Patent Description:
In order to protect passengers in the event of a vehicle collision, it is well known that vehicles are equipped with one or a plurality of airbags. These airbags include, for example, various forms such as: a so-called driver airbag which expands from near the center of the steering wheel of an automobile so as to protect the driver; a curtain airbag which deploys downward along the inner side of a window of the automobile so as to protect passengers during collisions in the transverse direction of the vehicle, as well as when overturning and during rollover accidents; and a side airbag which is deployed between the passenger and a side panel so as to protect the passenger upon impact in the transverse direction of the vehicle.

In this case, the driver airbag apparatus must be housed in a limited space within the steering wheel and is required to compress the airbag into a compact size. There is also a need to quickly and assuredly restrain the driver at the initial stage in which an airbag apparatus has been actuated. Document <CIT> discloses an air bag apparatus according to the preamble of claim <NUM>.

The present invention has been created in view of the abovementioned problem, with an object of providing an airbag apparatus capable of quickly and assuredly restraining a passenger. In particular, an object of the present invention is to provide an airbag apparatus capable of quickly and assuredly restraining a passenger at the initial stage of deploying an airbag. Another object of the present invention is to provide an innovative method for manufacturing an airbag apparatus which helps to reduce manufacturing costs by simplifying the compression step of the airbag.

In order to solve the abovementioned problem, an airbag apparatus according to claim <NUM> is provided.

Herein, a "compressed body" means an airbag mass which is formed by crumpling the airbag in order to form the airbag into a desired compressed shape without being regularly folded or rolled. That is, this means that a compression step having regularity such as folding and rolling may be included; however, the main part of the formed compressed body must minimally include a mass which is irregularly collapsed and molded.

In this manner, the configuration is such that the airbag is housed in the form of a compressed body which is simply compressed, with no need for a complicated operation including folding the airbag many times along a predetermined fold line and rolling the airbag so that the center does not shift, making it possible to significantly simplify the manufacturing process.

Moreover, because the airbag is housed in the form of a compressed body, the airbag is quickly and smoothly deployed when the airbag apparatus is actuated. Meanwhile, when the airbag is folded and rolled into a bellows shape, as in an existing method, the airbag may become hooked at any location, preventing it from being smoothly deployed when the airbag is expanded and deployed.

The compressed body includes:
a vertical compressed part which collapses in the direction vertical to the surface that is horizontal to the rim of the steering wheel on the inflator side of the airbag; and a horizontal compressed part which collapses along the surface that is horizontal to the rim at least on the distal side in the deployment direction of the vertical compressed part of the airbag.

Note that in the following description of the compression step and the deployment operation of the airbag, "horizontal" basically refers to the direction parallel to (along) the surface of the rim, while "vertical" basically refers to the direction vertical to the surface. In addition, on the plane parallel to the surface of the rim (in the horizontal direction), the abdomen of the passenger or the downward direction of the vehicle is the "bottom" side, while the direction facing the head side of the passenger or the top side of the vehicle is the "top" side. That is, viewing the steering wheel as a clock face, the <NUM> o'clock direction is regarded as the "top," while the <NUM> o'clock direction is regarded as the "bottom. " Moreover, the passenger side is the "top" side and the steering column side is the "bottom" side in the direction vertical to the surface of the rim (in the vertical direction).

By forming a vertical compressed part which vertically collapses from the inflator side, the inflation gas released from the inflator first causes the vertical compressed part to be deployed towards the passenger side, such that the front surface of the airbag can approach or contact the passenger at the very initial stage, making it possible to quickly restrain the passenger from moving forward (in the steering wheel direction).

Moreover, in addition to the benefits of quickly restraining the forward movement of the passenger due to the presence of the vertical compressed part, the horizontal compressed body is quickly and smoothly deployed. That is, because the vertical compressed part is initially deployed, when the horizontal compressed part attempts to be horizontally deployed along the surface of the rim of the steering wheel, the horizontal compressed part has already been sufficiently pushed forward. As a result, the horizontal compressed part is smoothly deployed in the horizontal direction without any interference inside the steering wheel.

