JP2648547B2 - Steering wheel - 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 having a boss integrally formed by forging.

[0002]

2. Description of the Related Art Conventionally, a steering wheel described in, for example, Japanese Patent Publication No. 2-47047 is known.
As shown in FIG. 13, the steering wheel is configured such that a steering wheel main body 1 is rotatably supported on a vehicle body 3 via a steering shaft 2.

[0003] The steering wheel body 1 is
It has an annular rim 1a, a boss 1b located at the center of the rim 1a, and a spoke 1c connecting the rim 1a and the boss 1b. The steering shaft 2 is fitted, and positioning holes (cancel pin holes) 1d are formed at a plurality of locations on the lower surface of the boss 1b.

[0004] A rotation direction indicator switch 4 is provided between the steering wheel body 1 and the vehicle body 3.
The rotation direction indicator switch 4 includes a cancel cam 5 that rotates together with the steering wheel body 1,
An operation member 6 provided to be rotatable by a predetermined angle with respect to
It comprises a stopper 7 fixed to the vehicle body 3 and the like.

The cancel cam 5 has a substantially cylindrical shape to be inserted into the steering shaft 2, and has a positioning projection (cancel pin) 5a that fits into each of the positioning holes 1d of the boss 1b. At the same time, a canceling projection 5b protrudes from the peripheral surface, and is integrally rotated with the steering wheel body 1 by engagement of each positioning hole 1d with the positioning projection 5a.

The operation member 6 includes a bracket 6a having a substantially U-shape in a plane surrounding the cancel cam 5, and a bracket 6a
An operation lever 6b fixed to the bracket 6a, and a ratchet 6c elastically supported between the distal ends of the bracket 6a, from which an elastic engaging portion 6d protrudes elastically can reciprocate. Have been.

Further, the stopper 7 is formed in a substantially arc-shaped plate centering on the steering shaft 2, and has a left-rotation position concave portion in which the elastic engaging portion 6d of the ratchet 6c selectively engages. A position recess and a right rotation position recess are sequentially formed.

In the rotation direction indicator switch 4, the elastic engagement portion 6d of the ratchet 6c is normally held at the neutral position while being engaged with the neutral position recess of the stopper 7. Further, for example, when the operation lever 6b is rotated clockwise, the elastic engaging portion 6d of the ratchet 6c is engaged and held in the right rotation position recess of the stopper 7, and a switch for instructing right rotation is connected. . Further, in a state where the operation lever 6b is rotated in the counterclockwise direction, the elastic engagement portion 6d of the ratchet 6c is engaged and held in the left rotation position concave portion of the stopper 7,
A switch for instructing left rotation is connected.

In a state in which the steering wheel body 1 is rotated and then returned in the opposite direction, the canceling projection 5b of the cancel cam 5 rotating together with the steering wheel body 1 comes into contact with the ratchet 6c. The engagement between the elastic engaging portion 6d of 6c and the left rotation position concave portion or the right rotation position concave portion of the stopper 7 is released, and the operation lever 6b automatically returns to the neutral position.

In the conventional steering wheel configuration, the boss portion of the steering wheel body 1 is used to reduce the size of the boss portion 1b of the steering wheel.
1b, a metal boss plate is provided, a metal boss to which the steering shaft 2 is fitted is fixed to the boss plate, and a plurality of positioning holes 1d are integrally formed in the boss. I have.

The positioning holes 1d are formed by drilling.

[0012]

However, in the above-mentioned conventional structure, the operation of forming the positioning hole 1d by drilling the boss is complicated. In particular, when the position of the positioning hole 1d is increased, the number of work steps increases. Therefore, there is a problem that the manufacturing process becomes complicated.

The present invention has been made in view of the above points, and has as its object to provide a steering wheel having a boss which is easy to manufacture and has high accuracy.

