JP4530656B2 - Tooth profile forming part with flange and manufacturing method thereof - Google Patents

Description

  The present invention relates to a flanged tooth forming part suitable for use in a transmission for automobiles and the like, and a method of manufacturing the same.

As a tooth profile forming component for a transmission of an automobile, a product by cold press molding has recently been frequently used from the viewpoint of cost reduction. When manufacturing flanged bottomed tooth profile forming parts by cold press forming, first, a thin metal plate with a bottomed cylindrical flange with a flange at the end on the side away from the bottom by plastic working (drawing) Formed on intermediate coarse material (work). Next, the tooth profile portion is formed on the cylindrical portion of the workpiece by plastic working (tooth profile formation). When forming the external teeth, the plastic working die has a tooth shape on the inner periphery, and the part of the workpiece that hits the die shape of the die is pressed to the inner diameter side by press-fitting the die into the die. Since the side is restrained by the punch, the metal escapes by plastic flow in the axial direction, the portion of the cylindrical portion that contacts the tooth shape is formed in the tooth profile valley, and the tooth profile crest is left between the tooth profile valleys ( Patent Document 1).
Japanese Patent No. 2706257

  In the technique of Patent Document 1, when external teeth are formed on a workpiece with a flange, the root portion of the flange portion inevitably has an incomplete tooth profile. That is, the tip of the punch in the mold exhibits a relatively long tip taper portion (so-called run-up portion) with a gentle inclination to allow smooth introduction into the die. In a state where the punch is completely inserted into the die through the work, the tip of the punch is in contact with the bottom surface of the opposing flange, and the running portion, which is the tapered portion of the punch tip, contributes to the formation of the tooth profile for the work. Therefore, the part of the work formed by the running portion, that is, the base portion of the flange portion has a tapered shape, and the tooth profile of this portion forms an incomplete tooth profile having a tapered shape. Therefore, the effective tooth length in the tooth profile forming part (the length along the axis of the complete tooth profile part in the tooth profile part) is shortened only by the incomplete tooth profile part, and it is necessary if the axial length of the tooth profile forming part is not increased. As a result, the meshing performance (transmission performance) cannot be obtained, and this has been a bottleneck for downsizing. Here, the incomplete tooth profile means that the width (tooth width) and height (tooth height) deviate from normal values in the cross section of the tooth profile portion.

  In view of the problems of the prior art, the present invention can increase the relative length of the complete tooth profile portion of the flanged tooth profile forming part, while maintaining the required meshing performance, and the relative axial dimensions of the flange tooth profile forming part. The purpose is to reduce the size.

According to the first aspect of the present invention, the cylindrical coarse material formed of the metal plate material is distributed on the outer peripheral surface of the cylindrical coarse material at equal intervals over the entire length in the circumferential direction, each from one end side to the other end of the cylindrical coarse material. Forming a plurality of tooth profile portions extending to the other end while leaving a non-processed portion, and cutting the portion of a predetermined width on the outer periphery of the cylindrical coarse material so that the tooth profile portion is a complete tooth profile on the cutting end surface Provided is a method for manufacturing a flanged tooth profile forming part, wherein a flange portion facing the cutting end surface of the tooth profile portion is formed by bending the cutting portion of the cylindrical coarse material after the end. Is done.

According to the invention described in claim 2 , in the invention described in claim 1 , in the bending process of the cylindrical coarse material, the transition portion to the flange portion at the cutting site of the cylindrical coarse material presents an annular protrusion. A method for manufacturing a flanged tooth profile forming part characterized by being bent as much as possible is provided.

