JPH06246382A - Method for forming rim part of automobile wheel - Google Patents

Abstract

PURPOSE:To improve a formability of a rim and together to improve an efficiency of production in a method for producing a rim part of an automobile wheel with the combination of a cutting and a roll-forming of a rim corresponding part of a raw material to be machined capable of being plastically worked. CONSTITUTION:A raw material to be machined 10 is constituted by integrally forming a disk part 1 and a rim corresponding part raised in an annular state on an outer circumference of an attaching flange part arranged continuously to the disk part 1, an inner circumferential area of the rim corresponding part 12 of the raw material to be machined 10 is clamped and held between a pair of 1st and 2nd dies 3a, 3b, and a forming roller 4 is arranged on the outer periphery of the boundary of these dies 3a, 3b in relatively rotatable to them and is supported in movable parallel to and in a direction inward orthogonal to an axial line of the 1st and the 2nd dies 3a, 3b. The cross section of outer rim 2a is formed by forcible pressing a max. diameter part 41 of this forming roller 4 inside the rim corresponding 12 through a prescribed route and finally opposing an outer rim forming part 4a to a 1st annular die part 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a rim portion of an automobile wheel integrally formed from a material having a high plastic workability such as an aluminum alloy or a magnesium alloy, and in particular, after decomposing a required portion of the material, The present invention relates to a rim portion forming method of finishing a rim section.

[0002]

2. Description of the Related Art The rim portion of an automobile wheel is integrally connected to the periphery of the disc portion of the wheel or the periphery of an annular mounting flange for mounting the disc portion. A wheel of a type in which a rim portion is continuously provided on the periphery of the disc portion, and a method of forming a rim portion whose rim cross section is symmetrical with respect to the disc portion is disclosed in Japanese Patent Publication No. 57-554.
Disclosed in 98.

In this method, as shown in FIGS. 1 to 3, a semi-finished product in which the parts other than the rim part are finished to a final shape is manufactured in advance, and a rim corresponding part (1
After cleaving 2) into an inner rim corresponding part and an outer rim corresponding part as shown in FIG. 2, this cleaved part is finished into a rim cross section by a forming roller as shown in FIG. In this case, since the shape of the outer peripheral surface of the forming roller is adapted to that of the rim outer peripheral surface, the entire rim cross section can be formed at a time by roll forming using the forming roller, and the work of the work of the rim cross section can be performed. The sex can be improved.

However, this conventional method is difficult to use as it is for molding a rim portion of an automobile wheel in which the disc portion (drop center portion) is biased to one side of the rim cross section. When the conventional method is adopted, the rim-corresponding portion (12) is cleaved at the outer peripheral portion of the disk portion, but the width of the inner rim portion and the width of the outer rim portion of the automobile wheel are largely different. Therefore, when the inner rim-corresponding part and the outer rim-corresponding part, which are formed by cleaving, are roll-formed and finished into the final cross-sectional shape, the degree of spread of each part is greatly different.

That is, even if spreading is performed only by the above-mentioned forming roller after dehiscence, the flow of the material toward the inner rim end edge direction in the inner rim-corresponding portion becomes slow, and this processing requires a long time, This is because the processing up to the final cross section becomes insufficient even if the pressure of the pressure roller is increased.

[0006]

[Technical Problem] The present invention has been made in view of the above-mentioned point, and "A rim-corresponding portion (12) of a workable material (10) capable of being plastically processed is combined with a combination of cleaving and roll forming.
In the method of molding on the rim part of an automobile wheel ”,
It is a technical subject to improve the moldability of a rim and to improve its manufacturing efficiency.

[0007]

[Technical Means] The present invention was devised in order to solve the above technical problem, "The material to be processed (10) is a disk portion (1) on the inner circumference of a rim-corresponding portion (12) which is raised in an annular shape, or , The mounting flange portion is integrally formed, and the inner peripheral region of the rim equivalent portion (12) of the workpiece material (10) is paired with the first and second molds (3a) (3b).
A molding roller (4), which is held by pinching and is held by the outer periphery of the boundaries of these molds and which is supported so as to rotate relative to them and to be movable toward the boundaries, is arranged in the first mold (3a). A first annular mold part (32) adapted to the cross section of the outer rim (2a) is formed on the outer peripheral body part on the end face side, and the forming roller (4) is formed from one of the maximum diameter parts (41) to The outer rim molded portion (4a) up to the end, and the outer peripheral surface of this outer rim molded portion (4a) matches the shape from a part of the drop center to the outer rim (2a) end,
By pushing the maximum diameter part (41) of the forming roller (4) into the rim-corresponding part (12) along a predetermined path so that the outer rim forming part (4a) finally faces the first annular mold part (32). , The outer rim (2a) is molded in cross section ”.