The end surface of the vertical compressed part opposite the inflator preferably reaches the outside of the rim at the initial stage of deploying the airbag. This means that the deployment (stretching) stroke of the vertical compressed part in the vertical direction is sufficiently increased. As described above, when the airbag starts to be deployed, the vertical compressed body is first deployed towards the passenger side, at which point, when the front surface of the vertical compressed part reaches the outside of the rim and the horizontal compressed part attempts to be horizontally deployed along the surface of the rim of the steering wheel, there is no object interfering in the horizontal direction, making it possible to more assuredly and smoothly deploy the airbag (horizontal compressed part) in the horizontal direction.

The airbag can be molded into a generally circular truncated cone shape by: a generally circular back panel coupled to the inflator; a generally circular front panel which faces the passenger upon deploying the airbag and has a larger diameter than the back panel; and a side panel which is coupled to the back panel and the front panel.

Alternatively, the airbag can be formed by a generally circular back panel coupled to the inflator as well as by a generally circular front panel which faces the passenger upon deploying the airbag.

A portion of the front panel facing the passenger side preferably remains exposed to the outside upon housing the airbag. That is, the entire upper surface (passenger side) of the front panel is preferably at least partially out of the surface without entering the interior in the compression step. Such a configuration allows the passenger to be supported on the "flat surface" by the exposed front panel when the vertical compressed part is deployed at the initial stage of deploying the airbag, thereby improving the passenger restraining performance.

Moreover, the exposed part of the front panel preferably includes at least the front panel central region. Further, the vertical compressed part is preferably formed so as to include the central part of the front panel and the back panel.

By aligning the center of the back panel with the center of the front panel in the vertical direction, the vertical compressed part is easily linearly deployed in the vertical direction, making it possible to improve the deployment speed and stabilize the deployment behavior. That is, for example, situations in which the vertical compressed body meanders before being deployed can also be avoided.

Alternatively, the central axis in the vertical direction of the vertical compressed part can pass through the central part of the back panel, with the central part of the front panel capable of being formed so as to be shifted from the central axis. At this time, the central part of the front panel is preferably provided so as to be shifted in a more downward direction of the vehicle than the central axis of the vertical compressed part. Such a configuration allows the airbag to deploy and enter more largely and quickly in the abdominal direction of the passenger than in the head direction thereof at the stage when the horizontal compressed part of the airbag starts to deploy.

A tether controlling the deployed shape of the airbag can be provided inside the airbag. In this case, the tether can include: a generally circular base part fixed to the central part of the front panel, and at least two string parts extending from the base part to the back panel. Herein the end part of the string part can be coupled to the vicinity of the periphery of the inflator. The presence of the tether further stabilizes the deployment behavior of the airbag.

The airbag apparatus can further include a rectifying fabric (which changes the direction of flow of gas ejected from the inflator) within the airbag, wherein a portion of the rectifying fabric can be configured so as to be disposed in the vicinity of the central part of the front panel. This rectifying fabric includes: a top plate fabric which is disposed in the vicinity of or in contact with the front panel when the airbag is compressed and housed, and a side surface part which extends from the top plate fabric to the back panel. An opening is provided on this side surface part so as to allow flow in the horizontal direction while the inflation gas ejected from the inflator is repelled by the top plate fabric. In addition, the length in the vertical direction of the side surface part is set to a length such that the vertical compressed part protrudes slightly from the horizontal surface of the passenger side end part of the rim of the steering wheel (the plane including the surface of the rim on the passenger side; hereinafter, referred to as the "rim surface") at the initial stage of the deployment. Moreover, when a portion of the rectifying fabric is disposed near the center of the front panel, the rectifying fabric extends in the vertical direction along with the vertical compressed part at the initial stage of deploying the airbag, protruding slightly from the rim surface of the steering wheel. In this manner, the presence of the rectifying fabric during the initial deployment of the airbag causes most of the pressure of the inflation gas to be directed vertically upward and acts to push the vicinity of the center of the inner surface of the front panel vertically upward, thereby promoting the upward vertical deployment of the airbag during the initial deployment of the airbag. In addition, when the initial deployment in the vertical direction proceeds, the inflation gas flows from an opening (provided on the side surface of the rectifying fabric) towards the horizontal direction in the airbag. This increases the force with which the airbag is horizontally deployed. The airbag is deployed from the part (which has already been deployed in the vertical direction to protrude slightly from the rim surface) so as to spread along the rim surface in the horizontal direction.

