# Patent

## Title
Phase change material bladder for use in a temperature controlled product shipper

## Abstract

A phase change material (PCM) bladder is provided for use in a temperature controlled product shipper. The PCM bladder includes a bladder chamber having a filling port and is configured to receive and hold a flowable phase change material, such as an ice slurry, which can be pumped into the bladder at the point of packaging.

## Background
FIELD OF THE INVENTION
The instant invention relates to temperature controlled product shippers, and more particularly to a phase change material (PCM) bladder for use in a temperature controlled product shipper. More specifically, the invention relates to a PCM bladder or bladder system for use in a “cold-chain” product shipper.
SUMMARY OF THE INVENTION
Throughout this specification, the exemplary embodiments refer to product shippers which are typically maintained at controlled temperatures below ambient temperature, i.e. cold-chain applications. However, while the focus of the exemplary embodiments is on “cold chain” packaging, it is to be understood that the concepts as disclosed herein are equally applicable to product shippers which are to be maintained at controlled temperatures above ambient, even though not specifically discussed herein.
Currently, phase change materials (PCM's) in the form of gel packs or gel bricks are used to heat or cool the interior of a temperature controlled product shipper. Engineers calculate the heat loss of a product shipper design based on a client's desired “target” temperature. The engineers then use a mixture of “ambient” temperature gel packs and “frozen” or “heated” gel packs to achieve the desired results. Before use, the gel packs must be preconditioned to a temperature designated by the engineer who designed the package. For example, in most cold chain applications, there are two temperatures used: −20° C. and +5° C.
As indicated above, the most advantageous use of the invention is in cold chain applications, because there is a tremendous expense involved in pre-conditioning these gel packs at the desired temperatures and then maintaining the gel packs at temperature prior to pack-out.
In this regard, the instant invention provides a novel phase change material (PCM) bladder which is designed and configured to receive and hold a flowable PCM at the point of packaging, thus completely eliminating the need to pre-condition and store large volumes of PCM gel packs.
In a first embodiment, the PCM bladder includes a single bladder chamber having a filling port. The bladder is constructed from overlaid polyethylene sheets which are heated sealed around the peripheral edges. The filling port comprises a filling bung which is sealed to the top sheet and a stopper removably seated in the bung hole. To accommodate the rectangular shape of most typical product boxes, the bladder is formed in the shape of a cross including a central body portion and appendage portions extending outwardly therefrom. The central portion and appendage portions effectively overlay five (5) of the six (6) sides of the product box. An alternate version is asymmetrical and effectively overlays all six (6) sides of the product box. The bladder chamber is configured so that it has a substantially uniform thickness when filled with the flowable PCM whereby the bladder provides a substantially uniform thermal profile around all sides of the product box.
In a second embodiment, a PCM bladder system is provided comprising two discrete PCM bladders which are overlaid in coextensive relation to provide a desired thermal profile. The first bladder receives a PCM pre-conditioned at a first temperature while the second bladder receives a PCM pre-conditioned at a second temperature. The first, or inner, bladder includes a first filling port sealed on the upper sheet, while the second, or outer, bladder includes a second filling port sealed on the upper sheet and further includes an aperture through which the first filling port extends when the second bladder is overlaid on top of the first bladder. Both bladders are formed in the shape of crosses in the exemplary embodiments.
