GB1591621A

GB1591621A - Life saving apparatus

Info

Publication number: GB1591621A
Application number: GB3492776A
Authority: GB
Original assignee: MITCHELL ARMADILLO Ltd FRANK
Current assignee: MITCHELL ARMADILLO Ltd FRANK
Priority date: 1977-11-21
Filing date: 1977-11-21
Publication date: 1981-06-24

Description

(54) IMPROVEMENTS IN OR RELATING TO LIFE SAVING APPARATUS (71) We, FRANK MITCHELL (ARMA DILLO) LIMITED of Woodvale Mills, Bradford Road, Brighouse in the County of York, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to life saving apparatus and more particularly, but not exclusively, to lifebuoys.

A conventional lifebuoy is usually formed from a ring of material which is buoyant in water such as, for example, cork or a rigid foam plastics material. These known materials from which lifebuoys have been formed suffer from the disadvantage that they have low inherent mechanical strength and are liable to crack and break if subjected to mechanical loading, particularly, impact loads which can occur when the lifebuoy is dropped onto a hard surface.

In order to overcome this problem which occurs when a lifebuoy is constructed from the above known materials, the ring of buoyant material forming the core of a conventional lifebuoy is covered with a wrapping of a canvas, polyvinylchloride, or polythene material to resist breakage of the lifebuoy, when it is subjected to impact loading.

However, the necessity of providing a wrapping for the core of a conventional lifebuoy decreases the buoyancy of the lifebuoy by adding to the weight thereof, and increases the time required to manufacture a lifebuoy which thus increases the cost thereof.

The object of this invention is to provide an improved life saving apparatus in which one or more of the above disadvantages are alleviated.

According to this invention, a life saving apparatus comprises a buoyant member formed of a semi-rigid thermosetting polymeric foam material, wherein at least 60% of the cells of the foam material are closed cells.

Preferably, the polymeric foam material is a polyurethane foam material. Preferably, also, the apparatus is in the form of a lifebuoy, and the buoyant member is a ring or, alternatively, the member may be of a horse-shoe shape.

The formation of the lifebuoy from a semirigid polyurethane foam material provides a lifebuoy which has a high resistance to breakage when subjected to impact loading thereby making the provision of a wrapping unnecessary, and the closed cell formation of the major portion of the material provides adequate buoyancy for the lifebuoy in water to enable it to support and act as a life saving device for a person in the water.

Preferably, a rope is attached to the periphery of the lifebuoy at spaced-apart attachment points thereon. Preferably, also, each attachment point is constructed by forming two recesses one on each side of the lifebuoy adjacent to the outer peripheral edge thereof and forming in the web of material remaining between the recesses, an aperture through which the rope is threaded.

The rope may be provided on each side of the aperture with a knot to restrict longitudinal movement of the rope through the aperture.

The lifebuoy is, preferably, coloured by pigmentation of the semi-rigid thermosetting polymeric foam material or, alternatively, the surface of the foam material may be painted with for example, a polyvinylchloride paint, or an acrylic paint. Approximately 90% of the cells of the foam material may be closed.

Preferably, the thermosetting foam material is formed from a polyol, an MDI type iso-cyanate, and a foaming or blowing agent.

The MDI type iso-cyanate may comprise diphenyl methane di-iso-cyanate, methylene bisphenyl di-iso-cyanate, or methylene diiso-cyanate.

Preferably, the thermosetting foam material is formed from 40 parts be weight of a copolymer comprising a polyether and one or more polyols, 2 parts by weight of amine catalyst and silicon surfactants, 8 parts by weight of fluro carbons and 50 parts by weight of methylene di-isocyanate.

A preferred embodiment of this invention will now be described, by way of example only, with reference to the accompanying drawings of which: Figure 1 is a plan view of a lifebuoy; and Figure 2 is a sectional side elevation on the line 11-Il in Figure 1 of the drawings.

Referring now to the drawings, a lifebuoy comprises a ring 10 of semi-rigid polyurethane foam material in which at least 60% of the cells of the foam material are closed cells.

It is preferred that approximately 90% of the cells of the foam material are closed cells in order to provide a lifebuoy with the greatest possible buoyancy in water for supporting a person, and the foam material is formed by combining a polyol with an MDI type isocyanate such as diphenyl methane diisocyanate or methylene bisphenyl di-isocyanate and a foaming or blowing agent so that they react together to produce the desired semi-rigid polyurethane foam material.

A particularly suitable foam material is produced by combining 40 parts by weight of a copolyment comprising a polyether and one or more polyols, 2 parts by weight of amine catalyst and silicone surfactants, 8 parts by weight of fluoro carbons, with 50 parts by weight of methylene di-isocyanate.

The particular constituents of the foam material are thoroughly mixed together and any pigments required added and are then inserted into a mould so that they combine and expand to take up the shape of the mould to form the ring 10 of the lifebuoy.

The ring 10 has recesses 12 formed therein during the moulding operation and the provision of these recesses 12 on each side of the ring 10 at the periphery thereof, produces a web 14 in which an aperture 16 is formed.

A rope 18 is threaded through each aperture 16 in each web 14 and knots 20 are formed in the rope 18 on each side of each aperture 16 to restrict the longitudinal movement of the rope 18 therethrough. The surface of the lifebuoy is coloured to make it easily visible during use by either the pigmentation of the semi-rigid polyurethane foam material during the mixing thereof as described above, or alternatively, the surface of the ring 10 is painted with a polyvinylchloride pairit, or an acrylic paint.