The second aspect of the present invention is a method for manufacturing an airbag apparatus according to claim <NUM>.

The step of forming the compressed body includes:
collapsing a part of the airbag on the inflator side in the direction vertical to the surface that is horizontal to the rim of the steering wheel to form a vertical compressed part, and collapsing the airbag along the surface that is horizontal to the rim at least on the distal side in the deployment direction of the vertical compressed part of the airbag to form a horizontal compressed part.

In the step of forming the vertical compressed part, the compression range of the vertical compressed part is preferably set such that the end part of the vertical compressed part opposite the inflator reaches the outside of the rim upon deploying the airbag.

The airbag can be molded into a generally circular truncated cone shape by: a generally circular back panel coupled to the inflator, a generally circular front panel which faces the passenger upon deploying the airbag and has a larger diameter than the back panel, and a side panel which is coupled to the back panel and the front panel. In addition, the vertical compressed part can be formed by a portion of the back panel and the side panel, with the horizontal compressed part capable of being formed by the remaining part of the side panel along with the front panel.

Alternatively, the airbag can be formed by a generally circular back panel coupled to the inflator as well as by a generally circular front panel which faces the passenger upon deploying the airbag. In addition, the vertical compressed part can be formed by the back panel, with the horizontal compressed part capable of being formed by the remaining part of the back panel along with the front panel.

In the step of forming the horizontal compressed part, at least a portion of the surface of the front panel preferably remains exposed to the outside.

The vertical compressed part can be formed so as to include the central part of the front panel and the back panel. Alternatively, the central axis in the vertical direction of the vertical compressed part can pass through the central part of the back panel, with the central part of the front panel capable of being formed so as to be shifted from the central axis. At this time, the central part of the front panel is preferably provided so as to be shifted in a more downward direction of the vehicle than the central axis of the vertical compressed part.

Embodiments for carrying out the present invention will hereinafter be described with reference to the accompanying drawings. <FIG> is a cross sectional view illustrating the structure of an airbag apparatus according to an example of the present invention. An airbag apparatus <NUM> according to the present example includes: a disk shaped (cylindrical) inflator <NUM> which generates inflation gas; and an airbag <NUM> which is deployed by the inflation gas to protect a passenger. The inflator <NUM> is fixed to a housing <NUM> via a retainer <NUM>. The housing <NUM> is coupled to a cover <NUM> which covers the central part of the steering wheel in which the airbag apparatus <NUM> is housed.

As will hereinafter be described in detail, the airbag <NUM> is housed as a compressed body which is compressed to collapse. Herein, the "compressed body" means an airbag <NUM> mass which is formed by crumpling the airbag in order to form the airbag into a desired compressed shape without being regularly folded or rolled. That is, this means that a compression step having regularity such as folding and rolling may be included; however, the main part of the formed compressed body must minimally include a mass which is irregularly collapsed and molded.

The compressed body (<NUM>) according to the airbag includes: a vertical compressed part 14V which collapses in the direction vertical to the surface that is horizontal to a rim <NUM> of the steering wheel on the inflator <NUM> side of the airbag <NUM>; and a horizontal compressed part <NUM> which collapses parallel to the surface that is horizontal to the rim <NUM> at least on the distal side in the deployment direction of the vertical compressed part 14V of the airbag <NUM>.

Note that in the following description of the compression step and the deployment operation of the airbag, "horizontal" basically refers to the direction H parallel to the surface of the rim (rim surface), while "vertical" basically refers to the direction V vertical to the surface.

<FIG> is a schematic perspective view and <FIG> is a schematic cross sectional view, with both figures illustrating the panel structure of an airbag <NUM> employed in the airbag apparatus <NUM> according to Example <NUM>. <FIG> are plan views each illustrating the shape of each panel configuring the airbag <NUM> according to Example <NUM> of the present invention.

