JP2009035092A - Waist restraining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide structure allowing use of a small inflator such as a micro gas generator (MGG) and contributing to the cost reduction of the whole device. <P>SOLUTION: A waist restraining device of this invention comprises a gas supply means for supplying expansion gas at the time of generation of an impact, an expansion means stored in a lower part of a seat part of a seat (hereafter a seat cushion) in a compressed status for expanding/developing upward by the expansion gas, and a frame member arranged at the lower part of the seat cushion for pushing up the seat cushion by the development of the expansion means and restraining an occupant from moving forward. The frame member is formed in a U shape having an opening part facing to a vehicular front side as a whole and two roundly-bent corners. The frame member moves upward by the development of the expansion means. The frame member absorbs the impact on the occupant by deformation caused by load of the occupant to the front of a vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an occupant restraint device that restrains an occupant's waist when an impact such as a vehicle collision occurs.

When the vehicle collides forward, the occupant tries to move forward due to inertia. When the occupant is wearing the seat belt, the forward movement of the occupant can be suppressed to some extent by the restraining action of the shoulder belt and the waist belt of the seat belt device. In order to make this even more reliable, a waist restraint device that applies technology to limit the forward movement of the occupant by instantly raising the front end of the seat cushion when the vehicle suddenly decelerates due to a forward collision is proposed. Has been. For example, in a waist restraint device disclosed in Patent Document 1 below, a metal bag is inflated and deployed by a gas generated in an inflator. The inflated and deployed metal bag pushes up the front end portion of the seat cushion, thereby restraining the forward movement of the occupant's waist (pelvis).
JP 2005-297580 A

  However, the apparatus disclosed in Patent Document 1 requires an air bag with a large capacity (explosive amount) in order to restrain an occupant with a metal bag itself, which increases the cost. In addition, the large-capacity air bag increases the size of the device itself, and there is a problem in the capacity of accommodation in a limited space below the seat.

  The present invention has been made in view of the above situation, and an object thereof is to provide a structure that enables the use of a small inflator such as a micro gas generator (MGG) and contributes to the cost reduction of the entire apparatus. And

  Another object of the present invention is to provide a structure that contributes to downsizing of the waist restraint device.

  In order to achieve the above object, the present invention provides a waist restraint device for restraining a waist part of an occupant seated on a seat in a vehicle, a gas supply means for supplying an expansion gas when an impact occurs; An inflating means accommodated in a compressed state in the lower part and inflated and expanded upward by the inflating gas; disposed at the lower part of the seat cushion; And a frame member that pushes up and restrains the forward movement of the occupant. And as for the said frame member, the open part as a whole is shape | molded in the U shape which faced the vehicle front side, and the corner | angular part of two places is bent with roundness. The frame member moves upward by the expansion of the expansion means. The frame member is configured to absorb an impact on the occupant by being deformed by a load from the occupant forward of the vehicle.

  Preferably, the frame member has two bent portions (hereinafter referred to as “main bent portions”) forming the U-shape, or at least two other bent portions (hereinafter referred to as “main bent portions”). (Referred to as “sub-bent portion”) on the open side of the main bent portion.

  Moreover, it is preferable that the said frame member has a weak part in which the cross-sectional area of a cross section is smaller than another part in part.

  As the gas supply means, an MGG (micro gas generator) which is a well-known small inflator can be used.

  The frame member is formed in a “U-shape” with the open portion facing the front side of the vehicle, but may be “U-shaped”. The front (vehicle traveling direction) of the frame is open, the opposite side is closed, and the portion corresponding to the closed side receives pressure from the pelvis of the occupant to absorb it.

  As described above, the “U” shape includes a U shape and an arc shape, and basically means a shape in which one end frame is bent to form two end portions. However, it is also possible to adopt a structure in which the side of the open portion of the “U” is a closed rectangle and the closed side is the rotation axis. In this case, the side serving as the rotation axis does not directly absorb the load and pressure from the occupant.

