VEHICLE OCCUPANT RESTRAINT DEVICE

Abstract

A vehicle occupant restraint device (10) comprising: a seat belt (22) configured to restrain an occupant (P) on the vehicle seat (12); a belt support air cushion (42) configured to inflate and deploy at least between a shoulder belt (22A) and a shoulder (Ps) of the occupant (P) upon an incident of a frontal collision of a vehicle by being supplied with gas from a gas generator (32) to move toward a front of the vehicle following the occupant (P) moving toward the front of the vehicle and to restrain at least the shoulder (Ps) of the occupant (P);and a gas supply pipe (34) having a first end portion connected to the gas generator (32), a second end portion connected to the belt support air cushion (42), and a predetermined region on one side of the second end portion, the predetermined region being configured to extend toward the front of the vehicle following movement of the belt support air cushion (42);

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The present invention relates to a vehicle occupant restraint device. 2. Description of the related art

[0002] An occupant protection device that suppresses a sudden increase in a restraining force on a passenger's head in the event of a frontal collision of a vehicle is known in the related art (see, for example, Japanese Unexamined Patent Application Laid-Open No. 2017-124759 (JP 2017-124759 A)). The occupant protection device includes an airbag and a connecting fabric. The airbag deploys in a region including a front side and both the right and left sides of the passenger's head to cover the head. The connecting fabric has an expansion rate equal to or lower than that of the airbag. A first end portion of the connecting fabric is connected to a front portion of the airbag, and a second end portion of the connecting fabric is connected to a force limiting mechanism provided within a headrest. SUMMARY OF THE INVENTION

[0003] However, in the occupant protection device described above, the forward deployment impulse of the airbag is assisted and controlled by the force limiting mechanism provided in the headrest, thus requiring a complex mechanism in the headrest. As described above, there is still room for improvement so that the occupant can be effectively restrained in the event of a frontal collision of the vehicle without requiring a complicated mechanism.

[0004] The present invention provides a vehicle occupant restraint device capable of effectively restraining an occupant in the event of a frontal collision of a vehicle, even with a simple design.

[0005] A first aspect of the invention relates to a vehicle occupant restraint device comprising a seat belt, a belt-supporting air cushion, and a gas supply pipe. The seat belt is configured to restrain an occupant seated on a vehicle seat. The belt-supporting air cushion is configured to inflate and deploy, upon the occurrence of a frontal collision of a vehicle, at least between a shoulder strap in the seat belt and a shoulder of the occupant by being supplied with gas from a gas generator, to move toward a front of the vehicle following the occupant P moving toward the front of the vehicle due to an inertial force, and to restrain at least the occupant's shoulder. The gas supply pipe has a first end portion connected to the gas generator and a second end portion connected to the belt-supporting air cushion.A predetermined portion of the gas supply pipe on the second end portion side is designed to extend toward the front of the vehicle following the movement of the belt support air cushion.

[0006] According to the invention of the first aspect, the seatbelt support airbag inflates and deploys at least between the shoulder belt in the seatbelt and the occupant's shoulder by being supplied with the gas from the inflator during a frontal collision of a vehicle, moves toward the front of the vehicle, follows the occupant moving toward the front of the vehicle due to inertial force, and restrains at least the occupant's shoulder. That is, the seatbelt shoulder belt serves as a member that receives a reaction force from the seatbelt support airbag.In this case, the predetermined range of the gas supply pipe on the side of the second end portion of the gas supply pipe, the first end portion of which is connected to the gas generator and the second end portion of which is connected to the belt support air bag, extends toward the front of the vehicle following the movement of the belt support air bag.

[0007] Therefore, regardless of the occupant's body type, the support air cushion can be continuously held at least between the shoulder belt and the occupant's shoulder, and at least the occupant's shoulder can be effectively restrained from a first half to a second half of the occupant restraint, while suppressing or preventing the occurrence of a problem such as the breakage of the gas supply pipe. Furthermore, the inflated and deployed support air cushion forms a predetermined gap between the shoulder belt and the occupant's chest.

[0008] As described above, according to the aspect of the invention, even with a simple configuration in which the predetermined range of the gas supply pipe on the side of the second end portion connected to the belt support airbag of the gas supply pipe is extendable, the occupant is effectively restrained in the event of a frontal collision of the vehicle. The phrase "in the event of a frontal collision" of the vehicle mentioned here includes a time at which a frontal collision of the vehicle is predicted (predicted) to be inevitable.

[0009] The vehicle occupant restraint device may further comprise a covering member. A bellows-shaped expandable portion is provided in the predetermined area of ​​the gas supply tube. The expandable portion of the gas supply tube and the folded belt support air cushion are housed in the covering member.

