JP2003026003A - Steering wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily improve vibration characteristic of a steering wheel. SOLUTION: An upper shell 21 and a lower shell 22 are mutually combined to form a hollow core metal unit 11. A damping unit storage part B is formed inside a rim core metal unit part 15. A damping unit W is stored in the damping unit storage part B. The damping unit W is provided with a plurality of branch chambers C therein. Each branch chamber C is filled with fluid by leaving a space, respectively. When the steering wheel vibrates, the fluid in each branch chamber C moves and comes into contact with an internal wall of each branch chamber C to suppress the vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering wheel provided with vibration suppressing means for improving vibration characteristics.

[0002]

2. Description of the Related Art Conventionally, in a steering wheel used for steering a vehicle such as an automobile, vibrations caused by rotation of an engine and vibrations from a road surface during traveling are transmitted to a steering wheel fixed to an end of a steering shaft on an occupant side. The wheel is vibrating. At this time, a maximum point of vibration appears at the resonance frequency peculiar to the steering wheel, and the vibration of this frequency causes a large vibration of the steering wheel, which causes a problem that an occupant who grips and operates the steering wheel feels uncomfortable. is doing.

[0003] In this respect, for example, the actual exploitation Sho 62-64675
As disclosed in Japanese Patent Publication No. 2-129967 or Japanese Utility Model Laid-Open No. 129967, a damping device for adjusting a natural resonance frequency by mounting a weight (damper) supported by rubber legs inside a steering wheel is used. .

[0004]

According to the above-mentioned conventional structure, a weight having a considerable mass and volume is supported by a rubber leg, and a predetermined stroke is provided so that the weight, that is, the load on the rubber leg does not collide with a peripheral member. Therefore, the problem of increase in mass of the steering wheel as a whole is likely to occur. In addition, the volume occupied by the vibration damping device is large, and the position where the vibration damping device can be mounted is
As shown in Japanese Laid-Open Patent Publication No. 29967, only a limited portion of a steering wheel such as a boss portion, or as shown in Japanese Utility Model Laid-Open No. 62-64675, it is arranged by using the entire diameter of the rim portion. ing.

However, there is a demand for arranging a collision safety device such as an airbag module or various operating mechanisms such as a horn switch on the steering wheel, and the steering wheel is arranged in the circumferential direction of the rim portion during gripping operation. Since there is a demand for realizing a uniform and soft feel and also for realizing a suitable design, it is difficult to dispose the weight on the boss portion or the rim portion.

Further, the boss portion is a base point for fixing the steering wheel to the steering shaft, and the spokes and the rims separated from the base point are designed to give rigidity to suppress the vibration, thereby effectively suppressing the vibration. Although it can be suppressed, the spokes and rims must have favorable crushing deformation characteristics against external force, and the design that achieves both these deformation characteristics and vibration characteristics at a high level will eventually be repeated as a result of repeated design and experiments. Being completed, it is a difficult task that requires a large amount of development investment and a research period. further,
Regarding the configuration in which a weight having a completely different structure from that of the other portion is combined with a part of the rim portion, there are many technical problems to be newly overcome.

The present invention has been made in view of the above points, and an object of the present invention is to provide a steering wheel that can easily improve vibration characteristics.

[0008]

A steering wheel according to a first aspect of the present invention includes a rim core metal part for gripping operation, a boss core metal part connected to a steering shaft, and these boss core metal parts and rim core. A cored bar having a spoke cored bar connecting the metallized part, and a sealed container part provided along at least a part of the rim cored bar part and a fluid movably enclosed in the container part. And a vibration suppressing means.

In this structure, when the steering wheel vibrates, the fluid moves in the container and collides with the inner wall of the container, so that the vibration suppressing means vibrates in a phase different from that of the other parts. Resonance is suppressed, the vibration characteristics are efficiently adjusted, and the operation feeling is improved. By using the fluid, the degree of freedom in the shape of the vibration suppressing means including the container is improved, and the versatility is improved. Further, by using the fluid, it becomes easy to suppress the collision noise and the structure is simplified. Since the vibration characteristics are adjusted efficiently, the vibration suppressing means can be made lighter in weight, the rotational moment can be suppressed, and the operational feeling can be improved.

According to another aspect of the steering wheel of the present invention,
In the steering wheel according to the first aspect, the rim cored bar portion has a substantially annular shape, and the vibration suppressing means has a substantially arcuate shape along the rim cored bar portion.

With this structure, the vibration suppressing means can be provided by effectively utilizing the space of the rim portion of the steering wheel.

The steering wheel according to claim 3 is
The steering wheel according to claim 1 or 2, wherein the rim cored bar portion includes a first rim cored bar portion forming section.
The half shell, the second half shell provided with the second rim cored bar component, and the first rim cored bar in a state where the first half shell and the second half shell are superposed on each other. The vibration suppressing means is housed in the hollow portion, and includes a hollow portion formed between the structural portion and the second rim cored bar portion forming portion.

With this structure, the vibration suppressing means can be provided by effectively utilizing the space of the rim portion of the steering wheel.

The steering wheel according to claim 4 is
In the steering wheel according to any one of claims 1 to 3, the container portion of the vibration suppressing means is provided with a plurality of compartments that are partitioned from each other and are capable of enclosing a fluid.

