Seat airbag device

Abstract

Provided is an airbag device capable of effectively suppressing a slide-down phenomenon. The present invention is an airbag device housed inside a vehicle seat having a seat cushion constituting a seat surface and a seat back that can be tilted, and has an airbag that has a structure to push a passenger's waist forward by expanding and deploying, and an angle sensor that detects a tilt angle of the seat back. When a vehicle is in an emergency, and the tilt angle of the seat back is greater than a prescribed value, the airbag is deployed.

Description

Technical Field

[0001] This invention relates to a safety airbag device built into a vehicle seat. Background Technology

[0002] As is well known, one or more airbags are installed in a vehicle to protect occupants in the event of an accident. Airbags come in various forms, such as driver's airbags, which inflate near the center of the steering wheel to protect the driver; curtain airbags, which deploy downwards from the inside of the windows to protect occupants in lateral impacts, rollovers, or rollover accidents; and side airbags, which deploy between the occupant and the side panel to protect occupants in the event of a lateral impact.

[0003] In the event of a frontal collision, occupants may move forward due to inertia, sometimes causing them to slip out of their seatbelts and slide into the legroom—a phenomenon known as "submarine." This is especially true if the seat is reclined. If submarine occurs, the seatbelt may become trapped in the occupant's abdomen or chest, and in the worst case, it may become trapped around the neck, causing pressure on that area.

[0004] Therefore, as shown in Patent Document 1, an invention is proposed that restrains the forward movement of the occupant's waist by inflating the airbag inside the seat and raising the front part of the seat cushion.

[0005] However, the invention described in Patent Document 1 cannot effectively prevent the downward sliding phenomenon.

[0006] Existing technical documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2007-118820 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] In view of the above circumstances, the present invention aims to provide an airbag device that can effectively suppress downward sliding.

[0010] Problem Solving Methods

[0011] To achieve the aforementioned objective, the present invention provides an airbag device housed within a vehicle seat having a seat cushion forming the seat surface and a tiltable backrest. The airbag has a structure that, upon expansion, pushes the occupant's lower back forward, and includes an angle sensor for detecting the tilt angle of the seat backrest. In the event of a vehicle emergency, and if the tilt angle of the seat backrest exceeds a predetermined value, the airbag deploys.

[0012] Here, the term "vehicle emergency" refers not only to the moment when a collision actually occurs, but also to the situation just before a collision is imminent and unavoidable, where the probability of a collision is high.

[0013] Preferably, by deploying the airbag, the occupant's pelvis is tilted upwards before the occupant slides forward.

[0014] In this invention, when a vehicle collision occurs with the backrest tilted at an angle greater than a specified value, the airbag deploys to push the occupant's waist forward, thereby raising the occupant's pelvis. At this time, the seatbelt located near the occupant's waist can reliably contact the pelvis, thus restraining the occupant. In existing vehicle seats, if a collision occurs at a large tilt angle, the occupant's buttocks may slide forward on the seat cushion, and the seatbelt supporting the lumbar region may rub against the pelvis and become lodged in the abdomen.

[0015] The airbag device can be housed in the lower part of the seat back. In this invention, it is important that the airbag is deployed at a sufficiently low position, thereby reliably pushing the occupant's waist forward and raising the occupant's pelvis.

[0016] The specified tilt angle can be a 15° rearward tilt relative to vertical while keeping the vehicle horizontal. Furthermore, this angle can be appropriately varied depending on the shape of the seat cushion or backrest, the coefficient of friction, etc.

[0017] The airbag can be constructed using a frame housed inside the seat back as the reaction surface for deployment. By using a rigid frame as the reaction surface, the airbag can reliably deploy forward.

[0018] When the airbag device is deployed, it can be configured such that the surface of the seat back cracks, exposing the airbag to the outside. Alternatively, it can be configured such that the airbag inflates only inside the seat back (as shown in the illustration).

