GB2134772A - Anchorage for vehicle safety belts - Google Patents

Abstract

An adjustable shoulder anchorage assembly comprises a traveller 24 mounted on a vertically extending track 10. A slotted member 34 is pivotally mounted on the traveller for angular movement about a horizontal axis and has a slot 36 for receiving a strap of a safety belt. The traveller 24 carries a spring-loaded plunger 46 arranged to engage with detent formations 20 on the track 10. The slotted member 34 has a cam formation 38 arranged to prevent disengagement of the locking member 46 when the slotted member 34 is pivoted forwardly to its position of normal use. <IMAGE>

Description

SPECIFICATION Anchorage means for vehicle safety belts This invention relates to anchorage means for vehicle safety belts and more particularly to anchorage means of the kind which are adapted to be mounted on a vehicle body above the shoulder level of the occupant of an adjacent seat for reception of the shoulder strap of the safety belt.

The present invention is particularly concerned with the provision of a shoulder anchorage of adjustable height.

Many proposals for adjustable shoulder anchorages have been made. For example Patent Specification GB-A-2081568 discloses an adjustable shoulder anchorage in which a traveller is slidable along a vertical track and carries a spring-loaded plunger which can move into engagement with notches in the track to lock the shoulder anchorage in a desired position. The plunger can be disengaged by a slidable camming member. The present invention is concerned with an adjustable shoulder anchorage of this type in which the locking member is restrained against disengagement when the safety belt is in normal use.

According to the invention, an adjustable shoulder anchorage assembly comprises a vertically extending track mounted on the interior of a vehicle body above the level of the shoulders of an occupant of an adjacent seat, a traveller mounted on the track and a slotted member pivotally mounted on the traveller for angular movement about a horizontal axis extending transversely on the vehicle and having a slot for receiving a strap of a safety belt extending tangentially to said pivot axis, the traveller having manually disengageable spring-loaded locking means arranged to engage with detent formations on the track and the slotted member having a blocking formation arranged to prevent disengagement of the locking member when the slotted member is pivoted forwardly relative to the vehicle from the position in which the slot is horizontal and below the pivot axis.

The invention thus takes advantage of the fact that, in normal use, a shoulder anchorage is pulled forwardly by the strap which is attached to it, while it hangs vertically when not in use.

The locking member can conveniently take the form of a spring-loaded plunger movable in a direction parallel to the pivot axis and biased into engagement with one of a row of apertures in the track. The track itself may conveniently take the form of a vertically extending slot in the vehicle body, the holes for the locking means being disposed adjacent to the slot.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a perspective view of part of the B-post of a motor vehicle provided with a track for an adjustable shoulder anchorage assembly in accordance with the invention: Figure 2 is a partially broken away elevation view of the traveller and slotted member of a shoulder anchorage assembly for use with the track shown in Figure 1; Figure 3 is a perspective view of the slotted member of Figure 2; Figure 4 is a cross-sectional view taken on the line 4-4 of Figure 2 and also showing the track, with the locking member with its slot horizontal; Figure 5 is a cross-sectional view similar to Figure 4 but with the slotted member pivoted forwardly; and Figure 6 is a cross-sectional view similar to Figures 4 and 5 but with the slot horizontal and the locking member disengaged.

Figure 1 shows part of the right-hand-side B-post 10 of a motor car which, as can be seen, is formed from two channel sections welded together. The channel section 12 faces the interior of the vehicle and the edge 14 faces forwardly. A key-hole slot 1 6 extends vertically in the channel section 1 2 with its circular aperture 1 8 at the upper end. A row of holes 20 extends parallel to the slot 1 6 on the side thereof nearer to the front of the vehicle. A reinforcing plate 22 is welded to the interior of the channel section and has compiementary openings aligned with the slot 1 6 and the holes 20.

Turning now to Figures 2, 3 and 4, the movable part of the shoulder anchorage comprises a traveller 24 which is of inverted L-shape in elevation. At the bottom of its vertical limb, the traveller 24 carries a bolt 26, the head 28 of which is of smaller diameter than the hole 18 at the top of the slot 1 6. Adjacent to its head 28, the bolt 26 has a shank portion 30 of square crosssection dimensioned to be a sliding fit in the slot 1 6 while inhibiting angular movement of the bolt 26 relative thereto.The portion of the bolt 26 which extends through the traveller 24 is also of square cross-section with the result that the traveller 24 is held in a predetermined orientation relative to the slot 1 6. Pivotally mounted on the bolt 26, and spaced from the traveller 24 by a washer 32, is a slotted member 34 having an elongate slot 36 for receiving the strap of a safety belt. The slotted member 34 has an arcuate limb 38 extending from its front edge in an arc of a circle centred on the axis of the slot 26. The tip of the limb 38 is of reduced thickness compared with the rest of the slotted member 34.