  As described above, in the present invention, the frame member formed in a U-shape is raised by the expansion of the expansion means to restrain the vicinity of the pelvis of the occupant. It is possible to use a small one (for example, one having a small amount of explosives) as the gas supply means for supplying the expansion gas to the expansion means. Further, since the side opposite to the open part of the frame member is configured to be located near the occupant's pelvis, when the part corresponding to the closed side receives pressure from the occupant's pelvis, the frame The member itself is deformed and can absorb an impact.

  In addition, the frame member as a whole is formed in a U-shape with the open part facing the front side of the vehicle, and the corners at the two locations are rounded and bent. When applied, it can be easily deformed and the impact on the passenger can be reduced.

Further, in the frame member, two bent portions (hereinafter referred to as “main bent portions”) forming the U-shape, or at least two or more other bent portions (hereinafter referred to as “secondary bent portions”). If the structure has a "bent portion") on the open side with respect to the main bent portion, the impact relaxation performance is further improved. Similarly, it is possible to improve impact mitigation performance by forming a weakened portion having a cross-sectional area smaller than the other portions in a part of the frame member.

  Hereinafter, the best mode for carrying out the present invention will be described in detail using embodiments. FIG. 1 is a plan view showing a structure of a waist restraint device 21 according to an embodiment of the present invention and an arrangement in a lower part of a vehicle seat (seat cushion omitted). FIG. 2 is a side view showing the structure of the waist restraint device 21 according to the embodiment and the arrangement inside the vehicle seat, and shows a normal state (when the device is not operating). FIG. 3 is a side view showing the structure of the waist restraint device 21 according to the embodiment and the arrangement inside the vehicle seat, and shows a state when the impact is generated (when the device is operating).

  A waist restraint device 21 according to the present embodiment restrains the waist of an occupant M seated on a seat in a vehicle, and an inflator (MGG) 27 as a gas supply means for supplying an inflation gas when an impact occurs; A metal bellows 24 accommodated in a compressed state in a lower portion of the seating portion 17 (hereinafter referred to as “seat cushion”) and inflated and expanded upward by an inflation gas discharged from the inflator 27; A frame member 22 that moves upward by the deployment of the metal bellows 24 and pushes up the seat cushion 17 to restrain the vicinity of the pelvis of the occupant M is provided. Here, the frame member 22 is formed in a U shape with an open portion facing the front side of the vehicle, and a side opposite to the open portion is positioned near the pelvis of the occupant M.

  The metal bellows 24 is formed in a substantially cylindrical shape and is compressed into a bellows shape when housed.

  The frame member 22 has a structure that absorbs an impact to the occupant M by being deformed by a load in front of the vehicle, and can be made of aluminum that is easily plastically deformed, for example. As the frame member 22, for example, an aluminum alloy A2014 formed into a round bar shape with a diameter of 14 mm is used. This is formed into a U-shaped portion having a width of 331 mm and a depth of 160 mm. As the material of the frame member 22, it is most preferable to use magnesium or an alloy thereof in addition to aluminum. It should be noted that other materials can be used as long as they have the same plastic deformation characteristics as these.

  As shown in FIGS. 1 to 3, the seat pan 15 is attached to the right seat frame 12 and the left seat frame 13. The bottom of the seat cushion 17 is supported entirely by the seat pan 15. The waist restraint device 21 according to the present embodiment is disposed on the front side (the vehicle front side) of the seat frames 12 and 13. The left and right seat frames 12 and 13 are a rotary shaft for a height adjuster mechanism (not shown) or a front frame member (front cross member) for adjusting the height of the seat pan 15 up and down in the front, and the rear frame in the rear. It is connected to a member (rear cross member) 14.

  The waist restraint device 21 of this embodiment is disposed in a notch (recessed) portion formed at the front end of the seat pan 15 and operates without interfering with the seat pan 15. Therefore, the notch portion in the seat pan 15 is processed into a size and shape that does not affect the operation of the waist restraint device 21. The waist restraint device 21 is disposed so as to straddle the seat frames 12 and 13 in front of the seat pan 15 and is directly fixed to the upper part or the rear part of the seat frames 12 and 13.

