JP2006076381A - Steering wheel equipped with airbag device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an operation part provided on a peripheral side of a pad part from being broken and flying to an occupant side in a steering wheel equipped with an airbag cushion for expanding/developing from the pad part to be a donut shape at the time of collision of a vehicle. <P>SOLUTION: Steering switches 29 are provided on a peripheral side of the steering wheel W of a side part 2b at left/right end parts of the pad part 2. As for the steering switches 29, button part 61 might be formed to be an approximate hat shape in cross section and might be designed so as not to move to the occupant side by abutting its flange 61b to the side part 2b, or a button part 65 having a T-shape in cross section might be arranged in the side part 2b and its occupant side might be covered with a seal part 67. The developing cover part 23 of the pad part 2 might be developed so as to cover the occupant side of the steering switches 29. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a steering wheel provided with an airbag device for protecting an occupant in the event of a vehicle collision, and particularly belongs to the technical field of the structure of an operation portion provided in a pad portion of the steering wheel.

  2. Description of the Related Art Conventionally, there is known a steering wheel provided with an airbag device in order to reduce an impact received by an occupant during a vehicle collision. As described above, when the airbag device is provided on the steering wheel, the airbag device is disposed in the pad portion located near the center of the ring portion of the steering wheel, and when the collision is detected, the airbag cushion is provided. And the cover portion of the pad portion is broken to inflate and deploy the airbag cushion forward of the occupant.

  By the way, in general, the pad portion of the steering wheel is provided with a manufacturer's emblem or the like in the approximate center, but the emblem portion is harder than other parts of the cover portion and is difficult to break. As described above, the structure in which the cover portion of the pad portion is broken to inflate and deploy the airbag cushion is configured such that the cover portion is broken while avoiding the emblem portion.

  Of the cover portion of the pad portion, the portion that is torn and deployed (deployment cover portion) is deployed toward the outer peripheral side of the steering wheel while the center portion of the pad portion approaches the occupant side when viewed from the occupant. Therefore, when the emblem portion is deployed as a part of the deployment cover portion, the emblem portion may contact an occupant approaching the steering wheel.

  Therefore, for example, as disclosed in Patent Document 1, the airbag cushion is disposed in a ring shape in front view so as to avoid the central portion of the pad portion provided with the emblem, and from the central portion of the pad portion. There is known a structure in which fracture grooves are formed radially and only the cover portion around the periphery of the airbag cushion is expanded radially while the airbag cushion is inflated and deployed.

On the other hand, conventionally, various switches are provided in the pad portion of the steering wheel in consideration of the operability of in-vehicle devices such as audio. For example, as disclosed in Patent Document 2, the left and right ends of the pad portion are provided. It is known that a member called an ornament is disposed in the section, and various switches are provided on the ornament.
US Patent Application Publication No. 2002/135163 JP 2001-163225 A

  By the way, in the so-called donut type airbag in which the airbag cushion is inflated and deployed like a ring as in the former conventional example (Patent Document 1), the distance between the airbag cushion and the outer peripheral side of the pad portion is a normal airbag. Therefore, when various switches are provided in the pad portion of the steering wheel as in the conventional example (Patent Document 2), when the airbag cushion is inflated in the pad portion, the deformation generated in the pad portion is applied to the switch. The switch is easily transmitted as an impact, and the switch may be damaged by the impact and scattered to the passenger side.

  The present invention has been made in view of such a point, and an object of the present invention is to provide an operation provided on the pad portion in a steering wheel including an airbag cushion that inflates and deploys from the pad portion into a donut shape in the event of a vehicle collision. It is intended to prevent the operation unit from scattering to the occupant side by devising the configuration of the part and the development part.

  In order to achieve the above object, according to the first solution of the present invention, in the steering wheel provided with the airbag device, the operation portion provided on the pad portion is a component of the operation portion at the initial stage of inflation and deployment of the airbag cushion. It has the structure which suppresses scattering of.

  That is, according to the first aspect of the present invention, the ring portion on the outer peripheral side that is gripped by the vehicle occupant, the pad portion disposed substantially at the center of the ring portion, and the spoke portion that connects the pad portion and the ring portion. And a steering wheel in which an airbag device for inflating and deploying an airbag cushion housed in a ring shape toward the occupant side in a vehicle collision is provided in the pad portion.

  The pad portion is covered with a cover on the occupant side, and is provided around a fixed portion where the cover is not expanded even when the airbag cushion is inflated and deployed, and the airbag cushion is inflated. And a deployment part that is developed by breaking the cover along the fracture groove at the time of deployment, the pad part on the outer peripheral side of the development part is provided with at least an operation part for operating the in-vehicle device, This operation part shall have a scattering suppression structure which suppresses that the component of this operation part is scattered at least to the passenger | crew side at the initial stage of inflation deployment of an airbag cushion.

  With this configuration, at the time of a vehicle collision, the donut-shaped airbag cushion is inflated and deployed toward the outer peripheral side relatively avoiding the central part of the pad part, but the operation part provided on the outer peripheral side of the pad part is In the initial stage of inflation and deployment of the air bag cushion, for example, a component such as a switch is configured to be prevented from scattering toward the occupant, so that the occupant is prevented from receiving an impact due to the scattering of the component. Can do. Here, the initial stage of inflation and deployment of the airbag cushion means that the airbag cushion starts to expand in the pad portion, but the cover on the passenger side of the pad portion is not deployed, that is, the pad portion is the airbag cushion. It means a state of being deformed by the expansion of.

