JP2010172916A - Method and system for forming workpiece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and system for forming a workpiece, by which a product provided with a widespread thickened part and a widespread thin thickness part is formed inexpensively and easily. <P>SOLUTION: The method for forming the workpiece has: a first stage (S1) where the thickness in the middle part is reduced by applying drawing by using a nearly semispherical punch in the middle part of the planar workpiece of a fixed plate thickness; a second stage (S2) where the thickness in the periphery of the middle part is reduced and also a body part is thickened by applying ironing from the periphery of the middle part of the workpiece toward the body part on the outside; a third stage (S3) where the middle part is formed into nearly planar shape by crushing from the middle part of the workpiece to the periphery of the middle part in the plate thickness direction and also forming is performed so as to widen at nearly constant inclined angle from the periphery of the middle part toward the body part; a fourth stage (S4) where the workpiece is formed into nearly planar shape by crushing the whole workpiece in the plate thickness direction and a fifth stage (S5) where the final shape is formed on the basis of the workpiece formed into the nearly planar shape by the fourth stage (S4). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a workpiece forming method and a forming system.

A press working method for partially increasing the thickness of a workpiece to be processed is known (see Patent Document 1). Patent Document 1 discloses a technique for increasing the thickness of an end portion of a plate-like workpiece.
JP 2001-314921 A

  However, in the press working method disclosed in the above-mentioned Patent Document 1, the portion where the thickness can be increased is limited to the narrow range of the end portion of the workpiece and its periphery, and the workpiece cannot be increased over a wide range. . On the other hand, a coining process for reducing the thickness of the workpiece is also known, but this coining process cannot reduce the workpiece thickness over a wide range. In other words, if it is attempted to reduce the thickness over a wide range, a molding load of several thousand to several tens of thousands of tons is required, resulting in problems of mechanical equipment and mold life.

  For this reason, it is difficult to form a product having a wide range of thick parts and a wide range of thin parts (for example, a cover for a torque converter having a wide range of thick parts at the end of the cover and a wide range of thin parts at the center of the cover). There was a problem that there was.

  The present invention has been made in view of such a technical problem, and provides a molding method and a molding system for a workpiece that can easily and inexpensively mold a product having a wide-thick portion and a wide-thin portion. With the goal.

  The present invention is a method of forming a workpiece from a plate-shaped workpiece having a constant plate thickness, and forming a final shape with thickened ends, and drawing using a substantially hemispherical punch at the center of the workpiece The first step of reducing the thickness of the central portion by applying, and by ironing from the peripheral edge of the central portion of the workpiece toward the outer body portion, the peripheral edge of the central portion is reduced and the A second step of increasing the thickness of the body part, and by crushing in the plate thickness direction from the center part of the workpiece to the periphery of the center part, the center part is formed into a substantially flat shape and from the periphery of the center part to the body part. A third step of forming the workpiece so as to expand at a substantially constant inclination angle, and a reduced central portion, a peripheral portion of the central portion, and a thickened barrel portion by crushing the entire workpiece in the thickness direction. The entire workpiece is almost flat A fourth step of forming the Jo, based on the fourth molded into a substantially planar shape by the process work, and having a fifth step of forming the final shape.

  Further, the present invention is a workpiece molding system that molds a final shape with a thickened end from a plate-shaped workpiece having a constant thickness, using a substantially hemispherical punch at the center of the workpiece. The first processing means for reducing the thickness of the central portion by performing drawing and the ironing processing from the peripheral portion of the central portion of the workpiece toward the outer body portion, thereby reducing the peripheral portion of the central portion. The second processing means for increasing the thickness of the body portion, and crushing in the thickness direction from the center portion of the workpiece to the periphery of the center portion, thereby forming the center portion into a substantially flat shape and from the periphery of the center portion Third processing means that is shaped so as to expand toward the body portion at a substantially constant inclination angle, and the whole part of the work is crushed in the plate thickness direction to reduce the thickness of the central part, the peripheral part of the central part, and the thickness. Equipped with a torso A fourth processing means for forming the entire workpiece into a substantially flat shape, and a fifth processing means for forming the final shape based on the work formed into a substantially flat shape by the fourth processing means. It is characterized by having.

