JPH042501A - Wheel for motorcycle - Google Patents

Abstract

PURPOSE:To improve joining of a spoke and a hub by joining both the members to each other on the same axis, setting a welded line of both the members so that it is extended in the circumferential direction of these members to secure sufficient length of the welded line even when the outer diameter of the hub is small. CONSTITUTION:The wheel 1 of a motorcycle has a spoke 2 made of sheet metal, and a boss 4 fitted and mounted on the axle is forced into a through hole 3 formed on the axis of the spoke 2, and welded. The spoke 2 is dented so that its one side face in the axial direction on the center part becomes a circular recessed part 5, the hub 7 is shaped into a cylinder with bottom, and its bottom is pressed into the recessed part 5 on the same axis as the spoke 2. Furthermore, a circular through hole 8 is formed on the axis of the hub 7, and the boss 4 is forced into the through hole 8, and welded. In this case, the inside bottom face 5a of the recessed part 5 and the outside bottom face 7a of the hub 7 are joined and come into a face-contact with each other, both the members are welded to each other along a junction-line, and the welded line 10 is extended in the circumferential direction of the spoke 2.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a wheel for a motorcycle.6 (Prior Art) A wheel for a motorcycle includes plate-shaped spokes and a cylindrical hub with a bottom, In many cases, the outer bottom surface of the knob is joined to the spoke, and the two members are joined together at this joint by spot welding.

(Problems to be Solved by the Invention) By the way, the wheels of a motorcycle are subjected to a large impact from the road surface while the vehicle is running, and therefore, it is desirable that the bonding strength between the spokes and the hub be as high as possible.

Therefore, it is possible to weld as many points as possible between the spokes and the hub, but in this case, there is a risk that both of them will become hot during welding and will be thermally deformed, resulting in excessive deformation of the product after welding. be.

(Object of the Invention) The present invention was made in view of the above-mentioned circumstances, and it is possible to achieve a high-strength connection between spokes and a hub when welding these two members together, and also to The purpose is to prevent deformation of products.

(Structure of the Invention) A feature of the present invention for achieving the above object is that the outer bottom surface of a bottomed cylindrical hub is joined to the plate-shaped spoke on the same axis, and the two members are welded together. Both members are welded to each other by a high-energy-density beam that is irradiated from the outside of one of the members so that a line extends in the circumferential direction.

(for production) The effects of the above configuration are as follows.

The spokes 2 and the hub 7 are coaxially joined to each other, and weld lines 10 of these two members extend in the circumferential direction.

Therefore, even if the outer diameter of the hub 7 is small, the weld line 10
A sufficient length can be obtained, and both members can be joined without directionality.

Further, the above-mentioned welding is performed using a high-energy-density beam 11 irradiated from the outside of one of the two members. Therefore, during the above welding, the beam 11
The other member, which is not directly irradiated, is prevented from becoming high temperature, and in other words, the other member is prevented from being thermally deformed.

Therefore, even if the one member to which the beam 11 is directly irradiated becomes hot and thermally deforms, this thermal deformation is prevented by the other member.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In the figure, 1 is a wheel of a motorcycle, and this wheel 1 has spokes 2 made of sheet metal. A circular through hole 3 is formed above the spoke 2, and this through hole 3 has the following features:
A boss 4 that fits and is attached to the axle is press-fitted and welded.

The spokes 2 are recessed in the axial direction and the side surface of the central portion thereof to form a circular recess 5, and this recess 5 is also formed coaxially with the spoke 2.

Reference numeral 7 designates a hub made of sheet metal, which has a cylindrical shape with a bottom, and is coaxial with the spokes 2, and its bottom is press-fitted into the recess 5.

The outer bottom surface 7a of the hub 7 is in surface contact with the inner bottom surface 5a of the recess 5. Further, a circular through hole 8 is formed on the axis of the hub 7, and the boss 4 is press-fitted into this through hole 8 and welded.