[0010] In the configuration, the predetermined portion of the gas supply tube on the second end portion side connected to the belt support air cushion serves as a bellows-shaped expandable portion, and the expandable portion of the gas supply tube and the folded belt support air cushion are housed within the member. That is, the expandable portion and the belt support air cushion are provided outside the vehicle seat. Therefore, it is not necessary to provide a complicated structure inside the vehicle seat. Furthermore, since the expandable portion and the belt support air cushion are concealed by the covering member, the appearance of the vehicle seat is not damaged.

[0011] The bellows-shaped expandable portion may be configured to shorten when the bellows-shaped expandable portion is housed in the cover member. The bellows-shaped expandable portion may be configured to elongate and expand to a predetermined outer diameter when the belt support airbag inflates and deploys. The bellows-shaped expandable portion may be configured to further elongate and contract to a predetermined inner diameter when the belt support airbag moves toward the front of the vehicle.

[0012] With this design, the bellows-shaped expandable portion is shortened when the expandable portion is housed in the covering member. Therefore, a housing space is reduced and the housing performance is improved. As the belt support airbag inflates and unfolds, the bellows-shaped expandable portion elongates and expands to a predetermined outer diameter. Therefore, the gas is supplied to the belt support airbag quickly, sufficiently, and stably. As the belt support airbag moves toward the front of the vehicle, the bellows-shaped expandable portion further elongates and contracts to a predetermined inner diameter. Therefore, the gas supplied to the belt support airbag is less likely to return to one side of the inflator.

[0013] The expandable portion of the gas supply tube may be provided with a stent element that limits excessive expansion.

[0014] In this design, the expandable portion of the gas supply tube is provided with a stent element that limits excessive expansion. Therefore, a decrease in gas supply capacity (gas pressure) due to excessive expansion of the expandable portion of the gas supply tube can be suppressed.

[0015] In addition, the expandable portion of the gas supply pipe may be formed in a crushed shape along the shoulder strap when the expandable portion is accommodated in the covering member.

[0016] With this design, the expandable portion of the gas supply tube is formed in a crushed shape along the shoulder belt when the expandable portion is housed in the covering member. Therefore, the expandable portion of the gas supply tube can be used as a cushioning member, so that the wearability of a shoulder belt part can be improved when wearing the seat belt.

[0017] The shoulder strap can be used movably by means of a guide element housed in the cover element and must not come into contact with the expandable section of the gas supply pipe.

[0018] In this design, the shoulder belt is movably inserted through the guide element housed in the cover element and does not come into contact with the expandable portion of the gas supply pipe. Therefore, when fastening or unfastening the seat belt, no external force, such as a tensile load, is exerted on the expandable portion of the gas supply pipe, and the seat belt can be moved smoothly.

[0019] A force-limiting mechanism may be provided in a retractor that winds the seat belt. The expandable portion of the gas supply tube may be designed to extend under a load less than the force-limiting load of the force-limiting mechanism.

[0020] In this design, the force-limiting mechanism is provided in the retractor that winds the seat belt. The expandable portion of the gas supply tube extends under a load lower than the force-limiting load of the force-limiting mechanism. Therefore, the occurrence of a problem in which the gas supply tube interferes with the operation of the force-limiting mechanism can be suppressed or prevented. As a result, the occupant's behavior can be easily controlled.

[0021] The gas generator can be installed together with the reel into the backrest of the vehicle seat.

[0022] With this design, the gas generator, along with the retractor, is embedded into the seatback of the vehicle seat. Therefore, the individual components comprising the vehicle occupant restraint system can be installed solely through the vehicle seat, including the seat belt and the like, and workability during vehicle assembly is improved.

[0023] A bellows-shaped expandable portion may be provided in the predetermined region of the gas supply pipe. The expandable portion may be provided between the seat back and the belt support air cushion.

