Air bag apparatus and instrument panel structure for supporting air bag apparatus

An air bag apparatus includes a folded air bag, an inflator arranged to discharge a high pressure gas into the air bag at a collision of the vehicle, and a container member receiving the air bag, covering a non-deployment side of the air bag, and retaining the inflator. The container member includes a rigid base plate supporting the inflator and the air bag, covering one part of the non-deployment side of the air bag, and supporting a reaction force of the air bag at a deployment of the air bag, and a flexible panel including a connecting portion connected with the base plate, covering the other part of the non-deployment side of the air bag, and being arranged to restrict inflation of the air bag on the non-deployment side at the deployment of the air bag.

BACKGROUND OF THE INVENTION

The present invention relates to an air bag apparatus arranged to protect an occupant at a collision of a vehicle, and an instrumental panel for supporting the air bag apparatus.

The air bag apparatus for absorbing the impact at the collision of the vehicle is installed inside the instrument panel of the vehicle compartment.

In the recent year, the social and technical request to reduce the weight of the overall vehicle is increased. That is, from a viewpoint of social requirement, the reduction in the emission gas of the vehicle is recognized as an important problem for the preservation of earth environment. It is considered that it is the most rational solution to improve fuel economy by the weight reduction of the vehicle. Therefore, it is requested to reduce the weight of whole components of the vehicle, and also the air bag apparatus.

From the viewpoint of the technical request, the air bag apparatuses are mounted to various parts of the vehicle because of the spread of a side air bag, a curtain air bag, and so on. Through the weight of one air bag apparatus does not have great effect, the weight of all the air bag apparatuses mounted on the vehicle can not be disregarded because many air bag apparatuses are mounted on the vehicle. Even if the air bag apparatuses for lessening or losing the occupant's injury may increase in number in the future, it is not thought that the number of the air bag apparatus decreases, therefore the needs for the art for the weight reduction are by no means small.

Moreover, from the viewpoint of the technical request, it is important to downsize the air bag apparatus. The progress of IT (Information technology) applies in the vehicle, and there is a request to bring an operation function and a control function together in the instrument panel. However, even in the conventional vehicles, the instrument panel has devices for vehicle control (for example, ECU), an air conditioner, and control devices for the air conditioner, and audio systems. Moreover, the air bag apparatus is disposed in the instrument panel, and it is in a difficult situation on a layout. In order to add IT devices and so on to such instrument panel, there are needs to miniaturize already-existing built-in apparatus more highly because there is a limit also in the size of an instrument panel naturally from the function.

For this reason, the development for attaining a weight saving, without spoiling the function of the air bag apparatus is progressing, and the air bag device aiming at a weight saving is also proposed, for example with patent documents 1, 2 and 3.

A patent document 1 (Japanese Patent Application Publication No. 2001-97162) shows an air bag apparatus including a folded air bag, a case having an upper chamber opened in an upper surface, and a lower chamber connected with a lower portion of the upper chamber, and an inflator received in the lower chamber.

The case is made of a sheet of metal plate by stamping with deep drawing. The folded air bag is received in the upper chamber.

The case includes a pair of flange portions each formed by bending from a periphery of the upper surface of the upper chamber. These flange portions are fixed to an instrument panel by fastening members to fix an upper part of the case. A bottom portion of the lower chamber is a vehicle body by fastening members to fix a lower part of the case. The case is made of a sheet of the metal sheet, and accordingly it is possible to reduce manufacturing cost and weight of the air bag apparatus.

A patent document 2 (Japanese Patent Application Publication No. 1993 (H05)-193432) shows an air bag apparatus including an air bag, a inflator of cylinder type or bomb type, and a case having a reinforcement frame member made of metal, and a cover member made of resin material, and located inside the reinforcement frame member. The cover member has a substantially U-shaped cross section. The air bag is received in the case.

A fitting hole is formed in a first end surface of the reinforcement frame member. One end of the inflator is inserted from the fitting hole to the reinforcement frame member, and engaged with a keyhole formed in a second end surface of the reinforcement frame member. Consequently, the inflator is fixed to the reinforcement frame member. The inflator serves as a reinforcement member for the reinforcement frame member.

In the apparatus described in the patent document 2, part of the case is skeleton structure, and it is possible to downsize the air bag apparatus without spoiling the intensity of the case.

