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Title:
PORTABLE APPARATUS AND METHODS USING PHASE CHANGE MATERIALS FOR CREATING A TEMPERATURE STABILIZED ENVIRONMENT
Document Type and Number:
WIPO Patent Application WO/2017/147287
Kind Code:
A1
Abstract:
A carrying case utilizes a layer of phase change materials and a thermal insulation layer in order to provide a temperature-stabilized environment for enclosed payloads during transport through an environment in which temperatures differ greatly from those to which they are normally exposed. In one aspect, the phase change materials and thermal insulation provide an extended period of temperature constancy, without the addition of either active thermal control or excessively bulky insulation.

Inventors:
GOLDIE JAMES H (US)
MACOMBER STEPHEN (US)
Application Number:
PCT/US2017/019112
Publication Date:
August 31, 2017
Filing Date:
February 23, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
FRUITION LLC (US)
International Classes:
A45C13/02
Domestic Patent References:
WO2014067927A12014-05-08
Foreign References:
US20080164265A12008-07-10
US20120330388A12012-12-27
US20070032774A12007-02-08
US20030124318A12003-07-03
US20100264048A12010-10-21
US20080164265A12008-07-10
Other References:
"High-Tech Outdoors", POPULAR MECHANICS, vol. 167, no. 3, March 1990 (1990-03-01), pages 132, XP055413346, ISSN: 0032-4558, Retrieved from the Internet [retrieved on 20170413]
"Low emissivity", WIKIPEDIA, 27 December 2015 (2015-12-27), pages 2 - 3, XP055411833, Retrieved from the Internet [retrieved on 20170413]
ANDERBERG: "How to Wax Your Own Clothing and Gear", THE ART OF MANLINESS, 3 June 2014 (2014-06-03), pages 2, XP055411834, Retrieved from the Internet [retrieved on 20170413]
"Styrofoam", WIKIPEDIA, 20 December 2015 (2015-12-20), pages 1 - 3, XP055411855, Retrieved from the Internet [retrieved on 20170413]
See also references of EP 3419472A4
Attorney, Agent or Firm:
GORDON, David P. (US)
Download PDF:
Claims:
WHAT IS CLAIMED IS:

1. A portable carrying case, comprising: a first layer containing phase change material (PCM) with a phase change temperature between 50°F and 70°F; a second layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement.

2. A portable carrying case according to claim 1 , wherein said phase change temperature is between 60°F and 66°F.

3. A portable carrying case according to claim 1 , wherein said second layer comprises a fabric layer.

4. A portable carrying case according to claim 1 , wherein said second layer comprises a fibrous insulation layer.

5. A portable carrying case according to claim 1 , further comprising a low emissivity layer located between said first layer and said second layer.

6. A portable carrying case according to claim 5, further comprising :

a fabric layer provided over said second layer, said fabric layer being at least one of wear- resistant, water-resistant, and impermeable to water vapor.

7. A portable carrying case according to claim 1 , wherein said portable carrying case comprises six sides.

8. A portable carrying case according to claim 7, wherein said first and second layers are located in each of said six sides.

9. A portable carrying case according to claim 7, wherein said first layer comprises at least two removable inserts attached to two respective sides of said six sides by fasteners.

10. A portable carrying case according to claim 7, wherein said first layer comprises a layer having six sections defined by seams, said layer being foldable at said seams to define said enclosure, said portable carrying case further comprising fasteners that extend from a plurality of the sections to another section.

1 1. A portable carrying case according to claim 1 , wherein said portable carrying case comprises a front panel and a back panel that meet at three closed edges and define said opening to said enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, said front panel and said back panel each comprised of said first layer and second layer.

12. A portable carrying case according to claim 1 1 , wherein said flap is comprised of said first layer and said second layer.

13. A portable carrying case according to claim 1 1 , further comprising a low emissivity layer located between said first layer and said second layer.

14. A portable carrying case according to claim 1 1 further comprising a fabric layer provided over said second layer, wherein said fabric layer is at least one of wear-resistant, water-resistant, and

impermeable to water vapor.

15. A portable carrying case according to claim 1 1 , further comprising a fastener coupled to said flap and to one of said front panel and said back panel.

16. A portable carrying case according to claim 1 1 , further comprising a waterproof zipper or seal coupled to said front panel and said back panel and covered by said flap in its said second position, and said zipper or seal movable from a first position where said enclosure is open to a second position where said zipper or seal further seals said opening against passage of water vapor into or out of said enclosure.

17. A portable carrying case according to claim 1 , further comprising a temperature display having one side attached to said first layer and a second display side.

18. A portable carrying case according to claim 17 wherein said temperature display includes a first display that shows a shorter temperature range with relatively finer resolution and a second display that shows a wider temperature range with relatively coarser resolution.

19. A portable carrying case according to claim 17 wherein said PCM layer has a transparent flexible cover open to an exterior of said carrying case to permit visual and tactile observation of a state of said first layer.

20. A portable case according to claim 1 , wherein said carrying implement is at least one of a handle and a strap.

21. A portable case, comprising: a hard shell ; a cushioning layer; an insulating layer; a phase change material (PCM) layer with a phase change temperature between 50°F and 70°F; and a handle, wherein said hard shell, said insulating layer and said PCM layer define an enclosure with at least one closable opening.

22. A portable case according to claim 21 , wherein said insulating layer extends around said PCM layer, said hard shell extends around both said PCM layer and said insulating layer, and said handle extends from said hard shell.

23. A portable case, comprising: a front panel and a back panel that meet at three closed edges and define an opening to an enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, a fastener coupled to said flap and to one of said front panel and said back panel, wherein said front panel and back panel are each comprised of a first layer containing phase change material with a phase change temperature between 50°F and 70°F and a second layer comprising insulation.

24. A method of transporting a temperature-sensitive object, comprising : placing the object in a carrying case having a plurality of layers, including a layer having a phase change material (PCM) and an insulation layer; carrying the carrying case with the object from a first location at a first temperature where the PCM in the carrying case is in a first state, into a location or environment at a second temperature which causes the PCM in the carrying case to start changing state to a second state while stabilizing the temperature in the carrying case; bringing the carrying case with the object to a second location or environment having an ambient temperature near or at the first temperature; opening the carrying case and removing the object; and permitting the carrying case to at least partially recharge at said second location.

25. A portable carrying case for a musical instrument, comprising: a segmented, flexible first layer comprising phase change material (PCM) having a phase change temperature between 60°F and 66°F; a second layer comprising fibrous insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement comprising at least one of a handle and a strap.

26. A portable carrying case according to claim 25 wherein said portable carrying case comprises a front panel and a back panel that meet at three closed edges and define said opening to said enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, said front panel and said back panel each comprised of said first layer and second layer.

27. A portable carrying case, comprising: a front panel and a back panel comprised of insulation that meet at three closed edges and define an opening to an enclosure, a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, a fastener coupled to said flap and to one of said front panel and said back panel, and at least one multi-segmented flexible PCM insert that is insertable into and removable from said portable case.

