GB1574093A

GB1574093A - Protective cover

Info

Publication number: GB1574093A
Application number: GB1521977A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-04-12
Filing date: 1978-04-12
Publication date: 1980-09-03

Description

(54) -PROTECnVE COVER (71) I, HAROLD HORNBY, a British Subject, of 43 Caiystane Avenue, Edinburgh 10, Scotland, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to thermal insulating material, particularly material for insulating sports fields, such as football pitches, against frost. While the material has many other uses for insulating surfaces other than sports fields, it will for simplicity be described in connection therewith.

It has been proposed heretofore to protect sports fields by the use inter alia of straw, of heated air blown under a cover, or of electrical heating elements embedded in the ground. The disadvantages of these prior proposals are that they are expensive and/or time consuming to use.

It has also been proposed to provide a thermal insulation mat or blanket having two superposed layers of flexible plastics sheets welded together to form a plurality of closed pockets each being wholly substantially filled with at least one sheet of expanded polystyrene. Such a mat or blanket is, however, foldable only along the welded joins between the pockets.

The primary object of the present invention is to obviate or mitigate these disadvantages.

According to the present invention, thermal insulating material comprises a flexible plastics cover, and at least one layer of an insulating composition hermetically sealed within the cover, air being trapped between adjacent faces of said layer and said cover, said cover, in conjunction with said layer, being sufficiently rigid that while said material may be folded in itself substantially anywhere along its length or breadth it will remain substantially flat when unfolded.

Two embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: - Figs. 1 and 2 are respectively transverse cross-sections of the first and -second embodiments.

Referring to Fig. 1 of -the drawings a cover consists of two plies 1, 2 of woven and laminated polyethylene sheeting of the same width and length laid one - on -top - of the other. The inner face of the ply 2 is coated with a layer 3 of polyethylene foam extending to the edges and ends of the-ply 2. The contiguous edges and end portions of the plies are thermal-welded all round at 4, with the edges and ends of the layer 3 sandwiched between the plies 1, 2, so that the cover as a whole is air-tight and waterproof, with the layer hermetically sealed within the cover.

The sheeting is of woven 10 x l0-mesh and each lamination ply is 0 05- mm thick.

The layer 3 is 2 mm thick.

The cover is 74 metres long and 18 metres in width, i.e. a ratio of length to width in excess of 4:1.

The characteristics and properties of the insulating material as a whole are substantially unchangeable within a temperature range of from --28"C to +70 C, arid the flexing resistance, acid and alkali resistanee and oil resistance are substantially unchangeable.

The plies 1, 2 of sheeting- betweens which there is air, air also being present in the interstices of the layer 3, serve not only for insulating purposes.but, in combindtion with the layer 3, also serve to- impart rigidity to the insulating material- as a whole so that the material will lie flat and may be walked on when laid on a field.

In practice, the insuldting-material which is of a length slightly.in- excess of the width of a sports field, such as a football pitch is sufficiently flexible to be folded on itself substantially anywhere along its - length or breadth to provide a compact bundle which may be readily handled. When it is desired to cover a football pitch to- insulate the field against' frost, the folded--material is placed, for example, on one side of the field beyond the associated touch line and is then unfolded to extend across the field to a point beyond the opposite touch line.

This is repeated with other identical bundles of insulating material which are unfolded and laid side by side, but slightly overlapping, in strips until the whole field is covered. To uncover the field, the strips are simply folded and removed for storage.

As the plies 1, 2 of sheeting are hermetically sealed together and there is air not only between the plies but in the interstices of the layer 3, the protective cover will insulate the field adequately against frost.

The material is relatively inexpensive to produce and being foldable for ready handling and storage provides a relatively inexpensive way of insulating a sports field.

Also should the outer cover be damaged, a patch may be readily applied to the cover by heat-sealing where the damage in the polyethylene has occurred.

The layer 3 is in effect laminated to the ply 2 and this will in itself create a corrugation effect as the cover is rolled up for storage. The undulating folds will form air passages which will inhibit any fungus growth forming from deposits of soil that may cling to the cover after lifting from a field.

Referring to Fig. 2 a cover consists of a tube 5 of heavy duty, but flexible, polyethylene, substantially of the same lateral and longitudinal dimensions as the cover illustrated in Fig. 1. Laid Aat within the cover 5 one on top of the other there are two plies 6, 7 of an insulating composition.

The plies 6, 7 fill the cover and serve also to flatten the insulating material as a whole when laid on the ground.

The ends of the tube 5 are heat-sealed together so as to seal the plies 6, 7 hermetically within the cover.

The plies 6, 7 between which there is air.

air also being present between the plies and the cover, serve not only for insulation purposes but also serve to impart rigidity to the insulating material as a whole so that the material may be walked on when laid on the ground.

The plies 6, 7 illustrated in Fig. 2 are of a paper composition, such as that known as lapping paper.

In a modification, the plies 6, 7 are of glass fibrous material.

In a further modification, the plies 6, 7 each consist of a combination of paper and glass fibrous material.

