JP7635737B2 - Occupant protection devices - Google Patents

Description

The present invention relates to an occupant protection device for protecting an occupant seated in a seat.

Conventionally, passenger protection devices have been configured with an airbag that is placed in the area of the lap belt that restrains the passenger's waist when the seat belt is fastened (see, for example, Patent Document 1). In this passenger protection device, the airbag is inflated upward and forward from the lap belt as inflation gas is generated, and when inflation is complete, the upper half of the passenger's body is protected.

JP 2020-66425 A

In the above-mentioned passenger protection device, the pipe section that guides the inflation gas into the airbag and the conduit section on the airbag side are connected and fixed using a fastening member such as a clamp, and the position of the conduit section at the connection with the pipe section determines the deployment and inflation position of the airbag body. However, if the position of the conduit section shifts in the direction of the propulsive force caused by the gas pressure when inflation gas is generated, this may affect the deployment and inflation position of the airbag body.

The present invention aims to solve these problems and provide an occupant protection device that can prevent the conduit section from shifting out of position at the connection with the pipe section when inflation gas is generated.

The occupant protection device according to the present invention is an occupant protection device for protecting an occupant seated in a seat, comprising a seat belt, an airbag that is disposed in an area of a lap belt of the seat belt that restrains the waist of the occupant when the seat belt is worn and that inflates to protect the upper body of the occupant, an inflator body that generates inflation gas, and a pipe portion that extends from the inflator body and guides the inflation gas into the airbag,
the airbag has a conduit portion extending toward a side surface of the seat and connected to the pipe portion to allow inflation gas to flow into the bag body ,
The conduit portion comprises a cylindrical conduit main body that fits into the tip of the pipe portion from the outside and is fastened and fixed to the tip of the pipe portion by a clamp serving as a fastening member , and an extension piece that extends outward from the conduit main body, and the extension piece is fixed to a seat frame that supports the seat.

According to the passenger protection device of the present invention, even if a propulsive force due to the gas pressure of the inflation gas acts on the conduit, a reaction force in the opposite direction acts on the conduit via the extension piece fixed to the seat frame, so the movement of the conduit is restricted. This makes it possible to suppress the positional deviation of the conduit at the connection with the pipe when inflation gas is generated.

Here, the extension pieces can be configured to be provided on both sides of the flow path of the inflation gas in the conduit body. In this way, it is possible to more effectively prevent the conduit from shifting out of position.

1 is a perspective view of a seat equipped with an occupant protection device according to an embodiment of the present invention; FIG. 2 is a side view of the seat of FIG. 1 . FIG. 2 is a front view of the seat of FIG. 1 with the seat belt fastened; FIG. 1A is a diagram showing the connection between the pipe portion and the conduit portion together with its surroundings, and FIG. 1B is a diagram showing the connection between the pipe portion and the inflator main body together with its surroundings. 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. FIG. 6 is a schematic vertical cross-sectional view of the airbag of FIG. 5 . FIG. 6 is a plan view showing a base fabric constituting the airbag of FIG. 5 . 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; 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; 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; FIG. 13 is a diagram of a modified example in which a plurality of extension pieces are provided.

One embodiment of the present invention will now be described with reference to the drawings. As shown in Figures 1 to 3, the occupant protection device S of this embodiment is mounted on a vehicle seat 1 and is configured to include a seat belt 7, an airbag 25, and an inflator 17. The seat 1 includes a backrest 2 and a seat portion 3.

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) disposed in the backrest 2, and the other end is fastened to an anchor member 14 (see Figs. 1 and 2) disposed to the left of the rear end 3b of the seat part 3 of the seat 1. In detail, the belt body 8 is disposed so as to be exposed to the outside from the upper left edge side of the backrest 2. In the embodiment, when the occupant is not seated, the lap belt 10 for positioning 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. When the occupant is seated, the lap belt 10, which is arranged so as to extend substantially along the left-right direction between the anchor member 14 and the buckle 13, restrains the lower body MD (lumbar region) of the occupant MP, and the shoulder belt 9, which extends from the upper left edge of the backrest 2 and is arranged diagonally to the buckle 13, restrains the upper body MU (shoulders to chest MB and head MH) of the occupant MP (see FIG. 3). In addition, in the seat belt 7, a retractor (not shown) arranged in the backrest 2 has a pretensioner mechanism.

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. In this embodiment, the inflator 17 is set to start operating later than the pretensioner mechanism of the seat belt 7 in order to regulate the pulling out of the belt body 8 of the seat belt 7 accompanying the inflation of the airbag 25. Specifically, the inflator 17 is set to start operating 5 ms after the pretensioner mechanism of the seat belt 7 is activated.