28. A portable case according to claim 27, wherein said at least one multi-segmented flexible PCM insert has a fabric cover, is foldable, and includes at least one handle.

29. A portable carrying case, comprising: a first layer containing phase change material (PCM) with a phase change temperature between 80°F and 100°F; a second layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement.

30. A portable carrying case, comprising: a first layer containing phase change material (PCM), a first portion of said PCM having a phase change temperature between 50°F and 70°F and a second portion of said PCM having a phase change temperature between 80°F and 100°F; a second layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement.

AMENDED CLAIMS

received by the International Bureau on 05 July 2017 (05.07.2017)

1. A portable carrying case for carrying a payload, comprising:

a first, inner layer containing phase change material (PCM) with a phase change temperature between 50°F and 70°F;

a second, outer layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening and a space for carrying the payload, wherein said first layer is between said space and said second layer; and

a carrying implement.

2. A portable carrying case according to claim 1, wherein said phase change temperature is between 60°F and 66°F.

3. A portable carrying case according to claim 1, wherein said second layer comprises a fabric layer.

4. A portable carrying case according to claim 1, wherein said second layer comprises a fibrous insulation layer.

5. A portable carrying case according to claim 1, further comprising a low emissivity layer located between said first layer and said second layer.

6. A portable carrying case according to claim 5, further comprising:

a fabric layer provided over said second layer, said fabric layer being at least one of wear-resistant, water-resistant, and impermeable to water vapor.

7. A portable carrying case according to claim 1, wherein said portable carrying case comprises six sides.

8. A portable carrying case according to claim 7, wherein said first and second layers are located in each of said six sides.

9. A portable carrying case according to claim 7, wherein said first layer comprises at least two removable inserts attached to two respective sides of said six sides by fasteners.

10. A portable carrying case according to claim 7, wherein said first layer comprises a layer having six sections defined by seams, said layer being foldable at said seams to define said enclosure, said portable carrying case further comprising fasteners that extend from a plurality of the sections to another section.

11. A portable carrying case according to claim 1, wherein said portable carrying case comprises a front panel and a back panel that meet at three closed edges and define said opening to said enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, said front panel and said back panel each comprised of said first layer and second layer.

12. A portable carrying case according to claim 11, wherein said flap is comprised of said first layer and said second layer.

13. A portable carrying case according to claim 11, further comprising a low emissivity layer located between said first layer and said second layer.

14. A portable carrying case according to claim 11 further comprising a fabric layer provided over said second layer, wherein said fabric layer is at least one of wear-resistant, water- resistant, and impermeable to water vapor.

15. A portable carrying case according to claim 11, further comprising a fastener coupled to said flap and to one of said front panel and said back panel.

16. A portable carrying case according to claim 11, further comprising a waterproof zipper or seal coupled to said front panel and said back panel and covered by said flap in its said second position, and said zipper or seal movable from a first position where said enclosure is open to a second position where said zipper or seal further seals said opening against passage of water vapor into or out of said enclosure.

17. A portable carrying case according to claim 1, further comprising a temperature display having one side attached to said first layer and a second display side.

18. A portable carrying case according to claim 17 wherein said temperature display includes a first display that shows a shorter temperature range with relatively finer resolution and a second display that shows a wider temperature range with relatively coarser resolution.

19. A portable carrying case according to claim 17 wherein said PCM layer has a transparent flexible cover open to an exterior of said carrying case to permit visual and tactile observation of a state of said first layer.

20. A portable case according to claim 1, wherein said carrying implement is at least one of a handle and a strap.

21. A portable case for carrying a payload, comprising:

a hard shell;

a cushioning layer defining circular cutouts for at least partially surrounding said payload;

an insulating layer;

a phase change material (PCM) layer with a phase change temperature between 50°F and 70°F; and

a handle, wherein said hard shell, said insulating layer and said PCM layer define an enclosure with at least one closable opening.

22. A portable case according to claim 21, wherein said insulating layer extends around said PCM layer, said hard shell extends around both said PCM layer and said insulating layer, and said handle extends from said hard shell.

23. A portable case, comprising: a front panel and a back panel that meet at three closed edges and define an opening to an enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, a fastener coupled to said flap and to one of said front panel and said back panel, wherein said front panel and back panel are each comprised of a first layer containing phase change material with a phase change temperature between 50°F and 70°F and a second layer comprising insulation.

24. A method of transporting a temperature-sensitive object, comprising: placing the object in a carrying case having a plurality of layers, including a layer having a phase change material (PCM) and an insulation layer; carrying the carrying case with the object from a first location at a first temperature where the PCM in the carrying case is in a first state, into a location or environment at a second temperature which causes the PCM in the carrying case to start changing state to a second state while stabilizing the temperature in the carrying case; bringing the carrying case with the object to a second location or environment having an ambient temperature near or at the first temperature; opening the carrying case and removing the object; and permitting the carrying case to at least partially recharge at said second location.

25. A portable carrying case for a musical instrument, comprising: a segmented, flexible first layer comprising phase change material (PCM) having a phase change temperature between 60°F and 66°F; a second layer comprising fibrous insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement comprising at least one of a handle and a strap.

26. A portable carrying case according to claim 25 wherein said portable carrying case comprises a front panel and a back panel that meet at three closed edges and define said opening to said enclosure, and a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, said front panel and said back panel each comprised of said first layer and second layer.

27. A portable carrying case, comprising: a front panel and a back panel comprised of insulation that meet at three closed edges and define an opening to an enclosure, a flap coupled to one of said front panel and said back panel and movable from a first position where said enclosure is open to a second position where said flap covers said opening, a fastener coupled to said flap and to one of said front panel and said back panel, and at least one multi-segmented flexible PCM insert that is insertable into and removable from said portable case.

28. A portable case according to claim 27, wherein said at least one multi- segmented flexible PCM insert has a fabric cover, is foldable, and includes at least one handle.

29. A portable carrying case, comprising: a first layer containing phase change material (PCM) with a phase change temperature between 80°F and 100°F; a second layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement.

30. A portable carrying case, comprising: a first layer containing phase change material (PCM), a first portion of said PCM having a phase change temperature between 50°F and 70°F and a second portion of said PCM having a phase change temperature between 80°F and 100°F; a second layer comprising insulation, said first layer and second layer arranged to form an enclosure defining at least one closable opening; and a carrying implement.

Description:
PORTABLE APPARATUS AND METHODS USING PHASE CHANGE MATERIALS FOR CREATING A

TEMPERATURE STABILIZED ENVIRONMENT

BACKGROUND

1. Field

[0001] The present disclosure relates to portable apparatus having a temperature stabilized environment. More particularly, the present disclosure relates to carrying bags and containers for delicate and/or expensive devices which are ideally contained in a temperature stabilized environment to protect them from quick transitions from warm to cold environments or vice versa. The present disclosure has particular application to carrying bags and containers for musical instruments although it is not limited thereto.

