Occupant posture regulation device

Abstract

To provide a technique that reduces a burden on an occupant at impact occurrence time.SOLUTION: An occupant posture regulation device for regulating the posture of an occupant seated on a seat 90 at vehicle impact occurrence time, comprises a lifting element 1 which actuates at the impact occurrence time. The lifting element 1 lifts a seating face 93 of the seat 90 upward so that at the impact occurrence time, a distance H in a vertical direction between a lumber part point Sw and a breast part point Sc in a THOR50M dummy 99 seated on the seat 90 becomes smaller compared to that in a normal time.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an occupant posture restraint device that is mounted on a vehicle and that restrains the posture of an occupant when an impact occurs. [Background technology]

[0002] BACKGROUND ART It is known that when an impact occurs in a vehicle, such as during a collision, a phenomenon occurs in which an occupant seated in a vehicle seat moves forward or downward despite wearing a seat belt. In this specification, the terms "front" and "forward" refer to the front and rear of the seat in the longitudinal direction relative to the body of the occupant seated on the seat. Similarly, the terms "rear" and "rearward" refer to the rear and rear of the seat in the longitudinal direction relative to the body of the occupant seated on the seat. In this specification, the width direction, which will be described later, refers to the horizontal direction and the direction perpendicular to the longitudinal direction. Furthermore, "up" and "down" refer to the vertical direction and the vertical direction, respectively.

[0003] One known example of the above phenomenon is the phenomenon in which an occupant slides downwards and forwards from the seat surface (the so-called submarine phenomenon). The submarining phenomenon is thought to occur when a vehicle is hit from the front, causing the occupant's waist to move forward and slip under the lap strap (also called a waist belt or lap strap) that is part of the seat belt and is designed to restrain the occupant's waist.

[0004] In order to prevent these occupants from moving, a technology has been proposed in which an airbag known as a seat cushion airbag is provided below the seat surface of the seat, more specifically, inside the seat portion (see, for example, Patent Document 1).

[0005] According to the technology introduced in Patent Document 1, a seat cushion airbag is deployed and inflated when an impact occurs, raising the seat surface. Paragraph

[0007] of Patent Document 1 explains that the seat cushion airbag lifts the thighs of the occupant, thereby preventing the occupant from moving forward. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-133079 Summary of the Invention [Problem to be solved by the invention]

[0007] However, even if a conventional seat cushion airbag such as that described in Patent Document 1 is activated, the occupant moves forward when an impact occurs. If the impact is large, the occupant moves forward significantly. In this case, the occupant's chest is pushed relatively strongly rearward by the seat belt, which may place a heavy burden on the occupant.

[0008] The inventors of the present invention have conducted extensive research to prevent the above-mentioned problem of the occupant's chest being pushed hard when an impact occurs, and as a result have found that the problem of the occupant's chest being pushed hard when an impact occurs is related to the occupant's posture at the time of the impact.

[0009] When an impact occurs, the occupant's waist is restrained by the waist strap of the seat belt, and the shoulders are restrained by the shoulder strap of the seat belt. If a conventional seat cushion airbag is deployed at this time, the occupant's thighs are lifted up, which is thought to suppress the submarine phenomenon and the like.

[0010] However, even when the occupant is restrained by the seat belt and the seat cushion airbag is deployed, a large forward force acts on the occupant. Because the occupant's waist is secured by the waist straps to prevent forward movement, if the impact is strong, the occupant's upper body will fall forward significantly. At this time, the shoulder straps are positioned along the occupant's chest, i.e., the area between the shoulders and waist, and the tension of the shoulder straps presses strongly against the occupant's chest.

[0011] The inventor of the present invention believed that when the shoulder straps are positioned along the occupant's chest in this way, the occupant's chest would be pressed hard against the seat, and aimed to regulate the occupant's posture so that the shoulder straps would not be positioned along the occupant's chest, thereby completing the present invention.

[0012] The present invention has been made in consideration of the above circumstances, and an object to be achieved is to provide a technique for reducing the burden on an occupant when an impact occurs. [Means for solving the problem]

[0013] The occupant posture restriction device of the present invention, which solves the above problems, is An occupant posture restriction device for restricting the posture of an occupant seated in a seat when a vehicle impact occurs, a lifting element that is activated upon the occurrence of the impact; The lifting element is an occupant posture control device that lifts the seat surface of the seat upward so that, when the impact occurs, the vertical distance between the waist point and chest point of a THOR50M dummy seated in the seat becomes smaller than normal.

[0014] The occupant posture restraining device of the present invention can reduce the burden on the occupant when an impact occurs. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is an explanatory diagram illustrating a passenger attitude restriction device according to a first embodiment, as viewed from above; [Figure 2] 1 is an explanatory diagram illustrating a schematic side view of an occupant posture restriction device according to a first embodiment. FIG. [Figure 3] 1 is an explanatory diagram illustrating a schematic side view of an occupant posture restriction device according to a first embodiment. FIG. [Figure 4] 1 is a diagram schematically illustrating an airbag in an occupant posture restraint device according to a first embodiment, as viewed from above. [Figure 5] 2 is a diagram showing a schematic side view of an airbag in the occupant posture restraint device of the first embodiment. FIG. [Figure 6] 2 is a diagram illustrating a schematic view of an airbag in the occupant posture restriction device of the first embodiment, viewed from the side and rear. FIG. [Figure 7] FIG. 10 is an explanatory diagram illustrating a passenger attitude restriction device according to a second embodiment, as viewed from the side. [Figure 8] FIG. 10 is an explanatory diagram illustrating a passenger attitude restriction device according to a third embodiment, as viewed from the side. [Figure 9] FIG. 10 is an explanatory diagram for schematically explaining an occupant attitude restriction device according to a fourth embodiment. [Figure 10] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 11] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 12] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 13] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 14] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 15] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 16] 1 is an explanatory diagram illustrating an embodiment of an airbag in an occupant posture restraint device according to the present invention; [Figure 17] FIG. 1 is an explanatory diagram illustrating a conventional seat and a dummy seated in the seat, as viewed from the side. DETAILED DESCRIPTION OF THE INVENTION

[0016] As mentioned above, the inventor of the present invention considered that the problem of the occupant's chest being pressed hard by the shoulder straps of the seat belt when an impact occurs is related to the occupant's posture when the impact occurs.

[0017] The following description will be given by replacing the occupant seated in the seat with a dummy seated in the seat. For example, as shown in FIG. 2, a shoulder strap 94s of a seat belt 94 is hung from a shoulder 99s of a dummy 99 seated in a seat 90, along a chest 99c, to a waist 99w.

[0018] For example, when a conventional seat cushion airbag device 101 shown in Fig. 17 is activated upon impact, the thighs of the dummy 99 are lifted, but the upper body of the dummy 99 falls forward, causing the shoulder straps 194s of the seat belt 194 to tightly restrain the chest 99c of the dummy 99. As a result, the chest 99c of the dummy 99 is pressed firmly by the shoulder straps 194s.

[0019] The inventor took this idea a step further and came to the realization that if the shoulder straps are not aligned with the occupant's chest when an impact occurs, the occupant's chest can be prevented from being pressed hard by the shoulder straps.

[0020] The occupant posture restriction device of the present invention restricts the posture of an occupant seated in a seat when a vehicle impact occurs, thereby preventing the shoulder straps from being positioned along the occupant's chest when an impact occurs.

[0021] The occupant posture restraint device of the present invention includes a lifting element that is activated when a vehicle impact occurs. The lifting element lifts the seat surface of the seat upward so that the shoulder straps are not aligned with the occupant's chest upon impact. More specifically, the lifting element lifts the seat surface of the seat upward so that the vertical distance between the lumbar point and the thoracic point of a THOR50M dummy seated in the seat becomes smaller than normal.

[0022] The THOR50M dummy is a type of dummy used for crash safety performance tests.

