Cushion airbag device

Abstract

To provide a cushion airbag device capable of suppressing a reduction in ride comfort during normal vehicle travel, reducing the downward displacement of a passenger during a vehicle collision, and thereby preventing a decrease in waist restraining force by a lap belt of a seat belt.SOLUTION: A cushion airbag device 10 comprises: a cushion airbag 30 which is installed at a lower section of a seat cushion of a vehicle seat and expands in a vertical direction with gas supplied from a pressure storage tank 50; a control valve 54 which is installed in first piping 52 communicating the cushion airbag 30 with the pressure storage tank 50 and adjusts internal pressure of the cushion airbag 30; an exhaust valve 58 which is installed in the first piping 52 between the control valve 54 and the cushion airbag 30 and exhausts the gas from inside the cushion airbag 30; and a switch valve 64 which is installed in second piping 62 communicating the cushion airbag 30 with the pressure storage tank 50 and is opened during a vehicle collision.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a cushion airbag device.

Background Art

[0002] A vehicle seat in which a hip support area of a seat cushion pad is supported by an air cushion composed of two upper and lower air bags placed on a concave portion of a seat cushion frame has been conventionally known (for example, see Patent Document 1). In this vehicle seat, at the time of a vehicle collision, the air in the air bag is rapidly exhausted and the air cushion contracts, and the hip support area of the seat cushion pad instantaneously sinks, so that the occurrence of the submarine phenomenon is suppressed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the vehicle collides, if the air in the air bag is rapidly exhausted and the air cushion contracts, and the hip support area of the seat cushion pad instantaneously sinks, the waist of the occupant will instantaneously displace downward of the vehicle. Therefore, the relative displacement amount between the lap belt of the seat belt and the waist of the occupant increases, and there is a possibility that the waist restraint force by the lap belt decreases. Further, if the hip support area of the seat cushion pad is always supported by the air cushion, the hardness of the seat cushion increases, and the riding comfort (sitting comfort) performance may be impaired during normal running of the vehicle.

[0005] Therefore, the present invention aims to provide a cushion airbag device that can suppress a decrease in ride comfort performance during normal vehicle driving, reduce the amount of displacement of occupants toward the downward side of the vehicle during a vehicle collision, and suppress a decrease in the lumbar restraint force of the seat belt wrap belt. [Means for solving the problem]

[0006] To achieve the above objective, a cushion airbag device according to a first embodiment of the present invention comprises: a cushion airbag provided at the lower part of a seat cushion in a vehicle seat, which inflates vertically when gas is supplied from a pressure accumulator tank; a control valve provided in a first pipe connecting the cushion airbag and the pressure accumulator tank, which adjusts the internal pressure of the cushion airbag; an exhaust valve provided in the first pipe between the control valve and the cushion airbag, which exhausts the gas from inside the cushion airbag; and a switching valve provided in a second pipe connecting the cushion airbag and the pressure accumulator tank, which is opened in the event of a vehicle collision.

[0007] According to the first embodiment of the invention, a cushion airbag is provided at the bottom of the seat cushion in a vehicle seat. This cushion airbag inflates vertically when gas is supplied from a pressure accumulator tank. A control valve for adjusting the internal pressure of the cushion airbag is provided in a first pipe connecting the cushion airbag and the pressure accumulator tank, and an exhaust valve for exhausting gas from inside the cushion airbag is provided in the first pipe between the control valve and the cushion airbag. Therefore, during normal vehicle operation, the internal pressure of the cushion airbag can be adjusted (including a state where there is no gas), and a decrease in ride comfort performance is suppressed.

[0008] Furthermore, a switching valve is provided in the second pipe connecting the cushion airbag and the pressure accumulator, which is opened during a vehicle collision. In other words, during a vehicle collision, gas is instantly supplied from the pressure accumulator to the cushion airbag. Consequently, the amount of displacement of the occupant downwards during a vehicle collision is reduced, and the reduction in the lumbar restraint force of the seat belt's lap belt is suppressed. Note that "during a vehicle collision" in this invention includes not only when a vehicle collision is detected, but also when a vehicle collision is predicted. Also, "gas" in this invention includes air.