2. State of the Art

[0002] The transport of temperature-sensitive equipment, instruments, devices or objects through extreme weather conditions can result in costly damage to these items. In particular, oboes, clarinets, bassoons, cellos, violins, guitars and other musical instruments made from wood have been observed to crack during or after exposure to cold temperatures. A common occurrence, for example, is for the top joint of an oboe to crack while being played, after it has been carried outdoors in its case on a cold winter day or evening. Cracking is an abrupt event that can render an instrument unplayable during a performance or rehearsal. Further, a time-consuming and costly repair is required, and in some instances the instrument or the affected portion of the instrument is unsalvageable.

[0003] It is believed that humidity as well as temperature plays a role in this phenomenon, but humidity and temperature are coupled, and, therefore, control of the temperature in the space in which an instrument is kept is primary and resistance to loss of water vapor from this space is secondary. Typically, musical instruments are placed in a hard case, which is then placed in a snugly fitting fabric case cover for transport (see Figure 1 ). A damp sponge may be placed in the hard case alongside the instrument to maintain some level of humidity within the hard case. Case covers provide a measure of thermal protection, as well as protection against shock and handling. However, wooden instruments continue to crack even when carried in these prior art cases and case covers after having been subjected to large temperature differentials.

SUMMARY

[0004] A carrying case utilizes a layer of phase change materials and a thermal insulation layer in order to provide a temperature-stabilized environment for enclosed payloads during transport through an environment in which temperatures differ greatly from those to which they are normally exposed. In one aspect, the phase change materials and thermal insulation provide an extended period of temperature constancy, without the addition of either active thermal control (i.e., batteries and heaters) or excessively bulky insulation. The result can be a compact, reliable carrying case that benefits a wide range of equipment, devices, and objects that are temperature sensitive or at risk of being damaged from exposure to abnormal temperatures.

[0005] In one embodiment, a carrying case comprises a "soft" outer carrying bag that fits around a hard inner case that is used for an object or device such as a musical instrument. The soft outer carrying bag includes a plurality of layers, including 1 ) an inner layer having a phase change material (PCM) contained in an optionally segmented flexible sheet comprising multiple pockets or cells, and 2) an outer insulation layer that may also serve as a shock absorber. The PCM is designed to change phase at a temperature of between 50°F and 70°F, and preferably between 55°F and 70°F, and more preferably at a temperature of between 60°F and 66°F. In one embodiment, a low emissivity layer is located between the phase change material layer and the outer insulation layer. In one embodiment, a wear-resistant and/or water-resistant fabric layer is provided over (outside) the outer insulation layer or may constitute the outer insulation layer itself. In one embodiment, the fabric layer is impermeable to water vapor.

[0006] In one embodiment the carrying case is designed as a pouch with three closed edges and a closable flap adjacent an opening into the pouch.

[0007] In one embodiment, the carrying case is provided with liquid crystal temperature indicators (LCTIs) that are coupled to the PCM layer. The LCTIs provide a visual indication of the temperature of the PCM layer.

[0008] A method of transporting a temperature-sensitive instrument, equipment, device or object (hereinafter broadly referred to as "object") includes placing the object in a relatively hard instrument case, and placing the hard instrument case in a relatively soft, temperature-stabilized, outer carrying case. The soft outer carrying case includes a plurality of layers, including an inner layer having a phase change material (PCM) contained in a segmented flexible sheet and an outer insulation layer that may also serve as a shock absorber. The PCM is designed to change phase at a temperature of between 50°F and 70°F, and preferably between 55°F and 70°F, and more preferably at a temperature of between 60°F and 66°F. In one embodiment, a low emissivity layer is located between the phase change material layer and the outer insulation layer. In one embodiment, a wear-resistant and/or water- resistant fabric layer is provided over (outside) the outer insulation layer or may constitute the outer insulation layer itself. The fabric layer may be impermeable to water vapor.

[0009] Additional aspects, embodiments, objects and advantages of the disclosed methods may be understood with reference to the following detailed description taken in conjunction with the provided drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Fig. 1 is a prior art schematic showing a hard instrument case contained in a case cover.

[0011] Fig. 2 is a temperature time plot for the interior of the case cover of Fig. 1. [0012] Figs. 3a-3d are diagrams of a carrying case utilizing a layer of phase change materials and a thermal insulation layer, with Figs. 3a and 3b showing the bag closed, Fig. 3c showing the bag opened with a hard instrument case contained therein and Fig. 3d showing the hard instrument case removed from the carrying case.

[0013] Fig. 4 is a transparent view diagram of the carrying case of Figs. 3a-3d.

[0014] Fig. 5 is a temperature versus time plot for the interior of the carrying case of Fig. 4 as modeled and as measured.

[0015] Fig. 6 is a plot showing the time over which phase change material freezes as a function of the outdoor temperature.

[0016] Figs. 7a and 7b are respectively a top view schematic of a segmented flexible phase change material layer and a side view schematic of an alternative segmented flexible phase change material layer.

[0017] Fig. 8 is a plot showing the factor by which the effective specific heat of encapsulated paraffin with disparate phase change temperatures spanning a range of temperatures exceeds the specific heat of water.

[0018] Fig. 9 is a cross-sectional diagram of another embodiment.

[0019] Figs. 10a and 10b are respectively a transparent view diagram, and an open-bag perspective view with one detachable PCM thermal insert in place and one removed of another embodiment.

[0020] Figs. 1 1 a and 1 1 b are respectively a diagram of a PCM thermal insert in an open configuration and in a folded configuration in another embodiment.

[0021] Fig. 12 is a perspective view diagram of another embodiment of a carrying case showing a pouch with three closed edges.

[0022] Figs. 12a and 12b are respectively a diagram of a pouch with a removable PCM insert and a cross-section through location A-A of the insert.

[0023] Fig. 13 is a measured temperature vs. time plot for the interior of the carrying case of Fig. 12.

DETAILED DESCRIPTION

[0024] Turning to Fig. 1 , a prior art schematic shows a hard case 1 1 contained in a case cover 13. The hard case may carry an object such as a musical instrument. The hard case and the musical instrument contained within, in combination, are assumed to possess a heat capacity C and to be isothermal at temperature T inb while the external environment is shown with a temperature T 0 . It is noted that the temperature at the interior of the case cover 13 is assumed to be equivalent to the hard case 1 1. Heat loss from the hard case 1 1 through the case cover 13 to the external environment is shown as Qi oss . [0025] As heat is lost to the outdoor environment through the thermal insulation of the case cover 13, the hard case and the instrument contained within it gradually cool. The rate at which the temperature at the interior of the case cover drops (dT int /df) is related to both the rate of heat loss (Q toS s) through the case cover and the heat capacity (C) of the hard case (including the instrument within it) according to

^int _ _ Qloss , .. > dt C

The rate of heat loss (Q /0S s) is related to the difference in the temperature at the interior of the case cover { Tim) and the temperature of the surrounding external environment ( T 0 ) :

Qloss = K ext (^int _ ^θ )' ( 2 ) where K ext is the thermal conductance from the interior of the case cover to the external environment. Substituting Eqn. (2) into Eqn. (1 ) yields

