JP2007307969A - Steering wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extend a restrainable area of an occupant by an airbag in the initial stage of expansion when the airbag provided in a bag holder of a steering wheel expands and deploys. <P>SOLUTION: A thin portion 3b is extended to a periphery edge portion 3e side from the center side of a bag cover 3 to be formed to the periphery edge portion 3e, and a lower cover 30 is constituted so as not to regulate the opening motion when the bag cover 3 opens with expansion and deployment of the airbag 22, and so as to be partially deformed when the periphery edge portion 3e of the bag cover 3 is brought into contact with the lower cover. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a steering wheel for a vehicle in which a bag cover is opened by an air bag accommodated in a bag holder, and the air bag is inflated and deployed through the opening.

An air bag device is attached to a steering wheel of a vehicle in order to protect an occupant during a vehicle collision. The airbag device includes an airbag and an inflator that supplies gas to the airbag. The airbag and the inflator are accommodated in a bag holder (see, for example, Patent Document 1). A bag cover is fixed to a side wall of the bottom wall of the bag holder so as to cover the airbag, and a portion of the bag holder on the vehicle body side is covered with a lower cover. The lower cover is provided in such a manner that a large gap is not formed between the peripheral edge portion and the peripheral edge portion of the bag cover so as not to impair the design. Further, a part of the bag cover is formed in advance as a thin groove-like thin part, and when the airbag is inflated, the thin part is cleaved to open the bag cover. The airbag is inflated by the gas supplied from the inflator when the vehicle collides, and is inflated and deployed in the vehicle compartment through the opening of the bag cover.
JP 2000-85512 A

  In order to further improve the occupant restraint performance, the airbag is quickly deployed in the area where the occupant is restrained. That is, even when the airbag is in the initial stage of inflation, the deployment area is close to the deployment area when the inflation is completed. It is desirable to extend to. In the above conventional technology, the effect is achieved by enlarging the openable region of the bag cover, but other configurations such as an airbag device and a steering wheel other than the bag cover are only improved by the configuration of the bag cover. It is inevitable that the deployment area of the airbag in the area blocked by the object is limited.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an area in which an occupant can be restrained by an airbag at the initial stage of inflation when the airbag provided in the bag holder of the steering wheel is inflated and deployed. The object is to provide a steering wheel that can be widened.

  In order to solve the above-described problems, the invention according to claim 1 is a bag holder that accommodates an airbag that is filled with gas from an inflator and inflates, and a bag cover that covers a portion of the airbag located on the passenger side. A lower cover that covers a portion of the bag holder located on the vehicle body side and has a peripheral portion provided at a position in contact with the peripheral portion of the bag cover, and the airbag is formed on the bag cover at the time of a vehicle collision. In the steering wheel having an airbag device that opens the bag cover while opening the thin-walled portion and is inflated and deployed in the vehicle interior through the opening, the thin-walled portion extends from the center side of the bag cover to the peripheral side. The lower cover is formed to the same peripheral edge, and the bag cover is accompanied by the inflation and deployment of the airbag. And gist partially deformable be configured when the peripheral portion of the bag cover so as not to restrict the opening operation is in contact during the opening Te.

  According to this structure, the part which can open a bag cover also becomes large by forming a thin part to the peripheral part of a bag cover. However, when the bag cover configured as described above is to be opened by inflation of the airbag, the peripheral edge portion thereof may come into contact with the peripheral edge portion of the lower cover. Even when such contact occurs, the lower cover is partially deformed by this contact force. Therefore, it is possible to prevent the opening operation of the bag cover from being restricted by the lower cover and to open the bag cover greatly. Accordingly, since a large deployment area in the initial stage of inflation of the airbag is ensured, the area in which the occupant can be restrained by the airbag in the early stage of inflation can be widened.

