JP4852063B2 - Steering wheel vibration reduction structure - Google Patents

Description

  The present invention relates to a vibration reduction structure for a steering wheel that reduces vibration in a direction perpendicular to the axis of the steering wheel by using an airbag module supported inside the steering wheel as a mass.

The airbag module is elastically supported via a coil spring inside the steering wheel, and the driver presses the steering wheel pad to compress the coil spring in the axial direction to operate the horn switch. Japanese Patent Application Laid-Open No. 2004-151867 discloses that the inflator is supported by an elastic body different from the coil spring and functions as a dynamic damper.
JP 2006-96127 A

  By the way, if the common coil spring is also used for a horn switch and a dynamic damper, it becomes difficult to tune the spring constant of the coil spring, the horn switch malfunctions, and the vibration damping performance of the dynamic damper is not fully demonstrated. There is a problem to do. Further, when separate spring members are used for the horn switch and the dynamic damper as in the invention described in Patent Document 1, there is a problem that the number of parts increases.

  The present invention has been made in view of the above circumstances, and an object thereof is to effectively reduce the vibration of the steering wheel without affecting the operability of the horn switch and without increasing the number of parts. .

In order to achieve the above object, according to the first aspect of the present invention, guide means for guiding the airbag module in the steering wheel so as to be movable in the axial direction of the steering shaft and in the direction perpendicular to the axis of the shaft. When the air bag module for independently provided a stopper means having the elastic member to the steering wheel may abut so as to restrict the movable range of the axis perpendicular direction of the steering wheel to one another Rutotomoni, the guide means, said has a coil spring for elastically supporting said axially the air bag module is provided in a compressed state between the steering wheel and the airbag module, wherein the airbag module while deforming the coil spring Press in the axial direction to activate the horn switch With the amplitude of vibration in the axial perpendicular direction of the steering wheel relative to the air bag module only when it is above a predetermined value, the direction perpendicular to the axis the elastic body of the stopper means to said air bag module of the steering wheel The movement limit in the direction perpendicular to the axis of the steering wheel is restricted by the stopper means before being restricted by the guide means, and at least one of the stopper means is configured such that the steering wheel is neutral. when in the position, the vibration reduction structure of the steering wheel, characterized in that arranged in a vertical plane passing through the center of gravity of the air bag module Ru it has been proposed.

According to the present invention , the guide means for guiding the airbag module to be movable in the axial direction and the direction perpendicular to the steering shaft inside the steering wheel, and the movable range in the direction perpendicular to the axis of the steering wheel with respect to the airbag module are provided. Rutotomoni provided a stopper means having a resilient body which can contact with the steering wheel so as to regulate independently of each other, the guide means, the axial direction of the air bag module is provided in a compressed state between the steering wheel and air bag module Since the coil spring is elastically supported, the horn switch can be operated by pressing the airbag module in the axial direction while deforming the coil spring, and the steering wheel for the airbag module. Direction perpendicular to the axis When the amplitude of the vibration exceeds a predetermined value, by elastic stopper means for restricting the relative movement of the axis-perpendicular direction relative to the air bag module of the steering wheel, the airbag module to attempt to continue stopped by inertia mass in can reduce vibration of the steering wheel, which makes it possible to reduce the number of parts, also it is not necessary to share the elastic body stopper means the elastic body of the horn switch (ie the coil springs) Therefore, the setting of the operating characteristics of the horn switch is facilitated, and the occurrence of malfunction can be prevented.

Transverse movement limit of the or scan tearing wheel, because it is restricted by the stopper means before being restricted by the guide means, ensuring anti-vibration performance reliably actuate the stopper means without being obstructed by the guide means can do.

In addition, at least one of the stopper means is placed in a vertical plane that passes through the center of gravity of the airbag module when the steering wheel is in the neutral position, so that the most frequent vertical vibration of the steering wheel occurs. In this case, when the vibration of the steering wheel is transmitted to the airbag module through the stopper means arranged in the vertical plane, the vibration in the direction in which the steering wheel is rotated is prevented from being generated. Performance can be increased.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 7 show a first embodiment of the present invention. FIG. 1 is a perspective view of a steering wheel of an automobile, and FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG. 3 is an enlarged cross-sectional view taken along line 3-3 in FIG. 1 (cross-sectional view taken along line 3-3 in FIG. 4), FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. 2, and FIG. FIG. 6 is an operation explanatory diagram when the horn is operated, and FIG. 7 is an operation explanatory diagram when the steering wheel vibrates left and right.