(3)

dt C

The solution of this differential equation is

Ά ϊ = Τ 0 + {τ ιΛ 1_ 0 0 ) εχρ (4) where T int | t=0 is the temperature at the interior of the case cover when it is first brought out into the cold. This is an exponential decay in the temperature difference between the interior of the case cover and the surrounding outdoor temperature. In one instance, T int is considered to be at room temperature ( T rt ) when the case cover is first ex osed to the cold, and, therefore:

This result is graphed conceptually in Figure 2, where it is seen that the temperature at the interior of the case cover (and of the hard case) exponentially approaches the temperature of the surrounding environment ( T 0 ). The temperature difference decays to 37% of its initial value after one time constant {t=C/K ext ). After two time constants, the temperature difference is only 14% of its initial value. It is noted that in Figs. 1 and 2, the model looks at the temperature of the interior of the case cover, which is assumed to be equal to the hard instrument case contained inside the case cover. The instrument case and instrument are treated as isothermal, since the temperature difference between the exterior of the instrument case and the instrument it holds will be small compared to the temperature difference between the instrument case and the external environment on a cold day or evening.

[0026] Turning to Figs. 3a-3d and 4, a carrying case 100 is shown that employs the ability of materials to naturally store and release heat. In particular, and as seen best in Fig. 4, the carrying case 100 utilizes an inner layer 1 10 of phase change material (PCM) that absorbs and releases a significant amount of energy (known as the "latent heat of fusion") as the PCM transitions from one state to another (e.g., from a liquid state to a solid state - also called "freezing") and an outer insulation layer 120 which may be made from a fiber insulation such as THINSULATE (a trademark of 3M Corporation). If desired, a low emissivity sheet of material 130 (seen in Fig. 4) such as the low emissivity foil TEMPTROL (a trademark of Temptrol Corp. of New Jersey) may be located between the PCM layer 1 10 and the insulation layer 120. Also, if desired, a wear-resistant, water-resistant fabric layer 140, such as

CORDURA (a trademark of Invista of Kansas) or Sur Last® (by Glen Raven of North Carolina) may be provided over (outside) the outer insulation layer 120. The fabric layer 140 may also be impermeable to water vapor. Alternatively, a separate water vapor-impermeable layer (not shown) may be provided. The carrying case 100 may be provided with a zipper or other closure means 150, and a handle 160 or shoulder strap (not shown) or both. The handle 160 may be a split handle with one loop attached to each portion of the cover 100a, 100b and may be made from webbing. The carrying case 100 is dimensioned to fit over a relatively hard case 170 as seen in Fig. 3c and optionally may provide spare space for commonly used instrument accessories. By way of example only, the hard case 170 may be a musical instrument case that includes a handle 172.

[0027] In one embodiment, the phase change material (PCM) is a material formed from salt hydrates, paraffins, or fatty acids which is contained in a segmented flexible laminate sheet as discussed hereinafter. In another embodiment, the PCM material is a segmented package sold under the name MATVESL PURETEMP by Entropy Solutions of Plymouth, Minnesota. As described earlier, during exposure to cold temperatures, heat is gradually lost to the environment through the carrying case insulation, and the interior of the carrying case cools. However, with the layer of PCM 1 10 present, once the interior of the carrying case cools to the temperature at which the PCM changes state

("freezes"), the PCM, initially in its liquid state, begins the phase change process. Frozen pieces of PCM gradually form and grow in number and extent, surrounded by PCM in its liquid state which remains at or slightly above the freezing temperature. Therefore, although there will be slight variations in temperature throughout the volume of PCM, the temperature of the two-phase solution of PCM comprised of solid and liquid PCM remains virtually constant at or very near the phase change temperature T pc , until the entire quantity of PCM is frozen. The time necessary to complete the phase change is large, due to 1 ) the large latent heat of fusion (i.e., energy released from phase change) of the PCM and 2) the high resistance (°C/W) to heat loss to the environment through the low emissivity layer 130, the insulation layer 120, and convection at the outer surface of the carrying case cover 100. Over the duration of this phase change process, the temperature descent of the musical instrument and hard case 1 1 , which is in close thermal contact with the PCM layer 1 10, is arrested at or near the temperature

Tpc-

[0028] In one embodiment, the PCM material is provided with a phase transition temperature selected to be between 50°F and 70°F. In another embodiment, the PCM material is provided with a phase transition temperature selected to be between 55°F and 70°F; and in another embodiment to be between 60°F and 66°F; e.g., 64°F. [0029] Where the temperature within the interior of the carrying case remains constant at the phase change temperature ( T pc ) while the PCM undergoes freezing, the length of time that the temperature at the interior of case cover holds constant at T pc is equivalent to the time it takes for the PCM to freeze, which can be estimated by:

where h fusion is the specific heat of fusion of the PCM, m pcm is the mass of the PCM, and T pc is the phase change temperature of the PCM. The basis for this expression is clear; the numerator is the heat (e.g., in Joules) released by the PCM to complete its phase change, and the denominator is the rate at which this heat escapes from the case cover to the surrounding air (J/s).

[0030] For purposes of illustration only, a prototype carrying case suitable for enclosing a double clarinet case has been constructed as seen in Figs. 3a-3d and Fig. 4. The approximate exterior dimensions of case 100 is seventeen inches width by thirteen inches height by 5.25 inches depth, which represents a total outer surface area of A = 0.49 m 2 (with suitable unit conversions). A commercially available synthetic fiber material (THINSULATE - a trademark of the 3M Company of Maplewood, Minnesota) was used for thermal insulation layer 120 with a thickness of £ in sui = 0.8 inches (0.020 m) and an effective thermal conductivity of approximately k = 0.044 W/m-K. The thermal conductance of the insulation of the case cover (K insu l) can then be estimated by

0.044 w / x 0.49 m 2

" -insul - n - A A - 1.1 / i - \ i )

^nsul 0 · 20 m / A

The effective conductance of the convective heat transfer ( κ ∞ην ) from the outer surface of the case cover to the surrounding air is estimated by

K conv = hA = 5 y m 2 K * 0.49 m 2 = 2.5 ¾ , (8) where a value of 5 W/m 2 K has been used for the convective heat transfer coefficient (as published by Engineers Edge LLC for a thirty degree C temperature difference). See,

hiip:/.\vww.engineersedge.com/heat transfer convective heat transfer coefficients 13378.htm. The net thermal conductance to the external environment (K ext ) of equations (2) to (6) is then computed by

K , K

insul conv 1 1 · 1 1 W // J ? 5 w //K

The PCM used was 390 g of commercially-available encapsulated paraffin with a specific heat of fusion of hf USIon = 150 J/g and T pc = 64 °F (= 18 °C). Equation (6) can be used to estimate the time over which freezing of the PCM occurs during exposure of the case cover to 30 °F (= -1.1 °C):

[0031] Figure 5 shows the temperature at the inside of the case cover versus time, as predicted by the thermal model of equation (5), assuming the values shown in Table 1 below, both without and with PCM present with T pc = 64 °F (18 °C). The addition of the PCM is modeled as simply a 67-minute delay in temperature descent, beginning at the instant that the temperature reaches the phase change temperature (64 °F). Also shown on the graph for the purpose of comparison are measured

temperatures versus time at the interior of the case cover (with PCM present). The measured temperatures show a stabilized temperature well above the temperature predicted by the model for a carrying case without PCM present.