[0019] The airbag can be configured to protrude and deploy at the boundary between the seat back and the seat cushion. Thus, by making the airbag protrude at the boundary between the backrest and the seat cushion, or as described above, by causing the airbag to deploy through a crack in the backrest's surface, the resistance of the polyurethane layer (cushioning layer) of the backrest and seat cushion can be minimized. That is, during airbag deployment, interference caused by the polyurethane layer of the backrest or seat cushion can be suppressed, thereby reliably deploying the airbag.

[0020] The airbag may include an upper region extending in a strip shape from the lower part of the seat back to the upper part.

[0021] By setting up such an upper area, not only can the occupant's waist be raised, but also the entire back can be raised, thus making the pelvic elevation effect more significant through the airbag.

[0022] The upper region of the airbag can be configured such that its thickness increases from top to bottom when deployed.

[0023] Other airbags can also be installed inside the seat cushion, which will lift the front part of the seat cushion upwards and deploy when the vehicle is in an emergency.

[0024] Because the invention restrains the occupant's forward movement by lifting the front portion of the seat cushion using other airbags, it makes the pelvic elevation effect more pronounced.

[0025] The airbag can be configured to inflate and deploy by expanding gas generated by an inflator.

[0026] The airbag can be configured to inflate and deploy using air generated by an air pump.

[0027] The air pump can be driven by an electric motor.

[0028] As described above, in the case of a structure where the airbag is inflated and deployed using an electric motor-driven air pump, since there is no gunpowder ignition like with an inflator, the airbag can be reused after deployment without needing to be replaced. In other words, it has the advantage of enabling reversible operation of the airbag system.

[0029] Furthermore, in the specification and claims of this application, when an occupant is seated in a proper posture, the direction the occupant is facing (the direction of vehicle travel) is referred to as "front," and the opposite direction is referred to as "rear," which is called "front-rear direction" when representing coordinate axes. Additionally, when an occupant is seated in a proper posture, the occupant's right side is referred to as "right direction," and the occupant's left side is referred to as "left direction," which is called "left-right direction" when representing coordinate axes. In the left-right direction, the area of ​​the seat's side frame closest to the occupant is called "inner," and the area opposite the occupant when viewed from the side frame is called "outer." Moreover, when an occupant is seated in a proper posture, the direction of the occupant's head is referred to as "above," and the direction of the occupant's waist is referred to as "below," which is called "up-down direction" when representing coordinate axes.

[0030] The airbag device involved in this invention is not limited to the driver's seat or the front passenger seat, but can also be applied to all seats with tilting function. Attached Figure Description

[0031] Figure 1This is a perspective view showing the external shape of a vehicle seat capable of accommodating the airbag device involved in this invention.

[0032] Figure 2 It is shown as Figure 1 The diagram shows a three-dimensional view of the internal structure (seat frame) in which the frame of the vehicle seat functions.

[0033] Figure 3 This is a schematic side view of a vehicle seat equipped with the airbag device according to the first embodiment of the present invention, showing a schematic view from the outside in the vehicle width direction.

[0034] Figure 4 This is a schematic side view of a vehicle seat equipped with the airbag device according to the first embodiment of the present invention, showing from... Figure 3 The condition causes the backrest to tilt significantly.

[0035] Figure 5 This is a schematic diagram showing the deployment of the airbag device according to the first embodiment of the present invention. (A) represents the state before deployment, (B) represents the first deployment mode (internal deployment), and (C) represents the second deployment mode (open deployment).

[0036] Figure 6 This is an explanatory diagram showing the restraint of the occupant's pelvis by the airbag device according to the first embodiment of the present invention, and showing the occupant's skeleton. (A) shows the state before deployment, and (B) shows the state after deployment.

[0037] Figure 7 This is an explanatory diagram showing the occupant's lumbar restraints without the airbag device involved in this invention (reference example), and also showing the occupant's skeleton.

[0038] Figure 8 This is a perspective view showing the structure of the airbag device according to the second embodiment of the present invention, showing its state mounted on the seat frame.

