GB2139557A

GB2139557A - Improved flooring panel and vehicle floor

Info

Publication number: GB2139557A
Application number: GB08406771A
Authority: GB
Inventors: William Alfred Lallyet
Original assignee: MALLINSON DENNY
Current assignee: MALLINSON DENNY
Priority date: 1983-05-10
Filing date: 1984-03-15
Publication date: 1984-11-14
Also published as: GB8406771D0

Abstract

A flooring panel for a load-carrying vehicle comprises an upper aluminium sheet (10) having a tread pattern (12), a lower sheet (16) of high-tensile aluminium, and an intermediate plywood laminate sandwich (14). In a vehicle floor, the grain of the outer layer or layers of the laminate sandwich may extend across the width of the vehicle spanned by the panel, and the transversely extending edges of adjacent panels are jointed over transverse bearers. <IMAGE>

Description

SPECIFICATION Improved Flooring Panel and Vehicle Floor Field of Invention This invention concerns a flooring panel suitable for forming the floor of a load-carryiny vehicle such as a brewer's dray or trailer, and also concerns a vehicle floor utilising said panels.

Background to the Invention In all load-carrying vehicles unloaded weight is often of primary consideration since this will to a large extent dictate the load-carrying capability of the vehicle all other factors being equal. Whilst the sides of such vehicles can be made relatively thin and when the load is well secured, even omitted or formed largely from fabric or the like, the floors of such vehicles must necessarily be strong enough to withstand the loads to be carried, and in particular, in many cases must be capable of withstanding concentrated loads and impact loads during loading and unloading due to accidental dropping of load members thereon.

This is particularly the case where brewer's drays are concerned since the frequent dropping of a keg or barrel is a regular occurrence during loading and unloading.

It is an object of the present invention to provide an improved flooring panel for loadcarrying vehicles, particularly brewers' drays and other load-carrying vehicles in which there is a possibility of concentrated loads and impact loads.

It is known to fabricate a panel from a rigid, thick metal sheet and secure thereto a sheet of plywood and to mount the panel within a supporting structure with attention taken to the direction in which the 'grain' of the plywood sheet runs so as to obtain desired loading capabilities.

Such known panels are heavy and relatively thick and must be laid with careful attention to the grain direction to be able to withstand concentrated loads.

Summary of the Invention According to one aspect of the present invention a flooring panel comprises 1) an upper sheet of metal, forming the loading surface; 2) a lower thinner sheet of high-tensile metal, forming the underside of the panel, and 3) a sheet of laminated material sandwiched between the said upper and lower metal sheets and bonded thereto over the adjoining surfaces.

Preferably the upper metal surface is formed with an upstanding tread pattern to improve grip when walking thereon and to permit air or fluids to flow below load members carried thereon.

In one embodiment the laminated sheet may be formed from layers of plywood with the grains of alternate layers running at right angles.

In another embodiment the laminated sheet may be formed from a plurality of outer plywood layers with parallel grains on each side of one or more inner layers the grains of which run at right angles to the outer layers. A plurality of such inner layers may themselves form a sandwich with one or more further inner layers the grains of which run parallel to the outer layers.

In one example of the first embodiment of the invention, the upper sheet is of aluminium and is typically 2 mm thick except in the region of the tread pattern where its thickness is typically 4 mm; the sandwiched laminated material is plywood with the grains of alternate layers running at right angles, having an overall thickness of 1 7 mm or thereabouts; and, the lower sheet is of 18 gauge (1.2 mm thickness) high-tensile aluminium.

In a first example of the second embodiment, having a total overall thickness of approximately 20 mm, the laminated sheet would again have a thickness of about 1 7 mm, and the metal sheets would have a thickness of approximately 2 mm and 1 mm respectively. In this example the laminated sheet may for example have three outer layers on each side of a single inner layer whose grain runs at right angles to that of the outer layers.

In a second example of the second embodiment having an overall thickness of approximately 30 mm the laminated sheet would have a thickness of approximately 27 mm and the aluminium sheets thicknesses of 2 mm and 1 mm approximately, and the laminated sheet may for example have three outer layers on each side of an inner sandwich the six layers consisting of two adjacent innermost layers whose grains run normally to the parallel grains of the outer layers, a next innermost layer on each side with its grain parallel to that of the outer layers, and an outer layer on each side of the inner sandwich with grain running at right angles to the parallel grains of the outer layers.

