JPH0320287B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a molding apparatus for forming tires and wheels for, for example, automobiles, and more particularly to a molding apparatus for forming tire wheels into an endless shape using a pipe material.

[Conventional technology]

For example, conventional methods for forming tires and wheels for automobiles, etc. include methods of integrally forming them by casting or forging and forming them by cutting, and methods of forming them in the same cross-sectional shape as the outer circumferential surface of the tire wheel. There are two methods: one method involves curling a strip plate that has been processed into a shape, spot welding both ends of the strip, and performing roll processing, and one method of integrally forming a pipe material by expanding the openings at both ends with a press. Proposed.

[Problem that the invention seeks to solve]

However, among the above-mentioned methods, the method using pipes as a material makes it possible to obtain seamless tire wheels, but on the other hand,
The problem is that it cannot be formed in one stroke of the press (if it is formed in one stroke of the press, the pipe material will buckle or the opening will curl outward). have Therefore, when forming tire wheels using conventional pipe materials, several press strokes (3 to 4 strokes) are required.
The molding process is performed in separate steps, but the reality is that this results in significant time inefficiency and economic waste.

The present invention is an attempt to improve the above-mentioned conventional problems by molding a seamless tire wheel using a single mold and in one stroke of a press. The problem to be solved lies in making it possible to do so. That is, the present invention enables the pipe material to be pushed and expanded without buckling or curling in the process in which the ram descends and the upper and lower inner molds come into contact with each other. The above-mentioned problems are solved by making it possible to bend and deform the expanded pipe material along the molded convex surface in the process of contacting and compressing the ring spring. The specific means and effects are as follows.

[Means for solving the problem] At least one of the upper and lower inner molds forming a molding convex surface on the outer periphery is formed into a closed cylindrical shape such that the molding convex surface is divided along the axial direction. It is divided into a split mold and a plurality of annular split molds arranged on the outside thereof, and each split mold is fitted onto the split mold located inside the split mold, and each split mold is attached to both the inner and outer sides of each adjacent split mold. The connection is made so as to be movable back and forth along the axial direction through the engagement of the protrusions and grooves formed in correspondence with each other on the circumferential surface.

Among the plurality of split molds, the outermost split mold is fixed to the anvil or ram of the press machine, while a spring is interposed between the split mold located in the center and the anvil or ram, and the spring Due to the elastic force of the split molds, the split molds other than the outermost mold are usually lifted up from the anvil or the ram, and a gap is formed between the molding convex portions of each split mold. The molding convex portions of each split mold are connected in a continuous manner by compression of the spring.

[Operation] A process in which the ram descends and the upper and lower inner molds come into contact.The ram is provided between each split mold, and the molding convex surface is formed with a gentle slope, so that the pipe material buckling the middle part of
It is possible to temporarily expand the opening into a gentle curve without curling it.

The upper and lower inner molds come into contact and compress the ring spring. As the spring is compressed, each split mold is compressed in the axial direction, and the gap between each split mold disappears. The molding convex surfaces of the mold are connected in a continuous manner to form the final molding convex shape, and the pipe material, which was expanded with a gentle slope in the above process, can be further expanded with a steeper slope by this molding convex surface. . That is,
It is possible to obtain a state in which the pipe material is secondarily bent and deformed along this continuous forming convex surface.

〔Example〕

Specific embodiments of the present invention will be described below with reference to illustrative drawings.