  As shown in FIGS. 1 to 3, the steering wheel 11 of the automobile is formed of a disk-shaped metal plate that is spline-fitted to the rear end of the steering shaft 12 that extends downward from the passenger compartment to the front of the vehicle body and is fastened by a nut 13. A boss member 14 is provided, and a container-like cover member 15 whose rear surface is open is fixed so as to cover the front surface of the boss member 14. Four spoke portions 15a ... are integrally extended radially outward from the outer peripheral portion of the cover member 15, and an annular rim portion 15b is integrally formed at the tip thereof. A metal ring 16 for reinforcement is embedded in the rim portion 15b. The rear surfaces of the four spoke portions 15a are covered with spoke portion covers 17, respectively, and a steering pad 18 is disposed radially inward of the spoke portion covers 17. The center of a holder 19 made of a metal plate is fastened to the rear surface of the boss member 14, and the airbag module 20 is supported by the holder 19 via three guide means 21, left, right and lower. .

  In this specification, the axial direction (front-rear direction) is defined as the longitudinal direction of the steering shaft 12, and the direction perpendicular to the axis (up-down direction or left-right direction) is defined as a direction orthogonal to the longitudinal direction of the steering shaft 12. The

The structure of the three guide means 21... For supporting the airbag module 20 on the holder 19 is the same. 2 shows two guide means 21 and 21 on the left and right sides of the steering shaft 12, and FIG. 3 shows one guide means 21 on the lower side of the steering shaft 12. All three guide means 21 are shown in FIG.
As is apparent from FIG. 5, each guide means 21 includes a guide shaft 23 that slidably passes through a guide plate 22 provided in the holder 19 from the rear to the front and is prevented from being removed by a stopper projection 23a. Disc-shaped first and second flanges 23 b and 23 c are provided in parallel at the rear portion of the guide shaft 23, and are arranged on the outer periphery of the guide shaft 23 between the front first flange 23 b and the rear surface of the holder 19. The coil spring 24 to be fitted is contracted.

  A center hole 25a of an annular guide ring 25 is fitted to the outer periphery of the guide shaft 23 between the first and second flanges 23b and 23c so as to be movable in the direction perpendicular to the axis, and is formed on the outer periphery of the guide ring 25. The mounting hole 27a of the bracket 27 made of a metal plate is fitted into the groove 25b. The number of brackets 27 is one, and the brackets 27 are supported by the holder 19 by three guide means 21.

  The airbag module 20 includes an inflator 28 that generates high-pressure gas, and an airbag 29 that is arranged in a folded state behind the inflator 28, a flange 28 a provided on the outer periphery of the inflator 28, and a first The retainer 30, the open end of the airbag 29, and the second retainer 31 are overlapped with an opening 27 b formed at the center of the bracket 27 and fastened together with bolts 32 and nuts 33.

  A connecting portion 18 a extending forward from the outer peripheral portion of the steering pad 18 is fixed to the outer peripheral portion of the bracket 27 with bolts 34 and nuts 35. In this state, the steering pad 18 is disposed behind the folded airbag 29. Covering. The three movable contacts 36a provided forward on the outer peripheral portion of the bracket 27 are opposed to the three fixed contacts 36b provided rearward on the outer peripheral surface of the holder 19, respectively. These movable contacts 36a and fixed contacts 36b constitute horn switches 37.

  As is apparent from FIGS. 2 to 5, three stopper means 38... Are provided between the tip of the arm portion 18 b extending in the direction perpendicular to the axis from the coupling portion 18 a of the steering pad 18 and the inner surface of the opening of the cover member 15. Provided. As is apparent from FIG. 4, the three stopper means 38 are arranged radially outside the three guide means 21 with the steering shaft 12 as the center, and their structures are all the same.

  That is, the stopper means 38 protrudes forward from the tip of the arm portion 18 b of the steering pad 18, for example, a stopper pin 39 made of hard rubber and formed in a cylindrical shape, and a cylindrical shape formed on the inner surface of the opening of the cover member 15. The diameter of the stopper pin 39 is set smaller than the diameter of the recess 15c.

