JP2017154152A - Wheel rim and method for manufacturing same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to manufacture a wheel rim from a metal plate (tabular blank) without use of weldment.SOLUTION: A method for manufacturing a wheel rim comprises: a first punching process 10 in which a blank is obtained from a metal plate by contour punching; a drawing process 20 in which a bowl-shaped blank, which comprises a flange at one end and a bottom at the other end thereof, is obtained from the blank; a second punching process 30 in which the bottom is formed into a hollow bottom by piercing; a flange molding process 40 in which the flange is molded, whereby a hollow bowl-shaped blank is obtained; a rising process 50 which rises the hollow bottom in an axial direction thereby obtaining an intermediate molding; a flaring process 60 which pushes at least one end of the intermediate molding; and a main molding process 70 in which a wheel rim is obtained from the intermediate molding of which both ends are pushed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wheel rim and a manufacturing method thereof.

  Conventionally, as a method of manufacturing a wheel rim, a method of manufacturing a rim by roll forming using a cylindrical material manufactured by upset welding is generally used (see Patent Documents 1 to 4). A method of manufacturing a wheel in which a rim and a disk are integrated using a plate-like material is also known (see Patent Document 5).

JP 2003-275837 A JP 2005-52884 A JP 2013-52442 A JP2015-110232A JP 2011-240360 A

  In the methods described in Patent Documents 1 to 4, it is necessary to manufacture a cylindrical material from a plate material by welding. However, the manufacturing of this cylindrical material requires enormous capital investment and its maintenance cost, which increases the manufacturing cost. Moreover, when a welding defect arises, it will have a bad influence on the performance as a wheel.

  In the method described in Patent Document 5, since a wheel in which a rim and a disk are integrated is manufactured, there are restrictions on the shapes of the rim and the disk.

  Therefore, one of the objects of the present invention is to provide a method for manufacturing a wheel rim without using a cylindrical material manufactured by upset welding from a metal plate (plate-shaped material).

  A normal wheel rim has no difference in thickness between the left and right flanges. However, if a predetermined plate thickness difference is provided in the left and right flanges, the mass balance on the left and right sides of the wheel can be controlled by adjusting the mounting position of the disc and by adjusting the mounting position of the brake and other asymmetrical peripheral parts. Is possible. As a result, running stability superior to that of a normal wheel can be imparted. Such an improvement in performance becomes remarkable particularly in the case of a wheel rim for a motorcycle.

  Accordingly, another object of the present invention is to provide a wheel rim that can be used for a wheel having excellent running stability and that has a difference in plate thickness between the left and right flange portions.

[A] A method of manufacturing a wheel rim from a metal plate,
(1) A first punching step of obtaining a blank from the metal plate by outer shape punching;
(2) A drawing step of obtaining a bowl-shaped material having a preliminary flange at one end and a bottom at the other end from the blank;
(3) a second punching step in which the bottom is a hollow bottom by punching;
(4) A flange forming step of forming the preliminary flange into a flange shape;
(5) A rising step in which the hollow bottom is raised in the axial direction to obtain an intermediate molded body;
(6) a flaring step of spreading at least one end of the intermediate molded body;
(7) A wheel rim manufacturing method comprising: a main molding step of obtaining a wheel rim from an intermediate molded body having both ends spread.

  [B] The method for manufacturing a wheel rim according to [A], wherein in the step (1), a hole blanking process is further performed to obtain a hollow blank.

  [C] The method for manufacturing a wheel rim according to [A] or [B], wherein in the step (3), an outer shape is further cut to change the shape of the preliminary flange.

  [D] The wheel rim manufacturing method according to any one of the above [A] to [C], further comprising a roll processing step and / or a sizing step after the main forming step.

[E] A wheel rim having flanges at both ends, a bead seat inside thereof, and a well inside thereof, and when the thickness at the center line of the rim is T ₀ , the thickness T _FA of one flange is 0 .50T ₀ or 1.00T less than _0, the thickness T _FB of the other flange is 1.50T ₀ less than the 1.00T _0, the wheel rim.