[0023] The THOR50M dummy has a portion corresponding to the occupant's waist and a portion corresponding to the occupant's chest. In this specification, a predetermined point on the THOR50M dummy's portion corresponding to the occupant's waist is referred to as the waist point, and a predetermined point on the THOR50M dummy's portion corresponding to the occupant's chest is referred to as the chest point.

[0024] The THOR50M dummy has a lumbar acceleration sensor in the area corresponding to the occupant's waist, and a thoracic acceleration sensor in the area corresponding to the occupant's chest, more specifically, at a point on the THOR50M dummy corresponding to the human body, i.e., the occupant's fourth thoracic vertebra. Therefore, the lumbar point can be read as the lumbar acceleration sensor, and the chest point can be read as the thoracic acceleration sensor. During a vehicle collision, the THOR50M dummy seated in the vehicle's seat behaves in the same way as a passenger seated in that seat.

[0025] When the THOR50M dummy is seated in a vehicle seat, if the vertical distance between the waist point and chest point of the THOR50M dummy becomes smaller than normal, the vertical distance between the waist and chest of the occupant seated in the seat becomes closer than normal. In other words, in this situation, the occupant's back will be bent forward, resulting in a hunched posture.

[0026] If the occupant is hunched over, the shoulder straps will not be aligned with the occupant's chest but will be stretched between the occupant's shoulders and waist. This creates a gap between the shoulder straps and the occupant's chest, which is located between the shoulders and waist. This prevents or reduces the tension of the shoulder straps from pushing the occupant's chest too hard. In other words, the occupant posture restraint device of the present invention can reduce the strain on the occupant during an impact.

[0027] Hereinafter, as necessary, the THOR50M dummy will be referred to simply as the dummy, and the vertical distance between the lumbar point and the chest point will be referred to as the vertical point distance. Furthermore, when the vertical point distance of a dummy seated in a seat becomes smaller than normal, this will be referred to as the dummy hunching over in the seat. Furthermore, the parts of the dummy that correspond to the occupant's waist, chest, etc. will be referred to as the dummy's waist, dummy's chest, etc. The same applies to other parts of the dummy that correspond to each part of the occupant.

[0028] The passenger attitude restraining device of the present invention will be described below in detail with respect to each of its constituent elements.

[0029] The occupant posture restraining device of the present invention is only required to include a lifting element, and may also include other components such as a seat belt and a seat.

[0030] Unless otherwise specified, the numerical ranges "x to y" described in this specification include the lower limit x and the upper limit y. Furthermore, these upper and lower limit values, as well as the numerical values listed in the examples, can be arbitrarily combined to form new numerical ranges. Furthermore, numerical values arbitrarily selected from any of the above numerical ranges can be used as the upper and lower limit values of a new numerical range.

[0031] The occupant position restraint device of the present invention includes a lifting element that is activated upon a vehicle impact.

[0032] As described above, the lifting element may be any element that lifts the seat surface of the seat upward so that the dummy will hunch over on the seat when an impact occurs, and the details thereof are not particularly limited.

[0033] Here, the inventor of the present invention discovered that in order to make the dummy hunch over on the seat when an impact occurs, it is effective to lift the buttocks of the dummy instead of lifting the thighs of the dummy.

[0034] When the thighs of the dummy are lifted, the dummy simply lifts its thighs and falls forward, so the dummy's spine is less likely to bend and it is less likely to hunch over.

[0035] On the other hand, when the buttocks of a dummy are lifted, a force acts on the dummy's spine from below toward above. Because the vertical distance between the dummy's buttocks and the lifting element, which is the source of this force, is very close, this force acts directly on the dummy's buttocks, and the speed at which the buttocks are lifted is high. However, to parts of the dummy that are farther vertically from the lifting element, the force is transmitted while being buffered via the dummy's spine. Therefore, the farther a part of the dummy is from the lifting element in the vertical direction, the slower the lifting speed of that part and the amount of lift of that part also becomes smaller. Because the dummy's lower back is closer to the dummy's buttocks than the dummy's shoulders, and the dummy falls forward when an impact occurs, lifting the dummy's buttocks is thought to cause the dummy's shoulders to move closer to the dummy's lower back, resulting in a hunched posture.

[0036] Because the dummy behaves in the same way as an occupant, if the buttocks of the dummy seated in the seat can be lifted and the dummy can hunch over in the event of an impact, the occupant sitting in the seat can also hunch over in the same way, which can prevent or suppress the occupant's chest from being pressed hard by the tension of the shoulder straps, thereby reducing the burden on the occupant in the event of an impact.

[0037] The vertical distance between the waist point and the chest point, for example, the vertical distance between the waist acceleration sensor and the chest acceleration sensor, should be smaller than normal when an impact occurs. In other words, the dummy will be in a forward-leaning position at this time, and the vertical distance between the waist point and the chest point will be closer when an impact occurs than normal, i.e., before the impact. This vertical distance between the waist point and the chest point is preferably 10 mm or more, 20 mm or more, or 30 mm or more.

[0038] The above-mentioned "normal state" more specifically means a state in which the dummy is properly seated. As already mentioned, the waist point and chest point can be interpreted as the waist acceleration sensor and chest acceleration sensor of the dummy.

[0039] Furthermore, the above-mentioned "vertical distance between the waist point and chest point at the time of impact" can be measured under conditions that comply with the frontal collision test stipulated by the US New Car Assessment Program (US NCAP).For reference, the US NCAP frontal collision test is a full-flap frontal collision test in which a test vehicle with dummies in the driver's and passenger's seats is slammed into a concrete wall (fixed barrier) at a speed of 56 km / h.

[0040] In order to efficiently and reliably lift the buttocks of a dummy seated in a seat and cause the dummy to assume a hunched posture when an impact occurs, it is preferable that the lifting element satisfy one of the following conditions [1] to [3], and it is more preferable that the lifting element satisfy more than one of the following conditions.

[0041] [1] Quickly lift the dummy's buttocks when an impact occurs. [2] When an impact occurs, lift the dummy's buttocks from directly below. [3] When an impact occurs, the dummy's buttocks are raised high.

[0042] [1] In order for the lifting element to quickly lift the buttocks of the dummy when an impact occurs, it is preferable that the lifting element lift the seat surface upward at a speed that lifts the lumbar point (e.g., lumbar acceleration sensor) of the dummy by 10 mm or more in 25 milliseconds when an impact occurs. It is even more preferable that the lifting element lift the seat surface upward at a speed that lifts the lumbar point by 20 mm or more in 25 milliseconds.

[0043] An example of a lifting element that can quickly lift the buttocks of the dummy as in the above item [1] is a seat cushion airbag device that is disposed below the seat surface of the seat.

[0044] The seat cushion airbag device deploys and inflates upon impact, lifting the seat surface of the seat and thereby lifting the buttocks of the dummy. The seat cushion airbag device has a bag-shaped airbag and an inflation fluid source connected to the airbag and supplying inflation fluid to the airbag. Hereinafter, unless otherwise specified, the term "airbag" in this specification refers to the airbag in the seat cushion airbag device.

[0045] As the inflation fluid generating source, it is preferable to use a so-called inflator that generates gas as the inflation fluid, but in some cases, it is also possible to use a source that generates inflation fluid other than gas, such as liquid or gel.

[0046] The inflation fluid generating source may be any device for supplying inflation fluid to the airbag, such as a so-called pyrotechnic inflator having a gas generating agent that generates gas as inflation fluid, or a so-called hybrid inflator that supplies gas contained in a high-pressure container by rupturing a bulkhead of the high-pressure container. The inflation fluid generating source may be located entirely outside the airbag, or partly or entirely inside the airbag.

[0047] The inflation fluid generating source can quickly start supplying inflation fluid to the airbag at a relatively large flow rate, so that the seat cushion airbag device as a lifting element can quickly lift the seat surface upward upon impact, and ultimately the buttocks of the dummy.