[0009] Furthermore, a cushion airbag device according to a second embodiment of the present invention comprises: a cushion airbag provided at the lower part of a seat cushion in a vehicle seat, which inflates vertically when gas is supplied from a pressure accumulator tank; a control valve provided in a pipe connecting the cushion airbag and the pressure accumulator tank, which adjusts the internal pressure of the cushion airbag; an exhaust valve provided in the pipe between the control valve and the cushion airbag, which exhausts the gas from inside the cushion airbag; and an inflator that operates during a vehicle collision and supplies gas to the inside of the cushion airbag.

[0010] According to the second embodiment of the invention, a cushion airbag is provided at the bottom of the seat cushion in a vehicle seat. This cushion airbag inflates vertically when gas is supplied from a pressure accumulator tank. A control valve for adjusting the internal pressure of the cushion airbag is provided in the piping connecting the cushion airbag and the pressure accumulator tank, and an exhaust valve for exhausting gas from inside the cushion airbag is provided in the piping between the control valve and the cushion airbag. Therefore, during normal vehicle operation, the internal pressure of the cushion airbag can be adjusted (including a state where there is no gas), and a decrease in ride comfort performance is suppressed.

[0011] Furthermore, an inflator that supplies gas to the inside of the cushion airbag activates during a vehicle collision. In other words, gas is instantly supplied from the inflator to the cushion airbag during a vehicle collision. Therefore, the amount of displacement of the occupant downwards during a vehicle collision is reduced, and the reduction in the lumbar restraint force of the seat belt's lap belt is suppressed. Note that "during a vehicle collision" in this invention includes not only when a vehicle collision is detected, but also when a vehicle collision is predicted. Also, "gas" in this invention includes air.

[0012] Furthermore, a third embodiment of the cushion airbag device according to the present invention is a cushion airbag device according to the first embodiment, wherein the switching valve is configured to include a bulkhead capable of closing the second piping and a stopper supporting the bulkhead, and is a mechanical valve in which the support of the bulkhead by the stopper is instantaneously released in the event of a vehicle collision.

[0013] According to the third embodiment of the invention, the switching valve is a mechanical valve comprising a bulkhead capable of closing the second piping and a stopper supporting the bulkhead, wherein the support of the bulkhead by the stopper is instantaneously released in the event of a vehicle collision. Therefore, compared to the case where the switching valve is a solenoid valve, gas is supplied to the cushion airbag more quickly, and lumbar restraint by the seat belt lap belt can be accelerated.

[0014] Furthermore, a fourth embodiment of the cushion airbag device according to the present invention is a cushion airbag device according to any one of the first to third embodiments, wherein when the vertical acceleration of the vehicle body exceeds a predetermined threshold while the vehicle is in motion, the control valve is opened for a predetermined time.

[0015] According to the fourth embodiment of the invention, when the vertical acceleration of the vehicle body exceeds a predetermined threshold while the vehicle is in motion, the control valve is opened for a predetermined time. In other words, the cushion airbag inflates at a low internal pressure. Therefore, the deterioration of ride comfort performance is effectively suppressed when the vehicle is driving on rough roads.

[0016] Furthermore, a fifth embodiment of the cushion airbag device according to the present invention is a cushion airbag device according to any one of the first to fourth embodiments, wherein the cushion airbag is constructed by sewing two base fabrics along their outer edges and folding them in half along a crease, thereby stacking them vertically, and has an air intake passage along the crease and an air intake port at one end of the crease, and is fixed to a mounting member installed between the side frames constituting the seat cushion with the crease positioned towards the front of the seat.

[0017] According to the fifth embodiment of the invention, the cushion airbag is constructed by sewing two base fabrics along their outer edges and folding them in half along creases, thereby stacking them vertically. This cushion airbag has an air intake passage along the creases and an air intake port at one end of the creases, and is fixed to a mounting member that is installed between the side frames constituting the seat cushion, with the creases positioned towards the front of the seat. Therefore, it is possible to significantly increase the thickness of the cushion airbag with a limited volume, and this large difference in thickness effectively reduces the amount of displacement of the occupant downwards during a vehicle collision, and effectively suppresses the reduction in the lumbar restraint force of the seat belt's wrap belt. [Effects of the Invention]

[0018] As described above, the present invention can suppress the deterioration of ride comfort performance during normal vehicle driving, reduce the amount of displacement of occupants downward during a vehicle collision, and suppress the reduction of lumbar restraint force by the seat belt wrap belt. [Brief explanation of the drawing]