  In order to solve the above-mentioned problem, the invention described in claim 2 surrounds an airbag that is inflated by being filled with gas from an inflator by a bottom wall thereof and a side wall standing on a peripheral edge of the bottom wall. A bag holder for accommodating the bag, a bag cover fixed to the side wall of the bag holder so as to cover a portion located on the passenger side of the airbag, and a portion located on the vehicle body side of the bag holder A lower cover provided at a position where a peripheral portion can come into contact with the peripheral portion of the bag cover, and the airbag opens the bag cover while cleaving a thin portion formed on the bag cover at the time of a vehicle collision. In the steering wheel having an airbag device that is inflated and deployed in the vehicle interior through the opening, the side wall of the bag holder is the bag The fixed portion of the bag cover is configured to be relatively displaceable with respect to the adjacent portion in accordance with the opening operation of the bar, and the lower cover is configured so that the bag cover is inflated and deployed with the airbag. The gist of the invention is that the bag cover is partially deformable when the peripheral edge of the bag cover comes into contact with the bag cover so that the opening operation is not restricted when the bag is opened.

  According to this structure, the thin part formed in the bag cover is cleaved by the force generated by the inflation of the airbag, and the bag cover is opened. Along with the opening operation of the bag cover, the fixed portion of the side wall to which the bag cover is fixed is displaced relative to the other portions, so that the bag cover is also displaced with the displacement of the fixed portion. Therefore, the bag cover has a larger openingable portion. The bag cover configured in this way has a large amount of displacement at the time of opening operation, so that the peripheral portion thereof may come into contact with the peripheral portion of the lower cover, but even if such contact occurs. The lower cover is partially deformed by this contact force. Therefore, it is possible to prevent the opening operation of the bag cover from being restricted by the lower cover and to open the bag cover greatly. Accordingly, since a large deployment area in the initial stage of inflation of the airbag is ensured, the area in which the occupant can be restrained by the airbag in the early stage of inflation can be widened.

  In addition, as a specific configuration of the steering wheel that relatively displaces a part of the side wall of the bag holder in accordance with the opening operation of the bag cover, the configuration according to claim 3 or 4 can be adopted. It is.

  According to a third aspect of the present invention, in the steering wheel according to the second aspect, at least a part of a side wall of the bag holder is divided in advance between a portion to which the bag cover is fixed and a portion adjacent thereto. The gist of this is

  In this configuration, the portion of the bag holder where the bag cover is fixed is divided with respect to the adjacent portion, so that the force applied to this portion becomes difficult to disperse due to the opening operation of the bag cover. Acts on this part. Therefore, the side wall is relatively displaced with respect to the other part at the part where the fixed part to which the bag cover is fixed is divided as described above.

  According to a fourth aspect of the present invention, in the steering wheel according to the second aspect, the side wall of the bag holder is at least partially between a portion to which the bag cover is fixed and a portion adjacent thereto. The gist is that a portion to be broken is formed that is broken by the force generated by the opening operation.

  According to the configuration, the force applied to the side wall portion to which the bag cover is fixed by the opening operation of the bag cover is distributed over the entire side wall until the planned fracture portion is broken, but after the planned fracture portion is broken The force applied to this part is not easily distributed to other adjacent parts, and as a result, the force concentrates on this part. Therefore, the side wall is relatively displaced relative to the other adjacent parts at the part where the fixed part to which the bag cover is fixed is broken as described above.

  According to a fifth aspect of the present invention, in the steering wheel according to any one of the first to fourth aspects, the lower cover has a portion that contacts when the bag cover is opened. The gist is that the pair of fragile portions extending along the extending direction of the thin-walled portion from the peripheral portion so as to be sandwiched are broken so as to be relatively displaceable with respect to a portion adjacent thereto.

  According to this configuration, the weak portion of the lower cover is broken by the force acting by the contact when the bag cover is opened, and the portion of the lower cover that contacts the bag cover is partially deformed with respect to the adjacent portion. Therefore, even if the lower cover comes into contact with the bag cover, the opening operation of the bag cover can be prevented from being restricted by the lower cover, and a large opening portion of the bag cover can be secured.