[0014]

According to a first aspect of the present invention, there is provided a steering wheel having a metal boss fixed to a steering shaft rotatably supported by a vehicle body, to which a rotation direction indicator switch is connected. In a steering wheel including a steering wheel body, the boss includes a fixed portion fixed to a steering shaft, and a positioning protrusion provided on the rotation direction indicator switch and protruding from a rotating member that rotates with the steering wheel body. The positioning recess to be fitted is integrally formed by forging
Together have been made, the positioning recess, the stearate
The direction toward the coupling shaft is closed, and an opening is formed from the direction toward the vehicle body to the radially outward direction of the steering shaft.

[0015] The steering wheel according to claim 2 is
A steering wheel including a steering wheel body having a metal boss fixed to a steering shaft rotatably supported on a vehicle body and connected to a rotation direction indicator switch, wherein the boss is a steering wheel.
A fixing portion fixed to the shaft, an end surface portion having a smooth flat surface portion facing the vehicle body, and provided at a plurality of positions on the end surface portion, and opening at least in a direction toward the vehicle body, the rotation direction indicator switch A positioning concave portion provided with a positioning protrusion protruded from a rotating member that rotates together with the steering wheel body, and an adjusting concave portion provided between these positioning concave portions are integrally formed by forging.
It was a thing.

[0016]

In the steering wheel according to the first aspect, the boss for fixing the steering wheel body and the steering shaft is easily manufactured by forging. By fitting the positioning protrusion projected from the rotating member provided on the rotation direction indicator switch to the positioning recess of the boss,
The rotating member is positioned and rotates with the steering wheel body. The positioning recess, by forging, stearyl
Since it is formed integrally with the boss having a fixing portion fixed to the ringing shaft, a complicated operation of forming a positioning recess by drilling or the like on the boss is unnecessary. The boss positioning recess is closed in the direction toward the steering shaft.
As well as being closed , the opening is formed from the direction toward the vehicle body to the outside in the radial direction of the steering shaft, so that the deformation of the positioning recess in the forging process is suppressed, the dimensional accuracy of the boss is increased , and the steerin
The generation of burrs toward the shaft is suppressed.

In the steering wheel according to the second aspect, the boss for fixing the steering wheel body and the steering shaft is easily manufactured by forging. The rotating member is positioned and rotated together with the steering wheel main body by fitting a positioning projection provided from a rotating member provided on the rotation direction indicator switch into a positioning recess provided on the end surface of the boss. The positioning recess is fixed to the steering shaft by forging.
Since it is formed integrally with the boss having the fixed portion, a complicated operation of forming the positioning recess by drilling or the like on the boss is not required. Since the boss is formed with a smooth flat surface at the end face toward the vehicle body, the electrode for resistance welding is in close contact with the flat surface, and the current value of resistance welding is stabilized. Since the adjusting recesses are provided between the positioning recesses provided at a plurality of positions on the end face portion, in the boss forging process, the variation in the volume of the material is adjusted by the depth dimension of the adjusting recesses. The accuracy of the part is increased.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a steering wheel according to an embodiment of the present invention.

In FIG. 2, reference numeral 11 denotes a steering wheel main body. The steering wheel main body 11 has an annular rim portion 12, a boss portion 14 located at the center thereof, and the rim portion 12 and the boss portion 14 connected to each other. It is composed of a plurality of spoke parts 15. The periphery of the rim portion 12 and the spoke portion 15 is covered with a covering material 17 made of a soft synthetic resin, and the upper side (occupant side) of the boss portion 14 is
It is covered with a cover 18 made of synthetic resin.

As shown in FIG. 1, a metal boss 21 fitted to a steering shaft 20 is provided below the boss portion 14 (on the vehicle body side). A boss plate 22 is fixed to the located upper surface portion 21a by resistance welding.

The boss 21 is connected to the boss 21 shown in FIGS.
As shown in the illustration, the fixed steering shaft 20 fits
It has a substantially cylindrical shape in which a fitting hole 24 as a part is formed in an axial center part, and is formed by forging an iron material. An engagement groove 24a meshing with the serration portion 20a of the steering shaft 20 is formed in the upper peripheral surface of the fitting hole 24 along the axial direction. A tapered surface 24b is formed on the peripheral surface of the steering shaft 20. The tapered surface 24b is sloping downward and expands into which the tapered portion 20b of the steering shaft 20 is fitted.

