SEARLE, Matthew John (74 High Street, Bruton Somerset BA10 0AJ, GB)
| Claims 1. Heat regulating apparel formed from a flexible substrate comprising: a first surface in which is formed at least a part of a distribution manifold having at least one substantially fluid impermeable distribution channel; and a second surface opposite to the first surface, the opposite surface having formed therein at least a part of at least one cooling channel, the at least one cooling channel producing a trough in the second surface of the flexible substrate, the trough being surrounded by bridging material; and a through-hole coupling the at least one impermeable distribution channel to the at least one cooling channel, the through-hole providing a fluid communication path across the flexible substrate. 2. Heat regulating apparel according to claim 1, wherein the through-hole is recessed within the trough of the cooling channel. 3. Heat regulating apparel according to claim 1 or 2, further comprising a plurality of cooling channels forming a plurality of spatially discrete cooling circuits that, in use, are temporally separable from one another. 4. Heat regulating apparel according to claim 3, wherein at least some of the plurality of cooling circuits include a plurality of cooling channels and each cooling circuit is coupled through a through-hole to one distribution channel. 5. Heat regulating apparel according to claim 1, 2 or 3, including a plurality of through-holes to each cooling channel. 6. Heat regulating apparel according to any preceding claim, further comprising a plurality of distribution channels forming a plurality of spatially discrete distribution circuits that, in use, are temporally separable from one another. 7. Heat regulating apparel according to any preceding claim, further comprising a sealing sheet applied across the first surface to seal and enclose the at least one -id- distribution channel, the sealing sheet preferably realizing an outer protective layer of a garment. 8. Heat regulating apparel according to any of claims 1 to 6, wherein the flexible substrate is formed of: a first sheet having a surface containing cut-outs formed therein that define at least some portion of one or more distribution channels; and a second sheet having an internal surface abutting against and coupled to the first sheet, thereby defining and sealing the at least one distribution channel therebetween, the second sheet further including an outer face in which is formed at least one cooling channel. 9. Heat regulating apparel according to claim 8, wherein the internal surface of the second sheet includes at least one cut-out that partially defines said distribution channel. 10. Heat regulating apparel formed from a flexible substrate comprising: first sheet and second sheets each having a substantially S-shaped profile, the first and second sheets coupled together to form a plurality of fluid impermeable cavities that realise at least one distribution channel, the at least one distribution channel each including a through-hole to an outside surface of one of the first and second sheets, the outside surface having formed therein a plurality of cooling channels that are in fluid communication with the at least one distribution channel via the through-hole. 11. Heat regulating apparel according to claim 1, wherein the through-hole is recessed within the trough of the cooling channel. 12. Heat regulating apparel according to any preceding claim, further comprising: an inner skin layer covering the second surface. 13. Heat regulating apparel according to any preceding claim, further comprising: a plurality of outwardly projecting ribs or pads (108) formed on the first surface of the substrate. 14. A cooling jacket comprising the heat regulating apparel of any preceding claim. 15. The cooling jacket of claim 14, further including an integrated compartment formed in an external surface of the jacket, the compartment arranged to hold, in use, a ventilation unit for the jacket, the compartment including an inlet port to the distribution manifold. 16. The cooling jacket of claim 14, wherein the inlet port includes a plurality of separate inlet holes. 17. A personal ventilation system containing: the heat regulating apparel of any of claims 1 to 13; and at least one of an air heater coupled to the distribution manifold; and a chilled air blower coupled to the distribution manifold. 18. Body armour incorporating the heat regulating apparel of any of claims 1 to 13, the jacket of claims 14 to 16 or the personal ventilation system of claim 17. 19. A method of fabricating heat regulating apparel, comprising the steps of: molding a flexible substrate such that it contains: a first surface in which is formed at least a part of a distribution manifold having at least one substantially fluid impermeable distribution channel; and a second surface opposite to the first surface, the opposite surface having formed therein at least a part of at least one cooling channel, the at least one cooling channel producing a trough in the second surface of the flexible substrate, the trough being surrounded by bridging material; and a through-hole coupling the at least one impermeable distribution channel to the at least one cooling channel, the through-hole providing a fluid communication path across the flexible substrate. |
Background to the Invention The present invention relates, in general, to a personal ventilation system and heat regulating apparel and is particularly, but not exclusively, applicable to a jacket or vest that is worn to cool its wearer.
