Patent Description:
In the recent years, an airbag device is mostly equipped with a vehicle as the standard equipment. The airbag device is a safety device being operated in an emergency such as a vehicle collision and protects an occupant by expanding and deploying an airbag cushion (simply described as a "cushion" below) with a gas pressure so as to receive the occupant.

There are various kinds of airbag devices according to the installation positions and the use. For instance, a front airbag device is provided at a center of a steering wheel so that a driver can be protected from a collision occurred from the forward and backward directions. In addition, in order to protect an occupant from an impact in a vehicle width direction by such as a side collision, a curtain airbag device is provided near a ceiling above a side window and a side airbag device is provided at a side part of a seat.

For instance, a vehicle seat that is equipped with a side airbag device is disclosed in Patent Document <NUM>. In the technology in Patent Documents <NUM>, the folded side airbag <NUM> is provided inside the seatback <NUM> and at an outside of the side frame 16A in the vehicle width direction, that is, at an opposite side with respect to an occupant.

Patent Document <NUM>: <CIT>. Further vehicle seats equipped with side airbags are known from the documents <CIT>, <CIT>, <CIT> and <CIT> <CIT> discloses a side airbag device with the technical features of the preamble of claim <NUM>.

At the present time, with respect to a side airbag device, further improvement of an occupant restraint force is required. In order to improve the occupant restraint force, it is considered to take the measures that, for instance, a deployment position of an airbag cushion is set at a position being closer to an occupant. However, as shown in, for example, <FIG> and others in Patent Document <NUM>, a seat pad that is obtained by utilizing such as a urethane material is filled inside the seatback. Therefore, because a storage space of the airbag cushion of the side airbag device is extremely limited, it is difficult to devise methods for the improvement of the occupant restraint force.

The present invention attempts to solve these problems. An object of the present invention is to provide a side airbag device that can be efficiently stored inside a seatback and can also improve the occupant restraint force.

In order to solve the above problems, a configuration of a side airbag device according to the present invention includes: a seat frame that is along a side surface of a seatback of a vehicle seat, the seat frame being built in the seatback; an inflator that is attached to an occupant side of the seat frame; and an airbag cushion that receives a gas from the inflator so as to be expanded and deployed. The airbag cushion includes: an inner side expansion part that is stored at the occupant side of the seat frame by being wound and the inner side expansion part is connected to the inflator; and an outer side expansion part that is continuously provided with the inner side expansion part, the outer side expansion part is stored by being wound at an opposite side of the seat frame with respect to the occupant side, and the outer side expansion part receives the gas from the inner side expansion part so as to be expanded and deployed. The airbag cushion has a first folded-back part that is located between the inner side expansion part and the outer side expansion part, and the airbag cushion is folded back along a front edge of the seat frame with respect to the first folded-back part. According to this configuration, the airbag cushion can be efficiently stored in the seatback. The inner side expansion part explained above include an inner contact part that directly comes in contact with the seat frame or indirectly comes in contact with the seat frame by sandwiching a cover between the inner contact part and the seat frame and extends from a position to which the inflator is attached toward the front edge of the seat frame, a third folded-back part with which the inner side expansion part is folded back from a front edge at the vehicle front side of the inner contact part toward the vehicle rear, and an inner folding part that further extends from the third folded-back part toward the front edge.

According to the configuration explained above, because the airbag cushion is stored by being divided into at the occupant side and at the opposite side of the occupant with respect to the seat frame, the limited space of the inside of the seatback can be efficiently utilized. As a result, it can be applied to various vehicle seats so as to have a high versatility. Further, because the installation space can be made narrow, the miniaturization of the vehicle seat can also be realized.

In addition, because the airbag cushion that has the configuration explained above starts to be expanded from the inner side expansion part that is stored at the occupant side of the seat frame, a reaction force directed from the seat frame toward the occupant side can be obtained at an early stage. The inner side expansion part is also the basis of the airbag cushion, and according to the configuration explained above, the airbag cushion after being expanded is also located at the position being closer to the occupant. Therefore, according to the configuration explained above, the occupant restraint force can be improved.