  A sixth aspect of the present invention is the steering wheel according to the fifth aspect, wherein the lower cover includes a reinforcing portion that extends from an end portion of the fragile portion along an extending direction of the fragile portion. To do.

  According to this configuration, when the bag cover comes into contact with the lower cover, the portion sandwiched by the pair of weakened portions of the lower cover can be bent and deformed starting from the tip of the reinforcing portion, and the airbag can be in an initial stage of inflation. The development area can be secured more suitably.

The invention according to claim 7 is the steering wheel according to claim 5,
The lower cover is characterized in that the portion sandwiched between the pair of weakened portions is set to have higher rigidity than the other portions.

  According to this configuration, in the lower cover, the portion sandwiched between the pair of fragile portions, that is, the portion that can be relatively displaced is set to have high rigidity, so that the portion is locally displaced. For this reason, a weak part can be broken more reliably and this part can be relatively displaced now more suitably.

  In the steering wheel of the present invention, the opening operation of the bag cover is not restricted by the lower cover when the airbag provided in the bag holder is inflated and deployed. Therefore, since the bag cover is opened wide and a deployable region in the initial stage of inflation of the airbag is secured, the range in which the occupant can be restrained by the airbag is widened even in the early stage of inflation.

(First embodiment)
A first embodiment embodying the present invention will be described below with reference to FIGS. FIG. 1 is a front view of a steering wheel W in the present embodiment, and FIG. 2 is a cross-sectional view showing a cross-sectional structure of the steering wheel W along the line AA in FIG. In the state where the steering wheel W is attached to the vehicle, the right side portion in FIG. 2 is located above and the left side portion is located below.

  As shown in FIG. 1, the steering wheel W includes a ring portion 2, a bag cover 3 disposed in the center of the ring portion 2, and three spoke portions 4 that extend radially from the ring portion 2 to the bag cover 3. And. Further, a thin portion 3b is formed on the back surface of the design portion 3a on which the design of the bag cover 3 is formed, and the design portion 3a partitioned by the thin portion 3b is formed by the tearing of the thin portion 3b. The bag 22 is opened when the bag 22 is inflated.

  As shown in FIG. 2, the ring portion 2 is constituted by a ring cored bar 5 made of, for example, a steel pipe and a covering body 7 a covering the same, and the spoke part 4 is made of a spoked cored bar 6 a made of, for example, die-cast aluminum. (6b, 6c) and a covering body 7b covering them. The coverings 7a and 7b and the bag cover 3 are made of a soft synthetic resin material such as foamed polyurethane. A bag holder 10 is provided below the bag cover 3 (vehicle body side). The bag holder 10 includes a bottom wall 11 having a mounting hole 11 a formed at the center, and a side wall 12 erected from the peripheral edge of the bottom wall 11.

  As shown in FIG. 2, an airbag device 20 including an inflator 21 and an airbag 22 is accommodated in the bag holder 10. The airbag 22 is inflated and deployed by filling the gas from the inflator 21 at the time of a vehicle collision. The airbag 22 inflated and deployed avoids contact between the steering wheel W and the occupant, for example, and protects the occupant. The inflator 21 has a cylindrical shape having substantially the same diameter as the attachment hole 11a formed in the bag holder 10, and a flange 21a is formed on the outer periphery thereof. Then, the inflator 21 is inserted into the mounting hole 11a, and the bolt 14b penetrating the flange 21a and the airbag 22 is screwed into each of the bolt holes 11b formed around the mounting hole 11a. Thus, the inflator 21 and the airbag 22 are fixed to the bag holder 10. Moreover, in the state accommodated in the bag holder 10 in this way, the airbag 22 is folded in a bellows shape, and the periphery thereof is surrounded by the side wall 12.