Summary of the Prior Art Excessive exposure to heat can result in hyperthermia which occurs when the body produces or absorbs more heat than it can dissipate. In this condition, the heat-regulating mechanisms of the body eventually become overwhelmed to the extent that body temperature climbs uncontrollably; this is a medical emergency that requires immediate medical attention. A person who is wearing a protective garment, such a vest incorporating body armour, may have a higher risk of hyperthermia since protective garments are often heavy, have low moisture permeability (which prevents evaporation of sweat) and are multilayered whereby insulting air is trapped between the various layers.
In particularly hostile climatic conditions, such as in the desert, the combination of intense summer heat, body heat generated by having to wear a heavy ballistic vest and/or relative humidity imposes a significant physiological burden on troops wearing such protective body armour. In fact, body armour can block air circulation around the chest and back to an extent where up to 60% of the natural body cooling process is eliminated. Heat stress is therefore detrimental to operational efficiency of the troop since it can accelerate fatigue and can impair judgement.
A known armoured vest incorporating cooling is the Breeze™ active air circulated vest. This cooling vest, as disclosed in WO 2005/118167, is of multi-layer construction and includes an outer cover overlaying a ballistic panel. A sealed layer sits behind the ballistic panel and an air renovation space is realised by a breathable layer that lies behind the sealed layer. Finally, a flat spacing mesh provides an interior contact surface that sits closest to the wearer's body, the flat spacing mesh supposedly capable of allowing air within the air renovation space to cool the wearer. To assist with air circulation, a cooling fan blows air into the waist-region of the vest. Specifically, the cooling fan has an outlet that is enclosed between the sealed layer and the breathable layer, whereby a continuous flow of air is provided up the front and back of the vest to try to evaporate sweat. However, in this system, the air quickly becomes saturated with sweat so sweat is only evaporated from the area around the air entry point and the cooling capability is thus limited.
The Body Ventilation System (BVS) is a second form of personal cooling vest or "air distribution garment". The BVS was developed by Global Secure Safety Corporation and its structure is disclosed in WO2007005391. Particularly, the air distribution garment includes first and second spaced apart layers of a flexible, but strong, material that contour to a person's body, while also defining a plenum for the air to flow throughout the air distribution garment. A flexible cuff along a bottom seam of the air distribution garment allows coupling of a battery-powered blower and prevents air within the plenum from escaping from the bottom, thereby forcing the air upward and laterally within the plenum. An air dam is centrally positioned within the air distribution garment for directing the airflow from the blower in at least two different directions to facilitate propagation of the air throughout the air distribution garment. A spacer material is located within the plenum to prevent collapse of the spaced apart layers. Air holes are oriented along the outer seam or edge of the air distribution garment to allow air from the plenum to escape and carry heat away from the body. The placement of the air holes is near or along the outer seam of the garment or around the upper or side edges of the garment, although the air holes can be positioned anywhere on the outer fabric layer. Particularly, in understanding that air pressure is limited within the plenum, WO2007005391 locates the air holes close to the wearer's body to maximise air flow onto their body and supposedly to optimise a cooling effect induced thereby. A view of the performance of the BVS can be found in the European Journal of Applied Physiology 2008, vol. 103, no.3, pages 307 to 314. The blower may also act to as a filter for ambient air and it runs on standard rechargeable lithium-ion batteries with a typical operational life of up to about eight hours for each full charge. The BVS can be worn by a soldier as part of their personal gear and is compatible with the MOLLE vest, with the blower positioned in one of a number of alternative positions. However, the BVS system weighs about 2.5 kg (which is not inconsiderable). Also, the BVS system contains many individual elements which contribute to an increase in manufacturing costs.