According to the configuration explained above, when the gas is flown into the inner side expansion part, due to the expansion of the inner side contact part and due to the expansion so as to make the third folded-back part to disappear, the inner side contact part pushes the seat frame. As a result, the inner side contact part becomes possible to efficiently obtain the reaction force directed from the seat frame toward the occupant side. In particular, the inner side expansion part is located at the upstream side of the flow of the gas in the airbag cushion. Therefore, according to the configuration explained above, because the reaction force directed toward the occupant side can be obtained at an initial stage of the expansion and deployment of the airbag cushion, the acceleration of the expansion and deployment of the entirety of the airbag cushion and the further improvement of the occupant restraint force can be realized. In the side airbag device, the outer side expansion part is stored in the seatback in a state in which the outer side expansion part directly comes in contact with the seat frame or a state in which the outer side expansion part indirectly comes in contact with the seat frame by sandwiching another member between the outer side expansion part and the seat frame. According to this configuration, when the outer side expansion part is expanded, the reaction force can be efficiently obtained by the seat frame, and an acceleration of the expansion and deployment and the improvement of the occupant restraint force can be realized.

The outer side expansion part explained above may include an outer contact part that directly comes in contact with a predetermined area of the seat frame extending from the front edge of the seat frame toward a vehicle rear or indirectly comes in contact with the predetermined area by sandwiching another member between the outer contact part and the predetermined area, and a second folded-back part with which the outer side expansion part is folded back from a rear end at a vehicle rear side of the outer contact part toward a vehicle front. According to this configuration, when the gas is flown into the outer side expansion part, due to the expansion of the outer side contact part and due to the expansion so as to make the second folded-back part to disappear, the outer side expansion part pushes the seat frame. As a result, the outer side expansion part becomes possible to efficiently receive the reaction force by the seat frame. Further, since the outer side expansion part is expanded and deployed by receiving the reaction force by the seat frame, the acceleration of the expansion and deployment of the entirety of the airbag cushion and the improvement of the occupant restraint force can be realized.

The outer side expansion part explained above may include an upstream region that extends from the front edge of the seat frame toward the vehicle rear, and a downstream region that is stored between the upstream region and the seat frame. The downstream region receives the gas from the upstream region so as to be expanded. According to this configuration, when the gas is flown from the upstream region to the downstream region, the downstream region pushes the seat frame. As a result, the reaction force can also be efficiently obtained by the seat frame, and the acceleration of the expansion and deployment and the improvement of the occupant restraint force can be realized.

The outer side expansion part explained above also include a part that is wound. According to this configuration, the outer side expansion part can be efficiently stored in the limited space of the inside of the seatback.

The inner side expansion part explained above may also include a part that is folded in bellows. According to this configuration, the inner side expansion part can also be efficiently stored in the limited space of the inside of the seatback.

With respect to the side airbag device, a front edge of the seat frame explained above may be rounded. According to this configuration, the airbag cushion can be stored in the seatback and operated without being damaged.

With respect to the seat frame explained above, a thickness in a vehicle width direction of the front edge of the seat frame may be larger than a thickness in the vehicle width direction of a region rearwardly located from the front edge. According to this configuration, the airbag cushion can also be stored in the seatback and operated without being damaged.

According to the present invention, it becomes possible to provide a side airbag device that can be efficiently stored in a seatback and can also achieve the improvement of the occupant restraint force.

<NUM> - Side Airbag Device, <NUM> - Seat, <NUM> - Seatback, <NUM> - Seat Frame, <NUM> - Cushion, <NUM> - Inflator, <NUM> - Stud Bolt, <NUM> - Inner Side Expansion Part, <NUM> - First Folded-back Part, <NUM> - Outer Side Expansion Part, <NUM> - Front Edge of Seat Frame, <NUM> - Seat Pad, <NUM> - Side Surface of Inner Side of Seat Frame, <NUM> - Reaction Force that Inner Side Expansion Part Obtains, <NUM> - Cover, <NUM> - Side Surface of Outer Side of Seat Frame, <NUM> - Reaction Force that Outer Side Expansion Part Obtains, <NUM> - Force for Making Folded-back between Inner Side Expansion Part and Outer Side Expansion Part to Disappear, <NUM> - Cover, <NUM> - Cushion of First Variation, <NUM> - Outer Side Expansion Part of First Variation, <NUM> - Outer Side Contact Part, <NUM> - Second Folded-back Part, <NUM> - Cushion of Second Variation, <NUM> - Outer Side Expansion Part of Second Variation, <NUM> - Upstream Region, <NUM> - Downstream Region, <NUM> - Cushion of Third Variation, <NUM> - Outer Side Expansion Part of Third Variation, <NUM> - Cushion of Fourth Variation, <NUM> - Inner Side Expansion Part of Fourth Variation, <NUM> - Cushion of Fifth Variation, <NUM> - Inner Side Expansion Part of Fifth Variation, <NUM> - Inner Folding Part, <NUM> - Inner Side Contact Part, <NUM> - Third Folded-back Part, <NUM> - Seat Frame of Variation, and <NUM> - Front Edge of Variation.