Table 1. Values used in thermal model for predicted temperature vs. time curves of Fig. 5

[0032] The carrying case may, of course, be exposed to colder temperature than T 0 = 30 °F during winter transport. Fig. 6 shows the time of freezing for other assumed values of T 0 in equation (10). As expected, the time of freezing of the PCM decreases (and, hence, so does the duration of thermal protection) as the outdoor temperature decreases. For example, the freezing time as modeled dropped to only thirty-six minutes when the carrying case is exposed to an external temperature of 0 °F. The curve shown assumes the values given in Table 1 for T pc , h fusion , m pcm , and If, for example, the mass of PCM were doubled to 780 g, then the freezing time would double as well (see equation (6)).

[0033] In addition to delaying the temperature descent of the hard case contained within the carrying case, the carrying case may delay changes in humidity, both relative and absolute, at the interior of the carrying case and, hence, the hard case and musical instrument, by impeding the passage of water vapor molecules from the interior of the carrying case to the exterior environment. Accordingly, fabrics that are water resistant or even impermeable to water in both its liquid and vapor phases, as well as employment of closure methods that seal against moisture transport, may be used.

[0034] In one aspect, the phase change temperature of the PCM is selected to be below room temperature (i.e., T pc < T rt ) or else the PCM will not return to its liquid phase when it is brought indoors and will not provide the desired temperature stabilization due to phase change during subsequent exposure to the outdoors. In the above calculations, the PCM used was assumed to have a phase change temperature ( T pc ) of 64 °F (= 18 °C). This value is reasonable, since it maintains the interior of the case cover at a temperature safe for the enclosed case and instrument. However, T pc also determines the time needed for the PCM, which has fully or partially frozen during outdoor transport, to fully re-melt when the case cover comes indoors. In one embodiment the phase change temperature ( Tpc) is chosen to be far enough below room temperature that the PCM can regain its liquid state (i.e., melt) in the time available between trips outdoors.

[0035] The time needed to melt the PCM can be estimated from

. h jusion m , . . . tmelt = > H I )

where equation (1 1 ) is identical with equation (6), except that T rt - T pc has been substituted for T pc - T 0 and K int for K ext , where K int is the thermal conductance from the PCM to the room temperature air, when the case cover is indoors.

[0036] In one aspect, it is enlightening to divide equation (1 1 ) by equation (6):

The temperature-related factor on the right-hand side of equation (12) is larger than unity. For example, with the values assumed above of T pc = 18 °C, T 0 = -1.1 °C, and T rt = 21 °C, this factor is 6.4. Assuming Kext, = K int , this would mean that the melting of the PCM would take 6.4 times longer than the freezing did. In one aspect, it may be acceptable for the melting to take longer than the freezing, since the carrying case (and enclosed instrument and case) are typically inside rather than being transported outdoors. However, it one embodiment, it is desirable that t me i t /t freeze be small rather than large. More particularly, the condition that ensures that the PCM will continue to provide thermal protection is

where f, ns cie and are the times spent inside and outside, respectively, over any arbitrarily chosen interval of time of duration f me/f + t freeze .

[0037] Equation (1 1 ) indicates that it is could be desirable that the carrying case be designed to maximize K inb since this will shorten the time necessary for the PCM to melt during indoor exposure. Therefore, in one embodiment, the carrying case is designed such that, when zipped open, the interior of the carrying case is fully exposed to the room temperature air (once the instrument case is removed), as shown in Fig. 3d. With the carrying case left open, there is no insulation between the PCM 1 10 and the warm air in the room, and K int is considerably greater than K ext . Equation (9), the expression for K ext , can be used to estimate K int simply by setting κ ιηβ α =∞ (since no insulation is present on the interior of the carrying case) so that:

^nt = ^„v = 2.6 W / K (14) Plugging in the above numbers into equation (13) yields the following:

or, alternatively:

t ..ns..d,e > 1 9 = Q 66 (1 6)

^outside inside l ~ t ~ 1.9

[0038] For the specific example using the above numbers, equation (16) implies that in order to have uninterrupted temperature protection from the PCM for a carrying case assumed to be exposed to -1.1 °C (30 °F) while outdoors and 21 °C (70 °F) while indoors, the carrying case should be kept indoors for at least 66% of the time over any 194-minute period of time (= t mett + t freeze = 1.9 x 67 min. + 67 min.). This result depends, of course, on the values of T pc , T rt , T 0 , κ Μ , and K ext , so this value applies to only this set of values for these parameters. Further, although this specific example considers only two temperatures, it will be appreciated that the carrying case may be exposed to greater than two temperature over the course of its daily use.

[0039] In one aspect, it will be appreciated that of all the parameters impacting the temperature stability provided by the case cover, T pc and K ext are perhaps the most easily changed. In particular, T pc may be changed by selecting the desired PCM, while K ext may be changed by adjusting the amount of insulation present. Per equation (13), decreasing T pc reduces the fraction of time that the carrying case must be kept inside. Increasing the amount of fiber insulation decreases K ext (see equations (7) and (9)), which also decreases the fraction of time that the carrying case must be kept inside (see equation (13)).

[0040] The carrying case still provides some measure of thermal protection even if the PCM is entirely frozen, since the thermal insulation continues to operate independently of the PCM.

[0041] As seen in Figs. 3c and 3d, in one embodiment, the carrying case 100 can open like a book when unzipped, in order that the PCM at the interior of the carrying case is fully exposed to the warmth of the room in the manner described above.

[0042] In some embodiments, features are added to the carrying case to both ensure that the user does not neglect to leave the carrying case open when indoors and that the "footprint" is minimized. For example, a resilient element may be added that causes the carrying case to naturally open when it is unzipped. Alternatively, or in addition, the carrying cover can bend back on itself (i.e., be opened by 360 degrees), and if desired, a hook and loop (e.g., Velcro) fastener may be added to keep the case cover bent back on itself. In lieu of the Velcro, one of a myriad other apparatus, including snaps, clips, short zipper, etc. can be employed.

[0043] Additionally, it will be appreciated that actions may be taken by a user to fully recharge (fully melt) the PCMs within the carrying case before exposing the case and its enclosed objects to cold outdoor temperatures, in the event that the conditions implied by equations (15) and (16) are not met, due, for example, to 1 ) extended or frequent outdoor exposure, 2) insufficient time indoors, or 3) use of a PCM with a phase change temperature T pc greater than the temperature of the indoor environment in which the carrying bag is kept. By way of example only, such actions may include placement in a clothes dryer at a temperature safe for the carrying bag ; placement adjacent to and above a baseboard heater, radiator, or other heating device within the home; and placement of a hot water bottle or other heating element into the interior of the carrying case.