US 5564124 relates to another air-ventilated cooling jacket or vest including a blower, the vest generally formed as a unitary garment that is worm over the upper torso of the wearer. A bladder is formed between two air impervious layers, e.g. fabric layers coated in polyethylene or the like. Portions of the garment are also formed of an air permeable material, such as foam, rubber or plastic that permits air flow to pass therethrough to provide specific areas of cooling to the wearer. More particularly, pads of porous material are formed at or near the seams or edges of the vest and especially at areas in the vest where sweating generally occurs. These pads are in fluid communication with the bladder (that is filled with air by a blower that is located at the base of the vest and generally towards its back). Air in the bladder is therefore allowed to escape through the pads. The nature and position of the porous pads means that this vest can be moderately easily damaged, especially in harsh physical environments. Also, the general environmental exposure of the porous pads means that these can become clogged with dirt and/or sweat.
Another garment-based technique for keeping the body cool makes use of a coolant liquid, such as chilled water, which is pumped through tubes which are attached to the garment to chill the garment. Such systems are typically closed systems in which the coolant is circulated through a cooling unit to maintain the garment and coolant at a chilled temperature. Although the entire system may be self contained, a person wearing the chilled garment must be tethered at all times to the cooling unit. The tether, of course, restricts the mobility of the wearer of the garment. Cooling by means of a liquid increases the weight of the cooling garment and also the complexity and cost of the system. In addition, the cooling and tank units that are required for the liquid coolant may impede the movements of the wearer (or others) when the system is used in confined areas or when movement in the work area is necessary.
US2006144557 discloses a thermodynamically efficient garment for cooling and/or heating a human body. The thermodynamic efficiency is provided in part by targeting the heat exchange capabilities of the garment to specific areas and/or structures of the human body. The heat exchange garment includes heat exchange zones and one or more non-heat exchange zones, where the heat exchange zones are configured to correspond to one or more high density ("HD") tissue areas of the human body when the garment is worn. A system including the garment can be used to exchange heat with the adjacent HD tissue areas under the control of a feedback control system. Sensed physiological parameters received by the feedback control system can be used to adjust the characteristics of heat exchange fluid moving within the heat exchange garment. This is a full body suit and is of complex design, thereby leading to high manufacturing costs.
Summary of the Invention
According to a first aspect of the present invention there is provided heat regulating apparel formed from a flexible substrate comprising: a first surface in which is formed at least a part of a distribution manifold having at least one substantially fluid impermeable distribution channel; and a second surface opposite to the first surface, the opposite surface having formed therein at least a part of at least one cooling channel, the at least one cooling channel producing a trough in the second surface of the flexible substrate, the trough being surrounded by bridging material; and a through-hole coupling the at least one impermeable distribution channel to the at least one cooling channel, the through-hole providing a fluid communication path across the flexible substrate.
In another aspect of the present invention there is provided a heat regulating apparelformed from a flexible substrate comprising: first sheet and second sheets each having a substantially S-shaped profile, the first and second sheets coupled together to form a plurality of fluid impermeable cavities that realise at least one distribution channel, the at least one distribution channel each including a through-hole to an outside surface of one of the first and second sheets, the outside surface having formed therein a plurality of cooling channels that are in fluid communication with the at least one distribution channel via the through-hole.
The heat regulating apparel may take the form of a cooling jacket or otherwise be integrated into or layered beneath body armour.
In another aspect of the present invention there is provided a personal ventilation system containing: the heat regulating apparel of the first or second aspect of the invention (as described in relation to claim 1 and 10); and at least one of an air heater coupled to the distribution manifold; and a chilled air blower coupled to the distribution manifold.
In a further aspect of the present invention there is provided a method of fabricating the heat regulating apparel, the method, comprising the steps of: molding a flexible substrate such that it contains: a first surface in which is formed at least a part of a distribution manifold having at least one substantially fluid impermeable distribution channel; and a second surface opposite to the first surface, the opposite surface having formed therein at least a part of at least one cooling channel, the at least one cooling channel producing a trough in the second surface of the flexible substrate, the trough being surrounded by bridging material; and a through-hole coupling the at least one impermeable distribution channel to the at least one cooling channel, the through-hole providing a fluid communication path across the flexible substrate.
