JP3209076B2 - Steering wheel mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering wheel mounting structure.

[0002]

2. Description of the Related Art A steering wheel has an annular ring portion, a pad portion provided at the center of the ring portion, and a spoke portion extending from the ring portion. At the same time, the spoke core is embedded in the spoke. In this case, the ring core metal and the spoke core metal are covered with a covering made of, for example, foamed polyurethane. Further, below the pad portion, a tip portion of the spoke core is connected to a boss plate (boss). The boss has a serration on the inner periphery of the insertion hole, is fitted to the tip of a steering shaft having the same serration, and is then attached by tightening a nut.

[0003] In the steering wheel constructed as described above, the spoke core and the boss integrated with the steering wheel body are attached to the steering shaft by nut tightening. It is mounted, and the pad portion is mounted thereon.

On the other hand, in recent years, there has been proposed a steering wheel in which the cover and the pad portion are integrally formed to eliminate the boundary between the cover and the pad portion (for example, Japanese Unexamined Utility Model Application Publication No. 2-133955). No.). According to this technique, the cover and the pad portion are integrated, and the design can be improved.

[0005] However, in the above technique, it is very difficult to insert the steering wheel body into the tip of the steering shaft and then tighten the nut with a nut. This is because the upper portion of the steering wheel body is not open because the pad portion is integrated with the cover.

On the other hand, it is conceivable to employ a yoke type boss and fasten the steering wheel with bolts from the lateral direction. That is, the yoke type boss includes a cylindrical portion having serrations corresponding to the serrations of the steering shaft on the inner periphery, and a yoke portion provided integrally with the cylindrical portion. The yoke has a substantially C-shape in plan view, and a bolt hole is formed at a substantially distal end. A female screw is formed in at least one of the bolt holes. On the other hand, a constricted portion is formed at a position corresponding to the bolt hole on a part of the steering shaft.

[0007] By screwing a bolt into the bolt hole, the serrations mesh with each other and the yoke portion is tightened. Therefore, the movement of the steering wheel in the turning direction is restricted. At the same time, the shaft of the bolt is fitted into the constricted portion. Therefore, the vertical movement of the steering wheel is also restricted. Therefore, according to this technique, it is possible to relatively easily perform the mounting operation even on a steering wheel in which the pad portion is integrated with the cover.

[0008]

However, in the above-mentioned prior art, the shaft portion of the bolt connecting the steering wheel and the steering shaft is directly fitted into the narrow portion of the steering shaft. For this reason, when an external stress is applied to the steering wheel, stress distortion between the steering wheel and the steering shaft is directly transmitted to the bolt. As a result, after the steering wheel is assembled, there is a possibility that the fastening portion of the bolt is loosened or the screw portion (male screw or female screw) is damaged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a steering wheel in which a cover for covering a ring core and a spoke core and a pad are integrally formed. It is another object of the present invention to provide a steering wheel mounting structure capable of improving workability at the time of assembling and securing stability of a mounting state.

[0010]

In order to achieve the above object, according to the first aspect of the present invention, an inner portion is fitted into a steering shaft having a serration having a plurality of teeth on an outer periphery and having a constricted portion, and an inner portion thereof. A cylindrical part having a serration corresponding to the serration on the circumference,
A boss provided integrally with the cylindrical portion, having a yoke portion having a bolt hole formed at a substantially end thereof and a female screw formed in at least one of the bolt holes; A spoke portion core bar, a cover for covering these core bars, and a pad portion substantially at the upper center of the ring portion, and a pad portion integrally formed with the cover member, and a part of the spoke portion core bar is A steering wheel with a steering wheel body connected to the
The bolt holes, by screwing the bolt having a male thread at least substantially tip, a mounting structure of a steering wheel for fixing the steering wheel to the steering shaft, the outer periphery of the front Symbol bolt, cylindrical collar And the collar is attached to the bolt.
The gist is that the steering shaft is fitted into the constricted portion of the steering shaft in the insertion direction .

According to the invention described in claim 2, in the mounting structure for a steering wheel according to claim 1,
The gist is that the collar is immovably provided between the male screw of the bolt and an enlarged portion provided on a part of the shaft.

Further, according to the third aspect of the present invention, in the steering wheel mounting structure according to the first or second aspect, the collar is made of a material having a strength equal to or higher than that of the bolt and the boss. The gist is that it has been done.

According to a fourth aspect of the present invention, in the steering wheel mounting structure according to any one of the first to third aspects, the bolt is provided with the enlarged diameter portion so as to facilitate a screwing operation. The gist of the present invention is to have an extension shaft between the head and the head.

Note that the vertical direction of the steering wheel in the present description refers to the direction along the axial direction of the steering shaft, and does not necessarily mean the vertical direction when the steering wheel is mounted on the vehicle.