  In the above configuration, the outer peripheral side of the pad portion is provided with an outer edge fixing portion that is adjacent to the deploying portion and is separate from the deploying portion, so that the cover is not deployed even when the airbag cushion is inflated and deployed. It is preferable that the operation part is disposed at a position spaced apart from the development part in the outer edge fixing part (invention of claim 2). As described above, by disposing the operation portion on the outer edge fixing portion provided separately from the deployment portion, it is possible to prevent the impact when the airbag cushion is inflated from being directly transmitted to the operation portion. It is possible to prevent the operation unit from scattering to the passenger side. Furthermore, by providing the operation portion apart from the deployment portion, it is possible to more reliably prevent the operation portion from being damaged by being applied with an impact when the airbag cushion is inflated and being scattered to the occupant side.

  Further, the operation unit includes a push button switch, and the occupant side of the operation unit may be covered with a seat member so that the button part of the push button switch is not exposed to the occupant side. . In this way, even if the operation portion is damaged, the components are prevented from being scattered to the occupant side by the seal portion.

  In addition, the operation portion includes a push button switch, and the button portion of the push button switch has a substantially hat-shaped cross section, and the collar portion is in contact with the cover of the pad portion to restrict movement to the occupant side. (Invention of claim 4). As a result, even if an impact is applied to the operation portion when the airbag cushion is inflated, the operation portion can be reliably prevented from scattering to the occupant side by locking the collar portion of the button portion having a substantially hat-shaped cross section to the cover. can do. Furthermore, it is preferable that the button portion of the push button switch is provided with a reinforcing rib (invention of claim 5). By doing so, the button portion can be made difficult to be damaged by the rib formed on the button portion, and the button portion can be prevented from being damaged or scattered to the occupant side due to an impact when the airbag cushion is inflated. Can do.

  Next, in the second solving means of the present invention, in the steering wheel provided with the airbag device, when the airbag cushion is inflated and deployed, the deployed portion of the pad portion is deployed to cover the passenger side of the operation portion. did.

  Specifically, in the invention of claim 6, a ring portion on the outer peripheral side gripped by a vehicle occupant, a pad portion disposed substantially at the center of the ring portion, and a spoke connecting the pad portion and the ring portion And a steering wheel in which an airbag device for inflating and deploying an airbag cushion accommodated in a ring shape toward the occupant side in the event of a vehicle collision is provided.

  The pad portion is covered with a cover on the occupant side, and is provided around a fixed portion where the cover is not expanded even when the airbag cushion is inflated and deployed, and the airbag cushion is inflated. And a deployment part that is developed by breaking the cover along the fracture groove at the time of deployment, the pad part on the outer peripheral side of the development part is provided with at least an operation part for operating the in-vehicle device, The deployment part is configured to deploy the cover around a hinge part provided on the operation part side and cover the operation part when the airbag cushion is inflated and deployed.

  With this configuration, when the airbag cushion is inflated and deployed at the time of a vehicle collision, the occupant side cover of the deployment portion of the pad portion is deployed so as to cover the occupant side of the operation portion provided on the outer peripheral side of the pad portion. Even when the operation portion is damaged due to the impact when the airbag cushion is inflated and deployed, scattering of the operation portion toward the occupant is reliably prevented by the cover of the deployment portion.

  The deployment portion may be configured such that the cover covering the occupant side starts to break from the fracture groove near the operation portion when the airbag cushion is inflated and deployed (invention of claim 7). As a result, the pressure at the time of inflation of the airbag cushion can be released by breaking the cover and deformation of the pad portion can be suppressed, so that the impact transmitted to the operation portion can be reduced and damage to the operation portion can be prevented. Can be prevented.

  Furthermore, it is preferable that the operation portion is provided in at least one of the left end portion, the right end portion, and the lower end portion of the pad portion (invention of claim 8). In general, the upper end side of the pad portion is narrower than the left end portion, right end portion, and lower end portion, and the space between the pad portion central portion provided with an emblem or the like is narrow, so that it is like a donut airbag In the structure in which the airbag cushion is inflated and deployed while avoiding the center portion of the pad portion, the distance from the airbag cushion becomes narrow, and the impact received by the operating portion when the airbag cushion is inflated is increased. Therefore, the impact received by the operation unit can be reduced by providing the operation unit at any one of the left end, the right end, and the lower end of the pad unit.

  As described above, according to the steering wheel provided with the airbag device according to the present invention, the operation portion provided on the outer peripheral side of the pad portion is configured so that the switch or the like is not scattered at the initial stage of inflation and deployment of the airbag cushion. It is possible to prevent the occupant from receiving an impact due to the scattering of the switch or the like.

  In addition, even if the operation part is damaged by the expansion of the airbag cushion, the cover of the development part of the pad part is deployed so as to cover the operation part around the hinge part provided on the operation part side. The cover reliably prevents scattering to the occupant side.

  Furthermore, by configuring the deployment part so that the occupant-side cover starts to rupture from the vicinity of the operation part, the impact when the airbag cushion is inflated transmitted to the operation part can be effectively reduced. On the other hand, by providing the operation portion at least one of the left end portion, the right end portion, and the lower end portion of the pad portion, the distance from the airbag cushion can be relatively increased. The transmitted impact of the airbag cushion can be reduced more effectively. Thus, by comprising the said expansion | deployment part and an operation part, the damage and scattering of this operation part can be prevented effectively.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

(Embodiment 1)
FIG. 1 shows a schematic structure of a steering wheel W provided with an airbag device according to Embodiment 1 of the present invention. The steering wheel W connects the ring portion 1 on the outer peripheral side for the occupant M to grip, the pad portion 2 disposed substantially at the center of the ring portion 1, and the ring portion 1 and the pad portion 2 4. The spokes 3, 3, 4 and 4 (spoke portions) are arranged in the pad portion 2, and an airbag for inflating and deploying an airbag cushion 51 to the occupant M side at the time of a vehicle collision as shown in FIG. A device 5 is provided. In the case of the present embodiment, the airbag cushion 51 is a so-called donut airbag cushion that inflates and deploys in a ring shape when viewed from the passenger side, as will be described later.

