JP4123883B2 - Roller bearing manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a roller bearing.
[0002]
[Prior art]
As a conventional shell-type needle roller bearing, there is one as shown in FIG. 7 (see, for example, Patent Document 1). In the figure, reference numeral 81 denotes an entire shell-shaped needle roller bearing, 82 denotes a shell-shaped outer ring, and 83 denotes a plurality of needle rollers.
[0003]
The outer ring 82 is manufactured by pressing a single metal plate, and radially inwardly bent pieces 82b and 82c are provided on both axial sides of the cylindrical portion 82a. The bent pieces 82b and 82c are bent at an angle of approximately 90 degrees with respect to the cylindrical portion 82a.
[0004]
In the shell-shaped outer ring 82, the first bent piece 82b is set slightly thicker than the cylindrical portion 82a. However, the second bent piece 82c and the cylindrical portion 82a are close to the second bent piece 82c. Is set to be thinner than the thickness of the raceway surface region of the cylindrical portion 82a. The reason why the second bent piece 82c is made thin in this way is that the second bent piece 82c is bent after the outer ring 82 is drawn into a bottomed cylindrical shape by pressing. This is to facilitate post-bending work.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-106576 (FIGS. 7, 8, and 9)
[0006]
[Problems to be solved by the invention]
If the thin second bent piece 82c is slightly deformed obliquely inward in the axial direction for some reason, the needle roller bearing 81 is deformed when the needle roller 83 is displaced in the axial direction. The end surface of the needle roller 83 interferes with the inner corner of the tip of the second bent piece 82c and hits the edge. When such edge contact occurs, there is a risk of oil film breakage and seizure.
[0007]
[Means for Solving the Problems]
The method of manufacturing a roller bearing according to the present invention includes a first bending by forming a metal plate into a bottomed cylindrical shape by pressing and forming a circular hole in the bottom of the processed product processed into the bottomed cylindrical shape. A step of forming a piece, a step of thinning a region corresponding to the inner peripheral surface on the opening side of a processed product processed into a bottomed cylindrical shape before the drawing, and a processing processed into a bottomed cylindrical shape A step of bending the thin-walled portion of the product radially outward and a step of forming a second bent piece by bending the thin-walled portion bent radially outward inward, The second bent piece is formed in an oblique posture so as to enter the inner side of the outer ring.
[0008]
Roller bearing obtained by the production method of the roller bearing according to the present invention, the second bending piece from being formed in the inclined posture so as to go enters the inside of the outer ring, the outer ring when the bending piece is subjected to external force It becomes difficult for the malfunction of deform | transforming so that it may fall further inside. Further, the roller is displaced in the axial direction even when the interference to the second bending piece, the end face is radially intermediate portion of the convex curved surface obtained by the above warp step on the inner surface of the bent piece of the roller Therefore, edge contact as in the conventional example does not occur.
[0009]
The convex curved surface includes a surface that is parallel to the roller end surface so as to come into contact with the end surface of the roller.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
1 to 3 show an embodiment of the present invention. In this embodiment, a shell needle roller bearing is taken as an example of the roller bearing. The needle roller bearing 3 in the illustrated example includes a shell-shaped outer ring 4 and a plurality of needle rollers 5, and is a full roller type.
[0011]
The shell-shaped outer ring 4 has a shape in which bent pieces 4b and 4c are provided on both axial sides of the cylindrical portion 4a. The shell-shaped outer ring 4 is manufactured by bending a single metal plate (such as a thin steel plate) by pressing.
[0012]
Both ends of the needle roller 5 have a shape substantially parallel to a surface orthogonal to the rotation axis, and the corners of the outer peripheral surface and the end surface are rounded and chamfered. The end faces of the needle rollers 5 are substantially parallel, but may have a slightly wavy shape. The needle roller 5 is restricted in its axial displacement by the two bent pieces 4 b and 4 c of the outer ring 4. A predetermined gap is provided between the end face of the needle roller 5 and the two bent pieces 4b and 4c.
[0013]
By the way, in the shell-shaped outer ring 4, the first bent piece 4b is set to be slightly thicker than the cylindrical portion 4a, but the second bent piece 4c and the cylindrical portion 4a are closer to the second bent piece 4c. This area is set to be thinner than the thickness of the raceway surface area of the cylindrical portion 4a. The reason why the second bent piece 4c is thus thin is that the second bent piece 4c is bent after the outer ring 4 is drawn into a bottomed cylindrical shape by pressing, This is to facilitate the subsequent bending work.
