Occupant protection devices

Abstract

To provide an occupant protection device which can suppress occurrence of abnormal noise from a fixation part between an inflator and a seat frame during travel.SOLUTION: An occupant protection device S for protecting an occupant MP seated on a seat 1 has: a seat belt 7; an air bag 25 which is arranged in a region of a lap belt 10, which arrests a lumbar part of the occupant when wearing, in the seat belt 7, and so inflates as to be capable of protecting an upper body MU of the occupant MP; and an inflator 17 capable of supplying an inflation gas to the air bag 25. The inflator 17 is fastened and fixed to a seat frame 4 via a bolt 68 extended from the inflator 17 side in the state that a buffer member 80 comprising a non-metal elastomer is interposed.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an occupant protection device for protecting an occupant seated in a seat. [Background technology]

[0002] Conventionally, there has been a passenger protection device that includes an airbag disposed in the area of ​​the lap belt that restrains the waist of the passenger when the seat belt is fastened (see, for example, Patent Document 1). In this passenger protection device, the airbag inflates from the lap belt toward the front and upper side when deployed, and protects the upper body of the passenger when the inflation is completed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-66425 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the occupant protection device described in Patent Document 1, the inflator body that generates the inflation gas is attached and fixed to the seat frame. However, because the outer tube member of the inflator and the seat frame are both made of metal, there is a concern that they may come into contact with each other due to vibrations while driving, generating abnormal noise.

[0005] The present invention is devised to solve such problems, and has an object to provide an occupant protection device that is capable of suppressing the generation of abnormal noise from the fixing portion between the inflator and the seat frame while driving. [Means for solving the problem]

[0006] The present invention relates to an occupant protection device for protecting an occupant seated in a seat, The seat belt includes an airbag that is disposed in a region of a lap belt that restrains a waist of the occupant when the seat belt is fastened, the airbag inflates to protect the upper body of the occupant, and an inflator that supplies inflation gas to the airbag. The inflator is characterized in that it is fastened to a seat frame supporting the seat via a bolt extending from the inflator side, with a cushioning member made of a non-metallic elastic material interposed therebetween.

[0007] According to the occupant protection device of the present invention, when the inflator is fastened and fixed to the seat frame, the cushioning member adheres closely to the inflator to suppress vibration of the inflator, and the cushioning member prevents metal-to-metal contact between the inflator and the seat frame, thereby suppressing the generation of abnormal noise from the fixed portion between the inflator and the seat frame while driving.

[0008] In the present invention, the inflator body that generates the inflation gas may be configured in a columnar shape and fixed along the seat frame extending in the left-right direction at the lower part of the backrest portion of the seat. In the passenger protection device thus configured, the inflator body can be arranged compactly around the seat by utilizing the space below the backrest of the seat. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view of a seat equipped with an occupant protection device according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a side view of the seat of FIG. [Diagram 3] FIG. 2 is a front view of the seat of FIG. 1, showing the seat belt fastened. [Figure 4] FIG. 4 is a perspective view showing a state in which the inflator is attached to a seat frame. [Diagram 5]FIG. 1A is a diagram showing the fixing portion between the inflator and the seat frame together with the surrounding area, and FIG. 1B is a diagram showing the same fixing portion in isolation. [Figure 6] 2 is a schematic perspective view showing a state in which an airbag used in the occupant protection device of FIG. 1 is inflated by itself. FIG. [Figure 7] FIG. 7 is a schematic vertical cross-sectional view of the airbag of FIG. 6. [Figure 8] FIG. 7 is a plan view showing a base fabric constituting the airbag of FIG. 6. [Figure 9] 1 is a front view of a seat in a state where an airbag has completed inflation in an occupant protection device according to an embodiment; [Figure 10] 1 is a side view of a seat in a state where an airbag has completed inflation in the occupant protection device according to an embodiment. [Figure 11] 1 is a side view showing a state in which an occupant is restrained by an airbag that has completed inflation in the occupant protection device according to the embodiment; [Figure 12] 13 is a diagram showing a modified example in which a pipe portion of an inflator is fixed to a seat frame using a fixing member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of the present invention will be described below with reference to the drawings. As shown in Figs. 1 to 3, an occupant protection device S of the embodiment is mounted on a vehicle seat 1 and includes a seat belt 7, an airbag 25, and an inflator 17. The seat 1 includes a backrest 2 and a seat portion 3.

