AU7180700A - Improvements in and relating to the construction of nets - Google Patents

Description

o 0 00 00 0 0 0 0 0 1

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION STANDARD PATENT "Improvements in and Relating to the Construction of Nets" The following statement is a full description of this invention, including the best method of performing it known to me: IMPROVEMENTS IN AND RELATING TO THE CONSTRUCTION OF NETS Background and Summary of the Invention This invention concerns the use of shock cord, particularly the use of shock cord in relation to nets, especially nets used for retaining, supporting and storing items carried in motor cars.

Shock cord is well known as a product suitable for retaining items in storage. It is an •"elasticised cord, available in a range of diameters including those from 4mm to 10mm. In its most common construction shock cord has a core of continuous rubber strands, each about lmm diameter and laid parallel to each other in the axial direction of the cord. The strands are retained by a surrounding sheath commonly made of woven nylon material or the like. Shock cords commonly stretch until the limit of the sheath fabric is reached. In Australia and New Zealand such shock cords are often known as bungee cords.

20 It is known for small nets to be manufactured for use in motor vehicles where such nets S:"i have a square panel of netting mesh with a length of shock cord laced into the perimeter :meshes, and the ends of the cord are tied together. Such nets have been fastened into motor .i vehicles inside against the roof to provide storage space and have been used to hold down on the floor items in the back of station wagon type vehicles to prevent their dangerous movement around the vehicle in the event of a crash.

Such nets however are not very suitable for holding against a short vertical surface such as the upstanding wall of a car boot immediately behind the rear passenger seat, or against the corresponding seat back in a station wagon whether or not the rear seat is folded forward.

There is a need for an improved configuration of a net-based storage container which provides more convenient use in such short vertical rise situations, and more secure 3 holding of loose items, as well as being useful in the same manner as previously available nets.

To achieve this end, it has been found desirable to create fixed size loops in shock cord at various positions around the perimeter of a net. But existing methods of forming such loops and of joining the free ends of the shock cord have substantial disadvantages. Knots joining the ends can come loose or are easily altered by users of the net in such a manner that the continued use of the net for restraining goods in a vehicle becomes a safety hazard because the loops are no longer properly formed or retained.

Various clamping devices have been tried as means for joining lengths of shock cord.

Included among these have been the type of clips commonly known as rope splice clips.

Such a clip comprises a piece of sheet metal bent more or less into a dual tubular shape having a figure 8 cross-section. Two ends of a rope are inserted into respective portions of 15 the figure 8 and the clip is then generally flattened in some way or pressed together to clamp the rope within it. However when such clips are used with shock cords, two problems may arise.

First, many of the clips have inwardly protruding prongs to help retain a rope, but these S 20 prongs can easily cut through or otherwise damage the rubber strands in the shock cord and .:.ooi substantially reduce the load capable of being handled by such a join. Also, even when inwardly protruding prongs are not used, it is common to find that a shock cord so clamped S. will slide out of the clip relatively easily when the cord is tensioned. This is because in the course of tensioning, the diameter of the shock cord is substantially reduced, and that reduced diameter allows the shock cord to easily slip out of the clip.

We have now developed a fastening system for joining two lengths of shock cord which does not suffer from the problems of such pre-existing clips.

Accordingly, in one aspect the invention provides a method of joining two lengths of shock cord having a given diameter when relaxed, said method comprising 4 passing the two lengths through a tube, said tube having an internal diameter of approximately 2d, two ends and a mid portion therebetween, (ii) squeezing the ends of the tube to plastically deform the ends of the tube, and thus compress the cord at the ends of the tube, while leaving the cord in the mid portion at least substantially uncompressed.

Preferably the tube has a length in the range of 3d to 5d. Preferably the length of the tube squeezed is in the range of 0.8d to 1.5d at each of its ends. Preferably the length of the mid portion is in the range of O.8d to In another aspect the invention provides a method of constructing a net wherein shock cord is threaded through mesh apertures in the net around the perimeter of the net, the two ends of the cord are joined according to any one of claims 1 to 5 and, at comers of the net, permanent loops are created in the cord by means of forming a bight in the cord and at the 15 neck of the bight joining the portions of cord on each side of the bight according to any one Qof claims I to In a further aspect the invention provides a net comprising a rectangular panel of netting mesh material with a length of shock cord threaded through the peripheral mesh apertures S 20 around the perimeter of the panel, the cord having a permanent loop created therein at each a..

of the four comers of the panel and the centre of each of the two shorter sides of the panel.

o In a further aspect the invention provides a net comprising a rectangular panel of netting mesh material with a length of shock cord threaded through the peripheral mesh apertures around the perimeter of the panel, the cord having a permanent loop created therein at each of the four corners of the panel and the centre of the two shorter sides of the panel, wherein each loop is created in the cord by means of forming a bight in the cord and at the neck of the bight joining the portions of cord on each side of the bight.