In a third embodiment, a dual chamber PCM bladder is provided in a single heat sealed construction. The dual chamber PCM bladder comprises a first bladder chamber having a first filling port and a second bladder chamber having a second filling port. Each bladder receives a flowable PCM preconditioned at a predetermined temperature. The bladder comprises a lower sheet, a middle sheet and an upper sheet overlaid in substantially coextensive relation and sealed around the peripheral edges thereof. The first bladder chamber is defined between the lower sheet and the middle sheet and the second bladder chamber is defined between the middle sheet and the upper sheet. The first filling port is sealed on the upper surface of the middle sheet and the upper sheet is sealed around the peripheral edge of the first filling port. The second filling port is sealed on the upper surface of the upper sheet whereby the first and second filling ports are both accessible for filling from above the upper surface of the upper sheet. The bladder is preferably formed in the shape of a cross as described hereinabove.
A fourth embodiment comprises a PCM bladder that includes a plurality flutes which divide the chamber, or chambers, into a plurality of sections for greater support and stability of the bladder.
A fifth embodiment comprises a more rigid blow molded box structure which is open at the top for receiving the product box therein.
Accordingly, among the objects of the instant invention are: the provision of a phase change material bladder for use in a temperature controlled product shipper; the provision of a PCM bladder that receives and holds a flowable PCM; the provision of a bladder having a filling port that can be selectively accessed for filling of the bladder chamber with a PCM at the point of packing; the provision of a bladder system including overlaid first and second bladders which received PCM's preconditioned at two different temperatures; the provision of a dual chamber PCM which provides two different PCM's in a single layered construction; and the provision of a PCM bladder including flutes which divide the bladder chamber into a plurality of sections to provide support and stability to the structure.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings which illustrate the best mode presently contemplated for carrying out the present invention:
FIG. 1 is a perspective view of a first embodiment of a phase change material (PCM) bladder constructed in accordance with the teachings of the present invention;
FIG. 2 is top view thereof;
FIG. 3 is a cross-sectional view thereof taken along line 3-3 of FIG. 2;
FIG. 4 is a perspective view of a filling port;
FIG. 5 is a perspective view of the PCM bladder and a representative product box where the PCM bladder overlays five (5) of the six (6) sides of the product box;
FIG. 6 is an exploded perspective view of a temperature controlled product shipper including the PCM bladder of the present invention;
FIG. 7 is a perspective view of an asymmetrical PCM bladder effective for overlaying six (6) sides of the product box;
FIG. 8 is another perspective view thereof as shown in its deployed configuration;
FIG. 9 is a perspective view of a second embodiment comprising a PCM bladder system having two discrete PCM bladders which are overlaid in coextensive relation;
FIG. 10 is another perspective view thereof as shown in their deployed configurations;
FIG. 11 is an exploded perspective view of a temperature controlled product shipper including the present 5-sided PCM bladder system;
FIG. 12 is a perspective view of an asymmetrical PCM bladder system effective for overlaying six (6) sides of the product box;
FIG. 13 is another perspective view thereof as shown in their deployed configurations;
FIG. 14 is an exploded perspective view of a temperature controlled product shipper including the 6-sided PCM bladder system;
FIG. 15 is a perspective view of another alternative bladder system effective for overlaying the four side surfaces of the product box;
FIG. 16 is an exploded perspective view thereof;
FIG. 17 is a perspective view of a third embodiment comprising a dual chamber PCM bladder formed as a single heat sealed construction;
FIG. 18 is a top view thereof;
FIG. 19 is a cross-section view thereof taken along line 19-19 of FIG. 18;
FIG. 20 is an exploded perspective view thereof;
FIG. 21 is a perspective view of an asymmetrical dual chamber PCM bladder effective for overlaying six (6) sides of the product box;
FIG. 22 is a perspective view of a fourth embodiment comprising a dual chamber bladder including a plurality of flutes which divide the bladders into a plurality of sections; and
FIG. 23 is a perspective view of a fifth embodiment comprising a more rigid blow-molded PCM bladder.



DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
Referring now to the drawings, a first embodiment of a phase change material bladder of the instant invention is illustrated and generally indicated at 10 in FIGS. 1-6. As will hereinafter be more fully described, the instant invention provides a novel phase change material (PCM) bladder which is designed and configured to receive and hold a “flowable PCM” 12 at the point of packaging, thus completely eliminating the need to pre-condition and store PCM gel packs.
The term “phase change material” (PCM) as used within the specification refers to a material having a high heat of fusion which, when melting or solidifying at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid and vice-versa.
The term “flowable PCM” as used within the specification refers to a PCM material which can be pumped with conventional pumping devices from a storage tank or container into the PCM bladder 10 as described herein. At the present time, the exemplary embodiment of a “flowable PCM” comprises a “slurry ice” material that is produced on-site and pumped through insulated hoses to a filling head. However, the inventive concepts herein should not be limited to any specific “flowable PCM”.
In the present disclosure, slurry ice is produced by a crystal ice generator (not shown) and held in a storage tank (not shown). A brine is incorporated into the “ice” solution to increase the “flowability” of the “ice” solution. Pumping stations (not shown) are employed to deliver the slurry ice to pack-out stations as needed.
Referring briefly to FIGS. 5 and 6, the present PCM bladder 10 is designed to be useful in a temperature controlled product shipper generally indicated at 14. The product shipper 14 comprises an interior product box 16, or mastercase, as it is sometimes called, an insulated liner 18 (which includes a lid 18A) and an outer box 20. The product box 16 is designed to hold the “temperature sensitive product”. The product box 16 is received inside the insulated liner 18, and the PCM bladder 10 is received into a space defined between the inside surface of the insulated liner 18 and the outside surface of the product box 16.
Turning now to the PCM bladder 10, in a first embodiment, the PCM bladder 10 includes a single bladder chamber 22 having a filling port 24. The bladder 10 is constructed from polyethylene sheets 26, 28 which are overlaid in substantially coextensive adjacent relation and heated sealed around the peripheral edges to form the interior bladder chamber 22. Referring to FIG. 2A, the bladder chamber 22 is configured so as to have a substantially uniform thickness “t” across its extent when filled with the flowable PCM 12.
The filling port 24 comprises a filling bung 30 which is sealed to the top sheet 26 and a stopper 32 removably seated in the bung hole 34 (FIG. 4). It is noted that the PCM bladder 10 is intended to be filled at the point of shipment, where the PCM bladder 10 is inserted into the shipper 14 with the liner lid 18A off and outer box 20 still open. In this regard, the filling port 24 is presented for filling on the top of the shipper 14 where it can be accessed by an automated filling apparatus (not shown). In use, the filling bung 30 is grabbed by an automated, robotic filling head which removes the stopper 32, fills the bladder chamber 22 with a desired PCM 12, and replaces the stopper 32. It should be noted that a variety of different types of filling ports 24 can be utilized depending on the application and needs of the end user, and the concepts herein should not be limited only to a filling bung with a removable stopper.
To accommodate the rectangular shape of most typical product boxes 16, the bladder 10 is formed in the shape of a cross including a central body portion 36 and appendage portions 38 extending outwardly therefrom (See FIG. 2). The central body portion 36 and appendage portions 38 effectively overlay five (5) of the six (6) sides of the product box 16 (See FIG. 5).
An alternate version indicated at 10A in FIGS. 7 and 8, is asymmetrical and effectively overlays all six (6) sides of the product box 16. The bladder chamber 22 in this version is also configured so that it has a substantially uniform thickness when filled with the flowable PCM 12 whereby the bladder 10A provides a substantially uniform thermal profile around all six (6) sides of the product box (See FIG. 8).
While the exemplary embodiment illustrated a rectangular shaped product box 16 and associated shape for the PCM bladder 10, it should be understood that the shape of the bladder 10 may be altered to accommodate other product box shapes, such as for example, a cylinder. In the case of a cylindrical product box (not shown), the PCM bladder may comprise a circular central portion and appendages which extend radially outward from the central portion.
Referring now to FIGS. 9-11, in a second embodiment, a PCM bladder system 100 comprises two discrete PCM bladders 102, 104 which are overlaid in coextensive relation and cooperate to provide a desired thermal profile. The bladders 102, 104 are constructed in the same manner as in the first embodiment described above. However, the first bladder 102 receives a PCM pre-conditioned at a first temperature while the second bladder 104 receives a PCM pre-conditioned at a second temperature.