In yet a further modification, the plies 6, 7 are of flexible corrugated material.

preferably corrugated paper. In use, air is trapped not only between adjacent faces of the paper and the cover, but also within the corrugations of the paper. Should the corrugations become flattened in use of the cover, there will still be sufficient air within the corrugations to ensure that the cover as a whole retains its insulating properties.

While paper is the preferable material, corrugated material having similar'proper- ties to those of corrugated paper may be used instead of paper.

The insulating material, described with reference to Fig. 2 and the modifications thereof, is used to protect a sports field in the same manner as the material described with reference to Fig. 1.

It will be understood that the plastics material described with reference to Figs.

1 and 2 may be replaced by other plastics material than those specifically described provided that the material is flexible so as to -be capable of being rolled into a bundle and unrolled into a flat condition.

WHAT I CLAIM IS: - 1. Thermal insulating material comprising a flexible plastics cover, and at least one layer of an insulating composition hermetically sealed within the cover, air being trapped between adjacent faces of said layer and said cover, said cover, in conjunction with said layer, being sufficiently rigid that while said material may be folded on itself substantially anywhere along its length or breadth it will remain substantially flat when unfolded.

2. Material as claimed in Claim 1 in which the cover consists of two plies of plastics sheeting laid one on top of the other, and a layer of a flexible plastics foam coating the inner face of one of said plies, the contiguous edges and end portions of the plies being heat-sealed together.

3. Material as claimed in Claim 1 or 2 whose longitudinal dimensions are considerably in excess of its lateral dimensions.

4. Material as claimed in Claim 3 the ratio of the longitudinal dimensions to the lateral dimensions of which is in excess of 4:1.

5. Material as claimed in Claim 2 in which the sheeting and the plastics foam are of polyethylene.

6. Material as claimed in Claim 1 in which the cover contains two layers or plies of an insulating composition laid one on top of the other in such wise that there is air between the plies and between the plies and the cover.

7. Material as claimed in Claim 6 in which the composition is paper.

8. Material as claimed in Claim 6 in which the composition is glass fibrous material.

9. Material as claimed in Claim 6 in

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. is placed, for example, on one side of the field beyond the associated touch line and is then unfolded to extend across the field to a point beyond the opposite touch line. This is repeated with other identical bundles of insulating material which are unfolded and laid side by side, but slightly overlapping, in strips until the whole field is covered. To uncover the field, the strips are simply folded and removed for storage. As the plies 1, 2 of sheeting are hermetically sealed together and there is air not only between the plies but in the interstices of the layer 3, the protective cover will insulate the field adequately against frost. The material is relatively inexpensive to produce and being foldable for ready handling and storage provides a relatively inexpensive way of insulating a sports field. Also should the outer cover be damaged, a patch may be readily applied to the cover by heat-sealing where the damage in the polyethylene has occurred. The layer 3 is in effect laminated to the ply 2 and this will in itself create a corrugation effect as the cover is rolled up for storage. The undulating folds will form air passages which will inhibit any fungus growth forming from deposits of soil that may cling to the cover after lifting from a field. Referring to Fig. 2 a cover consists of a tube 5 of heavy duty, but flexible, polyethylene, substantially of the same lateral and longitudinal dimensions as the cover illustrated in Fig. 1. Laid Aat within the cover 5 one on top of the other there are two plies 6, 7 of an insulating composition. The plies 6, 7 fill the cover and serve also to flatten the insulating material as a whole when laid on the ground. The ends of the tube 5 are heat-sealed together so as to seal the plies 6, 7 hermetically within the cover. The plies 6, 7 between which there is air. air also being present between the plies and the cover, serve not only for insulation purposes but also serve to impart rigidity to the insulating material as a whole so that the material may be walked on when laid on the ground. The plies 6, 7 illustrated in Fig. 2 are of a paper composition, such as that known as lapping paper. In a modification, the plies 6, 7 are of glass fibrous material. In a further modification, the plies 6, 7 each consist of a combination of paper and glass fibrous material. In yet a further modification, the plies 6, 7 are of flexible corrugated material. preferably corrugated paper. In use, air is trapped not only between adjacent faces of the paper and the cover, but also within the corrugations of the paper. Should the corrugations become flattened in use of the cover, there will still be sufficient air within the corrugations to ensure that the cover as a whole retains its insulating properties. While paper is the preferable material, corrugated material having similar'proper- ties to those of corrugated paper may be used instead of paper. The insulating material, described with reference to Fig. 2 and the modifications thereof, is used to protect a sports field in the same manner as the material described with reference to Fig. 1. It will be understood that the plastics material described with reference to Figs.

7. Material as claimed in Claim 6 in which the composition is paper.

9. Material as claimed in Claim 6 in

which the composition is a combination of paper and glass fibrous material.

10. Material as claimed in Claim 6 in which the composition is of flexible corrugated material.

11. Thermal insulating material substantially as herein described and as illustrated by Fig. 1 or Fig. 2 of the accompanying drawings.