[0048] The airbag is disposed in a seat portion of a vehicle seat. The seat portion is the portion of the seat where an occupant sits and may include a seat support portion and a cushion-like seat portion supported by the seat support portion. In addition to the seat portion, the seat may also include, for example, a backrest, armrests, etc.

[0049] In this specification, a seat may be any seat in which an occupant can sit, and may be, for example, a front seat such as a driver's seat or a passenger seat, or a rear seat.

[0050] The airbag is disposed below the seat surface in the seat portion of a vehicle seat, and when deployed and inflated, the airbag itself deforms and pushes the seat surface upward. Such an airbag is preferably stored in the seat in a folded or collapsed state under normal conditions, and the material of the airbag is preferably selected to be foldable and deployable.

[0051] As a specific material for the airbag, it is preferable to select a material that is flexible and has high strength, and for example, a woven fabric made of high-strength resin fibers such as polyester or polyamide can be particularly preferably used.

[0052] When a seat cushion airbag device is used as a lifting element, depending on the position of the airbag relative to the seat, it is possible to lift the dummy's buttocks from directly below as in [2] above. Note that "directly below" here does not only mean a position vertically below the dummy's buttocks, but also includes a position where the crossing angle with respect to the vertically downward direction is within 30°.

[0053] Specifically, the position of the airbag relative to the seat is preferably below the seat surface of the seat and between the center and front end of the seat bottom in the front-rear direction.

[0054] When the airbag is deployed in the above position, the region of the seat between the center and front end in the fore-and-aft direction is deformed upward as the airbag deploys. At least a portion of the region of the seat between the center and front end in the fore-and-aft direction coincides with the region from the ischium to the thighs of a dummy seated in the seat. Therefore, at this time, the region from the ischium to the thighs of the dummy seated in the seat of the seat, i.e., the buttocks, are lifted from directly below. Similarly, at this time, the buttocks of an occupant seated in the seat of the seat are lifted from directly below.

[0055] The position of the airbag relative to the seat is preferably rearward of the front 1 / 5 position in the front-to-rear direction of the seat, rearward of the front 1 / 4 position in the front-to-rear direction of the seat, or rearward of the front 1 / 3 position in the front-to-rear direction of the seat. In these cases, the airbag is positioned near the buttocks of the dummy seated in the seat, making it possible to lift the dummy's buttocks from directly below in the event of an impact.

[0056] As mentioned above in [3], in order to raise the buttocks of the dummy high when an impact occurs, it is preferable to deform the airbag in the seat cushion airbag device, which is the lifting element, significantly upward when deployed and inflated, and to raise the upward position of the top to a certain extent.

[0057] As shown in Figures 10 and 11, the airbag in a typical seat cushion airbag device has a flat shape formed by sewing together an upper sheet 50u that forms the top 11t of the airbag and a lower sheet 50l that forms the bottom of the airbag. In the airbag, the seam between the upper sheet 50u and the lower sheet 50l is formed along the entire circumferential edge of the upper sheet 50u and the lower sheet 50l. Hereinafter, the airbag will be referred to as a flat airbag as necessary.

[0058] The flat airbag 11F described above has a flat shape with almost no thickness in the up-down direction when it is in a normal state, i.e., when it is not deployed or inflated. When the flat airbag 11F deploys and inflates upon an impact, the lower sheet 50l expands downward to form a bottom portion 11b, and then the upper sheet 50u expands upward to form a top portion 11t, as shown in Fig. 11 .

[0059] In order to allow this type of flat airbag 11F to deform significantly upward when deployed and inflated, and to raise the position of the top portion 11t in the upward direction to some extent, it is necessary to enlarge the outer shape thereof.

[0060] Specifically, the size of the flat airbag in a normal state is preferably 80% or more of the width of the seat portion of the seat, and more preferably 90% or more.

[0061] As mentioned above, the flat airbag used in the seat cushion airbag device, which is a lifting element, needs to have a large external shape in the normal state. However, depending on the shape of the seat bottom, it may be difficult to install such a large flat airbag.

[0062] In other words, in order to increase the degree of freedom in arranging the airbag, it is preferable to use an airbag that deforms significantly upward when deployed and inflated, even if its outer shape in the normal state is not particularly large.

[0063] Specifically, the airbag preferably has a shape that has sides between a top and a bottom when deployed and inflated. More preferably, the airbag has upright walls extending in the vertical direction in at least two opposing regions of the sides. Hereinafter, this airbag will be referred to as a three-dimensional airbag as necessary.

[0064] The three-dimensional airbag is connected to an inflation fluid generating source and is deployed and inflated when inflation fluid is supplied to the interior thereof. When deployed and inflated, having sides between a top and a bottom; It can be said that the seat cushion airbag has standing walls extending in the up-down direction in at least two opposing regions of the side portions.

[0065] In a three-dimensional airbag, the upright walls included in the side portions extend in the vertical direction when the airbag is deployed and inflated. Therefore, the upright walls guide the deformation direction of the airbag so that the top of the airbag is positioned higher in the upward direction when the airbag is deployed and inflated. It can also be said that the standing wall contributes to causing the airbag to deform significantly upward when deployed and inflated.

[0066] With a three-dimensional airbag having such upright walls on the sides, even if its external shape is not particularly large in its normal state, the top of the airbag is positioned sufficiently high when deployed. As a result, when a seat cushion airbag device having such a three-dimensional airbag is used as a lifting element, it is possible to lift the buttocks of a dummy seated in a seat high in the event of an impact, thereby efficiently causing the dummy to hunch over.

[0067] In the three-dimensional airbag, the side portions may be formed only when the airbag is deployed and inflated, or may be formed during normal operation in addition to when the airbag is deployed and inflated.

[0068] Here, the top of a three-dimensional airbag refers to the region of the three-dimensional airbag mounted on the seat cushion when deployed and inflated, including the upper end and its peripheral edge that smoothly connects to the upper end. The size and shape of the top may be either linear or planar as long as they correspond to the shape of the three-dimensional airbag.

[0069] The top of a three-dimensional airbag may extend three-dimensionally in the vertical direction, and the vertical length is not particularly limited because it varies depending on the shape of the three-dimensional airbag. In some cases, the side portions including the standing walls are formed continuously with the top, and the boundaries between the top and the side portions or the standing walls are unclear.

[0070] In contrast, the bottom portion refers to the area of the three-dimensional airbag mounted on the seat portion that includes the lower end portion when deployed and inflated and the peripheral portion that smoothly continues to the lower end portion. The size and shape of the bottom portion may also be either linear or planar as long as they correspond to the shape of the three-dimensional airbag.

[0071] The bottom portion may also extend three-dimensionally in the vertical direction, and the vertical length thereof is not particularly limited because it varies depending on the shape of the three-dimensional airbag. In some cases, the side portions including the standing walls are formed continuously with the bottom portion, and the boundaries between the bottom portion and the side portions or the standing walls are unclear.

[0072] The side portions of the three-dimensional airbag are located between the top and bottom portions when the airbag is deployed and inflated. When the airbag is deployed and inflated, the top and bottom portions are located at different positions in the up-down direction. Therefore, the side portions can be said to be located between the top and bottom portions in the up-down direction of the three-dimensional airbag. The side portions are located between the top and bottom portions over the entire circumferential circumference of the three-dimensional airbag. In this specification, the circumferential direction of a three-dimensional airbag means the direction in which the sides of the three-dimensional airbag extend.

[0073] The top, bottom and side portions described above are also present in a flat airbag.

[0074] The three-dimensional airbag has vertically extending upright walls in at least two opposing regions of the side portions.

[0075] The standing wall of the three-dimensional airbag may form only a part of the side portion or may form the entire side portion. In other words, the standing wall may be present between the top and bottom of only a part of the three-dimensional airbag in the circumferential direction, or may be present between the top and bottom of the three-dimensional airbag over the entire circumferential direction.