In this structure, a desired vibration characteristic can be obtained by enclosing the fluid in an appropriate single chamber or a plurality of chambers with respect to the plurality of chambers. In addition, it becomes easy to move the fluid within a relatively small range, and the damping characteristics for a relatively high vibration frequency are easily improved.

The steering wheel according to claim 5 is
In the steering wheel according to the second or third aspect of the invention, the container portion of the vibration suppressing means includes a plurality of compartments that can each contain a fluid and that are arranged side by side in the circumferential direction of the rim core metal portion.

In this structure, a desired vibration characteristic can be obtained by enclosing the fluid in an appropriate single chamber or a plurality of chambers with respect to the plurality of chambers. In addition, it becomes easy to move the fluid within a relatively small range, and the damping characteristics for a relatively high vibration frequency are easily improved. Furthermore, since the fluid does not move a long distance in the circumferential direction, the time difference in the generation of the moment when the rim portion of the steering wheel is rotated is reduced, and the operability is improved.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a steering wheel of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 1 denotes a steering wheel of an automobile. The steering wheel 1 is a steering wheel body 2 and an airbag device (airbag module) which is a center pad mounted on the occupant side of the steering wheel body 2. ) 4 and so on.
The steering wheel 1 is, as shown in FIG.
Steering shaft S on the vehicle body side that is a steering shaft
The steering shaft S is mounted on the vehicle and is normally provided in the vehicle in a tilted state, and in the straight traveling state of the vehicle, the vicinity of the position F is the upper end and the front end. In describing the configuration of the above, the occupant side that is the airbag device 4 side, that is, the front side is the upper side, the opposite side of the occupant side, that is, the steering shaft S side that is the steering shaft on the vehicle body side, that is, the rear side, is the lower side, The front side of the vehicle, that is, the windshield side above the front side will be referred to as the front side, the rear side of the vehicle, that is, the lower rear side will be referred to as the rear side or the front side, and the axis of the steering shaft S will be referred to as the operation axis O.

The overall shape of the steering wheel main body 2 is, for example, a substantially annular shape, and an annular rim portion 5 which is an annular shape for a gripping operation, which is also called a grip portion or a ring portion, and the rim portion 5. It includes a boss portion 6 located inside and fixed to the steering shaft S, and a plurality of, in the present embodiment, three spoke portions 7 that connect the rim portion 5 and the boss portion 6.

Further, the structure of the steering wheel body 2 is provided with a core metal 11, a covering portion 12 which covers a part of the core metal 11 and is incorporated therein, and a lower cover (lower cover) 14.

As shown in FIGS. 1 to 3, the cored bar 11 can also be called a handle cored bar and is an annular rim core for reinforcing the rim portion 5 according to the overall shape of the steering wheel body 2. A metal portion (a rim core metal portion for gripping operation) 15, a boss core metal portion (boss plate portion) 16 located inside the rim core metal portion 15 to reinforce the boss portion 6 and be attached to the steering shaft S; Reinforce the spokes 7, that is,
The first half shell facing the occupant has a shape having a plurality of, in the present embodiment, three spoke core metal parts 17 for connecting the rim core metal part 15 and the boss core metal part 16 to each other. And a lower shell 22 as a second half shell facing the vehicle body are combined to form a hollow portion A inside,
A part of the hollow portion A is formed in a hollow shape as a vibration damping unit housing portion B which is a vibration suppressing means housing portion. The rim core metal part 15 and the boss core metal part 16 are formed in a hollow shape having a closed tubular shape in cross section, and the boss core metal part 16 holds a part inside the hollow part to fix the shaft. The boss body 23 constituting the is fixed. Further, hereinafter, the connecting portion between the rim core metal portion 15 and the spoke core metal portion 17 is the outer connecting portion 18, and the connecting portion between the boss core metal portion 16 and the spoke core metal portion 17 is the inner connecting portion 19.
As described below.

The upper and lower shells 21 and 22 are formed by press-forming a steel plate, and each has a thickness dimension of 1.
It is integrally formed by deep drawing a 0 mm SPCE steel plate. The upper and lower shells 21 and 22 include a rim edge coupling portion 15a along the outer circumference and the inner circumference of the rim core metal portion 15, a spoke edge coupling portion 17a along both sides of the spoke core metal portion 17, and
The boss core metal parts 16 are connected by boss edge connection parts 16a along the outer periphery thereof.

The upper shell 21 includes a rim upper portion 31, a spoke upper portion 32, and a boss upper portion 33 as a first rim cored bar portion constituting portion.
Is equipped with. A circular hole 33a is formed in the center of the boss upper portion 33, and a plurality of circular holes 33a are formed at equal intervals on the circumference centered on the circular hole 33a, for example, at three positions.
A protrusion 33b protruding downward is formed.
A connecting portion 33, which is an annular protrusion that is located on the outer peripheral side of 3b and protrudes upward in a substantially U-shaped cross section around the circular hole 33a.
c is formed concentrically with the circular hole 33a. The inside of the connecting portion 33c is arranged at a position lower than the outside of the connecting portion 33c. Further, on both sides and the rear side of the boss upper portion 33, seat portions 37 for restricting the height position of the airbag device 4 are formed so as to project upward.

The spoke upper portions 32 are extended from both side portions and the rear side portion of the boss upper portion 33 so as to be inclined upward, and the dimension in the width direction is substantially constant along the longitudinal direction, but the outer connecting portion 18 is provided.
In the vicinity of, a spoke core metal upper diameter large portion 32a whose width dimension smoothly and continuously increases is formed toward the outer connecting portion 18.

