GB2287911A

GB2287911A - Floatable platforms

Info

Publication number: GB2287911A
Application number: GB9506357A
Authority: GB
Inventors: James Mclachlan
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-03-30
Filing date: 1995-03-28
Publication date: 1995-10-04
Anticipated expiration: 2015-03-28
Also published as: GB2287911B; GB9406402D0; GB9506357D0

Abstract

A floatable platform from which fish retaining nets 10 may be suspended, and which provides walkways around the netted areas is formed from a series of buoyancy members 4, 6, 8 which are linked together by means of cables or chains 18 which pass through inserts received in passageways 16 formed in the members 4, 6, 8. Selected ones of these members 6 are provided with adjustable inserts 34 which are arranged to reduce in length as the cables or chains 16 are tensioned, thus conferring rigidity on the platform assembly. The adjustable inserts 34 comprise two portions 36, 38, with resiliently compressible means, e.g. a spring (42), positioned therebetween. <IMAGE>

Description

FLOATABLE PLATFORMS The invention is concerned with improvements in or relating to floatable platforms, particularly but not exclusively, incorporating tread surfaces for use as walkways for access to sub-surface equipment such as nets.

In the maintenance of such equipment in the presence of water it is essential to provide access for personnel which is convenient and conforms with all relevant safety regulations. For example, in the farming of fish, usually salmon or trout, it is customary to enclose a number of fish within net compartments suspended beneath floats positioned at edges of the net compartments. Conveniently where the floats are for example box-like, these may be linked together to form walkways. It is obvious that such a walkway should be relatively rigid as well as buoyant enough to maintain the netting of the compartments in an outspread condition.

The invention therefore provides a floatable platform suitable for use as a walkway, said platform comprising a plurality of buoyancy members arranged in a desired sequence so that each member is at least substantially adjacent to one or more neighbouring buoyancy members and fastening cable means adapted to link said buoyancy members wherein said buoyancy members are provided with through passageways for the passage of said fastening cable means, means are provided to impart tension to said cable means in said passageways, at least selected ones of said buoyancy members being provided with a plurality of hollow, adjustable inserts adapted to be received in the passageway(s) thereof and through which said fastening cables pass, said adjustable inserts having at least one axially resilient portion so as to be reducible in length as said cables are placed under tension.

Preferably, other, intervening, ones of said buoyancy members may be provided with rigid inserts within said passageways, said cable means comprising chains passing through said inserts within the passageways.

Advantageously, said adjustable inserts comprise a plurality of insert portions including at least one rigid body portion adapted to protrude from said passageway when said fastening cables are untensioned and an axially resiliently mounted end portion, the reduction in length of which insert permits said rigid body portion to be withdrawn so as to be at least substantially received in said passageway.

Advantageously, each said adjustable insert may comprise two insert portions that are rigid and an intermediate, axially resilient portion. Conveniently, the resilient insert portion may be, for example, a spring such as a compression spring, a resilient foam plastics sleeve, or any other suitable means.

Conveniently, one of the rigid insert members may have a tapered outer end portion adapted to engage a tapered recess of an insert of a neighbouring buoyancy member.

In an example of a buoyancy member to be described below, an end portion of one of said rigid insert portion is telescopically received within the second rigid insert portion with the resilient portion interposed therebetween.

There will now be described an example of a floatable platform according to the invention. It will be understood that the description, which is to be read with reference to the drawings, is given by way of example only and not by way of limitation.

In the drawings: Figure 1 shows a part of a fish farm floatable platform; Figure 2 is a portion of the platform of Figure 1 showing linking cables; Figure 3 shows a buoyancy member having a rigid insert; Figure 4 is a exploded perspective view of a buoyancy member having an axially compressible insert; Figure 5 is a cross-section through the assembled insert of Figure 4; and Figure 6 is an arrangement of a corner buoyancy member.

Figure 1 shows a part of a fish farm arrangement having a floating platform 2 comprising a plurality of buoyancy members 4, 6, 8 arranged in a side-by-side manner to form elongate platform portions which provide framework for a number of net containers 10 for the fish being farmed. Each buoyancy member is provided with a tread surface 12 and the platform is provided with handrails 14 secured at intervals to the buoyancy members. Each member 4 and 6 has two passageways 16 (Fig. 2) therethrough each of which receives a cable 18.

In the present example, the cable 18 is in the form of a chain. The buoyancy members are of moulded plastics material and have air-filled cavities.

In assembly of the platform, a series of buoyancy members are linked, as shown, by the chains 18 and at the corner or junction buoyancy members 8 of the platform, the chains are secured by lock-pins 20 after being tensioned as explained below.