[0076] The upright walls of a three-dimensional airbag are gusset-like, that is, they are added to the portions of a flat airbag formed only by an upper sheet and a lower sheet that are not thick enough, and can also be said to be in the form of a so-called insert cloth.

[0077] For example, the standing walls of a three-dimensional airbag may be integrally molded with the top and / or bottom portions, or the standing walls may be molded separately from the top and / or bottom portions and then joined to the top and / or bottom portions to form an integral unit.

[0078] In this specification, the term "joining" includes the concepts of sewing together with sewing thread, binding together using various joining materials such as staples, bonding using adhesive, and welding.

[0079] 12 and 13, the three-dimensional airbag 11T may be formed by joining and integrating a gusset body 50s, which is separate from an upper sheet 50u and a lower sheet 50l, to the upper sheet 50u and the lower sheet 50l. When the three-dimensional airbag 11T is deployed and inflated, a part of the gusset body 50s forms the standing wall 20.

[0080] 12 and 13 are explanatory diagrams that schematically explain one embodiment of a three-dimensional airbag, and more specifically, they schematically explain the state of the three-dimensional airbag when cut along the width direction, i.e., the left-right direction shown in each diagram.

[0081] The three-dimensional airbag 11T shown in Fig. 12 is folded or crushed in a normal state as shown in Fig. 13. The three-dimensional airbag 11T unfolds and inflates as shown in Fig. 12 when inflation fluid is supplied from an inflation fluid generating source (not shown).

[0082] 12, in the three-dimensional airbag 11T, the standing wall 20 extends in the vertical direction when deployed and inflated. The standing wall 20 thereby guides the deformation direction of the three-dimensional airbag 11T so that the top portion 11t is positioned higher in the upward direction.

[0083] 12 and 13, in the three-dimensional airbag 11T, the upper end of the standing wall 20 has a seam (more specifically, seam 30) between the standing wall 20 and the top portion 11t, and the lower end of the standing wall 20 has a seam (i.e., seam 30) between the standing wall 20 and the bottom portion 11b. The seam between the standing wall 20 and the top portion 11t can be rephrased as a seam between the gusset member 50s and the upper sheet 50u. The seam between the standing wall 20 and the bottom portion 11b can be rephrased as a seam between the gusset member 50s and the lower sheet 50l.

[0084] The portion of the standing wall 20 located near the joint 30 has higher rigidity than the other portion of the standing wall 20 (referred to as a general portion 21 of the standing wall 20 as needed). Therefore, the portion of the standing wall 20 near the joint is less likely to deform than the general portion of the standing wall 20, and its shape is more likely to be maintained.

[0085] Therefore, in the three-dimensional airbag 11T of this embodiment, when it is deployed and inflated, the general portion 21 of the standing wall 20 deforms preferentially, guiding the deformation direction of the three-dimensional airbag 11T so that the upward position of the top 11t becomes higher.

[0086] Therefore, in this case, even if the external shape of the three-dimensional airbag 11T in the normal state is not so large, the top portion 11t thereof will be positioned sufficiently high in the upward direction when deployed and inflated. In this embodiment, substantially the entire upper sheet 50u forms the top portion 11t of the three-dimensional airbag 11T.

[0087] Also, for example, as shown in FIG. 14, the gusset body 50s and the upper sheet 50u in the three-dimensional airbag 11T may be integrally molded, and the integrally molded body of the upper sheet 50u and the standing wall 20 and the lower sheet 50l may be sewn together to be integrated.

[0088] In the three-dimensional airbag 11T of this embodiment, it can also be said that the standing wall 20 is configured as a part of the upper sheet 50u. In this embodiment, the standing wall 20 can also be said to function as a gusset between the top 11t and the bottom 11b.

[0089] For reference, Figures 14 and 15 are explanatory diagrams that schematically explain one embodiment of a three-dimensional airbag, and more specifically, they schematically explain the state of the three-dimensional airbag when cut along the width direction.

[0090] The three-dimensional airbag 11T of this embodiment is also folded or crushed in a normal state as shown in Fig. 15. When inflation fluid is supplied from an inflation fluid generating source (not shown), the three-dimensional airbag 11T unfolds and inflates as shown in Fig. 14.

[0091] As shown in Figure 15, when the three-dimensional airbag 11T is deployed and inflated, the vertical position of the top 11t, which is part of the upper sheet 50u, is raised, and the vertically extending standing wall 20, which is another part of the upper sheet 50u, guides the deformation direction of the three-dimensional airbag 11T in the vertical direction.

[0092] Therefore, even in this case, even if the internal pressure of the three-dimensional airbag 11T is not particularly high when it is deployed and inflated, the top portion 11t of the three-dimensional airbag 11T will be positioned sufficiently high in the upward direction. This not only ensures that the deployed three-dimensional airbag 11T reaches a sufficiently high height when an impact occurs, but also increases the speed at which the height of the three-dimensional airbag 11T increases when an impact occurs, which has the advantage of enabling the dummy's buttocks to be quickly lifted when an impact occurs.

[0093] 16, for example, the top portion 11t, the bottom portion 11b, and the standing wall 20 of a three-dimensional airbag 11T may each be divided into a plurality of segments. The segment of the top portion 11t, the segment of the standing wall 20 continuous with the segment of the top portion 11t, and the segment of the bottom portion 11b continuous with the segment of the standing wall 20 may be integrally molded to form a single airbag segment 11d.

[0094] In the three-dimensional airbag 11T of this embodiment, it can be said that the four airbag segments 11d are joined together and integrated to form the three-dimensional airbag 11T.

[0095] At the top 11t of the three-dimensional airbag 11T of this embodiment, there is a seam 30 between a portion of one airbag segment 11d that forms the top 11t and a portion of another adjacent airbag segment 11d that forms the top 11t.

[0096] In addition, in the bottom 11b of the three-dimensional airbag 11T of this embodiment, there is a seam 30 between the part of one airbag segment 11d that forms the bottom 11b and the part of another adjacent airbag segment 11d that forms the bottom 11b.

[0097] Furthermore, in the standing wall 20 of the three-dimensional airbag 11T of this embodiment, there is a seam 30 between a portion of a certain airbag segment 11d that forms the standing wall 20 and a portion of another adjacent airbag segment 11d that forms the standing wall 20.

[0098] In this case, too, when the three-dimensional airbag 11T, which is folded or crushed in the normal state, deploys and inflates, the vertically extending upright wall guides the deformation direction of the three-dimensional airbag 11T so that the upward position of the top 11t becomes higher.

[0099] Therefore, even in this case, even if the external shape of the three-dimensional airbag in the normal state is not so large, the position above the top of the three-dimensional airbag when deployed and inflated will be sufficiently high.

[0100] The standing wall is preferably folded inward or outward of the three-dimensional airbag in the normal state, which has the advantage that the length of the standing wall in the vertical direction is increased when the airbag is deployed and inflated, and that the three-dimensional airbag can be easily crushed or folded so as to reduce its outer shape in the normal state.

[0101] As described above, when the standing wall is folded inward or outward of the three-dimensional airbag in the normal state, it is also preferable to provide a seam or joint at the fold of the standing wall, which increases the rigidity of the fold and makes it easier for the fold to maintain its shape in the normal state.

[0102] The three-dimensional airbag may have vertically extending walls in at least two opposing regions of the side portions, and the vertical length of the vertically extending walls is not particularly limited. The vertically extending walls may be continuous throughout the entire vertical direction, or may have a seam anywhere in the vertical direction.

[0103] In a three-dimensional airbag, in order to raise the top of the airbag in the upward direction when the airbag is deployed and inflated, it is preferable to make the vertical length of the upright wall, i.e., the height of the upright wall, long.

[0104] The vertical length of the upright wall of the three-dimensional airbag is preferably 120 mm or more when the internal pressure is 175 kPa during deployment. There is no particular upper limit to the vertical length of the upright wall, but if one were to be forced to specify, it would be good if it were 300 mm or less.

