Abstract
A thermally insulated container for storing and serving frozen confectionery items, wherein the container is preferably arranged to be removably mounted within a service cart, such as an inflight service cart.
Claims
1. Thermally insulated container for storing and serving frozen confectionery items, the container comprising: a thermally insulated housing (1) defining an insulated chamber (2), the thermally insulated housing (1) having at least one openable side (18) to allow access to the chamber (2), a product storage assembly (4) mounted within the insulated chamber (2), the product storage assembly (4) comprising: a frame (5) having at least three walls thereby delineating a three-sided perimeter, at least one product container (7, 21) for containing a plurality of the frozen confectionery items, the at least one product container (7, 21) being positioned within the frame (5), at least a first reservoir of phase change material (6), positioned in contact with the frame (5) or the product container (7, 21), wherein the product storage assembly (4) is mounted such that it is separated from the thermally insulated housing by a gap (13), the gap (13) having a width of 1 mm to 10 mm, wherein the gap (13) is present over at least 80% of the internal surface area of the thermally insulated housing.
2. Thermally insulated container as claimed in claim 1 wherein the gap (13) is present over at least 90%, preferably at least 95% of the internal surface area of the thermally insulated housing.
3. Thermally insulated container as claimed in claim 1 wherein the product storage assembly (4) comprises a thermally conductive boundary having at least three sides which are in thermal contact with one another during storage of the frozen confectionery items, the thermally conductive boundary being provided by the frame (5) and/or the at least one product container (7, 21) and wherein the reservoir of phase change material (6) is positioned in thermal contact with the thermally conductive boundary.
4. Thermally insulated container as claimed in claim 3 wherein the frame (5) is made from a material with low thermal conductivity, and the product container (7, 21) provides the thermally conductive boundary.
5. Thermally insulated container as claimed in claim 3 wherein the product container (7, 21) is made from a material with low thermal conductivity, and the frame (5) provides the thermally conductive boundary.
6. Thermally insulated container as claimed in claim 1 wherein the frame (5) has four or five walls thereby delineating a four-sided or five-sided perimeter.
7. Thermally insulated container as claimed in claim 1 wherein the gap (13) has a width of 2 to 8 mm, preferably 3 to 5 mm.
8. Thermally insulated container as claimed in claim 1 wherein the product storage assembly (4) additionally comprises a second reservoir of phase change material (8, 8a, 8b, 8c) positioned in contact with the frame (5) or the product container (7, 21).
9. Thermally insulated container as claimed in claim 1 wherein the container additionally comprises dry ice (15) positioned in contact with the reservoir of phase change material (6, 8, 8a, 8b, 8c), preferably on top of the first reservoir of phase change material (6).
10. Thermally insulated container as claimed in claim 1 wherein the product container (7, 21) is a shelf, a tray, a drawer, a box, a carton, or an insulated bag.
11. Thermally insulated container as claimed in claim 10 wherein the product container (7, 21) is engageable with the frame (5) such that the product container can be moved relative to the frame in a slidable manner between an open position and a closed position.
12. Thermally insulated container as claimed in claim 1 wherein the thermally insulated housing (1) comprises a material selected from: expanded polypropylene (EPP), polyurethane (PU), Aerogel, and vacuum panels.
13. A service cart (22), preferably an inflight service cart, comprising at least one insulated container as claimed in claim 1.
14. A method for storing and serving frozen confectionery items using a thermally insulated container as claimed in claim 1, the method comprising: cooling the reservoir(s) of phase change material (6, 8, 8a, 8b, 8c) to a temperature of less than −6° C.; mounting the product storage assembly (4) within the insulated chamber (2) of the thermally insulated housing (1) such that the cooled reservoir(s) of phase change material (6, 8, 8a, 8b, 8c) are in contact with the frame (5) or the product container (7, 21), and the product container (7, 21) is loaded with a plurality of frozen confectionery items; wherein the product storage assembly (4) is mounted such that it is separated from the thermally insulated housing (1) by a gap (13), the gap (13) having a width of 1 mm to 10 mm, wherein the gap (13) is present over at least 80% of the internal surface area of the thermally insulated housing; storing the frozen confectionery items within the insulated chamber (2) for a period of up to 24 hours and serving the frozen confectionery items during the storage period by opening the openable side (18) of the thermally insulated housing (1) and removing at least one of the frozen confectionery items from the insulated chamber (2), and then preferably closing the openable side (18) of the thermally insulated housing (1).