  As shown in FIG. 2, the bag cover 3 is fixed to the bag holder 10. More specifically, the bag cover 3 is fixed by a rivet 14c that passes through the fixing portion 3c and a bolt hole 12a formed in the side wall 12 of the bag holder 10. A hinge portion 3 d extends from the fixed portion 3 c of the bag cover 3 toward the ring portion 2, and the tip of the hinge portion 3 d is connected to the design portion 3 a of the bag cover 3.

  The steering wheel W is provided with a lower cover 30 so as to cover the vehicle body side of the bag holder 10. The lower cover 30 is made of a soft synthetic resin material such as foamed polyurethane, for example, and covers the bag holder 10 with a bottom portion 30a and side portions 30b. The lower cover 30 is provided at a position where the peripheral edge 30 c of the side portion 30 b can come into contact with the peripheral edge 3 e of the bag cover 3.

  Next, the formation aspect of the thin part 3b formed in the bag cover 3 of this embodiment is demonstrated with reference to FIG. FIG. 3 is an arrow view showing the bag cover 3 viewed from the direction indicated by the arrow B in FIG.

  As shown in FIG. 3, the thin portion 3b extends from the central portion of the bag cover 3 toward the peripheral portion 3e and extends to the peripheral portion 3e. When the thin portion 3b is broken by the expansion of the airbag 22, the portion sandwiched between the pair of thin portions 3b formed in this way is separated from the adjacent portion and is rotatable about the hinge portion 3d as a fulcrum. Will be supported. Therefore, the portion of the bag cover 3 that is sandwiched between the pair of thin portions 3b is displaced with the hinge portion 3d connected to this portion as a fulcrum when the airbag 22 is inflated.

Next, a specific structure of the above-described bag holder 10 will be described with reference to FIG. FIG. 4 is a perspective view of the bag holder 10.
As shown in FIG. 4, the bag holder 10 includes a substantially hexagonal bottom wall 11 having a mounting hole 11 a formed at the center, and a side wall 12 erected from the peripheral edge of the bottom wall 11. . A plurality (four in this embodiment) of bolt holes 11b are formed around the mounting hole 11a of the bottom wall 11 at substantially equal intervals along the circumferential direction of the mounting hole 11a. A plurality of (three in this embodiment) mounting seats 13 are formed in the bottom wall 11 at substantially equal intervals in the circumferential direction of the mounting hole 11a. Bosses 13b having bolt holes 13a project from the upper surfaces of the mounting seats 13, respectively. In addition, the position where this attachment seat part 13 is formed respond | corresponds to the position of the three spoke parts 4 (refer FIG. 1) of the steering wheel W, respectively.

Next, the structure of the lower cover 30 will be described with reference to FIG. FIG. 5 is a perspective view showing a structure on the inner peripheral surface of the lower cover 30.
As shown in FIG. 5, a pair of concave stripes, that is, a fragile portion 31 extends from the peripheral portion 30c on the inner peripheral surface of the lower cover 30, that is, the surface facing the bag holder 10 (see FIG. 1). Is formed. As shown in FIG. 3, the fragile portion 31 extends along a direction in which the thin portion 3b extends from a position corresponding to each thin portion 3b. And the position where a pair of weak part 31 is formed is set to the position where the part pinched by it contacts the peripheral part of the bag cover 3 displaced by opening operation of the bag cover 3. The rigidity of the fragile portion 31 is set so as to be broken by the contact force generated by this contact, and the portion sandwiched between the fragile portions 31 of the lower cover 30 is partially broken with respect to the adjacent portion when the fragile portion 31 is broken. It can be deformed. As shown in FIG. 5, the lower cover 30 is formed with a rib 32 as a reinforcing portion extending from the terminal portion 31 a of each fragile portion 31 along the extending direction. The rib 32 enhances the rigidity of the portion located on the vehicle body side (lower side in FIG. 5) from the portion sandwiched between the pair of fragile portions 31 of the lower cover 30.

