JP2007276101A - Method of manufacturing annular forged part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an annular forged part, which manufactures at low costs an annular part formed with a bottom part having thickness smaller than thickness of the peripheral wall part thereof. <P>SOLUTION: A prepared annular raw material is forged to obtain an intermediate part 4 having an annular intermediate bottom part 42, a first intermediate peripheral wall part 43A formed on one surface side of the intermediate bottom part 42 and a second intermediate peripheral wall part 43B formed on the other surface side of the intermediate bottom part 42. The intermediate bottom part 42 of the intermediate part 4 is divided into two along the bottom surface thereof to obtain a pair of annular forged parts. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an annular forged component in which the thickness of the bottom portion is smaller than the thickness of the peripheral wall portion.

  For example, in an automobile transmission, annular parts (10A and 10B) as shown in FIGS. 9 and 10 are used as parts for holding a bearing and a one-way clutch. The annular component (10A / 10B) includes an annular bottom (12A / 12B) having a circular through hole (11A / 11B) in the center, and a cylindrical peripheral wall formed on one side of the bottom ( 13A and 13B), and the thickness of the bottom portion (T1A and T1B) is smaller than the thickness of the peripheral wall portion (T2A and T2B). As shown in FIG. 10, the bearing B or the like is held between the outer surface of the thick peripheral wall portion 13B of one annular component 10B and the inner surface of the thick peripheral wall portion 13A of the other annular component 10A.

Conventionally, as a method of manufacturing an annular component having a bottom thickness smaller than that of the peripheral wall portion, a method of forming a peripheral wall portion by drawing a steel plate and then thinning the bottom portion by cutting is generally used. is there. This is because in order to forge-mold a thin bottom directly by pressing, an extremely large forming load is required, and a large press device must be used. However, the manufacturing method by this cutting process has a large cutting allowance at the bottom, which has a drawback of increasing the manufacturing cost. In addition, the following patent document 1 describes a method for manufacturing a plate-shaped cold forged product having a recess in the center.
WO01 / 026840

  The present invention has been made in view of the above-described drawbacks in the conventional method for manufacturing an annular part, and it is possible to manufacture an annular part with a bottom thickness smaller than that of a peripheral wall portion at low cost. It is a technical problem to provide a method for manufacturing a ring-forged part that can be produced.

The present invention is a method for producing an annular forged part having an annular bottom portion and a peripheral wall portion formed on one surface side of the bottom portion, and the thickness of the bottom portion is smaller than the thickness of the peripheral wall portion,
A step of preparing an annular material;
Forging the annular material, an annular intermediate bottom, a first intermediate peripheral wall formed on one side of the intermediate bottom, and a second intermediate peripheral wall formed on the other side of the intermediate bottom A forging step to obtain an intermediate part having
Separating the intermediate bottom part of the intermediate part along the intermediate bottom part to obtain a pair of the annular forged parts.

  Further, the present invention is characterized in that the thickness of the intermediate bottom portion of the intermediate part is larger than the thickness of the first intermediate peripheral wall portion or the second intermediate peripheral wall portion.

  Moreover, this invention performs the cutting process which cuts the said intermediate | middle part obtained by the said forge process, It is characterized by performing the said separation process after that.

In the present invention, the cutting step comprises
A first holding step of holding the first intermediate peripheral wall portion of the intermediate part by a first chuck;
A first cutting step of cutting the second intermediate peripheral wall portion and / or the intermediate bottom portion of the intermediate part held by the first chuck;
A second holding step for releasing the holding of the first intermediate peripheral wall by the first chuck after holding the second intermediate peripheral wall of the intermediate part subjected to the first cutting step by a second chuck;
A second cutting step of cutting the first intermediate peripheral wall portion and / or the intermediate bottom portion of the intermediate part held by the second chuck;
It is characterized by including.

  Further, the present invention is characterized in that, in the separation step, the first intermediate peripheral wall portion of the intermediate part is held by the first chuck, and the second intermediate peripheral wall portion of the intermediate part is held by the second chuck. To do.