  [F] The wheel rim of [E] above, wherein the wheel rim is made of an iron alloy plate.

  According to the manufacturing method of the present invention, it is possible to provide a method for manufacturing a wheel rim without using a cylindrical material manufactured by upset welding from a metal plate (plate-shaped material). Moreover, according to the wheel rim of this invention, it is providing the wheel rim with the plate | board thickness difference of a right-and-left flange part which can be used for the wheel excellent in driving | running | working stability.

The flowchart explaining one Embodiment of the manufacturing method of this invention The figure which shows the example of a 1st punching process. (a) shows an example of the apparatus configuration, and (b) shows an example of a blank manufactured by this process. The figure which shows the example of an aperture_diaphragm | restriction process. (a) shows an example of an apparatus configuration, and (b) shows an example of a bowl-shaped material manufactured by this process. The figure which shows the other example of an aperture_diaphragm | restriction process. (a) shows an example of an apparatus configuration, and (b) shows an example of a bowl-shaped material manufactured by this process. The figure which shows the example of a 2nd punching process. (a) shows an example of an apparatus configuration, and (b) shows an example of a hollow bowl-shaped material manufactured by this process. The figure which shows the example of a flange shaping | molding process. (a) shows an example of an apparatus configuration, and (b) shows an example of a hollow bowl-shaped material manufactured by this process. The figure which shows the example of a starting process. (a) shows an example of an apparatus configuration, and (b) shows an example of an intermediate molded body manufactured by this process. The figure which shows the example of a flaring process. (a) shows an example of an apparatus configuration, and (b) shows an example of an intermediate molded body manufactured by this process. The figure which shows the example of this shaping | molding process. (a) shows an example of an apparatus configuration, and (b) shows an example of a wheel rim manufactured by this process. The figure which shows the example of the wheel rim | limb of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1. Wheel Rim Manufacturing Method As shown in FIG. 1, the wheel rim manufacturing method according to the present embodiment includes a first punching step 10 in which a blank is obtained from the metal plate by an outline punching process, and one end from the blank. A drawing process 20 for obtaining a flange-shaped material (bottomed cylindrical material) having a bottom at the other end of the preliminary flange, and a second punching process 30 for obtaining a hollow bowl-shaped material using the bottom as a hollow bottom by punching. A flange forming step 40 for forming the preliminary flange into a flange shape, a start-up step 50 for raising the hollow bottom portion in the axial direction to obtain an intermediate formed body, and a flare for spreading at least one end of the intermediate formed body A ring process 60 and a main molding process 70 for obtaining a wheel rim from the intermediate molded body whose both ends are expanded.

  As shown in FIG. 2, in the first punching step 10, for example, the metal plate 1 (substantially square) is subjected to outer shape punching by the upper mold 10 a and the lower mold 10 b to obtain a blank 2 (substantially circular). . In the first punching step 10, the above-described outer shape punching process is performed after the central portion of the metal plate 1 has been punched in advance, or the central portion of the metal plate 1 is punched simultaneously with the outer shape punching process. The hollow blank may be obtained by punching the central portion of the metal plate 1 after performing the above-described outer shape punching process. In addition, the diameter of the hole formed in this hollow blank is a thing smaller than the magnitude | size of the hole formed by a subsequent punching process. When such a hollow blank is used, the processing load when the hole is expanded can be reduced, the reduction in thinning during processing can be suppressed, and the mass balance of the left and right flanges of the final product can be easily adjusted.

  As the metal plate, various plate materials such as an iron alloy plate and an aluminum alloy plate can be used. In particular, an iron alloy plate is preferably used.