In a further aspect the invention provides a hanging storage container fitted to a generally vertical interior surface of a motor vehicle, said container being configured from a net as described above, wherein said net is folded once so that the shock cord on said two shorter sides forms two vertical edges at each end of the container and the shock cord also forms two horizontal edges along the top of the container, the container having a single bottom edge formed by the fold in the mesh, and wherein the four top corners of the container are firmly attached to the vehicle by said loops at the four comers of the panel and the two bottom corners are firmly attached to the vehicle by the loops at the centres of the shorter sides.

Brief Description of the Drawings In order that the invention may be more fully understood there will now be described, by way of example only, preferred embodiments and other elements of the invention with reference to the accompanying drawings where: Figure 1 shows a perspective view of a net according to one embodiment of the invention, 15 Figure 2 is a perspective view of a loop of shock cord and an associated hook which are part of the net shown in Figure 1, Figure 3 is a perspective view showing the net of Figure 1 folded in a configuration for use against the back of the rear seat of a station wagon, and Figures 4 and 5 are cutaway views showing successive stages in the formation of a 20 ferrule clamped onto the shock cord as shown in Figure 2.

ego oi oo.o.i Detailed Description of the Invention Referring to Figures 1 and 2, a net 10 comprises a rectangular panel of netting mesh 12 having two long sides 14 and two shorter sides 16. The mesh used has a diamond configuration twenty-two meshes wide and with smooth woven edges. When stretched out fully the sides of each mesh are approximately 25mm apart.

If laid out on a horizontal surface without stretching the shock cord, the net measures long and 60cm wide, so the side lengths are in the ratio 4:3.

6 The preferred netting material is braided and knotless, however knotted and twisted or woven netting is also possible. The netting may be made from any suitable materials but polyester and nylon are preferred. The mesh is woven in the first instance so that its total width is the same as the width of the panel required. The process used to make the panel of mesh is to cut off an appropriate length of the mesh using a heated knife operation which sears the strands of the netting and thus stops fraying. This does however produce a harder edge on the short sides 16 and 17 of the panel. Such a hard edge is avoided on the long sides 14 and 15 because the mesh is woven in the first instance to the correct width.

In each corner of the net, a loop 20 of the shock cord is formed as shown in Figure 2 and onto this loop 20 is located a hook 24 made of tough resilient plastics material. Each loop 20 is held in engagement with a respective hook 24 by means of a saddle portion 28 of the hook making a loose snap fit onto its respective loop 20. The hooks 24 allow convenient 15 attachment of the net to fixtures on the inside of a vehicle. Any suitable hook may be used S and, while open hooks are shown for ease of illustration in Figures 1 and 2, hooks having a °covered entry gate are preferred for security of fastening.

°oo.

Midway along the short sides 16, side loops 26 are formed from a bight of the shock cord 20 in a similar manner to the corner loops 20. The mid-side loops 26 provide a means by o=oo• which the "corners" of a net folded once lengthwise may be held in place.

ooooo Figures 4 and 5 illustrate the process of joining the two ends of the shock cord together in a manner whereby the will not pull apart. The two end portions 41 and 42 of a length of shock cordare fed from opposite sides into, and just through an aluminium tube 46 having an internal diameter slightly larger than the sum of the cord diameters. In the present case a tube of 9mm internal diameter is used with 4mm diameter cord. The tube is then placed in a shaped die and subjected to a pressing operation. By this means the collars 49 are pressed into the tube 46 and compressed into the shock cord 18. The cord is thereby significantly compressed at the site of each collar and this causes a displacement of the cord material so that it bulges into the barrelled mid-section 52. Accordingly, when an attempt is made to pull the shock cord out of the clamped fastener, the bulged out shock cord material provides a substantial locking action to the shock cord being pulled out of the fastener. The fastening cylinder is preferably pressed evenly around its perimeter so that the fasteners have a pleasing symmetrical form. Approximately one third of the length of the tube at each end is utilised for formation of the reduced diameter collar, so leaving one third of the length of the cylinder to take the form of the barrelled mid-section 52.