A patent document 3 (Japanese Patent Application Publication No. 2003-165409) shows an air bag apparatus including a cylinder type or bomb type inflator, a pair of brackets, fixing members, and a separation cloth. Each end of the inflator is fixed to one bracket. Each fixing member connects between upper portions of the brackets. Each end of the separation cloth is retained, by claws, to one fixing member.

The separation cloth is suspended, in the form of U-shape, between the fixing members to cover a lower opening portion between the brackets. The folded air bag is received above the inflator.

The air bag apparatus described in the patent document 3 does not use the conventional metal case, and it is possible to achieve the light weight of the air bag apparatus.

SUMMARY OF THE INVENTION

However, in the air bag apparatus described in the patent document 1, the case includes the upper chamber and the lower chamber, and an overall height of the air bag apparatus becomes high. Accordingly, it is not possible to be employed in a vehicle which is unable to sufficiently ensure a sufficient installation space inside the instrument panel.

In the air bag apparatus patent described in the patent document 2, part of the case is the skeleton structure, and it is possible to reduce the weight. Moreover, the cylinder type inflator is received in the substantially U-shaped bottom portion of the cover member, and it is possible to slightly lower the overall height of the air bag apparatus relative to the air bag apparatus of the patent document 1.

However, there is a limit to lowering the height of the cover member because the cover member receives the air bag.

Moreover, the cylinder type inflator is received in the bottom portion of the cover member, and the height of the cover member may become high in accordance with the type of the inflator. Accordingly, it is not possible to produce a thin air bag apparatus.

On the other hand, the air bag apparatus described in the patent document 3 does not need the case. Accordingly, it is possible to reduce the weight readily, and to lower the overall height of the air bag apparatus.

However, the inflator penetrates at a substantially center portion of each bracket, and there is need for extra increasing the height of the brackets by the diameter of the inflator.

Moreover, the folded air bag is received between the brackets, and is rolled downward of the inflator from the both sides of the inflator. Accordingly, the separation cloth covering the lower opening portion between the brackets receives the reaction force at the inflation of the air bag, and inflates downwards. Therefore, there is need for a space into which the separation cloth inflates, and it is not possible to lower the overall height of the air bag apparatus.

The separation cloth is disposed between the brackets, and portions for fixing the air bag apparatus to the vehicle body are limited to lower portions of the brackets. When the air bag apparatus is mounted to a portion which does not have the vehicle body below the air bag apparatus, there is need for special mounting members to install the air bag apparatus. Accordingly, a number of components for the air bag apparatus is increased, and it is not possible to facilitate the assembly operation.

It is an object of the present invention to provide an air bag apparatus aimed to solve the above mentioned problem, and devised to reduce size, weight, and thickness.

According to one aspect of the present invention, an air bag apparatus comprises a folded air bag, an inflator arranged to discharge a high pressure gas into the air bag at a collision of the vehicle, and a container member receiving the air bag, covering a non-deployment side of the air bag, and retaining the inflator, the container member including a rigid base plate supporting the inflator and the air bag, covering one part of the non-deployment side of the air bag, and supporting a reaction force of the air bag at a deployment of the air bag, and a flexible panel including a connecting portion connected with the base plate, covering the other part of the non-deployment side of the air bag, and being arranged to restrict inflation of the air bag on the non-deployment side at the deployment of the air bag.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a partial cutaway perspective view showing an air bag module according to a first embodiment of the present invention.FIG. 2shows an exploded perspective view showing the air bag module ofFIG. 1.FIG. 3shows a cross sectional view showing the air bag module.FIG. 4shows a sectional view taken along a section line IV-IV ofFIG. 3.FIG. 5shows a schematic perspective view showing the instrument panel when the air bag module is attached to an air bag receiving portion of an instrument panel.

FIGS. 1˜5show an air bag apparatus for a passenger seat. An air bag module1is received in an instrument panel2provided forward of the passenger seat (not shown).

Air bag module1includes a saucer-shaped retainer3of sheet metal formed by press forming.

Retainer3is in the form of a rectangle. Retainer3is formed with a pair of circular inflator fitting holes3aarranged at an interval in a longitudinal direction. A plurality of mounting bolts5for mounting inflator4are provided around inflator fitting holes3ato protrude downwards.

A folded air bag6is mounted on an upper side of retainer3. A wrapping cloth7covers around air bag6and retainer3to keep the folded shape of air bag6. Wrapping cloth7is made of nylon base cloth, and is in the form of a band. Wrapping cloth7is formed with a break line7aextending along the longitudinal direction of air bag module1. Break line7ais in the form of a perforation to break at the inflation of air bag6.