Preferred embodiments of the present invention will be explained in detail below with reference to the attached drawings, while the embodiment shown in <FIG> is covered by the invention and the embodiments shown in the <FIG> and <FIG> are not covered by the invention. The dimensions, materials, other concrete numerical values, and other that are disclosed in the embodiments are merely examples for facilitating understanding of the invention, and unless otherwise stated, they do not limit the present invention. Further, in the specification and the drawings, with respect to the elements having substantially the same functions and configurations, redundant explanations are omitted by accompanying the same reference numerals. Further, the elements that are not directly related to the present invention are not shown in the drawings.

<FIG> is a diagram that exemplarily shows a side airbag device <NUM> according to an embodiment of the present invention. <FIG> exemplarily shows the side airbag device <NUM> and a vehicle seat (a seat <NUM>) that is located on the left side of a vehicle and in which the side airbag device <NUM> is utilized when viewed from an inner side (a compartment side) in a vehicle width direction. With respect to <FIG> and all other drawings according to the present invention, the vehicle front and rear (longitudinal) direction denotes the arrows F (Forward) and B (Back), the vehicle width direction that corresponds to the left and right respectively denotes the arrows L (Left) and R (Right), and the vehicle vertical direction denotes the arrows U (Up) and D (Down).

In <FIG>, with respect to a seatback <NUM> of a seat <NUM>, only a seat frame <NUM> is exemplarily shown by omitting a cover and a seat pad (for instance, a urethane material). The seat frame <NUM> is a member that becomes a framework of the seatback <NUM> and is built in the seatback <NUM> along a side surface and an upper edge of the seatback <NUM>.

An airbag cushion (a cushion <NUM>) is a part being formed in a bag shape by which an occupant is received upon an emergency event such as the occurrence of an impact on the vehicle, and is expanded and deployed in a flat shape toward a side of the occupant (not shown) that sits on the seat <NUM> by receiving a gas from an inflator <NUM>. The cushion <NUM> is formed in the bag shape by sewing or adhering two stacked base cloths that configure a periphery of the cushion <NUM>, or by spinning and weaving by utilizing the OPW (One-Piece Woven).

In the present embodiment, the cushion <NUM> is built in the vicinity of the side portion of the seat <NUM>. The cushion <NUM> is installed on the seat frame <NUM> via the inflator <NUM>. In particular, in the present embodiment, the cushion <NUM> and the inflator <NUM> are installed at a side of a center of the seat frame <NUM> in the vehicle width direction of the seat <NUM>, i.e., the occupant side of the seat frame <NUM>.

The inflator <NUM> is a gas generator and operates by receiving an operation signal that is transmitted from the vehicle side at the occurrence of the impact so as to supply the gas to an inside of the cushion <NUM>. The inflator <NUM> that is adopted in the present embodiment is a cylinder type (a cylindrical type) and is installed at a vehicle rear side of the inside of the cushion <NUM> in a state in which the longitudinal direction of the inflator <NUM> aligns with the vertical direction. A stud bolt <NUM> (refer to <FIG>) is provided at the inflator <NUM>. The stud bolt <NUM> is fastened to the seat frame <NUM> by penetrating through the cushion <NUM>.

There are some kinds of the inflators that are spread through the market at the present time, such as a model in which a gas generating agent is filled and a gas is generated by burning the gas generating agent, a model in which a compressed gas is filled and a gas is supplied without generating heat, and a hybrid model in which a combustion gas and a compressed gas are used. Any kinds of the inflators can be utilized as the inflator <NUM>.

Fig. 1B is a diagram that exemplarily shows a state in which the cushion <NUM> shown in <FIG> is stored. As exemplarily shown in Fig. 1B, the airbag cushion <NUM> is stored inside the seatback <NUM> in the state in which its size is reduced by being wound and folded. In the present embodiment, the cushion is stored as the cushion sandwiches the seat frame <NUM> so as to be efficiently stored in the limited space of the inside of the seatback <NUM>.

With respect to the cushion <NUM> being in a stored state, its periphery is covered by a cover <NUM>. The cover <NUM> maintains the state of the cushion <NUM> inside the seatback <NUM> in which the size of the cushion <NUM> is reduced by being wound and folded. The cover <NUM> can be realized in various forms, such as a configuration of the wrapping by the same material as a base cloth of the cushion <NUM> or a nonwoven fabric and a configuration of a case-type that is formed by including a resin and a metal. Further, the cover <NUM> may have a configuration in which the entirety of the cushion <NUM> is covered. However, the cover <NUM> can maintain the cushion <NUM> when the cover <NUM> has a configuration in which only an area of the predetermined part is covered.