The invention relates especially to a personal heat regulating apparel that may, in addition to circulating ambient air to selected parts of the body for evaporative cooling, be adapted to modify the ambient air for a specific operating environment to provide, for example, cooled, heated and/or filtered air to selected parts of the body.
In essence, the present invention describes a principle of producing a flexible core for a heat regulating apparel, such as a cooling jacket, that includes a distribution channel architecture on one side and a cooling channel architecture on the other side, the distribution channels and cooling channels interconnected by a fluid conduit. Preferably, the fluid conduit is located into a recess of the cooling channel and is thus spaced away from the wearer.
Advantageously, a preferred embodiment of the present invention provides a low-cost, low part-count, portable, lightweight and comfortable ventilation system that helps reduce heat-related injuries and heat stress, thereby improving the overall operational performance or efficiency of the wearer. Beneficially, the simplicity of construction and the flexible nature of the materials used to produce the distribution manifold of the substrate yield a personal cooling system that allows the wearer to move freely without impinging on any dexterity. Furthermore, the self-contained nature of the system means that, save for a manifold interface for the blower, the ventilation system is without tethers or restrictive ties.
Brief Description of the Drawings Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 is a representation of a prior art cooling vest having a multi-layer construction;
FIG. 2 is a front face view of a substrate of a personal heat regulating system of a preferred embodiment of the present invention;
FIG. 3 is a rear face view of the substrate of a personal heat regulating system of a preferred embodiment of the present invention;
FIG. 4 is a perspective view of a preferred embodiment of a cooling jacket constructed with the substrate of FIGs. 2 and 3; FIG. 5 is a view of a integrated blower compartment in the preferred cooling jacket of FIG. 4;
FIG. 6 is a cross-section through a preferred embodiment of a substrate material that may be used in the cooling jacket of FIG. 4;
FIG. 7 is cross-section through an alternate embodiment for a substrate material that may be used in the cooling jacket of FIG. 4; and
FIG. 8 is cross-section through another embodiment for a substrate material that may be used in the cooling jacket of FIG. 4. Detailed Description of a Preferred Embodiment
Referring briefly to FIG. 1, there is shown a representation of a prior art cooling vest 10 having a multi-layer construction. Particularly, the cooling vest 10 shows the so-called Breeze™ active air circulated vest. This cooling vest 10 has an outer cover 12 overlaying a ballistic panel 14. A sealed layer 16 sits behind the ballistic panel 14 and an air renovation space is realised by a breathable layer 18 that lies behind the sealed layer and a flat spacing mesh 20. The flat spacing mesh 20 also provides an interior contact surface
22 that sits closest to the wearer's body. To assist with air circulation, a fan 24 blows air into the waist-region of the vest, the fan 24 having an outlet that engages and seals into a socket 26 formed between the sealed layer 16 and the breathable layer 18.
Turning to FIGs. 2 and 3, a preferred embodiment a personal heat regulating system 40 is shown. The personal heat regulating system should be understood to relate, more generally, to a personal climate regulator whose form can be fashioned to resemble a jacket or other cover and whose function is to provide fluid flow to either cool or warm a body. The personal heat regulating system 40 of the preferred embodiment makes use of circulating air or gas to affect cooling.
The personal heat regulating system 40 includes a flexible substrate 42 that, on a first exterior surface 44, is configured in include a fluid distribution manifold 46 having a plurality of distribution channels 48, 50 interconnected to an intake port 52. The location of the intake port 52 is generally not important, although it is preferably located to support either a balanced flow of fluid in the distribution manifold and/or to limit any connection length to a pump or blower (reference numeral 80 of FIG. 4).
Generally, the flexible substrate 42 is formed to permit the channels to extend across both a front section 54 and a back section 56 of a garment, although this configuration is a design option. In the preferred embodiment, the distribution channels 48, 50 also extend around one side region 58 of the garment. In the exemplary form of a vest, the substrate therefore includes complementary pairs of cut-outs (60, 62), (64, 66), (68, 70) that, when assembled, define a neck opening in the vest and sleeve/shoulder openings in the sides of the vest.
