GB2187921A

GB2187921A - Nets

Info

Publication number: GB2187921A
Application number: GB08625799A
Authority: GB
Inventors: George Renton
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-11-09
Filing date: 1986-10-29
Publication date: 1987-09-23
Also published as: GB8625799D0

Abstract

A net has the netting material connected at an open end to a flexible tube adapted to be pressurised from a fluid source, whereby with the tube pressurised, the periphery of the open end of the net assumes the profile of the pressurised tube. The net may be used in fishing or be a football or like net. <IMAGE>

Description

SPECIFICATION Improvements in fishing nets This invention relates to fishing nets and the like.

A number of techniques exist in using nets to catch fish and like sea produce. All these techniques have in common the exposure of the largest possible area of net to provide the maximum swept volume of water and hence potential catch, while reducing to a minimum the area of net and loss of catch when the net is cast or is drawn in board onto a fishing vessel or the like.

It is an object of the present invention to produce a fishing net which better meets these criteria.

The present invention according to its broadest aspect provides a flexible tube connectible to a pressurised fluid source, a net or nets being secured to the tube whereby with the tube pressurised from the fluid source, a periphery of the net assumed the profile of the pressurised tube.

By the use of the present invention a net of intrinsically large area can be tensioned to provide a large sweeping area by pressurising the tube to which the net is secured. Equally the net can be reduced to a relatively small area enabling it to be cast from or retrieved by a fishing vessel or the like by releasing the fluid pressure within the net retaining tube.

Suitably the fluid is a gas such as air which may be obtained from a pressurised source such as compressed gas cylinder or pump.

Alternatively the fluid may be a liquid which may be obtained from a pressure source such as a pump.

In a preferred embodiment of the invention where the fluid source is a pump, the pump is reversible so as to be capable of partially or fully exhausting the tube of liquid whereby to induce a greater degree of collapse and further reduce the overall area of the net during casting or retreaval.

In the case where the net retaining tube is pressurised by gas such as air, the net retaining tube may be suitably weighted to compensate for the effects of buoyancy in accordance with the depth at which the net is to be used.

Alternatively where the net retaining tube is pressurised by a liquid such as water, buoyancy devices may be provided to maintain the tube and the net as the required depth.

The net retaining tube may be of any flexible material such as rubber, neoprene or any suitable plastics material adapted to withstand the fluid pressure required to keep the selected length of tube substantially rigid and to withstand the tension of casting and towing lines.

The fishing net of the present invention may be towed and retreaved by means of a towing line or lines suitably secured to appropriate portions of the tube periphery. A feed tube for pressurising and/or exhausting the net supporting tube may be secured to one of the towing lines to provide greater suitability.

The net retaining tube of the present inven-.

tion may be arranged to assume any required shape. A circumferentially continuous flexible tube will when pressurised assume a substantially circular profile which will represent the swept volume of the fishing net. Alternatively, however, flexible poertions of the tube may be replaced by rigid portions for example of metal or rigid plastics or the like adapted to produce other profiles. For example, four right angled rigid tubes connecting linear portions of flexible tube will induce a rectangular tube periphery during pressurisation.

An embodiment of the invention will now be particularly described with reference to the accompanying drawing which illustrates a fishing net adapted for bottom trawling.

Referring to the drawing, the fishing net arrangement indicated generally at 2, comprises four right angled rigid metal tubes 4, which are used to connect four lengths of substantially linear PVC thick walled tubes 6 and 8 capable of withstanding substantial fluid pressure. The tubes 6 are longer than the tubes 8 so that the combination of flexible tubes and right angled metal tubes 4 tend to form a rectangle when internally pressurised. A tube 10 connected conveniently to one of the angled metal tubes 4 communicates with a gas pressure source such as a gas or air cylinder or a reversible air pump (not shown).

The cylinder or the pump will be retained inboard of the vessel utilising the net of the present invention.

Suitably secured to the frame produced by the combination of pressurised flexible tubes 6, 8 and metal tubes 4 is a fishing net indicated generally at 12. The fishing net has an open end at the frame which it is secured at spaced intervals and a closed opposite end.

By this means, when the net is drawn or trawled through the water, fish or other sea produce entering the open end will be positively caught.

A number of tow lines 14 secured to the frame but preferably to the metal tubes 4 is effective to tow or trawl the net through the water. The pressurising feed tube 10 is preferably secured to one of the tow lines.

In use of the net accordingly to the present invention and with tubes 6 and 8 at atmospheric or below atmospheric pressure, the net together with its supporting frame can be collapsed into a relatively small area and volume as a result of the flexibility of the tubes.

The net can be cast overboard in this condition and expanded into the configuration shown in the Figure by pressurising the frame from a gas cylinder or from an air or water pump. In this condition the net can be used for fishing or trawling by way of the two lines 14.

At the conclusion of fishing the pressure in the tubes 6 and 8 may be released and optionally reduced to below atmospheric pressure in the case where a reversible pump is used for pressurising. In both these cases the frame retaining the net 12 will collapse to a relatively small area partly as a result of evacuation and partly by tension in the tow lines 14.

Such collapse of frame area not only assists loss of catch but also simplifies hauling the netjframe combination in board of the fishing vessel and the like.

It will be appreciated that the invention provides a fishing net of relatively large catching area which can occupy a relatively small volume for storage and ease of casting and hauling inboard and retrieval.

It will also be appreciated that while the invention has been described with reference to a net having a rectangular catching area, other shapes and configurations may be employed.

Equally, suitably pressurised flexible tubes may also be additionally used to give a degree of rigidity and shape to parts of the net other than that illustrated in the drawing.

It will equally be appreciated that rectangular or other non circular net shapes can be provided by metal cramps of suitable shapes which are secured around the periphery of selected portions of the tube and which constrain those portions to the shape of the cramps. In this way a net of non circular catching area can be produced with a substantially continuous length of flexible tube.

It will also be appreciated that while the present invention has been described with reference to fishing nets, it is equally applicable to other nets such as football and like nets, holding nets and like which can be collapsed to a small volume when not in use.

Claims

1. A net, in which the netting material is connected at an open end to a flexible tube adapted to be pressurised from a fluid source, whereby with the tube pressurised, the periphery of the open end of the net assumes the profile of the pressurised tube.

2. A net as claimed in claim 1, wherein the netting material is closed at another end and is adapted for fishing.

3. A net as claimed in claim 2, wherein the tube is adapted when pressurised to assume a rectangular profile.

4. A net as claimed in claim 2, wherein the tube is adapted when pressurised to assume a circular profile.

5. A net as claimed in any of the claims 1 to 4, wherein the tube profile when pressurised is controlled by flexible portions interconnected by solid portions.

6. A net as claimed in any preceding claim, wherein the tube profile is controlled by solid cramps secured around flexible portions of the tube.

7. A net as claimed in any one of claims 2 to 6, wherein weights are provided to cause the net to sink.

8. A net as claimed in any one of claims 2 to 6, wherein buoyancy devices are provided to cause the net to float.

9. A fishing net substantially as herein described with reference to the accompanying drawing.

10. A fishing net substantially as shown in, and adapted to operate substantially as herein described with reference to, the accompanying drawing.

11. The combination of a tube pressurising source and a net as claimed in any preceding claim.

12. A net as claimed in claim 1 and substantially as herein described.