Air bag6is made of non-coated nylon cloth having, for example, substantially 315 denier and 200 g/m2weight. The non-coated nylon cloth is cut into the shape of mushroom. Air bag6is formed into the shape of a bag by sewing the periphery of the mushroom-shaped nylon base cloth. Gas supply holes or gas inlet holes6aare formed in the base cloth located on the lower side at the time of the inflation, to align with inflator fitting holes3aformed in retainer3.

Flexible panel is provided below retainer3to cover the lower side of air bag module1. Flexible panel is, for example, a flexible backup member8including a first backup member (first flexible sheet) and a second backup member (second flexible sheet).

Backup member8is made of non-coated nylon base cloth which has, for example, substantially 315 denier and 200 g/m2weights. Backup member8is formed in the shape of a rectangle having a width sufficiently larger than a width of retainer3. First and second backup members of backup member8are superimposed on each other except for one end portion of each backup member. Circular fitting holes8aare formed in the superimposed portion of backup member8to align with inflator fitting holes3aformed in retainer3. A plurality of bolt holes8bare formed around fitting holes8a. Each of mounting bolts5is inserted into one of bolt holes8b.

Each of first and second backup members of backup member8includes a flap portion8cformed on one end side of each flexible sheet of backup member8. Each flap portion8cis formed with cylindrical mounting portions8dserving as a panel connection portion.

One end portion of each flap portion8cis turned back, and is sewn in a superposed state. Consequently, each mounting portion8dis formed in the shape of the cylinder. Adjacent two of mounting portions8ddefines a recessed portion or notch portion8e, Recessed portions8eare arranged at intervals in the longitudinal direction, as shown inFIG. 2. One end portion of each mounting portion8dis protruded from a long hole or oblong hole12bof a frame portion12aprovided on a lower surface or back surface of a cover panel12to protrude downward as described later.

A rigid base plate9is provided below backup member8. Base plate9covers non-deployment side area of air bag6to support a reaction force of the deployment of air bag6with a body construction (body member) described later.

Base plate9is made of a substantially rectangular metal sheet which has a length longer than a length of retainer3. Base plate9is formed with inflator fitting holes9aeach aligned with one of inflator fitting holes3aof retainer3. Inflator fitting holes9aof base plate9have the size substantially identical to the size of inflator fitting holes3a. A plurality of bolt holes9bare formed around inflator fitting holes9a. Mounting bolts5are inserted into bolt holes9b.

Base plate9has a width substantially identical to a diameter (width) of flange4aof inflator4. Accordingly, it is possible to ensure strength to sufficiently support the reaction force at the inflation of air bag6, to possibly decrease the width by removing redundant portions, and to reduce the weight. Base plate9includes mounting end portions9cupwardly folded, in the form of a crank, on the both sides of base plate9in the longitudinal direction.

Each mounting end portion9cis formed with mounting holes9d. A fastening member or fastener10such as bolt is inserted into each of mounting holes9dto fix base plate9on mounting seat portions12eprotruding from the back surface of cover panel12. Base plate9is formed with bolt holes9eon a center portion thereof, and on both end portions thereof. A fastening member or fastener11is inserted into each of bolt holes9eto fix base plate9on mounting seat portions2bof instrument panel2.

Inflator4is formed in the shape of a disc, as shown inFIG. 2. Inflator4includes a plurality of gas discharge holes4blocated on an outer surface of an upper portion thereof, and flange4aprotruding outwards at a center portion. Flange4aof inflator4is formed with a plurality of bolt holes4ceach receiving one of mounting bolts5provided in retainer3.

Thus, retainer3, backup member8, and base plate9serve as a container member for holding inflator4.

A harnesses16shown inFIG. 2connects inflator4and a collision sensing section (not shown). Two of inflators4are usually used, and are identical or similar in shape to each other. Accordingly, one of inflators is shown, and the other of inflators is omitted.

On the other hand, instrument panel2forward of the passenger seat is formed with a recessed air bag module receiving portion2aserving as an air bag apparatus mounting portion, as shown inFIG. 5. Mounting seat portions2bare provided in air bag module receiving portion2ato protrude inward. Each mounting seat portion2bis formed with a bolt hole2cinto which one of fastening members11is inserted through one bolt hole9eof base plate9. Mounting seat portions2bare provided through impact absorbing structure (not shown) such as collapsible brackets. Mounting seat portions2bare arranged in intervals in a widthwise direction of the vehicle. These portions serves as a body member for mounting air bag apparatus1.