15. Method for storing and serving frozen confectionery items as claimed in claim 14 wherein: the frozen confectionery items are loaded into a product container (7, 21) that is engageable with the frame (5) such that the product container (7, 21) can be moved relative to the frame (5) in a slidable manner between an open position and a closed position; and the frozen confectionery items are served by opening the openable side (18) of the thermally insulated housing (1), sliding the product container (7, 21) to the open position and removing at least one of the frozen confectionery items, and then preferably sliding the product container (7, 21) to the closed position and closing the openable side (18) of the thermally insulated housing (1).
Description
FIGURES
[0053] By way of example, the present invention is illustrated with reference to the following figures, in which:
[0054] FIGS. 1a to 1c show cross-sectional schematic views of a thermally insulated container according to the invention viewed from the front. Specifically, FIGS. 1a and 1b show elements which are assembled to provide the container shown in FIG. 1c.
[0055] FIG. 1d shows a cross-sectional schematic view of arrangement A from Example 1 viewed from the front.
[0056] FIGS. 2a, 2b and 2c show cross-sectional views of the three arrangements assessed in Example 2 viewed from the front.
[0057] FIGS. 3a to 3b are cross-sectional views which schematically illustrate further insulated containers according to the invention viewed from the front.
[0058] FIGS. 4a, 4c and 4e are cross-sectional views which schematically illustrate additional insulated containers according to the invention viewed from the side.
[0059] FIGS. 4b, 4d and 4f are cross-sectional views which schematically illustrate the insulated containers of FIGS. 4a, 4c and 4e viewed from the front.
[0060] FIG. 5 is a perspective view of a service cart containing two insulated containers.
[0061] FIG. 6 shows the average temperature curves for the arrangements of Example 1.
[0062] FIG. 7 shows the average temperature curves for the arrangements of Example 2.
[0063] FIG. 1a is a cross-sectional view of a thermally insulated housing (1) defining an insulated chamber (2) viewed from the front. The thermally insulated outer housing (1) is made of EPP, and has a hinged front panel (not shown) to allow access to the insulated chamber (2). The outer housing (1) has two moulded grooves (3a, 3b). It will be appreciated that further groove(s) could additionally be present.
[0064] FIG. 1b is a cross-sectional view of a product storage assembly (4) which includes a frame (5), a first reservoir of phase change material (6), a product container (7)—in this case a product drawer—and three additional reservoirs of phase change material (8a, 8b, 8c). The frame (5) has an upper wall (9) and a lower wall (10) which are connected by two side walls (11a, 11b); the frame additionally comprises a rear wall (not shown) and thereby delineating a five-sided boundary. Each of the reservoirs of phase change material (6, 8a, 8b, 8c) consists of a rigid plastic shell filled with phase change material, preferably eutectic material. The upper wall (9) of the frame (5) is attached to the plastic shell of the first reservoir of phase change material (6). This ensures that the first reservoir of phase change material (6) is in contact with the frame (5). The rigid shell of the first reservoir of phase change material (6) has two protruding side ribs (12a, 12b). These ribs (12a, 12b) interact with the moulded grooves (3a, 3b) of the housing, as can be seen in FIG. 1c. The product drawer sits on the lower wall (10) of the frame (5). The sidewalls (11a, 11b) and the lower wall (10) of the frame are each attached to one of the three additional reservoirs of phase change material (8a, 8b, 8c). Thus, the additional reservoirs of phase change material (8a, 8b, 8c) are also in contact with the frame (5).
[0065] FIG. 1c is a cross-sectional view of a thermally insulated container according to the invention which has been assembled by mounting the product storage assembly (4) of FIG. 1b within the thermally insulated housing (1) of FIG. 1a. More precisely, the product storage assembly (4) has been mounted within the thermally insulated housing (1) by engaging the protruding side ribs (12a, 12b) with the moulded grooves (3a, 3b). Since the upper wall (9) of the frame (5) is attached to the shell of the first reservoir of phase change material (6), the frame (5) “hangs” within the thermally insulated chamber (2). This allows the product storage assembly (4) to be mounted within the insulated chamber (2) such that there is an air gap (13) between the thermally insulated housing (1) and the product storage assembly (4). There is an air gap of 2 to 3 mm around all sides of the assembly. The only contact points between the product storage assembly (4) and the thermally insulated housing (1) of FIG. 1a are the side ribs (12a, 12b) and the moulded grooves (3a, 3b). Since the side ribs (12a, 12b) are made from a thermally insulating material, there is little thermal energy transfer between the first reservoir of phase change material (6) and the outer housing (1).