The inflator 17 is attached to the 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, and the inflator 17 can move together with the seat 1, even if the seat 1 is slid significantly back and forth or rotated, for example.

As shown in FIG. 4, the inflator body 18 is a generally cylindrical cylinder type, and is provided on the rear side below the seat 3 with its axial direction generally aligned with the left-right direction. At this time, the gas discharge port 61 provided on one end of the inflator body 18 in the axial direction faces the left direction of the seat 1.

As shown in FIG. 4B, the inflator body 18 is fixed to the seat frame 4 at two axially spaced locations using fixing members 65. The fixing members 65 are bolted clamps that include a ring-shaped clamp 66 that can be contracted and a bolt 68 that protrudes radially outward from the outer periphery of the clamp 66.

The clamp 66 is made of sheet metal and is firmly wrapped around the inflator body 18 by shrinking in diameter while attached to the outer circumferential surface of the inflator body 18. This attaches the fixing member 65 including the clamp 66 to the inflator body 18.

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 has through mounting holes 72 spaced apart in the left-right direction (see B in FIG. 4). In this embodiment, the bolt 68 of the fixing member 65 is inserted into this mounting hole 72, and a nut 75 is screwed onto the male thread of the bolt 68 from the tip side of the bolt 68 so as to sandwich the mounting plate 70, thereby fixing the inflator body 18 to the mounting plate 70 of the seat frame 4.

The pipe section 19 is a metal tube bent into a roughly L-shape, with one end 19a connected to the gas discharge port 61 of the inflator body 18 (see B in FIG. 4). The end 19a connected to the gas discharge port 61 is an enlarged diameter section, which is crimped while fitted onto the gas discharge port 61 of the inflator body 18 to form a crimp joint 76. At the crimp joint 76, a portion of the pipe section 19 fits into an annular groove 62 formed at the base of the gas discharge port 61, thereby connecting the end 19a of the pipe section 19 to the inflator body 18.

The pipe section 19 connected to the inflator body 18 extends horizontally at its end 19a, and then bends upward and forward at its bend 19b, as shown in FIG. 4A. A tip 19c is disposed at the end of the pipe section 19, which extends upward and forward, close to the seat frame 4. This tip 19c is configured to be connected to a conduit section 40 (described later) in the airbag 25 using a clamp 20.

The airbag 25 is folded into a long shape and placed in the area of the lap belt 10 so as to overlap the upper surface 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 placed on the rear side (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. 3. That is, in the embodiment, the gap between the lap belt 10 and the cover 22 constitutes a storage area for storing the airbag 25.

As shown in Figures 5 and 6, the airbag 25 includes a bag body 26, a conduit 40 that is connected to the inflator 17 and allows inflation gas to flow into the bag body 26, and a belt attachment 47 through which the lap belt 10 is inserted.

The bag body 26 has an outer shape when fully inflated, which is a substantially triangular prism with the axial direction generally aligned with the left-right direction. In detail, the bag body 26 is configured so that the fully inflated shape when viewed from the left and right sides is a substantially right-angled triangle with a hypotenuse at the front, and the fully inflated shape when viewed from the front-rear direction is a substantially rectangular shape with a wide top-bottom width (see Figures 8 and 9). The bag body 26 includes a front wall portion 27 disposed at the front side away from the occupant MP when fully inflated, a rear upper wall portion 28 and a rear lower wall portion 29 disposed on the occupant MP side when fully inflated, and a left wall portion 30 and a right wall portion 31 disposed opposite each other on the left-right side when fully inflated. The bag body 26 has a communication hole 33 on the underside of the rear end 29a of the rear lower wall portion 29 that communicates with the conduit portion 40, and is connected to the conduit portion 40 at the peripheral portion of this communication hole 33. In 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 surfaces 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 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 when inflation is complete 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 the same as shown in FIG. 6. The rear upper wall portion 28 is configured so that the upper end 28a is positioned in front of the head MH of the occupant when the bag body is fully inflated (see FIG. 9). The rear upper wall portion 28 and the rear lower wall portion 29 are configured to be positioned 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. 6).

The conduit 40 includes a cylindrical conduit body 41 that is connected to the pipe 19 of the inflator 17, and an extension piece 80 that extends outward from the conduit body 41 (see FIG. 4A and FIG. 7 for the extension piece 80). The conduit body 41 is configured such that the tip 41b side that is connected to the bag body 26 is closed and the base 41a side is open so that it can be connected to the pipe 19, and is configured to be arranged in the left-right direction so as to be approximately aligned with the lap belt 10 when the airbag 25 is fully inflated. As shown in FIG. 5, the region on the tip 41b side of the conduit body 41 is arranged on the underside of the bag body 26 when inflation is complete, and the region on the tip 41b side is made wide to serve as a gas storage section 42 that temporarily stores the inflation gas that has flowed inside.