  As shown in FIG. 1, the spokes 3, 3, 4, 4 have a pair of left and right lateral spokes 3, 3 extending in the vehicle width direction from the left and right ends of the upper portion of the pad portion 2, and a lower portion of the pad portion 2. A pair of left and right diagonal spokes 4, 4 extending diagonally downward from the left and right ends of the wheel, and the space between the ring portion 1 and the pad portion 2 of the steering wheel W is vertically partitioned by the lateral spokes 3, 3. In addition, the lower space is further divided into three spaces 42, 42, 43 by the diagonal spokes 4, 4.

  That is, an upper space 41 is defined above the pad portion 2 by the lateral spokes 3, 3, and a left and right space 42, lateral to the pad portion 2 by the lateral spokes 3, 3 and the diagonal spokes 4, 4. 42, a lower space 43 is defined below the pad portion 2 by the diagonal spokes 4, 4. By providing these spaces in the steering wheel W, as shown in FIG. 2, when the occupant M collides with the inflated airbag cushion 51, it becomes a refuge for deformation of the airbag cushion 51, and the impact received by the occupant M Can be effectively reduced.

  On the other hand, the ring portion 1, the pad portion 2, and the spokes 3, 3, 4 and 4 of the steering wheel W are provided with a core metal 10 inside as shown in FIG. The ring portion 1, the pad portion 2, and the spokes 3, 3, 4, and 4 are configured to be integrated. And the part corresponding to the said ring part 1 and spoke 3,3,4,4 among the said metal cores 10 is coat | covered with the synthetic resin coating layer 11 which consists of urethane materials etc., for example, while the said pad The part corresponding to the part 2 is covered with the occupant side and the vehicle front side by the occupant side cover 12 and the vehicle front side cover 13, respectively, thereby constituting the pad part 2.

  Specifically, the core metal 10 is positioned inside the ring portion 1 in a ring shape inside the ring portion 1 and a core metal ring portion 10 a having an inverted U-shaped cross section, and the pad portion 2. A metal core pad portion 10b in which a shaft fitting hole 10d to be fitted is formed, and a metal core spoke portion 10c, 10c,... That connects the metal core pad portion 10b and the metal core ring portion 10a at four locations; It is constituted by. The cored bar pad portion 10b is formed in a step shape in cross-sectional view so that the outer peripheral side is bent toward the occupant side, and the center portion 2a and side portions 2b, 2b of the pad portion 2 described later at the step portion. It is connected with.

  As shown in FIG. 1, the pad portion 2 is formed in an inverted trapezoidal shape as viewed from the occupant side. The pad portion 2 includes an airbag cushion 51 and is relatively movable in the vehicle front-rear direction. The center portion 2a and side portions 2b and 2b (outer edge fixing portions) as fixing portions located on the left and right sides thereof. That is, the occupant-side cover 12 has a central portion corresponding to the central portion 2a and left and right portions corresponding to the side portions 2b and 2b made of different members, such as a polypropylene system disposed in the central portion 2a. A central cover 21 made of the above resin and an ornament 24 made of ABS resin or the like disposed on the side portions 2b and 2b.

  As shown in FIGS. 3 and 4, the central portion 2a is formed by covering the opening side of a bottomed cylindrical member having the central portion cover 21 as a bottom portion with a retainer 28 made of a metal plate member. The storage chamber 25 in which the airbag cushion 51 is stored is formed in a substantially cylindrical shape for supplying gas into the airbag cushion 51 through a through hole 28a formed in the central portion of the retainer 28. The inflator 52 is fixed in the inserted state. That is, the airbag cushion storage chamber 25 is a ring-shaped space that surrounds the inflator 52 when viewed from the passenger side, and the airbag cushion 51 is stored in a folded state in the storage chamber 25. Yes. Although described later in detail, the airbag device 5 is configured by the airbag cushion 51 and the inflator 52.

  Here, the central portion of the central cover 21 is provided with a relatively hard substantially disc-shaped emblem portion 22 that imitates an emblem of a manufacturer or the like, and the emblem portion 22 is a peripheral portion of the emblem portion 22. The center cover 21 is configured to engage with a portion other than the emblem portion 22, that is, a deployment cover portion 23 that is torn and deployed when the airbag cushion 51 is inflated and deployed as will be described later. Specifically, the deployment cover portion 23 is formed with a through-hole having a size that allows the emblem portion 22 to be disposed at the approximate center thereof, and the peripheral portion of the emblem portion 22 is the peripheral edge of the through-hole. The portion is configured to be engaged with a bent portion 23a formed to be bent in a crank shape inward of the central portion 2a. In addition, the fixing part and the unfolding part in the pad part 2 are configured so as to correspond to the emblem part 22 and the unfolding cover part 23 of the central cover 21, respectively.

  A mounting portion 22a formed in a substantially V shape in a cross-sectional view is provided on the vehicle front side of the emblem portion 22, and the mounting portion 22a is arranged so as to cover the passenger side of the inflator 52. Bolts are fastened to the bottom portion 27a of the provided bottomed cylindrical support bracket 27. The support bracket 27 has an opening edge 27b connected and fixed to the retainer 28. Between the bottom 27a and the mounting portion 22a of the support bracket 27, an inner side of a ring-shaped airbag cushion 51 described later is provided. Part of the part is clamped. As a result, the emblem portion 22 is fixed to the retainer 28 of the central portion 2a via the support bracket 27, and the inner portion of the airbag cushion 51 is also fixed to the support bracket 27, so that the airbag cushion 51 is inflated and deployed. Sometimes the emblem portion 22 is not expanded.