  Next, the operation | movement aspect of the airbag apparatus 20 of 1st Embodiment is demonstrated based on FIG. 6 and FIG. 6 and FIGS. 7A and 7B are sectional views showing a state in which the airbag 22 is inflated and the bag cover 3 is opened.

  When an impact of a predetermined value or more is applied to the vehicle, such as when a vehicle collision occurs, this is detected by a collision detection sensor (not shown), and this detection signal is input to a control circuit (not shown). The control circuit activates the inflator 21 in response to the input of the detection signal. That is, the gas generating agent is ignited by an ignition device (not shown) of the inflator. As a result, the gas in the inflator 21 is supplied to the airbag 22 and the airbag 22 starts to expand. As shown in FIG. 2, since the portion of the airbag 22 located on the passenger side is covered with the bag cover 3, the bag cover 3 receives a pressing force from the inflating airbag 22. And thereby, the thin part 3b is gradually cleaved toward the peripheral part 3e side from the center of the design part 3a. As FIG. 6 shows, until the thin part 3b is cleaved until it reaches the hinge part 3d, it gradually opens with the progress of the cleaving. In this state, the airbag 22 is deployed through the opening formed in the bag cover 3, but the size of the opening of the bag cover 3 is not sufficient, and the deployable region is also limited. It has become.

  Then, as shown in FIG. 7A, when the tearing of the thin portion 3b reaches the peripheral portion 3e, the bag cover 3 rotates about the hinge portion 3d, and the peripheral portion 3e is also displaced. It will be. Here, since the peripheral edge 30c of the lower cover 30 is provided at a position where the peripheral edge 3c can come into contact with the peripheral edge 3e of the bag cover 3, the peripheral edge 3e is displaced to come into contact with the lower cover 30. The fragile portion 31 formed as shown in FIG. 5 is gradually broken. And since the rib 32 is formed in the lower cover 30 and the deformation | transformation of the formation part is restrained, this contact force acts on the part pinched by the pair of weak parts 31 of the lower cover 30 and acts. As a result, as shown in FIG. 7A, this portion is bent and deformed inward from the tip 32a of the rib 32 as a starting point. Depending on the manner of assembly of the lower cover 30 and the manner of opening operation of the bag cover 3, the lower cover 30 may be deformed outward as shown in FIG.

  As the lower cover 30 is partially deformed in this way, the opening operation of the bag cover 3 is suppressed from being restricted by the lower cover 30, and the bag cover 3 is greatly opened. Therefore, since the airbag 22 can be deployed through such a wide open opening, the airbag 22 is deployed in a wide area in the initial stage of inflation.

The effects of the steering wheel W of the present embodiment described above will be described below.
(1) Since the thin wall portion 3b extends from the center side of the bag cover 3 to the peripheral edge portion 3e and is formed up to the peripheral edge portion 3e, a large openable portion of the bag cover 3 can be secured. Furthermore, a pair of weak parts 31 are formed in the lower cover 30, and the part sandwiched between the weak parts 31 is partially deformed when the peripheral part 3e of the bag cover 3 comes into contact. For this reason, it is possible to prevent the opening operation of the bag cover 3 from being restricted by the lower cover 30 and to open the bag cover 3 greatly. Accordingly, a large deployment area of the airbag 22 in the initial stage of inflation is ensured, and an area in which the occupant can be restrained by the airbag 22 in the initial stage of inflation is widened.

  (2) The lower cover 30 is provided with a rib 32 extending from the terminal end portion 31 a of the fragile portion 31 along the extending direction of the fragile portion 31. With this configuration, when the bag cover 3 comes into contact with the lower cover 30, the portion sandwiched between the pair of fragile portions 31 of the lower cover 30 is locally bent and deformed starting from the tip 32 a of the rib 32. Thus, the deployment region of the airbag 22 in the initial stage of inflation can be secured more suitably.