The distribution channels may have a variety of diameters, a variety of lengths and a variety of orientations/geometries, as will be understood. More specifically, the distribution channels 48, 50 extend into one or more regions of the garment that require cooling, thereby providing fluid conduits to identified regions in the exterior surface 44 of the substrate 42.
The substrate 42 is preferably formed by a molding process (or its functional equivalent, as will be readily understood) that forms the distribution channels 48, 50 into the exterior surface 44. The substrate is therefore preferably formed from a foam (and particularly a closed cell foam) or aerated polymer/synthetic resin, e.g. thermo-formed plastics or cured polyurethane or polyehtylene. Again, the nature of the substrate is deterministic of the material that is used, with the substrate needing to be flexible and light.
In contrast with accepted wisdom in positioning air holes proximate to the skin to increase the local heat regulating effect (such as disclosed in the aforedescribed WO2007005391), the embodiments of the present invention preferably space the air holes away from the body of the wearer by effectively recessing them within cooling channels.
Referring specifically to FIG. 3, the substrate 42 includes a second, interior surface 72. The interior surface 72 includes at least one, but generally a plurality, of cooling channels 74, 76. The cooling channels 74, 76 may be interconnected to one another, although they may be arranged into separate related groups that can be selected individually or in combination. In a similar fashion to the distribution channels 48, 50 (formed in the exterior surface), the cooling channels 74, 76 are formed in the interior surface of the substrate 42. In this way the interior surface 72 has an undulating surface profile made up of a region of troughs or gullies (that realise specific cooling channels) separated by lands or bridge material 78. The bridge material 78 acts as a spacer. The cooling channels 74, 76 may have a variety of diameters, a variety of lengths and a variety of orientations/geometries, as will be understood. Their function is to deliver (cooling) fluid to identified regions of the garment or apparel that require heat regulation.
The distribution channels 48, 50 are coupled to the cooling channels by through-holes 79 (only one of which is shown in FIG. 4). The through-holes 79 may be formed by piercing the materials with a bradawl (or the like), or otherwise in the primary manufacturing stage for the substrate 42 (as will be understood) or otherwise in a secondary step, e.g. using a laser. The through-holes 79 provide a coolant fluid path from the distributor (exterior) channel side to the cooling (interior) channel side. By making use of the bridge material 78 to space the base of the cooling channels 74, 76 away from a plane that includes an upper surface of the bridge material, cooling fluid will always be permitted to flow in the cooling channels 74, 76 and the cooling channels will not be easily blocked by contact.
The through-holes 79 may be located at the beginning of a cooling channel 74, 76 and be provided on the basis of one through-hole per cooling channel. Alternatively, micro- diffusion may be employed wherein a plurality of relatively small holes are located between a specific distribution channel 48, 50 and its corresponding cooling channel(s) 74, 76. Also, to produce a concentrated effect, through-holes 70 may be clustered together in a particular region or differently sized through-holes may be used along the length of each cooling channel or with different cooling channels in potentially different cooling circuits.
The cooling channels may vent to an ambient environment, thereby allowing cooling fluid (e.g. chilled air) to pass along the cooling channel (74, 76) to either vent along the length of the cooling channel or otherwise to vent at one or more exhaust sites. Venting can be directly onto the skin of the wearer, or otherwise through pores in a secondary permeable membrane located proximate to the skin of the wearer. In terms of the general surface finishes of the substrate 42, it is preferably that at least the exterior surface 44 is made of an impermeable material or coating to ensure that a maximum volume of coolant be delivered to the cooling channels 74, 76. The impermeable nature of the distributor channel may be produced during the molding process, an over- molding process, by coating with a close-fitting sheet or by impregnating the substrate's surface with a compound. For example, the coating may be a stretch air-impermeable fabric such as spandex, chloroprene, spun-bonded polyester or other similarly functioning material or fabric. In essence, the functional requirement to maximise delivery of cooling fluid is deterministic (as will be readily appreciated by the skilled addressee) and is arranged to cope with the delivery of pressurised air to the through-hole(s).