  As shown in FIG. 3, in the drawing step 20, the blank 2 is drawn by an upper mold 20a and a lower mold 20b, and a bowl-shaped material 3 having a preliminary flange 3a at one end and a bottom 3b at the other end is obtained. can get. The drawing step 20 may be to obtain the bowl-shaped material 3 having a predetermined shape by a single process, or to obtain the bowl-shaped material 3 having a predetermined shape by two or more processes. That is, as shown in FIG. 4, in the drawing step 20, the bowl-shaped material 3 is drawn by the upper mold 21 a and the lower mold 21 b, and the spare flange 3 a is at one end and the bottom 3 b is at the other end. And a step of obtaining a bowl-shaped material 3A having a preliminary shape corresponding to a bead sheet or the like of the final product.

  As shown in FIG. 5, in the second punching step 30, the bowl-shaped material 3 </ b> A is punched by the upper mold 30 a and the lower mold 30 b to obtain a hollow bottom 3 </ b> B having a hole 3 c in the bottom 3 b. . In addition, in this figure, although the example which processes the bowl-shaped raw material 3A provided with a preliminary | backup shape is demonstrated, you may punch a hole-shaped material 3 shown in FIG. In the second punching process 30, the shape of the spare flange 3a is changed in advance by outline punching, and then the punching process is performed, or the shape of the spare flange 3a is changed by outline punching simultaneously with the punching process, It may be a step of changing the shape of the preliminary flange 3a by the outer shape punching after the processing. As described above, in the second punching process, if the configuration is such that the outer shape is punched and the shape of the preliminary flange is changed, the variation in the flange width due to the material anisotropy can be minimized. There is.

  As shown in FIG. 6, in the flange forming step 40, the preliminary flange 3a of the bowl-shaped material 3b is molded into a predetermined flange shape, and then, as shown in FIG. 7, the hollow bottom 3b is the shaft of the bowl-shaped material 3C. The intermediate molded body 3D is obtained in the direction (in the direction of the arrow in the figure). In the present embodiment, the case where the hollow bottom portion 3b is raised after forming the preliminary flange 3a into a flange shape has been described. Alternatively, the preliminary flange 3a may be formed into a flange shape after the hollow bottom 3b is raised.

  As shown in FIG. 8, the flaring process 60 is a process of expanding at least one end of the intermediate molded body 3D. In addition, as in the example shown in FIG. 8, the end portion (flange side end portion) that is 3a in the flange shape of the bowl-shaped material 3 is processed into a final product shape or a shape close to the final product by drawing. When processing the intermediate formed body 3D, it is only necessary to push and spread only the end portion (bottom side end portion) where the bottom portion 3b of the bowl-shaped material 3 was present. On the other hand, when the flange end is not processed to the final product shape or the shape close to the final product, it is necessary to spread both ends (both the flange side end and the bottom end) of the intermediate molded body 3D. is there.

  As shown in FIG. 9, in the main molding step 70, the intermediate molded body 3E that has been spread out is a wheel that includes a flange 4a, a bead sheet 4b, and a well 4c having a predetermined shape by an upper mold 70a and a lower mold 70b. A rim 4 is obtained. At this time, for example, when the upper mold 70a is lowered using the cam mechanism, the plurality of outer molds 70c move from the outside to the inside of the intermediate molded body 3E, thereby pressing the intermediate molded body 3E. A wheel rim having a predetermined shape can be obtained. Although illustration is omitted, it is more preferable that after this step, a roll processing step and / or a sizing step is further performed to adjust the shapes of the flange 4a, the bead sheet 4b, the well 4c, and the like.

2. Wheel Rim As shown in FIG. 10, the wheel rim 4 of the present embodiment is a wheel rim having flanges 4a at both ends, a bead seat 4b inside thereof, and a well 4c inside thereof, and a difference in plate thickness between the left and right flanges. It is characterized by providing. By providing such a plate thickness difference, it is possible to control the mass balance on the left and right sides of the wheel by adjusting the mounting position of the disk and adjusting the mounting position of the brake and other peripheral parts that are asymmetrical to the left and right. As a result, running stability superior to that of a normal wheel can be imparted. However, if the above plate thickness difference is too large, processing cracks occur.