[0019] [Figure 1] (A) A schematic side cross-sectional view showing the internal structure of a vehicle seat equipped with a cushion airbag according to this embodiment. (B) A schematic plan view showing a partially enlarged side view of the internal structure of a vehicle seat equipped with a cushion airbag according to this embodiment. [Figure 2](A) This is a schematic perspective view showing the cushion airbag according to this embodiment. (B) This is a schematic development view showing the cushion airbag according to this embodiment. [Figure 3] (A) This is a schematic configuration diagram showing the cushion airbag device according to this embodiment. (B) This is a schematic configuration diagram showing the cushion airbag device according to a modification of this embodiment. [Figure 4] (A) This is a schematic configuration diagram showing the switching valve before gas is supplied to the cushion airbag device according to this embodiment. (B) This is a schematic configuration diagram showing the switching valve after gas is supplied to the cushion airbag device according to this embodiment. [Figure 5] (A) This is a schematic side view showing the state before gas is supplied to the cushion airbag according to this embodiment. (B) This is a schematic side view showing the state after gas is supplied to the cushion airbag according to this embodiment. [Figure 6] This is a flowchart showing the operation process of the cushion airbag device according to this embodiment.

Embodiments for Carrying out the Invention

[0022] In addition, as shown in FIG. 1(B), this vehicle seat 12 has a seat frame 22 extending in the seat width direction in a plan view, and side frames 24 bent and extending rearward from both left and right end portions of the seat frame 22. The seat frame 22 and the side frames 24 are fixed to the floor 20 (see FIG. 1(A)) of the vehicle, and a seat pan 26 having a predetermined left-right symmetric shape is installed between the rear surfaces on both left and right sides of the seat frame 22 and the side surfaces on the inner side in the seat width direction of the side frames 24.

[0023] And between the left and right seat pans 2, a cylindrical submarine prevention reinforcement (hereinafter referred to as "submarine reinforcement 28") as a bridging member is installed. In this embodiment, the seat pan 26 is also regarded as a part of the side frame 24. Therefore, it can also be said that the submarine reinforcement 28 is installed between the left and right side frames 24.

[0024] A cushion airbag 30 is attached to this submarine reinforcement 28 by a fixing band 40 made of metal or resin, bolts 46, and nuts 48. Specifically described, as shown in FIGS. 2(A) and 2(B), the cushion airbag 30 is formed by sewing two silicon-coated base fabrics 32 along the outer peripheral edge and folding them in two along the fold line C so as to be stacked one above the other, and the tip portion 30A on the upper side is sewn to the lower side.

[0025] And this cushion airbag 30 has intake passages 34 having a substantially "L" shape in a plan view along the fold line C on both longitudinal sides of the fold line C. Further, this cushion airbag 30 has an intake port 36 for supplying gas toward each intake passage 34 at one longitudinal end portion of the fold line C. Therefore, the gas supplied from the intake port 36 is ejected through each intake passage 34 toward the central portions on the upper side and the lower side of the cushion airbag 30. Note that the "gas" in this embodiment includes air.

[0026] Furthermore, as shown in Figure 2(A), the cushion airbag 30 has multiple (for example, three) fixing tabs 38 sewn onto it at predetermined intervals along the fold line C. Each fixing tab 38 is formed in a roughly rectangular shape in plan view, for example, with a circular through hole 38A formed in its center. The cushion airbag 30 is positioned so that each fixing tab 38 (fold line C) is located towards the front, and each fixing tab 38 is sandwiched from above and below by the flange portion 44 of the fixing band 40 shown in Figure 1(B), which will be described later.

[0027] The fixing band 40 has a ring portion 42 that is roughly "C" shaped in side view and fitted to the submarine reinforcement 28, and a pair of flange portions 44 that are roughly rectangular in plan view and extend radially outward from the end of the ring portion 42, with a circular through hole (not shown) formed in the center of each flange portion 44.

[0028] Therefore, each fixing tab 38 is sandwiched from above and below by a pair of flange portions 44 of the fixing band 40, and bolts 46 are inserted into mutually communicating through holes (not shown) and through hole 38A (see Figure 2(A)), and nuts 48 are screwed onto the shafts of the bolts 46, thereby fixing them to the submarine reinforcement 28. In this way, the cushion airbag 30 is attached to the submarine reinforcement 28.

