JP3275843B2 - Steering wheel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a steering wheel.

[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]

By the way, in the field of the steering wheel, it is generally practiced to reduce the weight as a whole by forming the spoke core and the like from die-cast aluminum. In this case, it is necessary to connect the aluminum spoke core to the iron boss. Here, in the case of a normal boss (having a substantially cylindrical shape), a preformed boss is set as an insert in a die casting mold, and in that state, molten aluminum is poured. Then, the spoke core is connected to the periphery (edge) of the boss, that is, the edge of the boss is embedded in aluminum so that the core is formed.

However, when the above-mentioned yoke type boss is employed, such technology cannot be applied as it is. This is because the yoke portion of the yoke-type boss has a substantially C-shape in a plane, and molten aluminum flows around from the opening.

[0010]

According to the first aspect of the present invention, a tubular member is fitted into a steering shaft having a serration having a plurality of teeth on its outer periphery, and is provided integrally with the tubular member. A boss having a serration corresponding to the serration on the inner periphery, a yoke portion having a female hole formed on at least one of the bolt holes and having a bolt hole formed at a substantially end thereof, A steering wheel body having a ring core and a spoke core, and a part of the spoke core is connected to the boss, and a bolt having a male screw at least at a substantially end is screwed into the bolt hole. By wearing
A steering wheel for fixing a connected boss of the steering wheel body to the steering shaft, the boss being a plate-shaped boss plate and a steel plate fixedly welded to an inner periphery of a through hole in a central portion of the plate. And a boss body composed of a cylindrical portion and a yoke portion formed in a substantially C-shape in a plane at an upper portion thereof.

Further, in the invention according to claim 2,
2. The steering wheel according to claim 1, wherein the boss plate is formed such that an inner periphery of the through hole at the central portion extends downward and protrudes, and the cylindrical portion is an inner periphery of the extending and protruding through hole. The gist of the invention is that it is fixed by welding to the boss plate at the edge of the boss plate.

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 a vehicle.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG.
FIG. 1 is a cross-sectional view taken along line AA of FIG. 3 and FIG. 2 is a cross-sectional view taken along line BB of FIG. 3.

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. Further, the ring portion 2 is constituted by a ring portion core metal 5 made of, for example, a steel pipe and a coating 7a covering the ring portion core, and the spoke portion 4 is made of a spoke portion core metal 6A, 6B, 6C made of die-cast aluminum. Coating body 7 to be coated
b. The covering members 7a and 7b and the pad portion 3 are made of a soft synthetic resin material (for example, polyurethane foam).
Are formed integrally. 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 a 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 an inflating 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, more specifically, with the spoke cores 6A to 6C. That is, as shown in FIG. 6, the boss 8 is connected to the spoke cores 6 </ b> B and 6 </ b> C on the left and right sides via the connecting portion 21. However, the boss 8 includes the ring core 5 and the spoke cores 6B, 6B.
It is located below C.

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 the present embodiment, the boss 8 is made of steel, and the connecting portion 21, the sub-connecting portion 22, and the support bar 24 are made of die-cast aluminum similarly to the spoke portion core metal 21.

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 will be described.

As shown in FIGS. 1 and 2, a predetermined number (generally, about 30
Serrations 31 having teeth 31a are formed,
An annular groove 32 as a constricted portion is provided at a central portion in the vertical direction.
Are formed. The boss 8 is formed in a plate-shaped 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 thereof. Boss body 3 composed of yoke 35
6 is provided. At the substantially leading end of the C-shaped yoke portion 35, bolt holes 37 having different inner diameters are provided.
A, 37B are formed. A female screw is formed in the small-diameter bolt hole 37A. Further, the steering shaft 30 is provided on the inner peripheral surface of the cylindrical portion 34.
Serration 38 corresponding to serration 31 of FIG.
Reference) is formed. A cylindrical portion 34 is fitted at the tip of the steering shaft 30 so that the serrations 31 and 38 mesh with each other. Further, as shown in FIG. 4, a bolt 41 is inserted through the bolt holes 37A and 37B, and especially, a small-diameter bolt hole 37A.
Screwed against

On the other hand, a part of the edge of the boss plate 33 is buried in the spoke cores 6A to 6C. By this embedding, the boss 8 and the spoke portion core metal 6A ~
6C is connected.

Next, a procedure until the steering wheel W is mounted on the steering shaft 30 will be described.
First, as shown in FIG. 5, the boss body 36 (the tubular portion 34)
Is fitted into the through hole of the boss plate 33 and welded.
Thereby, the boss 8 is formed. Further, a ring core metal 5 is separately formed.

Subsequently, the boss 8 and the ring core 5 thus obtained are set in a mold (not shown). At this time, a cavity for forming the spoke cores 6A to 6C (including the connecting part 21, the sub-connecting part 22, the support bar 24, and the like) is formed. Thereby, it is isolated from the yoke portion 35. Then, molten aluminum is poured into the cavity. Then, aluminum is filled in the cavity. At this time, the boss plate 33
, The aluminum in the molten state does not go around the yoke portion 35 in the mold. For this reason, as shown in FIG. 6, die-cast aluminum is formed so that the edge of the boss plate 33 is buried.
Spoke core metals 6A to 6C are obtained.

