ANCHORAGE SYSTEMS

Abstract

An anchorage system includes an elongate track defining an interior channel and an anchorage device securable at any of plural longitudinal positions on the track. The track has a base and first and second sides. A longitudinal channel opening opens in an outward face of the track and is defined between first and second retaining flanges at the outward face. The flanges project in towards one another and overlay the interior channel. The flanges have edge faces directed laterally towards one another across the channel opening and outward surfaces which are comprised in the outward face of the track. The anchorage device has a body, a retaining foot and a stem portion connecting the body and the retaining foot. The foot is laterally wider than the stem portion, and the anchorage device is engageable in the track with the foot in the interior channel.

Claims

1. Anchorage system comprising an elongate track defining an interior channel and an anchorage device securable at any of plural longitudinal positions on the track; the track comprising a base and having first and second sides, a longitudinal channel opening which opens in an outward face of the track and is defined between first and second retaining flanges at the outward face, the flanges projecting in towards one another and overlying the interior channel, the flanges having edge faces directed laterally towards one another across the channel opening and outward surfaces which are comprised in the outward face of the track; the interior channel being defined by an outwardly-directed surface of the base, laterally inwardly-facing side wall surfaces defining lateral extremities of the channel, and by inwardly-directed faces of the retaining flanges directed towards the base; the anchorage device comprising a body, at least one retaining foot and a stem portion connecting the body and the at least one retaining foot, the foot being laterally wider than the stem portion and the anchorage device being engageable in the track with the foot in the interior channel, the stem portion extending through the channel opening between the retaining flanges and the body outside the track with an inward face of the body overlying the outward face of the track; the anchorage device being tiltable relative to the track around a longitudinal axis, under lateral load applied to the body of the anchorage device, to a tilted position at which tilt is limited by engagement of an outward face of the foot at the first side of the track with the inward face of the first retaining flange at respective contact regions of the foot and flange, and/or by engagement of an undersurface of the device body at the second side of the track against the outward face of the track, or by engagement of an inward face of the foot against the outwardly-directed surface of the base of the track, and wherein the inward face of the retaining flange at the contact region is not angled outwards in the direction towards the median line of the channel, or is angled outwards at an angle of less than 10°.

2. Anchorage system of claim 1 in which the inward face of the retaining flange at the contact region is angled outwards at an angle of less than 5°.

3. Anchorage system of claim 1, wherein: the inward face of the retaining flange comprises distinct lateral sub-regions; one or more of the sub-regions comprising the outward angle.

4. Anchorage system of claim 1, wherein the outward face of the foot at the first side has one or more angles and form features in cross-sectional shape generally complementing those of the inward face of the retaining flange, at least at the contact region.

5. Anchorage system of claim 1, wherein the outward face of the foot at the first side has an inward angle of the foot outward surface relative to the track plane less than 10°, over the contact region or over one or more sub-regions thereof.

6. Anchorage system of claim 1, wherein the inward face of the retaining flange is stepped in form, in transverse cross-section.

7. Anchorage system of claim 6 in which the outward face of the foot at the first side is also stepped in form in transverse cross-section, the direction(s) of the step(s) complementing that/those of the inward face of the retaining flange.

8. Anchorage system of claim 7 in which the contact region of the inward face of the retaining flange comprises a laterally outer sub-region and a laterally inner sub-region with a step between them, and the contact region of the outward face of the foot comprises a laterally outer sub-region and a laterally inner sub-region with a step between them complementary to that of the flange, whereby the respective laterally outer sub-regions and the respective laterally inner sub-regions of the flange and foot are contactable against one another.

9. Anchorage system of claim 8 in which the directions of the steps are such that the laterally outer sub-regions of the flange and foot are positioned outwardly in the system relative to the respective inner regions.

10. Anchorage system of claim 8 in which the directions of the steps are such that the laterally outer sub-regions of the flange and foot are positioned inwardly in the system relative to the respective inner regions.

11. Anchorage system of claim 8 in which for one or more of the sub-regions, any outward angle in the direction towards the median line of the channel is less than 5°.

12. Anchorage system of claim 1, wherein the lateral tilt angle in the tilted position, without deformation of the track or foot, is 4° or less relative to the non-tilted position.