  Although the details will be described later with the above-described configuration, in the event of a vehicle collision, when the gas is supplied from the inflator 52 to the inside of the airbag cushion 51 and the airbag cushion 51 is inflated, the center cover 21 Only the deployment cover portion 23 is torn and deployed, and the airbag cushion 51 is inflated and deployed to the occupant side. At this time, since the emblem portion 22 of the central cover 21 is fixed to the retainer 28, the emblem portion 22 is not expanded, and the airbag cushion 51 is also fixed at the inner portion thereof. Expands and expands in a ring shape.

  Further, as shown in FIGS. 3 and 4, the central portion 2 a has a spring member 26 c with respect to the core bar pad portion 10 b disposed on the vehicle front side in the pad portion 2. 26 is elastically connected through the vehicle 26 and is configured to be relatively movable in the vehicle front-rear direction. Thus, by configuring the central portion 2a to be relatively movable, as shown in FIG. 5, when the central portion 2a is pressed forward of the vehicle (in the direction of the white arrow in the figure), the horn switch A horn (warning sound) sounds by the operation of the device 26. Hereinafter, the structure and operation of the horn switch device 26 will be described.

  As shown in FIG. 4, the horn switch device 26 includes a guide shaft 26 a, which has a lower portion screwed and fixed to the cored bar pad portion 10 b and extends toward the occupant side, and an airbag cushion storage chamber 25. A plate-like extension portion 26b that extends outward from the steering wheel W from a wall portion 25a of a bottomed cylindrical member that constitutes a part of the guide member, and the extension portion 26b and a core. It consists of a spring member 26c disposed on the outer peripheral side of the guide shaft 26a with the gold pad portion 10b, and is configured to elastically support the central portion 2a of the pad portion 2 with respect to the core metal pad portion 10b. Has been.

  The extension portion 26b is provided with a sleeve contact 26d around the periphery of the insertion hole through which the guide shaft 26a is inserted, and a pin contact 26e is provided on the core metal pad portion 10b side of the guide shaft 26a. ing. Thus, as shown in FIG. 5, when the center portion 2a of the pad portion 2 is pressed forward of the vehicle (in the direction of the white arrow in the figure), the extending portion 26b resists the elastic restoring force of the spring member 26c. However, the horn circuit (not shown) is closed when the sleeve contact 26d and the pin contact 26e come into contact with each other relative to the vehicle front side, and the horn sounds. On the other hand, when the pressing force to the central portion 2a of the pad portion 2 is lost, the central portion 2a returns to the initial position (state shown in FIG. 3) by the elastic restoring force of the spring member 26c.

  As shown in FIG. 1, the horn switch device 26 has one central position in the vertical direction at both the left and right ends of the central portion 2a of the pad portion 2, and the horizontal center at the lower end portion of the central portion 2a. Although it is preferable to provide a total of three locations at one location, this is not restrictive, and four or more locations may be provided.

  Next, the airbag cushion 51 and the inflator 52 disposed in the central portion 2a of the pad portion 2 will be described with reference to FIGS. 3 and 4. The airbag cushion 51 is formed in a bag shape. As shown in FIG. 4, the opening edge portion 51 a located on the vehicle front side is sandwiched between the retainer 28 of the pad portion 2 and the support bracket 27, while the central portion of the bottom portion 51 b is the pad portion 2. It is sandwiched between the mounting portion 22 a of the emblem portion 22 and the support bracket 27. Thus, the airbag cushion 51 is disposed so as to cover the occupant side of the inflator 52, and when the central portion of the bottom portion 51b is fixed and gas is supplied to the inside, the airbag cushion 51 is substantially donut as viewed from the occupant side. It is designed to expand into a shape.

  In the inflator 52, a gas generating agent (not shown) for generating a gas is sealed inside the case 52a, and a plurality of igniters 53 for igniting the gas generating agent are disposed. Therefore, a plurality of gas ejection ports 52b, 52b,... For discharging the gas generated by the gas generating agent are provided on the side surface of the case 52a. As described above, since the airbag cushion 51 is disposed so as to cover the inflator 52, the gas discharged from the gas ejection ports 52b, 52b,... Is reliably supplied into the airbag cushion 51. It has become so.

  On the other hand, on the side portions 2b and 2b of the pad portion 2, as shown in FIG. 1, a plurality of steering switches 29, 29,. These steering switches 29, 29,... Allow the driver to easily operate the audio (on-vehicle device) and the like. In the present embodiment, the steering switches 29 and 29 are disposed at positions farthest from the deployment cover portion 23, that is, on the outer peripheral side of the steering wheel W of the side portions 2b and 2b. What is necessary is just to make it provide in the position away from the expansion | deployment cover part 23 of the pad part 2 by the predetermined distance.

  Each steering switch 29 has a substantially U-shaped button portion 29a in a sectional view so as to open toward the inside (front of the vehicle) of the steering wheel W, as shown in section in FIG. Component) and a spring member 29b that elastically supports the button portion 29a with respect to the bracket 24a projecting inward of the side portion 2b, and a bottom surface (occupant side surface) of the button portion 29a. ) Are arranged so as to be substantially flush with the surface on the passenger side of the ornament 24. The steering switch 29 presses the button portion 29a forward of the vehicle, so that contacts (not shown) provided on the button portion 29a side and the ornament 24 side come into contact with each other, and a predetermined signal is sent to the control device. Is configured to send.

  Thus, by providing the steering switches 29 and 29 on the side portions 2b and 2b made of a relatively hard material, which are separate members from the central portion 2a of the pad portion 2, an airbag cushion is provided in the central portion 2a. Even when 51 is expanded and the center portion 2a is deformed to the outer peripheral side of the steering wheel W, the impact at the time of deformation is not directly transmitted to the switches 29 and 29, but is reduced. 29 can be effectively prevented. In addition, the steering switches 29, 29 are arranged on the outer peripheral side of the steering wheel W at the side portions 2b, 2b of the pad portion 2 at a predetermined distance from the deployment cover portion 23, so that the switches 29, 29 are connected. The transmitted impact can be further reduced, and damage to the switches 29 and 29 can be prevented more effectively. Here, the predetermined distance can be obtained even when the airbag cushion 51 disposed in the central portion 2a of the pad portion 2 is inflated to cause deformation in the central portion 2a (the initial stage of inflation of the airbag cushion 51). This means that the steering switch 29, 29 provided on the side part 2b separate from the central part 2a is damaged and the steering switch 29, 29 is not damaged and scattered to the passenger side.