Because a predetermined fragile part is provided in the cover <NUM>, the cushion <NUM> can be released by fracturing the cover <NUM> when the cushion <NUM> is expanded and deployed. When the cover <NUM> is formed by such as the base cloth or the nonwoven fabric, the fragile part can be realized by such as a broken-line-shaped slit, a nick-shaped notch, an oblong hole-shaped slot, and in addition, a configuration in which ends of the cloths are crimped each other. Further, when the cover <NUM> is a container-shaped configuration that is formed by the resin molding, it can also be realized by providing a tear line that is reduced in thickness so as to induce the breakage.

<FIG> is a diagram that exemplarily shows the cushion <NUM> being in the stored state shown in Fig. 1B when viewed from each of directions. <FIG> exemplarily shows the seat <NUM> shown in Fig. 1B when viewed from the vehicle rear side. As exemplarily shown in <FIG>, the cushion <NUM> is stored by being divided into an inner side expansion part <NUM> at the occupant side and an outer side expansion part <NUM> at an opposite side of the occupant side with respect to the seat frame <NUM> so as to sandwich the seat frame <NUM>.

<FIG> is a cross-sectional view along the A - A line of such as the cushion <NUM> being in the stored state shown in <FIG>. As exemplarily shown in <FIG>, the inner side expansion part <NUM> is connected to the inflator <NUM> and receives the gas from the inflator <NUM> at the beginning within the cushion <NUM> so as to be expanded. The outer side expansion part <NUM> is continuously provided with the inner side expansion part <NUM> and receives the gas from the inner side expansion part <NUM> so as to be expanded and deployed. Because the cushion <NUM> being in the stored state is held at the seat frame <NUM> by being covered with the cover <NUM> explained above, the cushion <NUM> can be built in the seatback <NUM> in a state in which the inner side expansion part <NUM> and outer side expansion part <NUM> are formed.

The cushion <NUM> is folded back along a front edge <NUM> of the seat frame <NUM> between the inner side expansion part <NUM> and outer side expansion part <NUM> so that a first folded-back part <NUM> is provided. According to this configuration, it is possible that the cushion <NUM> is efficiently stored at the both sides that sandwich the seat frame <NUM> in the inside of the seatback <NUM>.

As explained above, in the present embodiment, because the cushion <NUM> is stored by being divided into at the occupant side and at the opposite side with respect to the seat frame <NUM>, the limited space of the inside of the seatback <NUM> in which such as a seat pad <NUM> is filled can be efficiently utilized. The side airbag device <NUM> can be applied to various vehicle seats that have a wide space or a narrow space with respect to a periphery of the seat frame <NUM> so as to have a high versatility. Further, because the installation space can be made narrow, the miniaturization of the vehicle seat can also be realized.

With respect to the side airbag device <NUM>, the front edge <NUM> of the seat frame <NUM> is bent so as to be rounded. As a result, with respect to the seat frame <NUM>, a thickness in the vehicle width direction of a region of the front edge <NUM> is larger to some extent than a thickness in the vehicle width direction of a region rearwardly located from the front edge <NUM>, for instance, such region corresponding to a region that extends in the front and rear direction of the seat and to which the stud bolt <NUM> of the inflator <NUM> is fasten. When the cushion <NUM> is stored by being divided into the inner side expansion part <NUM> and the outer side expansion part <NUM> and when the cushion <NUM> is expanded and deployed, this front edge <NUM> does not give a burden to the cushion <NUM>. Therefore, the cushion <NUM> can be efficiently stored in the seatback <NUM> and can operate without being damaged.

With respect to the side airbag device <NUM>, because the inner side expansion part <NUM> and the outer side expansion part <NUM> are separately stored, it is possible to not only be efficiently stored inside the seatback <NUM> that is narrow but also improve the acceleration of the expansion and deployment and the occupant restraint force. A further configuration according to the side airbag device <NUM> will be explained with reference to <FIG> below.

<FIG> is a diagram that exemplarily shows a process in which the cushion <NUM> shown in <FIG> is expanded and deployed. <FIG> exemplarily shows an overview of the cushion <NUM> being in the stored state shown in <FIG>. As exemplarily shown in <FIG>, substantial parts of the outer side expansion part <NUM> are wound so as to reduce (shrink) in size. As a result, the outer side expansion part <NUM> can be efficiently stored in the limited space of the inside of the seatback <NUM>.

<FIG> exemplarily shows a state immediately after the inflator <NUM> shown in <FIG> operated. As show in <FIG>, when the gas is supplied from the inflator <NUM>, the inner side expansion part <NUM> and the outer side expansion part <NUM> start to be expanded and deployed. By this force, the cover <NUM> is broken at the predetermined fragile part and releases the cushion <NUM>.