  As is clear from FIG. 4, the airbag module 20 floatingly supported on the holder 19 by the three guide means 21... Is moved downward by gravity, and the stopper pins 39 of the stopper means 38. It stops at the position where it abuts on the lower end. At this time, a gap α exists between the guide shafts 23 of the guide means 21 and the lower ends of the center holes 25a of the guide rings 25. Therefore, when the cover member 15 and the holder 19 move relative to the airbag module 20 in the direction perpendicular to the axis, the movable range is limited to the range in which the stopper pins 39 of the stopper means 38 move within the recesses 15c. Is done. When the stopper pins 39 of the stopper means 38 move within the recesses 15c, the guide shaft 23 does not contact the inner peripheral surface of the center hole 25a of the guide ring 25 of the guide means 21, and the α A larger gap is secured.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  As shown in FIG. 6, when the right part, the left part or the lower part of the steering pad 18 of the steering wheel 11 is pushed to operate a horn (not shown), the steering pad 18 is supported by a bracket 27 connected to the airbag module 20. One of the three guide shafts 23... Is guided by a guide plate 22 provided on the holder 19 and advances while compressing the coil spring 24, and a movable contact 36 a provided on the bracket 27 is provided on the holder 19. By contacting the fixed contact 36b, the horn can be conducted to the battery and ringed.

  By the way, when the vibration of the engine or the vibration from the road surface is transmitted to the steering wheel 11 via the steering shaft 12, the driver's hand holding the steering wheel 11 vibrates and gives unpleasant feeling. The vibration in the direction perpendicular to the axis of the steering wheel 11 is suppressed using the mass.

  That is, when the steering wheel 11 vibrates in the direction perpendicular to the axis, the cover member 15 integrated with the steering wheel 11 also vibrates in the direction perpendicular to the axis. Since there is a sufficient gap between the recess 15c of the cover member 15 and the stopper pin 39 of the stopper means 38, vibration in the direction perpendicular to the axis of the steering wheel 11 is transmitted to the airbag module 20. Absent. The guide shafts 23 of the three guide means 21 provided in the holder 19 integrated with the steering wheel 11 also vibrate in the direction perpendicular to the axis, but between the guide shafts 23 and the central holes 25a of the guide rings 25. Since there is a sufficient gap, vibration in the direction perpendicular to the axis of the steering wheel 11 is not transmitted to the airbag module 20.

  When the amplitude of the vibration further increases, the three stopper means 38 actuate and the vibration of the steering wheel 11 is transmitted to the airbag module 20. That is, the stopper pins 39 provided on the steering pad 18 integral with the airbag module 20 abut on the inner peripheral surface of the recesses 15 c provided on the cover member 15 integral with the steering wheel 11, Then, the steering wheel 11 is integrated so as not to move further. Thus, when the steering wheel 11 vibrates greatly, the steering wheel is brought into contact with the airbag module 20 which has a relatively large mass and is intended to maintain a stopped state with inertia through the stopper means 38. 11 vibrations in the direction perpendicular to the axis can be suppressed by the mass of the airbag module 20.

  FIG. 3 corresponds to a state in which the steering wheel 11 vibrates upward and the lower end of the recess 15 c of the stopper means 38 abuts against the stopper pin 39. 7 corresponds to a state in which the steering wheel 11 vibrates rightward and the left end of the recess 15c of the stopper means 38 abuts against the stopper pin 39.

  As described above, even if the steering wheel 11 vibrates in the direction perpendicular to the axis, the vibration is absorbed by the sliding of the guide ring 25 in the direction perpendicular to the axis of the guide ring 23 with respect to the first and second flanges 23b and 23c of the guide means 21. Therefore, there is no possibility that the guide shaft 23 may slide in the axial direction while compressing the coil spring 24 to cause the horn switch 37 to malfunction.

Further, among the vibrations in the direction perpendicular to the axis of the steering wheel 11, the vibration in the vertical direction tends to be strongest. When the steering wheel 11 is in the neutral position (see FIGS. 1 and 4), at least one stopper means 38 positioned on the lower side is disposed in a vertical plane passing through the center of gravity of the airbag module 20, In addition, since the left and right two stopper means 38, 38 are also arranged symmetrically with respect to the vertical plane, a moment around the axis is generated by the reaction load that the steering wheel 11 receives from the airbag module 20. And vibration of the steering wheel 11 can be more effectively suppressed.

  Further, since the stopper pins 39 are made of an elastic body such as hard rubber, it is possible to reduce noise when the stopper pins 39 abut against the inner peripheral surface of the recess 15c of the cover member 15.