The upper surface 21a of the boss 21 is formed in a smooth annular flat surface, while the lower surface 21b as an end surface of the boss 21 has a smooth annular flat surface 25, 3 Positioning concave portions 26a, 26b, 26c and two adjusting concave portions 27a, 27b are formed.

The positioning recesses 26a, 26b, 26c
Is closed on the steering shaft 20 side, that is, the fitting hole 24 side.
Is closed and the lower surface 21b
c to form a positioning recess 26
a and the circumferential clearances L ₁ , L ₁ between the positioning recesses 26b, 26c adjacent to both sides of the positioning recess 26a, respectively.
₁ are equal to each other, and the separation dimension L _1, the positioning recesses 26b facing the positioning recess 26a of one place, 26c
It is set to be larger than the circumferential direction of the separation dimension L ₂ between.

The adjusting recesses 27a and 27b are provided between the positioning recesses 26a and 26b and between the positioning recesses 26a and 26c, respectively, which are disposed via the long distances L ₁ and L _1. , 26b, 26c, and is formed to be open from the lower surface 21b of the boss 21 to the fitting hole 24 and the peripheral surface 21c.

After the boss 21, the boss plate 22, the metal core 15a of the spoke portion 15 and the rim metal core (not shown) of the rim portion 12 are welded, a lot number (not shown) is provided on the lower surface portion 21b of the boss 21. Is engraved.

On the other hand, an insertion hole 22a communicating with the fitting hole 24 of the boss 21 is formed in the boss plate 22, and a nut 30 is screwed into a bolt portion 20c formed at the tip of the steering shaft 20. The boss 21 and the boss plate 22 are integrally fixed to the steering shaft 20 by tightening. On the upper surface of the boss plate 22, a shock absorber 31 is attached by a clamp spring or the like (not shown) which buckles and deforms under impact and absorbs the impact, and has a mass absorber 32a. At the periphery of the lower surface of the boss plate 22, a core metal 15a of the spoke portion 15 is fixed by welding or the like.

A cover 18 covering the upper part of the boss 14
Is mounted, for example, by screwing to the shock absorber 31,
The side of the boss 14 is covered with a side cover 33 screwed to the boss plate 22, for example. In addition, the boss
The lower side of 14 is covered, for example, by a lower cover 34 screwed to the boss plate 22, and an axial hole of the lower cover 34 is formed with an insertion hole 34a facing the lower surface 21b of the boss 21. At the same time, on the lower surface of this lower cover 34,
A plurality of conductive slip rings 35 are attached concentrically with the insertion holes 34a.

In FIG. 1, reference numeral 41 denotes a cancel cam as a rotating member constituting a rotation direction indicator switch. The cancel cam 41 is formed in a substantially cylindrical shape from synthetic resin or the like. The upper end surface 41a of the cancel cam 41 is in close contact with the flat portion 25 of the lower surface portion 21b of the boss 21, and the upper end surface of the cancel cam 41 is
Positioning projections (cancel pins) 42, 42, 42 that fit into the respective positioning recesses 26a, 26b, 26c of the lower surface 21b of the boss 21 are projected from three places 41a. The cancel cam 41 is inserted into the insertion hole 34 of the lower cover 34.
a to cover the end of a steering shaft 20 and a steering column 43 that forms a vehicle body that is rotatably supported by fitting the steering shaft 20 so that each positioning projection 42 is positioned at each position of the boss 21. Recesses 26a, 26b,
It is positioned by fitting to 26c, and rotates integrally with the boss 21, ie, integrally with the steering wheel body 11.

On the other hand, a steering column 43 that rotatably supports the steering shaft 20 has a bracket 43a.
A combination switch 44 is fixed via the contact switch 46, and a contact piece 46 urged by a spring body 45, a rotation direction indicator switch (not shown) similar to that shown in the conventional example, and the like are incorporated in the combination switch 44. I have.