  According to the method for producing an annular forged part according to the present invention, an intermediate part having an intermediate bottom part, a first intermediate peripheral wall part, and a second intermediate peripheral wall part is formed by a forging process, and then the intermediate bottom part is formed into the bottom part by a separation process. Since a pair of annular forged parts can be manufactured by dividing into two, the thickness of the intermediate bottom part of the intermediate part can be set larger than the sum of the thicknesses of the bottom parts of the respective annular forged parts. it can. Therefore, compared with the case where each annular forged part is directly forged, the intermediate part can be forged with a remarkably small molding load, and the annular forged part can be manufactured at low cost. If the thickness of the intermediate bottom part of the intermediate part is set larger than the thicknesses of the first intermediate peripheral wall part and the second intermediate peripheral wall part, the intermediate part can be forged with a smaller forming load.

  Further, if the first intermediate peripheral wall portion or the second intermediate peripheral wall portion protruding from the intermediate bottom portion of the intermediate component is held by the first chuck or the second chuck, the intermediate component can be fixed easily and reliably. Therefore, the work efficiency of the cutting process and the separation process can be improved, and an annular forged part can be manufactured at a lower cost.

  Hereinafter, the manufacturing method of the annular forged part of the present embodiment will be described in the order of steps with reference to FIGS.

  First, as a preparation step, an annular material 3 shown in FIG. 1C is prepared. The annular material 3 has a predetermined thickness and is formed in an annular shape with a circular through hole 31 formed in the center. In the present embodiment, as shown in FIG. 1A, a round bar steel material is cut into a predetermined length to obtain a cylindrical material 1, and then the material 1 is cooled as shown in FIG. The disk-shaped material 2 is obtained by upsetting by intermediate forging, and the annular material 3 is obtained by punching the center of the material 2 into a circular shape.

  Next, as shown in FIG.1 (d), the intermediate component 4 is obtained by performing the forge process which cold-forms with respect to the cyclic | annular raw material 3. FIG. The intermediate part 4 includes an annular intermediate bottom portion 42, a first intermediate peripheral wall portion 43A formed on the outer peripheral edge of one surface side (lower surface side) of the intermediate bottom portion 42, and the other surface side (upper surface side) of the intermediate bottom portion 42. ) And a second intermediate peripheral wall portion 43B formed on the inner peripheral edge. The thickness S4 of the intermediate bottom portion 42 is formed larger than the thickness S5A of the first intermediate peripheral wall portion 43A and the thickness S5B of the second intermediate peripheral wall portion 43B.

  Further, in the present embodiment, an annular inward flange portion 44 is formed on the inner peripheral edge of one surface side (lower surface side) of the intermediate bottom portion 42 by this forging step, and a circular shape is formed on the inner peripheral edge of the inward flange portion 44. A shaped through hole 41 is formed. Although the thickness of the inward flange portion 44 is smaller than the thickness S5A of the first intermediate peripheral wall portion 43A, no wall portion exists on the inner peripheral edge of the inward flange portion 44. Therefore, the inward flange portion 44 can be molded without applying a large molding load.

  Further, by this forging process, an annular outward flange portion 45 is formed on the outer peripheral edge of the other surface side (upper surface side) of the intermediate bottom portion 42, and a cylindrical mounting wall portion is formed on the outer peripheral edge of the outward flange portion 45. 46 is molded. The thickness of the outward flange portion 45 is formed smaller than the thickness S5B of the second intermediate peripheral wall portion 43B, and the mounting wall portion 46 is formed on the outer peripheral edge of the outward flange portion 45. The thickness S6 of the mounting wall portion 46 is substantially the same as the thickness of the outward flange portion 45. Therefore, the outward flange portion 45 and the mounting wall portion 46 can be molded without applying such a large molding load.

  Next, as shown in FIGS. 2 and 3, a cutting process for cutting the intermediate part 4 is performed. In the present embodiment, the following steps are sequentially performed as the cutting process. First, as shown in FIG. 2, a first holding step is performed in which the first intermediate peripheral wall 43A of the intermediate part 4 is held by a known first chuck C1, and then the intermediate part 4 held by the first chuck C1 is performed. A first cutting step of cutting the second intermediate peripheral wall 43B and the like with a cutting tool B1 such as a cutting tool is performed (see FIG. 2). Then, the second intermediate peripheral wall 43B is sandwiched and held by the known second chuck C2 while the first intermediate peripheral wall 43A is held by the first chuck C1, and then the second chuck is released from being held by the first chuck C1. A holding step is performed, and then a second cutting step is performed in which the first intermediate peripheral wall portion 43A and the like of the intermediate part 4 held by the second chuck C2 is cut by a cutting tool B2 such as a cutting tool (see FIG. 3).