[0024] As described above, the vehicle occupant restraint device according to the aspect of the present disclosure can effectively restrain the occupant in the event of a frontal collision of the vehicle even with a simple configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Features, advantages and technical and industrial significance of embodiments of the invention are described below with reference to the accompanying drawings, in which like characters designate like elements and in which: Fig. 1 is a schematic perspective view showing a state in which a belt support air bag of a vehicle occupant restraint device according to a first embodiment inflates and deploys; Fig. 2 is a schematic front view showing the state in which the belt support air bag of the vehicle occupant restraint device according to the first embodiment is inflated and deployed; Fig. 3 is a schematic side view showing the state of inflation and deployment of the belt support air bag of the vehicle occupant restraint device according to the first embodiment; Fig. 4 is a schematic front view showing a normal state of the belt support air bag of the vehicle occupant restraint device according to the first embodiment; Fig. 5 is a schematic side view showing the normal state of the belt support air bag of the vehicle occupant restraint device according to the first embodiment; Fig. 6 is a schematic side sectional view showing an internal structure of the belt support air bag of the vehicle occupant restraint device according to the first embodiment when the belt support air bag is inflated and deployed; Fig. 7 is a schematic, partially enlarged sectional view showing the structure of a gas supply pipe of the vehicle occupant restraint device according to the first embodiment; Fig. 8A is a schematic cross-sectional view showing a state in which the gas supply pipe of the vehicle occupant restraint device according to the first embodiment expands in diameter; Fig. 8B is a schematic cross-sectional view showing a state in which the gas supply pipe of the vehicle occupant restraint device according to the first embodiment contracts in diameter; Fig. 9A is a schematic side view showing a state before a gas supply pipe of a vehicle occupant restraint device according to a modification example of the first embodiment extends; Fig. 9B is a schematic side view showing a state in which the gas supply pipe of the vehicle occupant restraint device according to the modification example of the first embodiment is extended; Fig. 9C is a schematic side view showing a state after the gas supply pipe of the vehicle occupant restraint device according to the modification example of the first embodiment has been extended; Fig. 10 is a schematic enlarged sectional view showing a normal state of the gas supply pipe of the vehicle occupant restraint device according to the modified example of the first embodiment; Fig. 11A is a schematic side view showing a state before inflation and deployment of the belt support air bag of the vehicle occupant restraint device according to the first embodiment; Fig. 11B is a schematic side view showing a state in which the belt support air bag of the vehicle occupant restraint apparatus according to the first embodiment is inflated and deployed; Fig. 12A is a schematic side view showing a state immediately after inflation and deployment of the belt support air bag of the vehicle occupant restraint device according to the first embodiment; Fig. 12B is a schematic side view showing a state in which the belt support air bag of the vehicle occupant restraint apparatus according to the first embodiment moves forward; Fig. 13 is a schematic perspective view showing a state in which a belt support air bag of a vehicle occupant restraint device according to a second embodiment inflates and deploys; Fig. 14 is a schematic front view showing the state when the belt support air bag of the vehicle occupant restraint device according to the second embodiment inflates and deploys; and Fig. 15 is a schematic side view showing the state of inflation and deployment of the belt support air bag of the vehicle occupant restraint device according to the second embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For convenience of description, with respect to arrows shown in each of the drawings, an arrow UP indicates an upward direction of a vehicle and a vehicle seat, an arrow FR indicates a forward direction of the vehicle and the vehicle seat, and an arrow RH indicates a rightward direction of the vehicle and the vehicle seat. Therefore, in the following description, in a case where the up-down, front-back, and right-left directions are described without particular mention, the up-down, front-back, and right-left directions in the vehicle and the vehicle seat are illustrated. Moreover, the right-left direction is the same as the vehicle width direction and the seat width direction. First embodiment

[0027] First, a first embodiment is described. As in Fig. 1 to 5, a vehicle occupant restraint device 10 according to the first embodiment is provided on a vehicle seat 12. The vehicle seat 12 is a front seat or a rear seat of a vehicle (automobile), and here, the front seat is the vehicle seat 12. The vehicle seat 12 includes a seat cushion 14, a seat back 16 rotatably provided at a rear end portion of the seat cushion 14 about a seat width direction as the axial direction, and a headrest 18 movable up and down at an upper end portion of the seat back 16.

[0028] In Fig. 1 and the like, an impact test dummy (human body manikin) is shown sitting on the seat cushion 14 of the vehicle seat 12 as a model of an occupant (seated person) to be protected. The dummy is, for example, an AM50 (50th percentile of an adult U.S. male) (Hybrid III) dummy for frontal collision testing. The dummy sits in a standard sitting posture determined by a collision test method, and the vehicle seat 12 is located in a reference position corresponding to the sitting posture. The test dummy is hereinafter referred to as "occupant P."

[0029] As in the Fig. As shown in FIGS. 1 to 5, the occupant P sitting on the seat cushion 14 of the vehicle seat 12 is restrained on the vehicle seat 12 by a seat belt (webbing) 22 provided in a seat belt device 20. The seat belt device 20 is a three-point seat belt device and is a so-called seat-integrated seat belt device. Furthermore, in the following description, a part of the seat belt 22 extending from a shoulder Ps to a abdomen Pt of the occupant P is referred to as a shoulder belt 22A.

[0030] On an outer side in the vehicle width direction (first end portion side in the seat width direction) on an upper end surface of the seat back 16, a panel 24 serving as an outlet of a seat belt 22 is provided, and on an inner side in the vehicle width direction (second end portion side in the seat width direction) of the seat cushion 14, a buckle 26 for fastening a tongue 25 provided on the seat belt 22 is provided (see Fig. 2). A retractor 28 for winding a first end portion of the seat belt 22 is fixed to a lower portion of a side frame (not shown) provided on the outer side in the vehicle width direction inside the seat back 16 (see Fig. 3). The retractor 28 is provided with a belt tensioning mechanism and a force limiting mechanism.