[0008]

The above technical means of the present invention operates as follows. The material other than the rim-corresponding portion (12) is finished into a final shape by the forging process, and the processed material (10) is subjected to the molding method of the present invention. At least the portion corresponding to the outer rim of (12) is formed into the final rim shape.

In this molding method, the material to be processed is
The disk part (1) of (10) is held by being pressed between the first and second molds (3a) and (3b). In this state, the first and second
The molds (3a) (3b) and the forming roller (4) are rotated relative to each other, and the forming roller (4) is moved along a predetermined moving path to the first and second
Push it to the mold (3a) (3b) side and finally the outer rim molding part (4a)
Are opposed to the first annular mold part (32).

At this time, the maximum diameter portion of the forming roller (4)
Since (41) is the most projecting portion on the outer peripheral surface, when the molding roller (4) is pushed into the rim-corresponding portion (12) side, first, the maximum diameter portion (41) is moved to the rim-corresponding portion (41). When a predetermined position of 12) is cleaved and further the cleaving proceeds, at least the outer rim equivalent part of the cleaved part is spread by the outer rim forming part (4a) of the forming roller (4). At the same time, the outer rim equivalent portion is spread to a corresponding rim cross section, and finally, this outer rim corresponding portion is a shape sandwiched between the outer rim molding portion (4a) and the first annular mold portion (32), that is, the outer rim (2a ) Is finished.

Thereafter, the cross section of the inner rim side is the above-mentioned forming roller.
Finished by spinning roll processing other than (4) and other roll forming processing. In addition, the range from the outer rim (2a) to a part on the inner rim side of the drop center is formed by the forming roller (4).
May be finished at the same time. To this end, this forming roller (4) is, for example, the outer rim forming part (4a).
Then, an inner rim molding portion corresponding to a part of the drop center on the inner rim side is provided.

[0012]

[Effects] The present invention having the above-described structure has the following unique effects. According to the above method, the outer rim (2a) molding and tearing process are completed in one process, so even if the inner rim is finish-molded in a separate process, the manufacturing of automobile wheels in which the drop center is biased to one side In, rim equivalent part (12)
The time required to mold the rim to the rim cross section can be greatly reduced.

Further, in this forming method, since the rim-corresponding portion (12) may have a simple shape, it is possible to shorten the time required for the production including the forging step of the material (10) to be processed. .

[0014]

Embodiments of the present invention described above will now be described in detail with reference to the drawings. The embodiment shown in FIGS. 4 to 7 is for molding the rim cross section of an automobile wheel of a type in which the disc portion (1) is largely biased toward the outer rim (2a) side with respect to the rim cross section as shown in FIG. The present invention has been carried out, and a material to be processed (10) having a disk portion (1) on which a concavo-convex pattern portion (11) in a final finish state is formed is applied to first and second molds (3a) (3b). ), The rim-corresponding portion (12) of the material to be processed (10) is molded into the outer rim (2a) and the inner rim (2b) while being held under pressure.

Therefore, in this embodiment, the first mold (3a) rotatably supported above the second mold (3b) rotated by the rotation driving device (not shown) is vertically movable. Forming rollers (4) placed opposite each other and lateral to the boundary of these molds
And a spinning roller (40) for spinning is arranged at a position symmetrical to this. (See Figure 4)
In the first mold (3a), the surface shape of the end face (31) is made to match that of one of the uneven pattern parts (11), and the body part continuing from the peripheral edge part of the end face (31) to the first part is formed. 1 annular mold part (32)
The cross-sectional shape is made to match the inner contour of the cross-sectional shape from the deepest part (2c) of the drop center of the rim cross section to the edge of the outer rim (2a).

The other second mold (3b) has its end face (33)
While matching the other surface shape of the concavo-convex pattern portion (11), the body portion following this is made the second annular mold portion (34), and its cross-sectional shape is from the deepest portion (2c) of the drop center of the rim cross-section. It matches the inner contour of the cross-sectional shape up to the edge of the rim (2b). In addition, the cross-sectional shape of the drop center portion of the rim cross-section formed in this example is a triangular shape as a whole, and is steeply inclined with respect to the outer rim (2a) side and the other inner rim (2b) side. The hypotenuse is configured to gently incline. The intersection of these hypotenuses is the deepest part (2c). Further, the inner rim (2b) is composed of an inclined side portion (2f) on the inner rim (2b) side of the drop center and a seat portion (2d) continuous with the inclined side portion (2f).
And a rear flange portion (2e).

