JP3667814B2 - Synchronizer ring manufacturing method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method of manufacturing a synchronizer ring used as a part of a synchromesh mechanism in a manual transmission of an automobile, and more particularly to a method of performing press processing as a basis.
[0002]
[Prior art]
As shown in FIGS. 9 and 10, this type of synchronizer ring (1) has a ring portion (1a) having a shape surrounding a cone, and an edge on the small diameter side of the ring portion (1a) in the axial direction. It has a plurality of claw portions (1b) protruding and provided at equal intervals in the circumferential direction.
[0003]
The synchronizer ring (1) is configured to synchronize rotation by frictionally engaging the conical surface of the ring portion (1a) with the conical surface of a gear having a different rotational speed in the synchromesh mechanism. In order to perform the synchronization smoothly, it is necessary to maintain the accuracy of the circularity of the ring portion (1a), the inclination angle accuracy of the conical surface, the position accuracy of the claw portion (1b), and the like.
[0004]
Conventionally, when the synchronizer ring (1) as described above is manufactured, a method based on cutting, a method based on press work, or the like has been employed.
[0005]
As a basic method of cutting, for example, a thick steel pipe is cut by cutting unnecessary portions into a predetermined shape by cutting, or a steel ring or the like is formed by roughing a ring product and then unnecessary. A method of scraping off a portion and processing it into a predetermined shape is employed. However, all of these methods are not preferable methods because they require a great amount of time for the cutting process, are inefficient, and cause an increase in cost.
[0006]
On the other hand, as a method based on the latter press work, conventionally, for example, the following method is employed.
[0007]
First, as shown in FIG. 5, blanking is performed on the steel plate to form a disk-shaped first intermediate processed product (P1).
[0008]
Subsequently, as shown in FIG. 6, the first intermediate processed product (P1) is drawn, and a truncated cone-shaped recess (2a) is provided at the center, and the outer peripheral edge of the recess (2a) is provided. A second intermediate processed product (P2) in which the flange portion (2c) is continuously provided is formed.
[0009]
Next, as shown in FIG. 7, in a mode in which the portion (3b) corresponding to the claw portion (1a) remains on the bottom wall of the recess (2a) of the second intermediate processed product (P2) 3rd intermediate processed product (P3) in which a plurality of claw portion forming pieces (3b) projecting in the inner diameter direction are formed on the small-diameter side edge of the ring portion (1a) having a conical circumference shape Form.
[0010]
Next, after squeezing the third intermediate processed product (P3), as shown in FIG. 8, the third intermediate processed product (P3) is subjected to burring (overhanging) processing, and the nail portion The forming piece (3b) is bent along the axial direction to form the claw portion (1b).
[0011]
Subsequently, as shown in FIG. 9, the large-diameter end of the ring portion (1a) is cut together with the flange portion (2c) by turning to form the synchronizer ring (1).
[0012]
Note that the thus processed synchronizer ring (1) is subjected to a surface hardening treatment, and a friction material is further bonded to produce a product.
[0013]
[Problems to be solved by the invention]
In the conventional manufacturing method described above, when the nail part forming piece (3b) of the third intermediate processed product (P3) is bent along the axial direction, a crack is generated in the base part of the nail part forming piece (3b). In order to prevent this, the claw portion forming piece (3b) is bent after the third intermediate processed product (P3) is softened by the sinter process.
[0014]
However, since the tempering process, which is a technology different from the press technology, is inserted between the press work such as punching and the press work such as burring, the process can be smoothly transferred before and after the tempering process. However, there is a problem that the production efficiency is lowered and the cost is increased.
[0015]
Further, when the internal stress is released by the tempering process, there is a problem that the intermediate processed product (P3) is deformed, the accuracy of the perfect circle is lowered, and the defective product occurrence rate is increased.
[0016]
In addition, even if the claw-forming pieces (3b) are formed with high accuracy in the drilling process, not all claw-forming pieces (3b) may be bent in a balanced manner during burring, and the claw position accuracy is reduced. From this point as well, there was a problem that the incidence of defective products was high.
[0017]
On the other hand, in the step of obtaining the third intermediate processed product (P3) by drilling, for example, as shown in FIG. 11, both the base portions of the claw portion forming piece (3b) are punched to remove the stealing notch portion (3d). If it is formed, it is possible to prevent cracks from occurring when the nail is bent without performing a sinter treatment. However, when the stealing cutout portion (3d) is formed, the strength of the claw portion (1b) is reduced, which causes a new problem that a high-quality product cannot be manufactured.