  Furthermore, when vibration in the direction perpendicular to the axis is input to the steering wheel 11, the coil spring 24 that expands and contracts in the axial direction is not affected, so the spring constant of the coil spring 24 is composed of the movable contact 36a ... and the fixed contact 36b ... What is necessary is just to set so that the malfunctioning by the vibration of horn switch 37 ... vibration and operation feeling may be satisfy | filled, and the design freedom improves significantly.

According Thus to the present embodiment, the prior art as compared to those respective horn switch and a dynamic damper as in (Patent Document 1), using separate spring member, it is possible to reduce the number of parts, also a stopper Since it is not necessary to share the elastic body (that is, the stopper pin 39) of the means 38 with the coil spring 24 of the horn switch 37, it is easy to set the operating characteristics of the horn switch 37 and prevent the occurrence of malfunction. it can.

  Further, since the limit of movement of the airbag module 20 in the direction perpendicular to the axis is restricted by the stopper means 38 before being restricted by the guide means 21, the stopper means 38 can be securely moved without being obstructed by the guide means 21. It can be actuated to ensure anti-vibration performance.

  8 and 9 show a second embodiment of the present invention. FIG. 8 is a view corresponding to FIG. 5, and FIG. 9 is an enlarged sectional view taken along line 9-9 of FIG.

  In the second embodiment, the structure of the guide means 21 is different from that of the first embodiment, and other structures are the same as those of the first embodiment.

  The guide means 21 of the second embodiment is provided with a pair of parallel guide plates 40, 40 provided in parallel to the rear surface of the bracket 27 and extending in the left-right direction. A guide pin 41 fixed so as to penetrate the rear part of the guide shaft 23 in the vertical direction penetrates the long holes 40a, 40a formed in the slidably. The coil spring 24 is contracted between the rear surface of the holder 19 and the front surface of the bracket 27, and the guide shaft 23 loosely penetrates the opening 27 c formed in the bracket 27.

  Also according to the second embodiment, the three air guide modules 21 are supported by the three guide means 21 so as to be movable in the direction perpendicular to the axis including the vertical direction and the horizontal direction, and the coil spring is operated to operate the horn switch 37. The airbag module 20 can be moved in the axial direction while compressing 24.

  Also according to the second embodiment, it is possible to achieve the same operational effects as those of the first embodiment described above.

  Next, a third embodiment of the present invention will be described with reference to FIG.

  In the first and second embodiments described above, the guide means 21 and the coil spring 24 are provided together. However, in the third embodiment, the guide means 21 and the coil spring 24 are separated from each other. Is provided.

  That is, the spring guide 43 having one end fixed to the connecting plate 42 is slidably passed through the bracket 27 and is prevented from coming off by a flange 43 a provided at the other end, and the coil spring 24 disposed on the outer periphery of the spring guide 43. Is contracted between the connecting plate 42 and the bracket 27. One end of a guide shaft 44 is fixed to the connecting plate 42, and is sandwiched between a disc-shaped flange 44a integrally formed in the vicinity of the tip thereof and a disc-like flange 44b screwed to the tip. The portion is slidably fitted into an opening 15d formed in the cover member 15.

  Therefore, when the steering pad 18 of the steering wheel 11 is pushed, the bracket 27 connecting the steering pad 18 to the airbag module 20 moves forward along the spring guide 43 while compressing the coil spring 24, and the horn switch 37 is activated. To make the horn ring.

  When the steering wheel 11 vibrates in the direction perpendicular to the axis due to the vibration of the engine or the road surface, the cover member 15 integrated with the steering wheel 11 also vibrates in the direction perpendicular to the axis, but the recess 15c of the cover member 15 and the stopper of the stopper means 38 Since there is a sufficient gap between the pins 39, vibration in the direction perpendicular to the axis of the steering wheel 11 is not transmitted to the airbag module 20. Even when the cover member 15 integrated with the steering wheel 11 vibrates in the direction perpendicular to the axis, a sufficient gap is provided between the guide shaft 44 sandwiched between the pair of flanges 44a and 44b and the edge of the opening 15d of the cover member 15. Therefore, vibration in the direction perpendicular to the axis of the steering wheel 11 is not transmitted to the airbag module 20.