The forming roller (4) is vertically and horizontally driven while being supported in an upright posture and is pushed into the rim-corresponding portion (12) to perform splitting and forming as described above. In this embodiment, this forming roller (4) allows the entire inner rim (2a) of the drop center to be removed from the entire outer rim (2a).
The area up to a part on the b) side can be molded. For this reason, a maximum diameter portion (41) having a beak-shaped cross section is provided in the middle of the forming roller (4), and the outer peripheral body portion above this maximum diameter portion (41) has an outer rim forming portion (4a). ), And its cross-sectional shape matches the shape of the outer peripheral surface from the deepest part (2c) of the drop center in the rim cross section to the end of the outer rim (2a). Maximum diameter
The outer peripheral body below (41) becomes the inner rim molding (4b), and its cross-sectional shape is from the deepest part (2c) of the drop center to the inner rim (2b).
Part of b) (Sloping side (2f) on the inner rim side of the drop center)
Part of).

As the spinning roller (40), a normal type is adopted, and the second annular die part is driven by a drive device capable of controlling the attitude of the spinning roller and controlling the movement path.
Moved along (34). The cross-sectional shape of the rim equivalent part (12) of the material to be processed (10) adopted in the method of this embodiment is set to a substantially triangular shape that becomes thinner from the upper end to the lower side,
It is formed so as to largely project downward with respect to the disc portion (1).

The rim-corresponding portion (12) is divided into an outer rim-corresponding portion (12a) and an inner rim-corresponding portion (12b), but in this embodiment, the above-mentioned tear line (P). As shown in Fig. 4, there is a line that bends diagonally upward in a substantially J shape. The upper part of this cleavage line (P) is the outer rim equivalent part (12a), and the lower part is the inner rim equivalent part. It becomes (12b). This material (1
The rim equivalent part (12) of (0) is connected to the mold and forming roller (4) described above.
A method of forming a rim cross section using the above or the like will be described in detail below.

The material to be processed (10) is set so as to be fitted onto the second mold (3b) with the first mold (3a) separated from the second mold (3b) upward. In this state, the first mold (3a) is lowered to bring its end face (31) into contact with the disc portion (1). As a result, the disc part (1) is attached to the end face (31) and end face (33).
The work material (10) is clamped by and is held so as to rotate integrally with the second mold (3b).

When the second mold (3b) is rotated by the rotation driving device in this state, the mold and the material to be processed (10) rotate integrally. Then, as shown in FIG. 4, the forming roller (4)
After setting the maximum diameter part (41) of the rim equivalent part (12) to a predetermined position in the middle of the rim equivalent part (12), move the forming roller (4) so that it moves along the tear line (P). ). Then, as shown in FIG.
As shown in Fig. 4, the outermost rim molding part (4a) moves toward the first annular mold part (32) in a relative rotation state while the maximum diameter part (41) cleaves the rim equivalent part (12) up and down. , The inner rim molding part (4b) is the second
Similarly move to the upper side of the mold (3b).

At this time, the cleavage line (P) is set so that the maximum diameter part (41) once approaches the upper part of the second annular mold part (34) and then coincides with the deepest part (2c). Therefore, in the first half of the cleaving by the molding roller (4) and the molding process, the inner rim corresponding part (12b) is largely spread by the inner rim molding part (4b) along with the cleaving described above. Along with the outer rim equivalent part
The portion (12a) is slightly pushed up and deformed. (See FIG. 5-a) Then, in the latter half of this processing step, the second annular mold part (34)
And the inner rim molded part (4b) have a small distance, and the outer rim equivalent part (12b) is prevented from spreading below the material (the inner rim (2b) side). 12a) side is the first annular mold part (3
2) It is efficiently plastically deformed to the side. (See Fig. 5-b) Furthermore, when the maximum diameter part (41) finally coincides with the deepest part (2c), the first annular mold part (32) and the outer rim molding part (4a) have a rim cross-section space. And the parts corresponding to the outer rim (12a) are formed on the outer rim (2a). At this time, a part of the drop center on the inner rim (2b) side is molded at the same time. In this example, the inner rim molding part
Since (4b) is composed of a cross section parallel to the upper part of the second annular mold part (34) and an arcuate part at the lower end, the inner rim equivalent part (12b) is expanded as described above. Therefore, the lower end of the inner rim-corresponding part (12b) finally remains as an incompletely formed part (12c) having a water drop-shaped cross section as shown in FIG.