[0029] The cushion airbag 30, to which each fixing tab 38 is attached to the submarine reinforcement 28, is positioned between the base member 16 and the cushion pad 18 that constitute the seat cushion 14, as shown in Figures 1(A) and 5. During normal vehicle operation, it is not filled with gas. When gas is supplied to the cushion airbag 30, it inflates vertically, causing a portion of the cushion pad 18 (the front part of the occupant P's buttocks) to rise, as shown in Figure 5(B).

[0030] As shown in Figure 3(A), the vehicle (or vehicle seat 12) is equipped with a high-pressure tank 50, which serves as a pressure storage tank and is pressurized by a compressor 60. The high-pressure tank 50 and the cushion airbag 30 are connected by a first pipe 52. The first pipe 52 is equipped with a control valve (solenoid valve) 54 that adjusts the internal pressure of the cushion airbag 30. When the control valve 54 is opened, gas is supplied from the high-pressure tank 50 to the inside of the cushion airbag 30, causing the cushion airbag 30 to inflate vertically.

[0031] Furthermore, a branch pipe 56 is integrally provided in the first piping 52 between the control valve 54 and the cushion airbag 30, and an exhaust valve 58 for exhausting gas from inside the cushion airbag 30 is provided in the branch pipe 56. In addition, the high-pressure tank 50 and the cushion airbag 30 are connected by a second piping 62, and the inner diameter of the second piping 62 is formed to be larger than the inner diameter of the first piping 52. A switching valve 64 that opens in the event of a vehicle collision is provided in the second piping 62.

[0032] In this embodiment, "at the time of vehicle collision" includes not only when a vehicle collision is detected, but also when a vehicle collision is predicted. Furthermore, "at the time of emergency braking of a vehicle," as described later, includes not only when emergency braking of a vehicle is detected, but also when emergency braking of a vehicle is predicted. In addition, the control valve 54, exhaust valve 58, and switching valve 64 are each electrically connected to the control unit (ECU) 70, and their opening and closing are controlled by the control unit 70.

[0033] Here, the switching valve 64 is a mechanical valve that includes, for example, as shown in Figure 4(A), a partition wall 66 of a predetermined thickness that is sized to close the passage inside the second piping 62, and a stopper 68 of a predetermined size (having an area larger than the area of ​​the opening 62A described later) that supports the partition wall 66 from the downstream side in the direction of gas outflow (hereinafter simply referred to as the "downstream side") so that it does not tip over due to the high-pressure gas flowing out from the high-pressure tank 50.

[0034] The bulkhead 66 is supported so as to be rotatable about a pivot axis 67 whose axis is perpendicular to the direction in which the second pipe 62 extends in a plan view. One end of a tension coil spring 78, which serves as a biasing member for returning to its original position, is attached to the wall surface 66A on the upstream side (hereinafter simply referred to as the "upstream side") of the bulkhead 66 on the gas outflow direction. The other end of the tension coil spring 78 is attached to the upper inner wall of the second pipe 62 upstream of the bulkhead 66.

[0035] The stopper 68 is slidably mounted on the upper inner wall of the second pipe 62 downstream of the partition wall 66, along the extending direction of the second pipe 62. A hollow case 72 is integrally provided on the upper part of the second pipe 62 downstream of the partition wall 66. One end (upper end) of a compression coil spring 74, which serves as a biasing member for protrusion, is attached to the inner surface of the upper wall 72U of the case 72, and the other end (lower end) of the compression coil spring 74 is attached to the upper end surface of a substantially flat regulating member 76.

[0036] In other words, the restricting member 76 is biased downward by the compression coil spring 74 and protrudes downward from the opening 72A formed in the lower wall 72D of the case 72 and the opening 62A formed in the upper part of the second pipe 62. The downstream end face 68B of the stopper 68 abuts against the upstream wall face 76A at the lower end of the restricting member 76 that protrudes from the opening 72A in the lower wall 72D and the opening 62A in the second pipe 62.