According to a third aspect of the present invention, there is provided a method for manufacturing a flanged tooth profile forming part according to the first or second aspect , wherein the plurality of tooth profile portions are formed by plastic working. The

According to a fourth aspect of the present invention, there is provided a method for manufacturing a flanged tooth profile forming part according to the first or second aspect , wherein the plurality of tooth profile portions are formed by cutting. The

The operation and effect of the invention of claim 1 will be described. After the tooth profile is formed on the cylindrical coarse material, the end of the tooth profile facing the flange portion is cut by cutting a predetermined width portion of the cylindrical coarse material. The part of the incomplete tooth profile can be deleted. Then, by bending the cut portion of the cylindrical coarse material into a flange portion, the end surface of the tooth profile portion facing the flange portion can be made into a complete tooth profile, and a bending process for forming the flange portion can be performed as desired. By performing in position, the positional relationship between the end face of the tooth profile part and the flange part can be set as desired, and the required meshing performance required for the part is secured while the part is set to the required axial dimension. can do.

The operation and effect of the invention of claim 2 will be described. Since the annular protrusion is bent at the transition portion to the flange portion at the cutting site of the cylindrical coarse material, the region inside the bag-shaped portion in the tooth profile forming component Can function as an oil reservoir weir, and since it is a bending process for a thinned cutting part, a high-quality bending process can be performed at a low cost, which can contribute to a cost reduction.

The operation and effect of the invention of claim 3 will be described. By forming the tooth profile portion by plastic working, the manufacturing cost can be reduced while maintaining the required accuracy.

The operation and effect of the invention of claim 4 will be described. By forming the tooth profile portion by cutting with a tool, a tooth profile forming component with higher accuracy can be obtained.

  Referring to the drawings, the flanged tooth forming part of the present invention is intended for use in an automobile transmission or the like, and is made of a metal plate material (such as a steel plate). A steel plate having a predetermined thickness can be formed into a bottomed cylindrical coarse material (hereinafter referred to as a workpiece) indicated by reference numeral 10 in FIG. 1 by plastic working (drawing) using a press device. The workpiece 10 includes a cylindrical section 10-1 having a circular cross section, a circular bottom 10-2 at one end of the cylindrical section 10-1, and a boss 10-3 at the center of the bottom 10-2.

  Next, the workpiece 10 is subjected to a tooth profile forming step by plastic working. In FIG. 2, the mold for forming the tooth profile is constituted by a punch 12 and a die 14. The punch 12 can be installed on the head side of the press device, for example, and the die 14 can be installed on the die cushion side of the press device. The punch 12 has an outer diameter fitted to the inner diameter 10A of the cylindrical portion 10-1 of the workpiece 10, and a cavity 12A is opened on the bottom surface of the punch 12, and the cavity 12A of the punch 12 is a boss of the workpiece 10. It has an inner diameter that can accommodate the portion 10-3. On the other hand, the die 14 has a circular section bottomed cavity 14A fitted to the outer diameter of the cylindrical portion 10-1 of the workpiece 10, and the die 14 is formed on the inner peripheral surface of the circular section bottomed cavity 14A. Each extends in the axial direction, and has a plurality of tooth-shaped portions 16 as projections spaced in the circumferential direction. Each tooth portion 16 extends along the axis of the workpiece 10 from one end 16-1 in the axial direction on the inner circumferential surface of the circular section bottomed cavity 14A to the other end 16-2 on the bottom side of the circular section bottomed cavity 14A. Extending along. The tooth-shaped portion 16 has a tapered shape with a relatively gentle inclination angle at one end 16-1, that is, at the introduction side end of the punch 12 with respect to the die 14, in both the width direction and the height direction. -1 is referred to as a so-called run-up portion, and such a run-up portion is necessary for smooth press working (smooth introduction of the workpiece 10 into the die 14).