With respect to the cushion <NUM>, first of all, the inner side expansion part <NUM> that is stored at the occupant side of the seat frame <NUM> starts to be expanded. At this time, because the inner side expansion part <NUM> pushes a side surface <NUM> of the inner side of the seat frame <NUM> directly or indirectly through the cover <NUM>, the inner side expansion part <NUM> can receive a reaction force <NUM>. Because the inner side expansion part <NUM> is located at an upstream of the flow of the gas in the cushion <NUM>, the cushion <NUM> can receive the reaction force <NUM> directed from the seat frame <NUM> toward the occupant side by the inner side expansion part <NUM> at an early stage. Because of the reaction force <NUM> that the inner side expansion part <NUM> receives by the seat frame <NUM>, the cushion <NUM> can efficiently push aside, for instance, the seat pad <NUM> (refer to <FIG>) and the cover <NUM> so that the cushion <NUM> can be expanded and deployed more rapidly.

As exemplarily shown in <FIG>, in the present embodiment, the outer side expansion part <NUM> is stored in the seatback <NUM> in a state in which the outer side expansion part <NUM> directly comes in contact with the side surface <NUM> of the outer side of the seat frame <NUM> or in a state in which the outer side expansion part <NUM> indirectly comes in contact with the side surface <NUM> via the cover <NUM> that is another member. According to this configuration, as exemplarily shown in <FIG>, when the outer side expansion part <NUM> is expanded, the outer side expansion part <NUM> can efficiently receive a reaction force <NUM> by pushing the side surface <NUM> of the seat frame <NUM> directly or indirectly through the cover <NUM>. Even when the outer side expansion part <NUM> receives the reaction force <NUM> by the seat frame <NUM>, the cushion <NUM> can be expanded and deployed more rapidly.

<FIG> exemplarily shows a state in which the cushion <NUM> shown in <FIG> is further expanded and deployed. As explained above, the cushion <NUM> is rapidly expanded and deployed from the inside of the seatback <NUM> (refer to <FIG>) toward the side of the occupant by utilizing such as the reaction force <NUM> that the inner side expansion part <NUM> receives by the seat frame <NUM> (refer to <FIG>), the reaction force <NUM> that the outer side expansion part <NUM> receives by the seat frame <NUM>, and in addition, a force <NUM> for making the first folded-back part <NUM> to disappear that is located between the inner side expansion part <NUM> and the outer side expansion part <NUM>.

As explained above, because the cushion <NUM> is rapidly exposed from the seatback <NUM>, the cushion <NUM> can perform to push the occupant toward the direction away from the vehicle collision side at an early stage in a detection of an impact and a pre-detection of the impact, that is, the cushion <NUM> can perform a pre-push function. According to the pre-push function, because the occupant is push back to some extent before the entirety of the cushion <NUM> is expanded, the impact is reduced when the occupant is restrained by the entirety of the cushion <NUM> so that the injury value of the occupant can be suppressed.

The inner side expansion part <NUM> is provided at the occupant side of the seat frame <NUM>, and the inner side expansion part <NUM> is also the basis of the cushion <NUM>. Therefore, after the cushion <NUM> is expanded, the cushion <NUM> is also located at the occupant side of the seat frame <NUM>, that is, the cushion <NUM> is positioned closer to the occupant. According to this configuration, the occupant restraint force can also be improved.

<FIG> is a diagram that exemplarily shows first and second variations of the cushion <NUM> shown in <FIG>. <FIG> corresponds to <FIG> and exemplarily shows a cushion <NUM> according to the first variation. The cushion <NUM> is different from the cushion <NUM> shown in <FIG> with respect to a configuration relating to a reduction (shrinkage) method of an outer side expansion part <NUM>. In the following descriptions, with respect to the elements that are already explained, the explanations thereof are omitted by accompanying the same reference numerals. Further, when there are the elements that have different reference numerals and when these elements have the same names with the elements that are already explained, the basic configuration and functions of these elements are the same as the already explained elements.

As exemplarily shown in <FIG>, an outer side contact part <NUM> that comes in contact with a predetermined area of the side surface <NUM> extending from the front edge <NUM> toward the vehicle rear is formed at the outer side expansion part <NUM>. The outer side contact part <NUM> is in a state in which the outer side contact part <NUM> directly comes in contact with the side surface <NUM> or in a state in which the outer side contact part <NUM> indirectly comes in contact with the side surface <NUM> via the cover <NUM> that is another member.