[0011] The seat belt 7 is configured to include a belt body 8 for restraining an occupant MP seated on the seat 1, a tongue plate 12 attached to the belt body 8, and a buckle 13 for connecting the tongue plate 12. One end of the belt body 8 is fastened to a winding shaft of a retractor (not shown) arranged in the backrest 2, and the other end is fastened to an anchor member 14 (see Figs. 1 and 2) arranged to the left of the rear end 3b of the seat part 3 of the seat 1. In detail, the belt body 8 is arranged so as to be exposed to the outside from the upper left edge side of the backrest 2, and in the case of the embodiment, when the occupant is not seated, the lap belt 10 for disposing the airbag 25 is exposed to the front surface of the backrest 2 as shown in Figs. 1 and 2. The belt body 8 has a lap belt 10 and a shoulder belt 9 stored in the backrest 2, and when an occupant is seated, the lap belt 10, which is disposed substantially along the left-right direction between the anchor member 14 and the buckle 13, restrains the lower body MD (waist) of the occupant MP, and the shoulder belt 9, which extends from the upper left edge side of the backrest 2 and is disposed obliquely to the buckle 13, restrains the upper body MU (head MH and from the shoulders to the chest MB) of the occupant MP (see FIG. 3). Note that in the seat belt 7, a retractor (not shown) disposed in the backrest 2 has a pretensioner mechanism.

[0012] The inflator 17 supplies inflation gas to the airbag 25. In this embodiment, the inflator 17 includes an inflator body 18 that generates inflation gas, and a pipe portion 19 that extends from the inflator body 18 and guides the inflation gas into the airbag 25. The inflator 17 in this embodiment is set to start operating later than the pretensioner mechanism of the seatbelt 7 in order to regulate the withdrawal of the belt body 8 of the seatbelt 7 accompanying the inflation of the airbag 25. Specifically, the inflator 17 is set to operate 5 ms after the operation of the pretensioner mechanism of the seatbelt 7.

[0013] The inflator 17 is attached to a seat frame 4 that supports the seat 1 (more specifically, the seat portion 3) at a position lower than the seat surface 3a of the seat 1. For example, even if the seat 1 is slid significantly back and forth or rotated, the inflator 17 can move together with the seat 1.

[0014] 4 and 5A show a state in which the inflator 17 is attached to the seat frame 4. As shown in these drawings, the inflator body 18 is a generally cylindrical cylinder type, and is provided on the rear side below the seat portion 3 with its axial direction generally aligned in the left-right direction. In this state, a gas discharge port 61 provided on one end side of the inflator body 18 in the axial direction faces leftward of the seat 1.

[0015] The inflator body 18 is fixed to the seat frame 4 at two axially spaced locations using fixing members 65. As the fixing member 65, a bolted clamp including a diameter-reducible ring-shaped clamp 66 and a bolt 68 protruding radially outward from the outer circumferential surface of the clamp 66 is used.

[0016] The clamp 66 is made of sheet metal, and is firmly wrapped around the inflator body 18 by contracting in diameter and deforming while attached to the outer circumferential surface of the inflator body 18. In this way, the fixing member 65 including the clamp 66 is attached to the inflator body 18.

[0017] On the other hand, the mounting plate 70 of the seat frame 4 to which the inflator body 18 is fixed has a flat first mounting surface 71 extending in the left-right direction, and through mounting holes 72 are drilled in the first mounting surface 71 at intervals in the left-right direction (see A in Fig. 5). In this embodiment, as shown in the partially enlarged view of A in Fig. 5, with a shock-absorbing member 80 (described later) interposed therebetween, the inflator body 18 is fastened and fixed to the mounting plate 70 of the seat frame 4 by inserting the bolt 68 of the fixing member 65 into the mounting hole 72 and screwing a nut 75 into the male threaded portion of the bolt 68 from the tip side of the bolt 68 so as to sandwich the mounting plate 70.

[0018] Here, as shown in FIG. 5B, the cushioning member 80 is an annular member in plan view having a through hole 81 at the center, and two opposing flat surfaces 82a, 82b on the mounting surface 71 of the seat frame 4 and the inflator body 18 are provided at a distance in the thickness direction. The material of the cushioning member 80 is a nonmetallic elastic material that exerts a restoring force when fastened in the thickness direction, and specifically, any of elastic materials composed of natural rubber, synthetic rubber, synthetic resin, felt, cloth, etc. can be used. Also, a composite elastic material containing two or more of these can be used. Then, when the inflator body 18 is fastened and fixed, the cushioning member 80 adheres closely to the mounting surface 71 of the seat frame 4 and the inflator body 18 side member (clamp 66 in this example), suppressing vibration of the inflator body 18 and preventing contact between the inflator body 18 side member and the seat frame 4, thereby suppressing the generation of abnormal noise caused by contact between them due to vibration during driving.