[0018]
This invention solves the above-mentioned problems of the prior art, maintains high production efficiency, reduces production costs, and further reduces the occurrence rate of defective products, while keeping the circularity accuracy of the conical surface, inclination angle accuracy, claw position An object of the present invention is to provide a method of manufacturing a synchronizer ring that can manufacture a high-quality synchronizer ring that is excellent in accuracy and has no cracks.
[0019]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a method for manufacturing a synchronizer ring in which a plurality of claw portions protruding in the axial direction are provided at equal intervals in the circumferential direction on the small-diameter side edge of a conical circumferential ring portion. A step of punching a metal plate to obtain a disk-shaped first intermediate processed product, and drawing the first intermediate processed product to obtain a second intermediate processed product having a truncated conical recess. A step of obtaining a conical circumferential shape by performing a drilling process in a manner in which a portion corresponding to the plurality of claw portions and an outer punching margin thereof remain on the bottom wall of the concave portion of the second intermediate processed product A step of obtaining a third intermediate workpiece in which a plurality of punching allowance claw-forming pieces protruding in the inner diameter direction are provided at equal intervals in the circumferential direction at the small-diameter side edge of the ring portion; A plurality of punching claw portions are formed by burring processing Are bent along the axial direction to obtain a fourth intermediate work product, and a plurality of punching allowance claw portion forming pieces of the fourth intermediate work product are subjected to a total die cutting process to obtain a punching allowance. And a step of cutting a large diameter side end portion of the intermediate processed product together with a flange portion provided on a peripheral edge thereof by turning, and a summary thereof. .
[0020]
Furthermore, in the present invention, it is preferable to set the width of the punching allowance to 1 to 2 times the thickness of the intermediate processed product.
[0021]
[Action]
In the method of manufacturing a synchronizer ring according to the present invention, a punching allowance claw portion forming piece is formed by drilling, the forming piece is bent along the axial direction by burring, and then the punching allowance is excised. Therefore, even when a crack is generated in the punching allowance when the nail is bent by the burring process, the crack does not reach the nail. Therefore, no cracks remain in the product by cutting the punching allowance in the subsequent process. Furthermore, cracks can be prevented from occurring without performing the tempering treatment, so there is no adverse effect caused by the tempering treatment.
[0022]
Moreover, since each process implemented by this invention utilizes the technique of the same quality, such as press work and cutting, it can transfer to each process smoothly from each process. In the present invention, the nail position accuracy corresponds to the die accuracy used in the total die cutting after the burring process, so that the nail portion is formed with high position accuracy without being adversely affected by the burring process. it can. Further, in the present invention, since the punching allowances of the plurality of punching allowance claw portion forming pieces are all excised at the same time, the balance is maintained over the entire circumference at the time of excision, and the roundness accuracy of the conical surface is increased. A decrease in tilt accuracy can be effectively prevented.
[0023]
In the present invention, when the width of the punching allowance is set to 1 to 2 times the plate thickness of the intermediate processed product, the occurrence of cracks can be prevented more reliably.
[0024]
【Example】
Hereinafter, a method for manufacturing a synchronizer ring according to an embodiment of the present invention will be described in detail, but the same parts as those in the conventional example will be described using the same reference numerals.
[0025]
First, blanking processing is performed on a steel plate (cold rolled steel plate) to form a disk-shaped first intermediate processed product (P1) (see FIG. 5).
[0026]
Subsequently, the first intermediate processed product (P1) is drawn, and a substantially frustoconical concave portion (2a) is provided at the center, and a flange portion (2c) is provided at the outer peripheral edge of the concave portion (2a). A second intermediate processed product (P2) provided continuously is formed (see FIG. 6).
[0027]
Next, as shown in FIGS. 1 and 2, a portion (21) corresponding to the claw portion of the synchronizer ring and a punching allowance (22) outside thereof are formed on the bottom wall of the recess of the second intermediate processed product (P2). The inner diameter is removed (drilled) in such a manner as to remain. Thus, a ring portion (1a) having a substantially conical circumferential shape, and a plurality of punching allowance claws provided on the small diameter side edge of the ring portion (1a) in the inner diameter direction and provided at equal intervals in the circumferential direction A third intermediate processed product (P13) having the part forming piece (20) is formed.
