JPH04232143A - Seat belt device for vehicle and web thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to seat belt systems for vehicle occupants, and more particularly to the web of the seat belt.

0002

BACKGROUND OF THE INVENTION Seat belts for vehicle occupants are formed from an elongated strap material known as a web. Seat belt devices typically include a web, a retractor assembly around which the web is wound, and means for releasably locking the web in an extended position around a vehicle occupant.

There are different types of seat belt devices: active and passive. Active seat belt systems require the occupant to move the web into an extended position and fasten the web in place around the occupant. A locking tong is held on the web for manual insertion into the clasp. The locking tongs can be connected to the web or can slide freely along the web. The web is wound onto a spool of one retractor assembly. The spool is spring biased in the direction of winding the web onto the spool. The spool and spring pull out the web and move the web to the extended position and
It is possible to respond to the normal movements of passengers within the vehicle. The spool is biased by a spring and pulls the web away from the occupant when the web is taken up to take up slack or when the locking tongue is released from the clasp.

Passive belt systems do not require any operation by the passenger. Typically, in passive seat belt systems, the web automatically moves to a fastened position centered on the occupant when the vehicle door is closed or the engine is started. In one type of passive seat belt device, one end of the web is connected to a retractor assembly spool while the other end of the web is connected to a movable anchor that slides along an elongated track. A motor moves the anchor back and forth along the track, moving the web into and out of position where it extends about the occupant.

[0005]

A desirable feature of the web of an active or passive seat belt device is to minimize the loading on the motor driving the spring-driven retractor spool and/or anchor. It's lightweight. Another desirable feature of a seat belt web is to have some lateral stiffness that resists folding or folding across the width of the web. Thereby, the web can be mounted on the retractor assembly with a locking tongue that slides along the length of the web and/or a D-ring that supports the web on the vehicle pillar adjacent the occupant's shoulders. The web can be easily moved through the guide hole.

[0006] Standard features of the web of a vehicle seat belt system are those specified by the National Highway Traffic Safety Administration.
lHighway Traffic Safety
Administration) Regulation 49CFR57
1.209, Standard No. 0.209; described in seat belt devices. These include breaking strength, elongation, resistance to fading and abrasion, light and microorganisms.

Known webs for vehicle seat belt systems are woven polyester or nylon fabrics. but,
Textile webs are expensive when woven to meet applicable standards and have lightweight yet flexible properties.

[0008]

SUMMARY OF THE INVENTION In accordance with the present invention, a vehicle seat belt apparatus includes a seat belt retractor having a spool, an anchor for attachment to a vehicle, and a web. The web has a length dimension, a width dimension, a first end connected to a spool, and a second end connected to another spool. The web is
It comprises an extruded elongated piece of plastic with dimensions equal to the length and width dimensions of the web.

Seat belt devices with extruded plastic webs according to the invention are manufactured by extrusion molding processes in which continuous strips are formed by extruding molten plastic material through a mold. Since long webs can be manufactured at significantly lower costs than with solid webs, it is possible to significantly reduce the cost of seat belt devices. Additionally, extruded plastic webs can weigh less than textile webs. Therefore, the strength of the spring that biases the retractor spool in the direction of pulling back the web can be reduced. A lighter spring reduces the cost and weight of the retractor and reduces the forces exerted on the vehicle occupant when the web is fastened around the occupant during normal use. Furthermore, the size and power of the motor that moves the web in a passive seat belt system can be reduced as well.

Further in accordance with the present invention, there is provided a web for a vehicle occupant seat belt apparatus that includes a web guiding component. The web has an elongated length extending across the vehicle occupant, and the cross-sectional profile allows the web to move freely through the web guiding component. The web comprises an extruded elongate piece of plastic material having the cross-sectional shape of the web and movable through the web's guiding components.

[0011] Webs according to the present invention can be formed to have a lateral stiffness that is greater than the lateral stiffness of an otherwise equivalent textile fabric material. Increased lateral stiffness increases resistance to folding or folding and ensures smooth movement of the web through the web guiding components of the seat belt device. This feature of the invention is due to the inherent stiffness of the extruded plastic material, which has a generally elliptical cross-section in the central region that is enlarged to resist lateral bending, which is not possible with reinforced or woven materials. This can be realized by forming an extrusion-molded cross-sectional shape such as a shape.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS These and other features of the invention will become apparent to those skilled in the art from reading the following description of preferred embodiments of the invention in conjunction with the accompanying drawings.

FIG. 1 shows an active seat belt device 10 comprising a seat belt web 12 according to the invention. The seat belt device 10 includes a seat belt retractor 14, an inner anchor 16, an outer anchor 18,
It further includes a D ring 20.

A clasp 22 is connected to a portion of web 12 extending from a clasp sleeve 24 at an inner anchor 16. D-ring 20 has a surface 26 that defines a guide hole in the web.
and is fixedly attached to the B-pillar 28 of the vehicle at a position adjacent to the shoulders of a seated passenger. Retractor 14 has a surface 30 defining a guide hole in the web and
and a housing having a spool 32 (FIG. 16) to which one end of the spool 2 is attached. Spool 32 is spring biased and winds web 12 onto spool 32. Web 12 may be withdrawn from spool 32 in a known manner.

Web 12 extends upwardly from spool 32 to D-ring 20 through a web guide hole defined by surface 30 and then downwardly into anchor cover 33 at outer anchor 18. A locking tongue 34 is connected to the web 12. The locking tongs 34 are
It includes a latch plate portion 36 that is locked within the clasp 22 and a surface 38 that defines a web guide hole through which the web 12 can extend and move.

When a seated vehicle occupant manually moves web 12 into the extended position shown in FIG. 1 and locks locking tongue 34 into clasp 22, web 12 unwinds from spool 32. 20 D rings each,
It slides against surfaces 26, 30, 38 defining web guide holes in retractor 14 and locking tongs 34. The pelvic restraint is thereby defined by the portion of web 12 extending from locking tongs 34 to outer anchor 18, and the upper body restraint is defined by the portion of web 12 extending from locking tongs 34 to retractor 14. . When a seated passenger unlocks the locking tongue 34 and releases it from the clasp 22, the spring-loaded spool 32 within the retractor 14 reels the web 12.
The web 12 and connected locking tongue 34 are moved outwardly of the seat belt system 10 across the seated occupant. The spring-loaded spool 32 is caused by friction between the web 12 and the surfaces defining the various web guide holes, and by the weight of the web 12, to lock the locking tongs 34.
acts to resist the load applied from the weight of the According to the invention, web 12 comprises an elongated piece of extruded plastic material. Extrusion is a manufacturing process in which a continuous piece of plastic is formed by extruding molten plastic material through a mold having the cross-sectional shape of the plastic piece to be formed. Known extrusion methods include conventional flat extrusion, pressure assisted blow tube extrusion, and drawer type "pull" techniques. Extruded webs can be formed in single or multilayer configurations, or in the form of single or multiple components. The cross-sectional shape of the web can be formed into a variety of shapes determined by the shape of the extrusion die and/or by the use of shaping rollers as the extruded material exits the extrusion die. Importantly, extruded plastic materials have a lower weight per unit length than a suitable woven material of the same dimensions and can have a smoother surface with a lower coefficient of friction than a woven material. . The light weight of web 12 allows retractor 14 to reel web 12 more easily. As required by federal regulations, the smooth surface of the web 12 allows the web 12 to easily move substantially unimpeded within the seat belt apparatus 10. Additionally, the extruded plastic web 12 does not suffer from the unraveling problems of woven webs, which is a problem under federal regulations.

Another embodiment of an extruded plastic seat belt web according to the present invention is shown in FIGS. 3-14. As shown in FIGS. 3-5, the extruded plastic web can be formed as a single piece. The web 12 shown in FIG. 3 has a rectangular cross-sectional shape that is equivalent to the generally rectangular cross-sectional shape of the prior art textile web shown in FIG. However, web 12 has a smooth plastic surface 50, unlike the somewhat rough surfaces of prior art webs that include woven threads 52. The web 54 shown in FIG. 4 has a generally rectangular cross-sectional shape with both end surfaces 56. However, the cross-sectional shape of the web 54 expands slightly to define an enlarged central region 58 which causes the outer shape of the web 54 to vary slightly from a rectangular shape into a somewhat oval shape. The enlarged central region 58 is the web 54
, thereby providing web 54 with a degree of lateral stiffness that is greater than the lateral stiffness of a similar web having a rectangular cross-sectional profile. The web 60 shown in FIG. 5 has a similarly enlarged central region 62.
, but has opposite edge surfaces 64 that are slightly curved to give the web 60 an overall more oval cross-sectional shape.

The web 66 shown in FIG. 6 may also be formed as a single piece of extruded plastic material;
It has a cross-sectional profile with an enlarged edge portion 68 that provides greater stiffness to the cross-sectional area.

A further alternative web 70 is shown in FIG. The web 70 includes a pair of walls 74 on either side of the lateral surface 72.
, 76 is formed as an elongated tubular member. The walls 74 , 76 are adjacent across a central region 78 of the web 70 and are spaced apart at opposite edge portions 80 of the web 70 to define a circular inner edge space 82 . Metal reinforced wire 8
4 extend within the edge space 82 to increase the longitudinal stiffness of the edge portion 80. Alternatively, the extruded plastic web 92 may have a generally elliptical edge spacing 92 as shown in FIG. An edge space 96 may also be provided. The separate extruded plastic webs 90, 94 may also be provided with internal reinforcement.

As shown in FIG. 10, another extruded plastic web 100 has sidewalls 1 slightly spaced apart.
02, 104 as a flat tubular member. The web 106 shown in FIG. 11 is similarly shaped as a flat tubular member having adjacent sidewalls 108, 110. As shown in FIG. 12, an extruded plastic web 112 is formed into a concentric pair of flat tubular members 114, 116.
13, the extruded plastic web 118 includes a flat member 120 extending longitudinally within a flat tubular member 122. As shown in FIG.

[0021] The web according to the invention can be provided with a surface treatment. As shown in FIG. 11, web 106 has an embossed surface 130. As shown in FIG. 14, web 136 has flocked surface material 140 on its outer surface.

The alternate embodiments of seat belt web 12 illustrated can each be manufactured in accordance with standards set forth in federal regulations. For example, standard No. 209; Seat Belt Devices, 49 CFR 571.209, the web according to the present invention has a width dimension not less than 45.72 mm (1.8 inches). When used as a lap belt in a pelvic restraint, the web according to the invention
Has a breaking strength not less than 4 kg (6000 lbs). When used as a combination pelvic and upper body restraint, the web according to the invention has a
not less than 67.95 kg (5000 lbs) and 1814.36 kg (4000 lbs) for upper body restraints.
s) have a breaking strength not less than or equal to: The pelvic restraint is 113
Manufactured to stretch at 2500 lbs without stretching more than 20%. The combination of pelvis and upper body restraint is 1133 in the pelvis restraint part.
．． 975 kg (2500 lbs), not more than 30%, but 1133.975 kg (2500 lbs) at the upper body restraint part
lbs) without stretching more than 40%.

FIG. 16 schematically shows the direct connection between the web 12 of the embodiment shown in FIG. 3 and the spool 32 of the retractor 14. Spool 32 is axis line 15
It is supported within the retractor 14 so as to be rotatable about zero. Inner wall surfaces 152, 154 of spool 32 define a slot extending diametrically through spool 32. The slot includes a first slot portion 156 and a relatively narrow second slot portion 158. The ends of web 12 extend about retainer pins 160 and are held in place between overlapping surfaces 162, 164 of web 12 by adhesive. Retainer pin 160
is received within the first slot portion 156 , the web 12 extends from the retainer pin 160 through the second slot portion 158 and along the spool 32 . When the web 12 is fully unwound from the spool 32, the relatively narrow dimensions of the second slot portion 158 prevent the retainer pin 160 from being withdrawn through the slot. This holds the ends of the web 12 and does not pull them out of the spool 32. The other end of the web 12 can similarly be connected directly to the anchor by extending the web 12 in a loop through the hole in the anchor and by adhering the overlapping surfaces of the web 12 together.

Referring now to FIG. 2, a passive seat belt device 200 having an extruded plastic web 202 according to yet another embodiment of the present invention is schematically illustrated. The passive seat belt device 200 includes an elongated track 2
04 and a sliding anchor 206 that can move along the track 204. A flexible tape or wire 208 is connected to sliding anchor 206. The tape 2
08 is driven by motor 210 to move through track 204 to move sliding anchor 206 back and forth between a forward position shown in dashed lines and a rearward position shown in solid lines.

Passive seat belt system 200 also includes a retractor 212. The retractor 212 includes a surface 214 that defines a web guide hole and a spool that is spring driven in a conventional manner.

The web 202 has one end connected to a retractor 212.
spool, while the other end is connected to a sliding anchor 206. The sliding anchor 206 is the motor 21
0 between a forward position and a rearward position, the web 202 is moved between an open position, where the web 202 moves away from a seated vehicle occupant, and a closed position, where the web 202 wraps around the seated vehicle occupant. move between positions. The weight of web 202 loads the motor 212 and also loads the spring that drives the retractor spool. According to the invention, web 202 comprises an elongated piece of extruded plastic material. The weight of the web 202 is less than the weight of an equivalent piece of woven fabric material, thus
Reduces the load on the motor 210 and retractor spring. Although the invention has been described in terms of a preferred embodiment, modifications and adaptations will become apparent to those skilled in the art upon reading the specification. All such modifications and adaptations are intended to be covered by the following claims.

[Brief explanation of the drawing]

1 is a schematic illustration of an active vehicle seat belt device comprising a web according to the invention; FIG.

FIG. 2 is a schematic illustration of a passive vehicle seat belt device comprising a web according to the invention;

FIG. 3 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 4 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 5 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 6 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 7 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 8 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 9 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 10 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 11 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 12 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 13 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 14 is a cross-sectional view of one embodiment of a web according to the invention.

FIG. 15 is a cross-sectional view of a prior art web of a vehicle seat belt device.

FIG. 16 is a schematic illustration of a component assembly of a vehicle seat belt device according to the invention;

[Explanation of symbols]

10 Seat belt device 1
2 Web 14 Retractor
16 Inner anchor 18 Outer anchor
20 D ring 22 Clasp
24 Clasp sleeve 28 B pillar
32 Spool 33 Anchor cover
34 Locking tongs

Claims (23)

[Claims] 1. A seat belt device for a vehicle, comprising: a seat belt retractor having a spool; an anchor attached to the vehicle; and a second end connected to the anchor, the web comprising an extruded elongated piece of plastic material having the length and width dimensions. belt device. 2. The vehicle seat belt system of claim 1, wherein said extruded elongate piece of plastic material has a rectangular cross-sectional profile. 3. The vehicle seat belt apparatus of claim 2, further comprising an elongate track, the anchor being movable along the track, and further associated with the anchor, the anchor being movable along the track. A vehicle seat belt device characterized by comprising a motor that moves along a track. 4. The vehicle seat belt device according to claim 2, wherein the anchor is attached to the vehicle at a predetermined position. 5. A web of a vehicle occupant seat belt apparatus comprising a web guiding component, an elongated length extending across the vehicle occupant and movable through the web guiding component. A web having a cross-sectional profile and comprising an extruded elongated piece of plastic material having said cross-sectional profile. 6. The web of claim 5, wherein the extruded elongate piece of plastic material has a non-rectangular cross-sectional profile. 7. The web of claim 6, wherein the extruded elongated piece of plastic material has an end portion connectable to a spool in a seat belt retractor. 8. The web of claim 7, wherein said extruded elongate piece of plastic material has a pair of walls on opposite sides of a plane perpendicular to said tubular member, and a central region adjacent said walls. A web characterized in that said wall comprises an elongated tubular member of cross-sectional shape having two opposite edges that are separated and define an inner edge space of said web. 9. The web according to claim 8, wherein the edge space has a generally elliptical cross-sectional shape. 10. The web according to claim 8, wherein the edge space has a substantially rectangular cross-sectional shape. 11. The web according to claim 8, wherein the edge space has a substantially circular cross-sectional shape. 12. The web of claim 8 further comprising an elongate edge reinforcement member extending within the edge space. 13. The web according to claim 12,
A web characterized in that the edge reinforcement member is a flexible metal wire. 14. The web according to claim 13,
A web comprising a plurality of flexible metal wires extending within each edge space. 15. The web of claim 7, wherein the extruded elongate piece of plastic material further comprises an outer tubular member and a flat extruded plastic member extending within the outer tubular member. A web featuring. 16. The web of claim 7, wherein the extruded elongate piece of plastic material comprises an elongate outer tubular member and an extruded elongate inner tubular member extending within the outer tubular member. A web further comprising: 17. The web of claim 7, wherein the extruded elongated piece of plastic material comprises an elongated tubular member having an embossed outer surface. 18. The web of claim 7, wherein the extruded elongate piece of plastic material comprises an elongate tubular member having a flocked outer surface. 19. The web of claim 5, wherein the extruded elongated piece of plastic material comprises a pelvic restraint portion, the pelvic restraint portion having a diameter of 45.72 mm (1 mm).
．． 8 inches). 20. The web according to claim 19,
The pelvic restraint portion of the extruded elongated piece of plastic material weighs 6,000 lb
s) A web characterized in that it has a breaking strength not less than or equal to: 21. The web according to claim 20,
The pelvic restraint portion of the extruded elongated plastic material weighs 2,500 lb
A web characterized in that it is not stretched by more than 20% in s). 22. The web of claim 5, wherein the extruded elongated piece of plastic material comprises a pelvic restraint portion and an upper body restraint portion, the pelvic restraint portion having a weight of 5,000 kg (2267.95 kg). lbs), and the upper body restraining portion has a breaking strength of not less than 1814.lbs.
A web having a breaking strength of no more than 4,000 lbs. 23. The web according to claim 22,
The pelvic restraint portion of the extruded elongated piece of plastic material weighs 2,500 l.
bs) without stretching more than 30%, and the upper body restraint part is 1133.975 kg (2,500 lbs) and 40%
A web characterized by not being stretched by more than %.