JP4760682B2 - Knee airbag device with column - Google Patents

Description

  The present invention relates to a column-attached knee airbag device that restrains a passenger's knee by inflating and deploying a knee airbag from a column cover of a steering column at the time of a collision.

Conventionally, various knee-attached airbag devices have been proposed for the purpose of protecting the occupant's knee. For example, Patent Document 1 below discloses a so-called column-attached knee airbag device in which an airbag module is disposed in a column cover of a steering column.
JP-A-9-104317

  However, in the case of the above prior art, when the steering column is an electric column, it is conceivable that when the steering column contracts at the time of collision, the fixing portion of the steering column and the airbag module interfere with each other. Therefore, in this respect, the prior art has room for improvement.

  In view of the above-described facts, an object of the present invention is to obtain a column-attached knee airbag device that can suppress or prevent the contraction operation of a column tube during a collision as much as possible.

  The knee airbag device with a column according to the invention of claim 1 is stored in a folded state in a column cover that covers the rear end side of the steering column and receives a supply of gas from a gas generating means that operates at the time of collision. An airbag module configured to include a knee airbag that inflates and deploys to the knee side, and the airbag module is slidably supported to the lower side intersecting the column tube of the steering column, and the deployment force of the knee airbag The interference avoiding means for avoiding interference between the fixing portion of the steering column on the vehicle body side and the airbag module when the column tube is contracted by sliding the airbag module away from the column tube using It is characterized by having.

  According to a second aspect of the present invention, in the column-attached knee airbag device according to the first aspect, the column cover includes a column upper cover that covers a rear end side upper part of the column tube, and a column lower cover that covers a rear end side lower part of the column tube. The airbag module includes a metal module case that accommodates the gas generation means and the folded knee airbag and has an opening formed in a bottom wall portion facing the column tube. When the knee airbag is inflated and deployed to the occupant's knee side, a part of the knee airbag protrudes from the opening to the column tube side and presses the column tube. Press the case away from the column tube to remove the column lower cover from the column upper cover. The features.

  According to the first aspect of the present invention, when a collision occurs, the gas generating means is activated to generate gas. This gas flows into a knee airbag stored in a folded state in a column cover that covers the rear end side of the steering column, and inflates and deploys the knee airbag toward the occupant's knee. Thereby, a passenger | crew's knee is protected.

  By the way, when the secondary collision load of the occupant is input to the steering column, the column tube of the steering column contracts to absorb energy at the time of the secondary collision. At this time, it is conceivable that the fixing portion of the steering column to the vehicle body side relatively moves to the airbag module side and interferes with the airbag module.

  However, according to the present invention, the airbag module is supported by the interference avoiding means so as to be slidable downwardly intersecting the column tube of the steering column. The bag module is slid away from the column tube. This avoids interference between the fixing portion of the steering column on the vehicle body side and the airbag module.

  According to the second aspect of the present invention, the module case of the airbag module is made of metal, and the gas generating means and the folded knee airbag are accommodated in the module case.

  Here, in the present invention, an opening is formed in the bottom wall of the module case, and when the knee airbag is inflated and deployed to the occupant's knee side, a part of the opening is formed from the opening in the bottom wall of the module case. The module case protrudes and expands, and a reaction force is applied to the column tube to push the module case away from the column tube. As a result, the column lower cover is detached from the column upper cover, and the airbag module is prevented from interfering with the fixing portion of the steering column to the vehicle body side.

  As described above, according to the present invention, even when the module case is made of metal, the entire module case is slid in a direction away from the steering column, and interference with the fixing portion of the steering column on the vehicle body side can be avoided. .

  As described above, the knee-attached airbag device according to the first aspect of the present invention has an excellent effect that it can suppress or prevent the contraction operation of the column tube at the time of collision as much as possible. .

  The knee-attached airbag device with a column according to the second aspect of the present invention has an excellent effect that a metal module case can be used.

