JPH04732B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a steering wheel for an automobile or the like and a method for manufacturing the same.

Prior Art For example, in the steering wheel of an automobile, conventionally, as shown in FIG. 9, a long arc main ring 1 is connected to a short arc sub ring 2 to form an annular wheel ring 6. The wheel ring 6 is placed on the driver's side to weaken the impact force when an accident occurs, and is connected via spokes 4 to a boss plate 3 that connects to a steering shaft (not shown). The above main ring 1, sub ring 2 and spokes 4,
4, as shown in the figure, each end 1a of the main ring 1 is fitted to the bent end 4a of each spoke 4 and welded and connected, and the end 2 of the sub ring 2 is connected to the bent end 4a of each spoke 4.
a, 2a are welded and connected to the bent portions 4b, 4b of the spokes 4, 4, and the other ends 4c, 4c of the spokes 4, 4 are welded and fixed to the boss plate 3. As described above, there have been problems in the past in that the number of parts is large and the installation work is complicated. Also,
Since each member is fixed by welding, the heat generated during welding tends to cause distortion, resulting in poor mounting accuracy and drawbacks. In particular, rings 1 and 2 and spokes 4 and 4 are not on the same plane, and spokes 4 and 4 are not on the same plane.
4 was connected at an angle, which caused the problem that the amount of distortion was likely to be large and the reliability of the mounting strength was low.

Purpose of the Invention The first purpose of the invention is to solve the above problem by integrally molding a boss, a boss plate, a pair of spokes, and a wheel ring to reduce the number of parts and installation work. To provide a steering wheel capable of reducing the number of welding points.

In addition, an object of the second invention is to solve the above-mentioned problem, and by integrally performing plastic working as one part, it is possible to reduce the number of parts, reduce installation work, and improve installation accuracy. The purpose of the present invention is to provide a method for manufacturing a steering wheel that is possible.

Structure, operation, and effects of the invention In order to achieve the above object, the first invention is configured such that the entire steering wheel is integrally plastic-worked. That is, a boss portion connected to the steering shaft, a boss plate portion projecting from the boss portion, a pair of spoke portions projecting from the boss plate portion, and the boss portion extending from the end of the one spoke portion. The wheel ring part is curved in a ring shape around the wheel ring part, and a wheel ring part is provided in the middle part of the wheel ring part to which the other spoke part is fixed.

According to the above configuration, the boss portion, the boss plate portion,
Since the pair of spoke parts and the wheel ring part are integrally constructed, the whole part becomes one part, which greatly reduces the number of parts, and also eliminates the need for attachment work between each member, thereby reducing costs.

In addition, since it can be constructed in one piece by, for example, plastic working, the number of welding points is reduced and the precision of the mutual arrangement between the parts is improved. Since it can be attached to the base, the mounting strength is improved and reliability is increased. In other words, conventionally, bosses, boss plates, and spokes were each attached by welding, which caused distortion due to the heat of welding at each attachment point, while when attaching the spoke end to the wheel ring, the ring and spoke were not on the same plane, making installation difficult. However, according to the first invention, these parts are integrated, eliminating the work of attaching the parts to each other, and since one spoke and the wheel ring can be integrated and placed with high precision, it is easy to attach the other spokes and the wheel ring. Work becomes easier.

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.

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

In order to achieve the above object, the second invention is configured such that a bar to be processed is once punch-rolled to elongate a wheel ring portion, and then plastically worked to integrally manufacture a steering wheel. That is, a step of leaving one end of the rod-shaped workpiece and punching and rolling the other end in the axial direction to form a tubular wheel ring part and stretching it to the other end;
From one end, connect one spoke part, a boss part connected to the steering shaft, a boss plate part that overhangs the boss part and to which the base end of the one spoke part is connected, and a tip protruding from the boss plate part. a step of integrally processing the other spoke portion connected to the tubular wheel ring portion;
bending the pair of spoke portions so that they are open to each other at a predetermined angle with respect to the center of the boss portion;
bending the pair of spokes to form a predetermined angle with respect to the surface of the boss plate;
The tips of one of the spokes are bent, while the tips of the other spoke are bent, the wheel ring section is curved into a ring shape around the boss, and the tips of the one spoke are bent into the wheel ring section. The process of fixing the end of the curved wheel ring part to the bent part of the other spoke part is performed sequentially.