[0105] In a three-dimensional airbag, when the standing walls are present in two opposing regions of the side, the standing walls in the two regions may have the same shape or different shapes, and in this case, the lengths of the standing walls in the vertical direction may be the same or different.

[0106] When the vertical wall is present around the entire circumferential direction of the three-dimensional airbag, the vertical length of the vertical wall may be the same or different around the entire circumferential direction. In order to suppress the submarine phenomenon described above, it is preferable that the vertical length of the front portion of the vertical wall be longer than the vertical length of the rear portion.

[0107] As described above, the standing wall may be integrally molded with the top and / or bottom portions. However, it is more preferable that the standing wall be molded separately from the top and bottom portions and then joined to the top and / or bottom portions. By sandwiching the general portion of the standing wall between the highly rigid portions, i.e., the joint between the top and the standing wall and the joint between the bottom and the standing wall, the force that causes the general portion to deform in the vertical direction during deployment is less likely to be transmitted from the general portion toward the top portion and from the general portion toward the bottom portion. For example, when the general portion deforms in the vertical direction during deployment, it is possible that the upper sheet and the lower sheet may also bend and deform accordingly. Such bending and deformation of the upper sheet and the lower sheet may hinder the vertical deformation of the general portion.

[0108] By sandwiching the general portion at the seam, deformation of the general portion in the vertical direction is not easily hindered, and as a result, even if the internal pressure during deployment is relatively low, the vertical length of the three-dimensional airbag is sufficiently large, and the three-dimensional airbag rises upward at a high speed upon impact, thereby enabling the dummy's buttocks to be lifted high and quickly upon impact.

[0109] In the case of a three-dimensional airbag, it is also preferable to make the length of the three-dimensional airbag in the width direction longer to some extent in order to raise the buttocks of a dummy seated in a seat higher.

[0110] Specifically, in the normal state, the length of the three-dimensional airbag in the width direction is preferably 280 mm or more, or the size of the three-dimensional airbag in the normal state is preferably 70% or more of the width direction length of the seat portion, which is 100%.

[0111] The length of the three-dimensional airbag in the front-rear direction is not particularly limited, and may be approximately the same as the length in the width direction or may be longer than the length in the width direction. However, if the three-dimensional airbag is made compact, the weight of the three-dimensional airbag can be reduced.

[0112] For this reason, it is preferable that the length of the three-dimensional airbag in the front-rear direction is shorter than the length in the width direction. In other words, the three-dimensional airbag has a longitudinal direction and a lateral direction, and it is preferable that the longitudinal direction is aligned with the width direction of the seat portion.

[0113] Specifically, the length of the three-dimensional airbag in the front-rear direction is preferably 25% or more of the length of the three-dimensional airbag in the width direction.

[0114] Furthermore, in order to raise the buttocks of a dummy seated in a seat, it is preferable that, when deployed and inflated, the area of the three-dimensional airbag that corresponds to the dummy's buttocks and the area further outward in the width direction be positioned higher than the area that corresponds to the dummy's sitting bones.

[0115] In other words, the three-dimensional airbag is preferably placed in the seat with its longitudinal direction aligned with the width of the seat, and the top of the three-dimensional airbag has raised portions at both longitudinal ends, which can be said to be located higher than the longitudinal center portion when deployed and inflated.

[0116] Specifically, in a three-dimensional airbag, it is preferable that the above-mentioned protruding portion and the central portion in the longitudinal direction are spaced apart in the vertical direction by 5 mm or more when deployed and inflated.

[0117] In a three-dimensional airbag, the top and bottom may be connected by a tether. A tether is a member having a shape such as a string, a belt, or a thread, and is also called a tether or a strap. By connecting the top and bottom with a tether, the upward position of the top can be controlled with high precision during deployment. This is useful for lifting the buttocks of a dummy seated in a seat.

[0118] Similarly, in a three-dimensional airbag, it is also preferable to connect opposing standing walls, in other words, paired standing walls, with a tether. Connecting the standing walls with a tether has the advantage that the relative positions of the standing walls can be controlled with high precision when the airbag is deployed and inflated.

[0119] When the three-dimensional airbag has this configuration, it is particularly preferable that the upright walls are located at both ends of the three-dimensional airbag in the longitudinal direction, and that the longitudinal direction of the three-dimensional airbag is aligned with the width direction of the seat portion. In this case, by precisely controlling the width of the three-dimensional airbag when deployed, it is possible to raise the buttocks of a dummy seated in a seat.

[0120] Furthermore, [2] it is also useful to employ at least a part of the seat bottom as a part of the lifting element in order to lift the buttocks of the dummy from directly below when an impact occurs.

[0121] For example, the lifting element may include a seat portion including a seat surface of a seat, in which case at least a part of the seat portion may be displaced upward when an impact occurs. As described above, the seat portion is a part of the seat bottom of the seat and is supported by the seat support portion, which is also a part of the seat bottom. The seat portion is cushion-shaped and includes a seat surface. The seat portion can also be referred to as the part that comes into contact with the occupant's buttocks.

[0122] The seat portion may be formed as a single member, or may be formed as multiple separate pieces. For example, the seat portion may be divided into front and rear sections between the front end and the rear end. In this case, the lifting element may include all of the multiple seat portion sections, or may include only some of the multiple seat portion sections. In other words, when the seat portion is formed as multiple separate pieces, only some of the separate pieces may move upward in the event of an impact, or all of the separate pieces may move upward in the event of an impact.

[0123] The lifting element has at least a portion of the seat portion and, in addition to the at least a portion of the seat portion, a lifting drive portion for displacing the at least a portion of the seat portion upward.

[0124] The lifting drive unit may raise the position of the entire seat unit or only a part of the seat unit when an impact occurs. If the entire seat unit or a part of the seat unit raises its position, the buttocks of a dummy seated on the seat can be lifted from directly below.

[0125] In this case, the lifting drive unit may apply force to the front end of the seat to tilt the front end upward, or may apply force to the rear end of the seat to tilt the rear end upward, or may lift the entire seat upward.

[0126] When the seat portion is composed of multiple separate parts, the lifting drive unit may lift upward a front separate part including the front end of the seat portion, or may lift upward a rear separate part including the rear end of the seat portion. Alternatively, a force may be applied to the rear end of the front split body to tilt the rear end of the front split body upward, or a force may be applied to the front end of the rear split body to tilt the front end of the rear split body upward. Furthermore, the seat may be configured with three or more divisions arranged in a front-to-rear direction, and a middle division between a front division and a rear division may be lifted upward by the lifting drive unit. There may be only one middle division, or there may be multiple middle divisions. The lifting drive unit may lift the entire middle division upward, or may tilt the front end or the rear end of the middle division upward.

[0127] The lifting drive unit is not particularly limited as long as it can change the position of at least a portion of the seat unit upward as described above. Examples of the lifting drive unit include, but are not limited to, a unit that includes an electric motor or an inflator as a drive source. It is preferable that the lifting drive unit operates quickly when an impact occurs, and it is particularly preferable that the lifting drive unit include an inflator as a drive source.

[0128] The lifting drive unit may have, in addition to the drive source, a driven unit that moves the drive source to change the position of at least a part of the seat unit upward. The driven unit may be the seat unit itself, may be integrated with the seat unit, or may be the seat support unit that supports the seat unit.

[0129] The seat support portion that functions as the follower portion is preferably, for example, a seat bar or a seat pan.

[0130] Of these, the seat bar is a long member that is located below the seat surface and spans the width of the seat.It supports the seat portion from below and contributes to improving the strength of the seat portion, especially in the width direction.

[0131] When the seat bar is a driven part, the seat bar driven by the drive source changes position upward when an impact occurs, and at least a portion of the seat part is lifted upward by the seat bar, changing position.

[0132] The seat pan is a plate-shaped member located below the seat surface of the seat and extending in the width and front-to-back directions of the seat. It supports the seat portion from below and contributes to improving the strength of the seat portion in the width and front-to-back directions.