As illustrated in <FIG> and <FIG>, the airbag <NUM> is molded into a generally circular truncated cone shape by: a circular back panel <NUM> coupled to the inflator <NUM> via a retainer ring <NUM>; a front panel <NUM> which is molded into a circular shape having a larger diameter than the back panel <NUM> and faces the passenger upon deploying the airbag <NUM>; and a side panel <NUM> coupled to the back panel <NUM> and the front panel <NUM>. Note that an opening <NUM> in which the inflator <NUM> is housed is formed at the center of the back panel <NUM>.

As illustrated in <FIG>, the side panel <NUM> cuts into a rectangular (band shaped) member to smoothly form a truncated cone shaped side surface. Note that instead of the side panel <NUM>, as illustrated in <FIG>, a side panel <NUM> with a sector (an "annular sector" or "hollow sector," to be precise) can be employed.

As illustrated in <FIG>, a tether <NUM> controlling the deployed shape of the airbag <NUM> is provided inside the airbag <NUM>. Note that in <FIG>, the structure of the interior of the airbag <NUM> including the tether <NUM> is omitted. Moreover, in <FIG>, two parallel thin lines are illustrated as sewing locations.

The tether <NUM> includes: a generally circular base part 28a concentrically disposed and fixed to the central part of the front panel <NUM>; and at least two string parts 28b, 28c extending from the base part 28a towards the back panel <NUM> side. The end parts of the string parts 28b, 28c are coupled to the vicinity of the periphery of the inflator <NUM>. One end of the reinforcing fabrics 30a, 30b is coupled to the string parts 28b, 28c of the tether <NUM> by sewing, while the other end of the reinforcing fabrics 30a, 30b is coupled to the inner surface of the front panel <NUM> by sewing.

The presence of the tether <NUM> further stabilizes the deployment behavior of the airbag <NUM>. That is, by adjusting the inflation range (thickness) in the vertical direction, the shape (thickness, surface area, etc.) of the airbag <NUM> can be adjusted upon the full deployment thereof.

<FIG> are explanatory views illustrating the compression step of the airbag <NUM> according to Example <NUM> of the present invention, wherein (A) to (C) are cross sectional views, while (D) is a perspective view. <FIG>, (A2), and (B) are explanatory views (cross sections) illustrating the compression step of the airbag <NUM> according to Example <NUM> of the present invention. Note that, in <FIG>, for convenience of description, the sewing location of each panel <NUM>, <NUM>, and <NUM> is illustrated as a white circle. Moreover, although the structure around the inflator <NUM> is simplified, in practice, the inflator <NUM> is fixed to the back panel <NUM> via the retainer ring <NUM> (<FIG>).

In the present example, upon compressing the airbag <NUM> from the state illustrated in <FIG> and <FIG>, first, as illustrated in <FIG>, the central part of the back panel <NUM> is lowered, while a portion of the back panel <NUM> and the side panel <NUM> is cylindrically held. For example, prior to installing the inflator in the airbag, a tubular member can be inserted from the opening <NUM> of the back panel <NUM> and pushed towards the front panel <NUM> side, thereby enabling cylindrical molding.

Next, as illustrated in <FIG> and <FIG>, the vertical compressed part 14V is molded by compressing the airbag <NUM> so as to collapse the airbag <NUM> in the vertical direction from the back panel <NUM> side towards the front panel <NUM> side. At this time, the vertical compressed part 14V is configured so as to include the central part of the front panel <NUM> and the central part of the back panel <NUM>, with the cores aligned such that the center positions thereof overlap in the vertical direction. That is, the vertical direction V preferably matches the center line C1 of the airbag.

Moreover, in the step of forming the vertical compressed part 14V, as illustrated in <FIG>, the vertical height VL of the region being compressed to form the vertical compressed part 14V is greater than the distance (depth) D1 (see <FIG>) from the bottom of the retainer ring <NUM> to the surface (rim surface) of the rim <NUM>. This is because, at the initial deployment of the airbag <NUM>, the upper surface of the vertical compressed part 14V assuredly reaches the outside of the cover <NUM>, ensuring a stroke which protrudes towards the passenger side rather than towards the rim surface.