Then, the combination switch 44
Is provided with a cancel cam mounting mechanism 48 comprising a locking claw 44a and a spring body 47.
a and a spring piece 47, between which a mounting piece 41b protruding from the peripheral surface of the cancel cam 41 is pinched and elastically supported,
When the boss 21 is fitted to the steering shaft 20, the lower surface 21b of the boss 21 and the upper end surface 41a of the cancel cam 41 are in close contact with each other, and the tip of the contact piece 46 is slid into contact with each of the slip rings 35 so as to electrically connect. To be conducted.

An operation member having an operation lever protruding from the rotation direction indicator switch is incorporated so as to be rotatable by a predetermined angle around a neutral position at which no direction is indicated.

When the operation lever is rotated clockwise, a switch for instructing right rotation is connected, and the ratchet of the operation member is engaged with the stopper in the combination switch 44, and the operation member is moved. It is held at the right rotation instruction position. Then, after turning the steering wheel body 11 in the clockwise direction to turn the vehicle, and then returning the steering wheel body 11 in the counterclockwise direction, the cancel cam 41 that rotates together with the boss 21 of the steering wheel body 11 The projecting canceling projection comes into contact with the ratchet to release the engagement, and the operation lever is automatically returned to the neutral position.

When the operation lever is rotated counterclockwise, the switch for instructing left rotation is connected, and the operation lever is engaged and held at the instructed left rotation position. Then, after turning the steering wheel body 11 counterclockwise to turn the vehicle and then returning the steering wheel body 11 clockwise,
The canceling projection projecting from the cancel cam 41 that rotates together with the boss 21 of the steering wheel body 11 comes into contact with the ratchet to release the engagement and automatically return the operation lever to the neutral position. I have.

Next, the manufacturing process of the boss 21 of this embodiment and the process of fixing the boss 21 to the boss plate 22 will be described with reference to FIGS.

First, as shown in FIG. 5, an iron bar is cut to produce a columnar material 51.

As shown in FIG. 6, dies 52a to 52f each having a circular hole 52 having substantially the same diameter as the boss 21 to be manufactured are used as jigs for forging the material 51 to form the boss 21. Are provided at a predetermined interval and a plurality of die blocks 53 are provided at one side of the die block 53 as shown in FIG. 5 so as to be able to advance and retreat with respect to the respective circular holes 52 of the dies 52a to 52f. The first to sixth punches 55 to 60 and the other side of the die block 53, which are mounted in pairs with the dies 52a to 52f, and are formed in the respective circular holes 52 of the dies 52a to 52f.
The first and second knockout punches 61 and 62 and the first to fourth counter punches 63 to 66 which are provided so as to be able to move forward and backward with the leading end inserted are used.

In the forging step, first, a substantially columnar material 51 is mounted in a circular hole 52 whose diameter is smaller on one side than on the other side of the first die 52a, and the first knockout is performed. The conical tip 61a of the punch 61 is inserted into the circular hole 52 of the die 52a. In this state, the first punch 55 is advanced toward the first die 52a to hit the material 51. Then, a dish-shaped projection 55a having a conical tip is formed at the center of the tip of the first punch 55, so that a dish-shaped recess is formed at the center of one end face 51a of the material 51. Along with
The material 51 is formed by the tip portion 61a of the first knockout punch 61.
A conical concave portion is formed at the center of the other end surface 51b of the material 51, and a corner of the other end surface 51b of the material 51 is tapered by the first die 52a and rounded into a curved shape.

Next, the first knockout punch 61 is advanced to push out the material 51 from the first die 52a.

Then, by reversing the direction of the material 51,
The second die 52b is mounted in a circular hole 52 whose other side is smaller in diameter than one side, and the second knockout punch 62
The tip of the dish-shaped tip 62a having a flat top is inserted into the second die.
Insert into the circular hole 52 of 52b. In this state, the blank 51 is hit with the second punch 56 having a dish-shaped projection 56a having a conical tip at the center of the tip. Then, both ends of the material 51
The concave portions of 51a and 51b are slightly deeper and larger in diameter, respectively, and the corner of one end surface 51a of the material 51 is rounded by the second die 52b into a curved surface.