Referring to FIG. 9, the first, or inner, bladder 102 includes a first filling port 106 sealed on the upper sheet, while the second, or outer, bladder 104 includes a second filling port 108 sealed on the upper sheet and an aperture 110 through which the first filling port 106 extends when the second bladder 104 is overlaid on top of the first bladder 102 (See FIG. 10). Both bladders 102, 104 are formed in the shape of crosses in the exemplary embodiments to overlay 5 outer sides of the product box 16. The dual bladder PCM system 100 is received into a product shipper 14 as described hereinabove (See FIG. 11).
An alternate version indicated at 100A in FIGS. 12-14, provides asymmetrical first and second PCM bladders 102A and 104A and effectively overlays all six (6) sides of the product box 16. The six-sided, dual-bladder PCM system 100A is also received into a product shipper 14 as described hereinabove (See FIG. 14).
Yet another alternate version indicated at 100B in FIGS. 15-16, provides first and second linear PCM bladders 102B and 104B which are effective for overlaying the four side surfaces of the product box 16 leaving the top and bottom surface uncovered. The filling ports 106B, 108B on these linear PCM bladders are positioned in the side edges so that they are accessible from the top of the shipper.
In a third embodiment as illustrated in FIGS. 17-20, a dual chambered PCM bladder 200 is provided in a single heat sealed construction. The dual chamber PCM bladder 200 comprises a first bladder chamber 202 having a first filling port 204 and a second bladder chamber 206 having a second filling port 208. Each bladder chamber 202, 206 receives a flowable PCM 210, 212 preconditioned at a predetermined temperature.
The dual chambered bladder 200 comprises a lower sheet 214, a middle sheet 216 and an upper sheet 218 overlaid in substantially coextensive relation and sealed around the peripheral edges thereof to form the two chambers 202, 204. The first bladder chamber 202 is defined between the lower sheet 214 and the middle sheet 216 and the second bladder chamber 206 is defined between the middle sheet 216 and the upper sheet 218. The first filling port 204 is sealed at aperture 205 on the upper surface of the middle sheet 216 and the upper sheet 218 is sealed around the peripheral edge of the first filling port 204. The second filling port 208 is sealed at aperture 207 on the upper surface of the upper sheet 218 whereby the first and second filling ports 204, 208 are both accessible for filling from above the upper surface of the upper sheet 218. Referring to FIG. 19, the first and second bladder chambers 202, 206 are both configured so as to have a substantially uniform thickness “t” across its extent when filled with the flowable PCM's 210, 212.
As described hereinabove the PCM bladder 200 is preferably formed in the shape of a cross and is received into a product shipper 14 as described hereinabove.
An alternate version indicated at 200A in FIG. 21, provides asymmetrical first and second bladder chambers and effectively overlays all six (6) sides of the product box 16. The six-sided, dual-chamber bladder 200A is also received into a product shipper as described hereinabove.
A fourth embodiment, as illustrated in FIG. 22, comprises a PCM bladder 300 that includes a plurality of flutes 302 formed by heat sealing the polyethylene sheets together. The flutes 302 divide the appendage portions 38 of the bladder 300 into a plurality of sections and provide support and stability for the PCM within the bladder 300. The bladder 300 may comprise a single chamber bladder or a dual chamber bladder, both as described hereinabove. The flutes 302 may extend vertically, as illustrated, or may be oriented horizontally, or in any other direction which is necessitated by the design of the shipper and/or bladder.
A fifth embodiment, as illustrated in FIG. 23, comprises a slightly more rigid PCM bladder 400 formed from a blow-molded polyethylene material. The PCM bladder 400 may be a single chamber bladder containing a single PCM, or may be a dual chamber PCM bladder containing PCM's preconditioned at two different temperatures. The more rigid material helps maintain the shape of the bladder 400 and provides for a uniform thermal profile. In the configuration as shown, the PCM bladder is formed in the shape of an open box into which the product box (not shown) would be received. The filling ports 402 and 404 are located on the tops of the side walls so that they can be accessed from the top of the shipper.
It can therefore be seen that the present disclosure provides the following unique concepts: a novel phase change material (PCM) bladder for use in a temperature controlled product shipper; a PCM bladder that receives and holds a flowable PCM; a PCM bladder having a filling port that can be selectively accessed for filling of the bladder chamber with a PCM at the point of packing; a dual bladder system including overlaid first and second bladders which receive PCM's preconditioned at two different temperatures; a dual chamber PCM bladder which provides two different PCM's in a single layered construction; and a PCM bladder including flutes which divide the chamber into a plurality of sections to provide support and stability to the structure.
For these reasons, the instant invention is believed to represent a significant advancement in the art which has substantial commercial merit.
While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claims.