  According to the present invention, in the first step and the second step (the first processing means and the second processing means), the central portion and the peripheral portion of the workpiece can be formed without using a coining process that requires a large molding load. Since the thickness of the workpiece is reduced and the thickness of the body of the workpiece is increased, a product having a wide range of thick parts and a wide range of thin parts can be formed inexpensively and easily.

  Further, in the third step and the fourth step (the third processing means and the fourth processing means), since the space between the center portion of the workpiece and the periphery of the center portion is expanded step by step, Generation | occurrence | production of buckling in the center part periphery can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In this embodiment, a case where the work forming method according to the present invention is applied to forming a torque converter cover 2 (see FIG. 1) will be described as an example.

(About torque converter cover 2)
FIG. 1 is a schematic cross-sectional view of a torque converter cover 2 formed by the work forming method according to the present embodiment. The torque converter cover 2 will be described with reference to FIG.

  A torque converter cover 2 shown in FIG. 1 is one of the components of a torque converter 1 mounted on a vehicle such as an automobile. The torque converter cover 2 is a substantially bottomed cylindrical cover that houses a lockup clutch 4, a turbine runner (not shown), a stator (not shown) and the like between the pump impeller 3. The material is steel plate.

  Here, the torque converter cover 2 is divided into a thin portion 2a, a thick portion 2b, and an end portion 2c depending on the portion. The thin-walled portion 2a is a portion that has been thinned (thinned) to reduce the weight and size of the torque converter cover 2 (the thickness of the thin-walled portion 2a is, for example, 4.4 ± 0.5 mm). The thick portion 2b has been thickened (thickened) in order to reduce conduction of heat generated when the lock-up clutch 4 moves in the direction of the arrow in FIG. 1 and is pressed against the thick portion 2b. It is a part (the thickness of the thick part 2b is 7.6 mm, for example). The end portion 2 c is a portion located on the outer peripheral side of the torque converter cover 2. The torque converter cover 2 is joined to the pump impeller 3 at the end 2c (the thickness of the end 2c is, for example, 7.0 mm).

  As described above, the torque converter cover 2 includes the thick portion 2b that is thickened within a range that reduces the conduction of heat generated by the pressing of the lockup clutch 4 inside the end portion 2c. It is formed into a shape including a thin portion 2a that is thinned to the extent that the cover can be made lighter and more compact on the inner side than the thick portion 2b.

(About the outline of the molding process of the torque converter cover 2)
FIG. 2 is a flowchart showing a molding process of the torque converter cover 2 according to the present embodiment. FIG. 3 shows a cross-sectional view of the shape of the torque converter cover 2 in each step of FIG. The outline of the molding process of the torque converter cover 2 will be described with reference to FIGS. Details of the molding process will be described later.

  First, as a previous stage (step S0), a workpiece 5 to be machined is prepared. The workpiece 5 is a disk-shaped steel plate formed with a constant plate thickness (for example, 7 mm) (see FIG. 3 (S0)).

  If it progresses to step S1, the drawing process which thins the center part 5a of this workpiece | work 5 will be given. Thereby, the central part 5a is formed into a simple curved shape (see FIG. 3 (S1)) swelled upward. At this time, the central portion 5a of the workpiece 5 is thinned (4.4 mm ± 0.5 mm in this example).

  If it progresses to step S2, the ironing process which thins the center part periphery 5b of this workpiece | work 5 will be given. Thereby, the center part peripheral edge 5b is shape | molded in the shape (refer FIG. 3 (S2)) extended substantially perpendicularly with respect to the center part 5a. At this time, when the meat of the central part peripheral edge 5b moves to the outer body part 5c, the central part peripheral edge 5b is thinned and the body part 5c is thickened (in this example, the central part peripheral edge 5b is 4.4 mm). ± 0.5mm, body 5c is 7.6mm).

  If it progresses to step S3, the process extended to taper shape toward the trunk | drum 5c from the center part 5a of this workpiece | work 5 will be performed. Thereby, it inclines toward the center part periphery 5b from the center part 5a, and is shape | molded in the shape (refer FIG. 3 (S3)) extended along this inclination toward the trunk | drum 5c from the center part periphery 5b. .

  If it progresses to step S4, the process which crushes the whole workpiece | work 5 flatly in a plate | board thickness direction will be performed. Thereby, it shape | molds in the substantially planar shape (refer FIG. 3 (S4)) provided with the thinned center part 5a, the center part peripheral edge 5b, and the thickened trunk | drum 5c.