[First Embodiment]
Hereinafter, a first embodiment of a column-attached knee airbag device according to the present invention will be described with reference to FIGS. Note that the arrow FR in FIG. 1 indicates the front side of the vehicle, and the arrow UP indicates the upper side of the vehicle.

  FIG. 1 is a longitudinal sectional view showing an overall configuration of a column-attached knee airbag device 10 according to the present embodiment. FIG. 2 is an enlarged vertical cross-sectional view of the main part of the column-attached knee airbag device 10. In FIG. 2, the steering column 12 is drawn in a horizontal direction.

  As shown in these drawings, an opening 16 for inserting a steering column is formed on the driver's seat side of the instrument panel 14, and the steering column 12 is disposed in a state where the steering column 12 is tilted forward through the opening 16. Yes. A column cover 18 that covers the rear end side of the steering column 12 is disposed at a position facing the opening 16 of the instrument panel 14 so as to protrude toward the cabin 19. The column cover 18 has a vertically divided structure, and is composed of a column upper cover 20 and a column lower cover 22.

(Overall structure of steering column 12)
The steering column 12 of the present embodiment is an electric steering column, and in addition to an energy absorbing mechanism that absorbs energy by contracting when a secondary collision load in the column axial direction is input during a frontal collision, an occupant switch The steering column is swung in the vertical direction around the swing center axis by the operation, and the tilting mechanism for adjusting the vertical angle of the steering wheel and the switch operation of the occupant are used to move the steering wheel in the column axis direction by a predetermined stroke. A telescopic mechanism that adjusts the front-rear position of the steering wheel by sliding within the range is provided.

  When the specific structure is outlined, the steering column 12 is provided with a cylindrical column tube 26, and a steering main shaft 28 is rotatably supported on the shaft core portion of the column tube 26. The steering main shaft 28 is divided into two in the column axis direction, and the upper shaft 28A and the lower shaft (not shown) are connected by spline fitting. Therefore, the upper shaft 28A can move relative to the lower shaft within a predetermined stroke range, but the upper shaft 28A cannot rotate relative to the lower shaft. A steering wheel 34 to which a driver's steering force is applied is fixed to a rear end portion of the upper shaft 28A by a lock nut. Accordingly, when the steering wheel 34 is rotated, the upper side shaft 28A and the lower side shaft are integrally rotated around the axis, and the intermediate shaft (not shown) connected to the lower side shaft by the universal joint is connected. The steering force is transmitted to the steering gear box.

  The column tube 26 that covers the steering main shaft 28 is also divided into two in the column axial direction (double tube structure), and is disposed on the inner tube 36 disposed on the passenger side and on the opposite passenger side (steering gear box side). The outer tube 38 is connected by spline fitting. Further, the outer tube 38 is set to have a diameter larger than that of the inner tube 36, and the inner tube 36 slides into the outer tube 38 and contracts at the time of a secondary collision with the occupant's steering wheel 34. Further, the outer tube 38 is supported by a pipe-like instrument panel reinforcement (not shown) that is a high-strength and high-rigidity member that extends in the instrument panel 14 along the vehicle width direction.

  Supplementing this point, at a predetermined position in the longitudinal direction of the instrument panel reinforcement, a steering support having portions extending to both the vehicle front side and the vehicle rear side across the instrument panel reinforcement in a plan view is fixed by welding or the like. Yes. On the front end side of the steering support, a lower bracket (not shown) is fixed to the upper front end of the outer tube 38 so as to be swingable about the swing center axis. Further, a housing 40 is fixed to the rear end side of the steering support and is formed in a substantially rectangular frame shape in which the column tube 26 is disposed in a penetrating state. During the tilt operation, the column tube 26 moves up and down in the housing 40. In other words, since a part of the tilt mechanism and a part of the telescopic mechanism part of the electric tilt / telescopic drive mechanism part are integrated with the outer tube 38, the outer tube 38 is supported by the tilt / telescopic drive mechanism part. As a result, the column tube 26 is hollowly supported in the substantially rectangular frame-shaped housing 40, and the steering column 12 is allowed to move up and down by a tilt operation.