Next, as illustrated in <FIG>, the front panel <NUM> and the side panel <NUM> other than the vertical compressed part 14V are compressed so as to collapse in the horizontal direction, such that the horizontal compressed part <NUM> is molded around the vertical compressed part 14V. The vertical compressed part 14V and the horizontal compressed part <NUM> complete the compressed body (<NUM>). Note that in the horizontal compressed step, in reality, the vertical compressed part 14V also collapses in the horizontal direction to a certain degree.

Here, in the step of forming the horizontal compressed part <NUM>, at least a portion of the surface of the front panel <NUM> remains exposed to the outside. For example, the central part 28a of the tether <NUM> and the periphery thereof are preferably seen on the surface. In the step of forming the horizontal compressed part <NUM>, for example, a push plate may be used to separately push and collapse in the X direction and the Y direction, alternately push and collapse, or simultaneously push and collapse.

As described above, in the present example, the airbag <NUM> employed is housed in the form of a compressed body which is simply compressed, with no need for any operation including repeatedly folding the airbag <NUM> along a predetermined fold line and rolling the airbag so that it is not shifted to the periphery of the core, making it possible to significantly simplify the manufacturing process.

<FIG>, and <FIG> are explanatory views illustrating the state in which the airbag <NUM> according to the present invention is deployed. Note that the deployment operation of the airbag described below is the same as those of Examples <NUM> and <NUM> described below in addition to that of Example <NUM> described above. As the inflator <NUM> is activated and the inflation gas causes the airbag <NUM> to start being deployed, as illustrated in <FIG>, at the initial stage of the deployment, the vertical compressed part 14V is initially deployed in the vertical direction and protrudes from the rim surface to push and break the cover <NUM> of the steering wheel so as to approach the passenger side. At this time, the horizontal compressed part <NUM> starts to be slightly but not significantly deployed.

In this manner, the inflation gas released from the inflator <NUM> first causes the tip part of the vertical compressed part 14V to be deployed towards the passenger side, such that the front surface of the airbag <NUM> protrudes from the rim surface at the very initial stage.

Further, in the present example, by aligning the center of the back panel <NUM> (on the small diameter side of the truncated cone) with the center of the front panel <NUM> (on the large diameter side) in the vertical direction, the vertical compressed part 14V is easily linearly deployed in the vertical direction, making it possible to improve the deployment speed and stabilize the deployment behavior. For example, this also allows situations to be avoided in which the vertical compressed body 14V meanders before being deployed.

Next, as illustrated in <FIG>, as the airbag <NUM> is deployed, the horizontal compressed part <NUM> is actively deployed, while the airbag <NUM> is deployed in the direction horizontal to the rim <NUM>. That is, after the initial deployment of the vertical compressed part 14V, the horizontal compressed part <NUM> is deployed along the rim surface so as to cover the rim <NUM>. Here, when the horizontal compressed part <NUM> attempts to be horizontally deployed along the surface of the rim <NUM> of the steering wheel, the horizontal compressed part <NUM> has already been pushed sufficiently forward due to the deployment of the vertical compressed part 14V, such that the horizontal compressed part <NUM> can be deployed without interference inside the steering wheel. This at least temporarily covers the rim <NUM> with the airbag <NUM> prior to the full deployment of the airbag <NUM>. Consequently, even if the passenger potentially approaches the steering wheel direction prior to the full deployment of the airbag <NUM> during the collision (emergency) of the vehicle, the airbag <NUM> can avoid situations in which the abdomen of the passenger directly contacts (collides with) the steering wheel. Subsequently, as illustrated in <FIG>, the full deployment of the airbag <NUM> can assuredly restrain the passenger.

<FIG> is an explanatory view (cross section) illustrating the structure and compression step of an airbag <NUM> according to Example <NUM> of the present invention. <FIG> is a plan view illustrating the shape of a front panel <NUM>(A) and a back panel <NUM>(B) used in the airbag <NUM> illustrated in <FIG>. Note that, in <FIG>, as in <FIG>, for convenience of description, the sewing location of each panel <NUM>, <NUM> is illustrated as a white circle. Moreover, although the structure around the inflator <NUM> is simplified, in practice, the inflator <NUM> is fixed to the back panel <NUM> via the retainer ring <NUM> (<FIG>). Moreover, components identical or corresponding to those of the abovementioned Example <NUM> are labeled with identical symbols, with redundant descriptions thereof omitted and with differences thereof mainly described.