[0039] Figure 9 This is an explanatory diagram showing the restraint of the occupant's pelvis by the airbag device according to the second embodiment of the present invention, and showing the occupant's skeleton. (A) shows the state before deployment, and (B) shows the state after deployment.

[0040] Figure 10 This is an explanatory diagram showing the restraint of the occupant's pelvis by the airbag device according to the third embodiment of the present invention.

[0041] Figure 11 This is a schematic block diagram showing the structure of the airbag device according to the fourth embodiment of the present invention. Detailed Implementation

[0042] Hereinafter, the airbag device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0043] Figure 1 The main illustration shows an airbag device 20 (see reference) capable of carrying the airbag device involved in this invention. Figure 2 A three-dimensional drawing of the shape of the vehicle seat. Figure 2 It is shown as Figure 1 The diagram shows a three-dimensional view of the internal structure (seat frame) in which the frame of the vehicle seat functions. Figure 3 This is a schematic side view of a vehicle seat equipped with the airbag device 20 according to the present invention, showing a schematic view from the outside in the vehicle width direction.

[0044] like Figure 1 and Figure 2 As shown, the vehicle seat to which the airbag device 20 of this embodiment is applied, when viewed as a part, is configured to include a seat cushion 2 for the occupant to sit on, a backrest 1 forming a backrest, and a headrest 3 connected to the upper end of the backrest. The backrest 1 includes a back surface 1a that contacts the occupant's back and side support members 12.

[0045] like Figure 2 As shown, the backrest 1 has a backrest frame 1f forming the seat skeleton inside, and a pad (not shown) made of polyurethane foam or similar material is provided on its surface and around its perimeter. The surface of this pad is covered with leather, fabric, or other leather. The seat cushion 2 has a seating frame 2f on its underside, which, like the backrest 1, has a pad made of polyurethane foam or similar material on its upper surface and around its perimeter. The surface of this pad is covered with leather, fabric, or other leather. The seating frame 2f and the backrest frame 1f are connected by a tilting mechanism 4.

[0046] like Figure 2 The backrest frame 1f shown is a frame structure, consisting of side frames 10 arranged separately on the left and right and extending in the vertical direction, an upper frame connecting the upper end of the side frames 10, and a lower frame connecting the lower end. The headrest 3 is formed by providing a cushioning component on the outside of the headrest frame.

[0047] (First Embodiment)

[0048] Figure 3 This is a schematic side view of a vehicle seat equipped with the airbag device according to the first embodiment of the present invention, showing a schematic view from the outside in the vehicle width direction. Figure 4 It shows from Figure 3 The condition caused the backrest to tilt significantly.

[0049] The airbag device 20 involved in this embodiment is equipped with: an inflator 21 that generates expanding gas; an airbag 22 that expands and deploys using the expanding gas released from the inflator 21, thereby pushing the occupant's waist forward (or diagonally forward); and an angle sensor 4a that detects the tilt angle θ of the backrest 1. Furthermore, if a frontal collision of the vehicle occurs when the tilt angle of the backrest 1 is greater than a predetermined value, the airbag device 20 will activate and the airbag 22 will deploy.

[0050] The inflator 21 is housed inside the airbag 22 and fixed to the frame 1f disposed inside the backrest. The airbag 22 deploys with the rigid frame 1f as the reaction surface, thereby reliably deploying forward.

[0051] An angle sensor 4a, used to detect the tilt angle of the backrest 1, can be, for example, a potentiometer mounted on the tilt axis. When the tilt angle θ detected by the angle sensor 4a is greater than 15° when the vehicle is tilted backward relative to the vertical in a horizontal position, the airbag device 20 activates. Furthermore, this reference angle can be appropriately changed according to the shape of the seat cushion 2 or the backrest 1, the coefficient of friction, etc.

[0052] If the airbag 22 is deployed when the backrest 1 is not tilted, it may increase the pressure on the seat belt by pushing against the occupant's waist.