Thereafter, 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. Then, 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 FIGS. 1 and 2, the boss 8 (the tubular portion 34) with which the steering wheel body 1 is integrated is inserted into the tip of the steering shaft 30. At this time, the serrations 31 of the steering shaft 30
And serrations 38 formed in the cylindrical portion 34 of the boss 8
Is inserted so as to engage.

In this state, the bolt 41 is inserted into the bolt holes 37A and 37B of the yoke portion 35, and the male screw of the bolt 41 is screwed into the bolt hole 37A in which the female screw is formed. By this screwing, the serrations 31 and 38 are further meshed with each other (the serrations 31 and 38 abut on each other), and the yoke 35 is tightened. The movement in the direction is regulated. Further, 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 pad 3 is covered with the cover 7 by using the yoke type boss 8.
a, steering wheel W integrally formed with 7b
Even so, attachment to the steering shaft 30 can be performed relatively easily.

(B) In the present embodiment, the boss 8
A boss body 36 composed of a cylindrical portion 34 and a yoke portion 35
On the other hand, the boss plate 33 having a larger area than the yoke portion 35 is fixed by welding. When the spoke cores 6A to 6C are to be cast from aluminum, the boss plate 33 plays a role of a seal in the mold, and the molten aluminum is used for the yoke 3.
The boss 8 (the tubular portion 34) does not go into the inside of the boss 8 from the opening portion 5. For this reason, the end portion of the boss plate 33 is embedded in the die-cast aluminum spoke cores 6A to 6C obtained by casting. Can be obtained reliably.

(C) Further, as a matter of course, the spoke cores 6A to 6C can be made of die-cast aluminum, so that the overall weight can be reduced.

(D) In addition, in the present embodiment, the serrations 31 and 38 are further meshed with each other (the serrations 31 and 38 abut on each other) and the yoke portion 35 is The steering shaft 3 of the steering wheel W is to be tightened.
The movement in the rotation direction with respect to 0 can be restricted.
In addition, the bolt 41 is fitted into the annular groove 32 of the steering shaft 30, so that the vertical movement of the boss 8 and thus the steering wheel W can be restricted. Therefore, the steering wheel W can be firmly fixed to the steering shaft 30.

The present invention can be embodied as follows in addition to the above embodiment. (1) In the above embodiment, the steering wheel W is embodied as a type having three spokes 4 (spoke cores 6A to 6C), but four or more or two spoke cores are used. It can also be embodied as having.

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

(3) In the above-described embodiment, the annular groove 32 is provided on the entire periphery of the steering shaft 30 as the constricted portion. However, the constriction may be partially provided instead of the entire periphery. Further, a configuration in which the constricted portion is omitted may be adopted.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line AA of FIG. 3 showing a steering wheel according to an embodiment.

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

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

FIG. 4 is a partial plan view showing a yoke part and the like.

FIG. 5 is a divided perspective view showing an operation when connecting the boss body and the boss plate.

FIG. 6 is a perspective view showing a cored bar, a boss, and the like.

[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 portion, 34: cylindrical portion, 35: yoke portion, 37
A, 37B: bolt hole, 38: serration, 41: bolt, W: steering wheel.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-9-226600 (JP, A) JP-A-5-116581 (JP, A) JP-A-2-133955 (JP, U) JP-A-62-1 125667 (JP, U) Japanese Utility Model Showa 58-153162 (JP, U) Japanese Utility Model Showa 60-158963 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B62D 1/04-1 / 28

Claims (2)

(57) [Claims] 1. A steering shaft (30) having a serration (31) comprising a plurality of teeth (31a) on an outer periphery.
And the cylindrical portion (34) and the cylindrical portion (3
4), and a bolt hole (37)
A, 37B) is formed, and at least one of the bolt holes (37A, 37B) (37A) is provided with a yoke portion (35) formed with a female screw, and the inner periphery corresponds to the serration (31). Serrations (3
8), a boss (8) having a ring core (5) and a spoke core (6A, 6B, 6C), and one of the spoke cores (6A, 6B, 6C). A steering wheel main body (1) connected to the boss (8), and a bolt (41) having a male thread at least substantially at a tip is screwed into the bolt hole (37A, 37B). The connected boss (8) of the steering wheel body (1) is connected to the steering shaft (3).
A steering wheel to be fixed to the boss (8), wherein the boss (8) is fixed to a plate-shaped boss plate (33) and a steel cylinder welded and fixed to an inner periphery of a through hole at a central portion of the plate (33). (34) and the upper surface thereof have a substantially C plane.
A boss body (36) comprising a yoke portion (35) formed in a character shape. 2. The boss plate (33) is formed such that an inner periphery of the through hole at the central portion extends downward and protrudes, and the cylindrical portion (34) is formed by extending the through hole and protrudes therethrough. The steering wheel according to claim 1, wherein the inner peripheral edge is welded and fixed to the boss plate (33).