(Overall configuration of the knee-attached airbag device 10)
Next, the overall configuration of the column-attached knee airbag device 10 will be described.

  The column-attached knee airbag device 10 includes a metal module case 48 formed in a substantially box shape, and an inflator as a gas generating means formed in a substantially cylindrical shape and accommodated on the inner rear end side of the module case 48. 50, and an airbag module 54 including a knee airbag 52 stored in a folded state on the inner front end side of the module case 48, and a lower surface side serving as an opening side of the airbag module 54 is closed. And an airbag door 60.

  A plurality of hook portions 56 are formed at predetermined intervals on the front wall portion 48A and the rear wall portion 48B of the module case 48. Correspondingly, on the inner side surface (the surface facing the inner tube 36) of the column lower cover 22, the front wall portion 22A and the rear wall portion 22B are provided on the inner tube 36 side at a predetermined interval in the column axial direction. It is erected. The front wall portion 22 </ b> A and the rear wall portion 22 </ b> B are formed with a locking hole 58 in which the hook portion 56 can be locked, and the hook module 56 is locked in the locking hole 58, whereby the airbag module 54. The open side of is closed.

  Further, the airbag door 60 is formed at a portion between the front wall portion 22A and the rear wall portion 22B of the column lower cover 22, and along the tear line (breaking portion) 62 configured as a thin portion in this embodiment. When the column lower cover 22 is broken, the airbag door 60 is deployed in front, rear, left and right.

  Moreover, although the knee airbag 52 is folded by bellows folding in FIG. 1, it is not restricted to this, You may fold by roll folding and you may fold combining both. Further, supplementing the deployed shape of the knee airbag 52, the central portion 52A that expands below the position where the steering column 12 is disposed is relatively thin due to the presence of the column lower cover 22. Both side portions 52B that expand on the side of the position are relatively thick because they expand between the instrument panel 14 and the occupants' knees.

  The airbag module 54 described above is an annular main body of a combination switch 68 fixed below the rear end side of the inner tube 36 of the steering column 12 and near the lower end 40A of the housing 40 and the rear end portion of the inner tube 36 described above. The portion 68A is disposed between the lower portion 68A ′.

(Structure of the main part of the column-attached knee airbag device 10)
Next, a configuration of a main part of the column-attached knee airbag device 10 will be described.

  As shown in FIGS. 2 and 3, the module case 48 of the airbag module 54 described above is slidably supported on the inner tube 36 via a mounting bracket 70 as interference avoiding means. More specifically, the bottom wall portion 48C of the module case 48 is disposed to face the rear end side of the inner tube 36, and an opening 72 is formed on the front side thereof.

  Further, a mounting bracket 70 formed in a substantially L shape in a side view is disposed on the rear side of the bottom wall portion 48 </ b> C of the module case 48. The mounting bracket 70 includes a first bracket 78 fixed to the bottom wall 48C side of the module case 48 with a bolt 74 and a nut 76, a second bracket 80 fixed to the lower surface of the outer peripheral portion of the inner tube 36 by welding, and the like. It is constituted by.

  The first bracket 78 is formed in an approximately L shape in a side view, and a mounting seat 82 disposed in contact with the rear side of the bottom wall portion 48C of the module case 48 in a surface contact state, and a rear of the mounting seat 82. And a slide portion 84 that is raised from the end portion and formed in a U-shape with a lip in a plan view. A bolt insertion hole 86 is formed in the central portion of the mounting seat 82, and the mounting seat 82 is fixed to the bottom wall portion 48 </ b> C of the module case 48 with a bolt 74 and a nut 76 using the bolt insertion hole 86. . The slide portion 84 includes a main body portion 84A that rises at a right angle from the rear end portion of the mounting seat 82, and a pair of U-shaped guide portions 84B that are integrally formed on both side portions of the main body portion 84A. ing. A bolt insertion hole 88 is formed on the upper center side of the main body portion 84A.

