JP5987714B2 - Metal workpiece processing method - Google Patents

Description

  The present invention provides a metal workpiece in which, after forming a ridge portion by rolling on a metal workpiece, a groove is formed on the top surface of the ridge portion so as to cross the ridge portion by pressing. It belongs to the technical field related to processing methods.

  Generally, when forming a clutch drum used in an automatic transmission of an automobile, spline teeth are formed on the inner peripheral surface of a metal cylindrical workpiece by rolling, and then all spline teeth are formed by pressing. A snap ring groove is formed on the top surface so as to cross the spline teeth. A snap ring is fitted into the groove for the snap ring. The snap ring prevents the clutch plate and the friction plate, which are alternately disposed in the axial direction, between the clutch drum and the clutch hub disposed inside the clutch drum and having spline teeth formed on the outer peripheral side. And receives the pressing force when the clutch plate and the friction plate are pressed to the snap ring side for mutual engagement.

  However, when forming the snap ring groove, the work material is pushed radially outward by pressing, so that the bottom wall surface portion of the snap ring groove portion formed by pressing (particularly, axial direction relative to the bottom wall surface portion). There is a possibility that a crack may occur at a boundary part between the part not adjacent to the part and not pushed in. In particular, if the depth of the snap ring groove is increased in order to increase the snap ring catch, cracks are more likely to occur. When such a crack occurs, when the pressing force acts on the side wall surface portion of the snap ring groove portion via the snap ring, the wall surface portion of the snap ring groove portion breaks, and the snap ring receives the pressing force. The problem of being unable to do so arises.

  Therefore, in Patent Document 1, for example, the outer periphery of the clutch drum from the opening end side of the clutch drum is formed on a part of the shelf-like surface formed on the back side (radially outer side) of the snap ring contact portion in the clutch drum. By projecting the thick part extending toward the wall, a beam structure is formed between the clutch drum opening end side wall part and the shelf part in the snap ring groove part, and cracks are formed in the thick part. It prevents it from occurring.

JP 2000-257648 A

  If the thick portion as in Patent Document 1 is formed, it is possible to prevent the wall surface portion of the snap ring groove portion from being broken by the thick portion. The present inventors have found a method capable of obtaining such an effect without forming the film.

  The present invention has been made in view of such points, and the object of the present invention is to form a protrusion on a metal workpiece by rolling, and then press the top surface of the protrusion. Thus, when the groove is formed so as to cross the protrusion, even if a pressing force acts on the side wall surface of the groove in the width direction of the groove, the wall surface of the groove is prevented from breaking. There is.

In order to achieve the above object, in the present invention, after forming a ridge portion by rolling on a metal workpiece, the top surface portion of the ridge portion is crossed by the press processing. For the method of processing a metal workpiece that forms a groove, at the same time as forming the protrusion on the metal workpiece by rolling, at the same time, at least in the widthwise central portion of the top surface of the protrusion in the groove forming area of the concave portion forming step of forming a recess having a predetermined depth depth below the groove portion, after the recess forming step, the forming schedule of the groove area at the top surface of the ridge And a groove portion forming step of forming the groove portion by press working.

By the method described above, in the concave portion forming step, at least the groove forming region of a widthwise central portion of the top wall of the ridge, recess is formed, thereafter, in the groove forming step, the top surface of the ridge the formation region of the groove in the groove is formed by pressing.

  Since the concave portion is formed simultaneously with the formation of the protruding portion by rolling, no crack is generated in the wall surface portion of the concave portion. In addition, since the concave portion is formed in the central portion in the width direction of the top surface portion of the ridge portion, the concave portion is formed even if the side surfaces on both sides in the width direction of the ridge portion are engaging surfaces that engage with other members. However, it does not adversely affect both side surfaces of the protrusion in the width direction.