(Second Embodiment)
Next, a second embodiment that embodies the present invention will be described with reference to FIGS. 8 and 9 with a focus on differences from the first embodiment. FIG. 8 is a perspective view of the bag holder 10, and FIG. 9 is a cross-sectional view showing a state in which the airbag 22 is inflated and the bag cover 3 is opened. Note that members having the same functions as those in the first embodiment are given the same reference numerals, and descriptions thereof are omitted.

  In 2nd Embodiment, the structure which expands the openable area | region of the bag cover 3 is employ | adopted by displacing the side wall 12 of the bag holder 10 to which the bag cover 3 is fixed. Moreover, the thin part 3b is extended and formed in the bag cover 3 to the peripheral part 3e similarly to 1st Embodiment. The specific configuration will be described below.

  As shown in FIG. 8, slits 16 are formed between a portion of the side wall 12 positioned between the mounting seat portions 13 and a portion where the mounting seat portion 13 is formed. The slit 16 has a shape that extends obliquely so that the portion positioned on the proximal end side of the side wall 12 is positioned on the bolt hole 12a side, that is, on the side of the side wall 12 where the bag cover 3 is fixed. have. Further, as shown in FIG. 9, the boundary 15 between the bottom wall 11 and the side wall 12 of the bag holder 10 is formed with a concave streak and its rigidity is reduced.

Next, the operation | movement aspect of the airbag apparatus 20 of 2nd Embodiment is demonstrated based on FIG.
As described above, when the airbag 22 is inflated, a force is applied to the bag cover 3 to rotate the hinge 3d as a fulcrum. And this force is propagated also to the side wall 12 to which each bag cover 3 is fixed. The side wall 12 has a portion where the bag cover 3 is fixed and another portion adjacent to the side wall 12 separated by a slit 16, so that the portion where the bag cover 3 is fixed is rotated by the rotation of the bag cover 3. The generated force acts in a concentrated manner. Therefore, the portion of the side wall 12 rotates toward the outside of the bag holder 10 with the boundary portion 15 as a fulcrum. For this reason, only the part to which the bag cover 3 is fixed in the side wall 12 is relatively displaced with respect to other adjacent parts.

  At this time, the bag cover 3 is further displaced along with the rotation of the side wall 12, and the peripheral edge 3e is also displaced. Here, since the peripheral edge 30c of the lower cover 30 is provided at a position where the peripheral edge 3c can come into contact with the peripheral edge 3e of the bag cover 3, the peripheral edge 3e is displaced to come into contact with the lower cover 30. The fragile portion 31 formed as shown in FIG. 5 is gradually broken. And since the rib 32 is formed in the lower cover 30 and the deformation | transformation of the formation part is restrained, this contact force acts on the part pinched by the pair of weak parts 31 of the lower cover 30 and acts. As a result, as shown in FIG. 9, this portion is bent and deformed inward starting from the tip 32 a of the rib 32. As the lower cover 30 is partially deformed in this way, the opening operation of the bag cover 3 is suppressed from being restricted by the lower cover 30, and the bag cover 3 is greatly opened. Therefore, since the airbag 22 can be deployed through such a wide open opening, the airbag 22 is deployed in a wide area in the initial stage of inflation.

The steering wheel W of the present embodiment described above can exhibit the following operational effects in addition to the effects equivalent to (2) described above.
(3) The side wall 12 of the bag holder 10 is configured so that a portion where the bag cover 3 is fixed can be displaced relative to a portion adjacent to the side of the bag cover 3 when the bag cover 3 is opened. The thin portion 3b formed in the bag cover 3 is cleaved by the force generated by the inflation of the airbag 22, and the bag cover 3 is opened. With this configuration, the fixing portion of the bag cover 3 on the side wall 12 is displaced relative to the adjacent portion in accordance with the opening operation of the bag cover 3, so that the bag is moved along with the displacement of the fixing portion. The cover 3 is also displaced. Therefore, the bag cover 3 also has a large openingable portion. Furthermore, in the present embodiment, since the pair of fragile portions 31 are formed in the lower cover 30 so that the lower cover 30 is partially deformed, the opening operation of the bag cover 3 is not greatly restricted. It becomes open. Accordingly, since the airbag 22 is deployed while passing through the enlarged space in the initial stage of inflation, the deployment area in the early stage of inflation becomes wide, and the area in which the occupant can be restrained by the airbag 22 in the early stage of inflation becomes wide. .