Next, the second knockout punch 62 is advanced, and the material 51 is extruded from the second die 52b.

Then, by reversing the direction of the material 51,
A first counter punch, which is mounted in the circular hole 52 of the third die 52c, forms a conical tip portion 63a, and has a substantially cylindrical shape having a diameter substantially equal to the fitting hole 24 of the boss 21. 63 is inserted into the circular hole 52 of the third die 52c.
The substantially cylindrical sleeve 67 fitted to the first counter punch 63 abuts against the other end surface 51b of the material 51 to support the material 51. In this state, a dish-shaped projection with a flat tip
When hit with the third punch 57 in which 57a is formed, the first
The counter punch 63 cuts into the concave portion of the other end surface 51b of the material 51, and the concave portions of both end surfaces 51a and 51b of the material 51 are formed further deeper.

Subsequently, the sleeve 67 fitted to the first counter punch 63 is advanced, and the first counter punch 63
The material 51 is extruded from the circular hole 52 of the third die 52c while extracting the material 51 from the concave portion of the other end surface 51b of the material 51.

The material 51 is mounted in the circular hole 52 of the fourth die 52d while maintaining the direction, and a conical tip portion 64a is formed. A second counter punch 64 formed in a cylindrical shape is inserted into the circular hole 52 of the fourth die 52d, and the concave portion 51b of the material 51 is inserted.
And a substantially cylindrical sleeve 68 fitted to the second counter punch 64 and the other end surface 51b of the material 51.
, And supports this material 51. In this state, it is hit with a fourth punch 58 which has a cylindrical shape with a through hole 58a formed in the axial center and a flat front surface 58b. Then
The second counter punch 64 is provided with both end surfaces 51a, 51b of the material 51.
Are punched together and fitted into the through hole 58a of the fourth punch 58, and a through hole 51c is formed in the axial center of the material 51 so as to communicate both end surfaces 51a and 51b.

Next, the sleeve 68 fitted to the second counter punch 64 is advanced, and the material 51 is extruded from the circular hole 52 of the fourth die 52d while extracting the material 51 from the second counter punch 64.

The material 51 is mounted in the circular hole 52 of the fifth die 52e while maintaining the direction, and a substantially cylindrical third counter punch 65 is fitted into the through hole 51c of the material 51. Then, the other end surface 51b of the material 51 is supported by the sleeve 69.

In this state, the blank 51 is hit with the fifth punch 59. As shown in FIGS. 5 and 7, the fifth punch 59 is formed in a cylindrical shape having a through hole 59a formed in the axial center portion thereof, and is formed on the front surface 59b at three locations separated from the through hole 59a. A projecting portion 59c for forming a positioning recess having a substantially prismatic shape protrudes therefrom. Further, a projecting portion 59d for forming an adjusting recess is formed to protrude from two places continuous with the through hole 59a.

Then, in the state of being hit with the fifth punch 59, three positioning concave portions 26a, 26b, 26c and two adjusting concave portions 27 shown in FIG.
a and 27b are formed.

Further, the sleeve 69 fitted to the third counter punch 65 is advanced, and while the third counter punch 65 is being extracted from the material 51, the material 51 is inserted into the circular hole of the die 52e.
Extrude from 52.

Then, the material 51 is mounted in the circular hole 52 of the sixth die 52f by reversing the direction of the material 51.
The fourth counter punch 66 is fitted into the through hole 51c of the hole 51, and the one end surface 51a of the material 51 is supported by the sleeve 70. The fourth counter punch 66 is formed with a substantially columnar projection 66b having a tapered portion 66a that expands rearward.
A sleeve 70 having a smooth front surface 70a
Are fitted.

Then, in this state, the blank 51 is hit with the sixth punch 60. The sixth punch 60 has a cylindrical shape in which a through hole 60a is formed in an axial center portion, and a front surface 60b is formed in a smooth planar shape.