In Example <NUM>, the airbag <NUM> is configured by the back panel <NUM>, the front panel <NUM>, and the side panel <NUM>. In contrast, in Example <NUM>, the airbag <NUM> is configured by the back panel <NUM> and the front panel <NUM>, with no side panels employed. In addition, as illustrated in <FIG>, a bag having a bag shape is formed by coupling the outer edge parts of the back panel <NUM> and the front panel <NUM> having generally the same diameter by sewing.

In the present example, upon compressing the airbag <NUM> from the state illustrated in <FIG>, the central part of the back panel <NUM> is first lowered, while a portion of the back panel <NUM> is cylindrically held. In this example, while the airbag <NUM> is compressed with the inflator <NUM> set in the airbag <NUM>, an axle, etc. may be passed through the opening <NUM> for an inflator so as to core the panels together prior to setting the inflator in order to center the panels together and cylindrically hold the portion of the back panel <NUM>.

Next, as illustrated in <FIG>, a vertical compressed part 214V is molded by compressing the airbag <NUM> so as to collapse the airbag <NUM> in the vertical direction from the back panel <NUM> side towards the front panel <NUM> side. At this time, as in Example <NUM>, the vertical compressed part 214V is configured so as to include the central part of the front panel <NUM> and the central part of the back panel <NUM>, with the cores aligned such that the center positions thereof overlap in the vertical direction.

Subsequently, as illustrated in <FIG>, the rest of the back panel <NUM> and the front panel <NUM> not forming the vertical compressed part 214V are compressed so as to collapse in the horizontal direction, such that a horizontal compressed part <NUM> is formed around the vertical compressed part 214V. The vertical compressed part 214V and the horizontal compressed part <NUM> complete the compressed body (<NUM>).

<FIG> is an explanatory view (cross section) illustrating the structure and compression step of an airbag according to Example <NUM> of the present invention, corresponding to <FIG> of Example <NUM>. Note that components identical or corresponding to those of the abovementioned Example <NUM> are labeled with identical symbols, with redundant descriptions thereof omitted and with differences thereof mainly described.

In Example <NUM>, a rectifying fabric <NUM> which changes the direction of flow of gas ejected from the inflator <NUM> is provided within the airbag <NUM>. For example, the rectifying fabric <NUM> includes: a top plate fabric <NUM> which is formed in a parachute shape (umbrella shape, arbor shape) so as to reflect gas (which is ejected from the inflator <NUM>) on the inner surface of the ceiling part; and a side surface part <NUM> (which extends from the top plate fabric <NUM> towards the back panel <NUM> side). The side surface part <NUM> is provided with an opening <NUM> that allows the inflation gas ejected from the inflator <NUM> to be reflected on the inner surface of the top plate fabric <NUM>, flow in the horizontal direction, and be guided in the side panel <NUM> direction (lateral direction).

As illustrated in <FIG>, in the compressed state of the airbag <NUM>, the top plate fabric <NUM> (front panel <NUM> side) of the rectifying fabric <NUM> is provided in the vicinity of the central part of the front panel <NUM>. For example, as illustrated in <FIG>, the maximum vertical height H1 of the rectifying fabric <NUM> is set to be equal to or greater than the length VL illustrated in <FIG> or D1 illustrated in <FIG>, while the vertical compressed part 14V is set to be a length so as to slightly protrude from the rim surface of the steering wheel during the initial deployment.

