyamide (aromatic PA), polyamide 46, polyamide 6 and polyamide 66, polyphenylene sulfide (PPS), polyether ether ketone. Fluorine resins such as (PEEK), polyacetal (POM), and polytetrafluoroethylene (PTFE) can be used. Moreover, what mixed reinforcing agents, such as glass fiber and carbon fiber, with these resin can also be used conveniently. More preferably, polyamide resin is mixed with glass fiber or carbon fiber in an amount of 5 to 30% by weight, and the flexural modulus is set to 2000 to 5000 MPa. Within this range, the deformable portion can be more suitably deformed and have the necessary rigidity.

In the present embodiment, the inner diameter side locking projection 16a and the outer diameter side locking projection 16b are formed over the entire length of each of the

column portions

16 and 16, respectively, but only in a range narrower than the total length. It may be provided or may be divided into a plurality of parts.

As described above, according to the shell-type needle bearing 10 of the present embodiment, the

cages

13 and 18 are provided with a plurality of elastic deformation portions 17 that are contracted in the circumferential direction. Since the portion 17 is formed symmetrically with respect to the axial middle portion C, plastic deformation is prevented, it has sufficient strength against axial twisting, and a sufficient amount of deformation is ensured. However, the

cages

13 and 18 that can be contracted in the circumferential direction can be provided. Further, the elastic deformation portion 17 allows the movement of the needle 12 to be appropriately allowed, and can prevent fretting.

Further, the pair of

rim portions

15 and 15 are configured by a plurality of arc-shaped portions 15a, and the pair of

rim portions

15 and 15 includes a plurality of

rim portions

15 and 15 between a plurality of end portions 15b of the arc-shaped portions 15a adjacent in the circumferential direction. The cuts 15c are formed in the same phase in the circumferential direction, and the elastic deformation portions 17 extend inward in the axial direction from the respective end portions 15b of the adjacent arc-shaped portions 15a, and the extended portions are arranged in the circumferential direction. Has a pair of elastically

deformable pieces

17a, 17a connected to each other. Thereby, the elastic deformation part 17 symmetrical with respect to the axial direction intermediate part C can be formed.

Further, the elastic deformation portion 17 is formed between the

column portions

16 and 16 adjacent in the circumferential direction, and the circumferential distance L1 of the cut 15c is the circumferential direction between the adjacent column portion 16 and the elastic deformation piece 17a. Since the distance L2 is smaller than the sum of the distances L2, the column part 16 and the elastic deformation piece 17a do not contact each other before the cut 15c disappears when contracted in the circumferential direction, and a sufficient amount of deformation can be ensured. .

In addition, since the

cages

13 and 18 and the needle 12 are incorporated after the

flange portions

11b and 11c of the shell outer ring 11 are molded and heat-treated, the plating process as in the prior art is unnecessary, and the cage is heated by heat treatment. Since it is not affected, resin can be used as the material of the

cages

13 and 18.

Note that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like can be made as appropriate.

This application is based on Japanese Patent Application No. 2012-267411 filed on Dec. 6, 2012, the contents of which are incorporated herein by reference.

As described above, according to the manufacturing method of the shell type needle bearing of the present invention, the cage and needle are incorporated after both flange portions of the shell outer ring are molded and heat-treated, so that the plating process as in the prior art is unnecessary. In addition, the cage is not affected by the heat treatment. Therefore, since a resin can be used as the material of the cage, it can be suitably employed as a method for manufacturing a shell-type needle bearing used for the rotation support portion of various mechanical devices.

DESCRIPTION OF SYMBOLS 10 Shell type needle bearing 11 Shell outer ring | wheel

11a Raceway surface

11b Flange part

11c Flange part 12 Needle 13 Cage 14 Pocket 15 Rim part 15a Arc-shaped part 15b End part 15c Break 16 Column part 16a Inner diameter side locking protrusion 16b Outer diameter side Locking projection 17 Elastic deformation part 17a Elastic deformation piece 17a1 Arc 17a2 Arc 17a3 Arc 18 Cage 100 Shell-type needle bearing 101 Shell outer ring 101a Track surface

101b Flange part

101c Flange part 102 Needle 103 Cage

Claims

A shell outer ring having a raceway surface on the inner peripheral surface and a pair of inward flange portions on both ends;
A plurality of needles arranged in the shell outer ring so as to be able to roll along the raceway surface of the shell outer ring;
A retainer having a plurality of pockets for holding the plurality of needles, and a manufacturing method of a shell-type needle bearing comprising:
The cage can be reduced in diameter,
After both flange portions of the shell outer ring are molded and heat-treated, the cage is reduced in diameter and inserted into the shell outer ring, and then the plurality of needles are inserted into pockets of the cage. A method for manufacturing a shell needle bearing.
A shell outer ring having a raceway surface on the inner peripheral surface and a pair of inward flange portions on both ends;
A plurality of needles arranged in the shell outer ring so as to be able to roll along the raceway surface of the shell outer ring;
A retainer having a plurality of pockets for holding the plurality of needles, and a manufacturing method of a shell-type needle bearing comprising:
The cage can be reduced in diameter,
After forming both flange portions of the shell outer ring and performing heat treatment, a unit incorporating the plurality of needles in the pocket of the cage is inserted into the shell outer ring by reducing the diameter of the cage. A method for manufacturing a shell needle bearing.
The cage includes a pair of rim portions arranged coaxially with each other, and a plurality of column portions that connect the pair of rim portions in the axial direction,
Each of the pair of rim portions is constituted by a plurality of arc-shaped portions,
A plurality of cuts are formed in the same direction in the circumferential direction in each rim portion between the end portions of the arc-shaped portions adjacent in the circumferential direction,
A plurality of elastic deformation portions that contract or extend in the circumferential direction are provided in the circumferential direction between the column portions adjacent in the circumferential direction in which the cut is formed,
The elastically deforming portion has each end portion of the arc-shaped portion adjacent in the circumferential direction as a base end portion and extends inward in the axial direction from each end portion, and the extended portion is in the circumferential direction. Having a pair of elastically deforming pieces to be connected at
The pair of elastic deformation pieces have the same shape,
The method for manufacturing a shell-type needle bearing according to claim 1 or 2, wherein the elastically deforming portion is formed symmetrically with respect to the axially intermediate portion.