  As shown in FIG. 1, the sheet pan 15 is a plate-like member made of metal and having a predetermined thickness, for example, integrally processed into a concave shape. Further, in order to improve the strength, a plurality of protrusions that are partially concavo-convex are provided, and the seat cushion 17 for seating surface is arranged to cover from below. The seat pan 15 is fixed to the seat frames 12 and 13 with bolts or the like, and the seat cushion 17 for the seating surface is folded into the seat pan 15 by fixing and bending a reinforcing material at an end thereof by sewing or the like. The hook is formed in a shape, and a hook part is sewn in part, and the hook part is hooked and fixed on the seat pan 15 in accordance with the holed portion. The seat cushion 17 for the seat surface fixed to the upper surface of the seat pan 15 is deformed by the weight of the occupant M, and is bent so as to be convex downward, thereby improving the comfort of the occupant (improving the sitting comfort). ing.

  In the waist restraint device 21 according to the present embodiment, the metal bellows 24 is inflated and expanded obliquely upward by the high-pressure gas released from the inflator 27, and the frame member 22 is rotated (swinged) about the rotation shaft 29. Structure. As shown in FIG. 2, the metal bellows 24 is accommodated in the lower portion of the seat cushion 17 in a compact state before being deployed. On the other hand, when the metal bellows 24 is expanded by the operation of the inflator 27, the frame member 22 is raised and the seat cushion 17 rises and restrains the waist (pelvis) of the occupant M as shown in FIG.

  FIG. 4 is an exploded perspective view showing the structure of the waist restraint device 21 according to the embodiment. FIG. 5 is a partial side view showing the structure of the main part of the waist restraint device 21 according to the embodiment.

  In FIG. 4, the lower bracket 25 holds main components (the inflator 27, the metal bellows 24, and the frame member 22), and the lateral sides are fixed to the seat frames 12 and 13 by fixing bolts 34. . In FIG. 4, the left part of the lower bracket 25 is shown in an exploded state, and the right part is shown in an assembled state. A circular concave portion 25 a in which the metal bellows 24 is accommodated is provided at a substantially central portion of the upper surface of the lower bracket 25. A through hole 25b for incorporating the inflator case 26 is formed at the center bottom of the recess 25a. The inflator case 26 holds the inflator 27 and is formed in a substantially cylindrical shape. The inflator case 26 that houses the inflator 27 is screwed into the bottom surface of the metal bellows 24 and is fixed by a cap 28.

  As shown in FIG. 4, a bracket 24 a is fixed to the upper part of the metal bellows 24, and is fixed to the frame member 22 by two fixing bolts 35. The two fixing bolts 35 are screwed into two holes 52 formed substantially at the center of the frame member 22.

  A top plate 23 connected to the metal bellows 24 via the bracket 24a is disposed on the bracket 24a. The top plate 23 is moved upward in conjunction with the deployment of the metal bellows 24. The top plate 23 is shaped so that the outer periphery thereof is generally along the inner surface of the frame member 22 so as to cover the inside of the frame member 22.

  The bracket 24a has side portions extending substantially vertically upward on both the left and right sides, and a hole 56 through which the shaft 36 passes is formed in the side portions. A mounting member 54 having a hole aligned with the hole 56 is provided on the bottom surface of the top plate 23. Then, the top plate 23 is rotatably supported with respect to the bracket 24 a by passing the shaft 36 through a hole formed in the attachment member 54 on the bottom surface of the top plate 23 and a hole 56 formed on the side surface of the bracket 24. is doing. The shaft 36 is secured by a shaft fixing split pin 37.

  The waist restraint device 21 according to the present embodiment further includes a support structure (30, 32, 33, etc.) having functions such as supporting the frame member 22 and restricting the lowering operation of the member 22. These structures will be described in detail later with reference to FIG.

  FIG. 5 shows an enlarged view of the circled portion 100 of FIGS. In FIG. 5, FIG. 2 and FIG. 3, the left and right are reversed. In this example, the rotary shaft 29 provided in front of the frame member 22 is directly assisted and supported. Between the lower bracket 25 that fixes the rotation shaft 29 and the rotation shaft 29, an auxiliary bracket 42 that is configured integrally with the lower bracket 25 is provided. The upper cross-sectional shape of the auxiliary bracket 42 on the frame member 22 side does not interfere with the end portion of the frame member 22a in the undeployed state. On the other hand, the end portion of the frame member 20b at the time of deployment engages (contacts) with the notch portion 42a of the auxiliary bracket 42 and functions as a stopper for the frame member 22. That is, the auxiliary bracket 42 assists and supports the load forward (right side in FIG. 5) by the occupant.