  Proceeding to step S5, torque converter cover 2 having thin portion 2a, thick portion 2b and end portion 2c as final shapes based on workpiece 5 formed in a substantially flat shape in step S4 (FIG. 3 (S5)). Molding).

(Details of molding process of torque converter cover 2)
Hereinafter, details of each step of FIG. 2 will be described.

(About Step S1)
FIG. 4 is a diagram illustrating a process according to step S1 of FIG. FIGS. 4A and 4B show before and after the process according to step S1, that is, before and after the operation of moving the dice 12 in the direction of the arrow in FIG.

  In step S1, as shown in FIG. 4A, the body portion 5c of the work 5 is held between the wrinkle retainer 11 and the die 12, and a substantially hemispherical punch 13 is disposed below the central portion 5a. To do.

  With such a configuration, the die 12 is moved in the direction of the arrow in FIG. As a result, the center part 5 a of the workpiece 5 is drawn by the punch 13 with overhanging. Thereby, as shown in FIG.4 (b), the center part 5a of the workpiece | work 5 is shape | molded by the simple curved shape which swelled upwards. At this time, the central portion 5a of the workpiece 5 is thinned.

(About step S2)
FIG. 5 is a diagram illustrating a process according to step S2 of FIG. FIGS. 5A and 5B respectively show before and after the process according to step S2, that is, before and after the operation of moving the dice 12 in the arrow direction of FIG.

  In step S <b> 2, as shown in FIG. 5A, the body portion 5 c of the work 5 is disposed on the upper surface of the wrinkle retainer 11, and the die 12 is disposed with a clearance T between the punch 13. At this time, the die 12 is arranged on the inner side (right side in FIG. 5) than at the time of step S1.

  With such a configuration, the die 12 is moved in the direction of the arrow in FIG. Then, as shown in FIG. 5B, ironing is performed between the die 12 and the punch 13 from the peripheral edge 5 b of the workpiece 5 toward the body portion 5 c. As a result, the peripheral edge 5b of the central portion of the workpiece 5 is reduced in thickness, and the reduced thickness portion moves toward the barrel portion 5c, and the barrel portion 5c of the workpiece 5 is increased in thickness. By adjusting the length of the clearance T, the thickness of the central peripheral edge 5b is reduced so as to be the same as the thickness of the central part 5a. In addition, as shown in FIG.5 (b), the center part periphery 5b of the workpiece | work 5 is shape | molded so that it may extend in a substantially perpendicular direction (substantially perpendicular to the center part 5a).

(About Step S3)
FIG. 6 is a diagram illustrating a process according to step S3 of FIG. FIGS. 6A and 6B show before and after the process according to step S3, that is, before and after the operation of moving the mold 14 in the direction of the arrow in FIG.

  In step S3, as shown in FIG. 6A, a mold 14 and a mold 15 are provided above and below the central portion 5a of the workpiece 5, respectively. Each of the mold 14 and the mold 15 includes substantially planar surface portions 14a and 15a. Molds 16 and 17 are disposed above and below the body portion 5c of the work 5, respectively. The mold 16 includes an inclined portion 16a that is inclined upward toward the outside (left side in FIG. 6). On the other hand, the mold 17 includes a substantially hemispherical projection 17a.

  With such a configuration, the mold 14 is moved in the direction of the arrow in FIG. Then, the workpiece 5 is first crushed in the plate thickness direction between the surface portion 14a and the surface portion 15a from the center portion 5a toward the center periphery 5b. Subsequently, the workpiece 5 is shaped so as to expand along the inclination of the inclined portion 16a between the inclined portion 16a and the protruding portion 17a from the central peripheral edge 5b toward the trunk portion 5c. Thereby, as shown in FIG.6 (b), the center part 5a of the workpiece | work 5 is shape | molded by substantially planar shape. Moreover, it shape | molds so that it may expand from the center part periphery 5b of the workpiece | work 5 to the trunk | drum 5c with the inclination-angle of the inclination part 16a. As a result, the workpiece 5 has a shape that expands in a tapered shape (conical shape) from the central portion 5a toward the body portion 5c.

(About step S4)
FIG. 7 is a diagram illustrating the process according to step S4 of FIG. FIGS. 7A and 7B respectively show before and after the process according to step S4, that is, before and after the operation of moving the mold 18 in the direction of the arrow in FIG.