It has been found that a floor panel constructed in accordance with the invention can withstand, the impact of an 11 gallon beer barrel dropped from a height of a metre above the floor, even when the barrel is full of beer.

A surprising advantage of the invention is that it does not appear to be important as far as impact strength is concerned, as to which direction the grain of the plywood runs. This results in the panel being capable of being cut and fitted at will.

It is also surprising to find that the upper sheet of aluminium having only a basic thickness of 2 mm is nevertheless capable of withstanding a concentrated load equivalent to the dropping of a full 11 gallon beer barrel thereon from a height of a metre (when the sheet forms the upper layer of the sandwich construction forming the invention).

In the case of the first embodiment of the invention bending resistance is generaily the same in any direction. This allows such panels to be cut and fitted at will without regard to grain direction of the laminated sheet.

However in the case of examples of the second embodiment maximum resistance to bending under a sustained applied load, will normally only be obtained if the grain of the outer plywood layers of the laminated sheet runs parallel to the shorter span between supporting members.

It is also surprising that the upper and lower metal sheet members do not need to be bonded to each other at their extreme ends or side edges, or both, to form a box-like structure which is more typical of a load-bearing structure, although such edges are preferably either capped or fitted under the top flange of the mainside frame.

The invention also lies in a load-carrying vehicle floor when fitted with one or more flooring panels which embody the invention.

Thus, according to another aspect of the invention, a vehicle floor comprises at least one panel member as hereinbefore defined spanning the width of the vehicle and supported at its opposed ends by the mainside frame of the vehicle and on intermediate positions by chassis members running the length of the vehicle.

Usually the vehicle will comprise a plurality of floor panels, jointed at adjacent edges across the width of the vehicle.

One possible joint construction is disclosed in our copending Application No. 8318343, according to which the panel edges (in the direction of the width of the vehicle) have tapered edges which half-lap with corresponding edges of adjacent panel members, in particular over transverse bearers which extend across the width of the vehicle.

Bolts or rivets or the iike are entered through the overlapping regions of adjoining panels, and also pass through a top flange of the transverse bearer. The tapered edge regions of panels are formed by extended aluminium edge elements.

In accordance with the present invention, the edge elements are contained within the outer metal sheets of adjoining panels, the upper sheet of one panel and the lower sheet of the other being apertured to receive the fixing bolt or rivet.

Thus, a substantially continuous floor surface is achieved, and also a substantially continuous sheet of high-tensile metal on the underside. It is found that such a structure is highly resistant to damage, even if a heavy load is dropped on to the floor at or adjacent the joint. Additionally, the bending stiffness of the bearer is enhanced by the inherent stiffness of the panel edge extrusions.

A preferred transverse joint bearer for the vehicle floor is a light steel I-beam or an aluminium alloy channel section. The latter mentioned I-section or channel section can also be employed as a transverse bearer at positions other than the transverse joints. At the joints, it is preferred for the bolt or rivet to penetrate the top flange of the bearer at a point spaced appreciably within the free edge or edges of said flange.

Furthermore, it is desirable that a predetermined minimum distance (say 1 5 mm) is maintained between the centre of the join (midpoint of the bearer) and the edge of each panel. In practice a minimum overall flange width of at least 50 mm is employed.

A preferred alternative bearer for the transverse joints between panels is a beam with a central upstanding rib on its top flange, against which the straight-cut edge of two adjoining panels can abut on opposite sides (of said rib).

The rib serves to prevent indentation of the panel edges due to an impact at or adjacent the joint, and the top surface of the metal tread sheet of the floor panels can be fillet welded to the upper end of the rib to produce a substantially sealed floor of integrated construction. A minimum flange width of 34 mm on each side of the central upstanding rib is preferred, i.e., a minimum overall flange and ribs width of 76 mm (where the rib is some 8 mm thick).

