AU2011253744A1

AU2011253744A1 - A Support Tray

Info

Publication number: AU2011253744A1
Application number: AU2011253744A
Authority: AU
Inventors: Jeremy Gray
Original assignee: Assembly Electronics Pty Ltd
Current assignee: Assembly Electronics Pty Ltd
Priority date: 2010-03-05
Filing date: 2011-11-29
Publication date: 2012-07-12
Also published as: NZ596759A; GB201120563D0; GB2486762A; AU2011253744A8

Abstract

A support tray assembly includes extrusion having a profile defining at least one channel 2.010 having first and second side walls 2.006, 2.008 and an open end defining a channel aperture 2.022, wherein a re-entrant hook formation 2.014 is formed on the first side wall proximate the channel aperture. The assembly also includes a tray member 5.032 including a planar, substantially rectangular body having first and second parallel flanges 5.034, 5.036, along opposite sides of the tray body, the material of the tray member being stiff and flexible. The flanges engage the re-entrant hook formations of the extrusions. The flanges are adapted for insertion in channels of the support tray extrusions. Figure 5 I I I f4 4.042 FIGURE 4 4.04403 ... 4.044 4.032 4.034 -4.040 5.002 5.003 5.036 5.034 p5.046 6.036 6.034 7.060 7.062 7.036 7.034

Description

A Support Tray Field of the invention [001] This invention relates to a support tray. [002] The invention is particularly suited for use with light weight loads, such as power and communication cables for appliances and computers. The tray can be attached under a desk to hold the various wires. Background of the invention [003] One aspect of the invention relies on the stiffness of certain flexible materials such as polycarbonates and the like. [004] Stiffness is the resistance of an elastic body to deformation by an applied force along a given degree of freedom (DOF) when a set of loading points and boundary conditions are prescribed on the elastic body. The stiffness, k, of a body is a measure of the resistance offered by an elastic body to deformation. For an elastic body with a single Degree of Freedom (for example, stretching or compression of a rod), the stiffness is defined as k = F/6 where: F is the force applied on the body; 6 is the displacement produced by the force along the same degree of freedom. [005] The invention requires a material which has sufficient stiffness to resist compressive failure over a working load range. The invention also utilizes the flexibility of such materials. Summary of the invention [006] The present invention provides a support tray extrusion having a profile defining at least one channel having first and second side walls and an open end defining a channel aperture, wherein a re-entrant hook formation is formed on the first side wall proximate the channel aperture. [007] The extrusion can include an attachment flange. [008] The attachment flange can be transverse to a wall of the channel. [009] The attachment flange can be parallel with a wall of the channel. [010] The second side wall can be tapered proximate the open end.

