COOLING SYSTEM FOR BODY PROTECTION

The present invention is in the field of personal armour worn by individuals as protection against projectiles, bullets and the like. More specifically the present invention deals with measures for cooling the body of the wearer covered by such protective armour.

Excessive heat produced by the human body is dissipated by perspiration. The evaporation of the perspiration takes up heat from the body, thus producing a cooling effect. Personal armour typically blocks the flow of air around the body such that in hot conditions perspiration cannot be utilized efficiently to cool the body. The wearing of personal armour promotes the build - up of excessive heat at and around the surface area of the wearer. This observation is evident but stressed if the wearer is engaged in physical activity such as walking, running or working. Under hot environmental conditions the build - up of heat may be quick and permanent. The excessive build - up of heat at the body surface causes inconvenience to the wearer of the armour and in extreme cases of build up of heat, the physiological make up of the body can be damaged. It is therefore highly advantageous for wearers of personal armour to be able to relieve themselves of heat stress, to enhance their physiological functioning and protect against damage in extreme cases of build-up of heat.

US 5,970,519 and US 4,914,752 both disclose garments having a cavity into which air is introduced from an air supply. The cavity is defined between an impermeable outer layer and internal perforated layer so that the air introduced into the envelope is discharged through the inner layer to cool the wearer.

US 2001/0 000 849 A describes a garment forming a starting point for independent claim 1.

According to the present invention, there is provided a garment comprising an outer armour layer and a system for providing streaming air to evaporate perspiration from a wearer of said garment, said system comprising:

• an air blower or pump; and
• at least one enveloped voluminous layer having an enveloping shell which is substantially air impermeable and is perforated in the direction of said wearer, to permit the air introduced into the envelope by said air blower or pump to escape towards the body of the wearer, said at least one enveloped voluminous layer further having volume providing elements within it selected from the group consisting of foam elements, fibers and three dimensional net to keep the enveloped voluminous layer from collapsing or kinking.

• Fig. 1 is a cross sectional isometric view of a set of layers of the invention lying beneath the armour layer;
• Fig. 2 is a cross sectional isometric view of a layer set of the invention;
• Fig. 3 is a schematic isometric view of the enveloped layer of the invention indicating air flow through the system;
• Fig. 4 is a schematic armoured outfit showing the a folded - up corner displaying the layered structure.

In accordance with the present invention, a set of voluminous layers is disposed between the wearer of personal armour and his/her garments or body. The set is described schematically with reference to Fig. 1. Layer 20 represents the armour layer which is drawn for the sake of simplicity as a unitary layer but in reality may possess a compound structure. Layer 22 is the outermost layer of the set of the invention and layer 24 is the body contact layer, which juxtaposes the wearer's own garments or exposed body. Of the set of voluminous layers, layer 22 is enveloped by an impervious shell as is described schematically with reference to Fig. 2 to which reference is now made. In a cross sectional view, layer 22 juxtaposes body contact layer 24. Shell 26 envelopes layer 22, however not as shown, the shell completely wraps the layer. In more particular reference to the issue of relationships between the personal dress of the wearer and the body armour, there is no significance as to which is worn beneath.

In Fig. 3 to which reference is now made, the enveloped layer is described schematically, such that its function can be easily explained. Layer 22 is shown with its side juxtaposing the body contact layer on top. An air blower or pump 34 takes up ambient air through air intake 36. A hose 38 connects the air pump 34 with the enveloped layer 22. Air is driven through hose 38 to be forced into enveloped layer 22. The air 40 taken by the air blower is pushed through hose 38 into enveloped layer 22 and out through perforations such as perforation 42. In some embodiment an air hose is not used, and the air blower is connected directly to the enveloped layer. Air is forced out through the perforations as indicated symbolically by arrow such as arrow 44. The air driven out of the perforations enters the body contact layer (not shown) which is a voluminous layer, allowing further spread of the air stream to bathe the body and collect perspiration. In some embodiments a body contact layer is not applied. In a typical embodiment of the invention, the air pump or blower is powered by one or a plurality of batteries. The batteries are either packed together with the air pump or placed in a different location, with an appropriate cable connecting between the batteries and the air pump. Conveniently, the batteries are rechargeable so as to allow long hours of use with occasional charge. The technical properties of the air blower must be such that the stream of air is strong enough to allow sufficient flow in and around the area of the wearer's body covered by the layers of the invention. Volume providing elements are used to keep the enveloped layer (22) from collapsing and forming kinks and cramps. Such elements may be foam elements, fibers, three dimensional net, mechanical spacers or any other volume forming element.

A personal armour outfit implementing the system of the invention is descried schematically in Fig. 4 to which reference is now made. Outfit 50 is shown with a bottom corner folded up such that the layers are exposed. The external, armour layer 54 is at the top, external to the other layers. Beneath, layer 56 is the layer in which the air is forced initially, expelled from the air pump. Innermost is layer 58. In this drawing the air pump and hose are not shown.