GB2241516A

GB2241516A - Insulated panels and assemblies

Info

Publication number: GB2241516A
Application number: GB9003667A
Authority: GB
Inventors: John Statham
Original assignee: TEMPERATURE CONTROLLED TECHNOL; TRUCK PANELS Ltd
Current assignee: TEMPERATURE CONTROLLED TECHNOL; TRUCK PANELS Ltd
Priority date: 1990-02-17
Filing date: 1990-02-17
Publication date: 1991-09-04
Also published as: GB9003667D0

Abstract

The panels 10 of an insulated container e.g. for commercial vehicles comprise a pair of spaced apart outer skins 12 composed of plywood to the outer faces of which are bonded glass reinforced plastic layers 14. The skins 12 enclose an insulating core 16 of foamed plastics material, and at least top and bottom edges of the panels are provided additionally with load bearing and distributing strips 18 of aluminium alloy bonded by their outer faces to the inner faces of the plywood skins 12. The strips 18 are also bonded by their inner faces to insulating core material 20 having a density greater than that of the core 16 of the remainder of the panel. A door comprises aluminium skins bonded to a foam core. An adjustable bulkhead panel is disclosed fig 5 (not shown). Details of floor and roof joints are disclosed. <IMAGE>

Description

IMPROVEMENTS IN OR RELATING TO INSULATED PANELS The present invention concerns improvements in or relating to insulated panels, particularly but not exclusively panels for use in the construction of refrigerated containers and commercial vehicles.

According to the first aspect of the present invention there is provided an insulated panel comprising an insulating core member including a load bearing and moisture resistant skin bonded to its outer surface and an additional load bearing and distributing strip sandwiched between the core and the skin along at least one of the outer edges of the panE^l.

Preferably the load bearing and distributing strip is manufactured from aluminium alloy. It is preferable that the strip has a thickness of 2mm.

Preferably tie core comprises a foamed plastics material, for examplE! styrofoam or polyurethane.

Preferably the skin comprises an inner layer of plywood and an outervtear and moisture resistant layer.

The outer layer may comprise glass reinforced plastics material, aluminium alloy or steel.

Preferably the core alongside the load bearing and distributing strip(s) is denser than the core material of the remainder of the panel.

The load bearirg and distributing strip(s) may be provided on both or on only one face of the panel.

Preferably the inner plywood skin is of 4mm thickness and the outer skin of imm thickness.

According to a further aspect of the present invention there is provided an insulated door comprising a peripheral frame member and an insulated panel including an insulating core member with load bearing and moisture resisting metal alloy skins of at least 2.5mm thickness bonded to its outer surface and hinge members mounted to the panel by bolts engaged in internally threaded pop rivets fitted to the panel.

Preferably the frame member is of channel section.

It, and the alloy skins may be manufactured from aluminium alloy.

Preferably the channel member carries sealing strips.

Preferably the panel may be provided with load bearing and distribution strips at selected regions to accommodate further internally threaded pop rivets with which additional door operating components can be attached.

According to a further aspect of the present invention there is provided a front bulkhead for an insulated container comprising a pair of elongate corner members arranged on either side of an insulated centre panel, each corner member comprising an outer and inner glass reinforced plastics material skin members bonded to and spaced apart for each other by an insulating core, the outer and inner skin members defining a corner with one limb of the corner defining a channel adapted to receive an insulating panel, the other limb defining a wall the end of which is adapted to abut the entral insulated panel.

Preferably the outer glass reinforced plastic skin member is radiused and is of increasing thickness along said radius region, the greatest thickness being at that part of the skin defining the channel for the panel.

Preferably the wall section of the corner member is bonded to a hardwood timber member spanning the gap between the outer and inner glass reinforced plastic skin members.

Preferably the outer and inner glass reinforced plastic skin members extend inwardly of the corner member over the end face of the timber member.

Preferably the insulating core of the corner member is high density polyvinyl chloride foam.

The centre elongate corner members of the bulkhead may be of variable width so that different width bulkheads and different types of refrigeration plant may be accommodated by altering the width of said members.

Preferably the centre member of the bulkhead incorporates within its foam core a load bearing member on which, for example, refrigerating plant may be supported, According to a further aspect of the present invention there is provided an insulated floor member for use in the contruct i on of an insulated container, the floor member having fixed round its periphery an upwardly projecting member of a relatively rigid material adapted to receive fastening by which additional components may be fixed to it.