The width of the gas storage section 42 is set to about twice the width of the base section 41a of the conduit main body 41. The width of the gas storage section 42 on the left-right side is configured to be approximately the same as the width of the rear lower edge side of the bag body 26 (near the location of the communication hole 33) (see Figures 5 and 7). The gas storage section 42 has an opening 42a corresponding to the communication hole 33 formed in the bag body 26. In the embodiment, the conduit main body 41 is made cylindrical by joining the peripheries of the upper wall section 43 and the lower wall section 44, which have the same external shape, and the opening 42a is formed in the area of the upper wall section 43. The opening 42a is joined (sewn) to the periphery of the communication hole 33 all around.

As shown in A of FIG. 4, an extension piece 80 is provided on the base 41a side of the conduit main body 41, extending outward from the conduit main body 41. As shown in FIG. 7, the extension piece 80 is formed by connecting together portions 80a and 80b corresponding to the extension piece 80 provided on the two conduit panels 57, 58 that constitute the conduit 40. The extension piece 80 is generally triangular in plan view, and an insertion hole 82 for inserting a fixing screw member 85 is formed near a corner portion spaced from the conduit main body 41.

4A, the connection between the conduit 40 and the pipe 19 of the airbag 25 will be described. The tip 19c of the pipe 19 is an annular protrusion that protrudes radially outward. In this embodiment, the tip 19c is inserted into the cylindrical conduit body 41, and the clamp 20 as a fastening member is reduced in diameter from the outside of the conduit body 41, so that the conduit 40 (more specifically, the conduit body 41) is connected and fixed to the pipe 19. An extension piece 80 is provided on the base 41a side of the conduit body 41 connected to the pipe 19, near the location of the clamp 20. As shown in the partially enlarged view in A of FIG. 4, a fixing screw member 85 is inserted into the insertion hole 82 of the extension piece 80, and the screw portion is screwed into the second mounting surface 73 of the mounting plate portion 70 of the seat frame 4 facing the extension piece 80, thereby fixing the extension piece 80 to the mounting plate portion 70 of the seat frame 4. At the connection portion between the conduit portion 40 and the pipe portion 19, the clamp 20, the tip 19c of the pipe portion 19, and the fixing insertion hole 82 of the extension piece 80 are arranged in this order toward the outflow direction of the inflation gas (upper left direction in A of FIG. 4). In this embodiment, the movement of the conduit portion 40 at the connection portion with the pipe portion 19 is restricted by the extension piece 80 fixed to the seat frame 4, so that the positional deviation of the conduit portion 40 at the connection portion when the inflation gas is generated can be suppressed compared to an occupant protection device that does not virtually have the extension piece 80.

The belt attachment portion 47 is disposed on the underside (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 (see Figs. 5 and 6). The length of the belt attachment portion 47 is set to be slightly smaller than the width of the gas storage portion 41 on the left and right sides. In other words, the length of the belt attachment portion 47 is set to be larger on the side along the lap belt 10 so that the bag body 26 does not rise excessively from the lap belt 10 when deployed and inflated.

The airbag 25 of this embodiment is formed by joining the periphery of a base fabric of a predetermined shape, and as shown in Figures 6 and 7, is composed of two occupant-side panels 50 and a front panel 55 that constitute the bag body 26, two conduit panels 57 and 58 that constitute the conduit 40, and a belt attachment panel 60 that constitutes 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.

The occupant-side panel 50 is disposed on the occupant MP side when inflation is complete and constitutes the area from the leg contact surface 36 to the upper body restraint surface 37, and mainly constitutes the area from the rear upper wall portion 28 to the rear lower wall portion 29 in the bag body 26 when inflation is complete. Specifically, the occupant-side panel 50 has a lower portion 52 that mainly constitutes the leg contact surface 36 (rear lower wall portion 29), and an upper portion 51 that mainly constitutes the upper body restraint surface (rear upper wall portion 28). In detail, the lower portion 52 constitutes the rear lower wall portion 29 and the rear lower area of the left wall portion 30 and the right wall portion 31, and the upper portion 51 constitutes the rear upper wall portion 28 and the rear upper area of the left wall portion 30 and the right wall portion 31, and both have an approximately hexagonal outer shape. The occupant-side panel 50 has an outer shape in which the lower portion 52 and the upper portion 51 are connected on one side, and the lower portion 52 and the upper portion 51 are symmetrical with respect to the connecting portion 50a.