  On the other hand, the second bracket 80 is formed in a substantially rectangular flat plate shape, and a concave portion 90 that matches the outer peripheral surface shape of the inner tube 36 is formed at the upper end portion thereof. The recess 90 is in contact with the lower outer peripheral surface on the rear end side of the inner tube 36 and is attached to the inner tube 36 by welding or the like. Further, the plate thickness of the second bracket 80 is set to be thicker than the plate thickness of the first bracket 78 and is set so as to substantially match the gap width of the guide portion 84B of the slide portion 84 of the first bracket 78. ing. Further, an elongated hole 92 extending in the column approaching and separating direction is formed at the center of the second bracket 80.

  Then, the second bracket 80 is inserted into the guide portion 84B of the slide portion 84 of the first bracket 78, the bolt insertion hole 88 of the first bracket 78 is positioned at the upper end portion position of the long hole 92, and the bolt 94 and the nut 96 are used. By fastening with a predetermined torque, the first bracket 78 is fixed to the second bracket 80, and as a result, the airbag module 54 is cantilevered via the mounting bracket 70 on the inner tube 36. The predetermined torque refers to a torque that presses the module case 48 away from the column tube 26 (arrow A direction in FIGS. 2 and 3) using the bag inflation pressure of the knee airbag 52. In addition, the thickness of the second bracket 80 is made thicker than the thickness of the first bracket 78 to provide a difference in thickness. This is because the support rigidity is ensured by the plate thickness of the existing member, while the plate thickness of the member existing on the column axial direction side is made thin to avoid interference with the lower portion 40A of the housing 40 as much as possible.

(Operation and effect of this embodiment)
Next, the operation and effect of this embodiment will be described.

  When a frontal collision occurs (or when a frontal collision is predicted), the state is detected by a collision detection unit (not shown) and output to the airbag ECU. When the airbag ECU determines that the airbag is activated, the driver side airbag device is activated to inflate the driver seat airbag on the steering wheel 34 and the column-attached knee airbag device 10 is also activated. Is done. That is, a predetermined current is passed through the inflator 50 of the column-attached knee airbag device 10 to activate the inflator 50. Thereby, gas is generated from the inflator 50 and supplied into the knee airbag 52 stored in the folded state, and the knee airbag 52 is inflated. When the inflation pressure of the knee airbag 52 acting on the column lower cover 22 reaches a predetermined value, the column lower cover 22 is broken along the tear line 62 set in the column lower cover 22, and the airbag door 60 is deployed. . As a result, the knee airbag 52 is inflated and deployed below and to the side of the steering column 12, and the occupant's knees are received by the left and right side portions 52B interposed between the instrument panel 14 and the occupant's knees. Protected.

  The impact at the time of a frontal collision is also absorbed by the energy absorption mechanism of the steering column 12. That is, when a frontal collision occurs, a thrust load from the steering gear box is input to the intermediate shaft, but energy is absorbed by the contraction of the intermediate shaft. Further, when the upper body of the occupant is received by the driver's seat airbag from the steering wheel 34 side, a load (arrow F in FIG. 1) is input to the steering column 12 through the steering wheel 34 in the axial direction. Is done. When the input load is equal to or greater than a predetermined value, the steering main shaft 28 and the column tube 26 contract (the upper side shaft 28A relatively moves axially into the lower side shaft, and the inner tube 36 becomes the outer tube. It moves in the axial direction relatively to the 38 side). The frictional energy generated in this process absorbs the collision energy input from the steering wheel 34 side.

  By the way, when the secondary collision load (arrow F in FIG. 1) of the occupant is input to the steering column 12 and the column tube 26 of the steering column 12 contracts, the housing is a fixed portion of the steering column 12 to the vehicle body side. It is conceivable that the lower portion 40 </ b> A of the 40 moves relatively to the airbag module 54 side and interferes with the airbag module 54.