Preferably said upwardly projecting member is manufactured from polypropylene and is fixed to an upper member of the floor assembly by suitable fixing means.

Preferably the floor comprises an insulated core to the upper outer face of which is bonded one or more plywood layers faced by a skin of moisture and wear resistant material. Said wear and moisture resistant skin may be of glass reinforced plastic material or alloy Preferably said outer skin extends upwardly over the innermost face of the upwardly projecting member.

The outer periphery of said floor member is preferably surrounded by a mild steel angle section.

Preferably said angle section extends over the outer face of said upwardly projecting member.

Embodiments of the present invention, in its various aspects will be described by way of example only with reference to the accompanying drawings in which : Fig.1 shows an exploded perspective view of the joint between a floor and a side wall of an insulated container, Fig.2 shows a cross-sectional view of the joint between the side wall and roof of an insulated container, Fig.3 shows a cross-sectional or fragmentary perspective view of a door and side wall of an insulated container, Fig.4 shows a cross-sectional view of an edge portion of the side wall of Fig.3, Fig.5 shows an exploded perspective fragmentary view of a front bulkhead and side walls of an insulated container, Fig.6 shows a cross-sectional fragmentary plan through a corner of the front bulkhead, and Figures 7 and 8 show cross-sections of the joint between the side wall and floor of two embodiments of the invention.

The construction of insulated containers, especially insulated containers for use on commercial road vehicles, has, in general terms, been accomplished up to the present time by designing and building containers unique to each vehicle type.

The efficient construction of the insulated panels from which the containers are made up is a skilful operation often involving the use of relatively expensive plant, the maximum capacity of which is not utilised as the individual container constructor does not manufacture sufficient containers. As a result an increase in efficiency can be obtained by a centralising panel manufacture and standardizing panel design.

One of the overall objects of the various aspects of the present invention is to achieve this aim.

Clearly the stucture of the insulated panels utilised in the container must be sufficient to withstand the loads to which they are subjected, provide sufficient insulation, give sufficient durability etc., but they also must be as lightweight as possible to reduce the self weight of the container without detracting from their structural stability and the ability of the individual manufacturer to fix panel to panel and assemblies of panels to floors, roofs etc. An object of one particular aspect of the present invention is to provide a panel which compares favourably with existing panels, is universally applicable, but is of lighter weight without sacrificing its structural properties.

The accompanying drawings show an insulated panel according to the present invention, in Fig.1 in combination with the floor of an insulated container, and in Fig.2 in combination with the roof.

The panel 10 comprises a pair of spaced apart first outer skin members 12 of four millimetre thick waterproof plywood. Bonded to the outer faces of said plywood skins are glass reinforced plastic layers 14 providing the panel with wear and moisture resistance and additional strength.

Between the plywood skins 12 there is provided a core 16 of foamed plastics material, for example styrofoam or polyurethane foam. Up to this stage the construction of the panel 10 is eFfectively standard and it is manufactured by coating the various components with adhesive and consolidating them in a vacuum press or forming the foam in the cavity defined between the two plywood skins 12 and supporting members of the manufacturing apparatus, the foam expanding during manufacture and bonding itself to the inner faces of the plywood.According to the present invention the panel 10 is provided additionally along at least its top and bottom edges with load bearing and distributing strips 18 in the form of 2mm thick aluminium alloy, the strips being bonded to the inner facing faces of the plywood members 12 by their outer faces and by their inner faces to a foam plastics material insulating core 20 having a density greater than the density of the core 16 of the remaining panel. It will be realised that the assembly of the core 20 and strips 18 may be pre-manufactured and positioned between the plywood sheets 12 (being bonded thereto) prior to the formation of the main insulating core 16 of the panel.

Fig.1 illustrates the use of the load bearing and distributing strips 18 in the joint between the floor 20 of the insulated container and a side panel 10. On assembly the lower edge of a panel 10 can be rested on an upwardly projecting member 22 (to be described below) and fixed to the floor by external and internal glass reinforced plastics strips 24, 26 fastened to the floor and panel by any suitable fastener means for example pop rivets of 6mm diameter, and self tapping screws, the fasteners penetrating through the skins and load bearing and distributing strips 18, which strips readily distribute the "fastening loads" over wide areas of the panel thereby increasing the efficiency of the fixing.

