GB2189377A - Improvements in or relating to a safety belt guide - Google Patents

Abstract

A guide (1) for a safety belt consists of an elongate member over which the belt passes, mounted on a nut (9) which, in turn, is rotatably mounted on a threaded stud (8) for rotation about one axis. The stud is rotatably mounted on a bolt (4) for rotation about a second axis. The elongate member may be a roller passing through two apertured plates and supported for rotation by yieldable low friction bearings. When a significant force is applied to the safety belt the elongate member is brought into contact with the walls of the apertures in the apertured plates. <IMAGE>

Description

SPECIFICATION Improvements in or relating to a safety belt guide The present invention relates to a safety belt guide suitable for use with a safety belt as used in a motor vehicle such as a car. More particularly the invention relates to a safety belt guide adapted to be located adjacent the shoulder of a person wearing a safety belt and to guide the safety belt in a region between a portion of the safety belt extending downwardly from the guide towards the retractor reel and a portion of the belt extending downwardly from the guide across the chest of a person wearing the safety belt.

It is common practice to provide a guide for a safety belt on the "B" post of a motor vehicle in a position adjacent the shoulder of a person occupying the front seat of the motor vehicle. A retractor reel for the safety belt is located on the floor of the motor vehicle at the base of the "B" post and the safety belt extends upwardly from the retractor reel through the guide and can then be positioned extending across the chest of the person occupying the front seat of the motor vehicle. It is preferred that the guide should offer the minimum of friction or other resistance to movement of the belt through the guide, since otherwise an overlarge force has to be applied to the belt to withdraw the belt from the retractor reel and position the belt across the chest of a person wearing the belt.

Nevertheless, whilst there is a requirement for the guide to offer a minimum of friction or other resistance to movement of the safety belt through the guide, the guide must be able to withstand the considerable force that is applied to the guide during braking conditions and during accident conditions.

Whilst the guide should be capable of being positioned to minimise the resistance to movement of the belt caused by the passage of the beit through the guide, the guide should not be able to move away from the "B" post to any significant extent, since otherwise the part of the belt extending from the retractor reel to the guide will not be in its intended place and may thus snag or rub against projections or the like, which is clearly undesirable since it may cause the belt to break under accident conditions.

According to one aspect of this invention there is provided a guide for guiding a seat belt, said guide comprising a roller, means for supporting the roller including two spaced-apart plates, each plate having an aperture therein with a diameter greater than the diameter of the roller, the roller passing through the apertures, the roller being supported in low friction bearings at positions beyond said plates.

Preferably each low friction bearing is constituted by part of a snap-on cover.

Conveniently the ends of the rollers are provided with trunions, each trunion being received in a recess formed in said snap-on cover.

Advantageously the or each cover is formed of low friction or self lubricating plastics material.

Preferably said plates form part of a roller support element, the roller support element being adapted for rotation, as a whole, about a first axis, and also for rotation about a second transverse axis.

Conveniently the roller can rotate about its own axis, and can rotate about said first axis and said second axis, but cannot move about any other axis.

Preferably said covers are formed integrally.

According to another aspect of this invention there is provided a guide for a safety belt or the like, said guide comprising an elongate member over which the belt may pass, the elongate member being mounted on a nut, said nut being rotatably mounted on a threaded stud for rotation about one axis, the threaded stud itself being rotatably mounted on a bolt for rotation about a second axis which is perpendicular to said one axis, the bolt being adapted to mount the guide in position on a motor vehicle or the like.

Conveniently the elongate member is mounted on the nut by means of a support element, the support element having a plate-like portion welded to one face of the nut, there being two wings at the ends of the plate-like portion extending perpendicularly thereto, the elongate member being supported on said wings.

Preferably the elongate member is in the form of a rotatable roller. Preferably the roller passes through an aperture formed in each of said wings, each aperture having a diameter greater than the diameter of the roller, the roller being rotatably mounted on a low friction bearing at a position beyond each of said wings.

Conveniently each low friction bearing is constituted by part of a snap-on cover.

Advantageously each end of the roller is provided with a trunion received within a recess defined in said snap-on cover, and preferably said cover is formed of a low friction or self lubricating plastics material.