1 to 3 are drawings showing the first embodiment, and in each drawing, 1 is an anvil fixed to the frame of a press machine, and 2 is an anvil that is attached to the frame and faces the anvil 1, and can move up and down in the vertical direction. The lower inner mold 3 is attached to the anvil 1, and the ram 2 is attached to the anvil 1.
Upper inner molds 4 are attached to the upper inner molds 4 so as to face each other. The lower inner mold 3 has a molding convex surface 5 formed on its outer periphery and has three split molds in a concentric circle, namely, a split mold 3A located in the center (hereinafter referred to as "center split mold 3A"). ), a split mold 3B located on the outer periphery (hereinafter referred to as "outer periphery split mold 3B"),
It is divided and formed into a split mold 3C (hereinafter referred to as "intermediate split mold 3C") interposed between both split molds 3A and 3B. Therefore, the center split mold 3A is the main body part 3A-1.
The main body part 3A-1 and the outer frame part 3A-2 have a plurality of brackets 3A extending in the radial direction at the bottom thereof. -3. And the main body part 3A-1 of the concentric split mold 3A
A ring spring 6 is interposed between the anvil 1 and the anvil 1, and its bottom is normally raised above the anvil 1, that is,
A gap 7 is formed between the center split mold 3A and the anvil 1. Further, an annular groove 8 is carved on the outer circumferential surface of the central split mold 3A, while an annular groove 8 is carved on the inner circumferential surface of the intermediate split mold 3C.
An annular protrusion 9 is protrudingly provided opposite to the annular groove 8, and is provided so as to engage with the annular groove 8 with an appropriate amount of play. Further, an annular groove 10 is carved on the outer peripheral surface of the intermediate split mold 3c, while an annular convex strip 11 is projected on the inner peripheral surface of the outer peripheral split mold 3B, facing the annular groove 10. It is provided so as to engage with the annular groove 10 with an appropriate amount of play. In this way, the intermediate split mold 3C is engaged with the center split mold 3A with an appropriate amount of play, and,
By engaging the outer circumference split mold 3B with the middle split mold 3C with an appropriate amount of play, the middle split mold 3C is always interlocked with the center split mold 3A, and its bottom part is It is raised above the anvil 1,
That is, a gap 12 is formed between the center split mold 3A and the middle split mold 3C, and a gap 13 is formed between the middle split mold 3C and the outer peripheral split mold 3B.

On the other hand, the upper inner mold 4 attached to the ram 2 side is also formed in the same manner as the lower inner mold 3 described above.

FIG. 4 is a drawing showing the second embodiment,
An outer frame portion 3A-2 is provided on the outer periphery of the lower inner mold 3 and the upper inner mold 4.
Instead, an outer mold 14 is provided so as to surround both inner molds 3 and 4. And the same outer mold 14 has both inner molds 3 and 4.
A molded concave surface 15 is formed in correspondence with a molded convex surface 5 to be formed.
is formed and divided into a plurality of split molds with an appropriate split angle, and each split mold is provided so as to be freely movable forward and backward in the radial direction in conjunction with the vertical movement of the ram 2. That is, as the ram 2 descends, each split mold moves toward the center to set the molding concave surface 15, and conversely, as the ram 2 rises, each split mold moves toward the center. It is provided so that a state can be obtained in which the molded concave surface 15 in the set state is disassembled by moving in the direction of separation.

Next, its effect will be explained.

In the first embodiment shown in FIGS. 1 to 3, FIG. 1 shows the ram 2 in the raised position and the upper inner mold 4.
This drawing shows a state in which the pipe material W is set between the upper and lower inner molds 3, and when the ram 2 is in the raised position, both the center split molds 4A, 3A are installed in both the upper and lower inner molds 4, 3. are raised above the ram 2 and anvil 1 by ring springs 6, 6, respectively. In addition, both middle part split molds 4C and 3C are linked with center part split molds 4A and 3A, and are also raised above the ram 2 and anvil 1, that is, both center part split molds 4A and 3A and both middle part split molds There are gaps 12, 12 between the molds 4C and 3C, and both middle part split molds 4C and 3C.
There is a gap 13, 13 between the outer peripheral split molds 4B and 3B.
are in a state of being formed respectively. In other words, the molding convex surfaces 5, 5 formed on both the upper and lower inner molds 4, 3 have gaps 12, 13 interposed therebetween, so that a gentle slope is obtained accordingly. By lowering the ram 2 with the pipe material W set between the upper inner mold 4 and the lower inner mold 3 in this way, both the upper and lower inner molds 4, 3 are inserted through the upper and lower openings of the pipe material W.
enters and forcibly expands the pipe material W. More specifically, the pipe material W is sequentially expanded at each ridge part b because the molding convex surfaces 5, 5 formed on the upper and lower inner molds 4, 3 have a gentle slope due to the gaps 12, 13. A state is obtained in which the recessed portion a is easily entered along the recessed portion a, and the opening portion at the tip abuts against the outer frame portions 4A-2 and 3A-2.