The horizontal limb of the traveller 24 carries a flange 42 the end 44 of which is bent over so as to lie parallel to the main part of the traveller 24. A plunger 46 is slidable in holes in the portion 44 and the main part of the traveller 24 into an out of engagement with the holes 20 in the B-post 10.

The plunger 46 has a flange 48 at an intermediate position along its length and a spring 50 engages with the flange 48 to bias the plunger 46 towards the B-post 10.

The arcuate limb 38 of the slotted member 34 extends into close proximity with the plunger 46 and lies in the path of the flange 48.

Engaging between the flange 48 and the main body of the traveller 24 is a slidable camming member 52 having ramps 54 and 56 which engage under the flange 48. The end face 58 of the camming member 52 comprises a manually depressable push button.

When the slotted member 34 is located with its slot 36 horizontal, as illustrated in Figure 4, the slidable member 52 can be depressed so that the ramps 54 and 56 thereof engage with the flange 48 to displace the plunger 46 to the left, as viewed in Figures 4 to 6, thereby moving it from the position illustrated in Figure 4 to the position illustrated in Figure 6 in which it is disengaged from the holes 20 and the traveller 24 is free to slide along the slot 1 6. Under these circumstances the flange 48 is aligned with the reduced thickness portion 40 of the arcuate limb 38 and consequently its movement is not obstructed. The traveller can therefore be slid to any desired height.

On the other hand, if the slotted member 34 swings forwardly from the position illustrated in Figure 4 to the position illustrated in Figure 5, as would take place when the seat belt is fastened round a user's body, the shoulder 60 at the beginning of the full thickness part of the arcuate limb 38 moves into the path of the flange 48, inhibiting outward movement thereof so that the plunger 46 remains locked in its engaged position and the push button 58 cannot be depressed.

Conversely, if an attempt is made to put on the safety belt while the plunger 46 is in its disengaged position, as illustrated in Figure 6, the shoulder 60 will abut against the flange 48 and prevent the slotted member 34 from swinging forwardly. The resulting downward pull on the slotted member 34 will tend to move the traveller 24 to bring the plunger into alignment with the next lower hole 20, the top edges of which are provided with downward leads 62 to facilitate such engagement.

The invention accordingly provides an adjustable shoulder anchorage which cannot be inadvertently disengaged in normal use and in which deployment of the safety belt is partially inhibited if such deployment is attempted when the shoulder anchorage is not in one of its locked positions.

Claims (6)

1. An adjustable shoulder anchorage assembly comprising a vertically extending track mounted on the interior of a vehicle body above the level of the shoulders of an occupant of an adjacent seat, a traveller mounted on the track and a slotted member pivotally mounted on the traveller for angular movement about a horizontal axis extending transversely on the vehicle and having a slot for receiving a strap of a safety belt extending tangentially to said pivot axis, the traveller having manually disengageable spring-loaded locking means arranged to engage with detent formations on the track and the slotted member having a blocking formation arranged to prevent disengagement of the locking member when the slotted member is pivoted forwardly relative to the vehicle from the position in which the slot is horizontal and below the pivot axis.

2. A shoulder anchorage assembly according to claim 1, wherein the track comprises a vertically extending slot in the vehicle body and the locking means comprise a series of holes disposed adjacent to the slot.

3. A shoulder anchorage assembly according to claim 1 or 3, wherein the locking member comprises a spring-loaded plunger movable in a direction parallel to the pivot axis and biased into engagement with one of a row of apertures in the track.

4. A shoulder anchorage assembly according to claim 2, wherein the plunger has a flange formed thereon one side of which is engaged by the blocking means.

5. A shoulder anchorage assembly according to claim 4, further comprising manually operable camming member arranged to engage with the other side of the flange on the plunger to displace it out of engagement with the track.

6. An adjustable shoulder anchorage assembly substantially as hereinbefore described with reference to the accompanying drawings.