According to the above configuration, the boss portion, the boss plate portion,
A pair of spoke parts and a wheel ring part can be manufactured as a pair by plastic processing from one workpiece material, and the number of parts and installation work can be significantly reduced, resulting in cost reduction, and automation can be easily performed.

In addition, by sequentially performing plastic working, the boss part, the boss plate part, and the pair of spoke parts are integrally molded, while one spoke part and the wheel ring part are integrally molded, so the boss part, the boss plate part, and the pair of spoke parts are integrally molded. This eliminates the need for welding between the wheels and the spokes, improving mounting accuracy and strength, while reducing the number of welds between one spoke and the wheel ring, improving the accuracy of the arrangement of both parts. It can be easily attached to the spoke parts, and overall, steering wheels with less distortion can be manufactured in large quantities and with constant quality. In other words, in the past, the boss and the spokes of the boss plate were manufactured separately and attached to each other by welding, so the heat of welding each member could distort the shape of the boss's mounting hole, for example. On the other hand, when installing spokes and wheel rings, the main ring and sub-ring that make up the wheel ring were welded and fixed to the ends and bends of each spoke, respectively, so the heat of welding caused distortion in both parts, which caused the installation work. It was difficult to perform this accurately. On the other hand, the second book
The invention can solve these problems.

Furthermore, since the workpiece is punch-rolled and the wheel ring portion is stretched, the workpiece may be shorter in size than the product, and the material can be used more effectively.

Furthermore, since it is manufactured by plastic working, the arrangement relationship between the parts can be freely designed.

Therefore, as described above, the second invention can achieve the intended purpose.

Embodiments The present invention will be specifically described below based on illustrated embodiments.

As shown in FIGS. 1 and 2, the steering wheel manufactured by the manufacturing method according to this example has the following features:
For example, it is made of a plastic processed product made of iron, and extends from the boss portion 13 to integrally form the boss plate portion 14, and has a pair of spoke portions 11, 1 that rise at a certain angle from both ends of the upper surface and are open from each other at a certain angle.
2 are integrally formed, while each spoke portion 11,
A wheel ring part 17 is integrally formed at the end of the wheel ring 12.

The boss portion 13 is made of a thick cylindrical body that passes through the center of the boss plate portion 14 and has a through hole 15 in the center thereof, and a serration 19 is formed on the inner peripheral surface of the through hole 15.

The boss plate portion 14 is shaped like a flat plate, and a resin plate 21 is attached to the lower part of the boss plate portion 14 while passing through mounting holes 16, 16 in the vicinity of the boss portion. The portion 14 is integrally molded with resin to form a plate-like portion, and a horn cover 7 (see FIG. 1) or the like is attached to the upper portion of the boss plate portion 14.
Therefore, the connecting portion at the upper end of the steering shaft (not shown) is fitted into the through hole 15 and the serrations 19, and the through holes 16, 16
By fitting screws into the screws to connect and secure the boss plate portion 14 to the upper end of the steering shaft, the shaft and the wheel rotate integrally.

Further, the spokes 11 and 12 are each made of a round rod, and are formed to stand up obliquely upward from the boss plate part 14 at a certain angle in plane symmetry with respect to a plane that bisects the boss plate part 14. One of the spoke parts 12 has its tip 12a bent. The other spoke portion 11 has its tip portion 11a bent and is connected to a tubular wheel ring portion 17.

This wheel ring 17 is curved into a ring shape around the boss portion, its end portion 17a is crushed, and then the bent portion 17 of the other spoke portion 11 is
It is welded to 1b.

An end 12a of one spoke part 12 is attached to the curved inner peripheral surface of the wheel ring part 17 at a position symmetrical to the plane that bisects the boss plate part 14 with respect to the end 11a of the spoke part 11. Weld.

The steering wheel having the above structure is manufactured by plastic working as shown in FIG.

That is, in the first step, a round bar-shaped workpiece 23 made of iron or the like corresponding to the spoke shape shown in FIG. 3a is cut into a predetermined size.

Next, in the second step, as shown in FIG. 3b, one end 23a of the workpiece 23 is left open, and the remaining end 23b is perforated using a piercing mill or the like to form the tubular wheel ring part 17. .

Next, in the third step, an approximately central axial portion of one end portion 23a of the rod-shaped workpiece 23 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, in the fourth step, as shown in FIG. 3c, the workpiece 23 is compressed along the axial direction to form a spherical thick walled part 18 approximately in the center of the heated workpiece 23. Perform upsetting forging.