[0037] Furthermore, the downstream wall surface 76B at the lower end of the restricting member 76 abuts against or is close to the upstream end surface 69A of the limiting member 69 fixed to the upper inner wall of the second pipe 62. As shown in Figure 4(B), this limiting member 69 is designed to restrict the stopper 68 from sliding downstream more than necessary.

[0038] In this state, the upstream end face 68A of the stopper 68 is in contact with the downstream wall surface 66B at the upper end of the partition wall 66. This configuration ensures that the partition wall 66 is supported by the stopper 68 so that it does not collapse downstream due to the high-pressure gas flowing out of the high-pressure tank 50.

[0039] Furthermore, a flange portion 77 is integrally formed on the upper part of the regulating member 76, and the outer peripheral end surface of the flange portion 77 abuts against the inner surface of the side wall 72S of the case 72. Explosives K are filled between the flange portion 77 of the regulating member 76 and the lower wall 72D of the case 72, and the case 72 is provided with an ignition device (not shown) for igniting the explosives K. This ignition device is electrically connected to a control device 70 (see Figure 3(A)).

[0040] Therefore, in the event of a vehicle collision, as shown in Figure 4(B), the ignition device is controlled by the control device 70 and the gunpowder K is ignited, causing the restricting member 76 to instantly rise inside the case 72 via the flange portion 77, and the upstream wall surface 76A of the lower end of the restricting member 76, which protrudes from the opening 72A of the lower wall 72D and the opening 62A of the second pipe 62, to instantly detach from the downstream end surface 68B of the stopper 68.

[0041] As a result, the support of the bulkhead 66 by the stopper 68 is instantaneously released, causing the bulkhead 66 to be pushed from the upstream side by the high-pressure gas and to tip over, and the high-pressure gas is instantly supplied to the inside of the cushion airbag 30. When the bulkhead 66 tips over, the stopper 68 is also pushed by the bulkhead 66 and slides downstream. In other words, the opening 62A of the second pipe 62 is closed by the stopper 68. Therefore, the high-pressure gas does not leak from the second pipe 62.

[0042] Furthermore, once all the high-pressure gas has been supplied to the inside of the cushion airbag 30, the bulkhead 66 returns to its original state due to the biasing force of the tension coil spring 78. That is, as shown in Figure 4(A), it closes the second pipe 62. In this way, the switching valve 64 can be reused by refilling the case 72 with explosive K.

[0043] The operation of the cushion airbag device 10 according to this embodiment, which has the configuration described above, will now be explained.

[0044] As described above, the cushion airbag 30 is positioned between the base member 16 and the cushion pad 18 that make up the seat cushion 14. As shown in Figure 5(A), the cushion airbag 30 is in a state where it is empty (exhausted) during normal vehicle operation. In other words, as shown in Figure 6, the control valve 54 and the exhaust valve 58 are closed (step S1), and the occupant P seated on the seat cushion 14 is supported by the base member 16 and the cushion pad 18.

[0045] Therefore, during normal vehicle operation, it is possible to avoid the seat cushion 14 becoming excessively hard due to the cushion airbag 30, and thus avoid any impairment of the ride comfort (seating comfort) performance of the seat cushion 14 for the occupant P. In other words, during normal vehicle operation, the internal pressure of the cushion airbag 30 can be adjusted (including a state where no gas is present), thereby suppressing or preventing a decrease in ride comfort (seating comfort) performance.

[0046] Next, in this state, in step S2, it is determined whether the vehicle's longitudinal acceleration (G) is greater than or equal to a predetermined first threshold. If a frontal collision of the vehicle is detected (or predicted) as being greater than or equal to the first threshold, the switching valve 64 is instantaneously opened (step S3), as shown in Figure 4(B). As a result, gas is instantly supplied from the high-pressure tank 50 into the cushion airbag 30, as shown in Figure 5(B), and the cushion airbag 30 inflates vertically.

[0047] In other words, a portion of the cushion pad 18 that makes up the seat cushion 14 (the front part of the occupant P's buttocks) rises. Therefore, the amount of downward displacement of the occupant P during a vehicle collision can be reduced, and the reduction in the lumbar restraint force by the lap belt 13A of the seat belt 13 can be suppressed.