[0133] When the seat pan is a driven part, at least a portion of the seat pan driven by the drive source changes position upward when an impact occurs. The entire seat pan may change position upward, or, for example, the seat pan may tilt around one end and change position upward at the other end. When at least a portion of the seat pan changes position upward, at least a portion of the seat portion is lifted upward by the seat pan and changes position.

[0134] For example, if the drive source is an electric motor, it is preferable to interpose a drive force transmission mechanism, such as a rack and pinion mechanism or a cam mechanism, between the electric motor as the drive source and the seat bar or seat pan as the driven parts. The drive force transmission mechanism is part of the lifting drive unit.

[0135] The drive force transmission mechanism converts the drive force of the drive source into an upward force and transmits it to the seat bar or the seat pan, thereby changing the position of at least a portion of the seat bar or the seat pan in the upward direction.

[0136] As mentioned above, an inflator is a device that generates various inflation fluids such as gas. If the driving source is an inflator, it is preferable to interpose an airbag-like driving force transmission mechanism between the inflator as the driving source and the seat bar or seat pan as the driven part. This driving force transmission mechanism is also part of the lifting drive unit.

[0137] The airbag-shaped driving force transmission mechanism is deployed and inflated by the driving force of the driving source, i.e., by inflation fluid, and thereby can change the position of at least a portion of the seat bar or seat pan in the upward direction.

[0138] When the lifting drive unit directly moves at least a portion of the seat upward as described above, it is preferable to interpose a drive force transmission mechanism between the drive source and the seat unit. In this case, the lifting drive unit can be said to use the seat unit itself as a driven unit.

[0139] When at least a portion of the seat bottom is used as a lifting element as described above, increasing the operating speed of the lifting drive unit when an impact occurs allows the dummy's buttocks to be lifted quickly [1] when an impact occurs. In this case, too, it is preferable that the lifting element lift the seat surface at a speed that lifts the dummy's lumbar point (e.g., lumbar acceleration sensor) by 10 mm or more in 25 milliseconds when an impact occurs. It is even more preferable that the lifting element lift the seat surface at a speed that lifts the lumbar point by 20 mm or more in 25 milliseconds.

[0140] Furthermore, when at least a portion of the seat is used as part of the lifting element as described above, by significantly changing the position of at least a portion of the seat upward using the lifting drive unit, it is possible to lift the dummy's buttocks high when an impact occurs.

[0141] The passenger attitude restraining device of the present invention will be described below by way of a specific example.

[0142] Example 1 The passenger attitude restraint device of the first embodiment includes a seat cushion airbag device as a lifting element and a seat. FIG. 1 is an explanatory diagram illustrating a schematic view of the passenger attitude restraint device of the first embodiment as viewed from above. FIGS. 2 and 3 are explanatory diagrams illustrating a schematic view of the passenger attitude restraint device of the first embodiment as viewed from the side. FIG. 2 shows the passenger attitude restraint device of the first embodiment when the airbag is in a normal state, and FIG. 3 shows the passenger attitude restraint device of the first embodiment when the airbag is deployed and inflated upon an impact. FIG. 4 is a diagram illustrating a schematic view of the airbag in the passenger attitude restraint device of the first embodiment as viewed from above, FIG. 5 is a diagram illustrating a schematic view of the airbag in the passenger attitude restraint device of the first embodiment as viewed from the side, and FIG. 6 is an explanatory diagram illustrating a schematic view of the airbag in the passenger attitude restraint device of the first embodiment as viewed from the side and rear.

[0143] Hereinafter, in Example 1, the terms "upper", "lower", "left", "right", "front" and "rear" refer to the upper, lower, left, right, front and rear shown in the drawings. The left-right direction coincides with the width direction.

[0144] The occupant posture restraining device of the first embodiment includes a seat cushion airbag device 1 as a lifting element, and a seat 90. As shown in FIG. 1, the seat cushion airbag device 1 includes a three-dimensional airbag 11T and an inflation fluid generating source 10. The inflation fluid generating source 10 generates inflation fluid.

[0145] The seat cushion airbag device 1 in the occupant posture restriction device of the first embodiment is mounted on a vehicle seat 90, and more specifically, is disposed below a seat portion 95 in a seat portion 91 of the seat 90. Since a seat surface 93 of the seat portion 91 is formed by the upper surface of the seat portion 95, it can also be said that the seat cushion airbag device 1 in the occupant posture restriction device of the first embodiment is disposed below the seat surface 93 in the seat portion 91.

[0146] The three-dimensional airbag 11T is located above a seat bar 92 that spans the width of the seat portion 91 near the center in the front-rear direction. Therefore, the seat cushion airbag 11 can be said to be disposed in the front region, which is the region between the center and the front end of the seat portion 91 in the front-rear direction.

[0147] The inflation fluid generating source 10 is disposed inside the three-dimensional airbag 11T and further forward than the seat bar 92.

[0148] The inflation fluid generating source 10 in the seat cushion airbag device 1 is an inflator that generates gas as inflation fluid, and is connected to a control device (not shown) for deploying and inflating the three-dimensional airbag 11T, and operates by receiving a supply of electric power. The control device is an electronic control unit (ECU) of the vehicle.

[0149] As shown in FIGS. 4 and 5, the three-dimensional airbag 11T is made up of an upper sheet 50u, a lower sheet 50l, two gusset members 50s, and a tether 60 sewn together.

[0150] The upper sheet 50u forms the top portion 11t of the three-dimensional airbag 11T, and the lower sheet 50l forms the bottom portion 11b of the three-dimensional airbag 11T.

[0151] The upper sheet 50u, the lower sheet 50l, and the gusset body 50s are each made of polyester woven fabric. The upper sheet 50u and the lower sheet 50l are substantially identical in shape, with their longitudinal directions extending left and right and their lateral directions extending front and rear. Therefore, the longitudinal direction of the seat cushion airbag 11 can be said to be along the width direction.

[0152] 4, 5, and 6, the upper sheet 50u and the lower sheet 50l are sewn together at the front and rear portions of their peripheries to form an integrated unit. It can also be said that the upper sheet 50u and the lower sheet 50l are sewn together at both ends in the shorter direction to form an integrated unit.

[0153] The gusset members 50s are disposed at both longitudinal ends of the three-dimensional airbag 11T. The upper portions of the gusset members 50s are sewn together with the longitudinal end of the upper sheet 50u to form an integrated unit. The lower portions of the gusset members 50s are sewn together with the longitudinal end of the lower sheet 50l to form an integrated unit.

[0154] The seams 30 of the upper sheet 50u, the lower sheet 50l, and the two gusset members 50s are formed along the entire circumferential edge of the upper sheet 50u and the lower sheet 50l, as shown in Fig. 4. It can also be said that the seams 30 are formed along the entire circumferential edge of each gusset member 50s, as shown in Fig. 5. This gives the three-dimensional airbag 11T a generally box-like shape.

[0155] At both ends of the three-dimensional airbag 11T in the short direction, the seam 30 between the upper sheet 50u and the lower sheet 50l and the surrounding area form part of the side portion 11s. At both ends of the long direction of the three-dimensional airbag 11T, the portion between the seam 30 between the upper sheet 50u and the gusset member 50s and the seam 30 between the lower sheet 50l and the gusset member 50s forms the remainder of the side portion 11s. This portion also forms the upright wall 20 extending in the vertical direction.

[0156] 4, in the three-dimensional airbag 11T, the top portion 11t and the bottom portion 11b are connected by a tether 60. The tether 60 is disposed inside the three-dimensional airbag 11T.

[0157] The three-dimensional airbag 11T is folded in a normal state. When inflation fluid is supplied from the inflation fluid generating source 10, the three-dimensional airbag 11T is deployed and inflated as shown in FIGS.