[0028]
Here, the width (W) of the punching allowance (22) in the third intermediate processed product (P13) has a lower limit of 0.5 times or more and an upper limit of 3 with respect to the plate thickness of the intermediate processed product (P13, etc.). It is preferable to set it to be twice or less, and it is even more preferable to set the addition / subtraction value to 1.0 times or more and the upper limit value to 2 times or less. That is, when the punching allowance claw part forming piece (20) is bent as will be described later, a crack may occur at the base portion, but at this time, if the punching allowance width (W) is too small, The crack reaches the nail part corresponding part (21), and the possibility that the crack remains in the product and becomes a defective product increases, which is not preferable. On the other hand, if the punching allowance width (W) is too large, the bending strength of the punching allowance claw portion forming piece (20) increases, and the possibility that the bending process cannot be performed smoothly increases, which is not preferable.
[0029]
In FIG. 1 and FIG. 2, for the purpose of facilitating the understanding of the invention, the boundary between the nail portion corresponding portion (21) and the punching allowance (22) of the punching allowance nail portion forming piece (20) is indicated by an imaginary line. Although shown, it goes without saying that this boundary line is not actually displayed (the same applies to FIG. 3).
[0030]
After the drilling step is completed, as shown in FIG. 3, the third intermediate processed product (P13) is subjected to burring (overhanging) processing, and the plurality of punching substitution claw portion forming pieces (20) are formed. At the same time as bending along the axial direction, the ring portion (1a) is formed into a predetermined conical circumferential shape to form a fourth intermediate workpiece (P14).
[0031]
At the time of this nail bending, a crack may occur at the base portion of the punching allowance claw portion forming piece (20), but the crack enters only the punching allowance (22) and reaches the nail portion corresponding portion (21). There is no such thing as reaching.
[0032]
Subsequently, as shown in FIG. 4, a total punching (total cutting) process is simultaneously performed on the plurality of punching allowance claw forming pieces (20) of the fourth intermediate processed product (P14), and each punching allowance is performed. (22) is excised at a time to form the nail portion (1b). At this time, since the punching allowance (22) having a crack is cut off, no crack remains in the claw portion (1b).
[0033]
Next, the edge part on the large diameter side of the ring part (1a) is cut together with the flange part (2c) by edge turning to form the synchronizer ring (1).
[0034]
In addition, the synchronizer ring (1) processed in this way is subjected to a surface hardening process as in the conventional case, and a friction material is further bonded to produce a product.
[0035]
According to the ring manufacturing method of the present embodiment, the punching allowance claw portion forming piece (20) formed by drilling is bent by burring, and then the punching allowance (22) is cut by total die cutting. Therefore, even when the nail is bent, there is a crack in the punching allowance (22), but the crack does not reach the nail corresponding part (21). Therefore, the high quality synchronizer ring (1) without a crack can be reliably manufactured by excising the punching allowance (22) in the subsequent process. Furthermore, since it is not necessary to subject the intermediate processed product to a tempering treatment, it is possible to prevent adverse effects caused by the tempering treatment, for example, a reduction in roundness accuracy, etc., and a defective product occurrence rate can be kept low.
[0036]
Further, in this embodiment, since the same quality techniques such as press working and cutting work are produced in series, for example, it is not necessary to perform a different technique (sintering process) in an intermediate process as in the prior art. Processes can be transferred smoothly, and production efficiency can be improved and costs can be reduced. In addition, since continuous technologies are connected, a continuous processing method such as transfer processing can also be adopted, and the production efficiency can be further improved and the cost can be reduced.
[0037]
In the present embodiment, since the ring portion (1a) is formed into a predetermined shape by burring, even higher roundness accuracy can be obtained.
[0038]
Further, in this embodiment, the claw position accuracy (claw pitch accuracy) corresponds to the mold accuracy used in the total die cutting after burring, and thus is not adversely affected by the burring and has a high position. The claw portion (1b) can be formed with accuracy.
[0039]
In addition, since the punching allowance (22) of the punching allowance claw forming piece (20) is all excised at the same time, the balance is maintained over the entire circumference at the time of excision, and the roundness accuracy and inclination accuracy of the conical surface are maintained. Can be effectively prevented, and in this respect as well, the defective product generation rate can be kept low.
[0040]
In the present invention, the number of claws of the manufactured synchronizer ring (1) is not limited.