  FIG. 2B shows a state where the punch 12 is pushed into the die 14 via the workpiece 10 (a state where the punch 12 and the die 14 are combined). That is, the punch 12 is fitted to the cylindrical portion 10-1 of the workpiece 10 at the outer diameter, and the punch 12 is introduced into the cavity 14A of the die 14 with the workpiece 10 fitted at the outer diameter. At this time, the tapered end portion 16-1 (running portion) at the punch introduction side end of the tooth mold portion 16 can be used for smooth introduction of the workpiece 10. Finally, the bottom surface of the punch 12 presses the bottom surface 10-2 of the workpiece 10 against the opposite bottom surface of the die 14, and the boss portion 10-3 of the workpiece 10 is accommodated in the cavity 12A opened in the bottom surface of the punch 12. (B) is reached. The tooth mold portion 16 of the die 14 presses the cylindrical portion 10-1 of the workpiece 10 from the outer periphery to cause plastic deformation, and teeth are formed on the cylindrical portion 10-1 of the workpiece 10 in contact with the tooth mold portion 16 of the die 14. A plurality of tooth profile valleys 18 (FIG. 3) having a shape complementary to the part 16 are formed at equal intervals in the circumferential direction, and a tooth profile peak 20 is formed between the tooth profile valleys 18. And the tooth profile crest 20 are collectively referred to as a tooth profile. The surplus metal material due to the formation of the tooth profile valley portion 18 escapes backward in the annular gap between the punch 12 and the die 14 having the minimum flow resistance. The direction of this plastic flow is indicated by an arrow a in FIG. Therefore, the outer diameter and the inner diameter of the workpiece 10 are not substantially changed (thickness is maintained) as compared with before the press working is completed, but the axial length thereof is from 1A (FIG. 2 (A)) to 1B (FIG. 2). 2 (b)). FIG. 3 (a) shows the cross-sectional shape of the workpiece 10 taken out from the mold after press working, and (b) shows a perspective view. As shown in FIG. 3 (b), the tooth profile valley portions 18 are formed on the outer peripheral surface of the cylindrical portion 10-1 of the workpiece 10 at equal intervals in the circumferential direction, and each tooth profile valley portion 18 is a bottom portion of the workpiece 10. It extends along the axis of the workpiece 10 from the first end 18-1 on the 10-2 side, and terminates at the second end 18-2 in the middle portion of the cylindrical portion 10-1 of the workpiece 10 in the axial direction. ing. That is, the open end side from the other end 18-2 of the tooth profile valley portion 18 in the cylindrical portion 10-1 of the workpiece 10 remains as an unprocessed portion 10-1A having no tooth profile portions (the tooth profile valley portion 18 and the tooth profile mountain portion 20). Has been. As already described with reference to FIG. 2 (a), the tooth mold part 16 of the die 14 forming the tooth profile valley part 18 has a relatively long taper shape with a gentle slope at the end 16-1 (running part) on the punch introduction side. There is no. Therefore, the tooth profile valley portion 18 on the workpiece formed by the die 14 also follows the shape of the tooth mold portion 16, and the end portion 18-2 on the unprocessed portion 10-1A side extends both in the height direction and in the width direction. (The tooth profile valley portion 18 is smoothly connected to the cylindrical portion 10-1 while being tapered). Because of the shape of the tooth profile valley 18 which is tapered at the second end 18-2 on the side of the run-up portion, the tooth profile crest 20 is in the height direction and width direction at the end 20-2 on the unprocessed portion 10-1A side. While expanding, it has a shape that is continuous with the cylindrical portion 10-1, and at the end portions 18-2 and 20-2, both the tooth profile valley portion 18 and the tooth profile peak portion 20 exhibit incomplete tooth profile portions. In this embodiment, the first end 20-1 of the tooth profile 20 extends flush with the bottom surface 10-2 of the workpiece 10, but the portion separated from the workpiece bottom surface 10-2 is a portion of the tooth profile 20 that is somewhat separated. The starting point is also included in the present invention.