The groove portion is formed in a region where the groove portion is to be formed on the top surface portion of the ridge portion and in a region on both sides in the width direction of the ridge portion with respect to the recessed portion formation region (width direction center portion). . In the recessed portion forming region, the amount of pushing for forming the groove portion by press working may be small. In particular, if the recess has the same depth as the groove, the amount of pushing will be zero. As a result, by appropriately setting the predetermined depth of the concave portion, in the portion corresponding to the concave portion formation region in the bottom wall surface portion of the groove portion, it is possible to ensure the connection of the material along the direction in which the ridge portion extends, Cracks can be prevented from occurring. On the other hand, in the both sides in the width direction of the region of the ridges relative to the recess forming region in the forming region of the groove, the pressing amount for groove formation by press working the same as the depth of the groove bottom of the groove wall portion Cracks may occur in portions corresponding to both side regions of the recess formation region (especially, a boundary portion with a portion not pressed in adjacent to the portion in the direction in which the protruding portion extends). Even if it occurs, since the crack does not occur in the portion corresponding to the recess forming region in the bottom wall surface portion of the groove portion, the strength of the entire wall surface portion of the groove portion is ensured, and the wall surface portion of the groove portion is pushed in the width direction of the groove portion. Even when pressure acts, it is possible to prevent the wall surface of the groove from breaking. Note that the side wall surface portion of the groove portion does not exist in the portion corresponding to the concave portion formation region or the height thereof is low, so the above pressing force basically corresponds to both side regions of the concave portion formation region in the side wall surface portion of the groove portion. However, since the strength of the entire wall surface portion of the groove portion is ensured as described above, the wall surface portion of the groove portion is not broken.

  According to an embodiment of the present invention, the metal workpiece is a cylindrical workpiece, the protruding portion is a plurality of spline teeth formed on an inner peripheral surface of the cylindrical workpiece, and the groove portion is , A snap ring groove formed on the top surface of the plurality of spline teeth and fitted with a snap ring.

  As a result, a member having spline teeth and a snap ring groove, such as a clutch drum, can be easily formed, and a pressing force is applied in the axial direction to the snap ring fitted in the snap ring groove. Sometimes, the pressing force can be received stably.

As described above, according to the method for processing a metal workpiece of the present invention, at the same time as forming the ridge portion on the metal workpiece by rolling, at least the widthwise central portion of the top surface portion of the ridge portion, A recess is formed in the region where the groove is to be formed, and then the groove is formed by pressing in the region where the groove is to be formed in the top surface of the ridge, thereby pushing the side wall surface of the groove in the width direction of the groove. Even when pressure acts, it is possible to prevent the wall surface of the groove from breaking.

It is a perspective view which shows the metal clutch drum manufactured by the processing method which concerns on embodiment of this invention. It is the elements on larger scale which looked at the clutch drum from the open end side of the cylindrical part. It is the schematic which shows the process of forming a spline tooth and a recessed part in a workpiece | work by rolling. It is the schematic which shows the process of forming the groove part for snap rings in a workpiece | work by press work. It is the VV sectional view taken on the line of FIG. It is the VI-VI sectional view taken on the line of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a metal clutch drum 1 manufactured by a processing method according to an embodiment of the present invention. The clutch drum 1 has a bottomed cylindrical shape with one end opened, and a shaft hole 10 through which a shaft member that supports the clutch drum 1 passes is provided at the bottom. On the inner circumferential surface of the cylindrical portion of the clutch drum 1, a plurality of spline teeth 11 as ridge portions extending in the axial direction of the cylindrical portion and projecting inward are arranged at equal intervals in the circumferential direction of the cylindrical portion. It is formed as follows. A spline groove 12 is formed between two adjacent spline teeth 11.

  Near the open end of the inner peripheral surface of the cylindrical portion of the clutch drum 1, a snap ring groove portion 14 (hereinafter referred to as a groove portion 14) into which the snap ring is fitted is formed. The groove portion 14 extends in the circumferential direction of the cylindrical portion and is provided over the entire inner peripheral surface of the cylindrical portion. However, since the depth of the groove portion 14 does not reach the spline groove 12, Is provided only on the spline teeth 11. The groove portion 14 extends in the circumferential direction of the cylindrical portion so as to cross each spline tooth 11 extending in the axial direction of the cylindrical portion. In addition, a protrusion 15 generated when the groove 14 is formed as described later is formed in a portion of the outer peripheral surface of the cylindrical portion corresponding to a region where the concave portion 17 is not formed in the bottom wall surface of the groove 14. .

  The snap rings are arranged alternately between the clutch drum 1 and the clutch hub disposed inside the clutch drum 1 and having spline teeth formed on the outer peripheral side thereof in the axial direction of the cylindrical portion. The clutch plate and the friction plate are pressed against the snap ring for engagement with each other to receive the pressing force. One of the clutch plate and the friction plate is engaged with the spline teeth of the clutch drum 1 so as to be movable in the axial direction of the cylindrical portion, and the other is engaged with the spline teeth of the clutch hub so as to be movable in the axial direction of the cylindrical portion. When the clutch plate and the friction plate are engaged with each other, the clutch drum 1 and the clutch hub rotate together.