  In the present embodiment, the steering switches 29, 29 are provided on the outer peripheral side of the steering wheel W of the side portions 2b, 2b located on the left and right sides of the central portion 2a of the pad portion 2, that is, both the left and right end portions of the pad portion 2. However, the present invention is not limited to this, and it may be provided only at either one of the left and right ends of the pad 2 or may be provided at the lower end of the pad 2. Here, the reason why the steering switches 29 and 29 are not provided at the upper end portion of the pad portion 2 is that the space above the emblem portion 22 is narrow and the distance between the steering switches 29 and 29 and the airbag cushion 51 is narrow. This is because the impact when the airbag cushion 51 is inflated is easily transmitted to the switches 29 and 29, and the switches 29 and 29 are easily damaged.

-Unfolded structure of the pad-
Next, the deployment structure of the pad portion 2 when the airbag cushion 51 is inflated and deployed will be described below. The pad portion 2 has a substantially V-shaped cross section as shown in FIG. 4 on the back side of the deployment cover portion 23 so that when the airbag cushion 51 is inflated, the deployment cover portion 23 is easily broken and deployed. .. Are formed.

  As shown in FIGS. 1 and 6, the breaking grooves 21a, 21a,... Are formed so as to extend radially from the peripheral edge of the through hole of the central portion 2a where the emblem portion 22 is located, respectively. Yes. Further, the left and right end portions of the center portion 2a of the pad portion 2 are also provided with fracture grooves 21a on the inner peripheral side (see FIG. 4) of the steering wheel W with respect to the wall portion 25a of the center portion 2a so as to follow the end portions. , 21a are provided, and the breaking grooves 21a, 21a are connected to the breaking groove 21a formed on the back side of the deployment cover portion 23 so as to extend in the left-right direction at a predetermined position below the emblem portion 22. Yes. This predetermined position does not impair the deployability when the airbag cushion 51 is inflated and deployed, and when the deployment cover portion 23 is deployed, a lower deployment cover portion 23c described later of the deployment cover portion 23 is a pad portion. 2 The size is set so as not to block the lower space 43 below.

  Here, among the breaking grooves 21a, 21a,..., Portions close to the steering switches 29, 29,... Provided on the side portions 2b, 2b of the pad portion 2, that is, along the left and right ends of the pad portion 2. The break grooves 21a and 21a provided are formed in shapes that facilitate breakage (for example, the groove depth is large and the groove width is large). Thus, by making the break grooves 21a, 21a close to the steering switches 29, 29 easy to break, when the airbag cushion 51 is inflated in the center portion 2a of the pad portion 2, the deformation of the center portion 2a The generated impact can be absorbed by the fracture of the fracture grooves 21a and 21a, and a large impact can be prevented from being transmitted to the switches 29 and 29.

  Further, when the airbag cushion 51 is inflated and deployed, the deployment cover portion 23 surrounded by the fracture grooves 21a, 21a,... Is opened upward as shown by a two-dot chain line in FIG. And it is divided into an upper deployment cover portion 23b and a lower deployment cover portion 23c that develop downward. The upper deployment cover portion 23b and the lower deployment cover portion 23c do not block the upper space 41 above the pad portion 2 and the lower space 43 below the pad portion 2, and improve the deployability of the airbag cushion 51, respectively. It is formed in a size that does not deteriorate. Further, the upper deployment cover portion 23b is divided into two in the vehicle width direction by a breaking groove 21a extending upward from the periphery of the emblem portion 22.

  The upper deployment cover portions 23b and 23b and the lower deployment cover portion 23c are respectively provided with hinge portions 23d, 23d and 23e at the upper end and the lower end of the undeployed state, and these hinge portions 23d and 23d. , 23e and so on, respectively, is developed in the vertical direction.

  Specifically, the upper end portion of each upper deployment cover portion 23b is connected to the retainer 28 of the pad portion 2 by a pin member 23f, and the upper deployment cover portion 23b is moved upward when the airbag cushion 51 is inflated and deployed. Even if it is unfolded, its upper end portion is prevented from being detached from the pad portion 2. That is, since the pin member 23f functions as a hinge portion 23d that rotates the upper deployment cover portion 23b upward about its upper end, the upper deployment cover portion 23b can be largely deployed upward, The developability of the bag cushion 51 can be improved.

  Further, the hinge portion 23e formed at the lower end portion of the lower deployment cover portion 23c includes a lower end portion of the lower deployment cover portion 23c and a wall portion 25a that constitutes the airbag cushion storage chamber 25 of the pad portion 2. It is comprised by the connection member 23g which connects. The connecting member 23g has a substantially hat-shaped cross section, and both end sides thereof are attached and fixed to the lower development cover portion 23c and the wall portion 25a, respectively, and the lower development cover portion 23c is attached to the wall portion 25a. When it rotates, it is configured to elastically deform at the arc portion.

  In addition, the hinge part 23d formed in the upper end part of the said upper expansion | deployment cover part 23b may be comprised not only by the pin member 23f like this embodiment but by the said connection member 23g. In this case, the connecting member is disposed so as to connect the upper end portion of the upper deployment cover portion 23 b and the retainer 28 or the vehicle front side cover 13.