Cover panel12covers upper opening portion2dof air bag module receiving portion2a. Cover panel12is formed by molding a resin having the same color as instrument panel2. Accordingly, cover panel12covers a region on a deployment side of air bag6, and forms doors by tearing along tear line12fat the time of the deployment of air bag6.

Cover panel12is fit in opening portion2dof air bag module receiving portion2awithout clearance, as shown inFIG. 4. Cover panel12includes a frame portion12aprotruding from the back surface thereof. Reinforcement members18are fixed, for example, by heat caulking, at connection portions between the back surface of cover panel12and frame portion12a.

Frame portion12ahas a substantially square frame shape slightly larger than the folded shape of air bag6so as to receive folded air bag6by insertion from below. Air bag module1is attached to the back surface of cover panel12so that a lower end portion of frame portion12aabuts on both bent portions of base plate9, as shown inFIG. 3.

Mounting seat portions12eare provided to protrude outward from the outer surface of frame portion12a. Mounting end portions9cabut on mounting seat portions12efrom below. Each fastening member10is inserted through one of bolt holes9dof mounting portions9c, and screwed into a screw hole13aof a nut member13provided on an upper side of mounting seat portion9e. Consequently, both ends of base plate9are fixed to the back surface of cover panel12.

Rectangular long holes12bare formed in a front side surface and a rear side surface of frame portion12a. Long holes12bare arranged at intervals substantially identical to the intervals between adjacent two of mounting portions8dof backup member8. Cylindrical mounting portions8dare protruded outwards from long holes12b, and then retaining rod14is inserted into these protruded cylindrical mounting portions8d, so that mounting portions8dof backup member8are fixed to frame portion12a. These mounting portions8dserves as connection portion of backup member8to base plate9.

Retaining rods14are made of elongated or long metal sheet, as shown inFIG. 2. Periphery of each retaining rod14is folded into L-shape by press or stamping, and formed with a flange portion14ato increase strength. Each retaining rod14is formed with rivet holes14bon the center portion thereof, and on both end portions thereof.

Rivets15are inserted into rivet holes14b, and retaining rods14are retained to frame portion12aby these rivets15. Between adjacent two of rivet holes14bto reduce the weight, there is provided a thinning hole14cwhich is in the form of a slit, to reduce the weight.

Tear lines12fis formed in the back surface of cover panel12, and tears at the time of the inflation of air bag6. Tear lines12fincludes longitudinal tear lines12gand a lateral tear line12h. Longitudinal tear lines12gand lateral tear line12hare in the form of H-shape. Base plate9is mounted to cover panel12so that intersections12iof longitudinal tear lines12gand lateral tear line12hbecome near mounting position of the base plate.

Hereinafter, the operation of the above-described air bag apparatus is illustrated.

At the assembling operation of air bag module1, first, folded air bag6is mounted on retainer3. In this state, wrapping cloth7covers air bag6and retainer3to hold the folded shape of air bag6.

Next, fitting holes8aof first and second backup members of backup cloth8are aligned with each other in the superposed state, and bolt holes8baround fitting holes8aare fit over mounting bolts5, from below retainer3. Then, an upper portion of inflator4having gas discharge holes4bis fit, from below, in one inflator fitting hole9aof base plate9. Each bolt hole9bof base plate9and the corresponding bolt hole4cof inflator4are fit over one mounting bolt5provided to protrude downward from retainer3. In this state, each nut5ais inserted into one end of one mounting bolt5, and tightened. The upper portion of inflator4protrudes into air bag6, as shown inFIGS. 3 and 4, and the periphery of each gas discharge hole6is airtightly sandwiched between retainer3and base plate9. Accordingly, it is possible to prevent gas leakage from gas discharge holes6awhen gas discharge holes4bof inflators4discharge high pressure gas into air bag6.

Next, air bag module1is attached to the back surface of cover panel12. At the mounting of air bag module1, each cylindrical mounting portion8dof one end portion of backup member8is inserted through one of long holes12bof frame portion12a, and to protrude outside frame portion12a.

In this state, one end of each retaining rod14is inserted into cylindrical mounting portions8d, as shown inFIG. 1. Each rivet15is inserted through one rivet hole14binto a rivet hole (not shown) of frame portion12a, and riveted or staked. Each retaining rod14is retained to the outer surface of frame portion12a.