  FIG. 6 is a plan view showing an example of the frame member 22 used in the waist restraint device 21 according to the present invention. As described above, the frame member 22 is formed into a U-shape with the open portion facing the front side of the vehicle as a whole, and the corners are bent with roundness. As the metal bellows 24 is deployed, the frame member 22 moves upward and is deformed by a load from the occupant M forward of the vehicle, thereby absorbing the impact on the occupant M.

  The frame member 22 has two bent portions (hereinafter referred to as “main bent portions”) 22m constituting “U-shape”, or at least two other bent portions (hereinafter referred to as “hereinafter referred to as“ main bent portions ”). It is preferable to provide 22s closer to the open side than the main bent portion 22m. In the example of FIG. 6, in addition to the two main bent portions 22m, four sub-refractive portions 22s are formed. In FIG. 6, 22x is a region that directly receives a load (impact) from the occupant M, and 22y has a role of a lever that rotates (swings) the frame member 22 and also deforms itself to absorb the impact. And so on.

  The sub-bending portion 22s can be bent in the vertical direction in addition to bending in the horizontal plane when it is assumed that a “U” is drawn in the horizontal plane. By such an offset bend, the frame member 22 is easily deformed when subjected to a load, and the shock absorbing performance is improved. The offset in the bending direction is not necessarily 90 degrees, and an offset in an oblique direction such as 45 degrees is also possible.

  As shown in FIG. 4, notches 22c are formed on the left and right sides of the frame member 22 in the middle or in the vicinity of the main bent portion 22m as fragile portions whose cross-sectional area is smaller than other portions. By forming such a notch 22c in part, the structure can be relatively easily deformed when a large load is applied while maintaining the necessary rigidity of the entire frame member 22. In addition, by setting the position of the notch 22c in the middle or in the vicinity of the main bent portion 22m, it is possible to shorten the time from when the frame member 22 is loaded until it is deformed, and to reduce the impact on the occupant M. improves.

  FIG. 7 is a plan view showing another example of the frame member 22 used in the waist restraint device according to the present invention. In this example, the number of bends (number of subflexible portions 22s) is increased compared to the case of FIG. Thus, the frame member 22 becomes more easily deformed by increasing the number of bends. As in the case of FIG. 6, the frame member 22 is formed in a three-dimensional (three-dimensional) manner including a bend in a different direction such as a direction perpendicular to the paper surface in addition to forming the frame member 22 in a two-dimensional manner. You can also.

  FIG. 8 is an explanatory view (side view) showing the frame support member 30 of the waist restraint device 21 according to the first embodiment. Here, the frame support member 30 will be described with reference to FIGS. 4 and 8. On both the left and right sides of the frame member 22, a through hole 58 is formed at a substantially central portion in the front-rear direction. A hole 60 formed in the upper end portion of the frame support member (leg member) 30 for receiving the vertical load of the occupant M is disposed in correspondence with the hole 58.

  The frame support member 30 is formed into a concave arcuate plate shape as a whole in front of the vehicle, and is rotatably connected to the rotation lever 32 and the frame member 22 by a rotation shaft 31. A plurality of cutouts 30 a are formed in a stepped shape at the lower end of the frame support member 30, and can be stopped even while the frame member 22 is rotating, and is a locking mechanism that does not descend while the frame member 22 is rising. That is, the notch 30a of the frame support member 30 has a hook shape that can be forcibly locked in the hole 25a provided in the lower surface of the lower bracket 25, and the rotary shaft 31 is arranged so as to be easily locked in the hole 25a. It can be rotated (oscillated) as a fulcrum.

An elastic body 30b is disposed on the surface of the frame support member 30 opposite to the notch 30a. As the elastic body 30b, for example, a spring material having a substantially round cross section formed as shown in the figure, a molded resin material, a rubber material, or the like can be used.
The role of the elastic body 30b is to press the frame support member 30a so that the notch 30a can be easily locked.