## Claims

1. A phase change material bladder for use in a temperature controlled product shipper comprising:
a bladder chamber having a filling port,
said bladder chamber being formed in the shape of a cross having a central body portion and opposed appendage portions extending outwardly therefrom,
said bladder chamber being configured and arranged to receive and retain a flowable phase change material preconditioned at a predetermined temperature,
said bladder chamber being configured and arranged to have a substantially uniform thickness when filled with said flowable phase change material whereby said bladder provides a substantially uniform thermal profile.

2. The bladder of claim 1 wherein said opposed appendage portions are symmetrical, said central portion and said symmetrical opposed appendage portions cooperating to substantially overlay five adjacent surfaces of a product box.

3. The bladder of claim 1 wherein said opposed appendage portions are asymmetrical, said central portion and said asymmetrical opposed appendage portions cooperating to substantially overlay six adjacent surfaces of a product box.

4. A phase change material bladder for use in a temperature controlled product shipper comprising:
a bladder chamber having a filling port,
said bladder chamber including a plurality of flutes which divide said bladder chamber into a plurality of sections,
said bladder chamber being configured and arranged to receive and retain a flowable phase change material preconditioned at a predetermined temperature,
said bladder chamber being configured and arranged to have a substantially uniform thickness when filled with said flowable phase change material whereby said bladder provides a substantially uniform thermal profile.

5. A phase change material bladder system for use in a temperature controlled product shipper comprising:
a first bladder including a first bladder chamber having a first filling port,
said first bladder being configured and arranged to receive and retain a flowable phase change material preconditioned at a first predetermined temperature,
a second bladder including a second bladder chamber and a second filling port,
said second bladder being configured and arranged to receive and retain a flowable phase change material preconditioned at a second predetermined temperature.

6. The bladder system of claim 5 wherein said first and second bladders overlay each other in substantially coextensive adjacent relation.

7. The bladder system of claim 5 wherein said first and second bladders are each configured and arranged to have a substantially uniform thickness when filled with said flowable phase change material whereby said bladder system provides a substantially uniform thermal profile.

8. The bladder system of claim 5 wherein each of said first and second bladders each have a central body portion and appendage portions extending outwardly therefrom.

9. The bladder system of claim 5 wherein said first filling port is located in said central body portion of said first bladder, and further wherein said second filling port is located in said central body portion of said second bladder, said second bladder including an aperture through which said first filling port extends when said second bladder is overlayed on top of said first bladder.

10. The bladder system of claim 5 wherein said first and second bladders are each formed in the shape of a cross having a central body portion and opposed appendage portions extending outwardly therefrom.

11. The bladder system of claim 5 wherein said first and second bladders each include a plurality of flutes which divide said bladders into a plurality of sections.

12. The bladder of claim 10 wherein said opposed appendage portions are symmetrical, said central portion and said symmetrical opposed appendage portions cooperating to substantially overlay five adjacent surfaces of a product box.

13. A phase change material bladder for use in a temperature controlled product shipper comprising:
a first bladder chamber having a first filling port,
said first bladder chamber being configured and arranged to receive and hold a flowable phase change material; and
a second bladder chamber having a second filling port,
said second bladder chamber being configured and arranged to receive and hold a flowable phase change material
wherein said first and second bladder chambers are coextensive and overlay each other.

14. The bladder of claim 13 wherein said first and second bladder chambers are each configured and arranged to have a substantially uniform thickness when filled with said flowable phase change material whereby said bladder provides a substantially uniform thermal profile.

15. The bladder of claim 13 comprising a lower sheet, a middle sheet and an upper sheet overlaid in substantially coextensive adjacent relation and sealed around peripheral edges thereof, said first bladder being defined between said lower sheet and said middle sheet, said second bladder being defined between said middle sheet and said upper sheet.

16. The bladder of claim 15 wherein said first filling port is disposed on an upper surface of said middle sheet and said upper sheet is sealed around a peripheral edge of said first filling port, and further wherein said second filling port is disposed on an upper surface of said upper sheet, whereby said first and second filling ports are both accessible for filling said first and second bladder chambers from above said upper surface of said upper sheet.

17. The bladder of claim 13 wherein said first and second bladder chambers are formed in the shape of a cross having a central body portion and opposed appendage portions extending outwardly therefrom.

18. The bladder of claim 17 wherein said opposed appendage portions are asymmetrical, said central portion and said asymmetrical opposed appendage portions cooperating to substantially overlay six adjacent surfaces of a product box.

19. The bladder of claim 13 further including a plurality of flutes which divide said first and second bladder chambers into a plurality of sections.

20. A phase change material bladder for use in a temperature controlled product shipper comprising:
a first bladder chamber having a first filling port,
said first bladder chamber being configured and arranged to receive and hold a flowable phase change material; and
a second bladder chamber having a second filling port,
said second bladder chamber being configured and arranged to receive and hold a flowable phase change material,
wherein said first bladder chamber receives a phase change material preconditioned at a first temperature, and said second bladder chamber receives a phase change material preconditioned at a second temperature.

21. The bladder of claim 20 wherein said first and second bladder chambers are each configured and arranged to have a substantially uniform thickness when filled with said flowable phase change material whereby said bladder provides a substantially uniform thermal profile.