[0044] As previously mentioned with respect to Fig. 4, a low emissivity material 130 is optionally provided between PCM layer 1 10 and insulation layer 120 of the case cover. The low emissivity material 130 is intended to reduce heat flux through the case cover from radiation heat transfer, which represents another mode of heat loss to the environment. In one embodiment, the low emissivity material can be TEMPTROL, and it may be oriented with its shiny surface outward (i.e., toward the fiber insulation 120) per the manufacturer's recommendations.

[0045] In one embodiment, the PCM layer 1 10 is formed by encapsulating PCM in a spherical shell, and, therefore, the encapsulated PCM can be deployed in the carrying case, or any device for that matter, as if it were a solid material, although the PCM itself will transition between its solid and liquid phase during use. For example, PCM may come as beads or pellets with diameters of 4 to 5 mm from Microtek Laboratories in Dayton Ohio, or as powder with particles with diameters of 14 to 24 μιιη, also from Microtek Laboratories. The PCM beads or pellets may be placed in measured amounts in the cutouts of a flexible layer 1 1 1 having multiple cutouts, separated by intermediate members 1 12, as seen in Fig. 7a. After all the cutouts are filled, the flexible layer is covered with a flexible, top and bottom sheet, each of which is sewn, bonded, melted or sonically welded to the intermediate members to form a flexible PCM layer with multiple PCM-filled cutouts, thereby approximating an even distribution of PCM. Thus, in one embodiment, care is taken to ensure that the PCM remains distributed over the surface area of the case cover, rather than settling to the lowest point of the layer. In one embodiment, for ease of manufacture, multiple small fabric or plastic bags are pre-filled with a PCM beads or pellets and then placed side by side in each of the cutouts. The resulting multi-segment PCM layers are placed inside the insulation layer (with an optional low emissivity material therebetween) and are sewed in place, so that they cover the base, the top, both ends, and both large faces of the case cover. In another embodiment, the PCM material is encapsulated in a segmented bilaminate package such as a layer of MATVESL PURETEMP as previously described, resulting in regularly-spaced trapped volumes or pouches of PCM, as seen in Fig. 7b. The sections between the trapped volumes or pouches are thin, thereby providing flexibility of the segmented package, which may optionally be enclosed between a top and bottom fabric sheet. According to one aspect, the segmentation of the inner PCM layer maintains the intended distribution of phase change material (PCM) over the area of the layer despite the tendency to settle. In another aspect, segmentation provides suitable flexibility of the layer regardless of whether the PCM is in its liquid or solid phase. According to yet another aspect, segmentation minimizes the quantity of escaped PCM in the event of a breach of the PCM containment. [0046] In one embodiment, a PCM-based carrying case is used to keep payloads from getting too hot (rather than too cold) during transport or exposure to high temperatures. In this embodiment, the PCM material is chosen with a phase change temperature that is above (rather than below) the accepted safe temperature of the payload; e.g., between 80°F or 85°F and 1 10°F.

[0047] In some embodiments, a carrying case is provided that protects against both hot and cold temperatures. In other words, the carrying case maintains an interior temperature within a safe temperature range, when exposed to either a hot or a cold environment. This is accomplished by the approach described above by including both some PCM with a T pc above the desired temperature and some PCM with a T pc below the desired temperature.

[0048] Thus, in one embodiment, an array or set of PCMs are integrated into a container, carrying bag, or case, where the PCMs have varied phase change temperatures spanning a range of temperatures. For example, consider 390g of encapsulated paraffin PCM divided evenly into ten groups - each with a different phase change temperature, as shown in Table 2.

Table 2. Example of even distribution of phase change temperatures

If all 10 groups of paraffin undergo a phase change by cooling or warming the material through the entire range of phase change temperatures, then 150 J/g x 390g = 58,000 J of heat will be released or absorbed, depending on whether the paraffin is melting or freezing. This is equivalent to 390 g of a material with a specific heat given by

58000J

Specific heat 15 J/

g K- (17)

390 g x (78° -60° ) x - K/°F

This value exceeds the specific heat of liquid water (4.2 J/g-K), liquid ammonia (4.7 J/g-K), and solid lithium (4.4 J/g-K) by considerable margins, which are substances noteworthy for their high specific heats.

[0049] The generalization of Eqn. Effective specific heat (18)

where n is the total number of PCMs, (m pcm ), is the mass of the i'th PCM, (h fusion )i is the specific heat of fusion of the i'th PCM, {m pcm ) to t is the total mass of the PCMs, and AT s the temperature range spanned by the set of phase change temperatures of the constituent materials. If the masses of each of the component PCMs are all equal and the specific heat of the component PCMs are equal (= hf USion ), then Eqn. (18) simplifies to

h

Effective specific heat fusion

AT (19)

In other words, a high effective specific heat can be achieved with an array of PCMs whose phase change temperatures are distributed over a selected temperature range. Fig. 8 indicates the factor by which the effective specific heat of encapsulated paraffin (i.e., h fusion = 150 J/g) exceeds that of liquid water (= 4.2 J/g-K), as a function of the temperature spanned (ΔΤ) by the phase change temperatures. For example, if the phase change temperatures of the groups of encapsulated PCM span 10 °F (i.e. , ΔΤ = 10 °F), then the effective specific heat will be more than six times greater than the specific heat of water.

[0050] The significance of this for the approach disclosed above is revealed by equation (5) and Fig. 2, which demonstrated that the temperature at the interior of the case cover without PCM descends in an exponential way toward the outdoor temperature ( T 0 ) with a time constant of C/K ext , where C is the heat capacity of the enclosed hard case and instrument (i.e., the payload). Since C is the product of the specific heat and mass of the payload, then a PCM array with a distribution of phase change temperatures offers a mechanism for significantly slowing the temperature descent. Plastics and woods have values of specific heat in the vicinity of 2 J/g-K, about half the specific heat of liquid water. Thus, for the above-mentioned temperature span of ΔΤ= 10 °F, the effective specific heat of the encapsulated paraffin is about thirteen times that of the materials used in the hard case and instrument. Therefore, for this span of phase change temperatures, the necessary added mass to increase the time constant of the temperature descent by a given factor would be thirteen times less with PCM than with added hard case mass.

[0051] In one aspect, the carrying case is portable. For purposes herein, the meaning of "portable" is that its size and weight is suitable for carrying by a typical human who would be carrying the payload in which the carrying case is placed. In some embodiments, the weight of the carrying case is less than 10 kg. In some embodiments, the weight of the carrying case is less than 5 or less than 2 kg. Also, for purposes herein, the term "carrying case" means that the case is capable of carrying an object of some reasonable value (e.g., in excess of $100), and that the case extends completely around the object. [0052] Turning to Fig. 9, another embodiment is seen. Carrying case 200 is shown for providing a temperature stabilized environment for an instrument 209 such as, by way of example and not by way of limitation, a clarinet (shown with multiple pieces). Case 200 includes an inner cushioning layer 207 of foam or the like, a PCM layer 210, an insulation layer 220, and an exterior hard shell 270. The hard shell 270 may have one or more latches and hinges 275 or the like, and is generally provided with a handle (not shown). If desired, the hard shell 270 may be covered by a fabric (not shown). Also, if desired, a low emissivity layer (not shown) may be provided between the PCM layer 210 and the insulation layer 220. The insulation 220 may be an aerogel or Styrofoam, since flexibility is not required for this embodiment.