Consequently, backup member8covers the bottom portion of air bag6spreading on both sides of base plate9, as shown inFIG. 4.

Next, each fastening member10is inserted, from below, through one bolt hole9dof mounting end portions9cprovided on both ends of base plate9. Then, this fastening member10is inserted into one screw hole13aof one nut member13, tightened, and air bag module1is assembled. In this state, folded air bag6is received inside frame portion12a. The height of base plate9becomes substantially identical to the height of lower end of frame portion12a. Moreover, only the bottomed portion or lower portion of disc type (disc-shaped) inflator4protrudes below base plate9, and it is possible to reduce the thickness of air bag module1. Moreover, there is no need for the case for receiving air bag6and inflator4, and it is possible to reduce the size and the weight of air bag module1.

After air bag module1is assembled as mentioned above, air bag module1is received in air bag module receiving portion2aformed in instrument panel2, as shown inFIG. 5. Each fastening member11is inserted through one bolt hole9eof base plate9into one bolt hole2cof mounting seat portions2b. Each fastening member11is tightened, from below mounting seat portion2b, by a nut (not shown) inserted from an opening located at a position oblique below instrument panel2before a glove box is attached. Consequently, base plate9of air bag module1received in air bag module receiving portion2ais fixed to instrument panel2. Cover panel12covers upper opening portion2bof air bag module receiving portion2awithout clearance. Accordingly, air bag module1can not be seen from the outside.

Backup member8covers the bottom portion of air bag module1protruding on both sides of narrow width base plate9, and can be transformed readily. Accordingly, air bag module1can be readily received in air bag module receiving portion2aeven when area of opening portion2dof air bag module receiving portion2ais substantially identical to or slightly smaller than area of folded air bag6. It is possible to reduce time for mounting of air bag module1, and to facilitate the assembly operation.

In a case in which the instrument panel is assembled, in advance, in sublines (supplier park) adjacent to a final assembly line of the vehicle, by installing internal equipments, it is possible to mount the air bag module to the instrument panel, from a front side (engine side) of the instrument panel, and to carry out the assembly operation of the air bag module by placing upside down. Accordingly, it is possible to improve the flexibility of the assembly operation, and to efficiently utilize the excellent characteristic of the air bag module according to the embodiments of the present invention.

When a collision detecting section senses a collision of the vehicle, inflator4discharges the high pressure gas from gas discharging holes4binto air bag6. Air bag6initiates to inflate, and strongly pushes cover panel12upward from below. Consequently, cover panel12tears upwards at tear lines2f, and air bag6is deployed to the occupant.

Air bag6strongly pushes cover panel9upwards from below at the inflation thereof. At this time, air bag6tend to inflate downwards by the reaction of the upward push of air bag6. However, base plate9made of sheet metal and backup member8hanging between frame portions12aof cover panel12are disposed below air bag6, and accordingly prevent air bag6from inflating downwards. Therefore, it is possible to tear cover panel12surely, and to deploy air bag6on the passenger side.

FIGS. 6,7and8show one of fixing portions12jand mounting portion8dof backup member8fixed to frame portion12aof cover panel12in a first practical example according to the first embodiment of the present invention. A plurality of substantially U-shaped fixing portions12jare provided on the outer surface of frame portion12ato protrude outwards.

Fixing portions12jare arranged at intervals identical to the intervals of recessed portions8eformed between the adjacent two of mounting portions8dof backup member8. Each fixing portion12jis formed with a through hole12k. Through holes12kextend horizontally in a line with one another. Each retaining rod14passes through through holes12kand mounting portions8d, and fixes mounting portions8dof backup member8to frame portion12a.

In the apparatus according to the first practical example, each retaining rod14is supported by fixing portions12jnot to move. Accordingly, it is possible to omit rivets15for fixing retaining rod14to frame portions.

FIGS. 9 and 10show one of fixing portions12jin a second practical example according to the first embodiment. Each fixing portion12jis provided with a notch portion12mformed in a horizontal portion extending along frame portion12a. Retaining rod14is inserted from notch portions12m. Subsequently to the insertion of retaining rod14, it is possible to close notch portions12mby using heat caulking, as shown inFIG. 10. The operation of the air bag apparatuses according to the first and second practical example is substantially identical to the operation of the air bag apparatuses according to the first embodiment. Accordingly, the explanation of operation is omitted.