[0053] The airbag device 20 is preferably housed near the lower end of the backrest 1, thereby reliably pushing the occupant's waist forward and raising the occupant's pelvis before the occupant slides forward.

[0054] (Function of the first embodiment)

[0055] Figure 5 This is a schematic diagram showing the deployment of the airbag device 20. (A) indicates the state of the airbag 22 before deployment, (B) indicates the first deployment mode (internal deployment), and (C) indicates the second deployment mode (open deployment).

[0056] Figure 6 This is an explanatory diagram showing the restraint of the occupant's pelvis by the airbag device 20, and showing the occupant's skeleton. (A) shows the state before the airbag deploys, and (B) shows the state after the airbag deploys.

[0057] Figure 7 An explanatory diagram is provided to illustrate the occupant's lumbar restraints in the absence of the airbag device of the present invention (reference example), and the occupant's skeleton is shown.

[0058] like Figure 5 (A) Figure 6As shown in (A), it is assumed that a frontal collision occurs when the reclining angle θ of the backrest 1 is greater than a specified value (e.g., 15°). When a collision sensor (not shown) detects a frontal collision, as... Figure 5 (B) Figure 6 As shown in (B), the airbag 22 deploys, pushing the occupant's waist forward or diagonally forward. This allows the occupant's pelvis 30 to stand upright, and the seatbelt 32, located near the waist, reliably supports the pelvis. Additionally, in Figure 5 In the example shown in (B), the airbag 22 only deploys inside the backrest and does not protrude to the outside.

[0059] like Figure 7 As shown, in existing vehicle seats that do not have the airbag device 20 involved in this invention, if a vehicle collision occurs at a large tilt angle, the occupant's buttocks will slide forward on the seat cushion. As a result, the occupant may rub against the seat belt 32 due to the so-called downward sliding phenomenon, or the abdomen may be compressed by the seat belt 32 that supports the waist.

[0060] exist Figure 6 In the example shown in (C), due to the deployment of the airbag 22, the surface of the backrest 1 cracks, and the airbag 22 protrudes forward from near the boundary 5 between the backrest 1 and the seat cushion 2. By employing such a structure, the resistance of the polyurethane layer (buffer layer) of the backrest 1 or seat cushion 2 can be minimized. That is, when the device 20 is in operation, interference caused by the polyurethane layer (buffer layer) of the backrest 1 or seat cushion 2 can be suppressed, thereby reliably deploying the airbag 22.

[0061] (Second Embodiment)

[0062] Figure 8 This is a perspective view showing the structure of the airbag device according to the second embodiment of the present invention, showing its mounted on a frame. Figure 9 This is an explanatory diagram showing the pelvic restraint of the airbag device according to the second embodiment, and showing the occupant's skeleton. (A) shows the state before deployment, and (B) shows the state after deployment.

[0063] In the first embodiment, the airbag 22 only presses against the occupant's waist area, but in this embodiment, the airbag 122 is configured to press against the occupant's back in addition to pressing against the waist.

[0064] like Figure 8As shown, the airbag 122 used in this embodiment includes a lower region 122a disposed at a position on the lower part of the backrest 1 corresponding to the occupant's waist, and an upper region 122b extending upward in a strip shape from the lower region 122a along the backrest 1. The upper region 122b of the airbag 122 can be configured such that its thickness increases progressively and continuously towards the lower region 122a when deployed.

[0065] According to this embodiment, as Figure 9 As shown, by using an airbag 122 that extends in a strip along the vertical direction, not only can the occupant's waist be raised, but also the entire back can be raised, thus making the effect of raising the pelvis more significant.

[0066] (Third Embodiment)

[0067] Figure 10 This is an explanatory diagram showing the pelvic restraint of the airbag device according to the third embodiment of the present invention. In this embodiment, an airbag 220 is added to the first embodiment.