In a modification, the ring 10 of the lifebuoy is replaced by a substantially horseshoe shaped member formed of the semirigid polyurethane foam material, or any other suitable shape formed of the semi-rigid polyurethane foam material. The lifebuoy could, if required, be formed of a semi-rigid thermosetting polymeric foam material other than the polyurethane foam material described above.

WHAT WE CLAIM IS:- 1. A life saving apparatus comprising a buoyant member formed of a semi-rigid thermo setting polymeric foam material, wherein at least 60% of the cells of the foam material are closed cells.

2. A life saving apparatus according to Claim 1, wherein the polymeric foam material is a polyurethane foam material.

3. A life saving apparatus according to Claim 1 or Claim 2, wherein the apparatus is in the form of a lifebuoy.

4. A life saving apparatus according to Claim 3, wherein the buoyant member of the lifebuoy is in the form of a ring.

5. A life saving apparatus according to Claim 3, wherein the buoyant member of the lifebuoy is of a horse-shoe shape.

6. A life saving apparatus according to any one of Claims 3 to 5, wherein a rope is attached to the periphery of the lifebuoy at spaced-apart attachment points thereon.

7. A life saving apparatus to Claim 6, wherein each attachment point is constructed by forming two recesses one on each side of the lifebuoy adjacent to the outer peripheral edge thereof and forming in the web of the material remaining between the recesses, and aperture through which the rope is threaded.

8. A life saving apparatus according to Claim 7, wherein the rope is provided on each side of the aperture with a knot to restrict longitudinal movement of the rope through the aperture.

9. A life saving apparatus according to any one of Claims 3 to 8, wherein the lifebuoy is coloured by pigmentation of the semi-rigid thermosetting polymeric foam material.

10. A life saving apparatus according to any one of Claims 3 to 8, wherein the lifebuoy is coloured by painting the surface of the semi-rigid thermosetting folymeric material with a polyvinylchloride paint, or an acrylic paint.

11. A life saving apparatus as claimed in any one of the preceding claims, in which approximately 90% of the cells of the semirigid thermosetting polymeric foam material are closed.

12. A life saving apparatus as claimed in any one of the preceding claims, in which the thermosetting material is formed from a polyol, an MDI type iso-cyanate, and a foaming or blowing agent.

13. A life saving apparatus as claimed in claim 12, in which the Mdi type iso-cyanate comprises diphenyl methane di-iso-cyanate, methylene bisphenyl di-iso-cyanate, or methylene di-iso-cyanate.

14. A life saving apparatus as claimed in any one of the Claims 12 or 13, in which the thermosetting foam material is formed from 40 parts by weight of a co-polymer comprising a polyether and one or more polyols, 2 parts by weight of amine catalyst and silicon surfactants, 8 parts by weight of fluorocarbons and 50 parts by weight of methylene di

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. will now be described, by way of example only, with reference to the accompanying drawings of which: Figure 1 is a plan view of a lifebuoy; and Figure 2 is a sectional side elevation on the line 11-Il in Figure 1 of the drawings. Referring now to the drawings, a lifebuoy comprises a ring 10 of semi-rigid polyurethane foam material in which at least 60% of the cells of the foam material are closed cells. It is preferred that approximately 90% of the cells of the foam material are closed cells in order to provide a lifebuoy with the greatest possible buoyancy in water for supporting a person, and the foam material is formed by combining a polyol with an MDI type isocyanate such as diphenyl methane diisocyanate or methylene bisphenyl di-isocyanate and a foaming or blowing agent so that they react together to produce the desired semi-rigid polyurethane foam material. A particularly suitable foam material is produced by combining 40 parts by weight of a copolyment comprising a polyether and one or more polyols, 2 parts by weight of amine catalyst and silicone surfactants, 8 parts by weight of fluoro carbons, with 50 parts by weight of methylene di-isocyanate. The particular constituents of the foam material are thoroughly mixed together and any pigments required added and are then inserted into a mould so that they combine and expand to take up the shape of the mould to form the ring 10 of the lifebuoy. The ring 10 has recesses 12 formed therein during the moulding operation and the provision of these recesses 12 on each side of the ring 10 at the periphery thereof, produces a web 14 in which an aperture 16 is formed. A rope 18 is threaded through each aperture 16 in each web 14 and knots 20 are formed in the rope 18 on each side of each aperture 16 to restrict the longitudinal movement of the rope 18 therethrough. The surface of the lifebuoy is coloured to make it easily visible during use by either the pigmentation of the semi-rigid polyurethane foam material during the mixing thereof as described above, or alternatively, the surface of the ring 10 is painted with a polyvinylchloride pairit, or an acrylic paint. In a modification, the ring 10 of the lifebuoy is replaced by a substantially horseshoe shaped member formed of the semirigid polyurethane foam material, or any other suitable shape formed of the semi-rigid polyurethane foam material. The lifebuoy could, if required, be formed of a semi-rigid thermosetting polymeric foam material other than the polyurethane foam material described above. WHAT WE CLAIM IS:-

1. A life saving apparatus comprising a buoyant member formed of a semi-rigid thermo setting polymeric foam material, wherein at least 60% of the cells of the foam material are closed cells.

isocyanate.

15. A life saving apparatus constructed and arranged substantially as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.