  In this embodiment, as shown in FIGS. 1 and 2, the center in the tooth thickness direction (circumferential direction of the cylindrical portion) of the tip surface portion of each spline tooth 11, that is, the center in the width direction at the top surface portion of the ridge portion. A groove-like recess 17 extending in the axial direction of the cylindrical portion is formed in the portion. In this embodiment, the concave portion 17 extends from the open end of the cylindrical portion to the bottom side beyond the groove portion 14. The concave portion 17 is formed in the tooth thickness direction central portion (the central portion in the width direction at the top surface portion of the ridge portion) at the tip surface portion of the spline teeth 11 simultaneously with the spline teeth 11 by rolling before forming the groove portion 14. The groove 14 is formed on the both sides in the axial direction of the cylindrical portion. The concave portion 17 has a predetermined depth equal to or less than the depth of the groove portion 14 (in this embodiment, the same depth as the depth of the groove portion 14).

  An oil hole (not shown) is formed in a part of the plurality of spline grooves 12 (on the bottom side of the groove portion 14 in the axial direction of the cylindrical portion). Automatic transmission oil (ATF) is discharged out of the cylindrical portion of the clutch drum 1.

  Next, a method for manufacturing the clutch drum 1 will be described.

  First, as shown in FIG. 3A, a metal workpiece W, which is a subject to be subjected to a rolling process, is manufactured by subjecting a metal plate to punching and drawing using a pressing device (not shown). The work W has a bottomed cylindrical shape that is a basic shape of the clutch drum 1, and a shaft hole 10 is formed at the bottom of the work W. The axial length of the cylindrical portion of the workpiece W is shorter than the completed dimension, and the cylindrical portion has an excessive plate thickness.

  Subsequently, as shown in FIG. 3B, spline teeth 11 and spline grooves 12 are formed on the inner peripheral surface of the cylindrical portion of the workpiece W by rolling. This rolling process is performed by the spline forming apparatus 20. The spline forming apparatus 20 includes a mandrel 21 having an outer peripheral portion 21a provided with a plurality of tooth portions corresponding to the spline teeth 11 and convex portions corresponding to the concave portions 17 provided on the tooth tip surfaces of the respective tooth portions. And a rolling roller 22 having a protrusion having a tooth shape on the outer peripheral surface.

  The rolling roller 22 is rotatably supported by the rotary head 23 and can be rotated in the r1 direction so as to rotate about the rotation axis of the rolling roller 22 itself, and the mandrel 21 is rotated by the rotation of the rotary head 23. , While rotating close to and away from each other, it can rotate in the r2 direction so as to revolve around the rotation shaft 23a of the rotary head 23. Further, two rolling rollers 22 (may be one rolling roller 22) are supported with respect to one rotating head 23, and the rotating head 23 faces the mandrel 21 in the radial direction. Thus, a pair (two) is arranged, and the pair of rotary heads 23 can rotate in opposite directions. One rotating head 23 may be provided.

  In order to form the spline teeth 11 on the workpiece W by the spline forming apparatus 20, first, the mandrel 21 is inserted inside the cylindrical portion of the workpiece W, and the workpiece W is fixed to the mandrel 21 by the fixture 24 (FIG. 3). (See (b)).

  Subsequently, the cylindrical portion of the workpiece W is moved by the protrusion of the rolling roller 22 while the revolution period of the rolling roller 22 is synchronized with the feed amount and feed speed of the mandrel 21 in the axial direction d1 and the circumferential direction d2. By pressing against the outer peripheral portion 21a, the spline teeth 11 and the concave portion 17 are simultaneously formed between the protruding portion of the rolling roller 22 and the outer peripheral portion 21a of the mandrel 21. The concave portion 17 has the same depth as the depth of the groove portion 14, and is the central portion in the tooth thickness direction of the tooth tip surface portion of the spline tooth 11, and the work W with respect to the formation planned region and the planned formation region of the groove portion 14. Are formed on both sides of the cylindrical portion in the axial direction.

  Next, the groove portion 14 is formed by pressing in the region where the groove portion 14 is to be formed in the tip surface portion of the spline teeth 11, and oil holes are formed in some of the spline grooves 12. Further, the portion other than the effective range on the open end side of the workpiece W is cut. That is, during the rolling process by the spline forming apparatus 20, the workpiece W is deformed so as to extend in the axial direction and the circumferential direction of the cylindrical portion, and thus the portion extending in the axial direction is cut off. Note that the amount of elongation of the work W in the circumferential direction is predicted in advance by a test or the like, and the shape of the outer peripheral portion 21a of the mandrel 21 is determined in consideration of the predicted amount of elongation. Thus, the clutch drum 1 is completed.