13. Anchorage system of claim 1, comprising mutually inter-engaging formations on the underside of the device body at the second side, and on the outward face of the track at the second side, which engage one another in the tilted position to resist lateral movement of the device body relative to the track.

14. Anchorage system of claim 13 in which the mutually inter-engaging formations comprise an inward protrusion on the device body undersurface and a recess of the outward track face, such as at an indentation, groove or shoulder, which the inward protrusion engages in the tilted position.

15. Anchorage system of claim 1, wherein the anchorage device, or at least a portion thereof having the at least one foot and stem portion, is a machined or cast component.

16. Anchorage system of claim 1, wherein at least the track is symmetrical about the median plane with the first and second sides similarly formed.

17. A track for an anchorage system, comprising: a base; first and second sides; a longitudinal channel opening which opens in an outward face of the track and is defined between first and second retaining flanges at the outward face; wherein, the flanges project inwardly towards one another and overlay the interior channel; wherein, the flanges comprise edge faces directed laterally towards one another across the channel opening and outward surfaces which are comprised in the outward face of the track; wherein, an interior channel is defined by an outwardly-directed surface of the base, laterally inwardly-facing side wall surfaces defining lateral extremities of the channel, and inwardly-directed faces of the retaining flanges directed towards the base.

18. The track of claim 17, wherein the inward face of the retaining flange at the contact region is angled outwards at an angle of less than 5°.

19. The track of claim 17, wherein: the inward face of the retaining flange comprises distinct lateral sub-regions; one or more of the sub-regions comprising the outward angle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Examples are now described, with reference to the accompanying drawings in which:

[0032] FIG. 1 is a perspective view of a known type of anchorage system, showing an anchorage device fitted into a segment of conventional track;

[0033] FIG. 2 shows the FIG. 1 anchorage device in more detail;

[0034] FIG. 3 shows the conventional track segment alone;

[0035] FIG. 4 is a transverse cross-section showing the conventional device at a tilted position in the track, resulting from a lateral load of the device;

[0036] FIG. 5 is a perspective view, corresponding to FIG. 1, of a first embodiment of anchorage system embodying our proposals;

[0037] FIG. 6 shows the anchorage device of the first embodiment, omitting a locking plunger;

[0038] FIG. 7 shows the track of the first embodiment;

[0039] FIG. 8 shows the anchorage system of the first embodiment with the anchorage device in a tilted position under lateral load;

[0040] FIG. 9 shows an anchorage system of a second embodiment;

[0041] FIG. 10 shows the anchorage device of the second embodiment, with a plunger omitted;

[0042] FIG. 11 shows the track of the second embodiment; and

[0043] FIG. 12 is a transverse cross-section showing the anchorage system of the second embodiment in the tilted position of the anchorage device.

DETAILED DESCRIPTION

[0044] FIGS. 1-4 show a prior art system. An anchorage device 2 is fitted releasably to a track 1. The track is a one-piece metal channel member having a base 11, side walls 12, a channel interior 10 defined between the side walls 12 and above the base 11, retaining flanges 14 extending inwardly above the channel interior 10 from the tops of the side walls and defining between them a channel opening 101 extending along the median line of the track, and outward flanges 15 extending outwardly from the tops of the side walls. The track 1 is designed to be mounted in an elongate slot or groove in e.g., a floor, wall or ceiling of a vehicle, with the base recessed and the undersides of the flanges 15 lying against the support surface. The track has an outward face 16 including the inclined tops of the flanges 15 and a single flat face above the side walls 12 and including the outward surfaces 143 of the inward flanges 14. The outward track face 16 is interrupted by the central channel opening 101, which also features a periodic series of circular cut-outs 17 in the well-known way so that the mutually-opposed surfaces of the first and second retaining flanges 14 are partly flat edge faces 142 and partly arcuate cut-out surfaces with shoulder regions 171 towards their ends. The track 1 is an aluminum extrusion. The cut-outs may be formed by drilling, as is known. A skilled person is aware that tracks of this general kind may be made with various forms, and in particular the disposition of mounting flanges may be different from that shown here depending on the intended mounting position.