[0031] The vehicle seat 12 is provided with an airbag device 30. The device 30 includes a gas generator 32 embedded in a side portion 16S of the seat back 16 on the outer side in the vehicle width direction, a belt support air cushion 42 housed in a cover member 40 (see Fig. 4, Fig. 5 and Fig. 11A) in a folded state, and a gas supply pipe 34 (described later) connecting the belt support air bag 42 and the gas generator 32 and supplying gas from the gas generator 32 to the belt support air bag 42.

[0032] As in the Fig. 4, Fig. 5 and Fig. 11A, the covering member 40 is fixed by sewing or the like to a cloth holder member (not shown) that holds a guide member 38 through which the shoulder belt 22A is movably inserted. The covering member 40 covers the holding member, the folded belt support air bag 42 disposed on the occupant P side relative to the guide member 38, and an expandable portion 34A of the gas supply pipe 34, which will be described later, around the shoulder belt 22A facing the shoulder Ps of the occupant P. The covering member 40 is designed to be broken at least on the occupant P side when the belt support air bag 42 is inflated and deployed.

[0033] The guide member 38 is formed in a rectangular, flat, tubular shape, e.g., from a silicone-based resin material with high sliding properties, so that the shoulder strap 22A can move (slide) easily (see Fig. 10). The retaining member is fixed to a peripheral surface of the guide member 38, except for the side of the occupant P, with any fastening element. As shown in Fig. 6 and Fig. As shown in Fig. 10, the guide member 38 is configured to prevent the shoulder belt 22A from coming into contact with the expandable portion 34A of the gas supply pipe 34. Furthermore, the guide member 38 is configured to prevent an external force from acting on the expandable portion 34A of the gas supply pipe 34 when the seat belt 22 is fastened or unfastened.

[0034] The gas generator 32 is, for example, a gas-tight (cold) cylindrical gas generator with a substantially cylindrical shape. The gas generator is designed to inflate gas by being activated by a control device (not shown) provided in the vehicle when a frontal collision of the vehicle is detected or a frontal collision is predicted to be inevitable by a collision sensor (not shown) including a camera or the like (hereinafter referred to as "in the event of a frontal collision of the vehicle").

[0035] That is, the control device is electrically connected to the inflator 32 and the collision sensor and is configured to activate the inflator 32 based on information from the collision sensor in the event of a frontal collision of the vehicle. One type of frontal collision of the vehicle in which the control device activates the inflator 32 includes, in addition to a full-overlap frontal collision, an offset frontal collision, such as an oblique collision or a small-overlap collision.

[0036] The gas generator 32, for example, is mounted together with the retractor 28 on the side frame of the seat back 16 on the outer side in the vehicle width direction substantially in the axial direction from top to bottom, and a first end portion of the cylindrical gas supply tube 34 is communicatively connected to an ejection port, which is an upper end portion of the gas generator 32. A second end portion of the gas supply tube 34 protrudes from the seat back 16 on a side below the panel 24 and is connected to the belt support air cushion 42.

[0037] As in Fig. 6, the gas supply pipe 34 for supplying gas from the inflator 32 to the belt support air bag 42 is configured such that a part of the gas supply pipe 34 on one side of the belt support air bag 42 (second end portion side), that is, a predetermined area projecting from the seat back 16, serves as the expandable portion 34A configured to extend upon forward movement of the belt support air bag 42.

[0038] Specifically, the gas supply pipe 34 is integrally formed by connecting a first end portion of the expandable portion 34A, made of, for example, a heat-resistant elastomer resin, to an upper end portion of a main body pipe 34S made of resin or metal and embedded in the seat back 16. The first end portion of the expandable portion 34A is connected to the upper end portion of the main body pipe 34S by a clamp member 35 or the like.

[0039] As in the Fig. As shown in FIGS. 6 to 8B, the expandable portion 34A of the gas supply tube 34 protruding from the seat back 16 is formed in a bellows shape and has a three-layer structure that can be extended by a predetermined load. That is, the expandable portion 34A of the gas supply tube 34 includes an outer layer 34B formed in a bellows shape, an inner layer 34C in which a mesh-like metallic stent member 36 capable of limiting excessive expansion is embedded, and a silicone coating layer 34D provided between the outer layer 34B and the inner layer 34C.

[0040] Consequently, the expandable portion 34A of the gas supply pipe 34 is designed to elongate and expand to a predetermined outer diameter when the gas is supplied and the belt-supporting airbag 42 is inflated and deployed. Specifically, the expandable portion 34A is designed so that bellows-shaped valley portions, which protrude radially inward and are reduced in inner diameter when shortened, expand due to the deformation of a bellows-shaped knitted structure, thereby achieving rapid and sufficiently stable gas supply. The expandable portion 34A of the gas supply pipe 34 is designed to further expand and contract to a predetermined inner diameter when the belt-supporting airbag 42 is moved forward as the occupant P moves forward (see Fig. 8B).