Figure 3 shows a standard buoyancy member 4 which is a hollow moulded plastics enclosure having a air-filled cavity. The passageways 16 formed through the member 4 have recesses 22 at mouth portions thereof, which recesses receive end flanges 24 of hollow insert members 26 through which in use the chains 18 pass. In addition, each insert member 26 has a tapered end portion 30 which is received in an end portion 32 of the corresponding insert 26 of the neighbouring member.

Intervening between the members 4 in the string of buoyancy members are the members 6, which are illustrated in Figures 4 and 5.

Each buoyancy member 6 is similarly formed as a moulded plastics enclosure with passageways 16 therethrough. The construction of insert members 34 received in the passageways is such that the overall length of the inserts is reducible from a condition in which the insert members project from their respective passageways to a condition in which they are almost completely received therewithin. Each insert 34 thus comprises a main rigid body portion 36 and a rigid end portion 38 adapted to slide over the inner end of the portion 36 by a small, variable, distance. The end portion 38 is formed by a hollow sleeve having an inwardly turned annular flange 40. A compression spring 42 is captive between flanges 37 and 39 of the portions 36 and 38 and produces the desired resilience and capability to bring about a change in overall length of the insert member 6. The two inserts 34 are yoked together by a strut 28 which supports upright members of the hand rails 14.

The corner members 8 are conveniently constructed in two separate mouldings as shown in Figure 6. Each moulding 8a, 8b carries a portion of the tread surface 12 and is recessed at 46. An insert assembly constructed from four long inserts 26 arranged in the desired formation and inserted into jointing devices or knuckles 50, and then received in the recesses of the members 8a, 8b as the two portions 8a and 8b are brought together and held in place by the chains 16 passing through the inserts 26.

In assembly, the chains 18 are used to support all of the members 4, 6 and 8 strung thereon under initially slack tension, ensuring that the members are arranged so that tapered end portions 30 confront the recesses 32 of the neighbouring member 4, 6 and 8.

It will be found convenient to apply tension to the chains 18 as the assembly is placed on the water where it is to float. When the desired tension is achieved, the insert members of the buoyancy members 6 have been axially compressed and the platform formed by the members 4, 6 and 8 is rigid, the chains 18 are fastened at the members 8 by lock pins 20 as previously mentioned. The nets 10 are then attached and the handrails 14 secured.

Various modifications may be made within the scope of the invention as defined in the following claims.

Claims

CLAIMS:

1. A floatable platform for use as a walkway, said platform comprising a plurality of buoyancy members arranged in a desired sequence so that each member is at least substantially adjacent to one or more neighbouring buoyancy members and fastening cable means adapted to link said buoyancy members wherein said buoyancy members are provided with through passageways for the passage of said fastening cable means, means are provided to impart tension to said cable means in said passageways, at least selected ones of said buoyancy members being provided with a plurality of hollow, adjustable inserts adapted to be received in the passageway(s) thereof and through which said fastening cables pass, said adjustable inserts having at least one axially resilient portion so as to be reducible in length as said cables are placed under tension.

2. A platform as claimed in claim 1, wherein further ones of said buoyancy members are provided, having rigid inserts within said passageways, said cable means comprising passing through said inserts within the passageways.

3. A platform as claimed in either one of claims 1 and 2, wherein said adjustable inserts comprise a plurality of insert portions including at least one rigid body portion adapted to protrude from said passageway when said fastening cables are untensioned and an axially resiliently mounted end portion, the reduction in length of which insert permits said rigid body portion to be withdrawn so as to be at least substantially received in said passageway.

4. A platform as claimed in claim 3, wherein each said adjustable insert comprises two insert portions that are rigid and an intermediate axially resilient portion.

5. A platform as claimed in claim 4, wherein said axially resilient portion comprises a spring, preferably a compress ion spring.

6. A platform as claimed in claim 4, wherein said axially resilient portion comprises a resilient foam plastics sleeve.

7. A platform as claimed in any one of the preceding claims, wherein said rigid insert members have a tapered outer end portion adapted to engage a tapered recess of an insert of a neighbouring buoyancy member.

8. A platform as claimed in any one of the preceding claims, wherein there is provided hand rail means to be secured to the platform, a strut being provided to yoke together two side-by-side inserts of said buoyancy members to provide a support for said hand rail means.

9. A platform as claimed in any one of the preceding claims, wherein there are further provided corner or junction buoyancy members adapted to permit changes of direction of the path of said walkway, said corner members being provided with jointing means adapted to secure together intersecting ones of said inserts to maintain them in portion.

10. A floatable platform suitable for use as a walkway, constructed and arranged substantially as hereinbefore described with reference to and as shown in the drawings.