  FIGS. 4 (a) and 4 (b) show the cutting process of the incomplete tooth profile after press forming the tooth profile on the outer peripheral surface of the cylindrical portion 10-1 of the workpiece 10. FIG. That is, in this process, the outer peripheral surface of the cylindrical portion 10-1 after the press forming of the tooth profile portion on the workpiece 10 is cut by the thickness d from the open side end surface at the portion of the axial length of L, and the thinned cylindrical portion 10 is thinned. -1B (the inner diameter 10A of the workpiece 10 remains straight). The axial length L at which cutting is performed includes at least the tooth profile valley portion 18 of the tooth profile portion and the incomplete tooth profile portions 18-2 and 20-2 (FIG. 3A) of the tooth profile peak portion 20 after the press forming of the tooth profile. In addition, the thickness d (cutting depth) is such that the cutting surface is at least in the vicinity of or deeper than the tooth bottom surface (the bottom surface of the tooth profile valley portion 18). Therefore, the incomplete tooth profile portions 18-2 and 20-2 at the rear ends of the tooth profile valley portion 18 and the tooth profile peak portion 20 formed in the tooth profile press molding process of FIG. 3 are completely cut off, and the complete tooth profile end face 20-2A is obtained. It becomes. In this embodiment, the thickness d is excised uniformly from the tooth profile crest 20 side to the end face of the workpiece 10, but the present invention is not necessarily limited to such a excision method, and the tooth profile trough 18 and the tooth profile crest. Only 20 incomplete tooth profile portions may be cut into a strip shape (annular) with a thickness d, and the remaining portions may be cut without cutting or thinly cut. FIG. 4B is a perspective view of the workpiece 10 after excision after completion of the cutting process.

  FIGS. 5 (a) to 5 (c) show a flange forming process by bending. In FIG. 5 (b), which shows the first stage bending process, the thin-walled tubular portion 10 of the workpiece 10 shown in FIG. -1B is bent to a predetermined angle from the root portion P of the tooth profile portion 20 by using a taper-shaped punch (not shown), and is formed in the inclined flange portion 10-1C. FIG. 5 (b) shows the second stage bending process, wherein the inclined flange portion 10-1C of (a) is bent (flattened) until it becomes horizontal, and the horizontal flange portion 22 which is the final product. Can be obtained (see also the perspective view of FIG. 5 (c)). In the flanged bottomed tooth profile forming component 24 thus obtained, the tooth profile 20 terminates in a complete tooth profile at the flange end face 20-2A and the end surface 20-2A of the tooth profile 20 Is located close to the flange portion 22. If necessary, the tooth end 20-2A can be brought into contact with the flange portion 22. In the tooth profile forming component according to the present invention, the tooth profile (the tooth profile valley 18 and the tooth profile 20) terminates in a complete tooth profile at the end on the flange side. The effective tooth length can be increased while maintaining the thickness of the component 24 to be the same, and the miniaturization (reduction in the axial dimension) of the flanged tooth profile forming component 24 can be achieved while maintaining the required meshing performance. . Further, since the bending to the flange portion 22 is performed by the thinned cylindrical portion 10-1B, the bending process becomes easy.

  FIG. 6 (a) shows a case where the flange portion 22 is bent so as to be separated from the end face of the tooth profile portion 20, and the thinned cylindrical portion 10-1B (FIG. 4) after the incomplete tooth shape portion is cut off. ) Can be arbitrarily set to the size of the gap g from the flange portion 22 to the end face of the tooth profile ridge portion 20 by selecting the bending start position (P in FIG. 5A). It goes without saying that the axial dimension of the tooth profile forming part can be minimized when the distance g = 0, but it is possible to select a part having a desired axial dimension while maintaining the meshing performance by setting the value of the distance g. Obtainable.

  In FIG. 6 (b), the tooth-shaped part having the annular protrusion 22A on the flange portion 22 is obtained by bending the thinned cylindrical portion 10-1B of FIG. 4 into a bag shape.

  In FIG. 6C, the thinned cylindrical portion 10-1B of FIG. 4 is bent somewhat radially inward first and then bent radially outward to form the flange portion 22. An indentation 28 is formed in an annular shape inside by bending inward in the radius, and has a function of an oil reservoir weir (a lubricating oil reservoir for lubricating the meshing portion) when the component is used as a tooth profile forming component of an automobile transmission. Can be made.