  However, in the present embodiment, since the airbag module 54 is supported by the mounting bracket 70 so as to be slidable downward on the axis perpendicular to the column tube 26 of the steering column 12, the following effects are obtained.

  That is, assuming that the state shown in FIG. 2 is a state before the column-attached knee airbag device 10 is activated, when the inflator 50 is activated from this state and the knee airbag 52 starts to expand, as shown in FIG. The part 52C protrudes from the opening 72 of the bottom wall 48C of the module case 48 and expands, and presses the inner tube 36 from below. As a result, the reaction force R from the inner tube 36 acts on the knee airbag 52 and the module case 48. When the reaction force R exceeds the fastening torque of the bolt 94 and the nut 96 that connect the first bracket 78 and the second bracket 80, the first bracket 78 slides along the second bracket 80 and the module case 48. As a result, the entire airbag module 54 is displaced away from the inner tube 36. Since the inflator 50 is attached in the module case 48, the inflator 50 also slides together with the module case 48. At this time, since the pressing force is transmitted from the hook portion 56 of the module case 48 to the column lower cover 22, the column lower cover 22 is detached from the column upper cover 20 (the engagement state by the engagement means by the resin claw or the like is changed). And the column lower cover 22 as well as the air bag module 54 is slid (retracted) together in a direction away from the inner tube 36. As a result, interference between the lower part 40A of the housing 40, which is a fixing portion of the steering column 12 to the vehicle body side, and the airbag module 54 is avoided.

  As shown in FIG. 5, after the airbag module 54 is slid, the lower portion 40A of the housing 40 moves relative to the position where it interferes with the front wall 48A of the module case 48. At this time, a part of the knee airbag 52 is moved. 52C is also drawn inwardly from the opening 72 of the bottom wall portion 48C of the module case 48 to the inside of the module case 48. Therefore, even if the portion 52C may slightly interfere with the lower portion 40A of the housing 40, The part 52C is easily deformed and has no problem.

  Thus, according to the present embodiment, even when the module case 48 is made of metal, the entire airbag module 54 including the module case 48 slides away from the inner tube 36 of the steering column 12, Interference between the airbag module 54 and the lower portion 40A of the housing 40 that serves as a fixing portion of the steering column 12 to the vehicle body side can be avoided. As a result, it is possible to suppress or prevent the contraction operation of the column tube 26 from being inhibited at the time of a frontal collision as much as possible.

  In the present embodiment, the metal module case 48 is used. However, the present invention is not limited to this, and the module case may be constituted by a cloth or the like that is a material having both flexibility and flexibility. In this case, the bolt standing on the inflator 50 may be inserted into the bolt insertion hole 86 of the mounting seat 82 of the first bracket 78 and fixed by the nut 76. Supplementally, in the case of the metal module case 48, the interference between the module case 48 and the lower portion 40A of the housing 40 hinders the contraction operation when the column contracts, but a flexible module case such as cloth is used. In this case, even if the module case and the lower portion 40A of the housing 40 interfere with each other, the module case is deformed flexibly, so that there seems to be no problem. However, depending on the vehicle model, the distance between the lower portion 68A 'of the main body 68A of the combination switch 68 and the lower portion 40A of the housing 40 may be further narrowed, and the installation conditions of the airbag module may be severe. In such a case, if the inflator 50 can be slid downward using the mounting bracket 70, interference between the inflator 50 and the lower portion 40A of the housing 40 can be avoided. In that sense, the present invention can be made of cloth or the like. It is meaningful to apply to an airbag module using a flexible module case.

[Second Embodiment]
Hereinafter, the second embodiment will be described with reference to FIGS . 6 and 7 . Note that the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. This second embodiment is a reference example.

  As shown in FIGS. 6 and 7, in the second embodiment, unlike the first embodiment described above, a cloth module case 100 is used. In the fabric module case 100, hooks (not shown) attached to the peripheral edge portions thereof at predetermined intervals are locked in locking holes (not shown) formed in the front wall portion 22A and the rear wall portion 22B of the column lower cover 22. By doing so, it is attached to the front wall portion 22A and the rear wall portion 22B.