In summary, the substrate 42 is constructed to contain two sets of channels on opposing faces of the substrate, with the two sets of channels (i.e. the distribution channels 48, 50 and the cooling channels 74, 76) connected together by one or more through-holes 79. The bridging material 78 between the cooling channels 74, 76 also functions as a cushion and spacer.
Turning to FIG. 4, an assembled cooling jacket 100 constructed with the substrate 42 of FIGs. 2 and 3 is shown. In this instance, the substrate's exterior surface 44 is preferably covered with an outer protective layer 102 of material, e.g. a coloured fabric. As would be generally expected, the cooling jacket will include some form seam 103 to attach the outer protective layer 102 to (at least) the substrate 42. In relation to the interior surface 72, the preferred embodiment also includes an inner skin layer 104 that covers the interior surface to provide an acceptable, e.g. soft, smooth, hard-wearing and/or non sticky, skin-contact surface. Of course, alternative or complementary methods of joining the skin layer 104 and/or the protective layer 102 to the substrate are contemplated, including the use of adhesives, welding and stapling (to name by a known few).
In a particular embodiment, the exterior surface 44 of the substrate 42 may be formed to include additional (outwardly projecting) ribs or pads 108; these are entirely optional and act either in a decorative fashion or otherwise as separators that support and cushion the placement of, for example, body armour on top of the personal heat regulating system of the present invention.
Although the cooling jacket 100 is contemplated as being provided in a range of sizes in order to fit users of differing physical statures, the preferred embodiment is provided with shoulder adjustment straps 110 attached in the upper frontal area (i.e. chest). In addition, corresponding buckles (not shown) or similar devices are attached at the top of the shoulders. Manipulation of the shoulder straps 110 allows the jacket 100 to be further adjusted to fit the physique of the individual user. As other examples, Velcro ® strapping or webbing can be used for adjustment. The cooling jacket 100 is also provided with side strapping 112 to permit the cooling jacket to be secured in position around the waist of the wearer. Fastening can be accomplished in a number of ways, including hooks, ties, loop-fasteners, buckles and Velcro ® .
In relation to the blower (or pump) 80, a preferred embodiment sites the pump within a compartment 120 integrally formed (in plastic) in the substrate 42; this is shown in FIG. 5. The blower/pump 80 may be press fitted into the compartment, or otherwise secured with ties, such as Velcro ® straps 124.
In a preferred (but optional) embodiment, the blower/pump 80 can be constructed to provide intermittent coolant flow to specific distribution channels 48, 50 and their related cooling channels 74, 76. In this respect, reference is made to co-pending UK patent application No: 0808949.2 (filed on 16 May 2008), assigned to the present Applicant. More specifically, in relation to the blower compartment 120, the inlet port 52 into the distribution manifold may be realised by a plurality of separate inlet holes 130-138 (which may be of different sizes). The inlet holes 130-138 feed into specific distribution channels 48, 50 that are not interconnected. By using a blower 80 whose exhaust can be directed (e.g. by use of a rotating sleeve that selectively opens or blocks one or more of a plurality of exhaust orifices from the blower 80), the cooling jacket 100 of the preferred embodiment can be configured to have intermittent coolant flow to different areas of the jacket 100 (or other apparel). The intermittent coolant flow (e.g. filtered and chilled air) is therefore achieved by one or both of spatial and/or temporal control, thereby enhancing the physiological sensation to the wearer.
Air flow through the personal ventilation system can either be pressurized to the extent that there is a relatively high coolant velocity through the manifold and cooling channels (via a single through hole), or otherwise it can be in the form of a constant, relatively slow "leaky pipe" arrangement (where multiple holes are positioned along the length of the cooling channel).
The blower or air pump can be configured as a filter, if required.
