JP5012038B2 - Metal ring manufacturing method - Google Patents

Description

  The present invention relates to an improvement in a method for manufacturing a metal short cylindrical seal ring incorporated in a shell type needle bearing for the purpose of, for example, reducing the flow rate of lubricating oil passing through the shell type needle bearing.

For example, a shell-type needle bearing 1 as shown in FIG. 8A is incorporated in a rotation support portion to which a large radial load is applied, such as an automatic transmission for an automobile. This shell type needle bearing 1 is formed by holding a plurality of needles 3 on the inner diameter side of a flanged outer ring 2 called a shell. In a state where such a shell type needle bearing 1 is incorporated in the rotation support portion, lubricating oil is circulated in the axial direction to lubricate the shell type needle bearing 1 and the movable portion further downstream. The shell type needle bearing 1 shown in FIG. 8A has a low resistance to the flow of the lubricating oil. For this reason, the amount of lubricating oil supplied to each part may become inappropriate if it is left as it is. Therefore, in such a case, as shown in FIG. 8B, a shell type needle bearing 1a in which the seal ring 4 is incorporated together with each needle 3 on the inner diameter side of the flanged outer ring 2 is used. The seal ring 4 becomes a resistance against the flow of the lubricating oil passing through the inner diameter side of the flanged outer ring 2 and makes the amount of the lubricating oil supplied to the respective parts appropriate.

  For example, the seal ring 4 incorporated in a shell-type needle bearing that constitutes a rotation support portion of an automobile transmission has a thin wall thickness (cross-sectional height) of about 1.0 to 2.5 mm, for example, in the radial direction. . Further, the inner and outer diameters are related to the outer diameter of the rotary shaft arranged on the inner diameter side of the seal ring 4 or the inner diameter of the brazed outer ring 2 arranged on the outer diameter side according to the degree to which the flow rate of the lubricating oil should be reduced. Regulate with. Furthermore, the axial dimension of the seal ring 4 is also regulated according to the degree to which the flow rate of the lubricating oil should be reduced and the difference between the axial dimension of the brazed outer ring 2 and the axial dimension of each needle 3. . Therefore, in order to squeeze the lubricating oil as desired and allow the shell-type needle bearing 1a to function normally, it is necessary to ensure the accuracy of the dimensions (inner / outer diameter and axial length) of the seal ring 4. .

  For this reason, in the past, the seal ring 4 was made by cutting such as turning, but it was inevitable that the cost would increase. On the other hand, Patent Documents 1 and 2 describe a method of making a short cylindrical metal part by plastic working. However, the manufacturing methods described in these Patent Documents 1 and 2 are not intended to produce a high-precision thin ring like the seal ring 4. Therefore, depending on the manufacturing method described in Patent Documents 1 and 2, a high-accuracy thin-walled ring, such as the above-described seal ring 4, that is thin and needs to sufficiently secure the accuracy of the inner and outer diameters and the cross-sectional shape. It is difficult to build.

Japanese Patent Laid-Open No. 10-146642 JP 2000-94080 A

  In view of the circumstances as described above, the present invention is a high-accuracy thin-walled ring that is thin and has sufficient inner and outer diameter dimensions and cross-sectional accuracy, such as a seal ring incorporated in a shell-type needle bearing. Is invented to realize a manufacturing method that can be manufactured at low cost.

The manufacturing method of the metal ring of the present invention includes the following first to fourth steps.
“First step”: A ring-shaped first intermediate material is formed by punching a metal plate.
“Second step”: By applying a burring process that bends the portion of the first intermediate material closer to the inner diameter at right angles to the axial direction, the cylindrical portion and the outward fold that is bent radially outward from one axial end portion of the cylindrical portion A second intermediate material having an L-shaped cross section and having an annular shape as a whole is provided.
“Third step”: The outwardly-extending flange portion of the second intermediate material is removed to obtain a cylindrical third intermediate material. “Fourth step”: The inner and outer diameters and the cross-sectional shape of the third intermediate material are adjusted by cold rolling to obtain a metal ring having the required shape accuracy and dimensional accuracy. The shape accuracy includes not only the accuracy related to the cross-sectional shape but also the accuracy related to the entire shape such as roundness.