[0066] FIG. 1d shows a cross-sectional schematic view of the control arrangement from Example 1. This arrangement includes a first reservoir of phase change material (6) and a product container (7). However, there is no frame (5). The product container (7)—in this case a product drawer—sits on two thin strips of polystyrene (P1, P2) placed on the base of the insulated housing (1).
[0067] FIGS. 2a, 2b and 2c show cross-sectional views of further thermally insulated containers viewed from the front. In each case, the thermally insulated housing (1) is made of EPP, and has a hinged front panel (not shown) to allow access to the insulated chamber (2). The frame (5) is made from aluminium and has a thickness of 2 mm. The frame (5) has an upper wall (9) and a lower wall (10) which are connected by two side walls (11a, 11b), thereby delineating a four-sided thermally conductive boundary. In addition, each side wall (11a, 11b) has a projection (14a). These projections (14a) support product container (7) (in this case a product drawer), thereby enabling the product container to slide between a closed position (where it is enclosed within the frame) and an open position. Of course, the projections (14a) could equally support a shelf (not shown). The product drawer (7) is made of aluminium and can hold a plurality of frozen confectionery items (not shown). Only a single product drawer (7) is shown in each of FIGS. 2a, 2b and 2c. Nevertheless, it will be appreciated that an additional product drawer could be positioned in the lower part of the frame, i.e. supported by projections (14b).
[0068] The first reservoir of phase change material (6) has the same construction as that described above in relation to FIG. 1, and the frame (5) is attached to it in the same manner. Once again, the rigid shell of the first reservoir of phase change material (6) has two protruding side ribs (12a, 12b), which interact with moulded grooves of the outer housing, thus enabling the frame to “hang” within the insulated chamber such that there is an air gap (13) between the thermally insulated outer housing (1) and the thermally conductive inner frame (5). There is an air gap of 2 to 3 mm around all sides of the frame. The only contact points between the product storage assembly (i.e. frame (5)+first reservoir of phase change material (6)+product drawer (7)) and the housing (1), are the ribs (12a, 12b) and the moulded grooves (3a, 3b). As such, there is an air gap (13) present between the product storage assembly (4) and the outer housing (1).
[0069] The thermally insulated containers of FIGS. 2a and 2c both include a second reservoir of phase change material (8), which is positioned in the lower part of the frame—specifically so as to contact the lower wall (10) of the frame (5). As such, it will be apparent that the second reservoir of phase change material (8) is in thermal contact with the thermally conductive boundary provided by the frame (5). Should an additional product drawer be provided in either of these containers, it would be positioned in the lower part of the frame, i.e. supported by projections (14b). Of course, projections (14b) are not essential, and it will be apparent that these projections could be omitted from the arrangements. For example, if these projections (14b) were omitted from the arrangement of FIG. 2b, then there would be additional space for the product drawer (7) since it would now sit on the lower wall (10) of the frame (5).
[0070] The thermally insulated containers of FIGS. 2b and 2c both include dry ice (15), which is positioned on top of the first reservoir of phase change material (6).
[0071] FIGS. 3a to 3d are schematic cross-sectional views which illustrate further insulated containers according to the invention (as viewed from the front).
[0072] FIG. 3a shows an insulated housing (1) with a three-sided frame (5) mounted therein. The frame (5) has two side walls (11a, 11b) connected by upper wall (9), thereby delineating a three-sided perimeter. The upper wall (9) interacts with the moulded grooves of the outer housing (1), thus enabling the frame to “hang” within the insulated chamber. The only contact points between the product storage assembly and the insulated housing (1) are where the upper wall (9) interacts with the moulded grooves. Each sidewall (11a, 11b) has a projection (14a). Product drawer (7) has a ridge (16) at the upper edge of each side, and engages with the projections (14a) of the frame (5) in a slidable manner by way of these ridges (16) such that the product drawer (7) is suspended from the frame (5). The first reservoir of phase change material (6) is attached to the base of the product drawer (7). Although not shown, it will be apparent that the first reservoir of phase change material (6) could simply be placed in the base of the product drawer (7).