  (4) The slit 16 separates the portion of the side wall 12 where the bag cover 3 is fixed and the portion adjacent thereto. Therefore, the force that acts on the fixing portion of the side wall 12 on the bag cover 3 by the opening operation of the bag cover 3 is difficult to disperse to adjacent portions, and as a result, this force is concentrated and acts on this fixing portion. Therefore, the slit 16 can be largely displaced relative to the portion of the side wall 12 where the fixed portion of the bag cover 3 is adjacent.

In addition, 1st and 2nd embodiment can also be implemented with the following forms which changed these suitably.
-As a method of reinforcing the portion of the lower cover 30 that is located on the bottom 30a side from the end portion 31a of the fragile portion 31, a method of improving rigidity by increasing the thickness of the portion other than the rib 32, for example, can also be adopted. It is.

  -Although the weak part 31 is extended and formed in the middle from the peripheral part 30c of the lower cover 30, the position where the weak part 31 is formed is not limited to this, For example, the weak part 31 extends more to the bottom part 30a side. It may be done. That is, if the weak part 31 is formed so that the part which the bag cover 3 contacts in the lower cover 30 can deform | transform, the formation aspect can be changed suitably.

  -The part which the bag cover 3 of the lower cover 30 contacts may be formed of a soft material having extensibility so that the part partially extends and deforms when the bag cover 3 comes into contact.

  Further, as shown in FIG. 10, by forming the rib 320 over the entire side portion 30b of the lower cover 30, the rigidity of the side portion 30b is made higher than that of other portions, and the side portion 30b of the lower cover 30 is increased. As a whole, the base end portion may be displaced as a fulcrum. As a method of setting the rigidity of this portion high, in addition to providing the rib 320, for example, a method of increasing the rigidity by increasing the plate thickness of the portion can be employed.

  -In 2nd Embodiment, although the side wall 12 showed the structure by which the part to which the bag cover 3 is fixed, and the part adjacent to this were previously divided | segmented by the slit 16, it replaces with this and the following structures are shown. Is also possible. That is, a portion to be broken is formed between the portion of the side wall 12 where the bag cover 3 is to be fixed and the portion adjacent thereto to reduce the plate thickness and reduce the rigidity. The force applied to the portion of the side wall 12 to which the bag cover 3 is fixed by the opening operation of the bag cover 3 is distributed to the adjacent portion until the planned fracture portion is broken, but after the planned fracture portion is broken, The force applied to the part becomes difficult to be dispersed, and as a result, the force concentrates on this part and acts. Therefore, the fixed portion of the side wall 12 to which the bag cover 3 is fixed is relatively displaced with respect to the other portions adjacent to the bordered portion. In addition, as the side wall 12, the portion to which the bag cover 3 is fixed is formed of a soft material having extensibility, so that this portion expands and deforms with the opening operation of the bag cover 3 and is adjacent to the adjacent portion. You may employ | adopt the structure which carries out relative displacement.

  -In 2nd Embodiment, although the bag cover 3 showed the structure by which the thin part 3b was extended | stretched to the peripheral part 3e, the bag cover 3 is a peripheral part with rotation of the fixing part of the bag cover 3 in the side wall 12. If it is cleaved up to 3e, it is not always necessary to form the thin part 3b up to the peripheral part 3e.

  In the present embodiment, the configuration in which all the side wall 12 portions to which the bag cover 3 is fixed is rotated is shown, but a configuration may be adopted in which at least a part of these portions can rotate.