A second folded-back part <NUM> is also formed at the outer side expansion part <NUM>. The second folded-back part <NUM> is formed by being folded back from a rear end at the vehicle rear side of the outer side contact part <NUM> toward the vehicle front.

<FIG> exemplarily shows a state immediately after the inflator <NUM> shown in <FIG> operated. When the gas is flown into the outer side expansion part <NUM>, the outer side contact part <NUM> is expanded first, and thereafter the second folded-back part <NUM> is expanded so as to make the folded-back to disappear. As a result, the rest of the outer side expansion part <NUM> can be expanded and deployed while the rest of the outer side expansion part <NUM> receives the reaction force <NUM> by more efficiently pushing the side surface <NUM> of the seat frame <NUM>. As explained above, the cushion <NUM> can be expanded and deployed more rapidly from the inside of the seatback <NUM> (refer to <FIG>) toward the side of the occupant by having the outer side contact part <NUM> and the second folded-back part <NUM> so that the occupant restraint force can be improved.

<FIG> corresponds to <FIG> and exemplarily shows a cushion <NUM> according to the second variation. The cushion <NUM> is also different from the cushion <NUM> shown in <FIG> with respect to a configuration relating to a reduction (shrinkage) method of an outer side expansion part <NUM>.

As exemplarily shown in <FIG>, with respect to the outer side expansion part <NUM>, an upstream region <NUM> extends from the front edge <NUM> of the seat frame <NUM> toward the vehicle rear and is located at the outermost position in the vehicle width direction of the outer side expansion part <NUM>. Further, a downstream region <NUM> that is wound is stored between the upstream region <NUM> and the seat frame <NUM>. The downstream region <NUM> is a region that is expanded by receiving the gas from the upstream region <NUM> and is stored in a state in which the downstream region <NUM> directly comes in contact with the side surface <NUM> of the seat frame <NUM> or in a state in which the downstream region <NUM> indirectly comes in contact with the side surface <NUM> via the cover <NUM>.

<FIG> exemplarily shows a state immediately after the inflator <NUM> shown in <FIG> operated. With respect to the outer side expansion part <NUM>, when the gas is flown from the upstream region <NUM> into the downstream region <NUM>, the downstream region <NUM> is expanded while the downstream region <NUM> pushes the side surface <NUM> of the seat frame <NUM> directly or indirectly through the cover <NUM>. As a result, the outer side expansion part <NUM> can also more efficiently push the side surface <NUM> of the seat frame <NUM> so as to receive the reaction force <NUM>. The cushion <NUM> can be expanded and deployed more rapidly from the inside of the seatback <NUM> (refer to <FIG>) toward the side of the occupant by the upstream region <NUM> and the downstream region <NUM> so that the occupant restraint force can be improved.

<FIG> is a diagram that exemplarily shows third and fourth variations of the cushion <NUM> shown in <FIG>. <FIG> corresponds to <FIG> and exemplarily shows a cushion <NUM> according to the third variation. The cushion <NUM> is also different from the cushion <NUM> shown in <FIG> with respect to a configuration relating to a reduction (shrinkage) method of an outer side expansion part <NUM>.

As exemplarily shown in <FIG>, with respect to the outer side expansion part <NUM>, substantial parts are folded in bellows so as to reduce (shrink) in size, and the outer side expansion part <NUM> are stored in a state in which the outer side expansion part <NUM> directly comes in contact with the side surface <NUM> of the seat frame <NUM> or in a state in which the outer side expansion part <NUM> indirectly comes in contact with the side surface <NUM> via the cover <NUM>. According to this configuration, in the same manner as the outer side expansion part <NUM> that is wound and shown in <FIG>, the outer side expansion part <NUM> can be efficiently stored in the limited space of the inside of the seatback <NUM> (refer to <FIG>).

<FIG> exemplarily shows a state immediately after the inflator <NUM> shown in <FIG> operated. With respect to the cushion <NUM>, because the outer side expansion part <NUM> is stored in the state in which the outer side expansion part <NUM> directly or indirectly comes in contact with the side surface <NUM> of the outside of the seat frame <NUM>, the outer side expansion part <NUM> can also efficiently receive the reaction force <NUM> by pushing the side surface <NUM> of the seat frame <NUM> directly or indirectly through the cover <NUM> when the outer side expansion part <NUM> is expanded. Because the outer side expansion part <NUM> receives the reaction force <NUM> by the seat frame <NUM>, the cushion <NUM> can be expanded and deployed more rapidly.