When hit by the sixth punch 60, the tapered surface 24b of the boss 21 is formed at one end of the fitting hole 24 so as to be inclined so as to expand, and the smooth upper surface 21a and the lower surface 21 are formed.
b is formed, and the height dimension between the upper surface 21a and the lower surface 21b is accurately adjusted.

Next, an engaging groove 24a is formed in the upper part of the fitting hole 24. As one forming means, a broaching rod for forming an engaging groove is inserted into the fitting hole 24 and pulled out. As another means, there is provided a fifth counter punch (not shown) in which an engagement groove forming portion is provided at a portion corresponding to the projection 66b of the fourth counter punch 66 by forging. There is a method of forming.

Then, the boss 21 formed in this forging step is formed.
As shown in FIG. 8, the upper surface 21a is held from above and below by a pair of resistance welding electrodes 71, 72 in a state where the upper surface 21a is in contact with welding projections 22b formed at a plurality of locations on the lower surface of the boss plate 22, A predetermined current flows while being pressurized. Then the boss
Resistance heat is generated at the contact portion of the boss plate 22 with the welding protrusion 22b, and the welding protrusion 22b is melted by using the resistance heat, so that the boss 21 and the boss plate 22 adhere to each other by resistance welding. It is fixed.

As described above, according to this embodiment, the boss 21 can be easily manufactured by forging, and the steering wheel body
Eleven manufacturing efficiency can be improved.

The canceling cam 41 is positioned by fitting a positioning protrusion 42 projecting from the canceling cam 41 of the rotation direction indicator switch into a positioning recess 26a provided on the lower surface 21b of the boss 21. Rotate with the steering wheel body 11
The operation lever can be disengaged and automatically returned to the neutral position by the canceling ridge 41.

The positioning recesses 26a, 26b of the boss 21
, 26c can be formed integrally with the boss 21 by forging, so that a complicated operation of forming a positioning recess by drilling or the like on the boss 21 becomes unnecessary, and the production efficiency of the boss 21 can be improved. The manufacturing efficiency of the steering wheel main body 11 using the same can be improved.

Further, the positioning recesses 26a, 26 of the boss 21 are formed.
b, 26c is opened and formed from the lower surface portion 21b of the boss 21 toward the circumferential surface 21c, Do You steering shaft 20 side
Since the direction toward the fitting hole 24 is closed , the material 51 is hit with the sixth punch 60 in the forging step shown in FIG. 24b, each positioning recess 26a, 26b, 26
It is possible to suppress the occurrence of burrs and the like in c, to improve the dimensional accuracy of each positioning concave portion 26a, 26b, 26c of the boss 21, and to ensure the connection with the cancel cam 41.
That is, the occurrence of burrs protruding from the fitting hole 24 can be suppressed.
As a result, deburring work can be reduced and the occurrence of burrs can be suppressed.
Easily increase accuracy without having to set the shape to control
Can reduce manufacturing costs.
You.

Further, since a flat surface portion 25 facing the vehicle body is formed on the lower surface portion 21b of the boss 21, the electrode 72 for resistance welding can be in close contact with the flat surface portion 25 to stabilize the current value of resistance welding. Thus, the boss 21 can be reliably welded to the boss plate 22 and the lot number can be easily marked on the lower surface 21b.

Then, the positioning recess on the lower surface 21b of the boss 21
Since the adjusting recesses 27a and 27b are formed between the positioning recesses 26a and 26b and between the positioning recesses 26a and 26c, the variation in the volume of the raw material 51 is determined by the depth of the adjusting recesses 27a and 27b in the boss 21 forging process. The boss 21 can be adjusted, and the accuracy of the portion other than the adjusting recesses 27a and 27b of the boss 21 is improved. In particular, the longitudinal dimension H of the boss 21 shown in FIG.
It is possible to secure ₁ and the lower surface portion 21b and a surface area S ₂ of the smooth flat portion 25.