  Further, the hinge portions 23d and 23e are not limited to the above-described configuration, and the center cover 21 has a double cover structure, and the break groove 21a is provided on the back side of the cover located on the passenger side, while the break groove Corresponding to the portion where 21a is formed, the cover located on the front side of the vehicle may be provided with a protrusion that protrudes forward of the vehicle in a substantially U-shaped cross section. By doing so, even if the occupant-side cover is broken by the breaking groove 21a, the vehicle front-side cover is connected to the pad portion 2, so that the deployment cover portion 23 can be deployed without being scattered.

− Deployment of airbag cushion −
Next, in the steering wheel W having the above-described configuration, a deployment operation of the airbag cushion 51 at the time of a vehicle collision will be described.

  First, when the vehicle collides, the impact is detected by a sensor (not shown) provided at the front of the vehicle, and the airbag device 5 of the steering wheel W is operated by the control device. Specifically, the igniter 53 of the airbag device 5 is ignited in accordance with a signal from the control device, and the gas generating agent in the inflator 52 is heated by the ignition to generate gas. The gas is supplied into the airbag cushion 51 through a gas ejection port 52b formed on the side surface of the inflator 52.

  When gas is supplied into the airbag cushion 51 and inflated, the deployment cover portion 23 of the pad portion 2 is pushed up to the occupant side and is broken by a breaking groove 21 a formed on the back side of the deployment cover portion 23. At the same time, the engagement with the emblem portion 22 is disengaged and deployed. That is, as shown in FIG. 6, the unfolding cover portion 23 is divided into an upper unfolding cover portion 23b, 23b and a lower unfolding cover portion 23c, and unfolds in the vertical direction around the hinge portions 23d, 23d, 23e. To do. In the unfolded cover part 23, the breaking grooves 21a, 21a on the left and right end sides of the pad part 2 formed weakly are weak in strength because the breaking grooves 21a, 21a,. Breakage occurs from the part.

  And since the emblem part 22 located in the approximate center of the pad part 2 is being fixed to this pad part 2, it does not expand | deploy, but only the said expansion | deployment cover part 23 of the circumference | surroundings expand | deploys. The cushion 51 expands and expands in a substantially donut shape when viewed from the passenger side.

  At this time, the upper deployment cover portions 23b and 23b and the lower deployment cover portion 23c are largely deployed so as not to deteriorate the deployability of the airbag cushion 51, and the upper space 41 above the pad portion 2 and below the pad portion 2 are expanded. Each lower space 43 is expanded so as not to be blocked.

  As described above, when the upper and lower deployment cover portions 23b and 23c are deployed, the relatively hard emblem portion 22 positioned substantially at the center of the center portion 2a of the pad portion 2 is fixed to the pad portion 2 without being deployed. Therefore, the emblem portion 22 can be reliably prevented from expanding and colliding with the occupant, and the impact received by the occupant can be reduced. The upper and lower deployment cover portions 23b and 23c are deployed in the vertical direction, and do not block the upper space 41 above the pad portion 2 and the lower space 43 below the pad portion, and the left and right sides of the pad portion 2 Since the airbag cushion 51 is not deployed in the direction, it is possible to secure a place for the deformation of the airbag cushion 51 when the occupant collides with the inflated airbag cushion 51.

  And according to this embodiment, steering switch 29,29 provided in the pad part 2 for a passenger | crew's operativity improvement differs from the center part 2a of the pad part 2 which deform | transforms when the airbag cushion 51 expands. Since the side portion 2b is disposed at a position away from the central portion 2a by a predetermined distance, the impact received by the switch 29, 29 when the airbag cushion 51 is inflated can be reduced. Can be prevented from being damaged and scattered to the passenger side.

  Moreover, by forming the break grooves 21a, 21a near the left and right ends of the pad portion 2, that is, near the steering switches 29, 29, more fragile than the other break grooves 21a, 21a,. Since the shock transmitted to the side portions 2b, 2b when the bag cushion 51 is inflated can be absorbed by the breakage at the break grooves 21a, 21a, the shock transmitted to the switches 29, 29 can be reduced. Breakage of the switches 29 and 29 and scattering to the occupant side can be reliably prevented.

-Modification 1 of Embodiment 1-
The steering switch 29 is not limited to the structure in which the button portion 29a having a substantially U-shaped cross section is elastically supported by the spring member 29b with respect to the side portion 2b as in the first embodiment described above. In this way, the button portion 61 having a substantially hat-shaped cross section is elastically supported by the spring members 62, 62 with respect to the side portion 2b, and only the protrusion portion 61a of the button portion 61 protrudes toward the occupant side from the ornament 24. There may be.

  Specifically, the flange portion 61b of the button portion 61 having a substantially hat-shaped cross section is formed on the bracket 24b integrally formed inside the side portion 2b by spring members 62 and 62 disposed on the vehicle front side. A through hole 24c through which the protrusion 61a of the button portion 61 can be inserted is formed in the ornament 24 that is elastically supported and constitutes a passenger-side cover of the side portion 2b. That is, the button portion 61 is elastically supported on the front side of the vehicle by the spring members 62 and 62 with respect to the side portion 2b, while the occupant side has the flange portion 61b abutting against the back side of the ornament 24. As described above, it is regulated not to move to the passenger side.

  Note that leg portions 61c and 61c extending forward of the vehicle are formed on the vehicle front side of the button portion 61, and the button portions are formed by inserting the leg portions 61c through the bracket 24b of the side portion 2b. 61 serves as a guide when moving forward of the vehicle, and contacts 63, 63 are provided on the tip of the leg portion 61c and on the bracket 24b corresponding to the tip, respectively. , 63 come into contact with each other to output a predetermined signal. Since the structure of these contacts 63, 63, etc. is the same as that of the conventional switch structure, detailed description is omitted.

  With the above configuration, even when the button portion 61 is damaged when the shock when the airbag cushion 51 is inflated is transmitted to the button portion 61 through the center portion 2a and the side portion 2b of the pad portion 2, Since 61b contacts the back side of the ornament 24, scattering to the occupant side is prevented.