Further, the rim upper portion 31 is formed in a plane annular shape, and near the outer connecting portions 18 on both sides, a rim core metal upper diameter large portion 31a having a height dimension larger than that of the other portions is formed.

Further, on the rim upper portion 31, the position F which is the farthest point from each outer connecting portion 18 is set substantially at the center, and the lower side, that is, the rim core metal portion, is arranged at a predetermined interval in the circumferential direction of the rim portion 5. A pair of beads 35, 35, which are recessed toward the inside of 15, are integrally formed. Further, each bead 35 has a substantially triangular shape in a plan view, and portions facing each other are substantially vertical locking surfaces that constitute the vibration damping unit housing portion B.

Further, in the vicinity of the inner connecting portions 19 on both sides, a bracket 39 forming a mounting seat 38 is integrally formed so as to be continuous with the boss upper portion 33 and the spoke upper portion 32. Each bracket 39 has a horizontal plate shape and a plurality of through holes 39a and 39b are formed therein.

Further, the rim upper portion 31, each spoke upper portion 32,
At the edge of the boss upper portion 33, as shown in FIG. 3 for the rim upper portion 31, a flat plate-shaped base portion 41 and a vertical wall portion 42 extending downward from the edge portion of the base portion 41 are formed. With
A plastically deformable continuous plate-shaped upper flange portion 44a and a winding tightening portion 44b extending downward from the outer end portion of the upper flange portion 44a continuously to the lower end of the vertical wall portion 42. The wrapping part 44 is formed.

On the other hand, like the upper shell 21, the lower shell 22 is provided with a rim lower portion 51, a spoke lower portion 52, and a boss lower portion 53 as a second rim cored bar portion constituting portion. A circular hole 53a having a diameter larger than that of the circular hole 33a of the boss upper portion 33 is formed in the center of the boss lower portion 53, and the circular hole 53a is formed.
A plurality of, for example, three protrusions 53b are formed at equal intervals on the circumference centering on the center and project upward. These protrusions 53b are 6 times larger than the protrusions 33b on the boss upper portion 33.
It is formed at a position offset by 0 degree. Furthermore, this protrusion 53
An annular connecting portion 53c, which is located on the outer peripheral side of b and protrudes upward in a substantially U-shaped cross section around the circular hole 53a, is formed concentrically with the circular hole 53a. And the connecting part of this lower shell 22
The outer diameter of 53c is smaller than that of the connecting portion 33c of the upper shell 21, and the inner diameter thereof is larger than that of the connecting portion 33c of the upper shell 21, so that the 53c can be accommodated in the connecting portion 33c of the upper shell 21. In the vicinity of the inner connection portion 19, that is, on both sides and the rear side of the boss upper portion 33, a hole portion 53d facing a seat portion 37 of the boss upper portion 33, into which a self-tapping screw (not shown) is screwed, is formed. Are formed.

Further, the lower spokes 52 extend obliquely upward from both sides and the rear side of the lower boss 53, and the dimension in the width direction is substantially constant along the longitudinal direction, but the outer connecting portions 18
In the vicinity of, a spoke mandrel lower diameter large portion 52a is formed facing the outer connecting portion 18 and whose width dimension smoothly and continuously increases.

Further, the rim lower portion 51 has a plane annular shape, and in the vicinity of the outer connecting portions 18 on both sides, a rim core bar lower diameter large portion 51a having a height dimension larger than other portions is formed.

Further, in the rim lower portion 51, a position F which is the most distant point from each outer connecting portion 18 is set substantially at the center, and the upper portion, that is, the rim core metal portion 15 is provided at a predetermined interval in the circumferential direction of the rim portion 5. A pair of beads 55, 55, which are recessed toward the inside of, are integrally formed. Further, each bead 55 has a substantially triangular shape in a plan view, and portions facing each other are substantially vertical locking surfaces.

Further, in the vicinity of the inner connecting portions 19 on both sides, a bracket 59 constituting the mounting seat 38 is integrally formed so as to be continuous with the boss lower portion 53 and the spoke lower portion 52. Each bracket 59 has a horizontal plate shape and a plurality of through holes 59a and 59b are formed therein.

Further, the rim lower portion 51, each spoke lower portion 52,
At the edge of the boss lower portion 53, as shown in FIG. 3 for the rim core metal portion 15, for example, a flat plate-like base portion 61 and a vertical wall portion 62 extending upward from this edge portion are formed. With
A horizontal plate-shaped flange portion 64 is formed continuously with the upper end of the vertical wall portion 62.

The boss body 23 is made of iron material by forging, casting,
Alternatively, it is formed by NC cutting or the like using an NC machine tool. In the present embodiment, by forging, a cylindrical portion 23a having a substantially cylindrical shape and a boss flange portion 2 having a substantially disk shape are formed.
3b and 1b are manufactured together. Then, on the inner surface portion of the tubular portion 23a, a protrusion portion (serration portion) that meshes with the wavy protrusion formed on the outer peripheral portion on the tip side of the steering shaft.
23c is engraved. Further, notch portions 23d, which are notched in a semicircular shape, are formed at six locations at equal intervals on the outer peripheral portion of the boss flange portion 23b. Further, a canceling portion 23e, which is a rectangular recess, is formed at the lower end of the tubular portion 23a. The canceling portion 23e engages with a cancel pin provided on the steering column side (not shown) for automatically returning the operating lever of the lamp of the direction indicator.