Therefore, when the thickness at the rim center line is T ₀ , the thickness T _FA of one flange is 0.50 T ₀ or more and less than 1.00 T ₀ , and the thickness T _FB of the other flange is 1. 00T is required to be more than ₀ 1.50T ₀ below. The lower limit of the thickness T _FA of one of the flanges is preferably 0.60 T _0, the upper limit is preferably 0.90T _0. The lower limit of the thickness T _FB of the other flange is preferably 1.10 T ₀ , and the upper limit is preferably 1.40 T ₀ .

  The wheel rim according to the present embodiment is particularly useful as a wheel rim for a motorcycle. In a two-wheeled vehicle, the mass balance of the vehicle body is often not equal to the left and right, and in such a case, it is possible to improve the mass balance of the entire vehicle body with the wheel rim of the present invention. The wheel rim according to the present embodiment is preferably made of an iron alloy plate.

  According to the manufacturing method of the present invention, it is possible to provide a method for manufacturing a wheel rim without using welding from a metal plate (plate-shaped material). Moreover, according to the wheel rim of this invention, it is providing the wheel rim with the plate | board thickness difference of a right-and-left flange part which can be used for the wheel excellent in driving | running | working stability.

1 metal plate 2 blank 3 bowl-shaped material 3A after drawing process bowl-shaped material after drawing process (with preliminary shape)
3B Hollow bowl-shaped material after second punching process 3C Hollow bowl-shaped material after flange molding process (flange molding)
Intermediate molded body after 3D start-up process (bottom of bottom)
3E Intermediate molded body 3a after flaring process Preliminary flange 3b Bottom 3c Hole 4 Wheel rim 4a Flange 4b Bead sheet 4c Well 10 First punching process 10a Upper mold 10b in the first punching process Lower mold 20 in the first punching process Drawing process 20a Upper mold 20b of drawing process Lower mold 21a of drawing process Upper mold (with preliminary shape)
21b Lower die of drawing process (with preliminary shape)
30 Second punching process 30a Upper die 30b of the second punching process Lower mold 40 of the second punching process Flange forming process 40a Upper mold 40b of the flange forming process Lower mold 50 of the flange forming process Start-up process 50a Start-up Upper mold 50b in the process Lower mold 60 in the startup process Flaring process 60a Upper mold 60b in the flaring process Lower mold 70 in the flaring process Main molding process 70a Upper mold 70b in the main molding process Lower mold 70c Outer mold of main molding process

Claims (6)

A method of manufacturing a wheel rim from a metal plate,
(1) A first punching step of obtaining a blank from the metal plate by outer shape punching;
(2) A drawing step of obtaining a bowl-shaped material having a preliminary flange at one end and a bottom at the other end from the blank;
(3) a second punching step in which the bottom is a hollow bottom by punching;
(4) A flange forming step of forming the preliminary flange into a flange shape;
(5) A rising step in which the hollow bottom is raised in the axial direction to obtain an intermediate molded body;
(6) a flaring step of spreading at least one end of the intermediate molded body;
(7) A wheel rim manufacturing method comprising: a main molding step of obtaining a wheel rim from an intermediate molded body having both ends spread.   The wheel rim manufacturing method according to claim 1, wherein in the step (1), a hole blanking process is further performed to obtain a hollow blank.   The wheel rim manufacturing method according to claim 1 or 2, wherein in the step (3), an outer shape is further cut to change the shape of the flange. A roll processing step and / or a sizing step are further provided after the main forming step.
The method for manufacturing a wheel rim according to any one of claims 1 to 3. A wheel rim having flanges at both ends, a bead seat inside, and a well inside.
When the thickness at the rim center line is T ₀ , the thickness T _FA of one flange is 0.50 T ₀ or more and less than 1.00 T ₀ , and the thickness T _FB of the other flange is 1.00 T _0. Wheel rim that is more than 1.50T _{0 and} less.   The wheel rim according to claim 5, wherein the wheel rim is made of an iron alloy plate.

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