Fig.2 shows the construction of the joint between the upper edge of the panel and the roof 28 of the container. Construction of the panel at the roof joint is similar to that illustrated in Fig.1 at the floor joint except that the outer skin and load bearing and distributing strip extends beyond the panel edge for a distance approximately equal to the thickness of the roof panel so that the roof panel may overlie the top edge of the side panel. 7he roof panel may be of similar construction to the side panel and may include load bearing members (not shown) incorporated therein. The roof panel typically is also provided with a load bearing and distributing strip 18 but normally though not exclusively on its upper outermost face.

The roof panel is fixed to the side panel by a glass reinforced plastic or metallic angle section 30 through which suitable fasteners can be inserted on the centre lines 32, these centre lines being located within channels in the strip 30 so that the heads of the fasteners can, after fitment, be covered by capping strip 34.

In certain instances those edges of the side panels which are vertical in use may incorporate load bearing and distributing strips 18 but these may be omitted in certain instances.

The rear wall of an insulated container for a commercial road vehicle normally comprises a double door hinged along its outer edges to the rear edge of the side panel assembly.

In the past doors for containers have comprised a heavy steel or wooden frame reinforced with additional steel or timber members to which hinges, catches and other door operating gear can be mounted. This results in a very heavy contruct.ion.

Utilising a panel 10' similar to that described with reference to Figures 1 and 2 a more lightweight but equally robust door can be provided according to the present invention; the side panel 10 to which the door 10' is hinged is of generally similar contruction to the side panel described with reference to Figures 1 and 2 and will not be described in any further detail at this stage.

It is mounted within a stainless steel vertical end frame member 40 manufactured in a channel section of 3mm thickness material. The channel section faces inwardly and has an inner limb 42 the height of which is greater than the outer limb 44. The panel 10 is fitted into the frame member 40 from the outer side of the container such that its inner face, around its periphery, abuts the inner face of the limb 42 and its outer face is flush with the outer face of the shorter limb 44. A glass reinforced plastic fixing strip 24 can then be attached to the frame member and panel to complete the assembly by utilising suitable fixing means arranged on the centre lines 32.

Prefereably the fixing means comprise blind fasteners of the pop rivet type. The strip 24 projects beyond the rear frame member of the container and has polyropylene pivot blocks 46 fixed thereto thereby providing a hinge member.

The door pane]. 10' comprises an insulated core 1 6 sandwiched between 3mm thick aluminium alloy outer skins 41 with the panel being constructed in a manner similar to the side panels 10. The door panel 10' is surrounded in an extruded plastics channel section frame 43, the width of the inwardly facing channel being just sufficient to accommodate the periphery of the panel therein. The channel member 43 has outer channels 45 fixed thereto to accommodate sealing strips 48.

The use of a 3mm aluminium alloy outer skin for the panel 10', that is an outer skin which is much more robust than that normally employed, enable hinges, latches and other door operating gear to be attached directly to the door panel rather than to steel or wooden members incorporated within t he door panel as has been the practice in the past. This results in a door of substantially lighter overall construction than those previously employed. The attachment of the hinges, latches and other gear is by means of RIVNUTS (Trade Mark) which are internally threaded pop rivets attached to the panel in the normal manner and adapted to receive fixing bolts therein, the bolts mounting the hinges, latches and other gear to the door.

Other region of the panel 10' providing the door may incorporate additional load bearing and distribution strips 18 and at these regions door operating gear, door latches etc., may be mounted by pop rivets.

Insulated containers are often provided with their own self contained refrigerating plant which is mounted to the front bulkhead of the container externally of the container.

The weight of the refrigerating plant can be considerable and consequently the front bulkhead requires additional reinforcement to carry such load.

Bearing in mind that an object of the present invention is to provide "the standard" panels manufactured at a central source rather than individually tailor made for each vehicle it can already be appreciated that varying vehicle lengths can readily be accommodated by varying side panel widths. In view of the fact that the front bulkhead has to be reinforced it has proved difficult in the past to provide a standard designer front bulkhead which is suitable for varying vehicle widths.