The air bag apparatus according to the first embodiment employs disc type inflator4, and however it is possible to employ a bomb type (cylindrical) inflator4laid on base plate9, as shown inFIG. 11. Overall height of air bag module1with cylindrical inflator4becomes slightly higher than overall height of air bag module1with disc-shaped inflator4. However, there are not provided the case and the retainer as conventional apparatus, and it is possible to reduce the size, the weight and the thickness of the air bag apparatus.

FIGS. 12˜14show an air bag apparatus for a driver's seat according to a second embodiment of the invention. The air bag apparatus ofFIGS. 12˜14is substantially identical to the structure of the air bag apparatus according to the first embodiment of the present invention in most aspects as shown by the use of the same reference numerals.

The air bag apparatus for the driver's seat is disposed at a center portion of a steering wheel (not shown), and accordingly cover panel12is in the form of a square, as shown inFIG. 12. Portions to which spokes are mounted are protruded outward.

Frame portion12ais provided on the back surface of cover panel12to protrude. Air bag6, retainer3, backup member8, base plate9, and inflator4are inserted from below, inside frame portion12aby the same manner as the first embodiment of the present invention, and thus air bag module1is assembled.

In air bag module1described above, the bottom is portion of base plate9is fixed, by fastening members (not shown), to mounting seat portions (not shown) provided on the steering wheel, and air bag module1is mounted to substantially center portion of the steering wheel. When air bag6is inflated by the high pressure gas discharged from inflator4at the collision of the vehicle, cover panel12is deployed by tearing at tear lines12f, as shown inFIG. 13. The inflated air bag6is deployed to the driver, as shown inFIG. 14. Accordingly, it is possible to protect the driver from the impact at the collision. Moreover, there is no need for the case arranged to receive air bag6and inflator4, and accordingly it is possible to downsize the air bag apparatus, to achieve the light weight of the air bag apparatus, and to reduce the thickness of the air bag apparatus. Hence, it is possible to reduce moment of inertia of the handle, to position the air bag module at a position remote from the occupant, and to achieve the simple design.

In the air bag apparatus according to the first and second embodiments, base plate9is made of the metal material such as steel plate and steel sheet. Moreover, it is possible to use resin material (fiberglass reinforced nylon 66, polysulfone, PPS resin, and so on) with high rigidity, designating as an engineering plastic, and to form base plate9with reinforcements such as ribs and so on, by injection molding and transfer molding.

In the air bag apparatus according to the first and second embodiments of the invention, the rigid base plate supports the reaction force acting in the downward direction at the time of inflation of the air bag, and concurrently the flexible panel restricts the air bag from inflating in the non-inflation direction. Accordingly, it is possible to certainly deploy the air bag on the occupant's side. Moreover, there is no need for the case arranged to receive the air bag and the inflator, and it is possible to reduce the size, the weight, and the thickness of the air bag apparatus. It is suitable for the air bag apparatus and so on for protecting the occupant from the impact at the collision of the vehicle.

The air bag apparatus according to the embodiments of the present invention includes a folded air bag, an inflator arranged to discharge a high pressure gas into the air bag at a collision of the vehicle, and a container member receiving the air bag, covering a non-deployment side of the air bag, and retaining the inflator. The container member includes a rigid base plate supporting the inflator and the air bag, covering one part of the non-deployment side of the air bag, and supporting a reaction force of the air bag at a deployment of the air bag, and a flexible panel including a connecting portion connected with the base plate, covering the other part of the non-deployment side of the air bag, and being arranged to restrict inflation of the air bag on the non-deployment side at the deployment of the air bag.

By the above described arrangement, the base plate supports the reaction force acting in the non-deployment direction at the time of the inflation of the air bag. The flexible panel restricts the air bag from inflating in the non-deployment direction. Accordingly, it is possible to deploy the air bag on the occupant's side surely, and to improve the reliability of the air bag apparatus.

Moreover, there is no need for a large case to receive the air bag and the inflator, and it is possible to achieve the miniaturization, the weight reduction, and the thickness reduction of the air bag apparatus. Accordingly, it is possible to easily install in the instrument panel limited in installation space by various electronic devices and so on. Moreover, it is possible to further reduce the thickness of the air bag by using the disc type inflator and so on, and to install in the instrument panel easily. For simple structure in which the narrow width base plate and the backup member cover the lower side of the air bag, it is possible to reduce the cost of the air bag apparatus.