That is, it is necessary to accurately set the longitudinal dimension H of the boss 21 in order to eliminate vertical variations when the boss 21 is fixed to the steering shaft 20, and to determine the portion of the boss 21 that contacts the resistance welding electrodes 71 and 72. Boss with constant area
To ensure resistance welding between 21 and boss plate 22,
It is necessary to accurately set the area S _{1 of the} upper surface portion and the area S ₂ of the smooth flat surface portion 25 of the lower surface portion 21b.

However, the volume of the material 51 of the boss 21 slightly varies, and it is difficult to make it completely uniform. When the volume of the material 51 is larger than the predetermined volume, for example, the longitudinal dimension H of the boss 21 becomes larger than the predetermined dimension.

[0062] Also, when the volume of material 51 is smaller than the predetermined volume at the time of forming the positioning recesses 26a, 26b, and 26c in forging, is placed through the long separation dimension L _1, L ₁ Between the positioning recesses 26a and 26b and the positioning recesses
An irregular concave portion 74 as shown in FIG. 10 is formed between 26a and 26c. Then, each positioning recess 26a, 26b, 26c
Becomes uneven, and the lower surface 21 of the boss 21
the area S ₂ of the b smooth flat portion 25 becomes non-uniform, the area of the portion contacting to the resistance welding electrode 72 is not constant, even unstable value of the current flowing through the welding portion, further,
This causes a problem that it is difficult to imprint a lot number or the like on the lower surface portion 21b of the boss 21.

[0063] Therefore, in this embodiment, a long separation dimension L _1, L ₁ is disposed via a positioning recess 26a, 26b
Since the adjusting recesses 27a and 27b are formed beforehand between the positioning recesses 26a and 26c, respectively, as shown in FIG. 9, when the volume of the material 51 is close to a predetermined volume, a deep adjusting recess 75 is formed in advance. When the volume of the material 51 is larger than the predetermined volume by, for example, several%, a slightly shallow adjusting concave portion 76 is formed, and when the volume of the material 51 is further larger by several%, A shallow adjusting recess 77 is formed. In this way, by adjusting the depth dimension of each of the adjusting concave portions 27a and 27b, the dimensions of other portions can be set accurately. The area S _{1 of the} upper surface and the lower surface 21
b smooth and accurately set the area S ₂ of the flat portion 25 of, homogenized by welding strength current flow during resistance welding can be made constant a.

In this embodiment, the lower surface 21b of the boss 21 is provided.
Each of the positioning recesses 26a, 26b, and 26c is opened toward the outer peripheral surface 21c. However, as shown in FIG. 11, a positioning recess 81 that opens toward the inner fitting hole 24 is formed. As shown in FIG. 12, a positioning recess 82 having a circular cross section that opens only downward can be formed.
However, when the positioning recesses 81 and 82 are formed and the tapered surface 24b is formed below the fitting hole 24 by hitting with the fourth counter punch 66 in the forging process shown in FIG. In the case of the positioning recesses 81 to be formed, burrs are easily formed at the inner ends of the positioning recesses 81, and in the case of the positioning recesses 82 that open only downward,
Each positioning recess 82 is easily deformed flat. Therefore, when forming these positioning recesses 81 and 82, it is necessary to set the shapes of the positioning recesses 81 and 82 formed by forging in consideration of these deformations in advance.

Further, in each of the above embodiments, the positioning recesses are formed at three places, respectively. However, the positioning recesses are not limited to three places, and may be formed at four or more places. Also in this case, by forming the adjusting concave portion in the portion where the dimension between the positioning concave portions is large, it is possible to effectively prevent the generation of the irregular concave portion 74 on the lower surface portion 21b.