2 [011] The invention also provides a support tray member including a planar, quadrilateral body having first and second parallel flanges along opposite sides of the tray body, the material of the tray member being stiff and flexible. [012] The tray member can be rectangular. [013] The flange can have a width, thickness, and stiffness such that it resists compressive failure within a predefined load limit. [014] The material of the tray member can be plastically deformed to form the flanges. [015] The material of the tray member can be thermally formed to form the flanges. [016] The invention also provides support tray assembly including at least one extrusion, and a tray member, wherein the channel aperture width is greater than twice the thickness of the tray member material. [017] The width of the support tray flanges can be greater than the width of the extrusion channel. Brief description of the drawings [018] An embodiment or embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [019] Figure 1 is illustrative of an extrusion according to an embodiment of the invention. [020] Figure 2 is an end-on view of the extrusion of Figure 1. [021] Figure 3 is illustrative of a tray member according to an embodiment of the invention. [022] Figure 4 is an end-on view of the tray member of Figure 3. [023] Figure 5 illustrates an assembled cable tray according to an embodiment of the invention. [024] Figure 6 illustrates an alternative tray assembly. [025] Figure 7 illustrates a closed tray assembly according to an embodiment of the invention. [026] The numbering convention used in the drawings is that the digits in front of the full stop indicate the drawing number, and the digits after the full stop are the element 3 reference numbers. Where possible, the same element reference number is used in different drawings to indicate corresponding elements. [027] It is understood that, unless indicated otherwise, the drawings are intended to be illustrative rather than exact representations, and are not necessarily drawn to scale. The orientation of the drawings is chosen to illustrate the features of the objects shown, and does not necessarily represent the orientation of the objects in use. Detailed description of the embodiment or embodiments [028] Figure 1 illustrates an extrusion 1.002 adapted to be attached to a surface and to engage one side of a tray member as will be described below. The extrusion has a first side 1.004 forming an attachment flange and a second side 1.008 transverse to the first side 1.004. A wall 1.006 is parallel to the second side 1.008 and spaced therefrom to define a narrow channel 1.101 with one open end. [029] Figure 2 illustrates detail of the extrusion of Figure 1 shown in cross-section. The first side 2.004 is shown as horizontal in this view. The second side 2.008 projects downward from the first side 2.002. The wall 2.006 is substantially parallel with the second side 2.008 and spaced therefrom by distance 2.024 to define a channel 2.010. The lower end of the channel 2.024 is open at aperture 2.022. The lower end of the second side 2.008 has a re-entrant hook-like formation 2.014. The channel 2.010 has a depth indicated at 2.020. [030] A longitudinal groove 2.012 is provided to provide a start for self-tapping screws. [031] Optionally a lower portion of wall 2.006 can taper to a narrower lower end as illustrated by angle 0, at 2.018. [032] The extrusion 1.002 can be of any desired length. [033] Figure 3 illustrates a tray member 3.030. The tray member is formed of a relatively thin, stiff, flexible, rectangular sheet and has a central body 3.032 and parallel flanges 3.034, 3.036 formed along opposite side. The material of the channel is flexible and stiff. The flanges can be formed by plastic deformation, or heat forming. [034] Suitable materials for the tray member include polycarbonate or other polymeric materials. [035] Figure 4 is an end-on illustration of the tray member of Figure 3. The central body 4.032 has a width 4.040. The flanges 4.034, 4.036 have a width 4.042 which is greater than the width 2.024 of the channel 2.010. The free ends of the flanges 4.034, 4 4.036 are spaced from the body 4.032 by a distance 4.044 which can be greater than the width of the channel aperture 2.022 to ensure that, once the flange is inserted into the channel, the resilience of the tray member material will cause the free end of the flange to be engages in the re-entrant hook formation 2.014 as shown in Figure 5. [036] Figure 5 illustrates a tray assembly according to an embodiment of the invention. The assembly includes a pair of extrusions 5.002, 5.003 mounted parallel with their attachment flanges facing away from each other. The extrusions are spaced apart by a distance less than the width 4.040 of the tray member 5.032. The edges of the tray member 5.032 with the flanges 5.034, 5.036 are inserted into respective channels of the extrusions 5.002, 5.003. Because the extrusions are spaced apart by less than the width of the tray member, the tray member, being flexible, adopts a curved profile. The flanges 5.034, 5.036 are longer than the width of their respective extrusion channels, and the material of the tray member is stiff, the flanges will remain substantially straight because they are comparatively short. [037] The free ends of the flanges 5.034, 5.036 will be engaged in the re-entrant hook formations 2.014 of their respective extrusions. [038] The width of the flanges 5.034, 5.036 is such that the junction or apex 5.050 of the flange with the tray body 5.032 will be pressed against the inner side of the wall, while the free ends of the flanges seat or sit in the re-entrant hook formation. The resilience of the tray material in cooperation with the re-entrant hook formation, provides a snap-lock function to flanges in the channel. Because the width of the flanges 5.034, 5.025 is greater than the width of the channel, the flanges will be inclined to the normal to the wall by an angle p, at 5.046. Preferably, p is greater than 450. Preferably, the angle is of the order of about 60*. [039] The weight of the cables in the tray is applied to each apex 5.050 of the flange and the tray body intersections along the tangent of the tray body at the apex. The apex 5.050 is pressed against the side of the channel. The dimensions of the channel width, the channel aperture width and the width of the flanges 5.034, 5.036, the spacing between the extrusions and the width of the tray body, stiffness of the tray body material, as well as the weight of the cables, will influence the tangent angle of the tray body at the apex. The closer the tangent angle of the tray body is to the flange angle the better the load is applied to the flange. Factors which limit the minimum tangent angle include the width of the channel, the width of the flange, and the width of the channel aperture. When the angle between the flange and the tray tangent is less than 45*, a substantial proportion of the load applied to the flange will be a compressive load. The flange has a width, thickness, 5 and stiffness sufficient to resist compressive failure under the loads normally applied during normal use. [040] The width 2.024 of the channel 2.010 is smaller than the fold 3.034. The channel aperture is sufficiently wide to permit the double thickness of the tray and fold to be pushed therethrough. The thickness of the tray member material can be of the order of about 0.2mm. The width of the flanges 5.034, 5.036 can be of the order of about 7 to 10 mm. The included angle of the flange 4.034 and the tray member body 4.032 can be within a range of approximately 30* to 60*. [041] The tray member can be inserted into the attached extrusions from an end, or by pushing the apex 5.050 of the flange body junction through the channel aperture 2.022 so the flange snaps into place when it is clear of the top of the re-entrant hook formation 2.014. The depth 2.020 of the channel can be sufficient to permit the flange to clear the top of the re-entrant hook formation. [042] As shown in Figure 6, the tray member 6.032 can be inserted upside down in relation to the arrangement of Figure 5. While this arrangement will function, the applied load to the flanges 6.034, 6.036 from the weight of the cables in the tray will be less optimally applied to the flange. [043] Figure 7 illustrates a further embodiment of the invention, in which the tray member is folded to provide a substantially closed channel. In this embodiment, the extrusions have a different shape. The extrusion attachment flanges 7.060, 7.062 can be formed by an extension of the side of the channel. A single extrusion with horizontally opposed channels can be used, or two individual opposed extrusions can be used. A substantially closed channel is formed by the tray body and the extrusions. [044] In this specification, reference to a document, disclosure, or other publication or use is not an admission that the document, disclosure, publication or use forms part of the common general knowledge of the skilled worker in the field of this invention at the priority date of this specification, unless otherwise stated. {045] In this specification, terms indicating orientation or direction, such as "up", "down", "vertical", "horizontal", "left", "right" "upright", "transverse" etc. are not intended to be absolute terms unless the context requires or indicates otherwise. These terms will normally refer to orientations shown in the drawings. [046] Where ever it is used, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is 6 the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear. [047] It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative aspects of the invention. [048] While particular embodiments of this invention have been described, it will be evident to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments and examples are therefore to be considered in all respects as illustrative and not restrictive, and all modifications which would be obvious to those skilled in the art are therefore intended to be embraced therein.