Where bolt or rivet fixings are employed at transverse bearers (at a joint or intermediate joints) the fixing bolts or rivets may be laterally staggered from one to the next in the direction of the length of the vehicle.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a cross-section through a floor panel embodying the invention; Figures 2 to 4 are similar cross-sections through differing embodiments of the floor panel; Figure 5 shows part of a vehicle floor in accordance with the invention, wherein two floor panels are jointed above a transverse bearer; Figures 6 to 8 show differing arrangements of jointing and support the floor panels on bearers; Figure 9 shows a still further jointing arrangement at a transverse bearer; Figures 10 to 12 show differing mountings for the floor panels at the vehicle mainside frame; and incorporating the floor panels.

In Figure 1, 10 designates an upper sheet of aluminium having a tread pattern formed therein by means of integral upstanding regions 12. The sheet 10 is bonded to the upper surface of a plywood laminated sheet 14 and a thin plate 16 of high-tensile aluminium is bonded to the underside of the plywood laminate.

In order to withstand a shock load provided by a full 11 gallon beer barrel dropped from a height of over a metre, the upper sheet is some 2 mm thick with upstands of the same thickness whiist the lower panel is of 18 gauge high-tensile aluminium and the intermediate sheet 14 is of laminated plywood layers having some 17 mm overall thickness.

Differing embodiments of floor panel are shown in more detail in Figures 2 to 4.

In Figure 2, the plywood intermediate sheet 14 has seven plywood layers whose grains extend at right angles alternately from one layer to the next.

In Figure 3, seven plywood layers are also employed, but only the innermost central layer has a cross-grain.

Figure 4 shows a floor panel of some 30 mm total thickness; the top and bottom aluminium sheets are similar but the plywood sandwich 14 has twelve layers, including four selectively positioned inner layers, as illustrated, with a cross-grain.

In constructing a trailer floor in which the main supports for the panels run from front to back of the vehicle, the floor panels are to span the vehicle from side to side, sandwich 14 extending transversely to the length of the vehicle. This orientation is especially with the embodiments of Figures 3 and 4, to provide good resistance to bending under load.

As shown in Figures 10 to 12, the vehicle floor panels 20 may be supported between the mainside frames 22, with intermediate support by the main longitudinal chassis members 24, as indicated in Figure 13A. The panels are jointed, transversely of the vehicle to form an integrated floor. These joints are produced by fitting the adjacent edges of two panels together above transverse bearers.

Figure 5 shows one jointing arrangement, conveniently for adjacent panels 20A, 20B with half-lapped tapered aluminium edge extrusions, as described in our corresponding Application No.

8318343.

An aluminium alloy channel section bearer 26 is utilised, having a top flange 28 to which the overlapping edge regions of the panels are fixed by bolts 30 (riveting is an alternative possibility).

It is to be noted that the edge extrusions 32A, 32B are accommodated within the outer aluminium sheets of the panels, these sheets being suitably apertured to receive the fixing. The near continuity of the upper and lower aluminium sheets provides improved resistance to floor damage if a load is dropped onto the floor adjacent the joint. Fixings may be provided every 300 mm or thereabouts.

Figures 6 to 8 show other differing embodiments of joint above a transverse bearer.

In Figure 6, a light steel I-beam 34 is employed as the transverse bearer, together with a fixing in the form of a self-tapping screw or rivet 36. The rivet head is not countersunk, as is to be preferred for vehicle floors to be subject to very heavy loadings. Figure 8 shows an aluminium channel section bearer 38 to which the overlapping panel ends are screwed or riveted at 40, whilst Figure 7 shows an intermediate bearer 42 to which the floor panel 20 may be screwed or riveted at a point 43 between transverse joints.

Figures 6 and 8 also show that the fixings of the joints, typically every 75 mm across the width of the vehicle, may be staggered in the direction of the length of vehicle, e.g. from towards one side of the top flange of the bearer to a position towards the other side. The line referenced 44 indicates the edge of a tapered edge region of the panel 20, and it is preferred for the distance of this edge from the centre of the joint (indicated by line 46) to be not less than 1 5 mm. Additionally, it is preferred for the rivet (or self-tapping screw or bolt) fixing 36 or 40 to be spaced appreciably inwards of the edge of the bearer flange. In practice, therefore, a flange width of at least 50 mm is preferred.

In the case of intermediate bearers 42 between the transverse joints (Figure 7), non-staggered fixings, typically 300 mm apart, may be employed. The panel 20 is apertured at the appropriate points to take these fixings.