  When the amplitude of the vibration further increases, the three stopper means 38 are operated, and the stopper pin 39 provided on the steering pad 18 integral with the airbag module 20 is applied to the inner peripheral surface of the recess 15c provided on the cover member 15. The vibration of the steering wheel 11 in the direction perpendicular to the axis can be suppressed by the mass of the airbag module 20 by integrating the steering wheel 11 so as not to move further relative to the airbag module 20.

  According to the third embodiment, in addition to the operational effects of the first and second embodiments, the guide means 21 and the coil spring 24 are provided separately to improve the design freedom, Moreover, since the flange 44b can be attached to and detached from the guide shaft 44 with a screw, it is possible to achieve a further effect that the assembly of the guide shaft 44 to the opening 15d of the cover member 15 becomes easy.

  Next, a fourth embodiment of the present invention will be described based on FIG. 11 and FIG.

  The fourth embodiment is a modification of the third embodiment, and only the structure of the guide means 21 is different from the third embodiment.

  That is, a long hole 45a extending in the vertical direction is formed in the guide plate 45 fixed to the connecting plate 42, and the distal end of the guide pin 46 having a head 46a at the base end and penetrating the long hole 45a is a boss. Screwed to a bracket 47 fixed to the member 14. Therefore, when the guide pin 46 slides in the longitudinal direction with respect to the long hole 45a of the guide plate 45, the steering wheel 11 can be moved relative to the airbag module 20 in the left-right direction. By sliding the guide pin 46 along the longitudinal direction of 45a, the steering wheel 11 can be moved relative to the airbag module 20 in the vertical direction.

  According to the fourth embodiment, the guide means 21 and the coil spring 24 are provided separately, so that the degree of freedom in design is improved and the guide means 46 is simply attached to and detached from the bracket 47. Since 21 can be assembled and disassembled, the same effect as the third embodiment can be achieved.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, three guide means 21, three stopper means 38, and three horn switches 37 are provided. However, the number thereof is not limited to the embodiment.

  In the second and fourth embodiments, the direction of the long holes 40a and 45a of the guide plates 40 and 45 and the direction of the guide pins 41 and 46 are limited to those of the embodiment as long as they are orthogonal to each other. It is not something.

The perspective view of the steering wheel in the neutral position of the motor vehicle which concerns on 1st Embodiment 2-2 line enlarged sectional view of FIG. 1 (2-2 line sectional view of FIG. 4) 3-3 enlarged sectional view of FIG. 1 (3-3 sectional view of FIG. 4) Sectional view along line 4-4 in FIG. 5 enlarged view of FIG. Action explanation diagram at the time of horn operation Action explanatory diagram at the time of left and right vibration of the steering wheel The figure corresponding to the said FIG. 5 which concerns on 2nd Embodiment. FIG. 9 is an enlarged cross-sectional view taken along line 9-9. The figure corresponding to the said FIG. 2 which concerns on 3rd Embodiment The figure corresponding to the said FIG. 2 which concerns on 4th Embodiment 12-12 enlarged sectional view of FIG.

11 steering wheel 20 the air bag module 21 guide means 24 coils scan purine grayed 37 horn switch 38 stopper means
39 Stopper pin as an elastic body

Claims (1)

Inside the steering wheel (11), guide means (21) for guiding the airbag module (20) to be movable in the axial direction of the steering shaft (12) and the direction perpendicular to the axis of the shaft (12), and the airbag the steering wheel (11) the direction perpendicular to the axis the elastic member may contact with the steering wheel (11) so as to restrict the movable range of the relative module (20) a stop means and (38) having a (39) independently of one another are provided Rutotomoni, said guide means (21), elastically supporting the steering wheel (11) and said air bag module (20) under compression has been the air bag module during (20) in the axial direction A coil spring (24)
Actuates the horn switch (37) the air bag module while deforming the coil spring (24) (20) is pressed in the axial direction, wherein the steering wheel with respect to the air bag module (20) (11) only when the amplitude of oscillation of the direction perpendicular to the axis exceeds a predetermined value, said shaft the relative air bag module (20) of said elastic member stopper means (38) (39) is the steering wheel (11) Regulates the relative movement in the right angle direction ,
The movement limit in the direction perpendicular to the axis of the steering wheel (11) is restricted by the stopper means (38) before being restricted by the guide means (21),
At least one of the stopper means (38) is arranged in a vertical plane passing through the center of gravity of the airbag module (20) when the steering wheel (11) is in a neutral position. , vibration reduction structure of the steering wheel.

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