  Here, a vertical rib 61d as shown in FIG. 8B may be provided on the back side (vehicle front side) of the protrusion 61a of the button portion 61. By doing so, the rigidity of the protrusion 61a can be increased, and the button portion 61 can be prevented from being damaged by an impact when the airbag cushion 51 is inflated. The vertical rib is not limited to the case where the button portion 61 has a substantially hat-shaped cross section as described above, but may be provided on a button portion having a substantially U-shaped cross section as shown in FIG. Instead of providing, the rigidity of the button part may be increased by increasing the thickness of the button part.

-Modification 2 of Embodiment 1
Further, as shown in FIG. 9, the steering switch 29 elastically supports a substantially T-shaped button portion 65 in a sectional view with respect to the side portion 2b by a spring member 66, and the occupant side of the button portion 65 is A film-like seal portion 67 (seat member) may be provided so as to cover and be substantially flush with the passenger-side surface of the ornament 24.

  Specifically, a button portion 65 having a substantially T-shaped cross section is disposed in the side portion 2b, that is, on the vehicle front side of the ornament 24, and the button portion 65 is integrally formed with the side portion 2b. A spring member 66 is disposed in front of the button portion 65 so as to be elastically supported. The ornament 24 has a hole corresponding to the button 65, and closes the hole and is substantially flush with the surface of the ornament 24 on the passenger side, for example. A seal portion 67 made of a soft resin material or a rubber member is provided. A protrusion 67a is formed on the surface of the seal portion 7 on the occupant side so as to correspond to the button portion 65, and the occupant can grasp the position of the steering switch 29 with a tactile sensation by the protrusion 67a. It is like that.

  A leg portion 65a extending forward of the vehicle is formed on the vehicle front side of the button portion 65, and the leg portion 65a passes through the bracket 24d so that the button portion 65 moves when the button portion 65 moves. In addition, contacts 68 and 68 are provided on the tip of the leg portion 65a and the bracket 24d corresponding to the tip of the leg portion 65a, respectively, and when the button portion 65 moves forward of the vehicle, The contacts 68 are in contact with each other and output a predetermined signal. Since the structure of these contacts 68, 68, etc. is the same as that of the conventional switch structure, detailed description is omitted.

With the above configuration, even when the button portion 65 or the like is damaged due to an impact when the airbag cushion 51 is inflated, the occupant side is covered with the seal portion 67, so that the button portion 65 or the like is scattered to the occupant side. Can be reliably prevented.
(Embodiment 2)
FIG. 10 shows a schematic configuration of a steering wheel W ′ provided with an airbag device according to Embodiment 2 of the present invention. The embodiment 1 is a fracture provided on the deployment cover portion 81 of the pad portion 2. Since the positions of the grooves 81a, 81a,... And the deployment method of the deployment cover portion 81 at the time of inflating and deploying the airbag cushion are different, the same portions will be denoted by the same reference numerals and only the different portions will be described. That is, in the second embodiment, the deployment cover portion 81 is deployed not only in the vertical direction but also in the lateral direction so as to cover the passenger side of the steering switch 29.

  Specifically, as shown in FIG. 10, the development cover portion 81 of the pad portion 2 is broken on the back side so as to radially extend from the periphery of the emblem portion 22 upward, right and left, and diagonally left and right. Grooves 81a, 81a,... Are formed, and by these broken grooves 81a, 81a,..., The deployment cover portion 81 is formed into an upper deployment cover portion 81b, side deployment cover portions 81c, 81c, and lower deployment cover portion 81d. It is designed to be divided.

  When the airbag cushion 51 is inflated and deployed, the upper deployment cover portions 81b and 81b are formed upward with hinge portions 81e and 81e formed at the upper ends thereof, and the lower deployment cover portion 81d is formed at the lower ends thereof. The side deployment cover portions 81c and 81c are developed downward with the hinge portion 81g as a center, while the side deployment cover portions 81c and 81c are directed toward the outer peripheral side of the steering wheel W with the hinge portions 81f and 81f formed at the left and right ends, respectively. Configured to deploy. The hinge portions 81e, 81f, 81g have the same configuration as that of the first embodiment, and thus detailed description thereof is omitted.

  This covers the occupant side of the steering switches 29, 29,... Disposed on the side portion 2b of the pad portion 2 by the side deployment cover portions 81c, 81c, so that when the airbag cushion 51 is inflated, the steering switch 29, Even when an impact is applied to 29,..., The passenger can be reliably prevented from being scattered.

  In the present embodiment, the deployment cover portion 81 is divided into five parts, that is, the upper deployment cover portions 81b and 81b, the lateral deployment cover portions 81c and 81c, and the lower deployment cover portion 81d. You may divide | segment into two right and left, and you may comprise so that it may each expand | deploy only in the left-right direction. Also in this case, since the occupant side of the steering switches 29, 29 is covered by the deployment cover portion 81, the switches 29, 29 can be prevented from being damaged and scattered to the occupant side.

(Other embodiments)
The configuration of the present invention is not limited to the above-described embodiments, but includes various other configurations. That is, in each of the above embodiments, the steering switches 29, 29,... Are provided on the side portions 2b, 2b of the pad portion 2. However, the present invention is not limited to this, and the pad portions 2 may protrude from the outer periphery. . Specifically, as shown in FIG. 11, steering switches 29, 29,... Are provided so as to protrude from the left and right end portions of the pad portion 2 into the left and right spaces 42, and the ring portion of the steering wheel W is gripped. A driver may be able to operate the switches 29, 29,... More easily.