[0014]
In this embodiment, the first bent piece 4b is bent at an angle of approximately 90 degrees with respect to the cylindrical portion 4a as in the general case, but the bent shape of the second bent piece 4c is devised. is doing.
[0015]
That is, the second bent piece 4c is inclined so as to enter the inner side of the outer ring 4 from the surface X along the radial direction at the end of the cylindrical part 4a of the outer ring 4.
[0016]
The bending angle θ1 of the second bending piece 4c with respect to the cylindrical portion 4a can be set to be more than 90 degrees and less than 120 degrees, preferably 100 degrees. In other words, the angle θ2 sandwiched between the surface X along the radial direction and the center line Y of the second bent piece 4c is 0 to 30 degrees, but this angle θ2 can be preferably set to 10 degrees or less.
[0017]
The inner side surface of the second bent piece 4c is a convex curved surface 4d that is slightly curved.
[0018]
Next, an example of the manufacturing procedure of the shell-shaped outer ring 4 will be described.
[0019]
First, a single metal plate is drawn into a bottomed cylindrical shape by press working, and a circular hole is formed in the bottom of the processed product processed into the bottomed cylindrical shape. Thereby, the 1st bending piece 4b is obtained. In the stage before the drawing, the region corresponding to the inner peripheral surface on the opening side of the processed product processed into a bottomed cylindrical shape is thinned. This thinning can be performed by crushing in advance by pressing or by cutting. Thereafter, the second bent piece 4c is obtained by bending the thin portion of the processed product processed into a bottomed cylindrical shape inward in the radial direction.
[0020]
In this embodiment, in the process of performing the drawing, as shown in FIG. 3 (a), the thin portion 41 of the processed product processed into a bottomed cylindrical shape is warped in the radially outward direction in advance. As shown in FIG. 3 (b), by using two molds 15A and 15B to cut and remove the distal end side of the thin portion 41, in the distal end region on the inner peripheral surface of the thin portion 41, The convex curved surface 4d can be secured. If the thin portion 41 of the processed product thus obtained is bent as described above, the second bent piece 4c shown in FIG. 1 can be obtained.
[0021]
In the embodiment described above, the second bent piece 4c is inclined so as to enter the inner side of the outer ring 4, so that when the second bent piece 4c receives an external force, the second bent piece 4c further falls into the inner side of the outer ring 4. The product reliability can be improved, for example, the problem of deformation is less likely to occur.
[0022]
And since the convex curved surface 4d is provided in the inner surface of the 2nd bending piece 4c of the outer ring | wheel 4, as shown in FIG. 2, the needle roller 5 is displaced to an axial direction, and it becomes the 2nd bending piece 4c. When interfering with each other, the end surface of the needle roller 5 comes into contact with the middle portion in the radial direction of the convex curved surface 4d provided on the inner surface of the second bent piece 4c, as in the conventional example. Edge contact will not occur. Thereby, in the needle roller bearing 3 of this embodiment, like the conventional example, it is possible to reliably avoid the problem that the oil film is cut at the end face of the needle roller 5 and seizure occurs. As a result, the needle roller This can contribute to stabilization of the rolling characteristics of the needle roller bearing 3, such as being able to stabilize the rotational tone of No. 5.
[0023]
Even if the second bent piece 4c is deformed inward in the axial direction by receiving an external force, the intermediate portion in the radial direction of the convex curved surface 4d provided on the inner side surface of the second bent piece 4c is a needle. Since it contacts with the end surface of the shape roller 5, it can prevent that edge contact like the conventional example occurs.
[0024]
In addition, this invention is not limited only to embodiment mentioned above, Various application and deformation | transformation can be considered.
[0025]
(1) Although the shell-shaped needle roller bearing 3 has been described as an example in the above embodiment, a roller bearing can be used.