  A rotation lever 32 that is coaxial with the rotation shaft 31 of the frame support member 30 is provided on the front side portion of the frame member 22 so as to be in rotational contact with the lower front portion of the top plate 23 in an approximately elliptical shape. Further, the front side end portion of the rotation lever 32 in FIG. 4 is rotatably connected to one end of the connection lever 33. As shown in FIG. 8, when the frame member 22 is lifted (deployed), the front edge of the top plate 23 is positioned above the frame member 22 by the operation of the rotating lever 32 and the connecting lever 33. Thereby, the waist | hip | lumbar part (buttock part) of the passenger | crew M can be received and supported not only by the frame member 22 but the surface of the top plate 23, and it becomes possible to reduce the load (impact) to a passenger | crew.

  The lever portion of the rotary lever 32 is formed with a bent shape 32a on the crank, and has a structure that provides a buffer function against the load on the passenger. Further, the buffering function can be further improved by providing the connecting lever 33 with a bent shape.

  FIG. 9 is a perspective view showing the operation of the waist restraint device 21 according to the first embodiment, where (A) is in a normal state (when the device is not operating), and (B) is a state when an impact is generated (when the device is operating). Indicates. Moreover, FIG. 10 is explanatory drawing which shows the simulation result of the waist | hip | lumbar part restraint apparatus 21 which concerns on an Example.

  When a situation such as a frontal collision of the vehicle occurs, the abnormal situation is detected by a known sensor (not shown), and the inflator 27 is operated. When the high-pressure gas generated by the operation of the inflator 27 is released into the metal bellows 24, the state transitions from the state shown in FIG. 9A to the state shown in FIG. That is, the metal bellows 24 is developed obliquely upward by the expanding gas.

  When the metal bellows 24 is unfolded, as shown in FIG. 9B, the frame member 22 connected to the metal bellows 24 by the bracket 24a rotates (rotates, swings) around two rotation shafts 29 at the left and right. Stand up. As a result, the front portion of the seat cushion 17 rises and restrains the occupant M from moving forward. At this time, a force from the pelvis Ma of the occupant M is applied to the rear side of the frame member 22, and the shock to the occupant M is absorbed or alleviated by deformation as shown in FIG.

  At this time, the thigh from the buttocks of the occupant M is supported by the top plate 23. As shown in FIG. 9 (B), the front edge of the top plate 23 is located above the frame member 22, so that the thigh is positioned higher than the pelvis and the forward movement is restrained well. Is possible.

  FIG. 11 is an exploded perspective view showing the structure of the waist restraint device according to the second embodiment of the present invention. Components that are the same as or correspond to those in the first embodiment described above are given the same reference numerals, and redundant descriptions are omitted. The basic difference between this embodiment and the first embodiment described above is the structure of the expansion means. That is, the metal bellows 24 is used as the expansion means in the first embodiment, whereas the fabric bag 130 is used in the present embodiment. Due to the difference in structure (mechanism) of the expansion means, there are also differences in the surrounding structure.

  The woven fabric bag 130 is formed by sewing a woven fabric into a “rectangular shape” having a long side in the lateral direction of the vehicle, using a nylon material. Or oval). Further, the fabric is used in a direction perpendicular to the inflating and deploying direction, and in order to maintain the necessary inflating and deploying height dimension accompanying the unnecessary inflating in the transverse direction, one or more stretches (tethers) ) Can be provided by sewing or the like.

  In addition, in the case of a cylindrical bag, as a substitute for the above-mentioned tension (tether), by providing a coil-shaped cover on the outer peripheral portion, the unnecessary expansion in the lateral direction and the necessary expansion height dimension associated therewith are maintained.・ It can be secured. The coil-shaped cover of the outer peripheral portion can be made of metal, resin, or fabric material.

  The smaller the bag capacity, the higher the bag internal pressure and the higher the inflation and deployment speed, which is desirable. However, since the pressure resistance of the fabric is limited, when a small inflator MGG is used, the pressure is 250 KPa or less, and the bag capacity is desirably 2 L or less.

  In addition, the integrated shape of the fabric bag in the normal state (when the device is not in operation), that is, the folding method is a bellows shape that is bent with respect to the inflating and unfolding direction, thereby minimizing the resistance during inflating and unfolding. be able to.

  Here, the “woven fabric” refers to a fabric woven with a combination of warp and weft, and includes fabric and fabric. As described above, nylon can be used as the material used for the fabric bag of the present invention. However, in order to improve the airtightness, a nylon-coated material can be used.

  In FIG. 11, as in the first embodiment, the lower bracket 125 is fixed to the seat frames 12 and 13 by fixing bolts 34 at the lateral sides. In FIG. 11, the left part of the lower bracket 125 is shown in an exploded state, and the right part is shown in a partially assembled state. An inclined mounting surface 125b for storing the fabric bag 130 is formed at the substantially central portion of the upper surface of the lower bracket 125. Further, a through hole 27a for incorporating a cylindrical inflator case 26 holding the inflator 27 is formed at the center bottom of the inclined mounting surface 125b.

  The inflator case 26 that houses the inflator 27 is screwed into the bottom surface of the fabric bag 130 and is fixed by a cap 28. Further, a retainer with a bolt (not shown) is inserted into the fabric bag 130 and is fixed by four fixing nuts 139 from the bottom side (back side) of the inclined mounting surface 125b.

  By arranging the fabric bag 130 on the inclined mounting surface 125b, the bag 130 can be deployed linearly. As shown in FIG. 2-3, since the lower bracket 125 is disposed to be inclined from the horizontal direction at the lower part of the seat cushion, the inclined mounting surface 125b is substantially horizontal. Therefore, it can be said that the inclined mounting surface 125b is kept horizontal by being inclined with respect to the lower bracket 25.

  As shown in FIG. 11, a bracket 130 a is provided on the upper portion of the fabric bag 130 and is fixed to the frame member 22 by two fixing bolts 135. The two fixing bolts 135 are screwed into two screw holes 52 formed substantially at the center of the frame member 22.

  Since the fabric bag 130 is more flexible than the metal bag, the upper portion of the fabric bag 130 needs to be fixed to the top plate 123 as a whole. A plurality of fixing flanges 123 a are formed on the front edge portion of the top plate 123. A plurality of holes are formed at positions corresponding to the fixing flange 23a of the flange 130a, and the fixing flange 123a is inserted into the holes and fixed by caulking.

  The top plate 123 has side portions extending substantially vertically downward at the left and right edge portions, and a long hole 123b in which one end of the rotation lever 32 is slidably supported via the rotation shaft 138 is provided on the side surface portion. Is provided. The top and bottom rotations of the top plate 123 are limited within a certain range by sliding the rotary shaft 138 inside the long hole 123b. That is, by allowing the rotary lever 32 to rotate and slide only within the range of the elongated hole 123b, the front edge of the top plate 123 moves to a position higher than the frame member 22, but does not rise more than necessary. Yes.

  FIG. 12 is an exploded perspective view showing the structure of the waist restraint device according to the third embodiment of the present invention. Note that the same or corresponding components as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description is omitted. The basic difference between this embodiment and the first embodiment described above is the structure of the top plate disposed above the metal bellows 24. That is, the top plate of the first embodiment has a simple flat plate shape, whereas a receiving tray 223a for receiving the metal bellows 24 is provided on the back surface of the top plate 223 of the present embodiment. Hereinafter, the present embodiment will be described in comparison with the first embodiment and the second embodiment.

  In the first embodiment shown in FIG. 4, a bracket 24 a for connecting to the top plate 23 is provided on the upper part of the metal bellows 24. On the other hand, in this embodiment, no bracket is provided on the upper part of the metal bellows 24, and the upper part of the metal bellows 24 is substantially fixed to nothing. The shape of the top plate 223 adopts the same structure as that of the second embodiment shown in FIG. As described above, the feature of this embodiment is that the tray 223 a is provided on the bottom surface of the top plate 223.