  In the present embodiment, in the first cutting step, while appropriately changing the cutting tool B1, the second intermediate peripheral wall portion 43B of the intermediate part 4, the other surface side of the intermediate bottom portion 42, the other surface side of the inward flange portion 44, Each of the other surface side of the outward flange portion 45 and the mounting wall portion 46 is subjected to finish cutting. Then, a plurality of fastening holes 47 are formed in the inward flange portion 44 so as to surround the through hole 41. Further, in the second cutting step, while appropriately changing the cutting tool B2, for the first intermediate peripheral wall portion 43A of the intermediate part 4, the one surface side of the intermediate bottom portion 42, and the one surface side of the inward flange portion 44, respectively, Apply finish cutting.

  In the present embodiment, as shown in FIG. 2, in the first holding step, the intermediate component 4 is held by the first chuck C1 with the outer surface of the first intermediate peripheral wall portion 43A being sandwiched therebetween. The inner surface of the peripheral wall portion 43A may be supported and held by another chuck. In the second holding step shown in FIG. 3, instead of holding the outer surface of the second intermediate peripheral wall 43B with the second chuck C2, the inner surface of the first intermediate peripheral wall 43A is supported and held by another chuck. In addition, the outer surface or the inner surface of the mounting wall portion 46 may be supported and held.

  Next, as shown in FIGS. 4 and 5, a separation step is performed in which the intermediate bottom portion 42 of the intermediate part 4 subjected to the cutting step is divided into two along the intermediate bottom portion 42. In the present embodiment, as shown in FIG. 4, the first chuck C1 holds the first intermediate peripheral wall portion 43A of the intermediate part 4, and the second chuck C2 holds the second intermediate peripheral wall portion 43B. By cutting the center of the outer peripheral surface of the intermediate bottom portion 42 with a cutting tool B3 such as a cutting tool while rotating the intermediate component 4, the intermediate bottom portion 42 is cut in parallel to the bottom surface (one surface and the other surface) of the intermediate bottom portion 42. To do. A one-dot chain line indicated by reference numeral A1 in FIG. 4 indicates a cutting allowance by the cutting tool B3.

  By this separation step, a pair of annular forged parts 5A and 5B are obtained from one intermediate part 4 as shown in FIG. In the present embodiment, after the separation step, the forged part 5A is held by the first chuck C1 while finishing the cutting surface 50A during the separation step, and the annular forged part 5B is processed by the second chuck C2. The cut surface 50B at the time of the separation process is finished and cut while holding, but it is not always necessary to finish each cut surface.

  As shown in FIG. 6, the pair of annular forged parts 5A and 5B obtained in this way are formed on annular bottom portions 52A and 52B having circular through holes 51A and 51B in the center, and on one surface side of these bottom portions. The cylindrical peripheral wall portions 53A and 53B are formed, and the thicknesses T5A and T5B of the bottom portions 52A and 52B are formed smaller than the thicknesses T6A and T6B of the peripheral wall portions. In the annular forged component 5A, a peripheral wall portion 53A is formed on the outer peripheral edge of the bottom portion 52A, and a plurality of fastening holes 54A are formed in the bottom portion 52A. Further, the annular forged component 5B has a peripheral wall 53B formed on the inner periphery of the bottom 52B, and a cylindrical mounting wall 54B having a thickness T7 substantially the same as the thickness T5B of the bottom 52B on the outer periphery of the bottom 52B. It has.

  Thus, in the manufacturing method of the annular forged part of the present embodiment, first, the intermediate part 4 having the intermediate bottom part 42 is formed by the forging process, and then the intermediate bottom part 42 is moved along the bottom face by the separation process. By bisecting, a pair of annular forged parts 5A and 5B is manufactured. Therefore, the thickness S4 of the intermediate bottom part 42 of the intermediate part 4 to be forged is set to be larger than the sum of the thickness T5A of the bottom part 52A of the annular forged part 5A and the thickness T5B of the bottom part 52B of the annular forged part 5B. it can. Therefore, the intermediate part 4 can be forged with a remarkably small molding load, compared with the case where individual annular forged parts are directly forged, and the annular forged parts 5A and 5B can be manufactured at low cost.