[0073] FIG. 3b illustrates an insulated housing (1) with a different version of a three-sided frame (5) mounted therein. In this instance, the frame (5) has two side walls (11a, 11b) connected by lower wall (10), thereby delineating a three-sided perimeter. The frame (5) is shaped so as to have arms (17) which interact with moulded grooves of the outer housing (1), thus enabling the frame to “hang” within the insulated chamber such that there is an air gap (13) between the thermally insulated outer housing (1) and the frame (5). Product drawer (7) sits on the lower wall (10) of the frame (5). The first reservoir of phase change material (6) is provided in the format of a removeable lid which closes the top of the product drawer (7). The lid can be removed to allow access to the products within the drawer (7).
[0074] FIG. 3c shows another possible arrangement of a product storage assembly mounted within an insulated housing (1). The frame is similar to that described above with reference to FIG. 3b, only in this instance each side wall (11a, 11b) has a projection (14b). These projections (14b) support product drawer (7), thereby enabling the product container to slide between a closed position (where it is enclosed within the frame) and an open position. The first reservoir of phase change material (6) contacts the lower wall (10) of the frame (5). The projections (14b) prevent the product drawer (7) contacting the first reservoir of phase change material (6).
[0075] FIG. 3d shows an insulated housing (1) with a three-sided frame (5) mounted therein. The frame (5) has two side walls (11a, 11b) connected by upper wall (9), thereby delineating a three-sided perimeter. Each sidewall (11a, 11b) has a projection (14a). The first reservoir of phase change material (6) has the same construction as that described above in relation to FIG. 1, and the frame (5) is attached to it in the same manner. Once again, the rigid shell of the first reservoir of phase change material (6) has two protruding side ribs (12a, 12b), which interact with moulded grooves of the outer housing, and the frame to “hangs” within the insulated chamber. These are the only contact points between the housing (1) and the product storage assembly (4). Product drawer (7) has the same construction as described above with reference to FIG. 3a, and engages with the projections (14a) of the frame (5) in a slidable manner by way of ridges (16) such that the product drawer (7) is suspended from the frame (5).
[0076] FIG. 4 shows a series of cross-sectional views which schematically illustrate additional insulated containers according to the invention. Since the gap (13) must be present over at least 80% of the internal surface area of the thermally insulated housing, it may be necessary to include a feature which helps to prevent the front of the drawer from contacting the housing. For example, the frame may include a releasable catch which interacts with the drawer (7) holding it in the closed position. Additionally or alternatively, the door component (18) may include a projection which abuts against the drawer (7) to hold it in its closed position when the door component is closed.
[0077] FIG. 4a illustrates a first such insulated container viewed from the side. FIG. 4b shows the same container viewed from the front. The insulated housing (1) has an openable side in the format of a door component (18), which moves between open and closed positions via hinge (19). The openable side (18) is shown in the closed position. The container includes a three-sided frame (5), having an upper wall (9) and a lower wall (10) connected by rear wall (20), thereby delineating a three-sided perimeter. The upper wall (9) interacts with moulded grooves in the outer housing (1), thus enabling the frame (5) to “hang” within the insulated chamber (2), and maintaining a gap (13) between the product storage assembly. The only contact points between the product storage assembly and the insulated housing (1) are where the upper wall (9) interacts with the moulded grooves. Product drawer (7) sits on the lower wall (10) of the frame (5). The first reservoir of phase change material (6) is attached to the rear wall of the of the product drawer (7). It is possible for the lower wall (10) of the frame (5) to include a lip (not shown) along at least a portion of each of the sides to help keep the drawer (7) in position.