Then, in the present embodiment, following the above-mentioned processing steps, the forming roller (4) has an inner rim forming portion (4b) having a second annular mold portion (34) as shown in FIG. Top and inner rim (2b)
While maintaining the state of facing each other across the thickness of, the part of the incompletely molded part (12c) is molded as a part of the inner rim (2b) side of the drop center, Most of the inner rim side is finished.

Further, after this, as shown in FIGS. 6 and 7, the remaining incomplete portion is subjected to a spinning roll process using a spinning roller (40) to partially form the seat portion (2d) and the rear flange portion ( Molding to 2e) completes the molding of the entire rim cross section. In addition, in this embodiment, as shown in FIG.
The forming roller (4) and the spinning roller (40) are arranged at the positions facing each other across the boundary between the molds (3a) and (3b), and each of them has a predetermined path and a predetermined posture. Since each part is pressurized, each molding process can be performed continuously.

Therefore, not only the cleaving of the rim corresponding portion (12) and the molding of the outer rim (2a) and the drop center portion can be performed at the same time, but also the step of molding the incompletely molded portion (12c) into the inner rim (2b). Therefore, the time required for molding the rim cross section can be further shortened. In the above embodiment, the whole disc portion (1) is clamped by the first and second molds (3a) (3b), but as shown in FIG. 9, only the peripheral portion of the disc portion (1) is an end surface. It is also possible to adopt a structure in which the peripheral edge portion of (31) and the peripheral edge portion of the end face (33) are held under pressure.

In this case, as shown in the figure, a concave portion (35) wider than the range corresponding to the concave-convex pattern portion (11) of the disk portion (1) and deeper than the protrusion degree of the concave-convex portion is formed. First
A similar recess (36) is formed on the end surface (31) of the mold (3a).
May be formed on the end surface (33) of the other second mold (3b). When using the first and second molds (3a) and (3b) configured as described above, a rim body of a so-called two-piece type automobile wheel can be processed by the same method. The rim body is composed of a rim portion and a mounting flange, and the disc portion (1) is screwed to the mounting flange. ), The mounting flange is projected to the inner peripheral side, and the mounting flange is clamped by the outer peripheral region of the recessed portion (35) of the end face (31) and the outer peripheral region of the end face (33).・ Second mold (3
By means of a) and (3b), the material to be processed (10) can be held. (Refer to FIG. 10) When forming the entire range from the deepest part (2c) to the edge of the inner rim (2b) by spinning roll processing, the forming roller (4) is as shown in FIG. In addition, it may have a shape including only the outer rim molding portion (4a).

Further, the outer peripheral surface of the rim-corresponding portion (12) of the material to be processed (10) of the above-mentioned embodiment has a cylindrical shape, and as shown in FIG. 10, this portion corresponds to the outer rim-corresponding portion (12a). ) Side end portion may be provided with a flange portion (13). In this case, since the flange portion (13) is projected outward in the radial direction in advance, the cleavage depth can be reduced correspondingly, and the processing time required for forming the outer rim (2a) can be shortened.

Further, in any of the above-mentioned embodiments, the range from the drop center portion of the rim portion to the end portion of the inner rim (2b) is a smooth inclined surface, but the drop center portion is locally formed as shown in FIG. The shape may be concave. In this case, the inner rim forming part (4b) of the forming roller (4) is the inclined side part that connects the deepest part (2c) of the drop center and the seat part (2d).
It comprises a first tapered barrel portion (4c) having a cross section parallel to (2f), and a second tapered barrel portion (4d) which is continuous with this and has a taper smaller than the first tapered barrel portion (4c). And forming rollers (4)
Roll processing by the same procedure as the above-mentioned embodiment, from the outer rim (2a) and the drop center to the seat portion (2d)
Mold up to a part of. (See FIGS. 12-a to d) After that, the unformed portion of the seat portion (2d) and the rear flange portion (2
e) is finished by another roll process. (See FIG. 12-e) Although the second taper body portion (4d) may be omitted, the second taper body portion (4d) is not provided in the above case at the initial tearing stage of the processing step. Is the inner rim (2b) side rim equivalent part (12)
Since it spreads toward the inner rim (2b) end while suppressing the flow of the inner rim (2b) (Fig. 12-b), the workability is improved during the subsequent molding step of the inner rim (2b). . Further, in the above, the first tapered barrel portion (4c) is parallel to the inclined side portion (2f), but it may be tapered larger than the inclined side portion (2f).