Conveniently the threaded stud is formed with a ring constituting an extension thereof, the securing bolt passing the ring so that the threaded stud is mounted for rotation about said second axis.

-P-referably the securing bolt is provided with a collar thereon arranged so that when the bolt is tightened, the described components of the guide are at a position remote from the surface to which the bolt is secured.

Conveniently the said stud is rotatable in a single plane so that at least one point on said elongate member remains in a predetermined plane.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure lisa front view of a guide in accordance with the invention; Figure 2 is a part vertical sectional and part cutaway view of the guide of Figure 1; Figure 3 is a perspective view of two of the components of the guide shown in Figure 1; and Figure 4 is a diagrammatic cross-sectional view of part of the guide of Figure 1 showing one end of the roller (the other end of the roller corresponds).

Referring initially to Figures 1 and 2 a guide 1 in accordance with the present invention is adapted to be secured to the "B" post of a motor vehicle by means of a horizontal bolt 2 which has a hexagonal head 3 and a threaded shank 4. A washer 5 is located on the bolt, which is located adjacent the head, and a ring plate 6 is subsequently mounted on the bolt.

Finally a collar 7 is mounted on the bolts and when the bolt is secured to a nut or the like welded to the interior of the "B" post the ring 6 is spaced from the "B" post. The ring 6 may rotate about the bolt, but if the bolt is correctly tightened, the ring cannot move or tilt to any significant extent out of the plane defined by the ring.

The ring 6 is a planar extension of a threaded stud 8. When the guide is in position, by virtue of the design of the ring 6 the threaded stud8 may rotate about the axis defined by the bolt 2. The threaded stud 8 is illustrated in its normal rest position, which is vertical.

A hexagonal nut 9 is threadedly mounted on the threaded stud 8 and a roller support 10 (which is illustrated more clearly in Figure 3) is welded to the front face of the nut 9. Since the nut 9 can rotate about the vertical axis of the threaded stud 8 it will be appreciated that the roller holder 10 can rotate about two axes, firstly about the horizontal axis defined by the bolt 2 and secondly about the vertical axis defined by the threaded stud 8. Thus the roller holder 10 can position itself in virtually any orientation, although by virtue of the design of the ring 6, and the fact that the roller is connected to the ring 6 by means of the stud-and-bolt connection mentioned above, it is to be noted that the centre point of the roller holder will not leave the plane defined by the ring 6.Thus the portion of the belt extending from the retractor reel to the guide 1 will always extend in the same direction. Thus, in contrast to certain prior proposed guides in which a roller holder may move forwardly from its initial plane, (thus permitting the belt to snag on the outlet mouth of the retractor reel) in the present invention the vertical portion of the belt will always follow substantially the same path, thus minimising the risk of any snags.

As can be seen most clearly in Figure 3 the roller holder 10 consists of a transverse plate 11, which is the part of the holder secured to the nut 9, the transverse plate terminting in two rearwardly directed wings 12. Each wing 12 has a depending portion 13 defining a circular aperture 14 therein.

The roller 15 is provided which extends through the two apertures 14 in the depending portions 13. Each aperture 14 has a greater diameter than the diameter of the roller 15.

At the ends of the roller 15 are trunions 16.

As can be seen in Figure 4the illustrated end of the roller is actually pivotally supported on the trunion 16 which is received in a correspondingly dimensioned recess 18 in a spigot 19 formed on the interior of a snap-on cap 20 which may be made of an appropriate plastics material, such as a low friction of "self lubricating" plastic such asthat sold under the designation "Nylon 66'. The snap-on cap 20 is adapted to be snapped-fastened, in some way, to the roll holder as illustrated in Figure 3 and when snap fastened in position the trunion 16 is received in the recess 18-which constitutes a low friction bearing for the roller 15. A single snap-on cap may be provided which defines bearings for both ends of the roller.When the roller is supported by the bearings, whilst the roller is free to rotate the roller cannot move, to any significant extent, in the axial direction. Also the bearings will not permit any significant movement in the radial direction, at least until a significant radial or tangential force is applied to the roller as will be described below.