The cored bar 11 is constructed by abutting and connecting the upper and lower shells 21 and 22 with the boss body 23 sandwiched between the cored bar 11 and the rim upper part 31 at the front end of the rim cored bar part 15. Between the rim lower portion 51 and the rim lower portion 51, the locking surfaces of the beads 35 and 55 are used as both ends in the longitudinal direction, and a vibration damping unit housing portion B is formed in a part of the hollow portion A.

Next, the vibration damping unit W as vibration suppressing means housed in the vibration damping unit housing B will be described.

As shown in FIGS. 3 and 4, the vibration damping unit W is provided with a sealed rectangular cylindrical container W1 having a rectangular cross section which is arcuate in shape by the curvature of the rim cored bar 15. The outer shape of the container portion W1 is substantially the same as the inner shape of the vibration damping unit housing portion B, and can be suppressed at the same time when the upper and lower shells 21 and 22 are joined by hemming described later. The rim cored bar portion 15 is positioned by the beads 35 and 55 in the circumferential direction. In this manner, the container portion W1 is fitted and fixed in the vibration damping unit storage portion B so as not to rattle, so to speak, the vibration damping unit W is attached along the rim cored bar portion 15. There is.

Further, the container portion W1 is formed by combining the container main body portion W1a and the lid portion W1b in an airtight and liquid-tight manner to form one or a plurality of fluid storage portions which are partitioned from each other inside. In the present embodiment, a plurality of compartments C arranged along the circumferential direction of the rim cored bar portion 15 are formed as the fluid storage portion. Also, for example, these container body W1a and lid W1b
And are integrally formed by injection molding polypropylene resin, nylon 66 resin, or the like. Further, in the present embodiment, as shown in FIG. 4 (b), the connecting portion between the container body portion W1a and the lid portion W1b is airtightly joined by welding. However, the joining portion is not limited to welding but so-called friction. Welding or vibration welding such as ultrasonic horn welding may be used. Also, the container body W1a and the lid W1b
The joint portion with and may be hermetically fitted by a so-called snap fit, and an O-ring or the like may be appropriately combined as a seal for improving hermeticity.

Inside the sealed container W1, that is, in each of the compartments C, a part of the compartments C or all of the compartments C are filled with a fluid L, respectively. Then, each fluid L is enclosed in a predetermined amount, for example, about 70% of the total volume of each compartment C so as to occupy a part of the interior of each compartment C instead of the entire interior. Has been done. That is, each fluid L is movable inside each compartment C and is in a state of being able to collide with the inner wall portion of the compartment C. Further, the fluid L has a predetermined viscosity and density, and in this embodiment, the viscosity is 0.65 cps and the density is 0.7 g.
Silicone oil of / cm ³ or machine oil having a viscosity of 46 cps and a density of 0.87 g / cm ³ is used.

In the manufacturing process of the core metal 11, the boss body 23 is arranged between the boss upper portion 33 of the upper shell 21 and the boss lower portion 53 of the lower shell 22, and the boss body 23 is arranged between the rim upper portion 31 and the rim lower portion 51. The vibration damping unit W is arranged in the vibration damping unit storage portion B, and the upper and lower shells 21 and 22 are overlapped. At this time, the tubular portion 23a of the boss body 23 is projected downward from the circular hole 53a of the boss lower portion 53, and the boss flange portion 23b is sandwiched between the boss upper portion 33 and the boss lower portion 53. The projections 33b and 53b are engaged with the notches 23d at the six positions of the space 23b from the top and bottom, and the upper and lower shells 21 and 22 and the boss 23 are positioned in the rotational direction.

A flange 64 provided along the edge of the lower shell 22 with the upper and lower shells 21 and 22 stacked on each other.
Are accommodated in the holding portion 44 provided along the edge of the upper shell 21. In this state, the winding tightening portion 44b of the holding portion 44 is hemmed to join the upper and lower shells 21 and 22. That is,
By hemming with an automatic machine, the winding part 44b which is a vertical wall
Inwardly, further applying force to the winding tightening portion 44b and folding back, deforming the flange portion 64 of the lower shell 22 so as to wrap it in parallel, and winding up to the lower surface side to form the rim edge coupling portion 15a, Join the shells 21 and 22 of. In this state,
The rim core metal part 15 and the spoke core metal part 17 have a closed tubular shape in cross section, and a hollow part A and a damping unit housing part B are formed inside. Note that, for example, the rim edge coupling portion 15a of the rim cored bar portion 15
With regard to the above, it is also possible to form a concave portion by performing so-called punching at a predetermined interval and engage the upper and lower shells 21 and 22 to prevent rotation in the circumferential direction.

Further, the boss core metal part 16 includes the upper and lower connecting parts 33.
One of the c and 53c is accommodated in the other by closely fitting, and is fixed without being fixed.
A weak portion (intermediate weak portion) X, which is deformable by an external force, is formed inside the 33c and 53c and outside the boss body 23. Further, the cross-sectional shape of the weak portion X is wider and smaller than the cross-sectional shape of the hollow portions of the rim core metal portion 15 and the spoke core metal portion 17,
That is, the dimension in the height direction, which is the direction along the operation axis O, is small, and the dimension in the width direction, which is the direction orthogonal to the operation axis O, is large.

