JPH046586B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a steering wheel for an automobile, and more particularly to an improvement in a coupling mechanism for coupling a wheel ring to a steering shaft.

Prior Art In the steering wheel of an automobile, conventionally, as shown in FIG.
A short arc sub-ring 2 is combined with the wheel ring 6 to form an annular wheel ring 6.The weaker sub-ring is placed on the driver's side to weaken the impact force in the event of an accident, and this wheel ring 6 is attached to the steering shaft. (not shown) via spokes 4, 4. The main ring 1, sub-ring 2 and spokes 4, 4 are connected by welding each end 1a of the main ring 1 to the bent end 4a of each spoke 4, respectively, as shown in the figure, and the end of the sub-ring 2. The portions 2a, 2a are welded and connected to the bent portions 4b, 4b of the spokes 4, 4, and the other end portions 4c,
4c is fixed to the boss plate 3 by welding. As described above, in the past, since each connecting portion was fixed by welding, distortion was likely to occur due to the heat during welding, and the installation accuracy was poor. In particular, since the rings 1 and 2 and the spokes 4 and 4 are not on the same plane and the spokes 4 and 4 are connected at an angle, the amount of distortion tends to increase, and furthermore, when welding the spokes 4 and the boss plate 3, There were problems in that the amount of distortion due to heat was likely to increase and the reliability of the mounting strength was low.

OBJECT OF THE INVENTION An object of the present invention is to provide an automobile steering wheel that does not cause distortion in the connections between the spokes, boss plates, and bosses, improves mounting accuracy, and improves reliability of mounting strength. It is about providing.

Structure, Operation, and Effects of the Invention In order to achieve the above object, the present invention is configured to eliminate mounting errors and improve mounting accuracy by integrally forming spokes, bosses, and boss plates as one component. did. That is,
The boss part that connects to the steering shaft, the boss plate part that protrudes from the boss part, and the spoke part that connects the tip part that protrudes from the boss plate part to the steering wheel ring are made into one part by forging that allows control of the wall thickness. It was constructed as an integral part.

According to the above structure, since the boss part, the boss plate part, and the spoke part can be integrally molded as one part by forging, there is no need to attach the parts such as the boss part and the boss plate part to each other, and there is no possibility of installation errors. This does not occur, the arrangement relationship between each member can be maintained with high precision, and the attachment strength between each member is increased, so that reliability can be improved. In other words, in the past, the boss, boss plate, and spoke were manufactured separately and attached to each other by welding, but the heat generated during welding can distort the diameter of the attachment hole in the boss, for example. At the same time, it was difficult to perform the installation work with high precision. In contrast, the present invention can eliminate the above disadvantages as described above.

In addition, installation work between each component is no longer required,
Furthermore, since the number of parts is reduced, manufacturing and installation costs can be reduced.

Furthermore, there are fewer restrictions on the mutual arrangement of the members than when they are attached by welding, and they can be freely designed.

The forging process, which allows for control of wall thickness, allows the boss section, boss plate section, and spoke section to be integrally constructed as one component, making it possible to change the wall thickness, increasing the wall thickness in areas where strength is required. can be formed. Therefore, there is no need for further special processing for reinforcement.

Therefore, as mentioned above, the intended purpose can be achieved.

EXAMPLES The present invention will be specifically described below based on examples shown in FIG. 2 and below.

The steering wheel according to this embodiment has a second
As shown in the figure, a steering wheel 29 is attached to the upper end of a steering shaft (not shown) via a wheel attachment member 11.

The wheel mounting member 11 is made of a forged iron product, and protrudes from the boss portion 13 to form a boss plate portion 14.
A pair of spoke portions 1 rise up at a certain angle from both ends of the upper surface and are open to each other at a certain angle.
2, 12 are formed.

The boss portion 13 passes through the center of the boss plate portion 14 and has a through hole 15 at the center, and has serrations 19 on the inner peripheral surface of the through hole 15.
It consists of a thick cylindrical body that forms a

Further, the boss plate portion 14 is in the shape of a flat plate, and there are mounting holes 16, 1 in the vicinity of the boss portion 13.
6 is inserted through the steering shaft, and the boss plate portion 14 is connected and fixed to the upper end of the steering shaft using screws or the like. A resin plate 21 is attached to the lower part of the boss plate part 14, or a resin plate 21 is attached to the lower part of the boss plate part 14.
4 is integrally molded with resin to form a plate-shaped portion, and the horn cover 7 and the like are attached to the upper part of the boss plate portion 14.

Therefore, the connecting portion at the upper end of the steering shaft is fitted into the through hole 15 and the serrations 19, and the shaft and the wheel mounting member 11 rotate integrally.

Further, the spoke portions 12, 12 are each made of a round bar, and are formed so as to rise diagonally upward from the boss plate portion 14 at a certain angle, symmetrically with respect to a plane that bisects the boss plate portion 14. The main ring 2 of the wheel ring 29 is attached to each end thereof.
The wheel ring 29 is supported on the boss plate portion 14 by connecting one end of a T-shaped elbow 27 connecting the wheel ring 5 and the sub-ring 26.

The wheel mounting member 11 is manufactured by forging as shown in FIG.

That is, as shown in FIG. 3a, the iron round bar 17 is cut to a predetermined size.

Next, the central portion of the round bar 17 is locally heated to, for example, 800° C. or higher using a high-frequency heating device or the like. The subsequent steps are performed using this residual heat.

Next, as shown in FIG. 3b, upsetting forging is performed to form a spherical portion 18 at the center of the heated round rod.