The dies for the clamping operation can include indentations and identification marks which would change the finish of the fasteners and could be used to identify the particular product. The fastener may be manufactured from a choice of materials including aluminium, copper, brass and bronze, stainless steel, or any combination of these metals.

The process used to make the net is to thread the shock cord through the meshes around the perimeter of the net and join the two ends with a connector 54 (as described with reference 1 to Figures 4 and 5) at the centre ofone ofthe long sides 14. Sufficient length of shock cord 15 is allowed so that the comer loops 20 and side loops 26 may be created by taking a bight of the shock cord at that position and passing it through a stretch cord fastener clip as S- •described earlier. Each loop carries a co-operating hook 24 and the hook may be fastened to a bracket or locating tabs which may be permanently attached to the motor vehicle in appropriate positions.

ooo.

2 The corner loops 20 are formed by taking a bight in the shock cord and pushing it through an aluminium tube 46 connector by the required amount before pressing the connector tube as described.

*0 In the preferred embodiment described above a 4mm diameter shock cord is used. The length of the panel is approximately twenty to thirty meshes. As an alternative, a stretch mesh may be used. The particular netting used is classed as a PX 70-90 ply. The size of the apertures in such meshes is conventionally designated as the size between both knots when stretched tight on the diamond configurations.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood 8 that the invention includes all such variations and modifications which fall within its spirit and scope.

It will be also understood that where the word "comprise", and variations such as "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge in Australia.

*ooo *ooo *oo oo* e•

Claims (9)

1. A method ofjoining two lengths of shock cord having a given diameter when relaxed, said method comprising: passing the two lengths through a tube, said tube having an internal diameter of approximately 2d, two ends and a mid portion therebetween, (ii) squeezing the ends of the tube to plastically deform the ends of the tube, and thus compress the cord at the ends of the tube, while leaving the cord in the mid portion at least substantially uncompressed.

2. A method according to claim 1 wherein the tube has a length in the range of 3d to *o 15 3. A method according to claim 1 or 2 wherein the length of the tube squeezed is in the range of 0.8d to 1.5d at each of its ends.

4. A method according to any one of claims 1 to 3 wherein the length of the mid S portion is in the range of 0.8d to A method according to any one of claims 1 to 4 wherein the tube is constructed of metal. *t

6. A method of constructing a net wherein shock cord is threaded through mesh apertures in the net around the perimeter of the net, the two ends of the cord are joined according to any one of claims 1 to 5 and, at comers of the net, permanent loops are created in the cord by means of forming a bight in the cord and at the neck of the bight joining the portions of cord on each side of the bight according to any one of claims 1 to

7. A net comprising a rectangular panel of netting mesh material with a length of shock cord threaded through the peripheral mesh apertures around the perimeter of the panel, the cord having a permanent loop created therein at each of the four corners of the panel and the centre of each of the two shorter sides of the panel.

8. A net comprising a rectangular panel of netting mesh material with a length of shock cord threaded through the peripheral mesh apertures around the perimeter of the panel, the cord having a permanent loop created therein at each of the four corners of the panel and the centre of the two shorter sides of the panel, wherein each loop is created in the cord by means of forming a bight in the cord and at the neck of the bight joining the portions of cord on each side of the bight according to any one of claims 1 to

9. A net substantially as described in this specification with reference to the Figures.

10. A method ofjoining two lengths of shock cord substantially as described in this 1 specification with reference to the Figures.

11. A hanging storage container fitted to a generally vertical interior surface of a motor vehicle, said container being configured from a net according to claim 7 or 8, wherein said net is folded once so that the shock cord on said two shorter sides forms two vertical edges at each end of the container and the shock cord also forms two horizontal edges along the .o top of the container, the container having a single bottom edge formed by the fold in the oeo i mesh, and wherein the four top comers of the container are firmly attached to the vehicle by said loops at the four comers of the panel and the two bottom corners are firmly attached to the vehicle by the loops at the centres of the shorter sides. Dated this 24th day of November 2000 Netmakers Australia Pty Ltd by their patent attorneys Morcom Pemrnat