The front view of the steering wheel in 1st Embodiment. Similarly, sectional drawing which shows the cross-section of the steering wheel along the AA line of FIG. Similarly, the arrow view which shows the bag holder seen from the direction shown by arrow B in FIG. Similarly, the perspective view of a bag holder. Similarly, the perspective view which shows the structure in the internal peripheral surface of a lower cover. Similarly, sectional drawing which shows the state which the airbag expanded and the bag cover was opened. (A), (b) is sectional drawing which shows the state which the airbag expanded and the bag cover was similarly opened. The perspective view of the bag holder in 2nd Embodiment. Similarly, sectional drawing which shows the state in which the bag expanded and the bag cover was opened. Sectional drawing which shows the modification about the deformation | transformation aspect of a lower cover.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 3 ... Bag cover, 3b ... Thin part, 3e ... Peripheral part, 10 ... Bag holder, 11 ... Bottom wall, cover, 12 ... Side wall, 30 ... Lower cover, 30c ... Peripheral part, 31 ... Fragile part, 31a ... Terminal part, 32 ... rib, 32a ... tip, W ... steering wheel.

Claims (7)

A bag holder that accommodates an airbag that is filled with gas from an inflator to inflate, a bag cover that covers a portion of the airbag located on the passenger side, and a portion that covers a portion of the bag holder that is located on the vehicle body side and a peripheral portion thereof A lower cover provided at a position in contact with a peripheral edge of the bag cover, and the airbag opens the bag cover while cleaving a thin portion formed in the bag cover at the time of a vehicle collision, and through the opening In a steering wheel having an airbag device inflated and deployed in a vehicle interior,
The thin wall portion extends from the center side of the bag cover to the peripheral edge side and is formed to the peripheral edge portion,
The lower cover is configured to be partially deformable when the peripheral portion of the bag cover comes into contact with the bag cover so that the opening operation is not restricted when the bag cover is opened as the airbag is inflated and deployed. A steering wheel characterized by that. A bag holder for housing an airbag that is inflated by being filled with gas from an inflator so as to be surrounded by a bottom wall thereof and a side wall standing on a peripheral edge of the bottom wall; and located on the passenger side of the airbag A bag cover that is fixed to the side wall of the bag holder so as to cover the portion, a portion that covers the portion of the bag holder that is located on the vehicle body side, and a peripheral portion thereof is provided at a position that can contact the peripheral portion of the bag cover. A steering wheel having an airbag device that opens the bag cover while cleaving a thin portion formed in the bag cover in the event of a vehicle collision and is inflated and deployed in the vehicle compartment through the opening. In the wheel
The side wall of the bag holder is configured so that the fixed portion of the bag cover can be displaced relative to the adjacent portion in accordance with the opening operation of the bag cover,
The lower cover is configured to be partially deformable when the peripheral portion of the bag cover comes into contact with the bag cover so that the opening operation is not restricted when the bag cover is opened as the airbag is inflated and deployed. A steering wheel characterized by that. The steering wheel according to claim 2,
The steering wheel according to claim 1, wherein at least a part of a side wall of the bag holder is divided in advance between a portion to which the bag cover is fixed and a portion adjacent thereto. The steering wheel according to claim 2,
The side wall of the bag holder is formed with a planned fracture portion that is broken by a force generated by the opening operation of the bag cover at least partly between a portion where the bag cover is fixed and a portion adjacent thereto. Steering wheel characterized by In the steering wheel according to any one of claims 1 to 4,
The lower cover is formed by breaking a pair of fragile portions extending along the extending direction of the thin portion from the peripheral portion so that the portion that contacts when the bag cover is opened sandwiches the portion from both sides. A steering wheel configured to be relatively displaceable with respect to a portion adjacent thereto. The steering wheel according to claim 5,
The lower cover includes a reinforcing portion that extends from an end portion of the fragile portion along an extending direction of the fragile portion. The steering wheel according to claim 5,
The lower cover is configured such that a portion sandwiched between the pair of fragile portions is set to have higher rigidity than the other portions.

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