[0041]
【The invention's effect】
As described above, according to the method of manufacturing a synchronizer ring of the present invention, after forming a punching substitution claw portion forming piece by drilling, and bending the formed piece along the axial direction by burring, Since the nail portion is formed by cutting away the punching allowance, even when a crack occurs in the punching allowance when the nail is bent by the burring process, the crack does not reach the nail corresponding portion. Therefore, a high-quality synchronizer ring without a crack in the nail portion can be reliably manufactured by excision of the punching allowance in the subsequent process. Further, since the squeezing process does not have to be performed, adverse effects caused by the squeezing process, for example, a decrease in roundness accuracy can be prevented, and the defective product generation rate can be kept low. In addition, since each process performed in the present invention uses the same quality technology such as pressing and cutting, the transition from each process to the next process can be smoothly performed, so that the production efficiency is improved and Cost can be reduced. Further, in the present invention, the nail position accuracy corresponds to the mold accuracy used in the total die cutting after the nail bending process, so that the nail portion is not adversely affected by the burring process and the nail portion is highly accurate. It is possible to form a high quality ring product. Further, in the present invention, since the punching allowances of the plurality of punching allowance claw portion forming pieces are all excised at the same time, the balance is maintained over the entire circumference at the time of excision, and the roundness accuracy of the conical surface is increased. It is possible to effectively prevent the tilt accuracy from being lowered, and to obtain an effect of further reducing the defective product occurrence rate.
[0042]
In the present invention, when the width of the punching allowance is set to 1 to 2 times the plate thickness of the intermediate processed product, there is an advantage that cracks can be prevented more reliably while ensuring high production efficiency.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an intermediate processed product immediately after drilling in a ring manufacturing method according to an embodiment of the present invention.
FIG. 2 is a plan view showing the periphery of a punching allowance claw portion forming piece of an intermediate processed product that has been drilled by the ring manufacturing method of the embodiment.
FIG. 3 is a perspective view showing an intermediate product immediately after claw bending in the ring manufacturing method of the embodiment.
FIG. 4 is a perspective view showing an intermediate processed product in a punching allowance and a flange cutting process in the ring manufacturing method of the embodiment.
FIG. 5 is a perspective view showing an intermediate processed product immediately after punching in a conventional ring manufacturing method.
FIG. 6 is a perspective view showing an intermediate processed product immediately after drawing in the conventional method.
FIG. 7 is a perspective view showing an intermediate processed product immediately after drilling in the conventional method.
FIG. 8 is a perspective view showing an intermediate processed product immediately after bending a nail in a conventional method.
FIG. 9 is a perspective view showing an intermediate processed product immediately after flange cutting in a conventional method.
FIG. 10 is a side sectional view showing a synchronizer ring.
FIG. 11 is a plan view showing the periphery of a nail part forming piece of an intermediate processed product immediately after drilling in a conventionally studied manufacturing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Synchronizer ring 1a ... Ring part 1b ... Claw part 2a ... Recessed part 2c ... Flange part 20 ... Punching substitution claw part formation piece 21 ... Claw part corresponding part 22 ... Punching allowances P1, P2, P13, P14 ... Intermediate processed goods W ... Punch width

Claims (2)

A method for manufacturing a synchronizer ring in which a plurality of claw portions protruding in the axial direction are provided at equal intervals in the circumferential direction on the small-diameter side edge of the ring portion having a conical circumference shape,
Punching a metal plate to obtain a disc-shaped first intermediate processed product;
Drawing the first intermediate workpiece to obtain a second intermediate workpiece having a truncated cone-shaped recess;
Drilling is performed on the bottom wall of the concave portion of the second intermediate processed product so that the portions corresponding to the plurality of claw portions and the punching allowances outside thereof remain, so that the ring portion having a conical circumferential shape is formed. A step of obtaining a third intermediate processed product in which a plurality of punching allowance claw portion forming pieces protruding in the inner diameter direction are provided at equal intervals in the circumferential direction on the small diameter side edge;
Performing a burring process on the third intermediate processed product and bending the plurality of punching allowance claw forming pieces along the axial direction to obtain a fourth intermediate processed product;
A step of forming a nail part by performing total die cutting for a plurality of punching allowance claw part forming pieces of the fourth intermediate processed product, and simultaneously cutting out the punching allowance;
Cutting the large-diameter side end of the intermediate workpiece together with the flange provided on the periphery thereof by turning, and a method of manufacturing a synchronizer ring. The method of manufacturing a synchronizer ring according to claim 1, wherein a width of the punching allowance is set to 1 to 2 times the thickness of the intermediate processed product.

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