The aspect of the invention illustrated in Figures 5 and 6 illustrate a variable width front bulkhead capable of readily supporting refrigerating plants on varying width vehicles.

Fig.5 shows a front bulkhead assembly fixed to side panels 10 of the type described in Figures 1 and 2. The front bulkhead assembly comprises two proposed corner members 50 and an intermediate panel 52.

Fig.6 shows a cross sectional view of one corner member 50 and its associated side panel 10. The corner member comprises an outer and inner skin 52,54 of glass reinforced plastic both the outer and inner skins defining right angles with the outer skin 52 being radiused the thickness of the material of the radius increasing from the front of the corner to a maximum at its side. The spacing between the rearwardly directed limbs of the skins 52, 54 of the corner member is such that a side panel ay be neatly accommodated therein and fixed to the corner member suitable fastening means on the centre lines 32.

At their inner ends, the outer and inner skins 52,54 extend inwardly cover a major portion of the inwardly facing face of a hardwood timber edge member 56. A high density polyvinyl chloride foam core 58 fills the void defined by the inner face of the timber member 56 the inner faces of the outer and inner skin and the end of the side panel 10, the foam being bonded to the timber and the skins of the corner member. The increased thickness of the outer skin over the radius portion gives it impact resistance on those areas most likely to be subjected to impact damage in use.

The central panel of the front bulkheads can have its width varied in accordance with the width of the refrigeration plant and vehicle to which the container has to be fitted. It may be of any suitable constructions incorporating reinforcing means on which refrigerating plant can be supported.

When it has been manufactured to the appropriate width it is fitted between the corner members 50 by means of glass reinforced plastic fixing strip 24 arranged internally and externally on the container and fixed by suitable fixings to the timber members 56.

In the construction of insulated containers especially insulated containers for carrying food products one of the most difficult areas of manufacture is the joint between the floor and side panel as not only is this area subject to considerable loads both operational and impact but also it is difficult to seal efficiently against moisture in a manner which can be readily cleaned.

Figures 7 and 8 show two embodiments of a further aspect of the present invention.

Once again they show side panels 10 of the type described with reference to Figures 1 and 2 which will not now be described in further detail.

The floor assembly 60 is constructed in accordance with known practices. For example it may comprise upper load bearing surface of two layers 62 of 12mm thick waterproof plywood 2 layers 64 of 4mm waterproof plywood forming the base, a foamed plastic material insulating core 66 and a peripheral 3mm mild steel angle frame 68.

According to the present invention the floor assembly comprises also an upwardly projecting polypropylene strip member 70 screwed to the floor along the centre lines 72 and having its outer face contained within the upwardly projecting limb of the angle frame 68.

A non slip glass reinforced plastic floor surface 74 is shown in Fig.7 and it will be appreciated that this covering extends over the inner face of the member 70 thereby giving a waterproof and readily cleanable junction between the floor and upstanding wall on the innterior of the container. The side panel 10 is rested on the upper surface of the strip 70 and assembly of the side to floor is achieved by means of the glass reinforced plastic strips 24, 26 as described with reference to Figures 1 and 2.

In the modifications shown in Fig.8 the upper skin 76 of the floor assembly is a 5mm aluminium alloy plate.

In this modification the inner fixing strip 26 is arranged alongside the inner face of the upstanding members 70 and a 3mm alloy angle corner member 78 is fitted at the internal lower corner of the cotnainer.

Various modification can be made without departing from the scope of the present invention in all its aspects. For example, the various plastics and metal channels employed could take any suitable form and be manufactured from any suitable material so as to reduce the thermal conductivity across the panel without prejudicing its strength or weight. Certain panels could have a glass reinforced plastics material inner skin, especially the door panels, and the outer plan of the door panels could be any skin capable of receiving RIVNUTS.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. An insulated panel comprising an insulating core member including a load bearing and moisture resistant skin bonded to its outer surface and an additional load bearing and distributing strip sandwiched between the core and the skin along at least one of the outer edges of the panel.

2. An insulated panel as claimed in Claim 1 wherein the load bearing and distributing strip is manufactured from aluminium alloy and/or the core comprises a foamed plastics material, for example styrofoam or polyurethane.