[0041] That is, the gas supply tube 34 also functions as a check valve by contracting the expandable portion 34A in diameter, making it difficult for gas to flow back from the inside of the belt support air cushion 42. The expandable portion 34A of the gas supply tube 34 is designed to extend under a load less than the force limiting load of the force limiting mechanism provided in the retractor 28. The stent member 36 is not limited to a metal material, as long as the stent member 36 can withstand the expansion force of the tube during gas supply.

[0042] Furthermore, the expandable portion 34A of the gas supply tube 34 is not limited to the configuration in which the stent element 36 is provided in the inner layer 34C. The expandable portion 34A of the gas supply tube 34 may be configured as described above by being formed of an elastic body such as rubber, as shown in FIGS. Fig. 9A to 9C. That is, the expandable portion 34A of the gas supply pipe 34 is designed to elastically deform to expand as shown in Fig. 9B and Fig. 9C, only to extend when a tensile load is applied and that it is supported by an elastic restoring force as shown in Fig. 9A, returns to the original state when no tensile load is applied.

[0043] When the expandable portion 34A of the gas supply tube 34 is configured as in the case where the stent member 36 is provided, the expandable portion 34A can expand and unfold to a predetermined outer diameter when the gas is supplied and the belt support airbag 42 inflates and unfolds. Furthermore, when the belt support airbag 42 moves forward as the occupant P moves forward, the expandable portion 34A can elongate and contract to a predetermined inner diameter.

[0044] As in Fig. 4 and Fig. 5, the bellows-shaped portions of the expandable portion 34A are in a shortened state when the expandable portion 34A of the gas supply pipe 34 is accommodated in the cover member 40. In addition, the expandable portion 34A, as shown in Fig. 10, be formed in a crushed shape along an inner surface located on an occupant side P of the shoulder belt 22A. That is, both the expandable portion 34A of the gas supply tube 34 having the crushed shape and the folded belt support air bag 42 can be accommodated in the covering member 40.

[0045] The belt support air cushion 42 is formed in a bag shape by overlapping two layers of the base fabric in the front / rear direction, the two layers having a substantially rectangular shape in a front view in which the seat width direction is a longitudinal direction, and sewing peripheral edge portions of the two layers together. That is, as shown in FIGS. Fig. As shown in FIGS. 1 to 3, the belt support airbag 42, after inflation and deployment, is configured by a substantially cylindrical single chamber in which the seat width direction is the longitudinal direction (axial direction), and a length thereof in the axial direction is set to a length that can oppose the shoulder Ps of the occupant P in the front-rear direction. Each layer of the base fabric is formed of, for example, a polyamide- or polyester-based fabric material.

[0046] The belt support air bag 42 is configured to be supplied with gas from the inflator 32 via the gas supply pipe 34 extending through the side below the panel 24. As a result, the belt support air bag 42 inflates and expands to extend in the seat width direction at least between the shoulder belt 22A and the two shoulders Ps of the occupant P, and moves forward following the occupant P moving forward due to an inertial force in a manner of being pushed by the occupant P, thereby restraining at least the two shoulders Ps of the occupant P, including the collarbones.

[0047] In the vehicle occupant restraint device 10 according to the first embodiment having the configuration, an operation thereof will be described below. Fig. 1 to 3, 11B, 12A and 12B, the guide element 38 and the cover element 40 are not shown.

[0048] In the event of a frontal collision of the vehicle, the gas generator 32 is activated by the control of the device. That is, the gas is expelled from the gas generator 32. The gas expelled from the gas generator 32 is then guided through the gas supply pipe 34 into the belt support air cushion 42. That is, as shown in Fig. 11B, the gas is supplied into the interior of the belt support air bag 42 in a folded state, which is accommodated in the covering member 40 and arranged on the occupant side P (rear side) of the shoulder belt 22A.

[0049] Then, as in the Fig. 1 to 3 and 12A, the belt support air cushion 42 inflates and deploys to extend in the seat width direction between the shoulder belt 22A and the shoulder Ps of the occupant P. As a result, the inflated and deployed belt support air cushion 42 is located between the shoulder belt 22A and at least the two shoulders Ps of the occupant P, including the collarbones, in other words, behind the shoulder belt 22A and in front of the two shoulders Ps of the occupant P.

[0050] As in Fig. As shown in Fig. 12B, the belt support airbag 42 moves forward and follows the occupant P who moves forward due to the inertial force caused by an impact in the event of a frontal collision of the vehicle, and restrains at least both shoulders Ps of the occupant P, including the collarbones. That is, the shoulder belt 22A serves as a member that receives a reaction force of the belt support airbag 42.