  On the other hand, the inflator 50 is disposed at the upper part on the rear end side of the module case 100, and the bolt 102 erected from the inflator 50 passes through the module case 100 and passes the rear end side of the inner tube 36 (adjacent position of the combination switch 68 ) Is fixed to the mounting bracket 104 by a nut 106.

Here, the front wall portion 22A of the column lower cover 22 has a positional relationship that interferes with the lower portion 40A of the housing 40 when the column contracts. Therefore, in the second embodiment, the hinge portion 108 formed of a thin groove-like groove portion is provided in the vicinity of the base portion of the front wall portion 22A of the column lower cover 22 (on the side opposite to the airbag door 60). It is formed along. Further, on the side of the front wall portion 22A where the airbag door 60 is formed, a rib 110 connecting the root portion and the front door 60A of the airbag door 60 has a predetermined length along the front wall portion 22A. A plurality are formed at intervals.

(Action / Effect)
According to the above configuration, as shown in FIG. 7, when the inflator 50 is actuated and the bag inflation pressure of the knee airbag 52 reaches a predetermined value at the time of a frontal collision, the column lower cover 22 is broken along the tear line 62. The front door 60A of the airbag door 60 is deployed to the front side in the column axial direction, and the rear door 60B of the airbag door 60 is deployed to the rear side in the column axial direction.

  Here, in this embodiment, since the groove-shaped hinge portion 108 is formed in the vicinity of the root portion of the front wall portion 22A, the rigidity of this portion is low. Therefore, when the front door 60A is deployed forward in the column axial direction, the deployment force of the front door 60A is also transmitted to the front wall portion 22A, and the front door 60A is in the same direction as the deployment direction of the front door 60A (the arrow in FIG. 7). B direction). Accordingly, interference between the lower portion 40A of the housing 40, which is a fixed portion of the steering column 12 to the vehicle body side, and the front wall portion 22A provided upright on the column lower cover 22 is avoided. As a result, also in this embodiment, as in the first embodiment described above, it is possible to suppress or prevent the contraction operation of the column tube 26 at the time of a frontal collision as much as possible.

  In the present embodiment, the thin hinge portion 108 is formed by forming a concave groove in the vicinity of the root portion of the front wall portion 22A, thereby configuring the interference avoidance means. Therefore, an installation space is provided in the vicinity of the front wall portion 22A. The front wall portion 22 </ b> A can be rotated together with the front door 60 </ b> A of the airbag door 60 without separately providing a member, a mechanism, or the like that requires. Therefore, according to the present embodiment, the front wall portion 22A can be rotated in the deployment direction of the front door 60A of the airbag door 60 without sacrificing the space around the front wall portion and at a low cost. it can.

  Furthermore, in the present embodiment, the rib 110 is provided to connect the two on the base portion of the front wall portion 22A of the column lower cover 22 and on the side where the front door 60A of the airbag door 60 is formed. , The unfolding force is directly transmitted to the front wall portion 22A via the rib 110. Accordingly, the front wall portion 22A is rotated in the same direction as the deployment direction of the front door 60A substantially simultaneously with the deployment of the front door 60A. As a result, according to the present embodiment, the responsiveness when the front wall portion 22A rotates in the deployment direction of the front door 60A can be improved, and the front wall portion 22A interferes with the lower portion 40A of the housing 40 accordingly. The probability of avoiding this can be increased. Further, the rib 110 is formed in a substantially triangular shape that connects the base portion of the front wall portion 22A and the inner side surface of the front door 60A, and can be formed simultaneously with the manufacture of the column lower cover 22. Cost reduction can be achieved.

  In the present embodiment, the rib 110 is set at the connection portion between the front wall portion 22A and the front door 60A. However, the present invention is not limited to this, and the rib 110 may be eliminated. Even in this case, since the unfolding force of the front door 60A is transmitted to the front wall portion 22A to some extent, if the front door 60A is unfolded forward in the column axial direction at an extremely high speed, the front wall portion 22A is centered on the hinge portion 108. As a result, the front door 60A is rotated to some extent in the unfolding direction.