3. An insulated panel as claimed in Claim 1 or 2 wherein the skin comprises an inner layer of plywood and an outerwear and moisture resistant layer, for example, glass reinforced plastics material, aluminium alloy or steel.

4. An insulated panel as claimed in any of the preceding claims wherein the core alongside the load bearing and distributing strip(s) is denser than the core material of the remainder of the panel.

5. An insulated door comprising a peripheral frame member and an insulated panel including an insulating core member with load bearing and moisture resisting metal alloy skins of at least 2.5mm thickness bonded to its outer surface and hinge members mounted to the panel by bolts engaged in internally threaded pop rivets fitted to the panel.

6. An insulated door as claimed in Claim 5 wherein the frame member is of channel section together with and, the alloy skins, is manufactured from aluminium alloy.

7. An insulated door as claimed in Claims 5 or 6 wherein the channel member carries sealing strips.

8. An insulated door as claimed in any of Claims 5, 6 or 7 wherein the panel is provided with load bearing and distribution strips at selected regions to accommodate further internally threaded pop rivets with which additional door operating components can be attached.

9. A front bulkhead for an insulated container comprising a pair of elongate corner members arranged on either side of an insulated centre panel, each corner member comprising outer and inner glass reinforced plastics material skin members bonded to and spaced apart from each other by an insulating core, the outer and inner skin members defining a corner with one limb of the corner defining a channel adapted to receive an insulating panel, the other limb defining a wall the end of which is adapted to abut the central insulated panel.

10. A front bulkhead as claimed in Claim 9 wherein the outer glass reinforced plastic skin member is radiused and is of increasing thickness along said radius region, the greatest thickness being at that part of the skin defining the channel for the panel.

11. A front bulkhead as claimed in Claims 9 or 10 wherein the wall section of the corner member is bonded to a hardwood timber member spanning the gap between the outer and inner glass reinforced plastic skin members.

12. A front bulkhead as claimed in any of Claims 9, 10 or 11, wherein the outer and inner glass reinforced plastic skin members extend inwardly of the corner member over the end face of the timber member.

13. A front bulkhead as claimed in in any of Claims 9 to 12 wherein the insulating core of the corner member is high density polyvinyl chloride foam.

14. A front bulkhead as claimed in any of Claims 9 to 13 wherein the centre elongate corner members of the bulkhead are of variable width so that different width bulkheads and different types of refrigeration plant may be accommodated by altering the width of said members.

15. A front bulkhead as claimed in any of Claims 9 to 14 wherein the centre member of the bulkhead incorporates within its foam core a load bearing member on which, for example, refrigerating plant may be supported.

16. An insulated floor member for use in the construction of an insulated container, the floor member having fixed round its periphery an upwardly projecting member of a relatively rigid material adapted to receive fastenings by which additional components may be fixed to it.

17. An insulated floor member as claimed in Claim 16 wherein said upwardly projecting member is manufactured from polypropylene and is fixed to an upper member of the floor assembly by suitable fixing means.

18. An insulated floor member as claimed in Claims 16 or 17 wherein the floor comprises an insulated core to the upper outer face of which is bonded one or more plywood layers faced by a skin of moisture and wear resistant material.

19. An insulated floor member as claimed in any of the Claims 16 to 18 wherein said wear and moisture resistant skin is of glass reinforced plastic material or alloy.

20. An insulated floor member as claimed in any of Claims 16 to 19 wherein said outer skin extends upwardly over the innermost face of the upwardly projecting member.

21. An insulated floor member as claimed in any of Claims 16 to 20 wherein the outer periphery of said floor member is surrounded by a mild steel angle section which extends over the outer face of said upwardly projecting member.

22. An insulated panel substantially as herein described and illustrated with reference to the accompanying drawings.

23. An insulated container of which at least the side walls are constructed from insulated panels as claimed in any of Claims 1, 2, 3, 4 or 22.

24. An insulated container as claimed in Claim 23 which also includes an insulated door as claimed in any of Claims 5 to 8.

25. An insulated container as claimed in Claim 23 or 24 which also includes a front bulkhead as claimed in any of Claims 9 to 15.

26. An insulated container as claimed in any of claims 23 to 25 which also includes an insulated floor member as claimed in any of Claims 16 to 21.