Next, as shown in FIG. 3c, the spherical part 1 is
8, the round rod 17 is bent in a dogleg shape at a constant angle in plane symmetry with respect to the plane that bisects the spherical portion 18, thereby forming the spoke portions 12, 12.

Next, as shown in FIG. 3 d and FIG. 4 a,
The boss plate part 14 is formed by flattening the spherical part 18 heated to about 700°C, and a thick part is made to protrude from the lower surface of the boss plate part 14 to form the boss part 13. A small concave portion 20 for a hole is formed in the boss portion 13.

Then, as shown in FIG. 3e and FIG. 4b,
The boss plate part 14 drops to about 300 to 400 degrees Celsius,
After passing through a brittle region of 600° C. to remove the strain caused by the forging, the small recess 20 formed in the boss portion 13 is recessed in the axial direction, and the boss portion 13 is stretched relative to the boss plate portion 14. Forged and shaped. On the other hand, the spoke portions 12 are formed by further bending forging between each spoke portion 12 and the boss plate portion 14.

Next, as shown in FIGS. 3f and 4c, a through hole 15 is formed by passing through the recesses 20, 20 of the boss portion 13, and a serration is formed on the inner peripheral surface of the through hole 15 by press working. 19, a mounting hole 16 is provided through the boss plate portion 14, and further trimming is performed.

In this way, the wheel mounting member 11 is manufactured.

This wheel mounting member 11 is attached to each spoke portion 1.
2 through the T-shaped elbow 27 to the wheel ring 29
After the steering shaft connecting portion is connected to the boss portion 13, the steering shaft connecting portion is fitted to the boss portion 13, and the boss plate portion 14 is fixed to the upper end of the shaft. The wheel ring 29 is formed from a circular metal tube such as iron, and the ring 29 is crushed from one end to about 1/3 of the total length to form a flat sub-ring 26. And the remaining 2/3 is the main ring 25
and the ends 25a, 26 of both rings 25, 26
A is made continuous to form a ring shape. Instead of fully crushing the sub-ring 26 in the direction where strength is not required as described above, the sub-ring 26 may be partially crushed and then having an elongated hole in the circumferential direction to weaken its strength.

Further, the T-shaped elbow 27 includes a pair of cylindrical ring fitting parts 27a and 27b, and a pair of cylindrical ring fitting parts 27a and 27b.
It consists of a cylindrical spoke fitting part 27c protruding from the tube outer wall surface between a and 27b. Then, the end of the main ring 25 and the end of the sub-ring 26 are fitted into each ring fitting part 27a, 27b, respectively, and caulking is performed from the entire circumferential direction of each fitting part 27a, 27b. The spoke part 1 is attached to the spoke fitting part 27c.
The ends of the two are fitted together and caulked from the entire circumferential direction of the spoke fitting part 27c to connect the main ring 25 and the sub ring 26 to form the wheel ring 29, and the wheel ring 29 is attached to the spoke part. It is connected to the boss plate portion 14 and, thus, to the steering shaft via the boss plate portion 12, 12.

According to the above embodiment, the boss portion 13, the boss plate portion 14, and the spoke portions 12, 12 are integrally formed as a single piece by forging, so there is no need to attach each member to each other. As a result, there is no installation error, and the positional relationship between each member can be maintained with high precision, and since it is made into one piece by forging, the reliability of the strength of each member attachment part can also be improved. Therefore, for example, in the past, the attachment strength between the boss plate and the spokes was unreliable, so it was necessary to make the boss plate larger, and a horn cover, etc., was attached to the boss plate. According to the embodiment, since the boss plate portion 14 and the spoke portions 12 can be formed integrally by forging, the boss plate portion 14 can be made smaller, and the plate 21 to which the horn cover etc. is attached can be made of resin. This allows the overall weight to be reduced.

In addition, installation work between each component is no longer required,
Furthermore, since the number of parts is reduced, manufacturing and installation costs can be reduced.

Furthermore, there are fewer restrictions on the mutual arrangement of the members than when they are attached by welding, and they can be freely designed.

In addition, each spoke part 12 and the wheel ring 29
If the connection with the wheel ring 29 is also performed by caulking, the welding process can be completely eliminated in the process of attaching the wheel ring 29 to the steering shaft, distortion caused by heat during the welding process is eliminated, and the attachment accuracy is further improved.

Note that the present invention is not limited to this example, and can be implemented in various other ways. for example,
When manufacturing the wheel mounting member 11, the spherical portion 18
Instead of forming a shape 22, as shown in FIG. 5, the bottom surfaces of two truncated cones are connected, and by flattening this shape, the boss plate portion 14 can be made larger as shown in FIGS. 6 and 7. You may also do so.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the main parts of a conventional steering wheel, FIG. 2 is a partially cross-sectional explanatory diagram of the main parts of a steering wheel according to an embodiment of the present invention, and FIGS. An explanatory diagram showing
Figures 4a, b, and c are half-sectional side views of Figures 3d, e, and f, respectively; Figure 5 is an explanatory diagram showing another manufacturing process in Figure 3b; Figures 6 and 7 are respectively FIG. 2 is a half-sectional side view and a plan view of a main part of a wheel mounting member according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 11... Steering wheel, 12... Spoke part, 13... Boss part, 14... Boss plate part.

Claims (1)

[Claims] 1. A boss portion connected to the steering shaft;
A boss plate part that protrudes from the boss part and a spoke part that protrudes from the boss plate part and connects the tip end to the steering wheel ring are integrally constructed as one part by forging process whose wall thickness can be controlled. An automobile steering wheel featuring: