Seat unit restraint device
The restraint device with a non-inflatable element addresses the issue of airbag deviation during collisions by maintaining airbag position and absorbing impact forces, enhancing occupant protection.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- AUTOLIV DEV AB
- Filing Date
- 2024-05-23
- Publication Date
- 2026-05-15
AI Technical Summary
Front airbags in vehicles often flex and deviate when struck by the head during a frontal collision, leading to insufficient protection of the occupant.
A restraint device with a non-inflatable restraint element extending from the front to the side of the airbag, connected via seams, to maintain the airbag's position and absorb impact forces, optionally incorporating a fold for controlled displacement.
The non-inflatable restraint element effectively holds the airbag in place, reducing excessive impact forces on the occupant's head and providing reliable protection, especially in frontal collisions.
Smart Images
Figure 2026515302000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a restraint device for a seat unit described in the preamble of claim 1, a restraint assembly including such a restraint device and an inflater as described in claim 11, and a seat unit including a vehicle seat as described in claim 12 and at least one such restraint assembly.
Background Art
[0002] Almost all modern passenger cars, vans, etc. include at least two front airbags, one being a driver's airbag (driver airbag) and one being a front passenger's airbag (passenger airbag). These front airbags are attached to vehicle structural components, usually the steering wheel or the instrument panel, and are thus supported by this structural element. Further, it is common to equip vehicle seats with at least one side airbag that deploys from the seat back. Many of today's passenger cars have front airbags and side airbags that are independent.
[0003] To be independent of the vehicle's support structure (e.g., the steering wheel and instrument panel) and / or to provide additional protection, a combination of a side airbag and a front airbag is proposed, which includes a side portion surrounding a side chamber and attached to the seat back, and a front portion surrounding a front chamber and attached to the side portion, with the front chamber in fluid communication with the side chamber. In the deployed state of the airbag, the side portion extends from the rear end portion to the front end portion of the side portion attached to the seat back, and also from the lower end portion to the upper end portion of the side portion, and the front portion extends from the outer end portion to the inner end portion of the front portion connected to the side portion, and also from the lower end portion to the upper end portion. In other words, the deployed side portion extends laterally from a person sitting on the vehicle seat, and the front portion is held by the side portion (filled through the side portion) and is positioned essentially in front of the head of a person sitting on the vehicle seat, or in front of at least a part of the head and chest. [Overview of the project]
[0004] Building upon this prior art, the object of the present invention is to improve a restraint device having side and front airbags so as to improve its ability to protect a person seated in a vehicle seat, particularly in the event of a frontal collision.
[0005] This objective is achieved by a restraint device having the features described in claim 1. A restraint assembly further comprising an inflator is defined in claim 11, and a seat unit comprising a vehicle seat and at least one such restraint assembly is defined in claim 12.
[0006] In the absence of external support, the front of an airbag often tends to flex and deviate when struck by the head of the person it is intended to protect, resulting in insufficient protection of that person in a frontal collision. To prevent this deviating motion, a non-inflatable restraint element is provided, extending from a first connection section connected to the front of the airbag when the airbag is deployed, to a second connection section connected to at least one of the vehicle seat and a portion of the restraint device located behind the front. This non-inflatable restraint element can transmit force in the longitudinal direction, thereby effectively holding the front of the airbag in its initial position, even when struck by the person it is intended to protect, particularly their head.
[0007] Since this non-inflatable restraint element must not interfere with the head of the person to be protected, it is preferable that the non-inflatable restraint element extends from the upper end of the front to the upper end of the side. This further simplifies the manufacturing process and ensures reliable and repeatable deployment behavior.
[0008] The non-expandable restraining element has only one role, namely restraining the front, and for this reason, it is preferable that it be as simple and lightweight as possible. Therefore, in a preferred embodiment, it is a flat element, preferably a flat fabric element.
[0009] The forces acting on the connection section are relatively large, and for this reason, the constraint element is often preferably in an essentially triangular or trapezoidal shape, such that the front connection portion of the constraint element extends between its outer end and its inner end along at least half the length of the front section.
[0010] Typical front airbags are relatively soft for strong ventilation, and a person is decelerated as they jump into the front airbag under energy dissipation. In contrast, the combined side-front airbags according to the present invention are often not ventilated and are therefore relatively rigid. To compensate for this, the non-inflatable restraint element may preferably include at least one fold between the front and rear connecting sections, which is initially held by a rupturing connection, for example, in the form of at least one ruptured seam. When the tension of the restraint element exceeds a predetermined value, the rupturing connection ruptures (under energy dissipation), increasing the distance between the first and second connecting sections, allowing the front to be displaced in a controlled manner, thereby preventing an excessively violent impact on the person (especially their head). This fold may be a simple U-shape with two legs connected by a rupturing connection.
[0011] In a particularly preferred embodiment, the restraint device is designed to adequately protect an occupant not wearing a seatbelt. For this reason, the airbag of the restraint device further includes a shoulder portion that extends along the inner surface of the side portion in such a manner that it further extends over the shoulder of the person to be protected, and in some embodiments, this shoulder portion further extends along at least a portion of the chest of the person to be protected. This shoulder portion surrounds a shoulder chamber that is in fluid communication with at least one of the side chamber and the front chamber. Preferably, this shoulder portion is connected to both the side and the front portion so that the shoulder portion further contributes to frontal restraint in the event that the front portion strikes the person. Particularly in this configuration, the restraint device is suitable for a vehicle seat that can change position and / or orientation, as is often the case in autonomous vehicles.
[0012] In the above case, it is even more preferable to provide a first belt for restraining the airbag, extending from a first end connected to the seatback to a second end connected to the seat. This first belt is preferably attached to the shoulder and, in some embodiments, preferably extends through a front tunnel. This provides additional restraint to the front and expands the possibility of designing the front at a higher height.
[0013] In particular, if the orientation of the vehicle seat can be selected, it is preferable that the seat unit includes two restraint assemblies, one positioned on the left side of the vehicle seat and the other on the right side of the vehicle seat. [Brief explanation of the drawing]
[0014] Herein, the present invention will be described in more detail by preferred embodiments with reference to the figures. The figures are as follows: [Figure 1] Figure 1 is a schematic side view of a seat unit including a vehicle seat and a restraint device, in which the airbag of the restraint device is fully deployed and a person is seated in the vehicle seat. [Figure 2] Figure 2 shows the items shown in Figure 1, viewed from direction R1 in Figure 1, but the person's legs and seat are not shown. [Figure 3] Figure 3 shows the items from Figure 2 after the person's head and chest have moved forward relative to the airbag and the head has struck the front impact surface. [Figure 4] Figure 4 is a modified representation of the embodiment shown in Figures 1 to 3, following the same representation as in Figure 2, but without the presence of people. [Figure 4a] Figure 4a is a cross-sectional view along plane AA in Figure 4. [Figure 5] Figure 5 shows the item shown in Figure 4 after a force in the direction of the arrow in Figure 5 is applied to the front impact surface. [Figure 6] Figure 6 shows a second embodiment of the present invention in which the airbag of the restraint device is not deployed. [Figure 7]Figure 7 shows the item shown in Figure 6 in a state where the airbag is fully deployed (according to Figure 1). [Figure 8] Figure 8 is a view of some of the items in Figure 7 as seen from direction R2 in Figure 7. [Figure 9] Figure 9 is a view of the item shown in Figure 7 as seen from direction R3 in Figure 7, but the person and the seat are not shown. [Figure 10] Figure 10 is a modified example of that shown in Figure 9. [Figure 11] Figure 11 is a further modified example of that shown in Figure 9. [Figure 12] Figure 12 shows a seat unit having two restraint devices arranged on the right and left sides of a vehicle seat. [Figure 13] Figure 13 shows another embodiment having two restraint devices. [Figure 14] Figure 14 shows the cut portions necessary for forming an airbag as shown, for example, in Figure 7. [Figure 15] Figure 15 is a side view of a completed airbag sewn to form the cut portions shown in Figure 14.
Mode for Carrying Out the Invention
[0015] Prior to the description of the preferred embodiments, the following definitions selected for this description and the entire patent application need to be defined.
[0016] To explain the present invention in easily understandable terms, the terms “front” and “rear” are used herein and in the claims. These terms refer to the vehicle seat in the sense that the seatback forms the rear of the vehicle seat and the seat extends from the seatback to the front end. In some vehicles, or in some configurations of a vehicle, the vehicle seat may be oriented such that the seat extends from the seatback to the rear or laterally of the vehicle. Therefore, the terms “front” and “rear” do not necessarily refer to orientation relative to the vehicle, but only to orientation relative to the vehicle seat in the sense described above. Thus, the front of the airbag, as described later, always faces the seatback (when the airbag is deployed) and faces the occupant, particularly the occupant's head, when seated in the vehicle seat, but may not be forward with respect to the direction of travel of the vehicle. Similarly, the terms “left” and “right” should be understood as the left side of the vehicle seat being the side where the left side (e.g., left arm) of a person seated in the vehicle seat is located, and the right side of the vehicle seat being the side where the right side of the occupant is located.
[0017] Figures 1 to 3 show a first embodiment of a seat unit according to the present invention. The seat unit includes a vehicle seat 10 having a seat 12 and a seat back 14. Furthermore, as is common in the prior art, a headrest extends from the seat back. Of course, the headrest may be integrated with the seat back. Furthermore, in this first embodiment, a restraint assembly is provided, which includes a restraint device in the form of an airbag 20 and an inflator 60. Figures 1 to 3 show the airbag 20 in a fully deployed state.
[0018] In this first embodiment, the airbag 20 is composed of two parts, namely, a side part 30 surrounding the side chamber and a front part 40 surrounding the front chamber. The side part 30 is substantially in the form of a conventional side airbag extending from the rear end part 40a to the front end part 40b and also from the lower end part 40c to the upper end part 40d. The side part 30 is of a large size so as to cover substantially the whole chest and head of a person P of standard build sitting on the vehicle seat 10 (when viewed from the side). This means that the upper end part 40d is located at a height above that of the headrest. The inflator 60 is attached to the frame of the seat back 14 and is disposed inside the side part 30 in the same manner as the side airbag.
[0019] The front part 30 of the airbag 20 extends substantially parallel to the seat back 14 from the front end part 40b of the side part, whereby it is substantially positioned in front of the head and, in this embodiment, also substantially in front of the upper chest of the person P. Therefore, the front part 30 extends from the outer end part 40a (which coincides with the front end part 30b of the side part) to the inner end part 40b and also from the lower end part 40c of the front part to the upper end part 40d of this front part 40.
[0020] As can be seen particularly in Figure 2, the non-inflatable restraint element 90, also called a "sail" due to its shape, extends from the front 40 to the side 30. In the illustrated embodiment, although this is generally preferred, the non-inflatable restraint element 90 extends from the upper front 40d to the upper side 30d. The non-inflatable restraint element 90 is preferably a fabric element, and in particular can be formed from standard airbag material. Usually, a single layer is sufficient. The non-inflatable restraint element 90 is connected to the front 40 via a first connecting section 91 of the non-inflatable restraint element and to the side 30 via a second connecting section 92 of the non-inflatable restraint element. In the illustrated embodiment, although this is often preferred, these connecting sections 91 and 92 also constitute the end sections of the non-inflatable restraint element 90. This is because, although it is certainly possible for the non-inflatable restraint element 90 to extend beyond the connecting sections 91 and 92, there is little need for it. The first connecting section 91 is connected to the front section 40 by a first connecting section 91a, which may be in the form of a first seam. Similarly, the second connecting section 92 is connected to the upper end 40d of the side section by a second connecting section 91a, which may be in the form of a second seam. The first connecting section, and therefore the first connecting section, preferably extends along a substantial length of the front section 40, i.e., along at least half the distance between the outer end 40a and the inner end 40b. Similarly, the second connecting section 92 preferably extends along a substantial length of the side section 30, between its rear end 30a and its front end 30b. The two connecting sections each define a direction, and these two directions are substantially perpendicular to each other.
[0021] The effect of this non-expandable restraining element 90 can be directly seen from Figure 3, which shows the situation after a person P, particularly their head, collides with the inner surface 42 (impact surface) of the front part 40. Due to the non-expandable restraining element 90, the front part is substantially unable to deviate in a way that restrains the person P, particularly their head.
[0022] Figures 4, 4a, and 5 show variations of the above-described configuration. The general configuration is as described with reference to Figures 1 to 3, but the non-expandable restraining element 90 exhibits an additional feature, namely a fold 94 fixed to itself by a breaking seam 96. In this embodiment, the fold 94 is a simple fold having a U-shaped cross-section, but it is also possible to provide folds with more complex shapes. The fold is located in the intermediate section between the first connecting section 91 and the second connecting section 92 and extends laterally, meaning that the fold does not connect the first connecting section to the second connecting section, and as a result the fold shortens the distance between the connecting sections 91 and 92.
[0023] A force in the direction of the arrow shown in Figure 5 is applied to the impact surface 42 of the front section 40. When this force exceeds a predetermined value, the rupture seam 96 tears, causing the non-inflatable restraining element 90 to return to its original length, and the front section 40 rotates by a determined angle around the connection point with the side section. This simulates to some extent the behavior of conventional front airbags, which are usually relatively soft due to their strong ventilation. This means that some of the kinetic energy of the person P is dissipated, and the force peak is reduced.
[0024] Figures 6 to 9 show a second embodiment. The main difference from the first embodiment is that the restraint device further includes a first belt 71, and the airbag of the restraint device further includes a shoulder portion 50. This means provides a fully self-restraining safety device, in particular, that does not necessarily require the occupant to wear a seat belt.
[0025] Figure 6 shows the seat unit with the restraint device's airbag 20 in a non-deployed state. The packed airbag 21 is positioned inside or along the seatback 14, with a first belt 71 extending from a first end 71a attached to the seatback to a second end 71b attached to the front end of the seat 12. This first belt 71 is attached to the aforementioned shoulder portion 50 of the airbag 20, as will be described later with reference to Figure 9 in particular, and extends through a tunnel 44 in the front portion 40, as can be seen particularly in Figure 8. The structure of the restraint device of the second embodiment, particularly its airbag, is best illustrated in Figures 7 and 9. The side portions 30 of the airbag 20, the front portion 40 of the airbag 20, and the non-inflatable restraint element 90 are positioned similarly to those of the first embodiment, and this embodiment can be fully referenced. Although not shown in Figure 9, it is also possible that the non-inflatable restraint element 90 of this second embodiment shows a fold secured by a break seam or another breakable connection. The shoulder portion 50 is connected to the inner surface 42 (impact surface) of the front portion and the inner surface 42 (similarly an impact surface) of the side portion 30. Furthermore, the shoulder chamber enclosed by the shoulder portion 50 is in fluid communication with at least one of the front chamber and the side chamber. In the illustrated embodiment, the connection of the shoulder portion 50, i.e., its upper surface to the first belt 71, is formed by a load-bearing patch 80. The function of the non-inflatable restraining element 90 is the same as in the first embodiment, preventing the front portion 40 from tilting when struck by the head of a person P.
[0026] Figure 10 shows a third embodiment. This embodiment further includes a second belt 72, the first end 72a of which is also attached to the backrest 14, preferably to the upper end of the backrest 14. The first belt 71 and the second belt 72 can use the same bracket 75 for this attachment. The second belt 72 is also attached to the upper surface of the shoulder portion 50, and a joint load-bearing patch 80' may be used for this purpose, as shown in Figure 10. In contrast to the first belt 71, the second belt 72 extends through a second tunnel 41 in the side portion 30, rather than extending through the first tunnel 51. The second end of the second belt 72 is also attached to the seat, particularly in the area of the seat 12, and the lower section of the second belt 72 extends along the outer surface of the lower section of the side 30, so that the second belt 72 prevents the airbag cushion, particularly its side 40, from moving in the -Y direction, even when there is no support surface (such as an internal vehicle structure, like a door), and thus the occupant is also restrained in this direction. Thus, in this embodiment, the restraint device is entirely self-supporting and does not require a support surface.
[0027] Alternatively, the second belt 72a may extend over the upper end 30d of the side portion 30 such that one section of the second belt extends along the entire height of the outer wall of the side portion 30. This alternative example (according to Figure 10) is shown in Figure 11.
[0028] Figure 12 shows a third embodiment of the representation in Figure 9. Here, two restraint assemblies are provided, one on the right side of the vehicle seat and the other on the left side. In principle, these two restraint devices may be mirror symmetric, but it is often preferable that they are not. In particular, one of the front parts can be larger than the other, and the boundary between these two front parts is offset from the central axis of the vehicle seat. With this means, the forward restraint function is mainly performed by one of the two restraint devices, and therefore, as described above, because there is a fold in the non-expandable restraint element, even if the two front parts are allowed to pivot, the occupant's head cannot slide through the two front parts.
[0029] As can be seen from Figure 13, this "duplication" of restraint devices can also be applied when each restraint device contains only one belt. It is also possible to have one restraint device with one belt and another restraint device with two belts.
[0030] As mentioned above, although not shown in Figures 6 to 13, all non-expandable constraint elements shown in these figures can be given a fold with a fractured connection.
[0031] Figure 14 schematically shows an example of cuts required to manufacture an airbag according to a second embodiment. While Figure 14 shows only the strictly necessary cuts, additional cuts can, of course, be used to form, for example, reinforcing layers, inner tethers, etc. However, these are not shown as they are not necessary to understand the structure. Furthermore, outer tethers or other outer elements can be used, for example, in the form of at least one sail connecting at least two parts to provide additional restraint elements. In the illustrated embodiment, only four cuts are required: a first cut 100 for the shoulder section, a second cut 110 for the side and front sections, and a cut 120 for the tunnel wall. Both the first cut 100 and the second cut 110 are of the "butterfly" type, meaning they fold along fold lines F1 and F2, respectively. Of course, the present invention is not limited to the types of cuts shown herein. For example, each layer may be made from separate cuts. Furthermore, it is not essential to provide joint cuts for the layers of the first and third sections.
[0032] The first cut section 100 indicates at least one overflow opening 102 (in this case, two overflow openings), and the second cut section 110 indicates the corresponding overflow opening 112. Furthermore, the second cut section 110 indicates two holes 114 for the first tunnel and two holes 115 for the second tunnel. In addition, there is a hole 116 for the inflator stud, as is commonly known from side airbags.
[0033] The sewing process can be as follows, for example: First, the first cut section 100 is sewn to the second cut section 110, particularly around the overflow openings 102, 112. After this, the first cut section 100 can be folded and closed with edge seams to form the shoulder section. Next, the cut section 120 for the tunnel wall can be sewn to the edges of the respective holes 114, 115, and then the shoulder section can be sewn to the cut section 110 by the protruding section 104 of the first cut section 100. Finally, edge seams can be applied to close the cut section 110 to form the side and front sections. Since the shoulder section is connected to both the side and front sections, the front section is automatically bent from the side plane, and the fully sewn airbag looks as shown, for example, in Figure 9. [Explanation of Symbols]
[0034] 10 seats per vehicle 12 seats 14 Seatback 20 airbags 21 Packed Airbags 30 Side 30a Rear end of the side 30b Front end of the side 30c Lower end of the side 30d Upper end of the side 32 Inner surface (collision surface) 34 Exterior 36 (Fabric) element for fastening the belt to the first part 40 front 40a Front outer end 40b Front inner end 40c Front lower end 40d Front upper end 42 Inner surface (collision surface) 44 Exterior 44 Tunnel passing ahead 50 Shoulder 50a Rear end of the shoulder 50b Front end of the shoulder 60 Inflator 71 First Belt 71a First end (attached to the seat back) 71b Second end (attached to the seat) 72. The second belt 72a First end (attached to the seat back) 75 Bracket 80 Load-bearing patches 90 Non-expandable constraint element (sail) 91 First Connection Section 91a First connection section (first seam) 92 Second Connection Section 91a Second connection (second seam) 94 folds 96 Breaking seams 100 Cutting section for the first part 102 Overflow opening 104 Protruding section for sewing to the third part 110 Cutting section for the second and third parts 112 Overflow opening 114 Hole for the first tunnel 115 Hole for the second tunnel 116 holes for inflator studs 120 Cut section for tunnel wall 130 Molding elements 130a First (inner) section 130b Section 2 132 holes for inflator studs 134 Connection (sewing) / Sewing position 134a, b Connection section 136 Closure Seam FL1, FL2 folding lines P person
Claims
1. A restraint device for a seat unit, wherein the seat unit further includes a vehicle seat (10) comprising a seat back (14) defining the rear end of the vehicle seat (10) and a seat extending from the seat back (14) to the front end of the vehicle seat (10), The restraint device includes an airbag (20) having a side portion (30) that surrounds the side chamber and is attached to the seat back (14), and a front portion (40) that surrounds the front chamber and is attached to the side portion (30), wherein the front chamber is in fluid communication with the side chamber. In the deployed state of the airbag (10), The side portion (30) extends from the rear end portion (30a) attached to the seat back (14) to the front end portion (30b) of the side portion (30), and from the lower end portion (30c) to the upper end portion (30d) of the side portion. The front portion (40) extends from the outer end (40a) of the front portion connected to the side portion (30) to the inner end (40b) of the front portion, and from the lower end (40c) of the front portion to the upper end (40d) of the front portion. A restraint device characterized in that a non-inflatable restraint element (90) extends from a first connection section (91) connected to the front part (40) of the airbag (20) to a second connection section (92) connected to at least one of the parts of the restraint device located behind the vehicle seat (10) and the front part (40) when the airbag is deployed.
2. The restraint device according to claim 1, characterized in that the non-expandable restraint element (90) extends from the upper end of the front portion (40) to the upper end of the side portion (30).
3. The restraint device according to claim 1 or 2, characterized in that the non-expandable restraint element (90) is a flat element, preferably a flat cloth element.
4. The restraint device according to claim 3, characterized in that the non-expandable restraint element (90) is essentially triangular or trapezoidal in shape, and a first connecting section (91) of the restraint element (90) extends between its outer end (40a) and its inner end (40b) along at least half the length of the front portion (40).
5. The restraint device according to any one of claims 1 to 4, wherein the non-inflatable restraint element (90) includes at least one fold (94) between the first connection section (91) and the second connection section (92), the fold (94) is initially held by a breaking connection, which is preferably in the form of at least one breaking seam (96), the breaking connection breaks when the tension of the non-inflatable restraint element (90) exceeds a predetermined value, and the distance between the first connection section (91) and the second connection section (92) increases.
6. The restraint device according to claim 4, characterized in that the fold (94) is U-shaped and has two legs connected by the fracture connection portion.
7. The restraint device according to any one of claims 1 to 6, characterized in that the airbag further includes a shoulder portion (50) extending along the inner surface (32) of the side portion (30).
8. The restraint device according to any one of claims 1 to 7, further comprising a first belt (71) extending from a first end (71a) connected to the seat back (14) to a second end (71b) connected to the seat (12).
9. The restraint device according to claim 8, characterized in that the first belt (71) extends through the tunnel (44) of the front portion (40).
10. The restraint device according to any one of claims 7, 8, or 9, characterized in that the first belt (71) is attached to the shoulder portion (50).
11. A restraint assembly comprising a restraint device according to any one of claims 1 to 10, and an inflator (60) that is in fluid communication with the side portion (30) of the airbag (20).
12. A seat unit comprising a vehicle seat (10) and at least one restraint assembly as described in claim 11, wherein the rear end (30a) of the side portion (20) of the airbag (10) of the at least one restraint assembly is attached at least indirectly to the seat back (14) of the vehicle seat.
13. The seat unit according to claim 12, comprising two restraint assemblies, one of which is positioned to the left of the vehicle seat (10) and the other being positioned to the right of the vehicle seat (10).