As will be appreciated in use of the described guide a portion of seat belt is passed over the roller 15. If the seat belt is withdrawn or retracted from the retractor reel over the guide the roller will rotate about the low friction bearings constituted by the trunions 16 and the recesses 18. 1-lowever, if the seat belt is subjected to an excessive force, for example under braking conditions or in an accident situation, the belt will apply a signfficant radial or tangential force to the roller, the plastic cap 20 will yield slightly resiliently, and then the portions of the roller 15 extending through the apertures 44 will come into direct contact with 4hue side walls of the apertures-i4form; ;ed inthe projections 13 oqthe wings 12. The force applied to the roller is thus directly transferred to the roll holder. Thus the described guide is able to withstand any severe force appli d to It by the belt, even though the roller rotates on a very low friction bearing in normal use of the arrangement.

Whilst the guide has been described as being mounted on the "B" post of a motor vehicle, it may be located in other positions, for example adjacent the rear seat of a motor car.

Claims (1)

1. A guide for guiding a seat belt, said guide comprising a roller, -means for supporting the roller including two spaced-apart plates, each plate having an aperture therein with a diameter greater than the diameter of the roller, the roller passing through the apertures, the roller being supported in low friction bearings at positions beyond said plates.

2. A guide according to claim 1,wherein each low friction bearing is Constituted by part of a snap-on cover.

3. A guide according to claim 2, wherein theerids of the rollers are provided with trunions, each trunion being received in a recess formed in said snap-on cover.

4. A guide according to claim 2 or claim 3, wherein the or each cover is formed of low friction or self lubricating plastics material.

5. A guide according to any one of claims 1 to 3, wherein sad plates forms part of a roller support element, the roller support element being adapted for rotation, as a whale, about a first axis, and also for rotation aboute second transverse axis.

6. A guide according tb claim 5, wherein the roller can rotate aboufits own axis, and can rotate about said first axis and said second axis, but cannot move about any otheraxis.

7. Aseat belt guide according to any one of claims t to 6, wherein said covers are formed integrally.

8. A guide for a safety belt or the like, said guide comprising an elongate member over which the belt may pass, the elongate member being mounted on a nut, said nut being rotatably mounted on a threaded stud for rotation about one axis, the threaded stud itself being rotatably mounted on a bolt for rotation about a second axis which is perpendicular to said one axis, the bolt being adapted to mount the guide in position oh a motor vehicle or the like.

9. A guide according to claim 1,wherein the elongate member is mounted on the nut by means of a support element, the support element having a plate-like portion welded to one face ofthe-nut, there being two wings at the ends of the plate-like portion extending perpendicularly thereto, the elongate member being supported on said wings..

10. A guide according to claim 8 or 9, wherein the elongate member is in the form of a rotatable roller.

tl. A seat belt guide according to claim 10 as dependent upon claim 9, wherein the roller passes through an aperture formed in eachof said wings, each aperture having a diameter greater than the diameter of the roller, the roller being rotatably mounted on a ìow frietion bearing at a position beyond each of said wings.

12. A seat belt guide according to claim 11, wherein each low friction bearing is constituted by part of a snap-on cover.

13, A guide according to claim 12, wherein each end of the roller is provided with a trunion received within-a recessdefined in said snap-on cover, 14, A guide according to claim 12 or 13, wherein said cover is formed of a low friction or self lubricating plastics material.

15. A guide according to any one of claims 8 to 14, wherein the threaded stud is formed with a ring constituting an extension thereof, the securing bolt passing through the ring so thatthethreaded stud is mounted for rotation about said second axis.

16. A guide according to any one of claims 8 to 15, wherein the securing bolt is provided with a collar thereon arranged so that when the bolt is tightened, the described components of the guide are at a position remote from the surface which.the bolt is secured.

17. A guide according to any one of claims 8 to 16, wherein the said stud is rotatable in a single plane so that at least one point on said elongate member remains in a predetermined plane.

18. A seat belt guide substantially as herein described with reference to and as shown in the accompanying drawings.

19. Any novetfeature or combination of features diselosed herein.