  As in the first embodiment, the cross section of the metal bellows 24 is preferably circular, oval or elliptical. In the case of the present embodiment, it is circular. The tray 223a is in contact with the upper surface of the metal bellows 24 and regulates the unfolding direction of the bellows 24, and is formed in an inverted bowl shape (convex hemispherical shape). In addition, the tray part 223a is formed in an elliptical shape that is longer in the front-rear direction than in the left-right direction, thereby guiding the metal bellows 24 when deployed in a straight line. Details will be described later with reference to FIGS.

  Forming the tray part 223a into an elliptical shape that is long in the front-rear direction is also because the hole formed in the side surface of the top plate 223 does not hinder the function of the long hole 223b. That is, the rotation lever 32 can be rotated and slid only within the range of the elongated hole 223b, and the metal bellows 24 can be moved within the range of the elliptical tray 223a, so that the front edge of the top plate 223 is a frame. Although it moves above the member 222, it does not rise more than necessary. In addition, the top plate 223 and the tray 223a can be formed as a separate part, or can be integrally formed of resin or the like.

  A fragile portion including a plurality of slits (notches) 222 c is formed in the left and right bent portions behind the frame member 222. By forming such a notch 222c in part, the structure can be relatively easily deformed when a large load is applied while maintaining the necessary rigidity of the entire frame member 222. Further, by forming the position of the notch 222c inside the bent portion, it is possible to shorten the time from when the frame member 222 is loaded until it is deformed, and the impact mitigating performance to the occupant M is improved.

  The width, depth, length, and number of slits can be determined in consideration of the rigidity of the frame member 222, the curvature of the bent portion, and the like. That is, the frame member 222 is set to be deformable so that the load from the occupant can be absorbed satisfactorily while maintaining the rigidity of the frame member 222 to the extent that the occupant's restraining performance is not impaired.

  In the present embodiment, in a normal state (when the apparatus is not operating), as shown in FIGS. 13 and 14, the metal bellows 24 is accommodated between the lower bracket 25 and the top plate 223 in a compressed state. At this time, the metal bellows 24 is in contact with the front end side (right end in FIG. 14) of the tray 223a.

  Next, when an impact occurs (when the apparatus is in operation), as shown in FIGS. 15 and 16, when the metal bellows 24 is inflated and deployed obliquely upward, the top plate 223 rotates with the rotary shaft 138 as a fulcrum. Move. At this time, the upper surface of the metal bellows 24 slides to the rear end side (left end in FIG. 16) along the inner side of the tray 223a. The deployment of the metal bellows 24 causes the frame member 222 to rotate and move in conjunction with the top plate 223 (see FIG. 9).

  The top plate deformation guide hole 224 is formed in the shape of a long hole illustrated in the top plate 223 on the contact surface between the top plate 223 and the frame member 222, so that the front edge of the top plate 223 is expanded by the expansion of the metal bellows 24. However, it plays the role of the shaft 36 shown in FIG. 4 that moves above the frame member 222. That is, the top plate deformation guide hole 224 is provided in the shape of a long hole as a guide for plastic deformation, and performs the same operation (function) as the shaft 36.

  As mentioned above, although the Example of this invention was described, this invention is not limited to these Examples at all, It can change in the category of the technical idea shown by the claim.

FIG. 1 is a plan view showing a structure of a waist restraint device according to a first embodiment of the present invention and an arrangement in a lower part of a vehicle seat (seat cushion omitted). FIG. 2 is a side view showing the structure of the waist restraint device according to the first embodiment and the arrangement inside the vehicle seat, and shows a normal state (when the device is not operating). FIG. 3 is a side view showing the structure of the waist restraint device according to the first embodiment and the arrangement inside the vehicle seat, and shows a state when the impact is generated (when the device is operating). FIG. 4 is an exploded perspective view showing the structure of the waist restraint device according to the first embodiment. FIG. 5 is a partial side view showing the structure of the main part of the waist restraint device according to the first embodiment. FIG. 6 is a plan view showing an example of a frame member used in the waist restraint device according to the present invention. FIG. 7 is a plan view showing another example of a frame member used in the waist restraint device according to the present invention. FIG. 8 is an explanatory view (side view) showing the structure (frame support structure) of the main part of the waist restraint device according to the first embodiment. FIG. 9 is a perspective view showing the operation of the waist restraint device according to the first embodiment, in which (A) shows a normal state (when the device is not operating) and (B) shows a state when an impact is generated (when the device is operating). Show. FIG. 10 is an explanatory diagram illustrating a simulation result of the waist restraint device according to the first embodiment. FIG. 11 is an exploded perspective view showing the structure of the waist restraint device according to the second embodiment of the present invention. FIG. 12 is an exploded perspective view showing the structure of the waist restraint device according to the third embodiment of the present invention. FIG. 13: is a perspective view which shows the structure of the principal part of the waist | hip | lumbar part restraint apparatus based on 3rd Example, and shows a normal state (at the time of apparatus non-operation). FIG. 14 is a partial cross-sectional view showing the structure of the main part of the waist restraint device according to the third embodiment, and shows a normal state (when the device is not operating). FIG. 15 is a perspective view showing the structure of the main part of the waist restraint device according to the third embodiment, and shows the time of occurrence of an impact (when the device is operating). FIG. 16: is a fragmentary sectional view which shows the structure of the principal part of the waist | hip | lumbar restraint apparatus which concerns on 3rd Example, and shows the time of an impact generation (at the time of apparatus operation).

Explanation of symbols

21 Lumbar restraint devices 22, 222 Frame members 22c, 222c Notches 23, 123, 223 Top plate 24 Metal bellows 27 Inflator (MGG)
29 Rotating shaft 30 Frame support member 130 Fabric bag 223a Bellows tray

Claims (12)

In a waist restraint device that restrains the waist of an occupant seated on a seat in a vehicle,
Gas supply means for supplying an expanding gas when an impact occurs;
Expansion means accommodated in a compressed state in a lower portion of a seating portion (hereinafter referred to as “seat cushion”) of the seat and inflated and expanded upward by the inflation gas;
A frame member disposed at a lower portion of the seat cushion and restraining forward movement of an occupant by pushing up the seat cushion by deployment of the inflating means;
The frame member as a whole is formed into a U shape with the open part facing the front side of the vehicle, and the corners at two locations are bent with roundness,
By the expansion of the expansion means, the frame member moves upward,
The waist restraint device, wherein the frame member has a structure that absorbs an impact to the occupant by being deformed by a load from the occupant forward of the vehicle.   The frame member has two bent portions (hereinafter referred to as “main bent portions”) that form the U-shape, or at least two or more other bent portions (hereinafter referred to as “sub-bent portions”). The waist restraint device according to claim 1, wherein the waist restraint device is provided on the open side of the main bent portion.   The lumbar restraint device according to claim 2, wherein when the main bent portion is bent in a horizontal plane, the sub-bent portion is bent in a substantially vertical direction.   The waist restraint device according to claim 1, 2 or 3, wherein the frame member has a weakened portion having a cross-sectional area smaller than that of the other portion.   The waist restraint device according to claim 4, wherein the fragile portion is a notch formed in the frame member.   6. The waist restraint apparatus according to claim 5, wherein the notch has a configuration in which a plurality of thin slit-like cuts are formed.   The waist restraint device according to claim 4, 5 or 6, wherein the fragile portion is formed between the main bent portion and the open-side end portion.   The waist restraint device according to claim 4, 5, 6, or 7, wherein the weakened portion is formed in the main bent portion. A lower bracket for holding at least the gas supply means and the expansion means;
Two rotation support structures that rotatably support the front side of the frame member with respect to the lower bracket;
The waist part according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the rotation support structure part is provided with a rotation restricting member for restricting the rotation of the frame member. Restraint device. The rotation restricting member is an auxiliary bracket configured integrally with the lower bracket,
In a non-deployed state, it does not interfere with the end portion of the frame member, and has a stepped portion that meshes with the end portion of the frame member when deployed,
The waist restraint device according to claim 9, wherein the waist restraint device is configured to support a load applied to the frame member by the occupant during deployment.   The waist restraint apparatus according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, wherein the frame member is made of aluminum, magnesium, or an alloy thereof.   The waist restraint apparatus according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, wherein the gas supply means is an MGG (micro gas generator).

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