  Further, in each of the embodiments, the emblem portion 22 and the deployment cover portion 23 (deployment cover portion 81 in the second embodiment) of the pad portion 2 are formed separately, and the peripheral portion of the emblem portion 22 and the deployment cover portion 23 are formed separately. The bent portion 23a provided at the periphery of the through-hole is engaged and integrated, and when the airbag cushion 51 is inflated and deployed, the engagement is released and the deployment cover portion 23 is deployed. However, the present invention is not limited to this, and the emblem portion 22 and the deployment cover portion 23 may be integrally formed, and a fracture groove may be provided between them.

  Furthermore, in each said embodiment, although the four spokes 3, 3, 4, and 4 are provided in the steering wheel W, it is not restricted to this, You may make three spokes.

  As described above, the steering wheel equipped with the airbag device according to the present invention prevents the operation portion disposed on the outer peripheral side of the pad portion from being damaged and scattered to the occupant side when the airbag cushion is inflated. Therefore, for example, it is particularly useful for a vehicle equipped with an airbag cushion that is deployed in a donut shape from the steering wheel toward the occupant side in the event of a vehicle collision.

It is a front view which shows schematic structure of the steering wheel which concerns on Embodiment 1 of this invention. It is a figure which shows the state which the airbag cushion provided in the steering wheel developed. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1 showing the internal structure of the steering wheel. It is the elements on larger scale of FIG. 3 which shows the internal structure of a pad part. FIG. 4 is a view corresponding to FIG. 3 showing a state where the pad portion is pressed. FIG. 2 is a view corresponding to FIG. 1 showing a state where a deployment cover portion is deployed. FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. It is the (a) front view which shows the structure of the steering switch provided with the cross-sectional hat-shaped switch cover, (b) It is VIII-VIII sectional drawing of (a). It is (a) front view which shows the structure of a steering switch provided with the seal part, (b) It is IX-IX sectional drawing of (a). FIG. 6 is a front view illustrating a schematic configuration of a steering wheel according to a second embodiment. It is a front view which shows schematic structure at the time of providing a steering switch in a pad part outer periphery.

Explanation of symbols

W, W 'Steering wheel 1 Ring part 2 Pad part 3, 4 Spoke 5 Airbag device 12 Crew side cover (cover)
21a Breaking groove 22 Emblem portion 23 Deployment cover portion 23b Upper deployment cover portion 23c Lower deployment cover portion 23d, 23e Hinge portion 51 Airbag cushion 61 Button portion 61a Protruding portion 61b Gutter portion 61d Vertical rib 65 Button portion 67 Seal portion (sheet) Element)
81 Deployment cover portion 81a Breaking groove 81b Upper deployment cover portion 81c Side deployment cover portion 81d Lower deployment cover portions 81e, 81f, 81g Hinge portion

Claims (8)

A ring portion on the outer peripheral side to be gripped by an occupant of the vehicle, a pad portion disposed substantially at the center of the ring portion, and a spoke portion connecting the pad portion and the ring portion, and a ring shape in the pad portion A steering wheel provided with an airbag device for inflating and deploying the airbag cushion stored in the vehicle to the occupant side in the event of a vehicle collision,
The pad portion is covered with a cover on the side of the occupant, and is provided around a fixed portion where the cover is not expanded even when the airbag cushion is inflated and deployed, and when the airbag cushion is inflated and deployed. A deployment part that is developed by breaking the cover along the breaking groove;
The pad portion on the outer peripheral side of the deployment portion is provided with at least an operation portion for operating the in-vehicle device, and the operation portion includes at least the components of the operation portion at the initial stage of inflation and deployment of the airbag cushion. A steering wheel provided with an airbag device, characterized by having a scattering suppression structure that suppresses scattering to an occupant side. In claim 1,
On the outer peripheral side of the pad portion, an outer edge fixing portion that is adjacent to the deploying portion and is not separated from the deploying portion and is not deployed even when the airbag cushion is inflated and deployed is provided.
A steering wheel having an airbag device, wherein the operating portion is disposed at a position spaced apart from the deployment portion in the outer edge fixing portion. In claim 1,
A steering wheel provided with an airbag device, wherein the operating portion includes a push button switch, and the passenger side of the operating portion is covered with a seat member so that the button portion of the push button switch is not exposed to the passenger side . In claim 1,
The operation unit has a pushbutton switch,
The button portion of the push button switch is formed in a substantially hat shape in cross section, and the collar portion is configured to be in contact with the cover of the pad portion so that movement to the occupant side is restricted. Steering wheel equipped with an airbag device. In any one of Claim 1 or 4,
The operation unit has a pushbutton switch,
A steering wheel having an airbag device, wherein the button portion of the push button switch includes a reinforcing rib. A ring portion on the outer peripheral side to be gripped by an occupant of the vehicle, a pad portion disposed substantially at the center of the ring portion, and a spoke portion connecting the pad portion and the ring portion, and a ring shape in the pad portion A steering wheel provided with an airbag device for inflating and deploying the airbag cushion stored in the vehicle to the occupant side in the event of a vehicle collision,
The pad portion is covered with a cover on the side of the occupant, and is provided around a fixed portion where the cover is not expanded even when the airbag cushion is inflated and deployed, and when the airbag cushion is inflated and deployed. A deployment part that is developed by breaking the cover along the breaking groove;
The pad part on the outer peripheral side of the development part is provided with at least an operation part for operating the in-vehicle device,
The airbag device is configured so that, when the airbag cushion is inflated and deployed, the deployment portion is configured to deploy around the hinge portion provided on the operation portion side and cover the operation portion. Steering wheel with In any one of Claims 1-6,
A steering wheel provided with an airbag device, wherein the deployment portion is configured such that the cover starts to break from a breaking groove in the vicinity of the operation portion when the airbag cushion is inflated and deployed. In any one of Claims 1-7,
A steering wheel provided with an airbag device, wherein the operation portion is provided at least at one of a left end portion, a right end portion and a lower end portion of the pad portion.

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