Further, the rib 110 of this embodiment is different in function from a so-called reinforcing rib that is generally widely used as a well-known and commonly used technique, and increases the area of the connecting portion between the front door 60A and the front wall portion 22A. Thus, it is grasped as a rib that plays a role of transmitting more of the deploying force of the front door 60A to the front wall portion 22A and drawing the front wall portion 22A in the deploying direction of the front door 60A by the unfolding operation of the front door 60A. In that sense, the connecting portion, which is a superordinate concept of the rib 110, includes configurations other than the rib 110. For example, the ribs are usually formed in a thin plate shape as a single unit, and a plurality of the ribs are often installed at a predetermined interval, but the gap between adjacent ribs is filled with meat so that the plurality of ribs are mounted on the vehicle. Even if a thick wall portion such as a circular arc shape, a right triangle shape, or a rectangular shape is set in a side view at the connection portion between the base portion of the front wall portion 22A and the front door 60A, the rib 110 is connected to the width direction. Perform the same function .

[Supplementary explanation of the above embodiment]
In each of the above-described embodiments, the column-attached knee airbag device 10 is activated by a frontal collision. However, the present invention is not limited to this, and a front-crash sensor is mounted on the center of the front bumper. The column-attached knee airbag device 10 may be configured to operate at the time of collision prediction (prediction).

It is a longitudinal cross-sectional view which shows the whole structure of the knee airbag apparatus with a column which concerns on 1st Embodiment by a side view. It is a principal part expanded longitudinal sectional view which expands and shows the principal part of the column-attached knee airbag device shown in FIG. It is a disassembled perspective view centering on the attachment bracket shown by FIG. FIG. 3 is an operation explanatory view corresponding to FIG. 2 showing a state in which the airbag module is slid. FIG. 5 is an operation explanatory diagram corresponding to FIG. 4 showing a state in which the column tube is contracted from the state shown in FIG. 4. It is a principal part expansion longitudinal cross-sectional view corresponding to FIG. 2 which expands and shows the principal part of the knee airbag apparatus with a column which concerns on 2nd Embodiment. FIG. 7 is an operation explanatory view corresponding to FIG. 4 showing a state when the knee airbag is inflated and deployed from the state shown in FIG. 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Knee airbag apparatus with column 12 Steering column 18 Column cover 20 Column upper cover 22 Column lower cover 22A Front wall part 22B Rear wall part 26 Column tube 40 Housing (fixing part to the vehicle body side)
48 module case 48C bottom wall 50 inflator (gas generating means)
52 knee airbag 52C part 54 module case 60 airbag door 62 tear line 70 mounting bracket (interference avoiding means)
72 openings

Claims (2)

A knee cover that is stored in a folded state in a column cover that covers the rear end side of the steering column and that is inflated and deployed to the occupant's knee side upon receipt of gas supplied from the gas generating means that operates in the event of a collision. An airbag module;
By supporting the airbag module in a slidable downward direction intersecting the column tube of the steering column, by sliding the airbag module away from the column tube using the deployment force of the knee airbag, Interference avoiding means for avoiding interference between the fixing portion of the steering column on the vehicle body side and the airbag module when the column tube is contracted;
A knee-attached airbag device with a column. The column cover is divided into a column upper cover covering the rear end side upper part of the column tube and a column lower cover covering the rear end side lower part of the column tube,
Further, the airbag module includes a metal module case that accommodates the gas generating means and the knee airbag in a folded state and has an opening formed in a bottom wall portion facing the column tube,
When the knee airbag is inflated and deployed to the occupant's knee side, a part of the knee airbag protrudes from the opening to the column tube side and presses the column tube. Push the column lower cover away from the column upper cover by pressing away from the tube.
The knee-attached airbag device with a column according to claim 1.

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