Further, the boss 23 is fixed to the lower shell 22 by spot welding or the like at a predetermined position. The boss body
23 may be fixed to one of the upper and lower shells 21 and 22, or may be fixed to both of the upper and lower shells 21 and 22.

Further, in this state, the rim cored bar portion 15 and the spoke cored bar portion 17 are connected to the outer connecting portion 18 connected to each other, and the spoke cored bar portion 17 has a dimension in the width direction more than other portions. The spoke core metal large diameter portion 67 having a greatly enlarged cross-sectional area is configured. In addition, the rim core metal part 15 is continuous with the outer connecting parts 18 on both sides.
A rim cored bar large diameter portion 68 having a larger dimension in the height direction and a larger cross-sectional area than the other portions is formed on both side portions of the.

Further, in this state, the upper and lower brackets 3
The mounting seat 38 is formed by aligning and stacking 9 and 59. The mounting seat 38 includes a positioning hole 38a in which the through holes 39a and 59a communicate with each other and a mounting hole 38b in which the through holes 39b and 59b communicate with each other.

Then, as shown in FIG. 2, the cover 12 and the lower cover 14 are attached to the cored bar 11 thus constructed to form the steering wheel body 2.

The covering portion 12 is provided with rim covers 71 and 72 which are divided into upper and lower parts, and covers the rim covers 71 and 72 by partially covering the rim cored bar portion 15 and the spoke cored bar portion 17. The upper and lower rim covers 71, 72 are formed by injection molding polypropylene resin, for example. Furthermore, if necessary, for example, a skin material such as natural leather such as cow leather or artificial leather.
The rim covers 71 and 72 are wrapped around the outer circumferences of the rim covers 71 and 72 and sewn to cover the entire rim covers 71 and 72.

The lower cover 14 is integrally formed of, for example, synthetic resin in a shape that covers a part of the boss core metal portion 16 and the spoke core metal portion 17, and a self-tapping screw (not shown) is installed in a predetermined through hole. It is inserted from the side and screwed into the hole 53d of the lower shell 22 to fix it with a screw. The seat portion 37 of the upper shell 21, which faces the hole portion 53d of the lower shell 22, has a threaded portion of the self-tapping screw that protrudes upward through the hole portion 53d. It has the function of avoiding contact with.

Further, a working hole 14a is formed in the lower cover 14 so as to face the mounting seat 38 of the cored bar 11.

Further, the airbag device 4 has a bag-shaped airbag (not shown) and an inflator for supplying gas to the airbag attached to the metal base plate 4a.
Further, it is configured by covering the upper side with a cover body 4b that is broken by the pressure at which the airbag is inflated and deployed. Further, the base plate 4a is provided with a pair of nut portions on both sides each having a downwardly directed screw hole, and a positioning protrusion is provided near the nut portions.

The airbag device 4 has a core metal 11
Of the base plate 4a is abutted on the seat portion 37 of the upper shell 21 and positioned in the height direction, and the positioning protrusion is inserted into the positioning hole 38a of the mounting seat 38. Positioned horizontally (laterally). The upper and lower through holes 39a and 59a that form the positioning hole 38a are
The through hole 59a of the lower shell 22 is formed to be larger than the through hole 39a of the upper shell 21, so that the positioning projection inserted in the through hole 39a does not come into contact with and interfere with the lower shell 22. Then, in this state, the working hole 14a of the lower cover 14
The airbag device 4 is fixed to the steering wheel main body 2 by screwing a bolt 75 inserted from below through the nut portion of the base plate 4a through the mounting hole 38b of the mounting seat 38 to fix the airbag device 4 to the steering wheel body 2. The wheel 1 is constructed.

In the case of a car collision or the like, the airbag device 4 is activated to deploy the airbag in front of the occupant and restrain the occupant thrown to the front side to reduce the impact. In addition, regardless of the operation of the airbag device 4,
When the occupant collides with the steering wheel 1, the cored bar 11 deforms, that is, self-aligns, and absorbs the impact. At this time, in the core metal 11, the outer peripheral portion of the boss core metal portion 16 is reinforced by the connecting portions 33c and 53c, and the rim core metal portion 15 and the spoke core metal portion 17 continuous with the connecting portions 33c and 53c. Has a closed tubular shape, and the enclosing connection structure has a rib structure, which has high strength. Further, the outer connection portion 18 where the rim cored bar portion 15 and the spoke cored bar portion 17 are connected to each other, a spoke cored bar large diameter portion 67 and a rim cored bar large diameter portion 68 having an enlarged cross-sectional area are formed. In addition, since the large diameter portion 67 of the spoke core metal has a smooth fan shape and has an enlarged cross-sectional area, it is possible to suppress concentration of stress on the outer connecting portion 18. Therefore, the boss core metal part 16
The peripheral portion of the boss flange portion 23b of the boss body 23 becomes a weak portion to concentrate the deformation, and while maintaining the overall shape of the steering wheel body 2 against an external force, the so-called root portion of the spoke core bar portion 17 The angle changes to absorb the impact, and the impact absorption characteristics are easily improved.

Next, a frequency measuring method for measuring the vibration characteristics of the steering wheel 1 of the present embodiment will be described.

That is, the measuring device 76 used in this experiment
As shown in FIG. 5, the FET analyzer 77 and this F
Power unit electrically connected to ET analyzer 77
It has a 77a and a sensor amplifier 77b. Further, an impulse hammer 78 is mechanically connected to the power unit 77a to drive it forward and backward, and a sensor amplifier 77b.
A pickup 79, which is a sensor, is electrically connected to.