The inner bottom surface 5a of the recess 5 and the outer bottom surface 7a of the hub 7 are joined in a surface contact manner, and both members are welded to each other at this joint. The welding line 10 extends in the circumferential direction of the spoke 2, and the welding in this case is performed by a high-energy-density beam 11 irradiated from the outer surface side of the spoke 2, which is the side opposite to the hub 7. . Also,
A rim 12 is fitted onto the outer peripheral edge of the spokes 2 and welded thereto.

Note that the hub 7 is used as a drum portion of a drum brake.

In FIG. 1, reference numeral 14 denotes a welding device for welding the spokes 2 and the hub 7 together using the beam 11.

This welding device 14 has a rotary table 16 that is rotatable in the direction of arrow R in the figure around a vertical rotation center 15, and a support base 17 is screwed onto this rotary table 16. Further, the support stand 17 is located coaxially with the rotation center 15.
A cylindrical support block 18 is removably screwed onto the top. The hub 7 can be fitted to and removed from the support block 18, and when the hub 7 is fitted to the support block 18, the hub 7 is automatically positioned coaxially with the rotation center 15. ing.

A lift shaft 19 is provided above the rotary table 16 on the same axis as the rotation center 15, and a presser body 22 is supported on the lower end of the lift shaft 19 via a bearing 21 so as to be rotatable around the rotation center 15. ing.

Further, a torch 23 for irradiating the beam 11 toward the outside of the elevating shaft 19 is provided so as to be movable up and down.

Next, the procedure for forming the hub 7 will be explained with reference to FIG. 1. First, the spokes 2, bosses 4, and hub 7 are press-fitted into each other as shown in the figure. Then, the hub 7 is fitted into the support block 18 with the spokes 2 at the top and the hub 7 at the bottom in a horizontal position. Next, the lifting shaft 19 is lowered, and the upper surface of the spoke 2 is pressed down with the presser body 22 as shown in the figure.
and the hub 7 are sufficiently crimped.

After that, the torch 23 is lowered and the beam 11 is applied from the outside of the spoke 2 to the joint between the spoke 2 and the hub 7.
irradiate. At this time, the rotating daple 16 is rotated, and welding is performed around the rotation center 15. When this welding is performed on the entire circumferential direction, the rotary table 16
At the same time, the spokes 2 and the knob 7 are taken out from the welding device 14 by stopping the rotation of the spokes 2 and the knob 7 by raising the elevating shaft 19 and the torch 23.

Next, the spokes 2, the hub 7, and the post 4 are fillet welded, and then the inner surface of the knob 7 is cut,
Furthermore, the rim 12 is welded to the spokes 2. Then, the molding of the wheel 1 is completed.

Note that the beam welding is, for example, laser beam welding or electron beam welding. Further, the weld line IO may be continuous in the circumferential direction or may be discontinuous. Further, in the above embodiment, the beam 11 is irradiated from outside the spokes 2, but the beam 11 may be irradiated from outside the hub 7.

(Effects of the Invention) According to the present invention, the spokes and the hub are joined to each other coaxially -F, and the weld lines of these two members extend in the circumferential direction, so even if the outer diameter of the hub is small, The welding line can be sufficiently long, and both members can be joined without directionality. Therefore, these two members can be joined with high strength.

Additionally, since the above welding is performed using a high-energy-density beam that is irradiated from the outside of one of the two members, the other member, which is not directly irradiated with the beam, becomes hot during the welding process. This prevents thermal deformation from occurring in the other member.
Even if one of the members directly irradiated with the beam reaches a high temperature and attempts to undergo thermal deformation, this thermal deformation is blocked by the other member, and as a result, no deformation occurs in the product after welding. In other words, a wheel with high dimensional accuracy can be obtained.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is an overall side sectional view, and FIG. 2 is a view of the wheel taken along the line II--II in FIG. 1. ■...wheel, 2...spoke, 7...hub, IO...welding line, 11...beam. Figure 2

Claims (1)

[Claims] 1. Coaxially with the plate-shaped spoke, the outer bottom surface of a bottomed cylindrical hub is joined to this spoke, and one of the above-mentioned two members is joined so that the weld line of both the above-mentioned members extends in the circumferential direction. A motorcycle wheel in which both of the above members are welded together by a high-energy-density beam irradiated from the outside of the members.