[0045] The anchorage device 2 has a main body 20 carrying four generally circular feet 21 connected to the body by a stem portion or keel 22. In this embodiment the anchorage device 2 is itself non-functional beyond its anchorage function, but has a mounting 25 for an associated component, e.g., a seatbelt mount or the like. In this embodiment the feet 21 are cast in one piece with the keel 22 and body 20. The feet are sized and spaced so that they can fit down in a corresponding series of the track cut-outs 17. A plunger 24 with a grip 241 exposed at the top of the body 20 is mounted vertically and slidably in the body, so that it can be lifted against a spring bias which urges it downwards to the position of FIG. 2. The plunger 24 is half-way between two feet 21. With lifting of the plunger 24 against the spring, the device 2 can be inserted into the track through respective cut-outs thereof and then slid along half a space allowing the plunger 24 to drop into a cut-out and lock it in place, and bringing longitudinally-directed shoulder formations 23, formed integrally with the keel 22 and feet, into conforming contact at the shoulder regions 171 of the cut-out edges. In this condition the anchorage withstands both outward pull and longitudinal pull with high strength, the shoulders 23 contributing to the longitudinal strength in combination with the dropped plunger 24. All of this is known, and it will be understood that various other kinds of anchorage device, as well as articles such as seats etc. incorporating such anchorage formations, are well known and may be used.

[0046] FIG. 4 shows the prior art device under a lateral load, indicated by arrow “F”, causing it to tilt around a longitudinal axis relative to the track 1. FIG. 4 indicates a track plane “TP” parallel to the track's outward face 16 and orthogonal to a median plane (not indicated) extending along the track. A base whose vertical level is not significant—can be used as an angular reference for the tilted and inclined parts and regions of the structure.

[0047] In the tilted position shown, representing a moderate load under which there is no significant deformation of the structure, the device 2 tilts bringing the outward surfaces 211 of its feet into contact against the inward surface 141 of the retaining flange 14 on a first side (the right-hand side shown) while on the second side the foot does not contact the track channel interior; rather the tilt is limited on that side by contact of the laterally-outward edge of the device body against the flat top outward surface 16 of the track. There is contact, or near-contact, between foot surface 211 and flange surface 141 over a contact region indicated as a region 215 of the flange and a region 145 (shown on the second side, for clarity) of the foot.

[0048] The track profile shown is a conventional one, designed for easy manufacture and combination of the device feet, combined with strength of the track against usual forces, especially longitudinal and outward forces. The contact region 215 of the flange inward surface 141 makes an angle to the track plane of about 15° in the tilted position shown. It is substantially, even if not exactly, contacted by the corresponding contact region 145 of the device foot 21.

[0049] Our testing has shown that when under lateral loads, this conventional track/foot form represents a weakness in that the action of the out-lifting first side of the foot 21 against the sloping underside of the flange 14 tends to push or peel the flange 14 out laterally out sideways as well as upwardly, this lateral action causing the flange to bend out without fully exerting its resistance to breaking at the root at the top of the side wall.

[0050] A first embodiment of our proposals is shown in FIGS. 5-8, which correspond in presentation to FIGS. 1-4 and the same reference numerals are used insofar as the same components and elements are present. Incidentally the device 2 is shown without its plunger 24, exposing the plunger mount 242 of the body; this is not significant. The plunger is present in the device as used.

[0051] In this system the inter-fitting parts of the device and track are differently formed. The device foot 21 more closely fills and complements the channel interior 10. The inward surfaces of the flanges 14 of a contact region 215 with a (laterally) outer sub-region 8 substantially parallel to the track plane and an inner sub-region 7 also substantially parallel to the track plane, with a step 9 between them so then the inner region 7 lies inwardly (in the vertical or inward/outward sense) of the outer sub-region. Thus, unlike the prior art contact region 215 of FIG. 4 which made about 15° positive angle with the track plane, the corresponding region in the present embodiment makes a slight negative angle with the track plane. This is because of the step. The individual sub-regions make a substantially 0 angle with the track plane. The result is a slight overhang effect, or re-entrant form of the flanges 14 at the interior.