  The groove 14 is formed by a die 30 and a punch 40 as shown in FIGS. The die 30 is located radially outside the cylindrical portion of the workpiece W placed on a rotary table (not shown), and is separated from or in contact with the workpiece W by a driving mechanism (not shown) (the cylindrical portion of the workpiece W). (Radial direction). The die 30 has a shape corresponding to the unevenness of the cylindrical portion of the workpiece W when viewed from the axial direction of the cylindrical portion of the workpiece W, and can be substantially in close contact with the outer peripheral surface of the cylindrical portion of the workpiece W. A concave portion 30a (see FIG. 6) is formed on the surface of the die 30 that is substantially in close contact with the outer peripheral surface of the cylindrical portion of the workpiece W, corresponding to the protruding portion 15 that protrudes when the groove portion 14 is formed. On the other hand, the punch 40 is located on the radially inner side of the cylindrical portion of the workpiece W, and can be moved in a direction to come in contact with the workpiece W (the radial direction of the cylindrical portion of the workpiece W) by a drive mechanism (not shown). It is. When the die 30 is in close contact with the outer peripheral surface of the cylindrical portion of the workpiece W, the punch 40 is the inner peripheral surface of the cylindrical portion of the workpiece W (planned formation region of the groove portion 14 in the tip surface portion of the spline teeth 11). To form the groove 14 in the region where the groove 14 is to be formed in the tip surface portion of the spline tooth 11.

  In this embodiment, the groove part 14 is formed in the tooth tip surface part of the two spline teeth 11 at a time. After forming the groove portion 14 in the two spline teeth 11, the die 30 and the punch 40 are separated from the workpiece W, and then the rotary table is rotated so that the next two spline teeth 11 are located between the die 30 and the punch 40. Then, the grooves 14 are simultaneously formed in the next two spline teeth 11 by the die 30 and the punch 40 in the same manner as described above. By repeating this operation, the groove portions 14 are formed in all the spline teeth 11, and thus the formation of the groove portions 14 is completed.

  In the formation of the groove portion 14, in the region where the recess portion 17 is not formed in the region where the groove portion 14 is to be formed (regions on both sides in the tooth thickness direction of the spline teeth 11 with respect to the recess portion 17), the groove portion 14 is formed by pressing. The pushing amount for this is the same as the depth of the groove 14, and as shown in FIG. 6, the bottom wall surface of the groove 14 protrudes outward in the radial direction of the cylindrical portion of the workpiece W to form a protrusion 15. At this time, the portion corresponding to the region where the concave portion 17 is not formed in the bottom wall surface portion of the groove portion 14 (protrusion portion 15), in particular, is not pushed adjacent to the protrusion portion 15 in the axial direction of the cylindrical portion of the workpiece W. There is a possibility that a crack may occur at a boundary portion with the portion (a portion marked with x in FIG. 6). If the concave portion 17 is not formed before the formation of the groove portion 14, the entire circumferential direction of the bottom wall surface portion of the groove portion 14 protrudes radially outward, and therefore, over the entire circumferential direction of the bottom wall surface portion of the groove portion 14, It becomes difficult to ensure the connection of the material along the axial direction of the cylindrical portion of the workpiece W.

  On the other hand, in this embodiment, the concave portion 17 is formed before the groove portion 14 is formed, and in the region where the groove portion 14 is to be formed, in the formation region of the concave portion 17, the amount of pressing for forming the groove portion 14 by press working Is 0 (see FIG. 5). As a result, a portion corresponding to the formation region of the recess 17 in the bottom wall surface portion of the groove portion 14 (this portion is pulled by the protruding portions 15 on both sides thereof and slightly protrudes radially outward (FIG. 5). In FIG. 2 and FIG. 4, the protrusion is omitted, but in FIG. 2 and FIG. 4)), the connection of the material along the axial direction of the cylindrical portion of the workpiece W can be secured, and a crack occurs. Can be prevented. Thereby, even if a crack occurs in a portion (projecting portion 15) corresponding to a region where the concave portion 17 is not formed in the bottom wall surface portion of the groove portion 14, the strength of the entire wall surface portion of the groove portion 14 is ensured. Therefore, even if a pressing force acts on the side wall surface portion of the groove portion 14 in the width direction of the groove portion 14 (the axial direction of the cylindrical portion of the clutch drum 1) via the snap ring fitted in the groove portion 14, the groove portion 14 It is possible to prevent the wall portion from breaking.