[0051] At this time, the expandable portion 34A of the gas supply pipe 34 for supplying the belt support air bag 42 with the gas from the inflator 32 extends in the forward movement of the belt support air bag 42. Therefore, the belt support air bag 42 can be continuously held between the shoulder belt 22A and both shoulders Ps of the occupant P regardless of the physique of the occupant P, and at least both shoulders Ps of the occupant P can be effectively restrained from a first half to a second half of the occupant restraint, while the occurrence of a problem such as breakage (gas leakage) of the gas supply pipe 34 can be suppressed or prevented.

[0052] As described above, with the vehicle occupant restraint device 10 according to the first embodiment, even with a simple configuration in which the predetermined area portion of the gas supply pipe 34 on the belt support air bag 42 side serves as a bellows-shaped expandable portion 34A and is expandable following the forward movement of the occupant P, the occupant P can be effectively restrained in the event of a frontal collision of the vehicle.

[0053] Furthermore, the belt support air cushion 42 can be used to generate an appropriate restraining force for the shoulder Ps on an opposite shoulder belt side, to which the shoulder belt 22A is not attached, at an early stage. In other words, a local load introduction from the shoulder belt 22A to the occupant P can be distributed early on to both shoulders Ps by the belt support air cushion 42. Therefore, even with the simple design, the introduction of the local load from the shoulder belt 22A to a chest Pc of the occupant P can be reduced, and both shoulders Ps of the occupant P can be effectively restrained.

[0054] Furthermore, a thickness of the inflated and deployed belt support air cushion 42 allows the shoulder belt 22A to be lifted from the chest Pc of the occupant P, and a predetermined gap can be formed between the shoulder belt 22A and the chest Pc of the occupant P. Therefore, the local load input from the shoulder belt 22A to the chest Pc of the occupant P can be reduced. This can reduce an injury value of the chest caused by the inhibition of forward movement by the shoulder belt 22A, especially for occupants with relatively low chest resistance, such as women or the elderly.

[0055] The expandable portion 34A of the gas supply tube 34 is provided with the stent member 36, which limits excessive expansion. Therefore, a decrease in the gas supply capacity (gas pressure) due to excessive expansion of the expandable portion 34A of the gas supply tube 34 can be suppressed, and the expandable portion 34A can be prevented from inflating and rupturing. Furthermore, excessive inflation of the expandable portion 34A of the gas supply tube 34 near the head of the occupant P can also be suppressed or prevented.

[0056] The retractor 28 is provided with the force limiting mechanism. Here, the expandable portion 34A of the gas supply pipe 34 extends under a load lower than the force limiting load of the force limiting mechanism. Therefore, the occurrence of a problem in which the gas supply pipe 34 interferes with the operation of the force limiting mechanism can be suppressed or prevented. As a result, the behavior of the occupant P can be easily controlled.

[0057] In a normal state, the expandable portion 34A of the gas supply tube 34 and the folded belt support air bag 42 are housed in the cover member 40 in a state where they are located on an occupant P side of the guide member 38. That is, the expandable portion 34A of the gas supply tube 34 and the folded belt support air bag 42 are provided outside the vehicle seat 12. Therefore, it is not necessary to provide a complicated structure inside the vehicle seat 12.

[0058] In addition, the expandable portion 34A of the gas supply tube 34 and the folded belt support air cushion 42 are covered with the cover member 40 and concealed from the outside, so that the appearance of the vehicle seat 12 can be suppressed or damage can be prevented. Particularly in a case where the cover member 40 is a design cover, the effect is further improved. In a normal state, the cover member 40 can prevent unnecessary contact with the expandable portion 34A of the gas supply tube 34 or the folded belt support air cushion 42, thereby ensuring durability.

[0059] When the expandable portion 34A of the gas supply pipe 34 is accommodated in the covering member 40, the bellows-shaped portion is shortened (see Fig. 5). Therefore, an accommodation space near the shoulder Ps of the occupant P is reduced, and accommodation performance is improved. When the belt-supporting airbag 42 inflates and deploys, the bellows-shaped portion of the expandable part 34A of the gas supply pipe 34 elongates and expands to a predetermined outer diameter. Therefore, gas can be supplied to the belt-supporting airbag 42 quickly, sufficiently, and stably. As the belt-supporting airbag 42 moves forward, the bellows-shaped portion of the expandable part 34A of the gas supply pipe 34 further elongates and contracts to a predetermined inner diameter. Therefore, the gas supplied to the belt-supporting airbag 42 is less likely to return to one side of the inflator 32.

[0060] The expandable portion 34A of the gas supply pipe 34 can be accommodated in the covering member 40 in a crushed form along the inner surface located on the occupant side P of the shoulder belt 22A (see Fig. 10). Accordingly, the expandable portion 34A of the gas supply pipe 34 can be used as a cushioning member, so that the wearability of a part of the shoulder belt 22A when wearing the seat belt 22 can be improved.