  In step S4, as shown in FIG. 7A, dies 18 and 19 are disposed above and below the entire work 5, respectively. Each of the mold 18 and the mold 19 includes substantially planar surface portions 18a and 19b.

  With this configuration, the mold 18 is moved in the direction of the arrow in FIG. If it does so, the whole workpiece | work 5 will be crushed in the plate | board thickness direction between the surface part 18a and the surface part 19a. Thereby, as shown in FIG.7 (b), the whole workpiece | work 5 is shape | molded by substantially planar shape. Through the steps S1 to S4 described above, a substantially planar shape including the thinned central portion 5a, the central peripheral edge 5b, and the thickened barrel portion 5c can be obtained.

(About step S5)
FIG. 8 is a diagram illustrating a process according to step S5 of FIG. FIGS. 8A and 8B respectively show before and after the process according to step S5, that is, before and after the operation of moving the mold 20 in the direction of the arrow in FIG.

  In step S5, as shown to Fig.8 (a), the metal mold | dies 20 and 21 are each arrange | positioned above the whole workpiece | work 5 and the downward direction. Each of the mold 20 and the mold 21 has a concave portion 20a and a convex portion 21a according to the final shape to be molded based on the workpiece 5. Further, as shown in FIG. 8A, the mold 20 is configured to be thicker than the mold 21, and the clearance T <b> 2 is separated from the mold 21.

  With such a configuration, the mold 20 is moved in the direction of the arrow in FIG. If it does so, the whole workpiece | work 5 will be shape | molded so that it may become a final shape between the metal mold | die 20 and the metal mold | die 21 according to the recessed part 20a and the convex part 21a. In addition, the body 5c of the workpiece 5 is drawn at the position of the clearance T2. As a result, as shown in FIG. 8B, the torque converter cover 2 having a thin portion 2a, a thick portion 2b, and an end portion 2c as the final shape can be obtained.

  As described above, the details of each step in FIG. 2 have been described, but the steps relating to each step will be supplemented.

  It supplements about all the processes which concern on step S1 to S5. According to the workpiece forming method (or forming system) according to the present embodiment, all these steps are realized only by pressing without using processing that requires a large forming load such as coining. Therefore, a product having a wide range of thick portions and a wide range of thin portions can be formed easily and inexpensively. Moreover, the problem of the enlargement of mechanical equipment and the life of a mold can be prevented.

  Then, it supplements about the process which concerns on step S2. The process which concerns on step S2 is a process of thinning the center part periphery 5b of the workpiece | work 5. FIG. This step is preferable in that a wide range of thinning can be realized by expanding the thinned region to the central peripheral edge 5b in addition to the central portion 5a.

  Then, it supplements about the process which concerns on step S3. The process which concerns on step S3 is a process of shape | molding the workpiece | work 5 in the shape expanded in the taper shape (conical truncated cone shape) toward the trunk | drum 5c from the center part 5a. In this process, the central part 5a formed through the process related to the previous step S2 and the central part peripheral edge 5b extending substantially perpendicularly to the central part 5a are substantially straightened in the process related to the subsequent steps S4 and S5. In other words, it can be rephrased as a preparation process. If the process proceeds to step S4 or step S5 without going through the process related to step S3, the central part 5a and the central part peripheral edge 5b may be buckled. In particular, since the central part 5a and the central part peripheral edge 5b are thin, there is a higher risk of buckling than when the central part 5a is thick. However, it is preferable in that the risk of buckling can be prevented through the process according to step S3.

  Then, it supplements about the process which concerns on step S4. The process according to step S4 is a process of forming the entire work 5 into a substantially flat shape. In this process, it may be impossible to form a substantially flat shape due to restrictions on the forming load. Therefore, the process according to step S4 is not limited to being formed into a substantially flat shape, and may be formed into a shape corresponding to the final shape to be formed, similarly to the process according to step S5.