In the measuring device 76, the rim portion 5 of the steering wheel 1 fixed to the steering shaft S is hit with a desired force by the impulse hammer 78, and the pickup 79 attached to the rim portion 5 of the steering wheel 1 is used. The vibration generated in the steering wheel 1 is detected by. Then, the detected vibration is input to the FET analyzer 77 via the sensor amplifier 77b, and the analyzed waveform of the vibration characteristic is output.

Steering wheel 1 used in this experiment
In the above embodiment, the upper and lower shells 21 and 22 forming the cored bar 11 are press-formed steel plates with a thickness of 1.0 mm, the boss 23 is forged, and the vibration damping unit W is The mass of the cored bar 11 including it is less than about 1 kg. It should be noted that this mass corresponds to the mass of a core bar made of a magnesium alloy in which a dynamic damper, which is a conventional vibration damping device, is combined.

A graph of the characteristics obtained by this experiment is shown in FIG. The vertical axis of this graph is inertance (acceleration / force), and the horizontal axis is frequency. And
The line P is the characteristic of the steering wheel 1 of the present embodiment,
Line Q is the steering wheel that does not include damping structure, line R
Is a characteristic of a conventional dynamic damper attached to the boss. The first peak f1 on the horizontal axis is about 3
The second peak f2 at 0 Hz corresponds to about 90 Hz. In addition,
The resonance point of a passenger car during idling varies depending on the individual vehicle, but is usually in the range of 20 Hz to 40 Hz, and the resonance point during high-speed traveling is about 100 Hz.

In this experiment, it was shown that the steering wheel 1 of the present embodiment can suppress the vibration with respect to any peak value of the vibration assuming idling and high speed running, as compared with other configurations.

The function of suppressing the vibration is that the fluid L filled in each compartment C of the vibration damping unit W provided in the vibration damping unit housing B of the core metal 11 causes the vibration or movement of the core metal 11. It is considered that this is because the fluid L moves a little later and comes into contact with the inner wall of the compartment C, that is, the fluid L reciprocates slightly behind the reciprocating movement in the vibration of the cored bar 11 to prevent the fluid L from moving in the vibration direction.

As described above, according to the steering wheel 1 of the present embodiment, when the steering wheel 1 vibrates, the fluid L that is enclosed in the container W1 and occupies a part of the container W1 moves, By colliding with the inner wall portion of the portion W1, the vibration damping unit W vibrates in a phase different from that of the other portions, resonance is suppressed, and vibration characteristics are efficiently adjusted, so that the operational feeling can be improved. That is, the steering wheel 1
It is possible to effectively suppress the vibration that occurs in the steering wheel 1, to make the vibration characteristic of the steering wheel 1 flat without having a resonance point at a specific frequency, and to secure a wide frequency band of such a characteristic. The operation feeling of the steering wheel 1 can be improved. In other words, since each compartment C of the container portion W1 of the vibration damping unit W is filled with the fluid L, the fluid L can move in each compartment C of the container portion W1 and the steering is performed. Wheel 1
The fluid L is moved by the vibration of the above and collides with the inside of the container W1, and the resonance can be suppressed by the phase difference between the vibration of the steering wheel 1 and the collision of the fluid L.

Further, since the vibration damping unit W uses the fluid L, the degree of freedom in the shape of the vibration damping unit W having the container portion W1 is improved as compared with the structure using the metal block as the weight. It is possible to improve versatility. That is,
Since the fluid L can be freely deformed according to the shape of the container, it can be applied to a complicated container shape. Therefore, the limited space of the rim portion 5 of the steering wheel 1 can be used, and further, the vibration can be suppressed at a position separated from the boss portion 6 which is the mounting portion of the steering wheel 1, and the vibration can be effectively suppressed.

Further, the vibration damping unit W has a large degree of freedom in shape and can be easily arranged along the rim cored bar portion 15. Rim core metal part
By mounting along the line 15, the space of the rim portion 5 of the steering wheel 1 can be effectively utilized to mount the vibration damping unit W.

Further, since the vibration damping unit W uses the fluid L, it is possible to easily suppress the collision sound with the container W1 as compared with the structure in which a metal block or the like is used as a weight, and a special noise countermeasure is taken. It is not necessary to simplify the structure.

In addition, as described above, this damping unit W
The vibration characteristics can be adjusted efficiently, and the weight of the vibration damping unit W itself can be reduced. The steering wheel 1 using the vibration damping unit W is lighter than the configuration using the metal block or the like as the weight. Therefore, the rotational moment of the steering wheel 1 can be suppressed, and the operational feeling of the steering wheel 1 can be improved.

The rim cored bar portion 15 includes the upper and lower shells 21,
It is a shell structure composed of 22, and these shells 21 and 22
By overlapping and joining the vibration damping units W, the vibration damping unit housing B capable of housing and fixing the vibration damping unit W can be formed in the hollow portion A, so that the limited space of the rim portion 5 can be used more effectively. The unit W can be arranged, the manufacturing process of the steering wheel 1 can be simplified, and the manufacturing cost can be reduced.