With respect to the cushion <NUM> shown in <FIG>, the outer side contact part <NUM> and the second folded-back part <NUM> shown in <FIG> can also be provided in combination with the configuration. By combining the second folded-back part <NUM> and so on, the outer side expansion part <NUM> that is folded in bellows can also efficiently receive the reaction force <NUM> by the seat frame <NUM>. Further, with respect to the cushion <NUM>, it is also possible that the upstream region <NUM> shown in <FIG> is provided and the part being folded in bellows is stored at a corresponding position of the downstream region <NUM>. According to this configuration, the outer side expansion part <NUM> can also efficiently receive the reaction force <NUM> by the seat frame <NUM>.

<FIG> is a diagram that exemplarily shows a fourth variation of the cushion <NUM> shown in <FIG>. <FIG> corresponds to <FIG> and exemplarily shows a cushion <NUM> according to the fourth variation. With respect to the cushion <NUM>, not only the outer side expansion part <NUM> are folded in bellows but also an inner side expansion part <NUM> are folded in bellows. Although the part being folded in bellows is included in the inner side expansion part <NUM>, the cushion <NUM> can be efficiently stored in the limited space of the inside of the seatback <NUM> (refer to <FIG>).

<FIG> exemplarily shows a state immediately after the inflator <NUM> shown in <FIG> operated. As exemplarily shown in <FIG>, the cushion <NUM> starts to be expanded from the inner side expansion part <NUM> that is stored at the occupant side of the seat frame <NUM>. At this time, the inner side expansion part <NUM> can be expanded while the inner side expansion part <NUM> makes the part being folded in bellows to be eliminated (disappear) and receives the reaction force <NUM> by pushing the side surface <NUM> of the inner side of the seat frame <NUM> directly or indirectly through the cover <NUM>. Because the inner side expansion part <NUM> is located at an upstream of the flow of the gas in the cushion <NUM>, the cushion <NUM> can receive the reaction force <NUM> directed from the seat frame <NUM> toward the occupant side by the inner side expansion part <NUM> at an early stage. Because the inner side expansion part <NUM> receives the reaction force <NUM> by the seat frame <NUM>, the cushion <NUM> can efficiently push aside, for instance, the seat pad <NUM> (refer to <FIG>) and the cover <NUM> so that the cushion <NUM> can be expanded and deployed more rapidly.

With respect to the cushion <NUM> shown in <FIG>, in the same manner as the cushion <NUM> shown in <FIG>, it is also possible that the outer side contact part <NUM> and the second folded-back part <NUM> shown in <FIG> are combined with the configuration or that the part being folded in bellows is stored at a corresponding position of the downstream region <NUM> by combining the upstream region <NUM> shown in <FIG>. Further, the inner side expansion part <NUM> can also be provided in combination with the outer side expansion part <NUM> shown in <FIG>, the outer side expansion part <NUM> shown in <FIG>, and the outer side expansion part <NUM> shown in <FIG>. Fifth Variation of Cushion.

<FIG> is a diagram that exemplarily shows a fifth variation of the cushion <NUM> shown in <FIG>. <FIG> corresponds to <FIG> and exemplarily shows a cushion <NUM> according to the fifth variation. With respect to the cushion <NUM>, not only the outer side expansion part <NUM> is stored by being wound but also an inner side expansion part <NUM> is stored by being wound. Although the inner side expansion part <NUM> includes the part (an inner folding part <NUM>) being reduced in size by winding and folding, the cushion <NUM> can be efficiently stored in the limited space of the inside of the seatback <NUM> (refer to <FIG>).

An inner side contact part <NUM> and a third folded-back part <NUM> are also provided at the inner side expansion part <NUM>. The inner side contact part <NUM> extends from a position of the seat frame <NUM> to which the inflator <NUM> is attached toward the front edge <NUM> of the seat frame <NUM> while the inner side contact part <NUM> directly comes in contact with the side surface <NUM> of the seat frame <NUM> or indirectly comes in contact with the side surface <NUM> via the cover <NUM> that is another member.

The third folded-back part <NUM> is formed by being folded back from the front edge at the vehicle front of the inner side contact part <NUM> toward the vehicle rear. The inner folding part <NUM> is provided at a distal position of the third folded-back part <NUM> and the base cloth of the inner side expansion part <NUM> extends from the third folded-back part <NUM> toward the front edge <NUM> again.