Claims

1. A support tray extrusion having a profile defining at least one channel having first and second side walls and an open end defining a channel aperture, wherein a re entrant hook formation is formed on the first side wall proximate the channel aperture.

2. A support tray as claimed in claim I including an attachment flange.

3. A support tray as claimed in claim 2, wherein the attachment flange is transverse to a wall of the channel.

4. A support tray as claimed in claim 2, wherein the attachment flange is parallel with a wall of the channel.

5. A support tray extrusion as claimed in any one of the preceding claims, wherein the second side wall is tapered proximate the open end.

6. A support tray extrusion as claimed in any one of claims 1 to 5, wherein the width of the channel is less than the width of an engaging flange of a support tray.

7. A support tray extrusion as claimed in any one of claims 1 to 6, wherein the open end of the channel defines an aperture having a width of between 0.5mm and 4 mm.

8. A support tray extrusion as claimed in any one of claims 1 to 6, wherein depth of the channel is greater than the width of an engaging flange of a support tray.

9. A support tray extrusion as claimed in any one of the preceding claims, wherein the re-entrant hook formation has an " shape.

10. A support tray member including a planar, substantially rectangular body having first and second parallel flanges along opposite sides of the tray body, the material of the tray member being stiff and flexible.

11. A support tray member as claimed in claim 6, wherein the flange has a width, thickness, and stiffness such that it resists compressive failure within a predefined load limit.

12. A support tray member as claimed in claim 10 or claim 11, wherein the material of the tray member is plastically deformed to form the flanges.

13. A support tray member as claimed in claim 10 or claim 11, wherein the material of the tray member is thermally formed to form the flanges.

14. A support tray assembly including at least one extrusion as claimed in any one of claims 1 to 9, and a tray member as claimed in any one of claims 10 to 13, wherein the channel aperture width is greater than twice the thickness of the tray member material. 8

15. A support tray assembly as claimed in claim 14, wherein the width of the support tray flanges is greater than the width of the extrusion channel.

16. A support tray extrusion substantially as herein described with reference to the accompanying drawings.

17. A support tray member substantially as herein described with reference to the accompanying drawings.

18. A support tray assembly substantially as herein described with reference to the accompanying drawings.