Air Cooling Device for Protective Clothing and System Thereof

BACKGROUND OF THE INVENTION

Field of the Invention. This invention relates to a personal device preferably worn by a wearer of protective clothing, for reducing heat stress on the wearer of protective clothing, by cooling air and distributing that cooled air to desired areas of the body. In a preferred embodiment, the personal device is worn between the wearer of the protective clothing and the protective clothing, cooling the air between the wearer's body and the shell of the protective clothing.

Description of Related Art Published PCT patent applications WO 2015/151368-A1 and WO 2017/018532-A1 to Kawahara disclose a portable air circulation device that can be worn by an operator that is mounted on the inside of the clothes worn by the operator and applies cooled air to the human body of the worker. The device cools warm air by exchanging heat with a phase change material. Unfortunately, this design provides sufficiently cooled air (delta of greater than 10° C.) for a very limited time, generally less than 30 minutes. This can pose a difficultly in that the worker may have to stop work and be decontaminated in order to gain access to the device to restore the desired cooling functionality.

What is needed is a device that can cool the air in the space between body and garment for much longer times. Specifically, it is desirable to have a device that can reduce the temperature of the air in the space between the body and garment by at least 10 degrees Celsius and continuously provide that air for preferably at least 2 hours to address any heat stress issue associated with chemical protective clothing.

BRIEF SUMMARY OF THE INVENTION

- a) a sealable volume for the placement of phase change material for cooling the air, and
- b) a channel through the sealable volume that forms an air passageway that is in fluid communication with at least one of the one or more fan(s),
  - wherein the channel further comprises:
  - i) a plurality of interior fins extending from an inner channel wall into the air passageway, and
  - ii) a plurality of exterior fins extending from an outer channel wall into the sealable volume;
- wherein heat can transfer from air in the air passageway to any phase change material in the sealable volume.

This invention also relates to a cooling system for the wearer of the protective garment comprising a device for cooling the air between the protective garment and wearer, the device further having conduits for conveying cooled air to one or more desired areas of the wearer, wherein the device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air and one of more fan(s) for advancing the air through the heat transfer modules and further advancing and distributing that cooled air to the wearer via the conduits, and wherein the device further comprises an encasement for supporting and holding the plurality of heat transfer modules in a desired position, the encasement including an opening for accessing the plurality of heat transfer modules, the encasement further having one or more openings for the conduits.

This invention also relates to a protective apparel system for cooling a wearer of a protective garment, the system comprising the protective garment and a cooling system, the cooling system comprising a device for cooling the air between the protective garment and wearer, the device further having conduits for conveying cooled air to one or more desired areas of the wearer, wherein the device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air and one of more fan(s) for advancing the air through the heat transfer modules and further advancing and distributing that cooled air to the wearer via the conduits, and wherein the device also comprises an encasement for supporting and holding the plurality of heat transfer modules in a desired position, the encasement including an opening for accessing the plurality of heat transfer modules, the encasement further having one or more openings for the conduits; and wherein the device further comprises equipment for wearing the device by the wearer, the equipment supporting the encasement between the garment and the wearer of the garment; and the protective garment having a sealable opening for accessing the opening of the device encasement for the insertion and removal of heat transfer modules while the device is being worn.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of an embodiment of a device for cooling air between a garment and wearer of the garment, the device having a cooling unit comprising a plurality of heat transfer modules for cooling the air and two fans for advancing the air through the heat transfer modules. The figure includes one general version of an encasement for supporting and holding the plurality of heat transfer modules in a desired position; the encasement is shown with the cover opened.

FIG. 2 is an illustration of an expanded view of an embodiment of a heat transfer module comprising a sealable volume for the placement of phase change material for cooling the air.

FIG. 3 is an illustration of one embodiment wherein two half-modules that are mirror images of each other are combined with each other to form an enclosed channel through the sealable volume for an air passageway, with each half-module providing half of the channel.

FIG. 4 illustrates the reservoir for the phase change material in a half-module having a plurality of exterior fins extending from an outer channel wall into the sealable volume.

FIG. 5 is an illustration of one embodiment of a fully-assembled heat transfer module formed by attaching two half-modules to each other, the two half-modules having a shape that forms an enclosed channel through the sealable volume, with each half-module providing half of the channel.

FIG. 6 illustrates one method of adding a liquid phase change material to the reservoir of a half of a heat transfer module.

FIG. 7 is an illustration of one possible arrangement of a plurality of heat transfer modules arranged in parallel in the cooling unit with the channels of the heat transfer modules forming separate air passageways, with each air passageway in fluid communication with at least one fan.

FIG. 8 is an illustration of one possible arrangement of a plurality of heat transfer modules arranged in a series in the cooling unit with the channels of the heat transfer modules forming an air passageway that is in fluid communication with at least one fan.

FIG. 9 is an illustration of one possible arrangement of a plurality of heat transfer modules when the cooling unit has two or more series of heat transfer modules, with the series arranged parallel to each other, with the channels of each of the two or more series of heat transfer modules forming separate air passageways and each air passageway in fluid communication with at least one fan.

FIG. 10 is an illustration of one embodiment of a half-module having two separated U-shaped half channels with a plurality of internal fins, the two channels being mirror images of each other.

FIG. 11 illustrates the reservoir for the phase change material in a half-module having two separated U-shaped half channels that are mirror images of each other. The channels have a plurality of exterior fins extending from each outer channel wall into the sealable volume.

FIG. 12 illustrates the reservoir for the phase change material in a half-module having two separated U-shaped half channels that are mirror images of each other, further having a sealing top that closes the reservoir and creates a sealable volume.

FIGS. 14 & 15 illustrate one method of adding a liquid phase change material to the reservoir of a half of a heat transfer module having two separated U-shaped half channels that are mirror images of each other; and then sealing the reservoir by attaching a sealing top that closes the reservoir.

FIG. 16 is an illustration of one embodiment wherein two half-modules having two separated U-shaped half channels that are mirror images of each other are combined with each other to form two separate enclosed channels through the sealable volume for two separate air passageways, with each half-module providing half of each of the channels.

FIG. 17 is an illustration of one embodiment of a fully-assembled a heat transfer module formed by attaching two half-modules, having two separated U-shaped half channels that are mirror images of each other, to each other; the two half-modules having a shape that forms two separate enclosed channels through the sealable volume, with each half-module providing half of each of the channels.

FIG. 18 is an illustration of an embodiment of a device for cooling air between a garment and wearer of the garment, the device having a cooling unit comprising a plurality of heat transfer modules for cooling the air, and at least one fan for advancing the air through the heat transfer modules. The figure includes the base of one version of an encasement for supporting and holding the plurality of heat transfer modules in a desired position; the outer encasement cover is detached from the base and not shown. Additionally, this figure illustrates the device prior to the horizontal insertion of the heat transfer modules into the side of the encasement base.

FIG. 19 is an illustration of an embodiment of a device for cooling air between a garment and wearer of the garment comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air, and at least one fan for advancing the air through the heat transfer modules. The figure includes the base of one version of an encasement for supporting and holding the plurality of heat transfer modules in a desired position; the encasement outer cover is detached from the base and not shown. Additionally, this figure illustrates the heat transfer modules are now installed in the encasement base.

FIG. 20 is an illustration of an embodiment of a device for cooling air between a garment and wearer of the garment comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air, and at least one fan for advancing the air through the heat transfer modules; the device being contained inside one version of an encasement for supporting and holding the plurality of heat transfer modules in a desired position. In this view, the encasement is closed with the outer encasement cover shown attached to the base.

FIGS. 21 & 22 are illustrations of the worker prior to the donning of a protective garment. wearing a version of a closed encasement including a device for cooling air between a garment and wearer of the garment. The encasement is shown being worn on the worker's back over the worker's work clothes. Also shown is the portal in the outer encasement cover that allows the heat transfer modules to be removed and replaced without removal or opening of the encasement.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to a device for cooling air between a garment and wearer of the garment, wherein the device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air, and one or more fan(s) for advancing the air through the heat transfer modules. The heat transfer modules can be further provided with a phase change material (PCM) that provides cooling for the device. Preferably, the device uses and cools the air between the wearer of the garment and the garment shell, and preferably the device is worn between the wearer of the garment and the garment shell. The device preferably cools the air in the space around the human body inside the garment shell and circulates the cool air within the garment shell to keep the body comfortable while wearing the garment. In addition to the improved device design discussed herein, the cooling performance can be further maximized by controlling the fan speed mechanically or electrically as the ambient temperature changes.

The device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air, and one or more fan(s) for advancing the air through the heat transfer modules. Each heat transfer module comprises a sealable volume for the placement of phase change material for cooling the air, and a channel through the sealable volume that forms an air passageway that is in fluid communication with at least one of the one or more fan(s). The channel further comprises a plurality of interior fins extending from an inner channel wall into the air passageway, and a plurality of exterior fins extending from an outer channel wall into the sealable volume; wherein heat can transfer from air in the air passageway to any phase change material in the sealable volume.

Heat is absorbed or released when a material changes from solid to liquid and vice versa or when the internal structure of the material changes; phase change materials (PCM) are accordingly referred to as latent heat storage (LHS) materials. The PCM cools primarily by energy absorbed by the phase transition from solid to liquid because the latent heat or heat of fusion (melting) is generally much higher than the sensible heat. In cooling, the PCM melts at the phase change temperature (PCT), the PCM storing large amounts of energy in the PCM.

To cool warm air using a PCM, typically heat from the warm air must be transferred to a heat conducting material, which in turn transfers the heat to the PCM. The inventors have found that the key to extending the length of cooling was to better manage the heat conducting material/PCM interface. They found the PCM in direct contact with the heat conducting material melts first, forming a liquid boundary layer between the PCM and the heat conducting material. This liquid boundary layer forms a temperature gradient between the heat conducting material and the PCM, and as the liquid layer grows, the gradient increases to the point that even though there is still adequate PCM that is still solid and theoretically available for cooling, the liquid layer hinders the heat transfer from the heat conducting material to the PCM, resulting in shorter useful PCM life.

In the present heat transfer module, the heat conducting material preferably includes (a) the material of the channel through the sealable volume that forms an air passageway, (b) the material of the plurality of interior fins extending from an inner channel wall into the air passageway, and (c) the material of the plurality of exterior fins extending from an outer channel wall into the sealable volume that can contain or house the PCM.

The heat conducting material of the channel and the interior and exterior fins is preferably metallic, with aluminum, steel, copper, or combinations of these materials being representative. In some embodiments the preferred heat conducting material is aluminum, as it provides a balance between heat conductivity and cost. While some non-metallic materials have the potential to have more corrosion resistance, it is believed they are not suitable for the heat conducting material of the channel and the interior and exterior fins due to their generally much lower heat conductivity.

The inventors believe that the plurality of exterior fins extending from an outer channel wall into the sealable volume play a major role in extending the cooling life of the device. These exterior fins provide the heat conducting material additional surface area in contact with the PCM; these fins extend into the bulk of the PCM and help eliminate large expanses of PCM in the sealable volume so that the PCM is more efficiently used. In some embodiments, the surface area of the exterior fins, which transfer heat to the PCM, is preferably equal to or greater than the surface area of the interior fins, which transfer heat from the air, and in some preferred embodiments the surface area of the exterior fins is greater than the surface area of the interior fins.

The general shape, size, and number of the interior and exterior fins present need to balance surface area for heat exchange versus resistance to air flow. The interior fins preferably assist in breaking up laminar air flow on the interior surface of the channel, and in some preferred embodiments, interior fins have the shape of individual round pins extending from the interior channel surface or wall. In some embodiments, each channel has at least ten individual interior fins.

The exterior fins extend from the exterior channel surface or wall into the sealable volume for contact with the PCM, and their shape, size, and number are chosen to provide high surface area for contact with the PCM for heat transfer. In some preferred embodiments, these fins have a flat rectangular shape so they can extend into the far reaches of the length, width, and thickness of the sealable volume. If desired, some or all of the interior fins that extend into the interior of the channel, can be directly connected to the exterior fins that extend from the exterior of the channel, with some combination of round pin, rectangular, or combination of the two possible. In some embodiments, the channel has a combination of a plurality of round metallic pins extending through the channel wall, the round pins acting as both interior and exterior fins, with the channel having a plurality of additional rectangular metallic fins extending from the exterior of the channel into the sealable volume for contact with the PCM. In some embodiments, each channel has at least ten individual exterior fins.

It should be understood extending the cooling life of the PCM in the device is not simply a problem of how to provide more cooling, but a problem of more efficiently using the heat sink that the PCM provides to extend the life of the heat transfer modules in the cooling device.

FIG. 1 is an illustration of one embodiment of a device 10 for cooling air between a garment and wearer of the garment, the device comprising a cooling unit comprising a plurality of heat transfer modules 11 for cooling the air, and two fans 12. Also shown is an encasement 14 for supporting and holding the plurality of heat transfer modules in a desired position.

FIG. 2 is an illustration of one embodiment of an expanded heat transfer module 20 comprising a sealable volume 21 for the placement of phase change material for cooling the air. As shown in this embodiment, for ease of manufacture, the heat transfer module 20 comprises two half-modules 23 that are mirror-images of each other. Each half-module 23 has a separate sealable volume 21 created by closing a reservoir 24 with a sealing top 25.

As shown in FIG. 3, when the two half-modules 23 that are mirror images of each other are attached to each other, a channel 22 through the sealable volume is formed, with each half-module providing half of the channel. As shown, the preferred shape of the channel is a curved shape roughly in the form of a general “U” or sinusoidal shape that transits back and forth across the module to increase residence time in the module. Other shaped channels are believed useable, although entirely straight channels that run straight through the module in a straight line are generally thought to be undesirable as they typically provide less residence time in the module. The curved channels, particularly curved channels including fins, provide a complex structure that extends the air traveling time through the module and help provide sufficient time for heat exchange. Additionally, curved channels arranged in the modules as shown in the figures allow condensate from any moisture that might condense in the channels to flow downward by gravity, where it can be collected if desired in a reservoir at the bottom of the encasement. The channel 22 further comprises a plurality of interior fins 26 extending from an inner channel wall into the air passageway. In the embodiment shown in FIG. 3, the interior fins extend from one wall in the channel, a feature that simplifies milling the half module from an aluminum block. Also as shown in FIG. 3, preferably the fins are individual round pins centered in the channel, but other types of fins are possible.

FIG. 4 illustrates the reservoir 24 for the PCM in a half-module 23 having a plurality of exterior fins 27 extending from an outer channel wall into the sealable volume. As shown, preferably the fins are round pins, round pins with rectangular projections, rectangular projections, or some combination of these; attached and extending from the outer channel wall into the reservoir. Also shown is an optional fill port 46 for filling the reservoir with a PCM.

FIG. 5 is an illustration of one embodiment of a fully-assembled a heat transfer module 11 formed by attaching two half-modules to each other, the two half-modules 23 having a shape that forms an enclosed channel through the sealable volumes of the heat transfer module, the two sealable volumes formed by the two reservoirs with their associated sealing tops, with each half-module providing half of the channel.

As shown in FIGS. 4 & 5, the depth 42 of the channel into the half-module is preferably about one-half the thickness 44 of the half-module, meaning the channel has an overall depth 55 that is about the same as half the thickness of the total module. Preferably the exterior fins 27 extend from an outer channel wall into each reservoir, especially into the one-half of each reservoir thickness that does not contain any part of the exterior channel wall, and preferably each exterior fin extends into that reservoir thickness to the surface of the sealing top of the reservoir, leaving at most a small gap between the outer edge of the exterior fin and the sealing top. It is believed such a gap, if present, can preferably be about 10 percent or less of the distance between the interior surface of the sealing top when sealed on the reservoir and the surface of the exterior wall of the channel. Additionally, the exterior fins 27 extend into the reservoir between the external channel walls. In some embodiments, the external fins are configured such that the PCM can move throughout the reservoir without restriction; that is, the fins do not form any enclosed internal pockets in the reservoir that might hamper filling the entirety of the reservoir with PCM or form some localized region that could detract from the cooling performance.

FIG. 6 illustrates one method of adding a liquid phase change material 61 to the reservoir 124 of the half-module 123. The term “phase change material” (PCM) is commonly used to describe materials that use phase changes (e.g., melting, freezing, etc.) to absorb or release relatively large amounts of latent heat at a relatively constant temperature. The most commonly used PCM is water/ice, wherein water is added to the reservoir as shown in FIG. 6 and the reservoir is sealed; and then either the half-module or the fully assembled module is cooled to freeze the water. The frozen module is then used in the cooling device. Other types of PCMs are possible, including aqueous salt solutions or salt hydrates, wherein the salt may be but is not limited to soluble halides, sulphates, nitrates or phosphates of group 1 or group 2 metals and mixtures thereof, aqueous solutions of ethylene glycol, propylene glycol and/or polyols; and organic PCMs such as compositions comprising paraffins, fatty acids and esters, sugar alcohols that may be petroleum-based or derived from renewable sources. The PCM composition my also comprise gelling agents to increase the viscosity of the composition in its liquid phase to reduce the risk of leakage, and/or other additives such as corrosion inhibitors, surfactants, and biocides.

The performance of the PCM is related to its phase change temperature (PCT). In some embodiments, the PCM has a PCT of from −10° C. to 0° C. In some embodiments, the PCM has a PCT of from −10° C. to −5° C. In some preferred embodiments, the PCM is an aqueous solution of approximately 10 weight percent potassium chloride in distilled water, which has a PCT in the range of −10° C. to −5° C.

The device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air, and one or more fan(s) for advancing the air through the heat transfer modules. The embodiment illustrated in FIG. 1 has a device 10 comprising a cooling unit comprising four heat transfer modules 11 that can contain a PCM for cooling the air, and two fans 12. In this particular arrangement, each fan advances air through two of the heat transfer modules. Each fan can be located on the inlet of the heat transfer modules or on the exit of the modules, but each fan preferably draws air through the heat transfer modules to cool the air, and then blows that cooled air to desired areas between the wearer of the garment and the garment shell.

In some embodiments, each fan for moving the air through the heat module(s) is a sirocco fan, which is a centrifugal fan with a forward curved blade, which can move a large volume of air. However, essentially any fan that is of sufficient size and performance to distribute the air as desired can be used. Preferably each fan is attached to or mounted on the encasement, in fluid communication with one or more channels in the heat transfer unit(s). As such, each fan, like the encasement, is preferably used as the device is worn inside a protective garment.

Advantageously, each fan runs on electric power, which is preferably supplied by a portable power source compatible with the voltage/amperage required by each fan. The portable power source can be a battery or other power cell. Preferably, the portable power source is a rechargeable battery, such as a lithium-ion type battery. Preferably the portable power source is attached to or mounted on the encasement and is fitted with any number of switches or controllers for operating either the portable power source or each fan. As such, the portable power source, like the encasement, is preferably used as the device is worn inside a protective garment.

Preferably, the portable power source attached to or mounted on the encasement in a manner that allows quick changeout of a used or discharged portable power source with a new or charged portable power source. The protective garment can further have a special access panel for the power source if desired.

Further, while an exterior power source does not seem to be desirable in many applications, as typically such an external power source requires the attachment of electrical wires which might limit mobility; if mobility is not an issue the device can be equipped with an external socket or port for the attachment of an external power source.

If desired, the various switches or controllers for operating either the portable power source or each fan can optimize the wearer's comfort. For example, the temperature of the cooled air is very low when the device is first started and then the temperature gradually increases as the device is used, providing lesser cooling with time. On the other hand, the wearer's heat stress rises with time. Therefore, in some embodiments, the device has a controller that automatically controls each fan speed to control the amount of air being advanced through the device. For example, the controller could automatically set each fan speed at a low level when the device is turned on, and then increase each fan speed at some preselected time, or in response to an air temperature measured by a sensor. The increases in fan speed can be stepwise or gradual, with the highest speeds at the end of the wearing cycle to provide the most cooling when the wearer's heat stress is the highest.

In some embodiments, one or more of the heat transfer modules is interchangeable with one or more other heat transfer modules. In one example, for the most flexibility, all the heat transfer modules can be interchangeable. In another example, one can have two or more different sets of heat transfer modules, or one module can have some additional feature that the other modules do not have, such as a condensate reservoir. As previously discussed herein, the shape and slope of the channel(s) in the heat transfer modules allow any condensed moisture in the channel(s) to flow downward by gravity to be collected in an optional condensate reservoir at the bottom of the encasement.

In some embodiments, the plurality of heat transfer modules is arranged in parallel in the cooling unit with the channels of the heat transfer modules forming separate air passageways, with each air passageway in fluid communication with at least one fan. FIG. 7 is an illustration of one possible arrangement of the heat transfer modules in this embodiment, showing one orientation of the air channels, assuming a vertical cut has been made through one of the heat transfer module halves through the channel(s), revealing the cross section. Additionally, no fins are shown as this figure is only to illustrate the parallel arrangement of heat transfer modules and possible orientations/arrangements of the curved channels.

The plurality of heat transfer modules is shown horizontally arranged side-by-side with first heat transfer module 71 on the left and second of heat transfer module 72 on the right. Each heat transfer module has a channel forming a continuous air passageway through each module. As shown, there is a first air passageway 73 through the first heat transfer module 71 and a second air passageway 74 through the second heat transfer module 72. This type of arrangement is illustrative of the meaning of the plurality of heat transfer modules being arranged in parallel in the cooling unit with the channels of the heat transfer modules forming separate air passageways. Parallel, in this instance, means there are at least two concurrent air passageways in the cooling device, however, the actual shape of the channels and/or air passageways can be different.

In some embodiments, the plurality of heat transfer modules is arranged in series in the cooling unit with the channels of the heat transfer modules forming an air passageway that is in fluid communication with at least one fan. FIG. 8 is an illustration of one possible arrangement of the heat transfer modules in this embodiment, showing one orientation of the air channels assuming a vertical cut has been made through one of the heat transfer module halves through the channel(s), revealing the cross section. Additionally, no fins are shown as this figure is only to illustrate the arrangement of heat transfer modules and possible orientations/arrangements of the curved channels.

The plurality of heat transfer modules is shown vertically arranged with one stacked on the other, with first heat transfer module 81 on the top and second of heat transfer module 82 on the bottom. Each heat transfer module has a channel forming a continuous air passageway through each module. As shown, there is an air passageway 83 through the second heat transfer module 82 that continues through the first heat transfer module 81. This type of arrangement is illustrative of the meaning of the plurality of heat transfer modules arranged in series in the cooling unit with the channels of the heat transfer modules forming an air passageway. Series, in this instance, means the same air passageway continues through multiple heat transfer modules in the cooling device, the entrance and exits of the channels in each heat transfer module aligned forming the continuous air passageway. As before, the actual shape of the channels and/or air passageways can be different in the different heat transfer modules.

In some embodiments, the cooling unit has two or more series of heat transfer modules, with the series arranged parallel to each other, with the channels of each of the two or more series of heat transfer modules forming separate air passageways, with each air passageway in fluid communication with at least one fan. FIG. 9 is an illustration of one possible arrangement of the heat transfer modules in this embodiment, showing one orientation of the air channels, again assuming a vertical cut has been made through one of the heat transfer module halves through the channel(s), revealing the cross section; and again, no fins are shown as this figure is only to illustrate the arrangement of heat transfer modules and possible orientations/arrangements of the curved channels.

The plurality of heat transfer modules is shown in FIG. 9 with two series of heat transfer modules horizontally arranged side-by-side with first series 91 of heat transfer modules on the left and second series 92 of heat transfer modules on the right. Each heat transfer module series has a channel forming a continuous air passageway through all the modules in the series. As shown, there is a first air passageway 93 through the first series 91 of heat transfer modules and a second air passageway 94 through the second series 92 of heat transfer modules. This type of arrangement is illustrative of the meaning of the plurality of heat transfer module series being arranged parallel to each other, with the channels of each of the two or more series of heat transfer modules forming separate air passageways. Parallel, in this instance, means there are at least two concurrent air passageways in the cooling device; however, the actual shape of the channels and/or air passageways can be different in any series or any of the heat transfer modules.

FIGS. 10 to 20 further illustrate preferred embodiments of a device comprising a cooling unit comprising a plurality of heat transfer modules. FIG. 10 is an illustration of one embodiment of a half-module 123 having two separated U-shaped half channels 122 with a plurality of internal fins 126 (in this instance round pins), the two half channels being mirror images of each other.

FIG. 11 illustrates the reservoir 124 for the phase change material in a half-module 123 having two separated U-shaped half channels that are mirror images of each other. The channels have a plurality of exterior fins 127 extending from each outer channel wall into the sealable volume 121.

FIG. 12 illustrates the reservoir for the phase change material in a half-module 123 having two separated U-shaped half channels that are mirror images of each other, further having a sealing top 125 that closes the reservoir 124 and creating a sealable volume.

FIG. 13 is an illustration of an expanded view of an embodiment of a heat transfer module having two separated U-shaped half channels comprising a sealable volume for the placement of phase change material for cooling the air. Also shown in both FIGS. 10 to 13 is optional fill port 146 for filling the reservoir with a PCM provided with closing cap 146a.

FIGS. 14 & 15 illustrate one method of adding a liquid phase change material 161 to the reservoir 124 of a half of a heat transfer module 123 having two separated U-shaped half channels that are mirror images of each other; and then sealing the reservoir by attaching a sealing top 125 that closes the reservoir.

FIG. 16 is an illustration of one embodiment wherein two half-modules 123, having two separated U-shaped half channels 122 that are mirror images of each other, are combined with each other to form two separate enclosed channels through the sealable volume for two separate air passageways, with each half-module providing half of each of the channels.

FIG. 17 is an illustration of one embodiment of a fully-assembled a heat transfer module 111 formed by attaching two half-modules 123, having two separated U-shaped half channels that are mirror images of each other, to each other; the two half-modules having a shape that forms two separate enclosed channels through the sealable volume, with each half-module preferably providing half of each of the channels.

FIGS. 18 & 19 are illustrations of an embodiment of a device for cooling air between a garment and wearer of the garment comprises a cooling unit comprising a plurality of heat transfer modules 111 for cooling the air, and at least one fan 181 for advancing the air through the heat transfer modules. The figure includes the base 182 of one version of an encasement for supporting and holding the plurality of heat transfer modules 111 in a desired position; the outer encasement cover is detached from the base and not shown. Additionally, this figure illustrates the horizontal insertion of the heat transfer modules 111 into a portal in the side of the encasement base 182; with FIG. 18 showing the heat transfer modules prior to insertion and FIG. 19 showing the installed heat transfer modules. Both FIGS. 18 & 19 further illustrate a device further having conduits for conveying cooled air to one or more desired areas of the wearer. In this embodiment, neck air exit conduit 185 provides cooling air to the head and neck area and opposing air exit underarm conduits 186 on either side of the device provide cooling air to the underarm and shoulder area. Not shown in these views is the air inlet to the device, which is located at the bottom of the base.

FIG. 20 is an illustration of an embodiment of a device for cooling air between a garment and wearer of the garment, the device having a cooling unit comprising a plurality of heat transfer modules for cooling the air, and at least one fan for advancing the air through the heat transfer modules; the device being contained inside one version of an encasement for supporting and holding the plurality of heat transfer modules in a desired position. In this view, the encasement is closed with the outer encasement cover 200 shown attached to the base 182. In this embodiment, the cover snaps on the base by the use of tabs/holes 189 in the two parts, and the cover further has openings for the air exit conduits, the battery compartment portal, and the air inlet (not shown). If desired, the encasement can include various doors or latching mechanisms to retain the modules inside when the device is in use. Likewise, the encasement can be insulated to isolate the device from both the environment and the wearer of the device.

FIGS. 7 & 9 illustrate single-channel modules arranged with the air inlets and outlets arranged far apart on the left and right sides of the device, so two fans, or one fan with a manifold, would be needed to advance air through both channels. If desired, these individual modules can be arranged or flipped to bring the channel inlets and outlets together in the middle so they can more easily be potentially operated with a single fan, similar to the dual-channel module embodiment illustrated in FIG. 10 through FIG. 17.

The device comprising a cooling unit comprising a plurality of heat transfer modules for cooling the air, and one or more fan(s) for advancing the air through the heat transfer modules, can cool the temperature of the air supplied from the space between the body and garment by at least 10 degrees Celsius and can continuously provide that cooled air for preferably at least 2 hours to address any heat stress issue associated with chemical protective clothing.

Additionally, the device containing any of these arrangements of heat transfer modules can further comprise a condensate reservoir or a plurality of condensate reservoirs for collecting moisture that condenses in the channel. While this is not shown in the figures, the condensate reservoir or a plurality of condensate reservoirs are preferably positioned in the device at or near the bottom of the device, in liquid fluid communication with the channel or plurality of channels present in the device, so that any moisture that condenses in a channel during the cooling of the air is simply drawn downward by gravity into the condensate reservoir for emptying at a later time. Additionally, the condensate reservoir can comprise a material to capture the condensate, like a sponge or sponge-like material, and when the device is in use, this sponge or sponge-like material can be either removed and replaced with a dry version, or wrung out and replaced, to remove the captured condensate.

In some embodiments, the device further comprises equipment for wearing the device by the wearer of the garment. Such equipment can be any type of vest, harness, support strap(s) or other structure that can support the device on the person wearing the garment; both while the device is operating to supply cooled air to the worker, and while the device is not operating, typically before and after use.

FIGS. 21 & 22 are illustrations of the worker prior to the donning of a protective garment. wearing a version of a closed encasement 210 including a device for cooling air between a garment and wearer of the garment. The encasement is shown being worn on the worker's back over the worker's work clothes like a backpack. Also shown is the portal in the outer encasement cover that allows the heat transfer modules to be easily removed and replaced without removal or opening of the encasement by simply sliding the used heat transfer modules out of the closed encasement as shown in FIG. 22 and replacing them with fresh heat transfer modules.

In the broadest sense, the equipment for wearing the device could allow for wearing the device over the garment, as long as the device (and the garment) was supplied with inlet and outlet passages for obtaining air from inside the garment, transferring that air to the cooling device outside the garment worn by the wearer where it is cooled, and then re-supplying that air back into the garment. However, placing the device outside the garment risks contaminating the device unless other actions to cover the device are taken.

Preferably, the equipment for wearing the device allows positioning the device between the garment and the wearer of the garment, and in some embodiments the equipment for wearing the device positions the device on the back of the wearer.

In some preferred embodiments, the device further comprises conduits for conveying air either to or from the device; the conduits being in fluid communication with the one or more air passageways and the one or more fan(s) in the device. For example, there can be air input conduits that, using at least one fan in the device to forward the air, take air from one area between the garment shell and the wearer and advance that air to the heat transfer modules where the air is cooled, and the at least one fan can simply blow the cooled air from the device via one or more exit vents in the device. In a more practical example, the at least one fan pulls air from between the garment shell and the wearer in the area around the device via one or more inlet vent in the device, and advances that air to and through the heat transfer modules where the air is cooled; and the cooled air is then conveyed via one or more conduits to desired areas of the wearer's body. A combination of these examples is also possible, such as using one or more inlet conduits to take inlet air from the lower parts of the body, cooling the air, and then distributing the air to the upper parts of the body using one or more outlet conduits. In some embodiments, the conduits are configured to convey cooled air to the armpits and neck of the wearer, although other arrangements of conduits are possible.

As shown in FIGS. 6 & 14, or by use of the optional filling port, in one embodiment, the device allows the user to decide and use the PCM of his/her choice. For example, the user can add that PCM to the open reservoir followed by sealing or closing the reservoir to retain the PCM, or by injecting the desired PCM into a sealed/closed reservoir via the optional filling port. Alternatively, the device can further comprise a phase change material in the sealable volume of the heat transfer module; that is, the heat transfer module can be provided with a PCM already loaded into the reservoir, and optionally in some preferred embodiments the reservoir or sealable volume is permanently sealed or closed at the factory after the addition of the PCM, which can avoid both the need to add the PCM to the heat transfer modules and also reduce or prevent any potential leakage of the PCM from the heat transfer module.

In some embodiments, this invention relates to a cooling system for the wearer of the protective garment, the cooling system comprising a device for cooling the air between the protective garment and wearer, the device further having conduits for conveying cooled air to one or more desired areas of the wearer. The device comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air and one of more fan(s) for advancing the air through the heat transfer modules and further advancing and distributing that cooled air to the wearer via the conduits. The device further comprises an encasement as shown for example in FIGS. 1 & 20, for supporting and holding the plurality of heat transfer modules in a desired position, the encasement including an opening for accessing the plurality of heat transfer modules, the encasement further having one or more openings for attachment of the conduits. The opening for accessing the plurality of heat transfer modules can be made closable if desired.

In some embodiments, the cooling system can further comprise equipment that positions the encasement of the device on the back of the wearer as previously described herein. In some embodiments, the cooling system can further comprise one or more condensate reservoir(s) for collecting moisture generated by the cooling unit, as previously described herein.

In some specific embodiments, the cooling system comprises an encasement that supports and holds two heat transfer modules, and the conduits are configured to convey cooled air from the cooling unit to the armpits and neck of the wearer.

In some embodiments, this invention relates to a protective apparel system for cooling a wearer of a protective garment, the protective apparel system comprising the protective garment and a cooling system. The cooling system comprises a device for cooling the air between the protective garment and wearer; the device further having conduits for conveying cooled air to one or more desired areas of the wearer. The device also comprises a cooling unit comprising a plurality of heat transfer modules for cooling the air and one or more fan(s) for advancing the air through the heat transfer modules, and further advancing and distributing that cooled air to the wearer via the conduits. The device also comprises an encasement for supporting and holding the plurality of heat transfer modules in a desired position, the encasement including an opening (an optionally closable opening) for accessing the plurality of heat transfer modules. The encasement additionally has one or more openings for attachment of the conduits. The device further comprises equipment for wearing the device by the wearer, the equipment supporting the encasement between the garment and the wearer of the garment. The protective garment additionally has a sealable opening for accessing the opening of the device encasement for the insertion and removal of heat transfer modules while the device is being worn.

In some preferred embodiments, the device in the protective apparel system further comprises a condensate reservoir for collecting moisture generated by the cooling unit as previously described herein.

In some preferred embodiments, the equipment for wearing the device in the protective apparel system positions the encasement on the back of the wearer, and the sealable opening of the protective garment is on the back of the garment. In some preferred embodiments, the encasement of the cooling system supports and holds two heat transfer modules, and the conduits are configured to convey cooled air to the armpits and neck of the wearer.

The sealable opening of the protective garment is on the back or side of the garment and preferably includes an access panel of protective apparel fabric that can be pulled away from the garment for accessing the encasement while the garment is being worn. Once the access panel is opened the encasement can be opened so that one or more used heat transfer modules can be replaced to rejuvenate cooling without the wearer having to remove or unfasten the entire protective garment. Preferably this sealable opening can be provided with a slide fastener or a hook and loop fastener that can be opened to allow the access panel to be pulled away from the garment. The sealable opening can have various other features or arrangements as desired. For example, the sealable opening can have an internal liner that separates the encasement from the body of the wearer or otherwise provides additional exposure protection to the wearer when the access panel is opened. Such an internal liner would additionally need to have inlet and outlet access ports for air vents or conduits to allow air in the suit to be advanced to the encasement and then returned to between the garment shell and the wearer.

In some embodiments, the protective garment is an encapsulating chemical-resistant suit. In some embodiments the protective garment includes any type of coveralls with or without a hood. In some embodiments, the protective garment includes any type of shirt or coat or pants or combination garment.

The protective garment further preferably comprises protective apparel fabric. From a compositional standpoint, the term “protective apparel fabric” is meant to include a wide variety of protective garment fabrics, barrier fabrics, laminates, and films. The term “protective apparel fabric” also includes nonwoven and/or woven and/or knit fabrics and laminates of such materials with films or multilayer films. In some preferred embodiments the protective apparel fabric, and therefore the garment material, is a multilayer-film-and-nonwoven laminate.

In some embodiments the garment material is a nonwoven that resists penetration by liquids and/or particulates, such as a nonwoven like Tyvek® spunbonded polyethylene. Other useful protective apparel fabrics protect against a wide variety of threats and include but are not limited to those disclosed in U.S. Pat. No. 5,626,947 (Hauer et al.); U.S. Pat. No. 4,855,178 (Langley); U.S. Pat. No. 4,272,851 (Goldstein); U.S. Pat. No. 4,772,510 (McClure); U.S. Pat. No. 5,035,941 (Blackburn); U.S. Pat. No. 4,214,321 (Nuwayser); U.S. Pat. No. 4,920,575 (Bartasis); U.S. Pat. No. 5,162,148 (Boye); U.S. Pat. No. 4,833,010 (Langley).

Some specific protective apparel fabrics include those made from flash-spun polyethylene sheets that are spun and then lightly bonded, followed by a softening treatment; or with no subsequent softening treatment. One method of providing such flash-spun sheets is described in U.S. Pat. No. 5,972,147 to Janis. Another method of providing a sheet, the loosely consolidated flash-spun polyethylene sheet is point-bonded by passing the sheet between one or more heated rolls with raised bosses and a resilient roll, as described in U.S. Pat. No. 3,478,141 to Dempsey et al. Where a softer flash-spun sheet is desired, either sheet may be softened by passing the sheet through a pin or peg softening device such as disclosed U.S. Pat. Nos. 3,811,979 and 3,920,874 to Dempsey et al. Either sheet can be further coated with various compositions or laminated to film to create treated, coated or film-laminated products.

Other protective apparel fabrics include spunbonded nonwovens, melt-blown sheets and spunbonded combinations of melt-spun and melt-blown layers (e.g., SMS), electro-blown sheets and any combination thereof. The term “nonwoven” means the planar sheet structure comprises at least one web of randomly distributed fibrous material as opposed to woven or knitted fabrics that are made by interwoven yarns or interlocked yarn loops. In some preferred embodiments, the fibrous material in the nonwoven sheet is a synthetic polymer; in some embodiments the synthetic polymer is a thermoplastic polymer. In some preferred embodiments the fibrous material in the nonwoven sheet structure is free of added binder; that is, the fibrous material is bound in the sheet by melting of fibrous cross points in the sheet structure without additional binder compounds being added to the sheet. By fibrous, it is meant the material in the nonwoven sheet has some fibrous nature. This fibrous nature can be provided by such things as staple fibers, continuous or semi-continuous fibers, and/or plexifilamentary fibrous structures. The fibrous material can comprise a single material or a multitude of materials, either as a combination of different fibers or as a combination of similar fibers each comprised of different materials.

In some embodiments the fibrous nonwoven sheet structure prior to any additional treatment, coating, or film lamination, can have a basis weight of 75 grams per square meter or less. In some more preferred embodiments, the fibrous nonwoven sheet structure or the protective apparel fabric has a basis weight of 55 grams per square meter or less; and in some most preferred embodiments the fibrous nonwoven sheet structure or the protective apparel fabric has a basis weight of 45 grams per square meter or less. In some embodiments, the fibrous nonwoven structure or protective apparel fabric has a basis weight of 125 gram per square meters or less. In some embodiments the fibrous nonwoven structure or protective apparel fabric has a basis weight of 70 gram per square meters or less.

In some embodiments the garment comprising the protective apparel fabric is a Level A, B, C or D protective garment. Level A garments are used in situations that require the highest level of skin, respiratory, and eye protection, and are generally totally encapsulating vapor protective garments. Level B garments are used in situations that require the highest level of respiratory protection, but a lesser level of skin protection is needed. Preferably, the device for cooling air is used with Level C or Level D garments. Level C garments are used in situations where atmospheric contaminants, liquid splashes, and other direct contact will not adversely affect or be absorbed by any exposed skin. Level D garments are used in situations where contamination is only a nuisance. There may be some instances where combinations of protective apparel rated for A, B, C, or D level may be used together.

Air Cooling Device for Protective Clothing and System Thereof

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