  In FIGS. 6 (b) and 6 (c), the bag-like bending is performed by the cylindrical portion 10-1B which has been thinned by cutting, so that it is easy to form by press bending, and there is no additional part. It can be provided with an additional function such as an oil reservoir weir, which can contribute to a reduction in component costs.

  In the above embodiment, the formation of the tooth profile (tooth profile valley 18 and tooth profile 20) in the tooth profile forming component has been described with reference to FIG. 3 so as to be obtained by press molding (plastic working). The invention is not limited to press molding, but also includes mechanical cutting. That is, even in mechanical cutting, an incomplete tooth profile is formed at the introduction part of the tool, so that the incomplete tooth profile is removed by the same method as in FIG. By bending the thinned portion of the coarse material in the same way as in Fig. 5, the tooth profile can be made into a complete tooth profile up to the flange, ensuring the necessary meshing performance. However, it is possible to reduce the axial dimension of the component.

FIG. 1 is a view showing a cross-sectional shape of a cylindrical coarse material prior to formation of a tooth profile by press molding. FIG. 2 is a schematic view showing the steps (a) and (b) of forming a tooth profile portion by press molding on a cylindrical coarse material. FIG. 3 is a cross-sectional view (A) and a perspective view (B) of the cylindrical coarse material after the tooth profile is formed by press molding. FIG. 4 is a cross-sectional view (A) illustrating a cutting process for removing an incomplete tooth profile portion in the tooth profile and a perspective view of the cylindrical coarse material after the cutting process. 5A and 5B show the first and second stages of the bending process after partial cutting of the incomplete tooth profile in FIGS. 5A and 5B, and FIG. 5C is a perspective view of the flanged tooth profile forming part after the bending process is completed. is there. FIG. 5 shows various modified embodiments, (A) illustrates the clearance adjustment between the flange portion and the tooth profile portion during the bending process, and (B) is a case where the bending is performed in a bag shape. ) Is an oil reservoir weir formed on the inner peripheral side of the flanged tooth profile forming part.

Explanation of symbols

10 ... Cylinder with bottom
10-1 ... Cylindrical part
10-1A: Unprocessed part after forming tooth profile on cylindrical part
10-1B… Thinned cylindrical part to remove incomplete tooth profile
10-1C: Thin walled cylindrical part 12 subjected to the first stage bending to form a flange part ... Punch 14 ... Die 16 ... Die tooth part
16-1… Tapered end (running section)
18: Tooth profile valley formed on coarse material
18-1… One end of tooth profile valley
18-2 ... The other end 20 of the tooth profile trough ... The tooth profile crest
20-1… One end of tooth profile
20-2… The other end of the incomplete tooth profile of the tooth profile
20-2A ... Completely toothed other end 22 of the tooth profile part ... Flange part 28 ... Oil sump weir

Claims (4)

  The outer circumferential surface of the cylindrical coarse material formed of the metal plate material is distributed at equal intervals over the entire length in the circumferential direction, each of which has an unprocessed portion with respect to the other end from one end side to the other end of the cylindrical coarse material. A plurality of tooth profile portions extending to be left are formed, and a portion of a predetermined width on the outer periphery of the cylindrical coarse material is cut so that the tooth profile portion terminates in a complete tooth profile at the cutting end surface, and then the cylindrical coarse material A method for manufacturing a flanged tooth profile forming part, wherein the flange portion is positioned opposite to the cutting end surface of the tooth profile portion by bending the cutting portion. The invention according to claim 1 , wherein, in bending of the cylindrical coarse material, the transition portion to the flange portion at the cutting portion of the cylindrical coarse material is bent so as to exhibit an annular protrusion . Manufacturing method of tooth profile forming part. 3. A method for manufacturing a flanged tooth profile forming part according to claim 1 , wherein the plurality of tooth profile portions are formed by plastic working. 3. The method for manufacturing a flanged tooth profile forming part according to claim 1 , wherein the plurality of tooth profile portions are formed by cutting.

Images