[0019] The pipe portion 19 is a metal tube bent into a substantially L-shape, and one end 19a of the pipe portion 19 is connected to the gas discharge port 61 of the inflator body 18, as shown in A of Fig. 5. The end 19a connected to the gas discharge port 61 is made to be an enlarged diameter portion, and is crimped while fitted onto the gas discharge port 61 of the inflator body 18 to form a crimped joint 76. At the crimped joint 76, a part of the pipe portion 19 is fitted into a recessed groove 62 formed at the base of the gas discharge port 61, so that the end 19a of the pipe portion 19 is connected to the inflator body 18.

[0020] 4, the pipe section 19 connected to the inflator main body 18 extends at its end 19a in the horizontal direction, and then changes its orientation to an upper-front direction at a bent section 19b. After that, the pipe section 19 extends in the upper-front direction at a position close to the seat frame 4 on the outside of the seat frame 4, and its tip 19c is disposed at a position slightly lower than the seat surface 3a on the left side of the seat 1. In this embodiment, the tip 19c is configured to be connected to a conduit section 40 of the airbag 25, which will be described later, by using a clamp 20.

[0021] The airbag 25 is folded into a long shape and arranged in the area of ​​the lap belt 10 so as to be overlapped on the upper surface side of the lap belt 10 when the seat belt 7 is worn (see FIG. 3). That is, in the unworn state as shown in FIG. 1, the airbag 25 is arranged on the rear side (the backrest 2 side) of the lap belt 10. In the case of the embodiment, the airbag 25 and the lap belt 10 are covered and integrated with each other by a cover 22 that can be broken when the airbag 25 is deployed and inflated, as shown in FIG. That is, in the embodiment, the gap between the lap belt 10 and the cover 22 forms a storage portion for storing the airbag 25.

[0022] As shown in Figures 6 and 7, the airbag 25 comprises a bag body 26, a conduit portion 40 connected to the inflator 17 to allow inflation gas to flow into the bag body 26, and a belt attachment portion 47 through which the lap belt 10 is inserted.

[0023] The bag body 26 has an outer shape at the time of completion of inflation that is a substantially triangular prism with the axial direction substantially aligned with the left-right direction. More specifically, the bag body 26 is configured so that the shape at the time of completion of inflation when viewed from the left and right sides is a substantially right-angled triangle with a hypotenuse at the front, and the shape at the time of completion of inflation when viewed from the front-rear direction is a substantially rectangular shape that is wider in the vertical direction (see Figs. 9 and 10). The bag body 26 includes a front wall portion 27 disposed at the front side away from the occupant MP at the time of completion of inflation, a rear upper wall portion 28 and a rear lower wall portion 29 disposed on the occupant MP side at the time of completion of inflation, and a left wall portion 30 and a right wall portion 31 disposed opposite each other in the left-right direction at the time of completion of inflation. The bag body 26 has a communication hole 33 that communicates with the conduit portion 40 on the lower surface side of the rear end 29a of the rear lower wall portion 29, and is connected to the conduit portion 40 at the peripheral portion of the communication hole 33. In the case of the embodiment, the communication holes 33 are circularly opened and arranged side by side in two on the left and right sides so as to be substantially symmetrical on both sides of the left and right center of the bag body 26. In addition, vent holes 34, 34 for discharging excess inflation gas are formed near the upper and lower centers on both left and right edge sides of the front wall portion 27. In the bag body 26 of the embodiment, the rear lower wall portion 29 forms a leg contact surface 36 that can contact the upper surface of the legs (thighs) of the occupant MP when inflation is complete, and the rear upper wall portion 28 forms an upper body restraint surface 37 that is disposed in front of the occupant MP when inflation is complete and can restrain the occupant MP from the chest to the head. In the case of the embodiment, the rear upper wall portion 28 and the rear lower wall portion 29 are configured such that the outer shape of the bag body 26 in the fully inflated state is substantially rectangular with the longitudinal direction substantially aligned along the front-rear direction side or the vertical direction side, respectively, and the width dimensions of the longitudinal side are made equal as shown in FIG. The rear upper wall portion 28 is configured so that an upper end 28a is positioned in front of the head MH of the occupant when the bag body is fully inflated (see FIG. 10). The rear upper wall portion 28 and the rear lower wall portion 29 are configured to be disposed so as to be substantially perpendicular to each other in the cross-sectional shape of the bag body 26 when it is fully inflated (see FIG. 7).

