GB2344737A

GB2344737A - Inflatable arm-bands for swimming

Info

Publication number: GB2344737A
Application number: GB9827486A
Authority: GB
Inventors: Howard Watts
Original assignee: WET SPORTS Ltd
Current assignee: WET SPORTS Ltd
Priority date: 1998-12-15
Filing date: 1998-12-15
Publication date: 2000-06-21
Anticipated expiration: 2018-12-15
Also published as: GB2344737B; GB9827486D0

Abstract

An arm-band which can be rolled up the user's arm when inflated comprises first and second separate air chambers A, B each extending around a wearer's arm in use and having a common wall 12. The potential inflated volume of the first chamber A is roughly half that of the second chamber B but the construction of the arm-band is such that if the first chamber A is fully inflated prior to inflation of the second chamber B, the inflated volumes of the two chambers will be roughly equal. The band may be made by welding the wall 12 around its edges to a larger sheet, folding and seaming the larger sheet to form a tube, partly everting the tube and seaming again.

Description

ARM-BANDS The invention relates to inflatable arm-bands for use as swim aids.

Arm-bands for use as swim aids by small children are well known. One common type consists of two separate inflatable chambers which are located in series with a flat web of material to form a ring which fits around the arm with the flat web between the arm and the body. Regulations require that two chambers are provided so that some assistance will still be given if one of the chambers becomes deflated. With this type of arm-band, it is necessary to inflate the chambers after fitting to the arm and to deflate for removal.

A less well known arm-band is formed with two chambers having a common wall and which both extend around the user's arm. This type of arm-band can be rolled up the arm of the user after inflation. Whilst two chambers are provided, the first chamber has been provided with a maximum inflatable volume of about 10% of that of the second chamber and if the second chamber is inflated first, the volume to which the first chamber can then be inflated will be even less than 10% of the volume of the second chamber.

The object of the invention is to provide an arm-band of the roll up type which when correctly inflated provides an arm-band having two chambers of roughly equal volume.

Accordingly the invention provides a method of forming an inflatable arm-band comprising the steps of : providing a first rectangular sheet of material having top, bottom, right and left sides, an inner surface, and an outer surface ; laying a second rectangular sheet of material on the inner surface of the first sheet and seaming the two sheets together around the sides of the second sheet to form a first sealed chamber between the first and second sheets; seaming the top and bottom sides of the first sheet together to form a tube; partially everting the tube such that the left and right sides of the first sheet are adjacent one another and the outer surface of the first sheet forms the outer surface of the partially everted tube; sealing the left and right sides of the first sheet together to form a second sealed chamber; and providing first and second valves in the first sheet for inflation of the first and second chambers respectively, wherein the height of the second sheet is the same as or slightly less than that of the first sheet and the width of the second sheet is such that if the first chamber is fully inflated prior to inflation of the second chamber, the inflated volumes of the two chambers is roughly equal.

The invention also provides an arm-band comprising first and second separate air chambers each extending around a wearer's arm in use and having a common wall ; wherein the potential inflated volume of the first chamber is roughly half that of the second chamber but wherein the construction of the arm-band is such that if the first chamber is fully inflated prior to inflation of the second chamber, the inflated volumes of the two chambers will be roughly equal.

An embodiment of the invention is described below with reference to the accompanying drawings, in which : Figure 1 is a plan view of a first sheet of material used in making an arm-band; Figure 2 is a plan view of the first sheet of material of Figure 1 with a second sheet of material seamed thereto; Figure 3 is a perspective view of the sheets of material formed into a tube; Figure 4 is a cross-section of the tube of Figure 3 after it has been partially everted ; Figure 5 is a vertical cross-section, on a slightly larger scale, of an arm-band when located on an arm; and Figure 6 is a horizontal cross-section taken on the line VI-VI of Figure 5.

Referring to the drawings, the arm band is constructed as follows. A first rectangular sheet of plastic waterproof material 1 having a top side 2, a bottom side 3, a right side 4 and a left side 5 is provided and has an inner surface 6 and an outer surface 7.

Two apertures 8,9 are formed in the sheet and valves 10,11 are fitted to the holes on the outer side of the sheet. The sheet 1 has a width W and a height H.

A second rectangular sheet 12 of plastic waterproof material 12, having a width w and a height h, is then laid onto the inner surface 6 of the first sheet and seamed around its sides to the second sheet by welding. This forms a first sealed chamber A between the first and second sheets. The height h is the same or slightly less (as shown) than the height H The sheet 1 is then folded in half so that the sides 2 and 3 are adjacent each other and are seamed together along a linear seam 13 by welding. This forms a tube 14 as shown in Figure 3, with the inner surface 6 of the sheet 1 forming the outer surface of the tube The tube 14 is then partially everted to the position shown in Figure 4 in which the folded sides 4 and 5 are adjacent to each other and are seamed together along a circular seam 15 by welding. The forms a second sealed chamber B The chambers A and B are now in the form of tubular rings extending round the axis 16 of the arm band and can be inflated through the valves 10 and 11 respectively. Chamber A does not form a continuous ring but has an interruption where the ends of the sheet 12 are welded to the sheet 1.