The front panel 55 mainly constitutes the front wall 27 of the bag body 26 when inflation is complete, and more specifically constitutes the front wall 27 and the front areas of the left wall 30 and right wall 31. The front panel 55 has a substantially hexagonal outer shape. Specifically, the outer shape of the front panel 55 is a hexagon that substantially matches the lower and upper parts 52 and 51 (see FIG. 7) of the occupant-side panel 50 in an open state that separates the remaining edges (front edges 51c and 52c) that connect the rear left edges 51a and 52a and the rear right edges 51b and 52b, respectively, located on the left and right sides of the connecting part 50a.

The two conduit panels 57, 58 have the same external shape as shown in FIG. 7, and respectively constitute the upper wall 43 and the lower wall 44 of the conduit 40. The belt attachment panel 60 has a generally rectangular external shape, and is folded in half to join the short-side edges 60a, 60b together to form the belt attachment section 47.

In the passenger protection device S of the embodiment, when the inflator 17 is activated while the device is mounted on the vehicle, the inflation gas discharged from the inflator 17 flows into the bag body 26 through the conduit 40, and the bag body 26 breaks the cover 22 and protrudes forward and upward from the lap belt 10, completing the inflation as shown in Figures 8 and 9. At that time, a propulsive force acts on the conduit 40 of the airbag 25 in the direction shown by the arrow in Figure 9, but the conduit 40 is fixed to the pipe 19 and is fixed to the seat frame 4 via the extension piece 80, and the reaction force from the pipe 19 and the seat frame 4 acts to suppress the movement (displacement) of the conduit 40 at the connection with the pipe 19.

In the occupant protection device S of the embodiment, the airbag 25 (bag body 26) is shaped like a triangular prism with its axial direction aligned generally 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. 10, 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 restraint surface 37 disposed in front of the upper body MU so as to face it. In addition, in the embodiment of the occupant protection device S, the shape of the airbag 25 (bag body 26) when fully inflated is a substantially triangular prism shape, so that the upper body MU can be appropriately restrained by the upper body restraint surface 37 even when the occupant MP is seated in a seat with the backrest inclined.

According to the embodiment of the occupant protection device S configured as described above, even if a propulsive force due to the gas pressure of the inflation gas acts on the conduit portion 40, a reaction force in the opposite direction acts on the conduit portion 40 via the extension piece 80 fixed to the seat frame 4, so the movement of the conduit portion 40 is restricted. This makes it possible to suppress the positional deviation of the conduit portion 40 at the connection portion with the pipe portion 19 when inflation gas is generated.

In the above embodiment, one extension piece 80 is provided to be fixed to the seat frame 4, but the number and position of the extension pieces 80 can be changed as appropriate. For example, as shown in FIG. 11, it is also possible to provide extension pieces 80 on both sides of the flow path of the inflation gas in the conduit main body 41, and to configure each extension piece 80 to be fixed to the mounting plate portion 70 of the seat frame 4. In this way, it is possible to more effectively prevent the conduit portion 40 from shifting in position at the connection portion with the pipe portion 19.

The above describes an embodiment of the present invention in detail, but this is merely one example. The present invention can be implemented in various modified forms without departing from the spirit of the invention.

1...seat, 2...backrest, 4...seat frame, 7...seat belt, 10...lap belt, 18...inflator body, 19...pipe, 19c...tip, 25...airbag, 40...conduit, 41...conduit body, 80...extension, MP...occupant, S...occupant protection device.

Claims (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 body that generates inflation gas;
a pipe portion extending from the inflator body to guide the inflation gas into the airbag;
The configuration has
the airbag has a conduit portion extending toward a side surface of the seat and connected to the pipe portion to allow inflation gas to flow into the bag body ,
The conduit portion comprises a cylindrical conduit main body that fits into the tip of the pipe portion from the outside and is fastened and fixed to the tip of the pipe portion by a clamp as a fastening member , and an extension piece that extends outward from the conduit main body, and the extension piece is fixed to a seat frame that supports the seat, characterized in that the conduit portion comprises a cylindrical conduit main body that fits into the tip of the pipe portion from the outside and is fastened and fixed to the tip of the pipe portion by a clamp that serves as a fastening member, and an extension piece that extends outward from the conduit main body, 2. The occupant protection device according to claim 1, characterized in that, at the connection portion between the conduit portion and the pipe portion, the clamp, the tip of the pipe portion, and an insertion hole for fixing the extension piece are arranged in this order toward the outflow direction of the inflation gas.

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