[0078] FIG. 4c illustrates a further insulated container viewed from the side. FIG. 4d shows the same container viewed from the front. The insulated housing (1) has an openable side in the format of a door component (18), which moves between open and closed positions via hinge (19). The container includes a five-sided frame (5), having an upper wall (9) and a lower wall (10) connected by rear wall (20) and by two side walls (11a, 11b), thereby delineating a five-sided perimeter. The first reservoir of phase change material (6) has the same construction as that described above in relation to FIG. 1, and the frame (5) is attached to it in the same manner. Once again, the rigid shell of the first reservoir of phase change material (6) has two protruding side ribs (12a, 12b), which interact with moulded grooves of the outer housing, and the frame to “hangs” within the insulated chamber. These are the only contact points between the housing (1) and the product storage assembly (4). In this instance the product containers are shelves (21), which are supported on projections (14a, 14b) on the side walls (11a, 11b).
[0079] FIG. 4e illustrates a further example of an insulated container viewed from the side. FIG. 4f shows the same container viewed from the front. The insulated housing (1) has an openable side in the format of a door component (18), which moves between open and closed positions via hinge (19). The container includes a three-sided frame (5), having an upper wall (9) and a lower wall (10) connected by rear wall (20), thereby delineating a three-sided perimeter. The first reservoir of phase change material (6) has the same construction as that described above in relation to FIG. 1, and the frame (5) is attached to it in the same manner. Once again, the rigid shell of the first reservoir of phase change material (6) has two protruding side ribs (12a, 12b), which interact with moulded grooves of the outer housing, and the frame to “hangs” within the insulated chamber so as to maintain gap (13). These are the only contact points between the housing (1) and the product storage assembly (4). Product drawer (7) sits on the lower wall (10) of the frame (5). Once again, it is possible for the lower wall (10) of the frame (5) to include a lip (not shown) along at least a portion of each of the sides to help keep the drawer (7) in position.
[0080] FIG. 5 is a perspective view of a service cart (22) with two insulated outer housings (1) mounted therein (one above the other). In this view the reservoirs of phase change material and the inner frame are not in situ. Each outer housing (1) comprises a hinged door component (18) which is openable to allow access to the insulated chamber (2).
[0081] The invention is not limited to the embodiments illustrated in the figures. Accordingly, it should be understood that where features mentioned in the claims are followed by reference numerals, such numerals are included solely for the purpose of enhancing the intelligibility of the claims and are in no way limiting to the scope of the claims.
[0082] The following examples are intended to illustrate the invention and are not intended to limit the invention to those examples per se.
EXAMPLES
[0083] In Examples 1 and 2 the thermally insulated housing was an insulated EPP box with a hinged front panel to allow access to the insulated chamber (ATLAS 1/3 cooling chest in Example 1; ATLAS 1/2 chest in Example 2; both from Icebridge Cooling Solutions). In both examples, the first reservoir of phase change material was provided by filling a plastic cooling cassette (Icebridge Cooling Solutions) with 1.3 kg eutectic material (E-19 from PCM Products Ltd; phase change temperature −18.7° C.). The cassettes are designed to be received by the insulated boxes and have protruding ribs extending along each side which are received by corresponding grooves moulded into the internal walls of the insulated housing.
Example 1
[0084] The properties of three thermally insulated container arrangements were investigated. All three arrangements include a first reservoir of phase change material provided by filling a plastic cooling cassette with 1.3 kg eutectic material as set out above.
[0085] Arrangement 1 is illustrated in FIG. 1c and has an air gap of 2 to 3 mm around all sides of the product storage assembly. Two versions of this arrangement were compared: one with a five-sided PVC frame and one with a 5-sided aluminium frame. In both cases, additional reservoirs of phase change material were attached to the rear wall, bottom wall and side walls of the frame and the front of the product drawer (totalling 1.677 kg of additional eutectic material). In the version of arrangement 1 with the aluminium frame, the product drawer had an aluminium plate between the front of the product drawer and the reservoir of phase change material attached thereto. Arrangement 1 maintains the gap around all sides of the product storage assembly, even with the presence of the additional reservoirs of phase change material. In other words, neither the frame nor the additional reservoirs of phase change material contact the insulated casing in arrangement 1.
[0086] Arrangement A differs from arrangement 1 in that there is no frame present. This arrangement includes a first reservoir of phase change material. There is no reservoir of phase change material in contact with the product drawer in arrangement A.