Next, in the fifth step, as shown in FIGS. 3 d and 4 a, the thick portion 18 heated to approximately 700° C. is formed by die forging on the cylindrical boss portion 13, and a small recess 20 for forming a through hole is formed. , 20 are formed at the center of the upper surface and the center of the lower surface of the boss portion 13, respectively, and the boss plate portion 14 is die-forged into a flat shape around the boss portion 13. Here, one end side of the boss plate part 14 becomes one spoke part 12, and the other end side becomes the other spoke part 11.

Next, in the sixth step, as shown in FIG. 3e and FIG. 4b, the boss plate portion 14 and the boss portion 13 are
The temperature drops to about 300 to 400°C, and after passing through a brittle region of 600°C to remove the distortion caused by the forging, the boss part 13 is extruded downward to the boss plate part 14 to form the boss part 13. At the same time, the small recess 2 formed on the lower surface of the boss portion 13
0 is recessed upward in the axial direction.

Next, in the seventh step, as shown in FIG. 3 f and FIG. While forming serrations 19 on the inner peripheral surface by press working,
A pair of mounting holes 16, 16 are provided through the boss plate portion 14.

Next, in the eighth step, as shown in FIG. 3g, the pair of spoke parts 11 and 12 are placed near the boss plate part 14 together with the wheel ring part 17 in plane symmetry with respect to the plane that bisects the boss plate part 14, and both members are Bending is performed in a dogleg shape so that the gap is opened at a predetermined angle.

Next, in the ninth step, each spoke portion 11 is tilted at a predetermined angle with respect to the surface of the boss plate portion 14, as shown in FIG. 3h and FIG. 5 as a front view thereof. , 12 and the boss plate portion 14 are bent one step to form both spoke portions 11 and 12.

Next, in the 10th step, as shown in FIG. The end portion 11a of the portion 11 is similarly bent into a dogleg shape so as to be approximately parallel to the surface of the boss plate portion, and the wheel ring portion 17 is bent around the boss portion and approximately parallel to the surface of the wheel ring portion. The bent end portions 12a of the spoke portions 12 are curved into a ring shape, and the bent ends 12a of the spoke portions 12 are formed on the inner peripheral surface of the wheel ring 17 and the other spoke portion 11.
Welded to the end portion 11a of the boss plate portion 14 at a position symmetrical to a plane bisecting the boss plate portion 14,
Further, the end portion 17a is subjected to a curved bending process and crushed. And this crushed end 17
a to the bent portion 11b of the other spoke portion 11
Weld to.

The above-mentioned steering wheel is manufactured by sequentially performing the above steps.

According to the steering wheel according to the above embodiment, the boss part 13, the boss plate 14 part, the pair of spoke parts 11 and 12, and the wheel ring part 17 are integrally plastic-processed, so the whole becomes one part, which greatly reduces the number of parts. However, the installation work between each member becomes an expense, and costs can be reduced.

In addition, since it is integrally constructed by plastic working,
The number of welding points is reduced, improving the precision of the arrangement of components, and since the boss portion 13, boss plate portion 14, and pair of spoke portions 11 and 12 are integrally attached, the installation strength is improved and reliability is improved. Sexuality increases.

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, the boss plate portion 14
Since the and spoke parts 11 and 12 can be integrally formed by plastic working, the boss plate part 14 can be made smaller, and the plate 21 to which the horn cover etc. is attached can be made of resin, reducing the overall weight. can be achieved.

Furthermore, since one spoke part 11 and the wheel ring part 17 are integrally molded, the position of the wheel ring part 17 relative to the spoke part 11 can be maintained with high accuracy, and the other spoke part 12 and the wheel ring part 17 can be held in a precise position.
It is easier to install with.

Further, the arrangement relationship between each member is less restricted by welding than by attachment, and can be freely designed.

On the other hand, according to the method for manufacturing a steering wheel, the boss portion 13, the boss plate portion 14, the pair of spoke portions 11 and 12, and the wheel ring portion 17 are plastic-processed from one workpiece to ensure that they are integrated into one piece. The number of parts and installation work can be significantly reduced to reduce costs, and automation can be easily performed.