With reference to FIG. 6, there is shown a cross-section through a preferred embodiment of a substrate 42 that may be used in the cooling jacket of FIG. 4. The substrate 42 includes an outer face 140 that includes at least one distribution channel 48 formed therein. The inner face 142 of the substrate includes (in this case) two cooling channels 144, 146 (of optionally varying geometry and depth), the two cooling channels 144, 146 in fluid communication with the distribution channel 48 through (in this case) through- holes 150, 152. The exemplary nature of FIG, 6 shows the through-holes 150, 152 to be of different diameters. Land or bridge material 78 separates the cooling channels 150, 152 which, in this case, are within a single cooling circuit (by virtue of the common distributor channel 48). The undulating and opposing faces of the substrate 42 are therefore separated from each other by cushioning material having a varying depth between I 1 and I 2 . The distribution channel 48 is closed to produce a substantially air- impermeable conduit by a protective (or sealing) layer 102, which protective layer 102 may be the final exterior layer of the cooling jacket 100. In terms of the interior surface/inner face 142, the skin layer 156 may optionally be applied over the undulating inner surface 142.
Having regard to FIG. 7, a cross-section through an alternate embodiment for a substrate 170 (that may be used in the cooling jacket of FIG. 4) is shown. In this case, the substrate is formed of two sheets that are joined along a split line 172 by a suitable coupling mechanism, e.g. an adhesive layer 174. A first sheet 176 has an internal surface 177 including cut-outs 178 that define at least some portion of one or more distribution channels 180-184. To produce a coolant impermeable distribution channel, a second sheet 186 includes an internal surface 188 including either an entirely flat surface or (preferably) cut-outs 190-194 that define at least some portion of the distribution channels 180-184. Appropriate alignment of the respective cut-out in the first sheet 176 with the second sheet 186 therefore defines (in this case) a plurality of distribution channels. Again, through-holes (in this case multiple through holes 200-203) connect the distribution channels 180-184 to cooling channels 206-210 formed in an outer face 212 of the second sheet 186, the outer face therefore having an undulating profile.
Another embodiment for a suitable substrate 220 is shown in FIG. 8. In this case, the substrate is formed of two sheets 222, 224 that both possess an undulating, repeating contiguous S-shaped or wave-shaped profile. The two sheets 222, 224 are joined together, such as through a weld 226 or the like, so that a generally cylindrical cavity 228 can be formed between the respective trough regions 230 and peak regions 232 of each sheet. The cylindrical cavity 228 acts as the distribution channel. Through-holes 234 are formed in one of the sheets, the through-holes 230 providing a fluid passageway from the cylindrical cavity 228 to (approximately) a mid-point in the S-shaped profile of one of the two sheets. In this way, a single mold can be used to manufacture a common S-shaped sheet, whereafter through-holes are formed in a second-stage process. Again, the lower sheet (supporting the cooling channels) provides a spacer.
Protective layers and protective skins (as describe in relation to FIG. 6) may be applied, if considered necessary by the skilled artisan in view of the materials selected for the substrate.
The manufacturing processes employed to produce the various embodiments of the substrate are readily known in the art. Furthermore, it will be understood that, molding need not be employed to produce both parts of the substrate's distribution and cooling channels, although this is preferred. It will, of course, be appreciated that the above description has been given by way of example only and that modifications in details may be made within the scope of the present invention. For example, while a preferred embodiment describes apparel that is suitable for use with body armour and in a hot operational environment, the present invention finds wider application to the general regulation of heat. Specifically, the present invention may make use of heated air to warm the wearer where circulating air is heated prior to being circulated within the substrate's fluid distribution manifold. Consequently, references to "cooling" should not be considered as limiting since the invention is more widely applicable to temperate conditioning. Moreover, while the preferred embodiment is deployed under (or integrated into) body armour, the substrate of the present invention may form the basis of an outer garment designed to be warn by, for example, a policeman on outside duty, whereby the wearer would otherwise be subjected to an ambient environment that could cause either sweating or shivering. Other application of the garment/apparel of the present invention include surgeons or staff working in operating rooms, since these professionals often wear protective clothing that both limits air circulation next to their bodies and which inhibits evaporative cooling. Likewise, technicians working in clean room environments or with toxic waste cleanup crews or the like wear may make use of the garment/apparel of the preferred embodiments of the present invention.
Equally, while the preferred embodiment references the use of the substrate fashioned into the form of a jacket or vest, it will of course be appreciated that the substrate can be made into any garment, including a blanket or over cover. In fact, the present invention can be used to regulate the body temperature of any human or animal.