[0048] On the other hand, in step S2, if it is determined that the longitudinal acceleration (G) of the vehicle is less than a predetermined first threshold, in step S4, it is determined whether the longitudinal acceleration (G) of the vehicle is greater than or equal to a predetermined second threshold which is less than the first threshold. If emergency braking that exceeds the second threshold is detected (or predicted), the control valve 54 is opened (step S5). The control valve 54 is open for a relatively long time at this time, and a relatively large amount of gas is supplied from the high-pressure tank 50 to the inside of the cushion airbag 30. In other words, the internal pressure of the cushion airbag 30 becomes high.

[0049] Therefore, the amount of downward displacement of the occupant P during emergency braking of the vehicle can be reduced, and the reduction in the lumbar restraint force by the lap belt 13A of the seat belt 13 can be suppressed. When the emergency braking of the vehicle is completed, the exhaust valve 58 is opened and gas is exhausted from inside the cushion airbag 30 (step S6). Then, in step S4 again, it is determined whether or not the longitudinal acceleration (G) of the vehicle is above a predetermined second threshold.

[0050] On the other hand, in step S4, if it is determined that the vehicle's longitudinal acceleration (G) is less than a predetermined second threshold, in step S7, it is determined by an onboard camera (not shown) or the like whether there are any irregularities on the road surface greater than a predetermined threshold. If there are no irregularities, the process returns to step S1. If there are irregularities, in step S8, it is determined whether the vehicle's vertical acceleration (G) is greater than or equal to a predetermined threshold. If it is determined to be greater than or equal to the threshold, the control valve 54 is opened for a predetermined time (step S9).

[0051] In other words, the opening time of the control valve 54 at this time is shorter than the opening time in step S5, and the amount of gas supplied from the high-pressure tank 50 to the inside of the cushion airbag 30 is small. As a result, the internal pressure of the cushion airbag 30 becomes low, and the cushion airbag 30 becomes a soft (low-hardness) cushion airbag.

[0052] Therefore, when a vehicle travels on a rough road with unevenness exceeding a predetermined level, the internal pressure of the cushion airbag 30 is set to a high pressure, which effectively suppresses the deterioration of ride comfort compared to the case where the cushion airbag is made of high hardness. In step S8, if the vertical acceleration (G) of the vehicle is less than a predetermined threshold, the exhaust valve 58 is opened (step S10), and the process returns to step S1.

[0053] Thus, the cushion airbag device 10 according to this embodiment can suppress a decrease in the ride comfort performance of the occupant P during normal vehicle driving, reduce the amount of downward displacement of the occupant P during a vehicle collision, and suppress a decrease in the lumbar restraint force by the lap belt 13A of the seat belt 13. In other words, this embodiment makes it possible to achieve both ensuring ride comfort performance during normal vehicle driving and suppressing or preventing the occurrence of the submarine phenomenon during a vehicle collision.

[0054] Furthermore, this cushion airbag 30 is constructed by sewing two base fabrics 32 along their outer edges and folding them in half along the fold line C, thereby stacking them vertically. This cushion airbag 30 has an air intake passage 34 along the fold line C and an air intake port 36 at one end of the fold line C, and is fixed to the submarine reinforcement 28 with the fold line C positioned towards the front.

[0055] Therefore, the cushion airbag 30, which has a limited volume, can have a significantly increased thickness, and this large difference in thickness can effectively reduce the amount of downward displacement of the occupant P during a vehicle collision or emergency braking, and can effectively suppress the reduction in the lumbar restraint force of the seat belt 13A.

[0056] Furthermore, the switching valve 64 is configured to include a bulkhead 66 capable of closing the passage of the second piping 62, and a stopper 68 that supports the bulkhead 66, and is a mechanical valve in which the support of the bulkhead 66 by the stopper 68 is instantaneously released in the event of a vehicle collision. Therefore, compared to the case where the switching valve 64 is, for example, a solenoid valve, the supply of gas to the cushion airbag 30 is performed more quickly, and the lumbar restraint by the lap belt 13A of the seat belt 13 can be accelerated.

[0057] The operation of the cushion airbag device 10 according to this embodiment is as described above, but the cushion airbag device 10 may also have the configuration shown in Figure 3(B). That is, the second piping 62 may be eliminated, and the inflator 80 may be mechanically connected to the cushion airbag 30, and the inflator 80 and the control device 70 may be electrically connected.