[0024] The conduit 40 is connected to the pipe 19 of the inflator 17, and is configured such that the tip 40b side connected to the bag body 26 is closed and the base 40a side is open so as to be connectable to the pipe 19, and is configured to be arranged in the left-right direction so as to be substantially aligned with the lap belt 10 when the airbag 25 is fully inflated. As shown in FIG. 6, the region on the tip 40b side of the conduit 40 is arranged on the lower surface side of the bag body 26 when the airbag 25 is fully inflated, and the region on the tip 40b side is made wider to serve as a gas storage section 41 for temporarily storing the inflation gas that has flowed inside. The base 40a side of the conduit 40 is connected to the pipe 19 of the inflator 17 by using the clamp 20 as described above. The width of the gas storage section 41 is set to be approximately twice the width of the portion of the conduit 40 on the base 40a side. The gas storage section 41 is configured such that the width dimension in the left-right direction is substantially the same as the width dimension in the left-right direction of a portion of the bag body 26 at the rear lower edge (near the portion where the communication hole 33 is disposed) (see Figs. 6 and 8). The gas storage section 41 is formed with an opening 41a corresponding to the communication hole 33 formed in the bag body 26. In the embodiment, the conduit section 40 is formed in a cylindrical shape by joining the peripheries of an upper wall section 43 and a lower wall section 44, which have the same outer shape, and the opening 41a is formed in the region of the upper wall section 43. The opening 41a is joined (sewn) to the periphery of the communication hole 33 around the entire periphery.

[0025] The belt attachment portion 47 is disposed on the lower surface side (lower wall portion 44 side) of the gas storage portion 41 area of ​​the conduit portion 40, and is sewn to the lower wall portion 44 in a generally cylindrical shape with both ends open so that the lap belt 10 can be inserted therethrough (see Figs. 6 and 7). The length of the belt attachment portion 47 is set to be slightly smaller than the width of the gas storage portion 41 in the left and right directions. In other words, the length of the belt attachment portion 47 in the direction along the lap belt 10 is set to be large so that the bag body 26 does not rise excessively from the lap belt 10 when deployed and inflated.

[0026] 7 and 8, the airbag 25 of this embodiment is formed by joining the peripheral edges of a base fabric of a predetermined shape, and in this embodiment, as shown in Figures 7 and 8, is composed of two occupant-side panels 50 and a front panel 55 constituting the bag body 26, two conduit panels 57 and 58 constituting the conduit 40, and a belt attachment panel 60 constituting the belt attachment section 47. The occupant-side panel 50, the front panel 55, the conduit panels 57 and 58, and the belt attachment panel 60 are each formed from flexible woven fabric made of polyester yarn, polyamide yarn, or the like.

[0027] In the embodiment of the occupant protection device S, when the inflator 17 is activated while the device is mounted in the vehicle, the inflation gas discharged from the inflator 17 flows into the bag body 26 via the conduit portion 40, and the bag body 26 protrudes upward and forward from the lap belt 10, breaking the cover 22, and completes inflation as shown in Figures 9 and 10.

[0028] In the occupant protection device S of the embodiment, the airbag 25 (bag body 26) is shaped like a substantially triangular prism with its axial direction aligned substantially along the left-right direction when fully inflated, and is disposed in front of the upper body MU of the occupant MP with the leg contact surface 36 in contact with the upper surface of the leg MT. Therefore, even if the occupant MP significantly moves the upper body MU closer to the lower body MD when the airbag 25 is fully inflated, the leg contact surface 36 is supported by the leg MT over a wide area as shown in Fig. 11, so that the upper body MU of the occupant MP (from the chest MB to the head MH) is restrained from collapsing or being compressed, and the upper body MU of the occupant MP (from the chest MB to the head MH) can be appropriately restrained by the upper body restraining surface 37 disposed in front of the upper body MU so as to face it. Furthermore, in the embodiment of the occupant protection device S, the fully inflated shape of the airbag 25 (bag main body 26) is approximately triangular prism-shaped, so that even when the occupant MP is seated in a seat with the backrest inclined, the upper body MU can be appropriately restrained by the upper body restraint surface 37.

[0029] According to the embodiment of the occupant protection device S configured as described above, when the inflator body 18 constituting the inflator 17 is fastened and fixed to the seat frame 4, the cushioning member 80 comes into close contact with the inflator body 18 to suppress vibration of the inflator body 18, and the cushioning member 80 prevents metal-to-metal contact between the inflator body 18 side members and the seat frame 4, thereby suppressing the generation of abnormal noise from the fixed portion between the inflator body 18 and the seat frame 4 during driving.