[0053] Another embodiment is seen in Figs. 10a and 10b where a carrying case 300 defining an enclosure 301 is shown which is similar to the carry bag or case cover 100 of Figs. 3a-3d and 4, except that the PCM layer is formed as inserts that are removable from the case. More particularly, case cover 300 utilizes two removable thermal inserts 310a, 310b that enclose PCM for absorbing and releasing energy, and an outer insulation layer 320. The thermal inserts 310a, 310b (which are optionally covered by fabric coverings 312a, 312b) are coupled to the insulation layer 320 by hook and loop fasteners (Velcro) 325. If desired, a low emissivity layer 330, comprising a thin fabric covering 305 and a low emissivity sheet such as Temptrol, may be located between the PCM inserts 310a, 310b and the insulation layer 320, and the fasteners 325 may be affixed (e.g., sewed) to the PCM inserts 310a, 310b and the low emissivity layer 330. Also, if desired, a wear-resistant and/or water-resistant and/or water vapor impermeable fabric layer 340 may be provided over (outside) the outer insulation layer 320. As seen in Figs. 10a and 10b, the carrying case 300 may be provided with a zipper or other closure means 350, and a handle 360. The handle 360 may be a split handle with one loop attached to each portion of the cover 300a, 300b and may be made from webbing. In addition, the carrying case 300 may be provided with an exterior pocket 390 with a zipper or other closure means 392 for carrying sheet music or personal items, or the like. The carrying case 300 is dimensioned to fit over a relatively hard case, which by way of example only, may be a musical instrument case that includes a handle. The carrying case 300 may optionally, as space allows, accommodate additional items such as a pouch for accessories or reeds or reed knives, or the like.

[0054] In one embodiment, each thermal insert is provided with a fabric or plastic loop 365 which enables removal of the thermal insert from the inside of the carrying case 300 (as seen in Fig. 10b where one insert is removed). Removal of the thermal insert in an indoor environment increases its exposure to the surrounding warm air and enables the insert(s) to more quickly change phase for recharging purposes.

[0055] As seen in Figs. 10b, each insert 310a, 310b may also be provided with a temperature display 370. The temperature display may include a series of liquid crystal temperature indicators (LCTIs) such as RLC Reversible Temperature Indicating Labels (Omega Engineering of Norwalk Connecticut) which present a black color except at specific temperatures where they brighten and present different colors. In one embodiment, a first display 370a includes LCTIs that show a short range or fine resolution such as 62°F to 70°F in increments of two degrees Fahrenheit, and a second display 370b includes LCTIs that show a long range or coarse resolution such as 32°F to 86°F in increments of nine degrees Fahrenheit. One side (e.g., the "back side") of the display 370 is in direct contact with and affixed onto the PCM insert. The other side of the display (e.g., the "front" or "display" side) is visible from the interior of the carrying bag 300 through a window formed by a cutout in each of the fabric coverings 312a and 312b covered by a thin piece of transparent vinyl. In this manner, upon opening the carrying bag 300, a user can easily see the temperature of the PCM, and, thereby, its state of charge and the approximate temperature of the enclosure 301 inside of the carrying case 300. Additionally, the window provides simultaneous direct visual and tactile access to the PCM in its segmented containment which may optionally be transparent, thereby providing the user further observation of the state of charge of the PCM.

[0056] Turning now to Figs. 1 1 a and 1 1 b, another embodiment is seen comprising a foldable, multi-panel PCM thermal unit 410 that, optionally, may be inserted into a carrying bag (not shown) which may include insulation. As seen in Fig. 1 1 b, the foldable PCM unit 410 includes six multi-cell sections or panels that may be defined by seams 41 1. The sections of the PCM unit 410, when folded (as seen in Fig. 1 1 a), constitute a top 410a, a bottom 410b and four sides 410c - 41 Of of an enclosure. One or both sides of each of the sections may be covered with fabric 415 which may act as insulation and/or with insulation (not shown). An instrument case (not shown) may be placed in the enclosure. Hook and loop fasteners 425 may be provided and may extend from three of the sides (e.g., 41 Od, 41 Oe, 41 Of) of the unit to the top side (410a) for securing the enclosure sides 410 in place. The top section 410a may also be provided with a handle 460 so that the unit may be lifted easily in its folded configuration and may be hung in its unfolded configuration. The unit 410 may also be provided with a temperature display 470 that in one embodiment includes one LCTI 470a showing a short range or fine resolution such as 62°F to 70°F and a second LCTI 470b showing a long range or coarse resolution such as 32°F to 86°F. In one embodiment, the temperature display 470 is provided on the top panel 410a of the unit 410. The back side of the temperature display 470 is in contact with the PCMs and the front side of the display 470 is visible to the environment. In one embodiment, the back side of the temperature display 470 is not insulated, whereas the front side of the display is provided with a see-through insulation (e.g., clear vinyl and air layers) to enable direct visual access to the displayed temperature reading and

simultaneous direct visual and tactile access to the PCM to which the display 470 is affixed.

[0057] Fig. 12 is a perspective view diagram of another embodiment of a carrying case pouch 500 with a front panel 501 a, a back panel 501 b, a flap 501 c, and with the front and back panels meeting at three closed edges 502a, 502b, 502c, and the front panel 501 a presenting an opening edge 502d. The three closed edges may be closed by sewing, gluing, or otherwise attaching the panels to each other. In one embodiment, edges 502a and 502c are provided with zippers (not shown) for closing the edges, thereby permitting the pouch to be opened at one or both of those edges. The back panel 501 b and flap 501 c are divided by a seam 503. Both the front and back panels 501 a, 501 b comprise a layer of PCM and an insulation layer. Flap 501 c comprises an insulation layer and optionally a layer of PCM. The PCM layer may be a multi-segmented flexible layer such as a layer of MATVESL PURETEMP as previously described. The insulation layer may be made of a tear resistant, water resistant fabric such as SUR LAST (a trademark of Glen Raven, Inc. of Glen Raven, NC) or CORDURA (a trademark of Invista of Wichita, KS) and/or it may be made from a fiber insulation such as THINSULATE. Where both a fiber insulation layer and fabric layer are utilized, the fiber insulation layer will typically be utilized in between the PCM layer and the fabric layer. If desired, a low emissivity sheet of material may be located between the PCM layer and the insulation layer. Also, if desired, the PCM layer (and where present, the fiber insulation layer and/or the low emissivity layer) may be enclosed in the fabric layer such that the inside of the pouch presents a fabric face. As seen in Fig. 12, the pouch 500 may be provided with a Velcro fastener or other closure means 550 (preferably provided on the edge of the flap 501 c and on the front panel 501 a), and a carrying implement such as a handle and/or (shoulder) strap 560 with clips 560a arranged to clip onto rings 560b. Additionally and optionally, a waterproof zipper or ZIPLOC (a trademark of S.C. Johnson) -type seal 599 may be installed at edge 502d and seam 503 to provide an additional barrier to the passage of water vapor from the pouch interior to the environment (or vice versa), beyond that provided by flap 501 c alone. The pouch 500 is dimensioned to snugly receive a relatively hard case, e.g., of a musical instrument, and to have the flap 501 c fold over the top portion of the front panel 501 a and fasten thereto.