[0087] Each of the arrangements in this example included a plastic (PVC) product drawer for holding the frozen confectionery items. In arrangement 1 the product drawer was slidably received within the frame, whereas in arrangement A the product drawer rests on two thin strips of polystyrene placed on the base of the insulated container. This ensures that there is an air gap between the insulated housing and the drawer.
[0088] The arrangements were tested side by side at room temperature (20° C.). Each one was loaded with 30 frozen confectionery items (Magnum classic minis, 50 g) and then sealed and monitored for 24 hours with temperature measurements being taken throughout the monitoring period.
[0089] The average temperature measurements of the three arrangements are shown in FIG. 6. Arrangement 1 (PVC frame) took 4.5 hours longer to reach −18° C. than arrangement A, and 13.3 hours longer to reach −15° C. Similarly, arrangement 1 (AI frame) took 5.6 hours longer to reach −18° C. than arrangement A, and 17 hours longer to reach −15° C. Therefore, arrangement 1 (with a PVC frame) provided temperature stability between −18° C. and −15° C. for 10 hours, whilst the same arrangement with an aluminium frame provided temperature stability between −18° C. and −15° C. for 12.5 hours.
Example 2
[0090] The properties of three thermally insulated container arrangements were investigated. In each arrangement, the frame is a four-sided aluminium frame mounted such that there is an air gap of 2 to 3 mm around all sides of the frame and there is an aluminium product drawer in the upper portion of the frame (i.e. supported by projections from the sidewalls).
[0091] Arrangement 2 is illustrated in FIG. 2a and includes a second reservoir of phase change material (containing 1.3 kg of E-19 from PCM Products Ltd; phase change temperature −18.7° C.). The second reservoir of phase change material is placed inside the frame and is in contact with lower wall of the frame.
[0092] Arrangement 3 is illustrated in FIG. 2b and includes dry ice (0.6 kg) which is placed on top of the first reservoir of phase change material. The dry ice does not touch the insulated outer housing.
[0093] Arrangement 4 is illustrated in FIG. 2c and includes both dry ice (0.6 kg) and a second reservoir of phase change material (containing 1.3 kg of E-19 from PCM Products Ltd; phase change temperature −18.7° C.). The dry ice is placed on top of the first reservoir of phase change material and does not touch the insulated outer housing. The second reservoir of phase change material is placed inside the frame and is in contact with lower wall of the frame.
[0094] Before being used in the arrangements of this example, each reservoir of phase change material was cooled so that all of the phase change material was solid (i.e. >24 hours in a freezer operating at −32° C.).
[0095] The arrangements were tested side by side at room temperature (20° C.). Each one was loaded with 60 frozen confectionery items (Magnum classic minis, 50 g)—30 of which were placed in the product drawer and 30 of which were placed in the lower portion of the frame. The arrangements were sealed and monitored for 21 hours with temperature measurements being taken throughout the monitoring period.
[0096] The average temperature measurements of the three arrangements are shown in FIG. 7. It can be seen that arrangement 2 (with a first and second reservoir of phase change material) has a stable temperature profile between 4 and 13 hours. This represents a window in which the frozen confectionery items can be served and be at a suitable temperature for immediate consumption. The temperature profile of arrangement 3 (with a first reservoir of phase change material and dry ice) indicates that it is possible to increase the initial storage period (i.e. at a temperature below −18° C.) to around 5 hours. After this period, the frozen confectionery items will be at a temperature where they can be served for immediate consumption. However, once this temperature is reached, the window during which the frozen confectionery products can be served is narrower than it is for arrangement 2. Finally, it can be seen that arrangement 4 (with a first and second reservoir of phase change material and dry ice) has both the increased initial storage period (i.e. at a temperature below −18° C.) of around 5 hours, and a stable temperature profile between around 7 and 16 hours. This represents a window in which the frozen confectionery items can be served and be at a suitable temperature for immediate consumption.
[0097] In conclusion, the use of two reservoirs of phase change material increases the length of the window in which the frozen confectionery products can be served and be at a suitable temperature for immediate consumption. The use of dry ice increases the initial storage period (i.e. the period in which the frozen confectionery items are too cold to be suitable for immediate consumption). This may be useful, since there will inevitably be a period during which the frozen confectionery items are stored whilst being transported to the plane, and in any case, service of such items will not begin until the aircraft is airborne.