When the manufacturing method of the metal ring of the present invention as described above is carried out, specifically, as described in claim 2, the third intermediate material is made of an annular die in the fourth step. Hold on the inner surface. In this state, the inner peripheral surface of the third intermediate material is pressed against the inner peripheral surface of the die by the roller.
In carrying out the invention described in claim 2, preferably, as described in claim 3, the third step has an outer diameter that matches the outer diameter of the metal ring after completion. Forming a third intermediate material; Thereafter, in the fourth step, the outer diameter of the third intermediate material is not changed, and the inner diameter and the shape of the inner peripheral surface are changed.
When the present invention is carried out, preferably, as described in claim 4, after the first step, before the fourth step, that is, between the first step and the second step, Between the second step and the third step or between the third step and the fourth step, an intermediate material (any one of the first to third intermediate materials) )) Is preformed. And the cross-sectional shape of at least one edge of the outer peripheral surface both ends edge of the said intermediate material is made into the convex circular arc shape of 1/4 arc shape, for example.

According to the metal ring manufacturing method of the present invention configured as described above, it is possible to manufacture a high-accuracy thin-walled ring that is thin and requires sufficient accuracy of inner and outer diameter dimensions and cross-sectional shapes at low cost. .
That is, in the case of the manufacturing method of the present invention, if the thickness of the metal plate as the raw material is selected according to the radial thickness of the metal ring to be manufactured, the thickness dimension is necessary even for a thin metal ring. In addition, it is possible to produce a high-accuracy thin ring with good shape accuracy while ensuring sufficient accuracy of the inner and outer diameters.
In particular, as shown in claims 2 and 3, if the third intermediate material is cold-rolled with the third intermediate material held on the inner peripheral surface of the die, excellent shape accuracy and dimensional accuracy are obtained. It is possible to efficiently make a metal ring having
Furthermore, as described in claim 4, if preforming is performed so that the cross-sectional shape of the outer peripheral surface edge of the intermediate material is a convex arc shape, a high-quality metal ring whose edge is not a sharp edge can be efficiently obtained. Can be made well.

[First example of embodiment]
1-4 show a first example of an embodiment of the present invention corresponding to claims 1 to 3. The material of the metal plate used in the practice of the present invention is not particularly limited as long as it is a plastically deformable material, but generally an iron-based alloy such as a mild steel plate such as a low carbon steel plate is used. However, a non-ferrous metal such as copper or a copper-based alloy, aluminum, or an aluminum-based alloy can be used as necessary.
In the metal ring manufacturing method of this example, first, a long metal plate drawn out from an uncoiler is punched into a circular shape by a press or the like, thereby forming a material 5 as shown in FIG. .
Next, as a first step, the center part of the material 5 is punched out by punching using a press or the like, so that the first intermediate material 6 having an annular shape as shown in the upper part of FIG. The disc-like scrap 7 shown in the lower part of FIG. 1B generated as a result of punching is discarded or used as a material for making a metal ring with a smaller diameter.

As a second step, the first intermediate material 6 is subjected to a burring process in which a portion near the inner diameter of the first intermediate material 6 is bent at right angles to the axial direction. In the burring process, as is widely known in the field of metal processing, the first intermediate material 6 is held in a state where the outer diameter portion of the first intermediate material 6 is clamped from both sides in the axial direction by a pair of holding dies. This is done by pushing a punch die into the inner diameter portion of the intermediate material 6. A cross section provided with a cylindrical portion 8 and an outward flange portion 9 bent radially outward from one axial end portion of the cylindrical portion 8 as shown in FIG. The second intermediate material 10 is L-shaped and annular in its entirety. According to the metal ring manufacturing method of the present invention, a high-precision thin ring is made from the cylindrical portion 8 of the second intermediate material 10. On the other hand, a portion of the outward flange portion 9 that is present radially outward from the outer peripheral surface of the cylindrical portion 8 is an annular scrap 11 {(D of FIG. ) Refer to the lower section} and discard.
In the subsequent third step, the second intermediate material 10 is punched by pressing or the like, and the outward flange 9 is removed to form a cylinder as shown in the upper part of FIG. The third intermediate material 12 is shaped like a sheet. The outer diameter of the third intermediate material 12 coincides with the outer diameter of the metal ring 13 to be manufactured.

  The third intermediate material 12 obtained in this way is subjected to cold rolling in the subsequent fourth step. Then, by the plastic working by the cold rolling process, the inner and outer diameters and the cross-sectional shape of the third intermediate material 12 are adjusted, and the metal having the required shape accuracy and dimensional accuracy as shown in FIG. The ring 13 is used. The cold rolling process for processing the third intermediate material 12 into the metal ring 13 will be described in detail with reference to FIGS.

  The third intermediate material 12 is fitted and supported by an annular die 14. The die 14 has both inner and outer peripheral surfaces that are concentric cylindrical surfaces, and a plurality of support rollers (not shown) in which each outer peripheral surface is in rolling contact with the outer peripheral surface of the die 14 (in the radial direction). It is supported only for rotation (with displacement prevented). The die 14 has an inner diameter that matches the outer diameter of the metal ring 13 (and the third intermediate material 12) to be manufactured. During the fourth step, the third intermediate material 12 is held on the inner peripheral surface of the die 14. In this state, the third intermediate material 12 is pressed in the direction of the arrow in FIG. 2 toward the inner peripheral surface of the die 14 by the pressing roller 15 which is a roller described in the claims.

  On the outer peripheral surface of the intermediate portion of the pressing roller 15, a concave groove 16 is formed over the entire periphery in a portion aligned with the third intermediate material 12. The cross-sectional shape of the concave groove 16 is rectangular, and the width dimension in the axial direction matches the width dimension of the metal ring 13 to be formed. Further, the depth of the concave groove 16 in the radial direction of the pressing roller 15 is set to be equal to or less than the thickness dimension of the metal ring 13 to be manufactured. When the third intermediate material 12 is processed into the metal ring 13, the pressing roller 15 is pressed against the inner peripheral surface of the die 14 while rotating. A part of the third intermediate material 12 in the circumferential direction is strongly suppressed between the inner peripheral surface of the die 14 and the inner surface of the concave groove 16.

  As the pressing roller 15 is pressed, the die 14 supports the pressing force of the pressing roller 15 while rotating in the same direction as the rotation direction of the pressing roller 15. The third intermediate material 12 also rotates with the die 14. Accordingly, a portion of the third intermediate material 12 that is strongly restrained between the inner peripheral surface of the die 14 and the inner surface of the concave groove 16 continuously changes in the circumferential direction. As a result, the cross-sectional shape of the third intermediate material 12 changes as shown in FIGS. 4A to 4B over the entire circumference. That is, the third intermediate material 12 is plastically deformed so that the cross-sectional shape of the third intermediate material 12 matches the inner peripheral surface of the die 14 and the inner surface of the concave groove 16, thereby forming the metal ring 13. That is, at the time of the fourth step using the die 14 and the pressing roller 15, the outer diameter and the outer peripheral surface of the third intermediate material 12 are not changed, and the inner diameter and the inner peripheral shape are changed. Then, the metal ring 13 is processed.

  According to the manufacturing method of the metal ring of the present example configured as described above, the metal ring is a high-accuracy thin ring that is thin and needs to have sufficient inner and outer diameter dimensions and cross-sectional accuracy. The ring 13 can be manufactured at low cost. In other words, in the case of the manufacturing method of this example, if the thickness of the metal plate to be the material 5 is selected according to the radial thickness of the metal ring 13 to be manufactured, even the thin metal ring 13 has a thickness. While ensuring the necessary accuracy with respect to dimensions, in other words, it is possible to produce a high-accuracy thin ring with good accuracy in terms of shape accuracy while sufficiently ensuring the accuracy of the inner and outer diameters. In particular, since the cold rolling process for processing the third intermediate material 12 into the metal ring 13 is performed using the die 14 and the pressing roller 15 as described above, it has excellent shape accuracy and dimensional accuracy. The metal ring 13 can be made efficiently.

[Second Example of Embodiment]
FIGS. 5-7 has shown the 2nd example of embodiment of this invention corresponding to Claims 1-4. In the case of the above-mentioned first example, the four corners of the cross-sectional shape of the metal ring 13 to be obtained (both axial end edges of the inner and outer peripheral surfaces) were pointed (the radius of curvature of the cross-sectional shape of the part was extremely small). . On the other hand, in the case of this example, it is intended that the four corners of the cross-sectional shape be convex arc surfaces (form corner R). Regarding the corners R of the inner peripheral edge in the axial direction, even in the second example of the embodiment described above, if the corners R are provided at the bottom corners of the concave grooves 16 formed on the outer peripheral surface of the pressing roller 15 (bottom corners). (If the cross-sectional shape of the part is a concave arc surface), it can be formed. On the other hand, if the corners R at both ends in the axial direction of the outer peripheral surface are made only by the shape of the inner peripheral surface of the die, the completed metal ring cannot be taken out from the inner peripheral surface of the die.

  In view of such circumstances, the manufacturing method of the present example includes a metal ring 13a in which corners R are formed not only on both axial edges of the inner peripheral surface but also on both axial edges of the outer peripheral surface, from the die 14a. The idea is to realize a manufacturing method that can be taken out. 5A to 5C showing the manufacturing method of this example, (A) to (C) are the same as (A) to (C) of FIG. 1 showing the first example of the embodiment described above. FIG. 5E is the same as FIG. 1D except that a corner R portion 17 described below is formed in part. The feature of this example is that the preliminary processing step shown in FIG. 5D is provided and the shape of the inner peripheral surface of the die 14a used in the cold rolling process performed in (F) is devised. Therefore, overlapping illustrations and descriptions regarding the same parts as those of the first example of the above-described embodiment are omitted or simplified, and hereinafter, different parts from the first example will be mainly described.

  In the case of the metal ring manufacturing method of the present example, which is considered with the above-described intention, FIG. 6 shows one end edge of the outer peripheral surface of the third intermediate material 12a shown in the upper part of FIG. A corner R portion 17 as shown is formed. The step of forming the corner R portion 17 may be performed before the third intermediate material 12a is set on the inner peripheral surface of the die 14a shown in FIG. 7 (internally fitted into the annular die 14a). That is, the process may be performed between (B) and (C), between (C) and (E), and between (E) and (F) in FIG. In the case of this example, before the second intermediate material 10 shown in (C) is processed into the third intermediate material 12a shown in (E), the outer peripheral surface of the cylindrical portion 8 in FIG. A corner R portion 17 as shown in FIG. 6 is formed at the leading edge. The corner R portion 17 is formed in such a manner that the cylindrical portion 8 is externally fitted to the cylindrical core, and a concave arcuate surface-like pressure is applied to the distal end edge of the outer peripheral surface of the cylindrical portion 8. This is done by pressing an annular pressing die formed over the entire surface and plastically deforming the outer edge of the outer peripheral surface.

In preliminary processing steps performed in this manner, the formation of the corner R portion 17 on the outer circumferential surface leading edge of the upper Kien tubular portion 8, the pre-intermediate material 18 shown in (D) in FIG. 5, described above As in the case of the first example of the embodiment, punching by press working or the like is performed. And the outward eaves part 9 is removed and it is set as the cylindrical 3rd intermediate | middle raw material 12a as shown to the upper stage part of (E) of FIG. Of the both end edges in the axial direction of the inner and outer peripheral surfaces of the third intermediate material 12a, the corner R portion is provided at one axial end edge of the outer peripheral surface. In contrast, the other axial end edge of the outer peripheral surface and the both axial end edges of the inner peripheral surface remain pointed. Therefore, when adjusting the inner and outer diameters and the cross-sectional shape of the third intermediate material 12a in the fourth step shown in FIGS. 5E to 5F, the other axial end edge and the inner peripheral surface of the outer peripheral surface are arranged. Corner R portions are formed at both ends in the axial direction. And it is set as the said metal ring 13a which forms the corner | angular R part in all the four corner parts of cross-sectional shape, and has the required shape precision and dimensional accuracy.

  In order to obtain such a metal ring 13a, the inner peripheral surface of the annular die 14a used in the fourth step is composed of a large diameter portion 19 which is a concentric cylindrical surface and a small diameter as shown in FIG. A stepped cylindrical surface in which the portion 20 is continuous with the stepped portion 21 is used. Further, the stepped portion 21 is a concave arc surface whose cross-sectional shape is a quarter arc. Further, the bottom axial end corners of the concave groove 16a formed on the outer peripheral surface of the pressing roller 15a are also concave arc surfaces having a quarter arc shape in cross section. About the structure of the other part regarding a cold rolling processing apparatus, it is the same as that of the case of the 1st example of embodiment mentioned above.

  In the case of this example, the third intermediate material 12a is provided on the die 14a, and the stepped portion 21 that is the concave arc surface provided on the inner peripheral surface of the die 14a is provided on the outer peripheral surface of the third intermediate material 12a. The other end in the axial direction (pointed edge) is fitted in the opposite direction. Then, as in the case of the first example of the above-described embodiment, the third intermediate material 12a is pressed against the inner peripheral surface of the die 14a by the pressing roller 15a. As a result of this pressing, the cross-sectional shape of the third intermediate material 12a changes over the entire circumference as shown in FIGS. That is, the third intermediate material 12a is plastically deformed so that the cross-sectional shape of the third intermediate material 12a matches the inner peripheral surface of the die 14a and the inner surface of the concave groove 16a, thereby forming the metal ring 13a. At this time, the shape of the concave arc surface constituting the corners on both ends in the bottom axial direction of the concave groove 16a is at the both edges of the inner peripheral surface of the third intermediate material 12a, and the shape of the stepped portion 21 is the third intermediate material. Transferred to the other axial end edge of the outer peripheral surface of 12a. Since the corner R portion 17 is originally formed at one end edge in the axial direction of the outer peripheral surface of the third intermediate material 12a, both inner and outer peripheral surfaces of the metal ring 13a obtained as a result of the fourth step. Corner end R portions each having a quarter arc shape in cross section are formed at both end edges in the axial direction.

  According to the metal ring manufacturing method of the present example configured as described above, corner R portions each having a quarter arc shape in cross section are formed at both axial end edges of the inner and outer peripheral surfaces. A high-quality metal ring 13a can be efficiently manufactured by an industrial method. That is, if the corner R portions are simply formed at both end edges in the axial direction of both the inner and outer peripheral surfaces, the metal ring 13 made in the first example of the embodiment described above is subjected to machining such as turning and grinding. It can be made by applying. However, in the method of forming the corner R portion by such machining, the machining cost is increased, and the obtained metal ring, and thus various machines such as an automobile transmission incorporating this metal ring are incorporated. It is inevitable that the cost of the apparatus increases. On the other hand, according to the manufacturing method of this example, the manufacturing cost of the metal ring 13a can be kept low.

  The production method of the present invention is not limited to the seal ring incorporated in the shell-type needle bearing as described above, but can be used for producing a high-precision thin ring incorporated in various mechanical devices such as electrical equipment and precision machines.

Sectional drawing which shows the 1st example of embodiment of this invention in process order. The side view which shows the implementation condition of cold rolling process. FIG. 4 is a cross-sectional view taken along the line aa in FIG. 3. 3A is an enlarged view of a portion b in FIG. 3, showing a state before the start of the cold rolling process, and FIG. Sectional drawing which shows the 2nd example of embodiment of this invention in order of a process. The c section enlarged view of (D) of FIG. (A) is the same figure as FIG. 4 which shows the state before the start of cold rolling, and (B) shows the state after a process, respectively. The fragmentary sectional view which shows two examples of the structure of the shell type needle bearing known conventionally.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Shell type needle bearing 2 Outer ring | wheel with 3 ribs 3 Needle 4 Seal ring 5 Material 6 First intermediate material 7 Disc-shaped scrap 8 Cylindrical part 9 Outward flange part 10 Second intermediate material 11 Toroidal scrap 12, 12a Third intermediate Material 13, 13a Metal ring 14, 14a Die 15, 15a Pressure roller 16, 16a Groove 17 Corner R part 18 Preliminary intermediate material 19 Large diameter part 20 Small diameter part 21 Step part

Claims (4)

  A cylindrical part and a cylindrical part of the cylindrical part are formed by punching a metal plate and performing a burring process in which a portion near the inner diameter of the first intermediate material is bent at right angles to the axial direction. A second step with an L-shaped cross section and an overall annular intermediate material with an outward flange bent radially outward from one end in the axial direction, and removing the outward flange of this second intermediate material A third step of forming a cylindrical third intermediate material, and adjusting the inner and outer diameters and cross-sectional shape of the third intermediate material by cold rolling, and a metal ring having the required shape accuracy and dimensional accuracy A metal ring manufacturing method comprising a fourth step.   The third intermediate material is held on the inner peripheral surface of the annular die during the fourth step, and the inner peripheral surface of the third intermediate material is pressed against the inner peripheral surface of the die by a roller. The manufacturing method of metal rings described in 1.   In the third step, after forming the third intermediate material having an outer diameter that matches the outer diameter of the finished metal ring, in the fourth step, the outer diameter of the third intermediate material is not changed, and the inner diameter and The manufacturing method of the metal ring of Claim 2 which changes the shape of an internal peripheral surface.   After the first step and before the fourth step, preforming is performed in which the cross-sectional shape of at least one edge of the outer peripheral surface both ends of the intermediate material is a convex arc shape. The manufacturing method of metal rings described in any one of the above.

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