[0158] The three-dimensional airbag 11T is placed in the seat portion 91 with its longitudinal direction aligned with the left-right direction, which is the width direction. The longitudinal center portion of the top portion 11t and the longitudinal center portion of the bottom portion 11b are connected by a tether 60. Therefore, when deployed and inflated, the longitudinal center portion of the top portion 11t is located lower in the upward direction than both longitudinal end portions of the top portion 11t.

[0159] 6, the top portion 11t of the three-dimensional airbag 11T has raised portions 40 at both ends in the longitudinal direction thereof. The raised portions 40 are located above a central portion 41 in the longitudinal direction when the airbag is deployed and inflated.

[0160] The three-dimensional airbag 11T has vertically extending standing walls 20 in regions of the side portions 11s located at both longitudinal ends thereof. The standing walls 20 deform in the vertical direction when deployed and inflated. Therefore, the deformation direction of the three-dimensional airbag 11T when deployed and inflated is guided in the vertical direction by the standing walls 20.

[0161] Therefore, in the three-dimensional airbag 11T, the top 11t is positioned high upward when deployed and inflated, and as a result, the occupant posture control device of Example 1 uses the lifting element, i.e., the seat cushion airbag device 1, to lift the seat surface 93 of the seat 90 high upward, thereby making it possible to lift the buttocks 99b of the dummy 99 seated on the seat 90 high.

[0162] Furthermore, even if the internal pressure of the three-dimensional airbag 11T is not particularly high when deployed, the top portion 11t is positioned sufficiently high in the upward direction. As a result, the occupant posture restriction device of the first embodiment can use the lifting element, i.e., the seat cushion airbag device 1, to quickly lift the buttocks 99b of the dummy 99 seated on the seat 90.

[0163] 2, the dummy 99 has a waist acceleration sensor SW on its waist 99w and a chest acceleration sensor SC on its chest 99c. The waist acceleration sensor SW is located at the waist point of the dummy 99, and the chest acceleration sensor SC is located at the chest point of the dummy 99.

[0164] The seat cushion airbag device 1 in the occupant posture restriction device of the first embodiment deploys and inflates the three-dimensional airbag 11T at a speed that lifts the lumbar point of the dummy 99, i.e., the lumbar acceleration sensor SW, by 20 mm or more in 25 milliseconds. In other words, the speed at which the three-dimensional airbag 11T deploys and inflates is high. This also enables the lifting element in the occupant posture restriction device of the first embodiment to lift the buttocks 99b of the dummy 99 seated on the seat 90 high and quickly.

[0165] In the occupant posture restriction device of the first embodiment, the above cooperation causes the vertical distance H between the waist acceleration sensor SW and the chest acceleration sensor SC of the dummy 99, in other words, the vertical distance between the waist point and the chest point, to be shorter than normal when an impact occurs. Specifically, in the occupant posture restriction device of the first embodiment, the vertical distance H between the waist acceleration sensor SW and the chest acceleration sensor SC is shorter than normal by 10 mm or more when an impact occurs.

[0166] That is, with the occupant posture restriction device of the first embodiment, the dummy 99 seated in the seat 90 as shown in Figure 2 will bend its back forward and assume a hunched posture when an impact occurs as shown in Figure 3. Naturally, the occupant seated in the seat 90 will also be in a hunched posture when an impact occurs.

[0167] If the dummy 99 is hunched over, the shoulder straps 94s will not be aligned with the chest 99c of the dummy 99, but will be suspended between the shoulders 99s and waist 99w of the dummy 99. Therefore, a gap will be created between the shoulder straps 94s and the chest 99c, which is located between the shoulders 99s and waist 99w. This prevents or suppresses the tension of the shoulder straps 94s from strongly pushing against the chest 99c of the dummy 99, thereby preventing or suppressing the chest of the occupant from being strongly pushed against. In other words, the occupant posture restriction device of the first embodiment can reduce the burden on the occupant when an impact occurs.

[0168] When an impact occurs, the waist of the dummy wearing the seat belt first moves forward due to inertia, and then moves back. In some cases, the waist of the dummy repeats this forward and backward movement multiple times. According to the seat cushion airbag device 1 of the occupant posture restriction device of the first embodiment, the state in which the vertical distance H between the lumbar acceleration sensor SW and the chest acceleration sensor SC of the dummy 99 is smaller than normal is maintained until the initial forward movement of the lumbar point of the dummy stops, specifically for 55 milliseconds or more. This maintains the hunched posture of the dummy 99 for a sufficiently long time, and it is possible to reliably avoid or suppress the chest 99c of the dummy 99 from being strongly pressed by the tension of the shoulder straps 94s.

[0169] Example 2 The passenger posture restriction device of the second embodiment has a seat portion and a lifting drive portion as a lifting element instead of a seat cushion airbag device. Other than this, the passenger posture restriction device of the second embodiment is substantially the same as the passenger posture restriction device of the first embodiment. FIG. 7 is an explanatory diagram for schematically explaining an occupant posture restriction device according to the second embodiment. The passenger attitude restriction device of the second embodiment will be described below, focusing on the differences from the first embodiment.

[0170] As shown in FIG. 7, the passenger attitude restriction device of the second embodiment has a seat portion 95 and a lifting drive portion 15 as the lifting element 1.

[0171] More specifically, the seat 90 in the occupant posture restraint device of the second embodiment has a seat portion 95 and a seat support portion 96. The seat support portion 96 is a portion of the sitting portion 91 of the seat 90 that supports the seat portion 95 from below. The seat portion 95 is tiltable relative to the seat support portion 96 around a tilting axis (not shown) located at the rear of the seat portion 95 so that its front end faces upward.

[0172] The lifting drive unit 15 is disposed between the seat portion 95 and the seat support portion 96, and has a drive source 16 formed of an inflator, and an airbag-shaped drive force transmission mechanism 17. The drive force transmission mechanism 17 is disposed at a front position between the seat portion 95 and the seat support portion 96.

[0173] The drive source 16, i.e., the inflator, is connected to an ECU in the same manner as various airbag devices, and generates inflation fluid when an impact occurs. The inflation fluid is supplied to the airbag-shaped drive force transmission mechanism 17. The drive force transmission mechanism 17, to which inflation fluid is supplied, deploys and inflates between the seat support portion 96 and the seat portion 95. As the drive force transmission mechanism 17 deploys and inflates, the seat portion 95 is lifted from below and tilted so that its front end faces upward. This enables the lifting element 1 to lift high the buttocks 99b of the dummy 99 seated on the seat 90.

[0174] The lifting element 1 in the occupant posture restriction device of the second embodiment also deploys and inflates the driving force transmission mechanism 17 at a speed that lifts the waist point, i.e., the waist acceleration sensor, of the dummy 99 by 20 mm or more in 25 milliseconds. Therefore, the occupant posture restriction device of the second embodiment can also lift the buttocks 99b of the dummy 99 seated in the seat 90 high and quickly.

[0175] In the occupant posture restraint device of the second embodiment, the vertical distance H between the waist acceleration sensor and the chest acceleration sensor of the dummy 99 is also 10 mm or more shorter when an impact occurs than under normal conditions.

[0176] Therefore, even with the occupant posture restriction device of the second embodiment, the dummy 99 seated in the seat 90 will hunch over when an impact occurs. Similarly, the occupant seated in the seat 90 will also hunch over when an impact occurs.

[0177] As a result, the occupant posture restriction device of Example 2 can prevent or suppress the occupant's chest from being pressed hard when an impact occurs, thereby reducing the burden on the occupant when an impact occurs.

[0178] Example 3 The occupant posture restriction device of the third embodiment includes a seat bar as a lifting element, and is generally the same as the occupant posture restriction device of the second embodiment except for the lifting element. FIG. 8 is an explanatory diagram for schematically explaining an occupant posture restraint device according to the third embodiment. The passenger attitude restriction device of the third embodiment will be described below, focusing on the differences from the second embodiment.