In addition, by sequentially performing plastic working, the boss portion 13, the boss plate portion 14, and the pair of spoke portions 11 and 12 are integrally molded, and one spoke portion 11 and the wheel ring portion 17 are integrally molded. Therefore, the boss portion 13 and the boss plate portion 14
There is no need for welding between the pair of spoke parts 11 and 12, and the mounting accuracy and mounting strength are improved.
Welding is not required between one spoke part 11 and the wheel ring part 17, which improves the accuracy of the arrangement of both parts, and allows easy attachment to other spoke parts 12, resulting in a steering wheel with less distortion overall. It is possible to reliably manufacture wheels in large quantities and with constant quality.

Furthermore, since the wheel ring portion 17 is stretched by punching and rolling the workpiece, the workpiece may be shorter in size than the product, and the material can be used more effectively.

Furthermore, since it is manufactured by plastic working, the arrangement relationship between the parts can be freely designed.

Also, first, one end 23a of the rod-shaped workpiece 23 is
By locally heating approximately the center to a high temperature, and then using the residual heat without heating again, hot
Since warm forging is performed sequentially, distortion can be removed as the temperature decreases during each forging process.
Boss part 13, boss plate part 14, spoke part 1
The wheel can be manufactured in a state in which the mutual arrangement of the wheels 1, 12 and the wheel ring portion 17 can be maintained with high precision.

Note that the first and second inventions described above are not limited to the respective embodiments described above, and can be implemented in various other forms. For example, in the above wheel, the wheel ring portion 17 may be made of a solid material. Also,
In the boiler manufacturing method described above, a spherical thick-walled portion 1 is provided approximately at the center of one end portion 23a of the rod-shaped workpiece 23.
Instead of upsetting 8, as shown in FIG. 6, the thick portion 22 may have a diamond-shaped cross section with the truncated conical bottom surfaces together. This thick wall portion 22 is forged in the same manner as in the above embodiment, but since the thick wall portion 22 is thicker than the spherical thick wall portion 18 of the above embodiment, the boss plate portion 14 is As shown in FIG. 8, it can be formed wide. Alternatively, instead of welding the bent portion 12a, then crushing the end portion 17a and welding the crushed portion, it is possible to crush the end portion 17a and weld the crushed portion, and then weld the crushed portion. The portion 12a may be welded.
Furthermore, these two welding operations may be performed simultaneously. Further, in FIG. 3c according to the above embodiment, the thick portion 18 may be flattened into a substantially rectangular plate shape, and the boss plate portion may be formed wide as in the above modification.

[Brief explanation of drawings]

1 and 2 are a partially sectional plan view and a partially sectional front view showing a steering wheel according to an embodiment of the present invention, respectively, and FIGS. 3 a to 3 are sequentially showing a steering wheel according to an embodiment of the second invention. Manufacturing process explanatory diagram showing the manufacturing method, Figure 4 a, b, c are respectively Figure 3 d, e, f
5 is a half-sectional front view of FIG. 3h, and FIGS. 6, 7, and 8 are a half-sectional front view of FIG.
FIG. 9 is a plan view of a conventional wheel, and FIG. 9 is a diagram showing a modification of FIG. 11, 12...spoke part, 13...boss part,
14...Boss plate part, 17...Wheel ring part, 18...Thick wall part, 23...Work material.

Claims (1)

[Claims] 1. A boss portion connected to a steering shaft;
a boss plate portion projecting from the boss portion; a pair of spoke portions projecting from the boss plate portion; extending from an end of the one spoke portion and curved in a ring shape around the boss portion; A steering wheel characterized in that the steering wheel is provided with a wheel ring part having the other spoke part fixed to the middle part thereof. 2 A step of leaving one end of the rod-shaped workpiece and punching and rolling the other end in the axial direction to form a tubular wheel ring part while extending it to the other end; a boss portion connected to the steering shaft; a boss plate portion overhanging the boss portion and connected to the base end of the one spoke portion; and a boss plate portion protruding from the boss plate portion and having a tip connected to the tubular wheel ring portion. a step of integrally processing the spoke portions with the other spoke portion; a step of bending the pair of spoke portions so that they are mutually open at a predetermined angle with respect to the center of the boss portion; a step of processing the pair of spoke portions into the boss plate portion; A step of bending the wheel ring part to form a predetermined angle with respect to the plate surface; bending the tip of one of the spoke parts, bending the tip of the other spoke part, and forming the wheel ring part into a ring shape around the boss part; The following steps are sequentially performed: bending the wheels, fixing the tip of one spoke part to the wheel ring part, and fixing the end of the curved wheel ring part to the bent part of the other spoke part. A method of manufacturing a steering wheel.