[0068] The airbag 220 may be made of fabric, metal or resin and housed inside the seat cushion 2. When the vehicle is involved in a collision, it deploys and lifts the front portion of the seat cushion 2 upward.

[0069] The airbag 220 can restrict the forward movement of the occupant by raising the front portion of the seat cushion 2. Moreover, by using the airbag 220 in conjunction with the airbag 20 used in the first embodiment, the effect of the present invention in raising the occupant's pelvis during a vehicle collision can be made more significant.

[0070] (Example 4)

[0071] Figure 11 This is a schematic block diagram showing the structure of the airbag device 320 according to the fourth embodiment of the present invention. In this embodiment, an air pump 330 and an electric motor 332 are used instead of the inflator 21 used in the first embodiment. That is, the airbag 322 is inflated and deployed by the air pump 330 and the electric motor 332.

[0072] In this embodiment, the air pump 330, driven by the electric motor 332, delivers instantaneously compressed air to the airbag 322, causing the airbag 322 to inflate and deploy. In the first embodiment, since there is no ignition of the inflator, after the airbag device 320 has been operated, it is not necessary to replace it with a new airbag device; the airbag 322, air pump 330, and electric motor 322 can be directly reused. That is, it has the advantage of enabling reversible operation of the airbag device 320.

[0073] Regarding the structure other than that which causes the airbag 322 to inflate and deploy, since it is the same as described in the first embodiment, repeated descriptions are omitted. Furthermore, this embodiment can also be applied to the second and third embodiments.

[0074] The present invention has been described above with reference to the embodiments, but the present invention is not limited to these embodiments, and appropriate modifications can be made within the scope of the technical concept of the present invention.

Claims

1. An airbag device housed in a vehicle seat having a seat cushion constituting a seat surface and a tiltable seat back, characterized by: an airbag having a structure that pushes a passenger's waist forward by expanding and deploying, and an angle sensor that detects an angle of inclination of the seat back, wherein the airbag is deployed when an emergency occurs in a vehicle and the angle of inclination of the seat back is greater than a prescribed value, the airbag further includes a lower region disposed at a position corresponding to the passenger's waist and an upper region extending in a band shape upward from the lower region along the seat back, and the upper region is configured so that a thickness thereof when deployed increases gradually and continuously toward the lower region.

2. The airbag device according to claim 1, characterized in that: a passenger's pelvis is erected before the passenger slides forward by deploying the airbag.

3. The airbag device according to claim 1, characterized in that: the airbag device is housed in a lower portion of the seat back.

4. The airbag device according to claim 1, characterized in that: the prescribed value of the angle of inclination is an angle of 15° backward with respect to vertical when the vehicle is in a horizontal state.

5. The airbag device according to claim 1, characterized in that: the airbag is deployed using a frame disposed inside the seat back as a reaction force surface.

6. The airbag device according to claim 1, characterized in that: the airbag device is configured so that a skin of the seat back is ruptured to expose the airbag to the outside when the airbag device operates.

7. The airbag device according to claim 1, characterized in that: the airbag device is configured so that the airbag inflates only inside the seat back when the airbag device operates.

8. The airbag device according to claim 1, characterized in that: the airbag is configured so that it protrudes and deploys at a boundary portion between the seat back and the seat cushion.

9. The airbag device according to any one of claims 1 to 8, characterized in that: another airbag is further provided, which is housed inside the seat cushion and deployed by lifting a front portion of the seat cushion upward when an emergency occurs in a vehicle.

10. The airbag device according to any one of claims 1 to 8, characterized in that: the airbag is configured to inflate and deploy by inflation gas generated by an inflator.

11. The airbag device according to any one of claims 1 to 8, characterized in that: the airbag is configured to inflate and deploy by air generated by an air pump.

12. The airbag device according to claim 11, characterized in that: the air pump is driven by an electric motor.

13. A vehicle provided with the airbag device according to any one of claims 1 to 8. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 13. A seat for a vehicle, characterized by ​

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