[0058] According to this, in the event of a vehicle collision, the control device 70 can instantly supply gas from the inflator 80 to the inside of the cushion airbag 30. Therefore, similar to the above, the amount of downward displacement of the occupant P during a vehicle collision can be reduced, and the reduction in the lumbar restraint force by the lap belt 13A of the seat belt 13 can be suppressed. In other words, the occurrence of the submarining phenomenon can be suppressed or prevented.

[0059] In this case, step S3 in the flowchart shown in Figure 6 is "inflator operation" instead of "switching valve opening". Also, in this case, there is only one pipe connecting the high-pressure tank 50 and the cushion airbag 30, so it is referred to as "pipe 52" instead of "first pipe 52". In other words, in this case, a control valve 54 is provided in pipe 52, and a branch pipe 56 is integrally provided in pipe 52 between the control valve 54 and the cushion airbag 30.

[0060] The cushion airbag device 10 according to this embodiment has been described above based on the drawings. However, the cushion airbag device 10 according to this embodiment is not limited to the illustrated version, and can be modified as appropriate without departing from the spirit of the present invention. For example, the position of the fold line C when the cushion airbag 30 is folded in half can be changed to match the structure of the seat cushion 14 of the vehicle seat 12 (shape and inclination of the base member 16 and cushion pad 18).

[0061] Furthermore, the vehicle seat 12 in this embodiment may be a captain's seat in the front, in which case the cushion airbag 30 is positioned between the seat spring (not shown) and the cushion pad 18. Also, the cushion airbag 30 is not limited to being attached to the submarine reinforcement 28, but may also be attached to a cross member (not shown) extending in the seat width direction of the vehicle seat 12. In addition, an exhaust valve 58 may be used together with the control valve 54 to adjust the internal pressure of the cushion airbag 30. [Explanation of Symbols]

[0062] 10. Cushion airbag system 12 Vehicle seats 14 Seat Cushions 16 Base member 18 Cushion pads 24 Side Frames 28. Submarine reinforcement (erecting component) 30 Cushion Airbags 32 Base fabric 34 Intake passage 36 Air intake 50 High-pressure tank (pressure storage tank) 52. First piping (piping) 54 Control valve 58 Exhaust valve 62. Second Piping 64 Switching valve 80 Inflator C fold line

Claims

1. A cushion airbag is provided at the bottom of the seat cushion in a vehicle seat and inflates vertically when gas is supplied from a pressure tank. A control valve is provided in the first piping that connects the cushion airbag and the pressure accumulator tank, and adjusts the internal pressure of the cushion airbag. An exhaust valve is provided in the first piping between the control valve and the cushion airbag, which exhausts the gas from inside the cushion airbag, A switching valve is provided in the second piping that connects the cushion airbag and the pressure accumulator, and is opened in the event of a vehicle collision. A cushion airbag device equipped with an airbag.

2. A cushion airbag is provided at the bottom of the seat cushion in a vehicle seat and inflates vertically when gas is supplied from a pressure tank. A control valve is provided in the piping that connects the cushion airbag and the pressure accumulator, and adjusts the internal pressure of the cushion airbag. An exhaust valve is provided in the piping between the control valve and the cushion airbag, and exhausts the gas from inside the cushion airbag, An inflator that activates during a vehicle collision and supplies gas to the inside of the cushion airbag, A cushion airbag device equipped with an airbag.

3. The aforementioned switching valve is It comprises a partition wall capable of closing the aforementioned second pipe, and a stopper that supports the partition wall, The cushion airbag device according to claim 1, wherein the stopper is a mechanical valve that instantaneously releases the support against the bulkhead by the stopper in the event of a vehicle collision.

4. The cushion airbag device according to claim 1 or claim 2, wherein when the vertical acceleration of the vehicle body exceeds a predetermined threshold while the vehicle is in motion, the control valve is opened for a predetermined time.

5. The aforementioned cushion airbag, Two base fabrics are sewn along their outer edges and folded in half along the creases, creating a structure where they are layered on top of each other. It has an intake passage along the aforementioned fold and an intake port at one end of the aforementioned fold, The cushion airbag device according to claim 1 or claim 2, wherein the aforementioned fold line is located on the front side of the seat and is fixed to a mounting member installed between the side frames constituting the seat cushion.

Images