[0061] The shoulder belt 22A is movably inserted through the guide member 38 housed in the cover member 40 and does not contact the expandable portion 34A of the gas supply pipe 34. Therefore, when fastening or unfastening the seat belt 22, no external force, such as a load, is applied to the expandable portion 34A of the gas supply pipe 34, and the seat belt 22 can be moved smoothly. Furthermore, the guide member 38 can also prevent the seat belt 22 from being incorrectly fastened in a twisted state.

[0062] The gas generator 32, together with the retractor 28, is embedded in the seatback 16 of the vehicle seat 12. That is, all components constituting the vehicle occupant restraint device 10, including the seat belt 22 and the like, are provided on the vehicle seat 12. Therefore, the installation of each of the components constituting the vehicle occupant restraint device 10 can be completed solely by the vehicle seat 12. As a result, the vehicle occupant restraint device 10 can be easily installed in the vehicle by simply mounting the vehicle seat 12, and the ease of installation during vehicle assembly can be improved. Second embodiment

[0063] Next, a second embodiment will be described. The same reference numerals are used for the same parts as in the first embodiment, and detailed descriptions (including common actions) will be omitted where appropriate.

[0064] As in the Fig. 13 to 15, in the second embodiment, only the shape of the belt support air bag differs from that of the first embodiment. That is, a belt support air bag 44 is formed in the shape of a bag by superimposing two layers of a base fabric in the front / back direction, the two layers having a substantially rectangular shape in a front view, and sewing peripheral edge portions of the two layers together, and a shape of the belt support air bag 44 after inflation and deployment has a substantially right-angled triangular shape in a front view, in which one side of the fastener 26 forms a hypotenuse. Each layer of the base fabric is formed of, for example, a polyamide- or polyester-based fabric material.

[0065] The belt support air cushion 44 is divided into a plurality of chambers (e.g. three stages) which extend along the seat width direction by a plurality of (e.g. two) retaining straps 46, 48 (see Fig. 15) provided within the belt support air cushion 44. Specifically, the two fabric-like straps 46, 48, in which the seat width direction is a longitudinal direction, are attached to the inside of the belt support air cushion 44 at a distance therebetween in the up-down direction. The straps 46, 48 are formed, for example, from a polyamide- or polyester-based fabric material.

[0066] An opening (not shown) is formed in an outer portion of the tether 46 in the vehicle width direction, and the gas can be supplied from an upper chamber 44U divided by the tether 46 to a middle chamber 44C. Similarly, an opening (not shown) is formed in an outer portion of the tether 48 in the vehicle width direction, and the gas can be supplied from the middle chamber 44C divided by the tether 48 to a lower chamber 44D. The upper chamber 44U and the middle chamber 44C are each provided with a check valve structure (not shown) for maintaining an internal pressure.

[0067] In the thus configured belt support air cushion 44, when the gas is supplied from the inflator 32 through the gas supply pipe 34, the gas is first supplied to the upper chamber 44U, and the upper chamber 44U inflates and expands. Then, when the inflated and expanded upper chamber 44U is closed by the check valve structure, the gas is supplied to the middle chamber 44C through the opening of the upper tether 46, and the middle chamber 44C inflates and expands. After that, when the inflated and expanded middle chamber 44C is closed by the check valve structure, the gas is supplied to the lower chamber 44D through the opening of the lower tether 48, and the lower chamber 44D inflates and expands.

[0068] As a result, the belt support air bag 44 is sequentially supplied with the gas from the upper chamber 44U to the lower chamber 44D through the middle chamber 44C and is arranged to inflate and deploy at least between the shoulder belt 22A and the chest Pc of the occupant P, in other words, behind the shoulder belt 22A and in front of the occupant P. The inflated and deployed belt support air bag 44 moves forward and follows the occupant P who moves forward due to an inertial force caused by an impact in a frontal collision of the vehicle, and restrains at least the chest Pc of the occupant P. That is, in this case too, the shoulder belt 22A serves as a member that receives a reaction force of the belt support air bag 44.

[0069] With such a belt support air cushion 44, a local load exerted by the shoulder belt 22A on the chest Pc of the occupant P is distributed and reduced over a large area of ​​the chest Pc of the occupant P. Therefore, an injury value of the chest caused by the inhibition of forward movement by the shoulder belt 22A can be reduced, particularly for occupants with relatively low chest resistance, such as women or elderly persons.

[0070] Furthermore, with the belt support air cushion 44, the occupant P can be effectively restrained, for example, even when the occupant P sitting on the vehicle seat 12, e.g., on a driver's or front passenger's seat during autonomous driving, assumes a seating position far rearward from a steering wheel (not shown) or from a frontal collision airbag (not shown) that inflates and deploys toward a front of the occupant P. That is, with the belt support air cushion 44, the occupant P can be effectively restrained regardless of the seating position of the vehicle seat 12 in the event of a frontal collision of the vehicle.