[0026]
(2) The shell-type needle roller bearing 3 shown in the above embodiment includes a cage ring 6 as shown in FIGS. 4 to 6. In this case, the inner diameter dimension of the first and second bent pieces 4b, 4c of the shell-shaped outer ring 4 is larger than the diameter (PCD) of the circle connecting the centers of the needle rollers 5. The inner peripheral surfaces of the first and second bent pieces 4b and 4c are in consideration of interference with the cage ring 6, and the diameter (PCD) of the circle connecting the centers of the needle rollers 5 or the cage. It is set substantially parallel to the outer peripheral surface of the ring 6. Further, as shown in FIG. 5, the outer diameter of the cage ring 6 is set smaller than the diameter (PCD) of the circle connecting the centers of the needle rollers 5, and the circumferential width W of the pocket 6a is set to be a needle. By setting the diameter smaller than the diameter R of the tapered roller 5, the needle roller 5 is prevented from coming out from the pocket 6a of the cage ring 6 toward the inner diameter side.
[0027]
As a result, when the cage ring 6 is displaced in the radial direction, the outer peripheral surface of the cage ring 6 comes into contact with the first and second bent pieces 4b and 4c and is guided. As a result, when the cage ring 6 interferes with the first and second bent pieces 4b and 4c, the cage ring 6 comes into contact with the surface without hitting the edge, so that the rotational tone of the cage ring 6 is adversely affected. It is not necessary to give.
[0028]
Incidentally, the cage ring 6 may be manufactured by injection molding a synthetic resin. Examples of the synthetic resin include synthetic resins having high strength and high heat resistance, such as PES (polyethersulfone), PPS (polyphenylene sulfide), PEEK (polyetheretherketone), nylon 46, nylon 66, and the like. it can. In this case, it can be manufactured easily and at a lower cost than the case of manufacturing by press working. In addition, when the cage ring 6 is made of a synthetic resin, when the cage ring 6 is in sliding contact with the bent pieces 4b and 4c of the outer ring 4, no sliding contact between the metals occurs. This is advantageous in that it is less likely to be damaged.
[0029]
【The invention's effect】
In the roller bearing obtained by the method for manufacturing a roller bearing according to the present invention , the second bent piece provided on one side of the outer ring in the axial direction is inclined so as to enter the inner side of the outer ring. Product reliability can be improved, for example, when it is subjected to an external force, it is less likely to be deformed so as to further fall into the inner side of the outer ring.
[0030]
Moreover, to contact when the rollers interferes against bending piece of said inclined posture, the end face is radially intermediate portion of the convexly curved surface is provided by a process warping the inner surface of the bent piece of the roller Therefore, it is not necessary to cause edge contact as in the conventional example. Therefore, it is possible to contribute to stabilization of the rolling characteristics of the roller bearing, such as stabilization of the rotation condition of the roller.
[0031]
Even if the bent piece in the oblique posture is deformed inward in the axial direction by receiving an external force, the radially intermediate portion of the convex curved surface provided on the inner side surface of the bent piece Since contact is made with the end face, it is possible to prevent edge contact as in the conventional example.
[Brief description of the drawings]
1 is a sectional view showing an upper half of a shell-shaped needle roller bearing according to an embodiment of the present invention. FIG. 2 is an enlarged view showing a state where the needle roller of FIG. 1 interferes with a second bent piece. FIG. 3 is a diagram showing a manufacturing procedure of the shell-shaped outer ring of FIG. 1. FIG. 4 is a shell-shaped needle roller bearing according to another embodiment of the present invention, corresponding to FIG. Fig. 6 is a cross-sectional view taken along the line (5)-(5) of Fig. 4. Fig. 6 is an enlarged view showing a state where the needle roller of Fig. 4 interferes with the second bent piece. Sectional view showing upper half of needle roller bearing [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 Shaft body 3 Needle roller bearing 4 Shell-shaped outer ring 5 Needle roller 6 Cage ring 4b First bent piece of outer ring 4c Second bent piece 4d of outer ring Convex curved surface of second bent piece

Claims (1)

Forming a first bent piece by drawing a metal plate into a bottomed cylindrical shape by pressing, and opening a circular hole in the bottom of the processed product processed into the bottomed cylindrical shape;
Thinning a region corresponding to the inner peripheral surface on the opening side of the processed product processed into a bottomed cylindrical shape in the stage before the drawing, and
Warping the thin-walled portion of the processed product processed into a bottomed cylindrical shape radially outward;
Forming a second bent piece by bending the thin-walled portion bent outward in the radial direction inward in the radial direction,
The method of manufacturing a roller bearing, wherein the second bent piece is formed in an oblique posture so as to enter the inner side of the outer ring.

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