By setting the maximum height H1 of the rectifying fabric <NUM> in this manner, the rectifying fabric <NUM> extends in the vertical direction along with the vertical compressed part 14V at the initial stage of deploying the airbag <NUM>, with the airbag <NUM> protruding slightly from the rim surface of the steering wheel. During the initial deployment, the presence of the rectifying fabric <NUM> causes most of the inflation gas ejected from the inflator <NUM> to be oriented vertically upward such that the top plate fabric <NUM> of the rectifying fabric <NUM> acts to push the front plate fabric <NUM> of the rectifying fabric <NUM> vertically upward in the vicinity of the center of the inner surface of the front panel <NUM>, thereby promoting the upward vertical deployment of the airbag at the initial deployment of the airbag <NUM>. In addition, in order to help expand and deploy the airbag <NUM> along the rim surface in the horizontal direction, gas can be subsequently primarily released in the horizontal direction from the opening <NUM> provided on the side part <NUM> of the rectifying fabric <NUM> such that the airbag <NUM> can cover the rim surface early. This at least temporarily covers the rim <NUM> with the airbag <NUM> prior to the full deployment of the airbag <NUM>. Consequently, even if the passenger potentially approaches the steering wheel direction prior to the full deployment of the airbag <NUM> during a collision (emergency) of the vehicle, the airbag <NUM> can avoid situations in which the passenger contacts (collides with) the steering wheel. Subsequently, the airbag <NUM> can be fully deployed to assuredly restrain the passenger while further reducing damage to the passenger.

<FIG> is an explanatory view (cross section) illustrating the structure and compression step of an airbag according to Example <NUM> of the present invention, corresponding to <FIG> of Example <NUM> and <FIG> of Example <NUM>. Note that in the present example, the structure of the airbag in Example <NUM> is arranged, while components identical or corresponding to those of the abovementioned examples are labeled with identical symbols, with redundant descriptions thereof omitted and with differences thereof mainly described.

The airbag <NUM> used in Example <NUM> includes a back panel <NUM>, a front panel <NUM>, and a side panel <NUM>. In the present example, the central axis C1 in the vertical direction of a vertical compressed part <NUM> passes through the center of the back panel <NUM> and further through the center of the top plate fabric <NUM> of the rectifying fabric <NUM>. However, the central axis C1 is formed such that it does not pass through the center C0 of the front panel <NUM>, that is, the center C0 is formed so as to be shifted from the central axis C1. At this time, the central part C0 is formed so as to be shifted in the downward direction of the vehicle (the abdomen of the passenger, in the knee direction), that is, in the <NUM> o'clock direction when the steering wheel is viewed as a clock face.

<FIG>, and <FIG> are explanatory views illustrating the state in which the airbag according to Example <NUM> of the present invention is deployed. As the inflator <NUM> is activated and the inflation gas causes the airbag <NUM> to start being deployed, as illustrated in <FIG>, at the initial stage of deployment, the vertical compressed part 414V is initially deployed in the vertical direction and protrudes from the rim surface to push and break the cover <NUM> of the steering wheel so as to approach the passenger. The operations described above are the same as those of Examples <NUM> to <NUM> described above.

Next, as illustrated in <FIG>, as the airbag <NUM> is deployed, the horizontal compressed part <NUM> is actively deployed, with the airbag <NUM> deployed in the direction horizontal to the rim <NUM>. That is, after the initial deployment of the vertical compressed part 414V, the horizontal compressed part <NUM> is deployed along the rim surface so as to cover the rim <NUM>. Here, when the horizontal compressed part <NUM> attempts to be horizontally deployed along the surface of the rim <NUM> of the steering wheel, the horizontal compressed part <NUM> has already been sufficiently pushed forward due to the deployment of the vertical compressed part 414V, such that the horizontal compressed part <NUM> can be deployed without interference inside the steering wheel. In this respect, it is also the same as those of Examples <NUM> to <NUM> described above.

Claim 1:
An airbag apparatus housed within a steering wheel, comprising:
an inflator (<NUM>) which generates inflation gas; and
an airbag (<NUM>) deployed by the inflation gas to protect a passenger;
wherein the airbag (<NUM>) is housed as a compressed body which is compressed such that the compressed body minimally includes a mass which is irregularly collapsed and molded, and
wherein the compressed body comprises: a vertical compressed part (14V) which is collapsed in the direction vertical to the surface that is horizontal to the rim (<NUM>) of the steering wheel on the inflator side of the airbag (<NUM>);
characterized in that the compressed body further comprises a horizontal compressed part (<NUM>) which is collapsed along the surface that is horizontal to the rim (<NUM>) at least on the distal side in the deployment direction of the vertical compressed (14V) part of the airbag (<NUM>).