The chambers have a common wall provided by the second sheet 12 and, when inflated, form an arm-band which can be rolled onto an arm as shown in Figures 5 and 6.

If the second chamber B were to be fully inflated prior to inflation of the first chamber A, inflation of the first chamber A would be substantially prevented. If the first chamber A is fully inflated prior to inflation of the second chamber B, however, only a part of the potential volume of the second chamber B is taken up by the first chamber A so the second chamber B can still be inflated to the remaining part of its potential volume It is desired that when the arm band is inflated in use, the inflated volume of the first chamber A is roughly equal to the inflated volume of the second chamber B. This can be achieved if the potential volume of the second chamber B is twice the potential volume of the first chamber A and the first chamber A is fully inflated prior to inflation of the second chamber B.

Considering the view of the arm band shown in Figure 5, the second chamber B can be considered as a tube extending around the arm having a maximum (circular) crosssectional area of sR2 where R is the radius of the circle whose circumference is W.

Similarly, the first chamber can be considered as a tube extending around the arm and having a maximum (circular) cross-sectional area of where r is the radius of the circle whose circumference is 2w. Since the maximum fully inflated volume of the second chamber is to be twice that of the maximum fully inflated volume of the second chamber the desired relationship gives 7tR2 = 27tr2 substituting for R as W and for r as w 2 7t we get W2 = 8w2 W = 22w or w = W 242 so w= 0. 354 W Thus it is calculated that the ideal result can be achieved if the width w of the second sheet is about 35% of the width W of the first sheet. If the width of the second sheet is between 30% and 40% of the width of the first sheet a very useful result is obtained and a useful result can be obtained if the width of the second sheet is between 25% and 50% of the width of the first sheet.

When the arm band is inflated, the valves 10,11 can be recessed in known way so that the arm band can roll easily up the arm of the user and can come to rest with the chambers in the relative position shown in Figures 5 and 6 or any other relative position.

It is very important that the chambers A and B are inflated in the correct order and to this end, the valves 10 and 11 are distinguished by an indicator adapted to identify which connects to the chamber which must be inflated first For example, the valves may have different colours or may be marked with numerals"1"and"2"or letters"A"and"B" Instructions for inflating the chambers of the arm-band in the correct order will be printed on the outer surface of the arm-band.

Referring to Figure 6, it can be seen that the part of the sheet 1 which at any one time forms the inner surface of the inflated arm-band which lies against the arm will be deeply creased or wrinkled since it has the same circumferential length as the outer surface at that time. This length is equal to the height H of the original sheet 1 The sheet 12 will also be creased as shown in Figure 6 since it has a circumferential length equal to the height h which is only slightly less than the height H.

Claims

CLAIMS 1. A method of forming an inflatable arm-band comprising the steps of providing a first rectangular sheet of material having top, bottom, right and left sides, an inner surface, and an outer surface; laying a second rectangular sheet of material on the inner surface of the first sheet and seaming the two sheets together around the sides of the second sheet to form a first sealed chamber between the first and second sheets; seaming the top and bottom sides of the first sheet together to form a tube; partially everting the tube such that the left and right sides of the first sheet are adjacent one another and the outer surface of the first sheet forms the outer surface of the partially everted tube; sealing the left and right sides of the first sheet together to form a second sealed chamber; and providing first and second valves in the first sheet for inflation of the first and second chambers respectively; wherein the height of the second sheet is the same as or slightly less than that of the first sheet and the width of the second sheet is such that if the first chamber is fully inflated prior to inflation of the second chamber, the inflated volumes of the two chambers is roughly equal.
2. A method as claimed in Claim 1, wherein the width of the second sheet is between 25% and 50% of the width of the first sheet.
3. A method as claimed in Claim I, wherein the width of the second sheet is between 30% and 40% of the width of the first sheet.
4. A method as claimed in Claim 1, wherein the width of the second sheet is about 3 5% of the width of the first sheet.
5. A method as claimed in any preceding claim, wherein the material of the sheets is plastic and the seams are effected by welding.
6. A method as claimed in any preceding claim, wherein the valves are distinguished by an indicator adapted to identify which connects to the chamber which is to be inflated first.
7. A method of forming an inflatable arm-band substantially as described herein with reference to the accompanying drawings.
8. An inflatable arm-band made by the method of any preceding claim.
9. An arm-band comprising first and second separate air chambers each extending around a wearer's arm in use and having a common watt, wherein the potential inflated volume of the first chamber is roughly half that of the second chamber but wherein the construction of the arm-band is such that if the first chamber is fully inflated prior to inflation of the second chamber, the inflated volumes of the two chambers will be roughly equal.
10. An arm-band substantially as described herein, with reference to the accompanying drawings.