[0179] As shown in FIG. 8, the occupant posture restriction device of the third embodiment has, as the lifting element 1, a seat bar 96b that is a part of a seat support portion 96, and a lifting drive portion 15.

[0180] The seat bar 96b is a metal member with high strength and rigidity. The seat bar 96b is long and spans the width of the seat portion 91 at the lower and front portion of the seat portion 95. The position of the seat bar 96b can be changed upward relative to the other portion of the seat support portion 96 (referred to as a general support portion 96g).

[0181] The lifting drive unit 15 is disposed below the seat bar 96b and includes a drive source 16 formed of an inflator and an airbag-shaped drive force transmission mechanism 17. The drive force transmission mechanism 17 is disposed directly below the seat bar 96b and above the general support portion 96g.

[0182] When an impact occurs, the driving source 16, i.e., the inflator, generates inflation fluid and supplies the inflation fluid to the airbag-shaped driving force transmission mechanism 17, which then deploys and inflates below the seat bar 96b. As the driving force transmission mechanism 17 deploys and inflates, the seat bar 96b moves upward, and the seat surface 93 of the seat portion 95 is lifted upward. As a result, the occupant posture restriction device of the third embodiment also makes it possible to lift the buttocks 99b of the dummy 99 seated on the seat 90.

[0183] The lifting element 1 in the occupant posture restriction device of the third embodiment also deploys and inflates the driving force transmission mechanism 17 at a speed that lifts the waist acceleration sensor of the dummy 99 by 20 mm or more in 25 milliseconds. Therefore, the occupant posture restriction device of the third embodiment can also lift the buttocks 99b of the dummy 99 seated on the seat 90 high and quickly. In the occupant posture restraint device of the third embodiment, the vertical distance H between the waist acceleration sensor and the chest acceleration sensor of the dummy 99 is also 10 mm or more shorter when an impact occurs than under normal conditions.

[0184] Therefore, even with the occupant posture restriction device of the third embodiment, the dummy 99 seated in the seat 90 will hunch over when an impact occurs. Similarly, the occupant seated in the seat 90 will also hunch over when an impact occurs.

[0185] As a result, the occupant posture restriction device of Example 3 can prevent or suppress the occupant's chest from being pressed hard when an impact occurs, thereby reducing the burden on the occupant when an impact occurs.

[0186] Example 4 The occupant posture restraint device of the fourth embodiment includes a seat pan as a lifting element, and is generally the same as the occupant posture restraint device of the second embodiment except for the lifting element. FIG. 9 is an explanatory diagram for schematically explaining an occupant posture restraint device according to the fourth embodiment. The passenger attitude restriction device of the fourth embodiment will be described below, focusing on the differences from the second embodiment.

[0187] As shown in FIG. 9, the occupant posture restriction device of the fourth embodiment has, as the lifting element 1, a seat pan 96p that is a part of a seat support portion 96, and a lifting drive portion 15.

[0188] The seat pan 96p is a metal member with high strength and rigidity. The seat pan 96p is flat and extends in the front-to-rear and width directions of the seat cushion 91 below and at the rear of the seat portion 95. The seat pan 96p can tilt around a tilting shaft (not shown) located at the rear of the seat pan 96p so that its front end faces upward. Therefore, the seat pan 96p can be said to be able to change its position upward relative to the general support portion 96g.

[0189] The lifting drive unit 15 is disposed below the seat pan 96p, and has a drive source 16 formed of an inflator, and an airbag-shaped drive force transmission mechanism 17. The drive force transmission mechanism 17 is disposed below the front side of the seat pan 96p.

[0190] When an impact occurs, the drive source 16, i.e., the inflator, generates inflation fluid and supplies the inflation fluid to the airbag-shaped drive force transmission mechanism 17, which deploys and inflates below the front of the seat pan 96p. As the drive force transmission mechanism 17 deploys and inflates, the front end of the seat pan 96p tilts upward, and the seat surface 93 of the seat portion 95 is lifted upward. As a result, the occupant posture restriction device of the fourth embodiment also makes it possible to lift the buttocks 99b of the dummy 99 seated on the seat 90 from directly below.

[0191] The lifting element 1 in the occupant posture restriction device of the fourth embodiment also deploys and inflates the driving force transmission mechanism 17 at a speed that lifts the waist acceleration sensor of the dummy 99 by 20 mm or more in 25 milliseconds. Therefore, the occupant posture restriction device of the fourth embodiment can also quickly and high lift the buttocks 99b of the dummy 99 seated on the seat 90 from directly below. In the occupant posture restraint device of the fourth embodiment, the vertical distance H between the waist acceleration sensor and the chest acceleration sensor of the dummy 99 is also 10 mm or more shorter when an impact occurs than under normal conditions.

[0192] Therefore, even with the occupant posture restriction device of the fourth embodiment, the dummy 99 seated in the seat 90 will hunch over when an impact occurs. Similarly, the occupant seated in the seat 90 will also hunch over when an impact occurs.

[0193] As a result, the occupant posture restriction device of Example 4 can prevent or suppress the occupant's chest from being pressed hard when an impact occurs, thereby reducing the burden on the occupant when an impact occurs.

[0194] Although the present invention has been described above, the present invention is not limited to the above-described embodiments, etc., and it is possible to implement the present invention by appropriately extracting and combining elements described in the embodiments, etc., and to make various modifications within the scope that does not deviate from the spirit of the present invention. Furthermore, the specification of the present invention discloses not only the citation relationships of the claims at the time of filing but also the technical idea of appropriately combining the matters described in the claims. [Explanation of symbols]

[0195] 1: Seat cushion airbag device, lifting element 10: Expanding fluid source 11T: Three-dimensional airbag 15: Lifting drive unit 90: Seat 91: Seat part 93: Seat 96p: Seat pan 96b: Seat bar 96: Seat support part 99:THOR50M Dummy 99b: Dummy buttocks 99c: Dummy chest 99w: Dummy waist SW: Waist acceleration sensor (waist point) SC: Chest acceleration sensor (chest point) H: Vertical distance between the waist acceleration sensor and the chest acceleration sensor (vertical distance between the waist point and the chest point)

Claims

1. An occupant posture restriction device for restricting the posture of an occupant seated in a seat when a vehicle impact occurs, a lifting element that is activated upon the occurrence of the impact; The lifting element is an occupant posture control device that lifts the seat surface of the seat upward so that, when the impact occurs, the vertical distance between the waist point and chest point of a THOR50M dummy seated in the seat becomes smaller than usual.

2. 2. The occupant posture restraint device according to claim 1, wherein the lifting element lifts the seat surface of the seat upward at a speed that lifts the lumbar point of the THOR50M dummy by 20 mm or more in 25 milliseconds upon the occurrence of the impact.

3. 3. The occupant posture restraining device according to claim 1, wherein the lifting element is a seat cushion airbag device that is disposed below the seat surface of the seat and has an airbag that deploys and inflates when the impact occurs.

4. the lifting element has a seat portion including the seating surface of the seat; 3. The occupant posture restriction device according to claim 1, wherein at least a portion of the seat portion is displaced upward when the impact occurs.

5. The lifting element is located below the seat surface of the seat and has a seat bar spanning the width of the seat, 3. The occupant posture restraining device according to claim 1, wherein the seat bar is displaced upward when the impact occurs.

6. The lifting element includes a seat pan located below the seat surface of the seat and extending in the width direction and the fore-aft direction of the seat; 3. The occupant posture restraining device according to claim 1, wherein at least a portion of the seat pan is displaced upward when the impact occurs.

7. An occupant posture restriction device as described in claim 1 or claim 2, wherein the lifting element lifts the seat upward so that, when the impact occurs, the vertical distance between the waist point and the chest point of the THOR50M dummy is maintained smaller than normal until the initial forward movement of the waist point relative to the vehicle stops.

8. 3. The occupant posture restraint device according to claim 1, further comprising the seat and a seat belt in addition to the lifting element.

Images