  In the present embodiment, the thickness S4 of the intermediate bottom portion 42 of the intermediate component 4 is set larger than the thickness S5A of the first intermediate peripheral wall portion 43A and the thickness S5B of the second intermediate peripheral wall portion 43B. Therefore, the intermediate part 4 can be forged with a smaller molding load, and the annular forged parts 5A and 5B can be manufactured at a lower cost.

  Further, since the thickness S4 of the intermediate bottom portion 42 of the intermediate part 4 can be set larger than the thicknesses T5A and T5B of the bottom parts of the annular forged parts 5A and 5B, the intermediate part 4 is subjected to heat treatment such as surface hardening. By doing so, it is possible to reduce the heat treatment distortion as compared with the case where the individual annular forged parts 5A and 5B are heat-treated, and the yield of the annular forged parts can be improved.

  Furthermore, in the present embodiment, the first intermediate circumferential wall 43A or the second intermediate circumferential wall 43B protruding from the intermediate bottom 42 of the intermediate component 4 is held by the first chuck C1 or the second chuck C2 to thereby obtain the intermediate component. 4 can be fixed easily and reliably. Therefore, the working efficiency of the cutting process and the separation process for the intermediate part 4 can be greatly improved, and the manufacturing cost of the annular forged part can also be reduced.

  As mentioned above, although the manufacturing method of the annular forged part of this embodiment was demonstrated, this invention can be implemented also with another form.

  For example, in the above embodiment, a pair of annular forged parts 5A and 5B having different shapes are manufactured from the intermediate part 4 having the first intermediate peripheral wall part 43A and the second intermediate peripheral wall part 43B. The present invention is by no means limited to this, and a pair of annular forged parts 8 and 8 having the same shape may be manufactured from the intermediate part 7 as shown in FIG.

  That is, first, as shown in FIG. 7A, an annular material 6 having a circular through hole 61 at the center is prepared, and then a forging process is performed on the annular material 6 in a cold manner. Thus, the intermediate part 7 is forged. As shown in FIG. 7B, the intermediate part 7 includes an annular intermediate bottom portion 72, a first intermediate peripheral wall portion 73 </ b> A formed on the outer peripheral edge on one surface side of the intermediate bottom portion 72, and the intermediate bottom portion 72. The first intermediate peripheral wall portion 73A and the second intermediate peripheral wall portion 73B are formed in the same shape. The thickness S7 of the intermediate bottom portion 72 is formed larger than the thickness S8 of the first intermediate peripheral wall portion 73A and the second intermediate peripheral wall portion 73B. If the intermediate bottom portion 72 of the intermediate part 7 is divided in the middle along the bottom surface, a pair of annular forged parts 8 and 8 having the same shape can be manufactured as shown in FIG. An alternate long and short dash line indicated by a symbol A2 in the drawing indicates a cutting allowance of the intermediate part 7. Each annular forged component 8 has an annular bottom 82 having a circular through hole 81 formed in the center, and a cylindrical peripheral wall 83 formed on one surface side of the bottom 82, and has a thickness T8 of the bottom 82. However, it is formed smaller than the thickness T9 of the peripheral wall 83.

  Moreover, in the said embodiment, a round bar steel material is cut | disconnected to predetermined length, the column-shaped raw material 1 is obtained, then this raw material 1 is upset by cold forging, and the disk-shaped raw material 2 is obtained, And although the cyclic | annular raw material 3 is obtained by carrying out the punching process of the center of this raw material 2 circularly, this invention is not limited to this naturally, For example, it shows to Fig.8 (a), (b) As described above, the annular material 9 may be obtained by cutting the round pipe member 90 having a predetermined dimension into a predetermined length. The round pipe material 90 may be a hot-rolled pipe material as it is, or a hot-rolled pipe material that has been cold drawn and then subjected to a heat treatment such as an annealing treatment. May be. Also, as shown in FIGS. 10C and 10D, the intermediate material 40 is formed by forging the annular material 9, and then the intermediate material 40 is forged by performing the forging process on the intermediate material 40. 4 may be obtained. Of course, you may make it obtain the intermediate | middle part 7 shown in FIG.7 (b) by performing a forge process with respect to the cyclic | annular raw material obtained by round-cutting a round pipe material.