According to the configuration explained above, when the gas is flown into the inner side expansion part <NUM>, because the inner side contact part <NUM> is expanded first so that the third folded-back part <NUM> is expanded so as to eliminate the folded-back, the inner side contact part <NUM> pushes the side surface <NUM> of the seat frame <NUM> directly or indirectly through the cover <NUM>. As a result, it becomes possible that the reaction force <NUM> directed from the seat frame <NUM> toward the occupant side is efficiently received immediately after starting the inflow of the gas. Therefore, according to the configuration explained above, because the reaction force <NUM> directed toward the occupant side can be obtained at the initial stage of the expansion and deployment of the cushion <NUM>, the acceleration of the expansion and deployment and the further improvement of the occupant restraint force can be realized.

Further, in the same manner as the inner side expansion part <NUM> shown in <FIG>, the inner side expansion part <NUM> can also be provided in combination with any of the outer side expansion parts <NUM>, <NUM>, <NUM>, and <NUM> explained above. Further, the inner side contact part <NUM> and the third folded-back part <NUM> can be provided in combination with the inner side expansion part <NUM> that is folded in bellows shown in <FIG>. Variation of Seat Frame.

<FIG> is a diagram that exemplarily shows a variation of the seat frame <NUM> shown in <FIG>. A seat frame <NUM> is different from the seat frame <NUM> shown in <FIG> with respect to a configuration of a front edge <NUM>.

The front edge <NUM> of the seat frame <NUM> is thicker in the vehicle width direction. In addition, a chamfer <NUM> is provided so as to eliminate an acute angle. In other words, with respect to the seat frame <NUM>, a thickness in the vehicle width direction of a region of the front edge <NUM> in which the chamfer <NUM> is provided is larger to some extent than a thickness in the vehicle width direction of a region rearwardly located from the front edge <NUM>, for instance, such region corresponding to a region that extends in the front and rear direction of the seat and to which the stud bolt <NUM> of the inflator <NUM> is fasten. In the same manner as the front edge <NUM> (refer to <FIG>) that is rounded, when the cushion <NUM> is stored by being divided into the inner side expansion part <NUM> and the outer side expansion part <NUM> and when the cushion <NUM> is expanded and deployed, this front edge <NUM> also does not give a burden to the cushion <NUM>. Therefore, the cushion <NUM> can be efficiently stored in the seatback <NUM> (refer to <FIG>) and can operate without being damaged.

Although the preferred embodiments of the present invention have been described with reference to the attached drawings, the above-described embodiments are preferred examples of the present invention, and other embodiments can also be carried out in various ways. Unless there is a limited description in the specification, the present invention should not be limited to the detailed shape, size, configuration, and arrangement of parts shown in the attached drawings. Further, the expressions and terms used in the specification are for illustrative purposes, and unless there is a limited description, the same are not limited thereto.

Accordingly, it will be apparent to one of ordinary skill in the art to conceive various modifications within the scope of the claims. All such modifications are intended to be included within the technical scope of the present invention.

Claim 1:
A side airbag device (<NUM>) comprising:
a seat frame (<NUM>) that is along a side surface of a seatback of a vehicle seat, the seat frame (<NUM>) being built in the seatback (<NUM>);
an inflator (<NUM>) that is attached to an occupant side of the seat frame (<NUM>); and
an airbag cushion (<NUM>) that receives a gas from the inflator (<NUM>) so as to be expanded and deployed,
wherein the airbag cushion (<NUM>) includes:
an inner side expansion part (<NUM>) that is stored at the occupant side of the seat frame (<NUM>) by being wound, the inner side expansion (<NUM>) part being connected to the inflator (<NUM>); and
an outer side expansion part (<NUM>) that is continuously provided with the inner side expansion part (<NUM>), the outer side expansion part (<NUM>) is stored by being wound at an opposite side of the seat frame (<NUM>) with respect to the occupant side, the outer side expansion part (<NUM>) receiving the gas from the inner side expansion part (<NUM>) so as to be expanded and deployed;
wherein
the airbag cushion (<NUM>) has a first folded-back part (<NUM>) that is located between the inner side expansion part (<NUM>) and the outer side expansion part (<NUM>), and the airbag cushion (<NUM>) is folded back along a front edge of the seat frame (<NUM>) with respect to the first folded-back part (<NUM>)
characterized in that
the inner side expansion part (<NUM>) includes:
an inner contact part that directly comes in contact with the seat frame (<NUM>) or indirectly comes in contact with the seat frame (<NUM>) by sandwiching a cover (<NUM>) between the inner contact part and the seat frame (<NUM>) and extends from a position to which the inflator (<NUM>) is attached toward a front edge of the seat frame (<NUM>) ;
a third folded-back (<NUM>) part with which the inner side expansion part (<NUM>) is folded back from a front edge at a vehicle front side of the inner contact part toward a vehicle rear; and
an inner folding part (<NUM>) that further extends from the third folded-back part (<NUM>) toward the front edge.