(Summary)
According to the workpiece forming method (or forming system) according to the present embodiment, the first step (S1) and the second step (S2) (first processing means (S1) and second processing means (S2). )), The central part 5a and the peripheral part 5b of the work 5 are reduced in thickness and the body part 5c of the work 5 is increased without using a coining process that requires a large molding load. And a product having a wide range of thin-walled parts can be molded inexpensively and easily. Further, in the third step (S3) and the fourth step (S3) (third processing means (S3) and fourth processing means (S4)), the center portion 5a and the center portion peripheral edge 5b of the workpiece 5 are separated. Since the gap is gradually expanded, it is possible to prevent the buckling from occurring at the central portion 5a and the peripheral portion 5b of the workpiece 5 (effects of the inventions according to claims 1 and 3).

  Further, according to the method for forming a workpiece according to the present embodiment, a wide-thick portion is formed in the fifth step (S5) by drawing the disk-shaped workpiece 5 in the first step (S1). Thus, the torque converter cover 2 having a wide range of thin portions can be formed inexpensively and easily (effect of the invention according to claim 2).

  As mentioned above, although embodiment of this invention was described, the said embodiment showed one of the application examples of this invention, and in the meaning which limits the technical scope of this invention to the specific structure of the said embodiment. Absent.

  In the above description, the case where the workpiece forming method according to the present invention is applied to the formation of the torque converter cover 2 has been described as an example. However, the present invention is not limited to this case. For example, you may apply to shaping | molding of a clutch drum.

It is a schematic sectional drawing of the cover for torque converters shape | molded with the shaping | molding method of the workpiece | work concerning this embodiment. It is a flowchart which shows the formation process of the cover for torque converters which concerns on this embodiment. Sectional drawing of the shape of the cover for torque converters concerning each process of Drawing 2 is shown. It is a figure explaining the process which concerns on step S1 of FIG. It is a figure explaining the process which concerns on step S2 of FIG. It is a figure explaining the process which concerns on step S3 of FIG. It is a figure explaining the process which concerns on step S4 of FIG. It is a figure explaining the process which concerns on step S5 of FIG.

DESCRIPTION OF SYMBOLS 1 Torque converter 2 Torque converter cover 2a Thin part 2b Thick part 2c End part 5 Work 5a Center part 5b Center part periphery 5c Body part step S1 (1st process, 1st processing means)
Step S2 (second step, second processing means)
Step S3 (third process, third processing means)
Step S4 (fourth process, fourth processing means)
Step S5 (fifth process, fifth processing means)

Claims (3)

A workpiece molding method for molding a final shape with a thickened end from a plate-shaped workpiece of a certain thickness,
A first step of reducing the thickness of the central portion by performing drawing using a substantially hemispherical punch at the central portion of the workpiece;
A second step of reducing the thickness of the peripheral portion of the central portion and increasing the thickness of the cylindrical portion by performing ironing from the peripheral portion of the central portion of the workpiece toward the outer cylindrical portion;
By crushing in the thickness direction from the center part of the workpiece to the periphery of the center part, the center part is formed into a substantially flat shape and is formed so as to expand from the periphery of the center part toward the body part at a substantially constant inclination angle. A third step;
A fourth step of forming the entire workpiece including the thinned central portion and the central portion peripheral edge and the thickened barrel portion into a substantially planar shape by crushing the entire workpiece in the thickness direction;
A fifth step of forming the final shape based on the workpiece formed into a substantially planar shape by the fourth step;
A method for forming a workpiece, comprising: The workpiece used in the first step is a disk having a constant thickness,
The method for forming a workpiece according to claim 1, wherein the final shape formed in the fifth step is a shape of a torque converter cover. A workpiece molding system for molding a final shape with a thickened end from a plate-shaped workpiece having a constant thickness,
A first processing means for reducing the thickness of the central portion by performing drawing using a substantially hemispherical punch at the central portion of the workpiece;
A second processing means for reducing the thickness of the peripheral portion of the central portion and increasing the thickness of the cylindrical portion by performing ironing from the peripheral portion of the central portion of the workpiece toward the outer cylindrical portion;
By crushing in the thickness direction from the central part of the workpiece to the peripheral edge of the central part, the central part is formed into a substantially flat shape and is formed so as to expand from the peripheral edge of the central part toward the body part at a substantially constant inclination angle. A third processing means;
A fourth processing means for forming the whole work including the thinned central part and the central part peripheral edge and the thickened body part into a substantially flat shape by crushing the whole work in the plate thickness direction;
A fifth processing means for forming the final shape based on the workpiece formed in a substantially planar shape by the fourth step;
A molding system comprising:

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