Further, the container portion W1 of the vibration damping unit W is provided with a plurality of compartments C which can be filled with the fluid L and are partitioned from each other. At least one of these compartments C and an appropriate single Alternatively, by enclosing the fluid L in the plurality of compartments C, desired vibration characteristics can be easily realized. That is, a predetermined amount of fluid can be secured at a predetermined location of the vibration damping unit W arranged on the rim portion 5, and vibration damping characteristics can be effectively and stably secured. Further, it is also possible to appropriately adjust the vibration damping characteristics between the two adjacent compartments C, for example, to make the vibration damping characteristics match or to set them to be different from each other.

In addition, in the structure in which the branch chamber C is provided in this way, it is possible to easily set the fluid L to be moved in a relatively small range (span), and it is possible to easily improve the damping characteristic for a relatively high vibration frequency. .

Further, since the compartments C are formed so as to be arranged side by side in the circumferential direction of the rim cored bar portion 15, it is possible to suppress the fluid L from moving a long distance in the circumferential direction. Therefore, when the rim portion 5 of the steering wheel 1 is rotationally operated, the time difference of the generation of the moment can be made extremely small, and the deterioration of the operability due to the provision of the vibration suppressing means can be easily prevented,
The operability can be easily improved.

Further, since the vibration damping unit W is disposed inside the rim cored bar portion 15 of the shell structure, it does not affect the shape of the rim portion 5 which is the grip portion, and for example, the upper and lower rim covers 71 are provided. , 72 is not required to be changed, and the steering wheel 1 having excellent tactile sensation, operability and design can be easily realized.

Further, as in the above-described embodiment, with the steering wheel 1 attached to the steering shaft S, the connecting portion between the spoke portion 7 and the rim portion 5 is located at the lower side in the circumferential direction of the rim portion 5. Is unevenly distributed in the rim portion 5
In the steering wheel 1 which can secure a space for meter viewing on the upper side in the circumferential direction, the vibration damping unit W is disposed on the upper side in the circumferential direction of the rim portion 5, so that a flatter frequency band than that in the past can be obtained. Vibration characteristics are obtained,
An unpleasant resonance can be suppressed with respect to an input from a normal engine or running, and a good visibility can be achieved at the same time with a configuration capable of improving the operational feeling.

Further, in the vibration damping structure of the present embodiment, only the vibration damping unit adapted to the shape of various rim cored bar portions is set, and basically the outer shape of the rim portion is not constrained. It is possible to flexibly respond to the usage conditions of and improve the versatility.

The fluid L occupies a part of each of the compartments C of the container W1 and is enclosed, and the rest is a space. In this space, the fluid to be enclosed and the conditions of vibration are taken into consideration. Therefore, the pressure can be set appropriately. For example, the pressure may be atmospheric pressure, or the pressure may be reduced or increased.
Further, this space can be filled with air, or the air can be replaced with an inert gas such as nitrogen.

As a method of filling the fluid L such as silicone oil, a predetermined amount is dispensed in advance into each of the compartments C of the container body W1a of the container W1 and then covered with the lid W1b.
Various methods can be adopted. For example, arrow I in FIG.
As shown in the section, after covering the container body W1a with the lid W1b, the lid L is filled with the fluid L from the dispensing port 81 previously formed in the lid W1b using the jig 82, and then the arrow II part As shown in, the mouth 81 can be closed by heating. Further, the dispensing port (dispensing port) 81 may be closed by a closing means such as a rubber stopper. For example, as shown by an arrow III in FIG. It is also possible to provide a mouth 81 and seal it with a closing means 84 such as a rubber stopper, and the arrow in FIG.
As shown in section IV, the partition walls of two adjacent compartments C
It is also possible to form the opening 81 over 85 and close the opening 81 with the closing means 86 such as a rubber stopper to reduce the number of parts and the manufacturing cost.

Incidentally, FIG. 7 shows a seal member 88 which is fitted between the container body W1a and the lid W1b and holds the adjacent compartments C or the compartment C and the outside in an airtight manner. Has been done.

Further, the amount of the fluid L such as silicone oil, that is, the height of the liquid surface in each compartment C does not have to be constant, and the volume of each compartment C can be appropriately determined.

Further, the structure of the cored bar 11 is not limited to the one in which the upper and lower shells 21 and 22 are press-molded as described above, and an appropriate structure such as a synthetic resin can be adopted.

For example, as shown in FIG. 8, at least the rim core metal part 15 of the core metal 11 is die-cast into a substantially U-shaped cross section with a magnesium alloy, and the vibration damping unit W is provided along the rim core metal part 15. Can also be stored.

Furthermore, in the embodiment shown in FIG.
With the vibration damping unit W combined with the rim core metal part 15,
The covering portion 91 made of polyurethane resin is formed integrally with the rim core metal portion 15 by injection reaction formation so that the vibration damping unit W can be embedded in the rim portion 5.

Further, in each of the above-described embodiments, a plurality of vibration damping units W can be provided in the rim portion 5, or can be arranged in a place other than the rim portion 5. Further, in addition to the vibration damping unit W, a vibration damping device including a weight may be arranged on the boss portion 6.

The configuration of the steering wheel 1 is as follows.
The present invention is not limited to the above, and for example, the spoke portion 7, that is, the spoke core metal portion 17 may have one of three, three, four, or more. Further, the covering portion 12 for covering the cored bar 11 is provided with a member formed in advance, in addition to the cored bar.
It is also possible to insert resin by injecting resin with 11 being attached to the mold.