[0030] In addition, in the occupant protection device S of this embodiment, the inflator body 18 that generates the inflation gas is configured in a columnar shape and is fixed along the seat frame 4 extending in the left-right direction at the bottom of the backrest portion 2 of the seat 1, so that the inflator body 18 can be compactly arranged around the seat 1 by utilizing the space below the backrest portion 2 of the seat 1.

[0031] Next, a modified example of this embodiment will be described. Fig. 12 shows an example in which pipe portion 19, which extends long between inflator body 18 and conduit portion 40, is fastened and fixed to seat frame 4 with a shock-absorbing member interposed therebetween. In this example, pipe portion 19 is fixed to seat frame 4 by using fixing members 65B at two points spaced apart in the longitudinal direction of pipe portion 19.

[0032] The fixing member 65B is a bolted clamp having a ring-shaped clamp 66 that can be contracted and a bolt 68 that protrudes radially outward from the outer circumferential surface of the clamp 66, similar to the fixing member 65 described above. As shown in the partially enlarged view in B of FIG. 12, a through-hole mounting hole 72B is drilled in the mounting plate portion 70 of the seat frame 4 to which the pipe portion 19 is fixed, and the bolt 68 of the fixing member 65B is inserted into this mounting hole 72B, and a nut 75 is screwed into the male thread portion of the bolt 68 from the tip side of the bolt 68, thereby fixing the pipe portion 19 to the mounting plate portion 70 of the seat frame 4. However, since a gap is generated between the clamp 66 wrapped around the pipe portion 19 and the mounting surface 71 on the seat frame 4 side, a sleeve 78 having a height corresponding to this gap is inserted onto the bolt 68, and the mounting plate portion 70 is sandwiched between the nut 75 and the sleeve 78. In this case, if the sleeve 78 is made of a non-metallic elastic material, the sleeve 78 will function as a buffer member, and will come into close contact with the pipe portion 19 to suppress vibration of the pipe portion 19, while also avoiding metal-to-metal contact between the pipe portion 19 and the seat frame 4, thereby suppressing the generation of abnormal noise during driving from the fixed portion between the pipe portion 19 and the seat frame 4. The above has been explained using the fixed portion on the base end side of the pipe portion 19 (the side closer to the inflator main body 18) as an example, but a similar abnormal noise prevention effect can also be obtained in the fixed portion at the tip side of the pipe portion 19 that is fixed to the second mounting surface 73 of the seat frame 4 using the fixing member 65B.

[0033] Although the embodiment of the present invention has been described in detail above, this is merely an example. For example, in the above embodiment, a bolt clamp is used as the fixing member, but in some cases, a bolt implanted in the outer cylinder of the inflator body can be used as the fixing member instead of the bolt clamp. The present invention can be embodied in various modified forms without departing from the spirit of the invention. [Explanation of symbols]

[0034] 1...seat, 2...backrest, 4...seat frame, 7...seat belt, 10...lap belt, 17...inflator, 18...inflator body, 19...pipe, 25...airbag, 65,65B...fixing member (clamp with bolt), 68...bolt, 78,80...cushioning member, MP...occupant, S...occupant protection device, MU...upper body.

Claims

1. An occupant protection device for protecting an occupant seated in a seat, Seat belt and an airbag disposed in a region of a lap belt that restrains a waist of the occupant when the seat belt is fastened, the airbag inflating to protect an upper body of the occupant; an inflator capable of supplying inflation gas to the airbag; The configuration has The inflator is fastened to a seat frame supporting the seat via a bolt extending from the inflator with a buffer member made of a nonmetallic elastic material interposed therebetween, the cushioning member has two flat surfaces that are spaced apart in the thickness direction and that face the mounting surface of the seat frame and the inflator, respectively, and when the inflator is fastened and fixed, one flat surface is in close contact with the mounting surface of the seat frame and the other flat surface is in close contact with a member on the inflator side.

2. An occupant protection device for protecting an occupant seated in a seat, Seat belt and an airbag disposed in a region of a lap belt that restrains a waist of the occupant when the seat belt is fastened, the airbag inflating to protect an upper body of the occupant; an inflator capable of supplying inflation gas to the airbag; The configuration has The inflator is fastened to a seat frame supporting the seat via a bolt extending from the inflator with a buffer member made of a nonmetallic elastic material interposed therebetween, The buffer member has a through hole through which the bolt passes, an occupant protection device characterized in that a bolt provided on a fixing member attached to the outer peripheral surface of the inflator is inserted into a through hole of the buffer member and an attachment hole formed on the side of the seat frame, and the buffer member is disposed between the fixing member and the seat frame.

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