  In addition, since the recessed part 17 is formed simultaneously with formation of the spline tooth | gear 11 by a rolling process, a crack does not arise in the wall surface part of the recessed part 17. FIG. Moreover, since the recessed part 17 is formed in the tooth thickness direction center part in the tooth tip surface part of the spline tooth 11, the formation of the recessed part 17 is an engagement surface (spline tooth 11) with the clutch plate or the friction plate in the spline tooth 11. (Surfaces located on both sides in the tooth thickness direction) with respect to the tooth tip surface portion) (for example, the engagement surface is not deformed).

  The present invention is not limited to the embodiment described above, and can be substituted without departing from the spirit of the claims.

  For example, in the above embodiment, the depth of the concave portion 17 is the same as the depth of the groove portion 14, but the concave portion 17 may be a predetermined depth equal to or less than the depth of the groove portion 14. The predetermined depth may be set such that when the groove 14 is formed by pressing, a crack does not occur in a portion corresponding to the formation region of the recess 17 in the bottom wall surface portion of the groove portion 14. When the depth of the concave portion 17 is shallower than the depth of the groove portion 14, in the side wall surface portion of the groove portion 14, in addition to the portion corresponding to the region where the concave portion 17 is not formed, the portion corresponding to the formation region of the concave portion 17 In addition, a pressing force acts in the width direction of the groove portion 14 via the snap ring, and the pressing force can be dispersed.

  Moreover, in the said embodiment, the recessed part 17 is the tooth thickness direction center part in the tip surface part of the spline tooth | gear 11, Comprising: The formation area of the groove part 14, and the axial direction both sides of the cylindrical part of the workpiece | work W with respect to this formation area Although formed in the portion, the concave portion 17 may be formed at the central portion in the tooth thickness direction of the tip surface portion of the spline tooth 11 and at least in the region where the groove portion 14 is to be formed. However, in order to remove the mandrel 21 from the inside of the cylindrical portion of the workpiece W after the rolling process, the concave portion 17 is opened in the axial direction of the cylindrical portion of the workpiece W with respect to the formation planned region of the groove portion 14 and the planned forming region. It is preferable to form on the end side. If the convex portion for forming the concave portion 17 is configured to be able to advance and retreat in the outer peripheral portion 21a of the mandrel 21, the concave portion 17 is formed only in the region where the groove portion 14 is to be formed at the central portion in the tooth thickness direction of the tip surface portion of the spline tooth 11. It is also possible to form it.

  Furthermore, in the above-described embodiment, the present invention is applied to the manufacture of the clutch drum 1, but in the present invention, the spline teeth and the snap ring groove portion into which the snap ring is fitted are formed on the inner peripheral surface of the cylindrical portion. It can be applied to members. Moreover, after forming a protrusion part by rolling in a metal workpiece, it is manufactured by forming a groove part across the protrusion part by pressing on the top surface part of the protrusion part. The present invention can be applied to anything as long as it is present.

  The above-described embodiments are merely examples, and the scope of the present invention should not be interpreted in a limited manner. The scope of the present invention is defined by the scope of the claims, and all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  The present invention provides a metal workpiece in which, after forming a ridge portion by rolling on a metal workpiece, a groove is formed on the top surface of the ridge portion so as to cross the ridge portion by pressing. Useful for processing methods.

W Metal workpiece 1 Clutch drum 11 Spline teeth (ridge)
14 Snap ring groove 17 Recess

Claims (2)

This is a method for processing a metal workpiece, in which after a protrusion is formed on a metal workpiece by rolling, a groove is formed on the top surface of the protrusion by a press process so as to cross the protrusion. And
At the same time as forming the ridges on the metal workpiece by rolling, at the center of the width direction of the top surface of the ridges, at least in the region where the groove is to be formed, the depth of the groove or less A recess forming step for forming a recess having a predetermined depth;
After the said recessed part formation process, the groove part formation process which forms the said groove part by press work in the formation plan area | region of the said groove part in the top surface part of the said protrusion part includes the metal workpiece processing method characterized by the above-mentioned. In the processing method of the metal workpiece of Claim 1,
The metal workpiece is a cylindrical workpiece,
The protrusions are a plurality of spline teeth formed on the inner peripheral surface of the cylindrical workpiece,
The above-mentioned groove part is a groove part for snap rings formed in the top face part of a plurality of above-mentioned spline teeth, and a snap ring is fitted, The processing method of a metal work characterized by things.

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