[0071] In the belt support air cushion 44, the upper chamber 44U inflates and deploys first. Therefore, a position of the shoulder belt 22A can be stabilized, and a predetermined gap can be efficiently formed between the shoulder belt 22A and the occupant P. Therefore, the inflation and deployment of each chamber, from the upper chamber 44U to the middle chamber 44C to the lower chamber 44D, can be performed smoothly.

[0072] Although the vehicle occupant restraint device 10 according to the present embodiment has been described with reference to the drawings, the vehicle occupant restraint device 10 according to the present embodiment is not limited to the example shown and can be suitably modified within the scope that does not deviate from the gist of the present invention. For example, the second end portion of the gas supply pipe 34 can be designed to protrude through the panel 24.

[0073] The expandable portion 34A of the gas supply pipe 34 is not limited to the layers (three layers) and may be configured, for example, as a single layer. The expandable portion 34A of the gas supply pipe 34 is not limited to being formed in a bellows shape. For example, the outer layer 34B included in the expandable portion 34A of the gas supply pipe 34 may be formed of knitted fibers, as long as the outer layer 34B has sufficient expansion properties or an effect of suppressing excessive expansion.

[0074] The cover member 40 can accommodate at least the expandable portion 34A of the gas supply tube 34 and the folded belt support air cushion 42, and, for example, a lower end portion of the guide member 38 can protrude from the cover member 40. In the present embodiment, the guide member 38 is also housed in the cover member 40 in such a case.

[0075] The belt support air cushions 42, 44 are not limited to the design in which two layers of the base fabric are overlapped and the peripheral edge portions are stitched, but may have a design in which three or more layers of the base fabric are used and their peripheral edge portions are stitched. The material of the guide member 38 is not limited to the silicone-based resin material with high lubricity, and other materials with excellent lubricity may also be used. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2017-124759

[0002] JP 2017-124759 A

[0002]

Claims

[1] Vehicle occupant restraint device comprising: a seat belt (22) designed to restrain an occupant (P) sitting on a vehicle seat (12) to the vehicle seat (12); a belt support air cushion (42) configured to inflate and deploy at least between a shoulder belt (22A) in the seat belt (22) and a shoulder (Ps) of the occupant (P) by being supplied with gas from a gas generator (32), in an incident of a frontal collision of a vehicle, to move toward a front of the vehicle, following the occupant (P) moving toward the front of the vehicle due to an inertial force, and to restrain at least the shoulder (Ps) of the occupant (P); and a gas supply pipe (34) having a first end portion connected to the gas generator (32) and a second end portion connected to the belt support air cushion (42), wherein a predetermined portion of the gas supply pipe (34) on a side of the second end portion is configured to extend following a movement of the belt support air cushion (42) toward the front of the vehicle. [2] A vehicle occupant restraint device according to claim 1, further comprising a cover member (40), wherein: a bellows-shaped expandable portion (34A) is provided in the predetermined region of the gas supply pipe (34); and the expandable portion (34A) of the gas supply pipe (34) and the belt support air cushion (42) which is folded are accommodated in the cover member (40). [3] Vehicle occupant restraint device according to claim 2, wherein: the bellows-shaped expandable portion (34A) is designed to be shortened when the bellows-shaped expandable portion (34A) is accommodated in the cover member (40); the bellows-shaped expandable portion (34A) is designed to elongate and expand to a predetermined outer diameter when the belt support air cushion (42) inflates and unfolds; and the bellows-shaped expandable portion (34A) is designed to further extend and contract to a predetermined inner diameter as the belt support air cushion (42) moves toward the front of the vehicle. [4] A vehicle occupant restraint device according to claim 3, wherein the expandable portion (34A) of the gas supply pipe (34) is provided with a stent member (36) that limits excessive expansion. [5] The vehicle occupant restraint device according to claim 2, wherein the expandable portion (34A) of the gas supply pipe (34) is formed in a crushed shape along the shoulder belt (22A) when the expandable portion (34A) is housed in the cover member (40). [6] A vehicle occupant restraint device according to any one of claims 2 to 5, wherein the shoulder belt (22A) is movably inserted by a guide member accommodated in the cover member (40) and is not in contact with the expandable portion (34A) of the gas supply pipe (34). [7] Vehicle occupant restraint device according to one of claims 2 to 5, wherein a force limiting mechanism is provided in a retractor (28) which winds the safety belt (22), and the expandable portion (34A) of the gas supply pipe (34) is designed to extend under a load less than a force limiting load of the force limiting mechanism. [8] Vehicle occupant restraint device according to claim 7, wherein the gas generator (32) together with the retractor (28) is embedded in a seat back (16) of the vehicle seat (12). [9] A vehicle occupant restraint device according to claim 1, wherein: a bellows-shaped expandable portion (34A) is provided in the predetermined region of the gas supply pipe (34); and the expandable portion (34A) is provided between a seat back (16) and the belt support air cushion (42).

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