[0083]

According to the steering wheel of the first aspect, when the steering wheel vibrates, the fluid moves in the container part and collides with the inner wall part of the container part, so that the vibration suppressing means is provided in another part. It vibrates in a different phase, resonance is suppressed, vibration characteristics are adjusted efficiently, and a feeling of operation can be improved. By using the fluid, it is possible to improve the degree of freedom of the shape of the vibration suppressing unit including the container portion and improve versatility. Further, by using the fluid, it becomes easy to suppress the collision noise and the structure can be simplified. Since the vibration characteristics can be adjusted efficiently, the vibration suppressing means can be lightened, the rotational moment can be suppressed, and the operational feeling can be improved.

According to the steering wheel of the second aspect, in addition to the effect of the first aspect, the rim core metal portion has a substantially annular shape, and the vibration suppressing means has a substantially arc shape along the rim core metal portion. Therefore, the vibration suppressing means can be provided by effectively utilizing the space of the rim portion of the steering wheel.

According to the steering wheel of the third aspect, in addition to the effect of the first or second aspect, the rim cored bar portion includes a first half shell provided with a first rim cored bar portion constituting section,
A second half shell provided with a second rim core metal part forming part, and a first rim core bar part forming part and a second rim in a state in which the first half shell and the second half shell are superposed on each other. Since the vibration suppressing means is housed in the hollow portion and includes the hollow portion formed between the core metal portion constituting portion, the vibration suppressing means can be provided by effectively utilizing the space of the rim portion of the steering wheel. .

According to the steering wheel of the fourth aspect, in addition to the effect of any one of the first to third aspects, the container portion of the vibration suppressing means is provided with a plurality of compartments that are partitioned from each other and capable of enclosing a fluid. Therefore, for a plurality of compartments, a desired vibration characteristic can be realized by enclosing the fluid in an appropriate single or a plurality of compartments. Also, it is easy to move the fluid in a relatively small range,
It is possible to easily improve the damping characteristic for a relatively high vibration frequency.

According to the steering wheel of the fifth aspect, in addition to the effect of the second or third aspect, the container portions of the vibration suppressing means are each capable of enclosing a fluid and arranged side by side in the circumferential direction of the rim cored bar portion. Since the plurality of partitioned chambers are provided, desired vibration characteristics can be realized by enclosing a fluid in an appropriate single or a plurality of partitioned chambers. In addition, the fluid can be easily moved within a relatively small range, and the damping characteristics for a relatively high vibration frequency can be easily improved. Furthermore, since the fluid does not move a long distance in the circumferential direction, the time difference in the generation of the moment when the rim portion of the steering wheel is rotated is reduced, and the operability can be improved.

[Brief description of drawings]

FIG. 1 is a partial exploded perspective view showing an embodiment of a steering wheel of the present invention.

FIG. 2 is an exploded perspective view with a part cut away showing the steering wheel.

FIG. 3 is a partially cutaway perspective view showing the same steering wheel.

FIG. 4 is an explanatory view showing a vibration suppressing means of the steering wheel of the above. (a) is a sectional view (b) is a partially enlarged sectional view of (a)

FIG. 5 is an explanatory diagram showing a method for measuring the vibration characteristic of the steering wheel of the above.

FIG. 6 is a graph showing vibration characteristics of the steering wheel of the above.

FIG. 7 is an explanatory diagram showing another embodiment of the vibration suppressing means for the steering wheel of the present invention.

FIG. 8 is a partially cutaway perspective view showing still another embodiment of the steering wheel of the present invention.

[Explanation of symbols]

1 steering wheel 11 core metal 15 Rim core metal part 16 Boss core 17 Spoke core bar 21 Upper shell as the first half shell 22 Lower shell as second half shell 31 Top of rim as first rim core metal part 51 Lower rim as second rim core metal part A hollow part C branch L fluid S Steering shaft as steering shaft W Vibration suppression unit as vibration suppression means W1 container

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Izumi Sato             218 Aoshima-cho, Fuji City, Shizuoka Prefecture Japan Plus             Inside the corporation (72) Inventor Shinya Suzuki             218 Aoshima-cho, Fuji City, Shizuoka Prefecture Japan Plus             Inside the corporation F-term (reference) 3D030 CA09 DA44

Claims (5)

[Claims] 1. A rim mandrel for gripping operation, a boss mandrel connected to a steering shaft, and a spoke mandrel connecting the boss mandrel and the rim mandrel. A cored bar, and a vibration suppressing means provided along at least a part of the rim cored bar and having a sealed container part and a fluid movably sealed in the container part. And steering wheel. 2. The steering wheel according to claim 1, wherein the rim cored bar portion has a substantially annular shape, and the vibration suppressing means has a substantially arcuate shape along the rim cored bar portion. 3. The rim cored bar portion includes a first half shell including a first rim cored bar portion forming portion, a second half shell including a second rim cored bar portion forming portion, and these first half shells. And a hollow part formed between the first rim core metal part forming part and the second rim core metal part forming part in a state in which the half shell and the second half shell are superposed, The steering wheel according to claim 1 or 2, wherein the suppressing means is housed in the hollow portion. 4. The steering wheel according to claim 1, wherein the container portion of the vibration suppressing means is provided with a plurality of compartments that are partitioned from each other and that can contain a fluid. 5. The container of the vibration suppressing means is provided with a plurality of compartments which are capable of enclosing a fluid and are partitioned and arranged side by side in the circumferential direction of the rim cored bar. Steering wheel.