In the air bag apparatus according to the embodiments of the invention, the flexible panel is made of a woven fabric.

By the arrangement described above, it is possible to form a thin, flexible and hard backup member, to reduce the cost of the component, and to reduce the cost of the air bag apparatus.

In the air bag apparatus according to the embodiments of the invention, the air bag apparatus includes a cover panel covering a deployment side of the air bag, and being arranged to form a deployment door at the deployment of the air bag by tearing along tear lines. The base plate includes a base connecting portion connected with the cover panel. The flexible panel includes a panel connecting portion connecting with the cover panel, and the flexible panel spreads between the connecting portion and the panel connecting portion.

By the arrangement described above, the rigid base plate supports the reaction force acting in the non-deployment direction. Concurrently, the flexible panel spreading between the connection portion and the panel connecting portions of the cover panel restricts the air bag apparatus for inflating in the non-deployment direction at the inflation of the air bag. Accordingly, it is possible to deploy the air bag to the passenger's side, and to improve the reliability of the air bag apparatus.

Moreover, the case with large bulk for receiving the air bag and inflator does not need. Accordingly, it is possible to reduce size, weight, and thickness of the air bag apparatus. The air bag apparatus can be installed in the instrument panel significantly limited in installation space for various electrical components and so on. Moreover, it is possible to further reduce a thickness of the air bag apparatus by using the disc type inflator and so on. It is possible to reduce the cost of the air bag apparatus for the simple structure which the narrow width base plate and backup member covers the lower side of the air bag.

In the air bag apparatus according to the embodiments of the invention, the tear lines includes a lateral tear line extending from a first end to a second end, a first longitudinal tear line connected with the first end of the lateral tear line, and a second longitudinal tear line connected with the second end of the lateral tear line. The base connecting portion of the base plate is located at a position near one of the first end and the second end of the lateral tear line.

By the arrangement described above, the force for the tearing is concentrated to the base connection portion around the base plate mounting portion with high strength. Accordingly, it is possible to perform the deployment operation of the air bag apparatus stably, smoothly.

In the air bag apparatus according to the embodiments of the invention, the air bag apparatus includes a reinforcement member provided at an outer circumference of portions defining the deployment door of the cover panel.

By the arrangement described above, the reinforcement members reinforce the outer circumference of portion defining the deployment door of the cover panel. Accordingly, it is possible to suppress the deformation of the cover panel in the up-down direction. Moreover, it is possible to restrain the cover panel from raising in the deployment direction at the inflation of the air bag, and to tear the tear lines surely.

In the air bag apparatus according to the embodiments of the invention, the air bag apparatus includes an instrument panel having a body member; the body member of the instrument panel includes an air bag apparatus mounting portion to which the air bag is mounted, and a mounting seat portion being provided in the air bag apparatus mounting portion. The base plate is mounted through the mounting seat portion to the body member by a fastening member. The base plate supports the reaction force of the air bag with the body member at the deployment of the air bag.

In the air bag apparatus according to the embodiments of the invention, the air bag apparatus mounting portion includes an opening portion. The cover panel is mounted to the opening portion of the air bag apparatus mounting portion so that a surface of the cover panel forms an integral surface with a surface of the instrument panel.

By the arrangement described above, it is possible to receive the air bag apparatus from the opening portion to the air bag apparatus mounting portion, in a state in which the flexible panel is shortened by the press. Even in a case in which the installation space for the air bag is limited for the installation of the various electrical devices and so on, it is possible to carry out the mounting operation of the air bag apparatus readily.

Moreover, the base plate is fixed on the mounting seat portions of the instrument panel, and the strength of the base plate increases by the rigidity of the base plate. Accordingly, it is possible to further achieve the simplicity and the light weight of the base plate, and to achieve the stable deployment characteristic of the air bag.

In the air bag apparatus according to the embodiments of the invention, the rigid base plate supports the reaction force acting in the downward direction at the inflation of the air bag, and concurrently the flexible panel restricts the air bag for inflating in the non-inflation direction. Accordingly, it is possible to deploy the air bag on the occupant's side surely. There is no need for the case to receive the air bag and the inflator. Accordingly, it is possible to reduce the size, the weight, and the thickness of the air bag.

This application is based on a prior Japanese Patent Application No. 2005-103623. The entire contents of the Japanese Patent Application No. 2005-103623 with a filing date of Mar. 31, 2005 are hereby incorporated by reference.