[0066]

According to the steering wheel of the first aspect, the boss can be easily manufactured by forging, and the manufacturing efficiency of the steering wheel body can be improved. By fitting a positioning protrusion protruding from a rotating member provided on the rotation direction indicator switch into a positioning recess provided on the end face of the boss, the rotating member can be positioned and rotated together with the steering wheel body. This positioning recess is used to fix the fixed part fixed to the steering shaft by forging.
Since it can be formed integrally with the provided boss, a complicated operation for forming the positioning recess by drilling or the like on the boss is not required, and the manufacturing efficiency can be improved. The boss positioning recess is
When the direction toward the steering shaft is blocked
In addition, since the opening is formed from the direction toward the vehicle body to the radially outward direction of the steering shaft, deformation of the positioning recess in the forging process can be suppressed, and the dimensional accuracy of the boss can be improved , and the steering can be improved.
Suppress burrs toward the shaft and easily increase accuracy
Can be

According to the steering wheel of the second aspect, the boss can be easily manufactured by forging, and the manufacturing efficiency of the steering wheel body can be improved. By fitting a positioning protrusion protruding from a rotating member provided on the rotation direction indicator switch into a positioning recess provided on the end face of the boss, the rotating member can be positioned and rotated together with the steering wheel body. This positioning recess has a fixed part that is fixed to the steering shaft by forging.
Since it can be formed integrally with the obtained boss, a complicated operation for forming the positioning recess by drilling or the like on the boss is not required, and the production efficiency can be improved. The boss has a smooth flat surface on the end face toward the vehicle body, so that resistance welding electrodes can be in close contact with this flat portion, stabilizing the resistance welding current value, and incorporating the boss into the steering wheel body. Can be assured. Because the adjusting recess was provided between the positioning recesses provided at a plurality of positions on the end face, in the forging process of the boss,
Variations in the volume of the material can be adjusted by adjusting the depth of the adjusting recess, improving the accuracy of the boss other than the adjusting recess,
In particular, the longitudinal dimension of the boss and the smoothness of the end face can be ensured.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 2 showing an embodiment of the steering wheel of the present invention.

FIG. 2 is a plan view of the steering wheel body according to the first embodiment.

FIG. 3 is a perspective view of the boss.

FIG. 4 is a bottom view of the boss.

FIG. 5 is an explanatory view showing a manufacturing process of the boss.

FIG. 6 is a perspective view showing a jig used for manufacturing the boss.

FIG. 7 is a perspective view showing a jig used for manufacturing the boss.

FIG. 8 is an explanatory view showing a manufacturing process of the steering wheel main body.

FIG. 9 is an explanatory diagram showing an operation of the boss.

FIG. 10 is an explanatory view showing a problem of a boss by forging.

FIG. 11 is a perspective view of a boss showing another embodiment of the present invention.

FIG. 12 is a perspective view of a boss showing still another embodiment of the present invention.

FIG. 13 is a partially cutaway front view showing a conventional steering wheel.

[Explanation of symbols]

11 Steering wheel body 20 Steering shaft 21 Boss 21b Lower surface 24 as an end face 24 Fitting hole 25 as a fixing part 25 Flat part 26a Positioning concave part 41 Cancel cam as a rotating member 42 Positioning protrusion 43 Steering column forming the vehicle body

Claims (2)

(57) [Claims] 1. A steering wheel having a metal boss fixed to a steering shaft rotatably supported on a vehicle body and having a steering wheel body to which a rotation direction indicator switch is connected, wherein the boss is , Fixed part fixed to steering shaft
And a positioning recess provided in the rotation direction indicator switch and fitted with a positioning protrusion protruding from a rotating member that rotates together with the steering wheel body , by forging.
The positioning recess is formed integrally with the steering shaft.
A steering wheel, wherein an opening is formed from a direction toward the vehicle body to a radially outward direction of the steering shaft. 2. A steering wheel having a metal boss fixed to a steering shaft rotatably supported on a vehicle body and having a steering wheel body to which a rotation direction indicator switch is connected, wherein the boss is A fixed portion fixed to a steering shaft, an end surface portion having a smooth flat surface portion facing the vehicle body, and provided at a plurality of positions on the end surface portion, opening at least in a direction toward the vehicle body, and indicating the rotation direction. A positioning recess provided in the switch and fitted with a positioning projection projecting from a rotating member that rotates together with the steering wheel body, and an adjusting recess provided between these positioning recesses are forged.
A steering wheel formed integrally with the steering wheel.