Figure 9 shows another transverse jointing arrangement utilising floor panels 20A, 20B having straight cut edges. The bearer 46 has an upstanding rib 48 on its top flange, against which the panels about on opposite sides. The aluminium top sheet of the panels is preferably fillet welded to the top of the rib (as Figure weld 50 is illustrated) in order to form an integrated, sealed floor structure. Fixings may be spaced at 150 mm.

Figures 13 and 1 3A show that, especially in the case of a trailer or other vehicle of lower load capacity, it is possible to construct the complete floor without employing transverse bearers, provided the grain of the outer layers of the plywood sandwich runs transverse to the length of the vehicle. However, it is an additional advantage of all embodiments of this invention that the floor is able to take very substantial loads, with high resistance to impacts, including impacts of or adjacent the joint between panels, with minimal support from underframe members. This is of particular advantage of vehicle designs where a small ground to floor height is desired.

Claims

1. A flooring panel comprising: (a) an upper sheet of metal, forming the loading surface; (b) a lower thinner sheet of high-tensile metal, forming the underside of the panel, and (c) a sheet of laminated material sandwiched between the said upper and lower metal sheets and bonded thereto over the adjoining surfaces.

2. A flooring panel according to Claim 1, wherein the upper sheet carries a tread pattern.

3. A flooring panel according to Claim 1 or Claim 2, wherein the laminate sandwich comprises layers of plywood.

4. A flooring panel according to Claim 3, wherein the layers of plywood alternately have grains at right angles.

5. A flooring panel according to Claim 3, wherein the plywood laminate sandwich has a plurality of outer layers on each side, all with parallel grains.

6. A flooring panel according to Claim 5, wherein the laminate sandwich has at least one inner layer with cross-grain relative to that of the outer layers.

7. A flooring panel according to Claim 6, wherein the panel has an edging adapted for interfitting with the edging of an adjacent panel along its opposed sides parallel to the grain of the outer layers of the laminate sandwich.

8. A flooring panel according to any one of Claims 1 to 7, wherein the upper end cover sheets are made of aluminium.

9. A flooring panel according to Claim 8, wherein the upper sheet has a thickness not including any tread pattern, in the range 1.5 to 3.0 mm.

10. A flooring panel according to Claim 9, wherein the lower sheet has a thickness in the range 0.50 to 1.75 mm.

11. A vehicle floor comprising one or more flooring panels as defined in any of Claims 1 to 10.

12. A vehicle floor according to Claim 10, having a plurality of panels each spanning the width of the vehicle and supported at opposed ends by the mainside frame of the vehicle.

13. A vehicle floor according to Claim 12, wherein the panels are also supported by the main longitudinal chassis members of the vehicle.

14. A vehicle floor according to claims 12 and 1 3, supported with the grain of the outer layer or layers of the plywood laminate sandwich running across the width of the vehicle.

1 5. A vehicle floor according to Claim 14, wherein the transversely extending longitudinal edges of adjacent panels are jointed together.

1 6. A vehicle floor according to Claim 15, wherein the joints are affected over transverse bearers.

17. A vehicle floor according to Claim 1 6, wherein the transverse bearer has a top flange to which half-lapped edge regions of adjacent panels are secured by fixings such as bolts or rivets.

18. A vehicle floor according to Claim 17, wherein the half-lapped edge regions of the panels are formed by edge extrusions.

1 9. A vehicle floor according to Claim 18, wherein the edge extrusions are accommodated within the upper and lower facing sheets of the respective panels, the fixing penetrating the upper sheet of one panel and the lower sheet of the other.

20. A vehicle floor according to Claim 19, wherein the fixing is spaced a predetermined minimum distance from the edge of the bearer top flange and the edge of each panel is spaced a predetermined minimum distance from the centre of the joint.

21. A vehicle floor according to Claim 1 6, wherein the top flange of the bearer has an upstanding rib against which the edges of adjacent panels abut on opposite sides.

22. A vehicle floor according to Claim 21 wherein the upper sheets of the panels are welded to the upstanding rib.

23. A flooring panel substantially as hereinbefore described with reference to Figures 1 to 4 of the accompanying drawings.

24. A vehicle floor substantially as hereinbefore described with reference to Figures 5 to 13 of the accompanying drawings.