(Operation) According to the first aspect of the present invention, the boss portion connected to the steering wheel main body is provided on the steering shaft having the serration composed of a plurality of teeth on the outer periphery and having a constricted portion. The serrations on the inner periphery of the cylindrical portion are fitted so as to mesh with the serrations. Then, the bolt is screwed into the bolt hole of the yoke portion. By this screwing, the serrations are further engaged with each other, and the yoke portion is tightened, so that the movement of the steering wheel in the rotation direction with respect to the steering shaft is restricted. Also,
Basically, the vertical movement is restricted by inserting a bolt through the constricted portion of the steering shaft.
Due to these restrictions, the steering wheel is fixed to the steering shaft.

In the present invention, a cylindrical collar is provided on the outer periphery of the bolt, and the collar is fitted into the constricted portion of the steering shaft. For this reason, even if an external stress is applied to the steering wheel and a distortion stress occurs between the steering wheel and the steering shaft, the stress is first transmitted to the collar. For this reason, problems caused by the direct transmission of the strain stress to the bolt are avoided.

According to a second aspect of the present invention, in addition to the operation of the first aspect, the collar is provided with a male screw of the bolt and an enlarged portion provided on a part of a shaft portion. It is provided immovably between the diameter part. For this reason, there is no play between the collar and the bolt, and the mounting state is further stabilized.

Further, according to the third aspect of the present invention,
In addition to the effects of the invention described in claims 1 and 2, the collar is made of a material having a strength equal to or higher than that of the bolt and the boss. For this reason, it becomes difficult for the collar itself to be deformed or damaged by the strain stress.

In addition, according to the invention described in claim 4,
In addition to the effects of the invention described in claims 1 to 3, the bolt has an extension shaft portion between the enlarged diameter portion and the head. Therefore, the bolt becomes relatively long, and the screwing operation can be easily performed.

[0020]

Thus, according to the present invention, in a steering wheel in which a pad covering a ring core metal and a spoke core metal and a pad portion are integrally formed, workability in assembling is improved. And an excellent effect that the stability of the mounting state can be ensured.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 3 is a rear view of the steering wheel W according to the present embodiment, and FIG. 2 is a cross-sectional view taken along line AA of FIG.

As shown in these figures, a steering wheel main body 1 of a steering wheel W includes an annular ring portion 2 and a pad portion 3 disposed at the center of the ring portion 2.
And three spoke portions 4 extending from the ring portion 2. The ring portion 2 is composed of a ring core 5 made of, for example, a steel pipe and a covering 7a that covers the ring core. The spoke portion 4 is made of a spoke core 6A made of a lightweight die-cast metal such as an aluminum alloy. 6B and 6C and a covering 7b for covering them.
The covering members 7a and 7b and the pad portion 3 are integrally formed of a soft synthetic resin material (for example, polyurethane foam). The steering wheel main body 1 is fixedly attached to the boss 8. This assembly structure will be described later in detail.

On the other hand, a storage recess 11 surrounded by the cover 7b is formed below the pad portion 3. The storage recess 11 is provided with a membrane switch (not shown) and an airbag device 13. The membrane switch has upper and lower thin plates that form part of a horn switch circuit (not shown), and the thin plates contact each other when the pad unit 3 is pressed, and the horn sounds in accordance with the contact.

The airbag device 13 is a bag-shaped airbag 14 which is folded and stored, an inflator 15 for supplying inflation gas to the airbag 14, and holds and fixes the airbag 14 and the inflator 15. And a bag holder 16. The bag holder 16 is
For example, as shown in FIG. 2, the spoke portion is fixed to the core metal 6 </ b> A and the like by screws 17.

The boss 8 is formed integrally with the steering wheel body 1. That is, the boss 8
Are connected to the spoke cores 6 on the left and right sides via the connecting portion 21.
B, 6C. However, the boss 8 is located below the ring core 5 and the spoke cores 6B and 6C.

Also, the spoke cores 6B, 6C
For the remaining spoke driver core 6A (on the driver's side)
They are connected by the sub-connecting part 22. by this,
The spoke cores 6A to 6C, the ring core 5 and the boss 8 are firmly connected to each other, and the boss 8, the connecting portion 21 and the sub-connecting portion 22 make a comparison on the driver's seat side of the boss 8. The target opening 23 is formed.
Further, each spoke portion core metal 6B, 6C is connected to the support bar 2
4 (see FIG. 2), and the airbag 1
4 The stability at the time of widening is ensured.

In this embodiment, a lower cover (not shown) made of resin is provided so as to surround the lower side of the steering wheel body 1. Next, details of the mounting structure of the steering wheel W (characteristic part of the present embodiment) will be described.

As shown in FIGS. 1, 2, 5, and 7, a predetermined number (generally,
A serration 31 having approximately 30 teeth 31a is formed, and an annular groove 32 as a constricted portion is formed in a central portion in the vertical direction. The boss 8 has a plate-like boss plate 33, a steel tubular portion 34 welded and fixed to the inner periphery of the through hole at the center of the plate 33, and a substantially C-shaped plane at the upper portion. And a yoke portion 35. Bolt holes 36 and 37 having different inner diameters are formed at substantially the front end of the C-shaped yoke portion 35. A female screw is formed in the small-diameter bolt hole 36. Further, serrations 31 of the steering shaft 30 are provided on the inner peripheral surface of the cylindrical portion 34.
Are formed. A cylindrical portion 34 is fitted into the tip of the steering shaft 30 so that the serrations 31 and 38 mesh with each other. Further, a bolt 41 is inserted through the bolt holes 36 and 37, and is screwed into the small-diameter bolt hole 38 in particular.

More specifically, as shown in FIG. 6, the bolt 41 has a shaft portion 42 and a head portion 43, and a male screw is formed on one side of the shaft portion 42. The shaft portion 42 includes a general shaft portion 44 and an extended shaft portion 45 located on the male screw side, and an enlarged diameter portion 46 is integrally formed between the shaft portion 42 and the extended shaft portion 45.

In this embodiment, the general shaft 4
4 between the male screw and the enlarged diameter portion 46.
Similarly, a cylindrical collar 47 made of steel is fitted around. Further, a washer 48 is interposed between the collar 47 and the enlarged diameter portion 46. For this reason, the collar 47 is provided between the enlarged diameter portion 46 (the washer 48) and the male screw.
It is in a state where it cannot be moved.

In the present embodiment, as shown in FIG. 1, not the general shaft portion 44 of the bolt 41 but the collar 47
Are fitted in the annular groove 32 of the steering shaft 30. Thus, the boss 8 is firmly fixed to the tip of the steering shaft 30 by the bolt 41, and as a result, the steering wheel W is attached to the steering shaft 30.

Next, a procedure for attaching the steering wheel W to the steering shaft 30 will be described. First,
As shown in FIG. 4, the membrane switch and the airbag device 13 are inserted through the opening 23 formed by the boss 8, the connecting portion 21, and the sub-connecting portion 22. And
The bag holder 16 of the airbag device 13 is fixed to the spoke portion core metal 6A and the like by screws 17. At this time, since the opening 23 is formed relatively large, the airbag device 13 can be easily mounted inside the steering wheel body 1.

Next, as shown in FIG. 5, a boss 8 with which the steering wheel body 1 is integrated is inserted into the tip of the steering shaft 30. At this time, the serration 31 of the steering shaft 30 and the serration 38 formed on the cylindrical portion 34 of the boss 8 are inserted so as to mesh with each other.

Then, as shown in FIG. 8, a bolt 41 integrated with the collar 47 is inserted through the bolt holes 37 and 36 of the yoke 35 in this state.
The male screw of the bolt 41 is screwed into the bolt hole 36 in which the female screw is formed. By this screwing, as shown in FIGS. 1 and 9, the serrations 31 and 38 are further engaged with each other (the serrations 31 and 38 abut on each other), and the yoke 35 is tightened. Steering shaft 3 of steering wheel W
The movement in the rotation direction with respect to 0 is restricted. Further, the collar 47 on the outer periphery of the bolt 41 is inserted (fitted) into the annular groove 32 of the steering shaft 30, and
The vertical movement of the boss 8 and thus the steering wheel W is restricted. Due to these restrictions, the steering wheel W is fixed to the steering shaft 30.

Next, the operation and effect of this embodiment will be described. (A) As described above, in the present embodiment, the bolt 41
A cylindrical collar 47 is provided on the outer periphery of the steering shaft 30, and the collar 47 is fitted into the annular groove 32 of the steering shaft 30. For this reason, after assembling, an external stress is applied to the steering wheel W, and a distortion stress may be generated between the steering wheel W and the steering shaft 30. Even in such a case, the stress is first applied to the collar 47. Is transmitted. Therefore, the strain stress is not directly transmitted to the bolt 41. Therefore, it is possible to prevent the fastening portion of the bolt 41 from being loosened and the screw portion (male screw or female screw) from being damaged.

(B) According to the present embodiment, the collar 47 is immovably provided between the male screw of the bolt 41 and the enlarged diameter portion 46 (the washer 48). Therefore, there is no play between the collar 47 and the bolt 41, and the mounting state can be further stabilized.

(C) Further, the collar 47 is made of the same material as the bolt 41. Therefore,
The collar 47 itself is less likely to be deformed or damaged by the strain stress.

(D) In addition, according to the present embodiment, the overall length of the bolt 41 is increased by providing the extension shaft 45 to the bolt 41. Therefore, the screwing operation of the bolt 41 from the lateral direction of the steering wheel W can be easily performed. As a result, the workability at the time of attachment can be improved.

The present invention can be embodied as follows in addition to the above embodiment. (1) In the above-described embodiment, the collar 47 is configured to be inserted only into the large-diameter bolt hole 37. However, the collar 47 may be further elongated so as to be partially inserted into another bolt hole 36. Is also good. However, in this case, it is necessary to secure a sufficient screw allowance by providing a projection or the like.

(2) In the above embodiment, the steering wheel W is embodied as a type having three spokes 4 (spoke cores 6A to 6C). However, four or more or two spokes 4 are provided. The present invention can be embodied as having a cored bar.

(3) In the above embodiment, the steering wheel W having the airbag device 13 has been embodied. However, instead of the airbag device 13, a steering wheel having a shock absorbing member may be embodied. it can.

(4) Washer 4 in the above embodiment
8 may be omitted. Also, the extension shaft 45,
The configuration may be such that the enlarged diameter portion 46 and the like are omitted. (5) In the above embodiment, the annular groove 32 is provided on the entire circumference of the steering shaft 30 as the constricted portion. However, the constriction may be partially provided instead of the entire circumference.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing a mounting structure of a steering wheel according to an embodiment.

FIG. 2 is a sectional view taken along line AA of FIG. 3;

FIG. 3 is a rear view of the steering wheel.

FIG. 4 is a sectional view of a steering wheel body and the like showing a state when an airbag device and the like are arranged.

FIG. 5 is a cross-sectional view illustrating an operation when the steering wheel is mounted on the steering shaft.

FIG. 6 is a sectional view showing bolts and the like.

FIG. 7 is a longitudinal sectional view showing a configuration of a boss and the like.

FIG. 8 is a cross-sectional view of a boss and the like showing a state at the time of bolt screwing.

FIG. 9 is a vertical sectional view of a main part showing a mounting structure of the steering wheel.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Steering wheel main body, 2 ... Ring part, 3 ... Pad part, 5 ... Ring part core metal, 6A, 6B, 6C ... Spoke part core metal, 7a, 7b ... Coating body, 8 ... Boss, 30 ... Steering shaft, 31 ... serration, 32 ... annular groove as constricted part, 34 ... cylindrical part, 35 ... yoke part, 3
6, 37 ... bolt hole, 38 ... serration, 41 ... bolt, 42 ... shaft, 43 ... head, 45 ... extension shaft, 46 ...
Enlarged part, 47 ... color, W ... steering wheel.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-9-164959 (JP, A) JP-A-8-119119 (JP, A) JP-A-2-133973 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B62D 1/04-1/28

Claims (4)

(57) [Claims] 1. A steering shaft (30) having a serration (31) comprising a plurality of teeth (31a) on an outer periphery thereof and having a constricted portion (32),
A cylindrical portion (34) having a serration (38) corresponding to the serration (31) is provided on the inner periphery, and is provided integrally with the cylindrical portion (34).
6, 37) and a boss (8) having a yoke (35) formed with a female screw in at least one of the bolt holes (36), a ring core (5), and spokes. Core metal (6A, 6B, 6
C) and the coverings (7a, 7b) covering the metal cores (5, 6A, 6B, 6C) and the ring part (2), and are integrally formed on the coverings (7a, 7b). Pad portion (3), and the spoke portion core metal (6)
A, 6B, 6C) in a steering wheel (W) including a steering wheel body (1) connected to the boss (8).
7), a bolt (4
1) is a mounting structure of a steering wheel for fixing the steering wheel (W) to the steering shaft (30) by screwing the collar (41) on the outer periphery of the bolt (41). ), And the collar (47) is attached to the bolt (4 ).
A mounting structure for a steering wheel, characterized in that it is fitted into the constricted portion (32) of the steering shaft (30 ) in the insertion direction of 1) . 2. The collar (47) is connected to the bolt (4).
2. The steering wheel mounting according to claim 1, wherein the steering wheel is mounted so as not to be movable between the male screw of (1) and an enlarged diameter portion (46) provided on a part of the shaft portion (42). Construction. 3. The bolt (4) is provided with the collar (47).
The mounting structure for a steering wheel according to claim 1 or 2, wherein the mounting structure is made of a material having strength equal to or higher than 1) and the boss (8). 4. The bolt (41) has an extension shaft (45) between the enlarged diameter portion (46) and the head (43) to facilitate a screwing operation. The mounting structure for a steering wheel according to claim 1.