Needless to say, in any of the above embodiments, the volume of the rim corresponding portion (12) is set to be slightly larger than that of the rim portion finally formed. Furthermore, in any of the above-described embodiments, the inner rim is
In the case where the (2b) side is reattached to another mold for spinning processing and is processed and formed, the inner rim forming die part (34) is provided on the outer peripheral body of the second die (3b). There is no need to have one.

Further, in the present embodiment, the material to be processed (10)
The first and second molds (3a) and (3b) for holding and holding the are arranged so as to face each other in the vertical direction, but they may be arranged so as to face each other in the left and right. In this case, an auxiliary device that supports or drives each of the above parts is also provided correspondingly. In the above-described embodiment (shown in FIGS. 4 to 7), the cross section of the upper part of the inner rim forming part (4b) of the forming roller (4) is parallel to the second annular mold part (34). However, as shown in FIG. 8, this may be a taper larger than the second annular mold portion (34).

Further, in the above embodiments, the cleavage line (P) is not necessarily limited to the J-shape, and for example, L
It may have a letter shape (see FIG. 8). This cleavage line (P) is
It is determined by the relationship between the cross-sectional shape of the rim equivalent portion (12) and the shape of the forming roller (4).

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a state of the initial stage of dehiscence in a conventional method.

FIG. 2 is a cross-sectional view of a state in which a dehiscence is completed in a conventional method.

FIG. 3 is a cross-sectional view at the completion of roll forming processing in the conventional method.

[Fig. 4] Cross-sectional view of the work material (10) set

FIG. 5 is a cross-sectional view of an essential part showing a processing step by a forming roller (4)

FIG. 6 is a cross-sectional view showing a state during spinning of the end portion of the inner rim (2b).

FIG. 7 is a cross-sectional view of the wheel when processing is completed.

FIG. 8 is a sectional view showing another form of the inner rim forming part (4b) of the forming roller (4).

FIG. 9 is a cross-sectional view when using other types of first and second molds (3a) and (3b).

FIG. 10 is an explanatory view when the shape of the rim equivalent part (12) is changed.

FIG. 11 is a cross-sectional view when another forming roller (4) is used.

FIG. 12 is a cross-sectional view of a main part when processing a rim cross section in which a drop center is recessed.

[Explanation of symbols]

 (10) ・ ・ ・ Material to be processed (12) ・ ・ ・ Rim equivalent part (1) ・ ・ ・ Disk part (3a) ・ ・ ・ First mold (3b) ・ ・ ・ Second mold (2a) ・..Outer rim (32) ... First annular mold part (4) ... Molding roller (41) ... Maximum diameter part (4a) ... Outer rim molded part (4b) ... Inner rim Molding part (2f) ・ ・ ・ Slope side

Claims (3)

[Claims] 1. A method for forming a rim-corresponding portion (12) of a workable material (10) capable of being plastically processed into a rim portion of an automobile wheel by a combination of cleaving and roll forming. Is a structure in which the disc portion (1) or the mounting flange portion is integrally formed on the inner circumference of the rim-corresponding portion (12) that is raised in an annular shape, and the inner circumference of the rim-corresponding portion (12) of the workpiece material (10) is Molding supported by a pair of first and second molds (3a) and (3b) while holding the area between them and rotating relative to them on the outer periphery of the boundaries and movably toward the boundaries. Laura (4)
Is disposed on the outer peripheral body portion on the end face side of the first mold (3a),
A first annular mold part (32) adapted to the cross section of the outer rim (2a) is formed, and the forming roller (4) is formed from the maximum diameter part (41) to one end of the outer rim forming part (4). 4a) and the outer peripheral surface of this outer rim molding part (4a) matches the shape from a part of the drop center to the end of the outer rim (2a), and the maximum diameter part (41) of the molding roller (4) By pushing the outer rim forming portion (4a) into the rim-corresponding portion (12) along a predetermined path so that the outer rim forming portion (4a) finally faces the first annular mold portion (32), thereby forming a cross section of the outer rim (2a). Method for forming rim of automobile wheel. 2. A part of the rim equivalent part (12) is finished by a forming roller (4) from a part of the drop center to the outer peripheral surface of the end part of the outer rim (2a), and then the other part is A cross section corresponding to the roll is finished by roll processing.
A method for forming a rim portion of an automobile wheel according to item 1. 3. The forming roller (4) comprises an inner rim forming part (4b) following the outer rim forming part (4a), and continues to the maximum diameter part (41) of the inner rim forming part (4b). The method for forming a rim portion of an automobile wheel according to claim 1 or 2, wherein a predetermined range is a taper portion, and the taper of the taper portion is set to be larger than the inclined side portion (2f) on the inner rim side of the drop center. .