In addition, the openings at both ends of the pipe material W are the outer frame portion 4A.
-2, 3 It is not necessarily necessary to hit A-2 at the same time, but even if there is a time lag, the pipe material W can be distributed to both the upper and lower inner molds 4, 3, and the effect of pushing and spreading can be obtained. I can do it. And in this way, the tip opening part of the pipe material W is the outer frame part 4.
By continuing to lower the ram 2 in the state in which it hits A-2 and 3A-2 and the upper and lower center split molds 4A and 3A are in contact (the state shown in Fig. 2), the ring spring 6, 6 are compressed, the center split dies 4A, 3A move back toward the ram 2 and the anvil 1, and the intermediate split dies 4C, 3C move in conjunction with the center split dies 4A, 3A, and the ram 2. and the action of retreating toward the anvil 1 direction, that is, until now, the center split molds 4A, 3A and the intermediate split molds 4C,
The gaps 12 and 13 that were formed between 3C and between the intermediate split molds 4C and 3C and the outer peripheral split molds 4B and 3B are eliminated, and as a result, the molding convex surface with the gaps 12 and 13 interposed as described above is eliminated. 5, 5, the pipe material W, which has been temporarily bent and deformed with a gentle slope, can be further bent and deformed to a steep slope along the molding convex surfaces 5, 5 through pressure in the axial direction. At the same time, the outer frame portion 4A- is interlocked with the main body portions 4A-1 and 3A-1 in the center split molds 4A and 3A.
By retracting 2 and 3A-2, the openings (ears) at both ends of the pipe material W are bent and deformed in the retracting direction, that is, the forming state shown in FIG. 3 is obtained.

In addition, in the second embodiment shown in FIG. 4, the outer mold 14 moves toward the center in conjunction with the lowering of the ram 2, that is, each split mold of the outer mold 14 in a dispersed state A state is obtained in which the molds are set so as to surround both the upper and lower inner molds 4 and 3. In this way, with the outer mold 14 surrounding both the upper and lower inner molds 4, 3, the forming action as shown in the first embodiment is obtained, so that the pipe material W can be molded into the upper and lower inner molds 4, 3. It is possible to obtain an operational state in which the molding process is performed in a state in which the molding surfaces 5, 5 are in almost complete contact with each other along the molding convex surfaces 5, 5 formed on the molding surfaces 5, 5.

〔Effect of the invention〕

The present invention is constructed as described above, and includes:
With the above configuration, it is now possible to mold tires and wheels using a single mold and in one stroke of the press, and this makes it possible to mold tires and wheels in a shorter time compared to conventional molding methods. In addition, it has become possible to mold tires and wheels at low cost.
In other words, it has become possible to significantly improve the workability.

[Brief explanation of the drawing]

1 to 3 are drawings showing a first embodiment, in which FIG. 1 is a sectional view of a tire wheel molding apparatus according to the present invention, and FIGS. 2 and 3 are a lower inner mold portion. FIG. 3 is an enlarged cross-sectional view showing the operating state of the
FIG. 4 is a drawing showing the second embodiment, and is an enlarged sectional view showing the operating state of the outer mold and the lower inner mold portion. 1... Anvil, 2... Ram, 3... Lower inner mold, 3A
...Central split mold, 3B...Perimeter split mold, 3C
...Intermediate split mold, 3A-1...Body part, 3A-
2... Outer frame, 3A-3... Bracket, 4...
Upper inner mold, 4A...center split mold, 4B...outer periphery split mold, 4C...middle split mold, 4A-1...main body, 4A-2...outer frame, 4A-3... Bracket, 5... Molded convex surface, 6... Ring spring, 7... Gap, 8... Annular groove, 9... Annular convex strip, 10...
Annular groove, 11... Annular protrusion, 12... Gap, 1
3... Gap, 14... Outer mold, 15... Molding concave surface.

Claims (1)

[Claims] 1 At least one of the upper and lower inner molds forming a molding convex surface on the outer periphery is a covered cylindrical split mold such that the molding convex surface is divided along the axial direction, and a plurality of molds arranged on the outside thereof. Each split mold is formed into annular split molds, and each split mold is fitted onto the split mold located inside the split mold, and each split mold is formed so as to correspond to both the inner and outer circumferential surfaces of the adjacent split molds. Through the engagement of the protrusions and grooves, they are connected so that they can move forward and backward along the axial direction, and the outermost split mold is fixed to the anvil or ram of the press machine, while the split mold located in the center and the above-mentioned A spring is interposed between the anvil or the ram, and the elastic force of the spring causes the split molds other than the outermost split mold to rise above the anvil or the ram, creating a gap between the molding convex portions of each split mold. A tire wheel molding device comprising: a molding convex surface portion of each split mold being connected in a continuous manner by compression of the spring by pressurization of a press machine.