  Moreover, in the said embodiment, although the forging process is performed in cold, of course, this invention is not limited to this, You may perform a hot forging process and a warm forging process. Moreover, in the said embodiment, although the cutting process is performed as a isolation | separation process, you may perform isolation | separation by a parting process or a shearing process.

  In addition, the present invention can be implemented in a mode in which various improvements, corrections, and modifications are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. In addition, any invention-specific matters may be replaced with other technologies within a range where the same action or effect occurs, and the integrally-configured invention-specific matters are constituted by a plurality of members. Or may be implemented in a form in which the invention-specific matters configured from a plurality of members are integrally configured.

It is a cross-sectional view explaining the preparation process and forging process of the manufacturing method of the annular forged component of this embodiment. It is a cross-sectional view explaining the cutting process of the manufacturing method. It is a cross-sectional view explaining the cutting process of the manufacturing method. It is a cross-sectional view explaining the isolation | separation process of the manufacturing method. It is a cross-sectional view explaining the isolation | separation process of the manufacturing method. It is a cross-sectional view of the annular forged part obtained by the manufacturing method. It is a cross-sectional view explaining the outline of the process of the other modified example of the manufacturing method of the annular forged part which concerns on this invention. It is a cross-sectional view explaining the outline of the process of the further another modification of the manufacturing method of the annular forged part which concerns on this invention. It is a cross-sectional view of a conventional annular part. It is a cross-sectional view which shows the usage example of the conventional annular component.

Explanation of symbols

3, 6, 9; annular material 4, 7; intermediate parts 42, 72; intermediate bottom portions S4, S7; thickness 43A, 73A (intermediate bottom portion); first intermediate peripheral wall portions S5A, S8; (first intermediate peripheral wall portion) ) Thickness 43B, 73B; second intermediate peripheral wall S5B, S8; thickness 5A, 5B, 8 (second intermediate peripheral wall); annular forged parts 52A, 52B, 82; bottom T5A, T5B, T8; Thickness 53A, 53B, 83; Peripheral wall portions T6A, T6B, T9; Thickness C1 (peripheral wall portion) First chuck C2 Second chuck

Claims (5)

A method for producing an annular forged part having an annular bottom and a peripheral wall formed on one side of the bottom, wherein the thickness of the bottom is smaller than the thickness of the peripheral wall,
A step of preparing an annular material;
Forging the annular material, an annular intermediate bottom, a first intermediate peripheral wall formed on one side of the intermediate bottom, and a second intermediate peripheral wall formed on the other side of the intermediate bottom A forging step to obtain an intermediate part having
Separating the intermediate bottom of the intermediate part along the intermediate bottom to obtain a pair of annular forged parts;
A method for producing an annular forged part, comprising:   The method of manufacturing an annular forged part according to claim 1, wherein the thickness of the intermediate bottom part of the intermediate part is larger than the thickness of the first intermediate peripheral wall part or the second intermediate peripheral wall part.   The method for producing an annular forged part according to claim 1 or 2, wherein a cutting process for cutting the intermediate part obtained by the forging process is performed, and then the separation process is performed. The cutting step is
A first holding step of holding the first intermediate peripheral wall portion of the intermediate part by a first chuck;
A first cutting step of cutting the second intermediate peripheral wall portion and / or the intermediate bottom portion of the intermediate part held by the first chuck;
A second holding step for releasing the holding of the first intermediate peripheral wall by the first chuck after holding the second intermediate peripheral wall of the intermediate part subjected to the first cutting step by a second chuck;
A second cutting step of cutting the first intermediate peripheral wall portion and / or the intermediate bottom portion of the intermediate part held by the second chuck;
The method for producing an annular forged part according to claim 3, comprising: The said separation process WHEREIN: The 1st intermediate | middle peripheral wall part of the said intermediate component is hold | maintained by the said 1st chuck | zipper, and the 2nd intermediate | middle peripheral wall part of this intermediate | middle part is hold | maintained by the said 2nd chuck | zipper, Manufacturing method of annular forged parts.

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