[0052] Correspondingly, the outward surfaces 211 of the feet 21 have a form, where they underlie the flanges and therefore establish a contact region 145 with them, which again makes a slightly negative angle to the track plane in the angle convention used herein, having (laterally) inner and outer sub-regions 4,5 connected through a step 6 whereby the outer sub-region 4 is recessed outwardly (in the vertical sense) relative to the outer sub-region 5. These formations complement the flange formation so that firstly, when they meet under application of a lateral force “F” as shown in FIG. 8, the force between them acts substantially perpendicular to their abutting surfaces at both the inner and out sub-regions thereof, and moreover substantially perpendicular to the general direction of the projection of the flanges 14 so that a sliding or peeling action is minimised. We find that this increases the failure strength for lateral load.

[0053] A further feature here is limitation of the tilt movement. Firstly, the components are relatively formed and dimensioned so that when the tilt reaches contact as shown in FIG. 8, limited by the above-mentioned contact of the foot with the flange combined with, on the second side, contact of the body underside against the track outward surface, the tilt angle of the body relative to the track plane TP is less than in the conventional device. For example it may be less than 4°, perhaps about 2°, compared with the prior art device in which the angle at tilt contact is typically less than 6° but may be about 4°. This closer fit helps to square the contact between foot and flange in the corresponding direction of force application.

[0054] A further refinement is the provision of a depression 165 in the outward surface of the track towards the lateral edge of the region overlain by the undersurface of the device body. In this embodiment the depression is a generally part-circular-section groove extending longitudinally, and visible also in FIGS. 5 and 7. The body undersurface 27 carries a corresponding part-circular-section projection 271—one or more local nibs, or a longitudinally-extending rib—at each side, positioned so that when a side of the device tilts into contact with the track outer surface 16, the projection 271 enters the recess 165 and resists lateral movement, helping to reduce the stress on the parts of the track flange contacted from beneath by the foot 21.

[0055] It should be understood that while the feet may or may not be substantially circular in plan outline, the contact area formations described herein do not generally extend around circularly, but extend longitudinally with maintained cross-sectional shape at the contact region as seen in FIG. 6, so as to complement the corresponding contact regions of the track flange over an appreciable length.

[0056] FIG. 8 shows a further refinement in which the base surface has a central outward eminence 112 between a pair of lateral troughs 113, whereas the inward surface of the foot 21 has a central recess 216 to accommodate the base eminence 112, with downward ridges to either side which project into the troughs 113 of the base. These formations are not designed to contact one another, but to provide a “key” relation between the components so that a device with feet not adapted to conform to the special flanges of the track cannot normally be inserted into the track because its (typically flat) underside will foul the eminence of the track base before it can be full inserted.

[0057] FIGS. 9 to 12 show a second embodiment. This retains most general features of the first embodiment, but the contact regions of the track flange and device feet are differently formed, as is also the recess formation of the track outward face 16 that inhibits sideways sliding of the abutting device body 20 when tilted.

[0058] Specifically, in this embodiment the steps 6,9 of the foot contact region and track flange contact region are in the opposite lateral direction so that the (laterally) inner sub-regions 4,7 lie slightly outward (above) relative to the (laterally) outer sub-regions 5,8 of the components, although as before these regions in themselves are formed substantially parallel to the track plane. It is of course possible, in either embodiment, to adjust the surface angles in view of the expected slight tilt angle, to get more exact contact over these surfaces in the tilted condition. While this opposite direction of the step has a result of creating some positive overall angle (towards the center) of the track flange inward surface, it makes the components easier to manufacture. Moreover the angle over the entire contact region is still less than in the prior art device, and is less than 10°, while the corresponding angles of the sub-regions 7,8 are substantially zero so that contact there generates little or no lateral component by cam action.

[0059] As regards the abutment against the track outer face, in this embodiment the undersurface 27 of the body 2 is flat and plain as in known devices, but the outward face 16 of the track features a slight ramp forming a depression, groove or inward angle 165 and a corresponding gentle shoulder incline 166 laterally outside it, increasing resistance to sideways movement of the body 20 in the tilted condition and thereby providing additional strength in the engagement between the anchorage device and the track.