THIS INVENTION relates to shoulder straps, with replaceable cushioned inserts for golf bags, rucksacks and any other carry bags.
Shoulder straps are used as a convenient way of carrying heavy bags. Golf bags normally have one shoulder strap but sometimes have two. Rucksacks and baby carriers, for instance, are usually fitted with two shoulder straps.
Shoulder straps however often become uncomfortable after a time, especially when carrying a heavy weight.
DE-U-195 05 091 discloses a bag in which air sacks are provided in the straps or are arrached thereto.
According to the present invention, there is provided, a shoulder strap for bags, having means for receiving an insert, the insert comprising a sealed inflated air sack of supple non-porous material, and an opening in the strap to enable replacement of the air sack.
The insert can be made using walls made of a single layer of material or two or more layers. The thickness of material and the number of layers used will affect the resistance to accidental puncture of the insert.
The insert may be made of one complete tube or it could be constructed with sections. These sections could be totally separate and sealed off from one another. If one section is accidentally punctured the other sections would remain inflated. Alternatively the insert could have sections which are not totally separate form each other (if a gap is left between each section). This would allow the air to pass between the sections when the insert is under pressure i.e. when the shoulder strap is in use. This method could make the insert more malleable and able to spread the load throughout its length and width.
A specific embodiment of the invention will now be described by way of example, with reference to the accompanying drawing, in which:-
Two sheets of polyurethane are welded together using a high frequency welding tool with a "tear" seal on the outside.
As shown in Fig. 1 of the drawing, the insert is formed first leaving a small gap 1 in the outside seam. At the same time seams 2 are welded along the length and width which would allow the insert not to form a 'sausage' shape when inflated and also to have a 'hinged effect' which would fit comfortably over the shoulder. Gaps 3 are left between the inner and outer seams in order to allow the air to pass between sections when inflated.
Air is blown into the insert between the middle layers via the small gap 1 and this gap is then sealed off with another weld as shown in Fig. 2,4.
As shown in Fig. 4, the outer cover 5 of the shoulder strap has an opening 6 on its underside at one end to allow the insert to be placed in position. This opening can be sealed by means of "VELCRO", "poppers", zip, button or could be left open as a flap. Being on the underside of the strap the opening would have a tendency to remain closed.
The purpose of an opening in the shoulder strap is that should the insert be accidentally punctured, a replacement could easily be fitted.
Another specific embodiment of the invention is made as above but including a one-way valve 7 through which the insert would be inflated.
A further specific embodiment of the invention is made as previously described but using polyurethane tubing instead of sheets. This means that there is, in this instance, no need for a complete outside welded seam.