[0058] The pouch 500 may also be provided with a temperature display 570 that in one embodiment includes an LCTI 570a showing a short range or fine resolution such as 62°F to 70°F and a second LCTI 570b showing a long range or coarse resolution such as 32°F to 86°F. The back side of the temperature display 570 is in contact with the PCMs, and the front side of the display is optionally provided with a see-through insulation (e.g., vinyl and air layers). In one embodiment, the temperature display 570 is provided on the front panel 501 a of the pouch 500 between the fastener 550 and the opening edge 502d. In this manner, when the pouch 500 is closed with flap 501 c extending over a portion of the front side 501 a and fastened thereto, the display 570 is covered and insulated from the environment by the flap 501 c. In any event, when the flap 501 c is opened, the display 570 is visible and provides a user with an indication of the temperature of the PCM and simultaneous direct visual and tactile access to the PCM, and, hence, the state of charge of the PCM and approximate temperature inside the pouch.

[0059] An embodiment of a pouch 500' similar to pouch 500 is seen in Fig. 12a, with front and back panels 501 a' and 501 b', each comprised of a layer of insulation and low emissivity sheet enclosed in wear-resistant, water-resistant fabric, with an opening 504' defined between edge 502d' and seam 503' for receiving foldable PCM layer 510'. Foldable PCM layer 510', as seen in Figs. 12a and 12b, is provided with PCM 51 1 ' encapsulated in a segmented flexible sheet or bilaminate package which is optionally covered on one or both sides by fabric 512'. The PCM layer 510' has a fabric fold area 513' with two seams for permitting the PCM layer to be folded on itself and inserted into the pouch 500'. The PCM layer 510' also includes loop handles 561 ' for expediting removal of the PCM layer from the pouch 500' and/or for hanging the PCM layer from a coat hanger or hook for rapid recharge. Removal of the PCM layer from the pouch may also be useful if the carrying case pouch 500' is going to be carried through airport security. In all other respects, pouch 500' may be the same as pouch 500 of Fig. 12.

[0060] In another embodiment, the panels of the pouch 500 (of Fig. 12) may be provided with double layers which are open at edge 502d and seam 503, or along one of edges 502a, 502b, and 502c. Two multi-segmented flexible sheets of PCM (as in Fig. 10a) may be provided for insertion between the double layers of each panel. The double layers may be closed with zippers or Velcro. The PCM layer inserts may be inserted and removed from the pouch.

[0061] Fig. 13 shows the measured temperatures versus time of the instrument and the hard case contained within a prototype of the carrying case pouch 500 of Fig. 12 (with parameter values shown in the right-hand column of Table 3 below) upon removal from an indoor environment of approximately 74 °F and during exposure to an outdoor temperature of 23°F. As seen in Fig. 13, the temperature descent of the hard case is arrested after approximately twenty-four minutes at about 63 °F by the phase change of the PCM. The values of various parameters for this prototype are shown in Table 3 in the right-hand column and are compared to the parameter values of the prototype of Fig. 4 shown in the middle column of Table 3 (values taken from Table 1 ). As seen in Table 3, the pouch prototype 500 had a PCM mass of 840 g (compared to the 390 g of the prototype of Fig. 4) and a lower thermal conductance to the external environment (due to a smaller outer surface area of 0.28 m 2 rather than 0.49 m 2 ). Use of the parameter values in the right-hand column of Table 3 in equation (10) yields a time of 272 minutes (= 4 hours and 32 min.) for freezing of the PCM to be complete for the pouch prototype exposed to an external temperature of 23 °F. As suggested by Fig. 13, the prototype was brought indoors after exposure to 23°F for a period of two hours and twenty-three minutes. Fig. 13 further suggests that if the prototype had been left outdoors beyond this time, arrest of the temperature descent would have continued, and, hence, complete freezing of the PCM had not yet occurred. This is to be expected, since exposure of the prototype to the outdoor temperature was stopped well short of the predicted time of freezing of four hours and thirty-two minutes.

Table 3. Values used in equation (10) to predict how long temperature descent is arrested (i.e., PCM freezing time) during test of two prototypes (see also Figs. 5 and 13)

[0062] It should be appreciated that all of the carrying cases previously described are "portable" which shall be understood to mean that an average non-disabled human of average strength may place an object in the carrying case and transport the carrying case and object without assistance. In one embodiment, the carrying case weighs less than ten pounds. In one embodiment, the carrying case weighs less than seven pounds. In one embodiment, the carrying case weighs less than five pounds. In one embodiment, the carrying case weighs less than four pounds. In one embodiment, the carrying case weighs less than three pounds.

[0063] In one embodiment, a method of transporting a temperature-sensitive instrument, equipment, device or object (hereinafter broadly referred to as "object") includes placing the object (such as a musical instrument) in any of the previously described carrying cases having a plurality of layers, including an inner layer having a phase change material contained in a segmented shell and an outer insulation layer that may also serve as a shock absorber. In one embodiment, a low emissivity layer is located between the phase change material layer and the outer insulation layer, and in one

embodiment, a wear-resistant and water-resistant fabric layer is provided over (outside) the outer insulation layer. The object is carried in its case surrounded by the carrying case from a first location (usually an indoor location) at a first temperature, where the PCM in the carrying case is in a first state (phase), into a location or environment (usually outdoor) at a second temperature which causes the PCM in the carrying case to start changing state to a second state while stabilizing the temperature in the carrying case. Eventually, the carrying case with the object is brought to a second location or environment (usually indoor) having an ambient temperature near or at the first temperature (which for purposes shall be understood to be within 10 °F) , where the carrying case is opened and the object and optionally its case are removed from the carrying case. The carrying case is then left at the second location to recharge such that the PCM changes state from the second state back to the first state.

[0064] It will be appreciated that where the carrying case is used to protect objects against the cold, the first state (phase) is generally liquid, and the second state (phase) is generally solid.

[0065] There have been described and illustrated herein several embodiments of a portable apparatus utilizing phase change materials to create a temperature stabilized environment and method of using the same. While particular embodiments have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while particular embodiments of a carrying case for particular musical instruments have been described, it will be appreciated that the embodiments can apply to carrying cases for other musical instruments such as bassoons, violins, cellos, double basses, or other instruments, as well as to provide a temperature stabilized environment for other sensitive and/or expensive objects. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed.