WO2014019625A1

WO2014019625A1 - Refrigerated sales cabinet

Info

Publication number: WO2014019625A1
Application number: PCT/EP2012/065167
Authority: WO
Inventors: Oliver Stakelbeck
Original assignee: Carrier Corporation
Priority date: 2012-08-02
Filing date: 2012-08-02
Publication date: 2014-02-06
Also published as: EP2879553B1; CN104717907A; CN104717907B; EP2879553A1

Abstract

A refrigerated sales cabinet (20) comprises a cabinet body (22) providing a refrigerated sales space for supporting refrigerated goods to be sold, a door frame (21) having a top post (34), a bottom post (36) and at least two upright posts (32), and at least one door (14). At least one of the posts (32, 34, 36) comprises a cold main body (4) and an insulating front element (9) comprising, from back to front, a rear panel (10), which is attached to the cold main body (4), and a front panel (11) forming the front surface of the post (32, 34, 36). At least one surface of the front panel (11) is covered with a coating (11 a) employing nano-technology for providing thermal insulation against the cold main body (4) of the post (9).

Description

Refrigerated Sales Cabinet The present invention relates to a refrigerated sales cabinet.

A refrigerated sales cabinet as it is known in the art comprises a cabinet body, side panels, a door frame and at least one door, wherein the side panels are installed on the sides of the cabinet body, the door frame is installed on the cabinet body, the door is installed on the door frame, and sealing strips are provided between the cabinet door and the door frame.

The front surface of the door frame, which is exposed to ambient conditions, is cooled when the refrigerated sales cabinet is operated. If the temperature of the front surface drops below the dew point, humid ambient air condensates at this front surface causing water droplets to appear, which is uncomfortable for the customers. Therefore, there is a need to prevent the temperature of this surface to fall below the dew point temperature.

A door frame according to the prior art comprises an electrical heating element, which serves to keep the temperature of the front surface above the dew point in order to prevent the condensation of water on the door frame. The electrical energy consumed by such an electrical heating element is very high and considerably contributes to the total energy consumed by the refrigerated sales cabinet in operation.

It therefore would be beneficial to reliably avoid condensation at the front surface of a door frame of a refrigerated sales cabinet, whereas at the same time the electrical energy consumption is minimized.

A refrigerated sales cabinet according to an embodiment of the invention comprises a cabinet body providing a refrigerated sales space for supporting refrigerated goods to be sold therein; a door frame having a top post, a bottom post, and at least two upright posts; and at least one door. At least one of the posts has a main body providing a structural frame member, which is cooled to low temperatures when the refrigerated sales cabinet is operated as it is exposed to the cooled goods presentation space, and an insulating front element. Said insulating front element comprises, from back to front, a rear panel attached to the cold main body and a front panel forming the front surface of the post. At least a front side of the insulating front element is covered with a coating which is based on nano- technology and provides thermal insulation against the cold main body of the post in order to reduce or even avoid the condensation of humid air at the front surface of the front panel.

A method of thermally insulating a refrigerated sales cabinet according to an exemplary embodiment of the invention which comprises a cabinet body providing a refrigerated sales space for supporting refrigerated goods to be sold therein; a door frame having a top post, a bottom post, and at least two upright posts, wherein each of the posts comprises a cold main body; and at least one door includes the steps of: coating at least one side of a front panel with a thermally insulating coating employing nano-technology; forming a front element comprising, from back to front, a rear panel and the front panel; and attaching the front element to the cold main body of a respective one of the posts, so that the coated side of the front panel forms the front surface of the post providing thermal insulation against the cold main body of the post. The disclosure of the invention will become more easily understood with reference to the accompanying drawings. It is appreciated by those skilled in the art that the accompanying drawings are exemplary only and are not intended to limit the scope of protection of the invention. In the drawings: Figure 1 shows an exploded view of a refrigerated sales cabinet of the front-access type with doors and a door frame according to an embodiment of the invention.

Figure 2 shows a horizontal cross section through one of the upright posts of the door frame and part of adjacent doors.

Figures 1 and 2 and the following discussion describe particular embodiments of the invention so as to teach those skilled in the art how to produce and use the best modes of the invention. In order to teach the principle of the invention, several conventional aspects have been simplified or omitted. Those skilled in the art should understand that variations originating from these embodiments also fall within the scope of the invention. Those skilled in the art should understand that the features to be described below can be combined in various ways so as to form numerous variations of the invention. Therefore, the invention is not limited to the following particular embodiments and is merely defined by the appended claims and their equivalents.

A refrigerated sales cabinet 20 of the front-access type with doors 14 and a door frame 21 according to an exemplary embodiment of the invention is shown in Figure 1 . The refrigerated sales cabinet 20 as shown in Figure 1 comprises a cabinet body 22, a left side panel 30, a right side panel 31 , a door frame 21 and a plurality of doors 14, The cabinet body 22 comprises a bottom part 26, a roof plate 24, a rear wall 27 and a plurality of shelves 28 arranged in between.

A complete refrigeration circuit comprising a compressor, a condenser, an expansion device and an evaporator may be installed in the cabinet body 22, in order to provide a standalone refrigerated cabinet which only needs to be connected to an electric power sup- ply for operation.

Alternatively, only one or more evaporators may be installed within the cabinet body 22, the evaporators being configured to be fluidly connected to an external refrigeration circuit provided in the building in which the refrigerated sales cabinet is to be installed.

The refrigerated sales cabinet 20 may be a cooling sales cabinet 20 which is configured to cool the goods presentation space to cooling temperatures above 0°C.

Alternatively, the refrigerated sales cabinet 20 may be a freezing sales cabinet 20, which is configured to cool the goods presentation space to freezing temperatures below 0 °C, in particular to temperatures below -1 5 °C in order to store and present frozen goods to potential customers.

The left side panel 30 and the right side panel 31 are respectively installed on the left and right hand side of the cabinet body 22. The door frame 21 , which comprises a plurality of vertical extending upright posts 32, a horizontal top post 34 and a horizontal bottom post 36, respectively connecting the upright posts 32 to each other, is installed on a front side of the cabinet body 22. A plurality of cabinet doors 14 is installed on the front side of the door frame 21. The cabinet body 22, the left side panel 30, the right side panel 31 , the door frame 21 and the cabinet doors 14 are installed together to form a refrigerated goods storage and presentations space which is closed by and accessible through the doors 14. Figure 2 shows a horizontal cross section through one of the upright posts 32 of the door frame 21 and portions of two adjacent doors 14. The doors 14 are for example insulated glass doors 14 respectively comprising two glass panels 1 6 which are separated by an intermediate vacuum layer 1 6a. The glass panels 16 are supported by an outer main body 1 5, which may be an extruded element made of plastic or metal, for example aluminium.

In accordance with an embodiment of the invention each upright post 32 includes a rigid main body 4, which may be made of aluminium or another high strength material and which is cooled to low temperatures when the refrigerated sales cabinet 20 is operated as it is exposed to the cooled goods presentation space. The cross section of the main body 4 is basically C-shaped, when looked at in the cross-section, comprising a rear portion 4a and two side portions 4b. The side portions 4b are arranged basically parallel to each other and perpendicular to the rear portion 4a. An internal support member 6 is arranged within the main body 4 extending basically parallel to the rear portion 4a and providing an elongated first hollow space 5 within the main body 4, the first hollow space 5 being defined by the internal support member 6, the rear portion 4a and the two side portions 4b. Optionally, the first hollow space 5 may be filled with an insulating material, e.g. a thermally insulating foam, in order to enhance the thermally insulating properties of the upright post 32.

A front side of the internal support member 6 facing the doors 14 is provided with two first bracket members 8 extending opposite to each other in a plane extending basically parallel to the plane of the doors 14 when they are arranged in the closed position parallel to the door frame 21 . An insulating front element 9 is mounted to the internal support member 6 by means of corresponding second bracket members 1 3 provided at the rear side of the rear panel 10 engaging with the first bracket members 8 provided at the internal support mem- ber 6. The mutual engagement of the bracket members 8, 13 allows a convenient and secure installation of the insulating front element 9 within the main body 4 of the upright post 32.

The insulating front element 9 includes a rear panel 10 facing the internal support member 6 and comprising the corresponding second bracket members 13. The rear panel 10 is basically planar comprising side wall strips 10b so as to have a C-shape when looked at in the cross-section and extends basically parallel to the rear portion 4a of the main body 4 spanning the distance between the two side portions 4b and thereby providing two further elongated hollow spaces 7, which are respectively defined by the rear panel 1 0 of the insulating front element 9, one of the side portions 4b of the main body 4 and the internal support member 6. The insulating front element 9 further comprises a basically planar front panel 1 1 , which is arranged facing the doors 14 opposite to the rear panel 10 on the front side of the insulating front element 9. At least the front side of the planar front panel 1 1 facing the doors 14 is covered with a coating 1 1 a which employs nano-technology providing excellent ther- mally insulating properties in order to enhance the thermal insulation properties provided by the insulating front element 9.

The thermally insulating coating 1 l a enhances the thermal insulating properties of the insulating front element 9 considerably. As the coating 1 l a, which applies nano-technology and has a very low thermal conductivity of e.g. less than 0,02 W/mK, provides a very efficient thermally insulating coating 1 1 a, a thin coating 1 1 a, which does not considerably add to the thickness of the front panel 1 1 and which may e.g. be applied by spraying, may be sufficient in order to reliably prevent the condensation of ambient air on the front side of the refrigerating sales cabinet 20 without employing an electrical heating. The thermally insulating coating I l a can be a clear, nano-technology-based insulation and mole prevention coating used to insulate. It can be non-hazardous and water-based.

An example for a suitable nano-technology based material is for example provided by "Nansulate"®, which is commercially available.

Optionally at least a portion of the rear panel 1 0, in particular the back-side of the rear panel 10 averted from the doors 14, may be covered with an thermally insulating coating 10a employing nano-technology, as well, in order to reduce the transfer of energy through the front element 9 even further.

Additionally or alternatively a thermally insulating layer 12 may be provided on the front side of the C-shaped rear panel 10 of the insulating front element 9 facing the doors 14. The thermally insulating layer 12 may be enclosed within the insulating front element 9 in between the rear panel 10 and the front panel 1 1 . Such an enclosure within the insulating front element 9 protects the thermally insulating layer 12 from being damaged, e.g. by the doors 14 or clumsy customers hitting the upright post 32, and further allows an easy installation of the thermally insulating layer 12 at the main body 4 of the upright post 32.

The thermally insulating layer 12 may include a thermally insulating foam and/or a vacu- um panel providing thermal insulation. The first and second panels 10, 1 1 of the insulating front element 9 may be made of any suitable plastic or metallic material, e.g. Aluminium or PVC, or a combination thereof.

Sealing elements 18, which may be made of an elastic material such as rubber, are mount- ed to front panel 1 1 of the insulating front element 9 about the periphery of the door openings for defining a sealing and stop surface for the doors 14 in order to provide an air seal between the doors 14 and the upright post 32 of the door frame 21 , when the doors 14 are in their respective closed positions. Alternatively or additionally sealing elements 1 8 may be mounted to the doors 14. The sealing elements 18 are configured to prevent the ex- change of cool air from the refrigerated goods storage and presentation space of the refrigerated sales cabinet 20 with warm ambient air.

A magnet 19 may be provided in, on or below the sealing element 18 in order to attract the metallic outer frame member 15 locking the door 14 securely in the closed position in or- der to avoid an undesired opening of the door 14. If the outer frame member 15 is made of plastic or a non magnetic metal, a further magnet 1 7 or an element 17 comprising a magnetic metal may be provided in or on the outer frame member 1 5 in order to be attracted by the magnet 19 provided in on or below the sealing element 1 8. Alternatively or additionally a mechanical lock, which is not shown in the figures, may be provided in order to securely lock the doors 14.

An exemplary embodiment of the invention has been described with reference to an upright post 32 of the door frame 21 . The skilled person, however, will easily understand that the idea of the invention may be analogously applied to the top and bottom posts 34, 36, which extend horizontally between the upright posts 32, as well, in order to avoid the generation of condensation water on the complete front surface of the door frame 21 .

In a refrigerated sales cabinet according to an embodiment of the invention a thermally insulating coating is provided at the front surface of a front panel of at least one of the posts of the refrigerated sales cabinet in order to minimize the heat transfer through the post and to keep the front surface temperature above the dew point. In particular, a coating employing nano-technology providing exceptional thermal insulation properties is used as an thermal insulation material. Due to the exceptional thermal insulation properties of the coating, which is based on nano-technology, it is not necessary to heat the post in order to avoid condensation of ambient air. The inventors have discovered that instead of heating the posts of the door frame of a refrigerated sales cabinet, an insulating front element as defined in the claims and as described herein can be provided, which is - contrary that what was believed until the present invention was made - capable to reliably avoid condensation at the front surface of such posts. Until the point in time when the present invention was made, there was no insulating front element known or available which could reliably avoid condensation at the front surface of such posts while being subject to constant cooling from the back of the refrigerated sales cabinet. None of the available insulating techniques was able to provide a sufficient insulation at that particular position that could reliably avoid condensation over time.

A thermally insulating coating employing nano-technology can be a clear, nano- technology-based insulation and mold prevention coating used to insulate. Such nano- coating is known for having a surface structure onto which the amount of particles, particularly dirt particles, which adhere thereto is significantly reduced. However, the inventors have discovered that such nano-coating also has excellent thermal insulation properties and that therefore a front panel the front surface of which being covered with such thermally insulating coating employing nano-technology will provide an excellent thermal insulation against the cold main body of the post. An example of a suitable thermally insulating coating employing nano-technology is formed by the product Home Protect Clear Coat of the company Nansulate.

In an embodiment at least a portion of the rear panel is covered with an insulating coating employing nano-technology, in order to enhance the thermally insulating properties of the insulating front element even further.

In an embodiment the nano-technology based material used for the coating has a thermal conductivity of less than 0,02 W/m . Such a material provides a very efficient thermal insulation even if it is applied in the form of a thin coating.

In an embodiment a thermally insulating layer is arranged between the rear panel and the front panel in order to provide additional thermal insulation. Said thermally insulating layer may comprise a thermally insulating foam and/or a vacuum panel. In an embodiment the thermally insulating layer is sandwiched between said rear panel and said front panel. Said rear panel and said front panel together with two respective side wall strips may completely enclose said thermally insulating layer. Such a configuration, in which the thermally insulating layer is completely enclosed, securely fixes the thermally insulating material and protects it from being damaged. It further allows an easy and convenient installation of the thermally insulating material. In an embodiment the rear panel and/or the front panel comprise a plastic material, particularly PVC. A plastic material, such as PVC, provides a cheap lightweight material with good thermal insulating properties.

In an embodiment the insulating front element is attached to the cold main body of the post by means of a snap-on connection, particularly by a fastening bracket provided at the rear side of the rear panel that engages with a corresponding fastening bracket provided at the cold main body. A snap-on connection allows to easily install and deinstall the front element to and from the post, respectively. Optionally the fastening bracket may be provided in the form of a rail extending along the length of the post. Such a rail may be produced by extrusion and provides a secure fixture over the whole length of the post.

In an embodiment the door is formed as a pivotable door, which is pivotable between a closed position and at least one open position, said pivotable door having a first side portion connected with a hinge and a pivotable second side portion opposite to the first side portion. In the closed position the door rests with the rear side of its second side portion against one of the upright posts, and with the rear sides of its upper and lower portions against the top and bottom posts, respectively. A pivotable door in its closed position iso- lates the refrigerated sales space from the environment in order to avoid cold air from flowing out of the refrigerated sales space thereby reducing the energy needed for cooling the refrigerated sales space. In its open position a pivotable door allows an easy and convenient access to the refrigerated sales space and the goods stored and presented therein. In an embodiment the rear sides of the second side portion, of the upper portion and/or of the lower portion of the door, that, in the closed position of the door, respectively rest against the upright, top and/or bottom posts, are respectively provided with sealing elements, and/or the front sides of the upright, top and/or bottom posts are respectively provided with sealing elements. Sealing elements provided between the door and the posts enhance the insulating properties of the door in the closes position. The front surface of the upright post may provide a stop for the door in order to define the closed position of the door.

In an embodiment the second side portion of a door and the associated upright post, partic- ularly a sealing element provided at the associated upright post, comprise a pair of two magnets or a combination of a magnet and an element of magnetic material, in order to hold the door in the closed position. Such an arrangement of at least two magnets and/or a magnet and an element of magnetic material reliably prevents the door from being accidentally opened or not completely closed, which would allow cold air to flow out of the refrigerated sales space increasing the energy needed for cooling the refrigerated sales space.

In an embodiment at least one pair of two doors with mirror-inverted pivoting directions is provided, one door besides the other, wherein the pivotable second end portions of both doors are facing each other, such that both doors, in the closed position, rest with the rear sides of their second side portions against the same upright post. Such an arrangement of adjacent doors allows a convenient access to the goods stored within the refrigerated sales space. In an embodiment the doors respectively comprise at least one pane of glass, allowing to look into the refrigerated sales space without opening at least one of the doors.

In an embodiment the refrigerated sales cabinet is configured to cool the refrigerated sales space down to freezing temperatures below 0 °C, in particular to temperatures below -15 °C. This allows to store and present frozen goods to potential customers. Good thermal insulation properties of the insulating front element are in particular important at such low temperatures in order to reduce condensation at the front surface of the refrigerated sales cabinet. The refrigerated sales cabinet may be a standalone refrigerated cabinet comprising a complete refrigeration circuit which needs to be connected only to an electric power supply for operation. Alternatively the refrigerated sales cabinet may comprise only at least one evaporator to be fluidly connected to an external refrigeration circuit which is installed in the building in which the refrigerated sales cabinet is placed.

In an embodiment the coating using nano-technology is sprayed onto the front panel. Spraying provides a convenient method of applying the nano-technology based material to the front panel. Spraying in particular allows to form a homogeneous coating having a uniform thickness.

While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention is not l imited to the particular embodiment disclosed, but that the invention wi ll include all embodiments falling within the scope of the appended claims.

List of Reference Numerals

4 cold main body of a post

4a rear portion of a post

4b side portions of a post

5 first hollow space

6 support member

7 second hollow space

8 first fastening bracket

9 insulating front element

10 rear panel

10a thermally insulating coating

10b side wall strip

1 1 front panel

1 1 a thermally insulating coating

12 layer of insulating material

13 second fastening bracket

14 door

15 outer frame member

16 door panel

16a vacuum layer

17 magnet or element comprising magnetic metal

18 sealing strip

19 magnet

20 refrigerating sales cabinet

22 cabinet body

21 door frame

24 roof plate

26 bottom part

27 rear wal 1

28 shelves

30 left side panel

31 right side panel

32 upright post

34 top post

36 bottom post

Claims

Claims 1. Refrigerated sales cabinet (20), comprising:

a cabinet body (22) providing a refrigerated sales space for supporting refrigerated goods to be sold therein;

a door frame (21 ) having a top post (34), a bottom post (36), and at least two upright posts (32);

at least one door ( 14);

wherein at least one of the posts (32, 34, 36) has a cold main body (4) and an insulating front element (9), said insulating front element (9) comprising, from back to front, a rear panel (10), which is attached to the cold main body (4), and a front panel (1 1 ) forming the front surface of the post (32, 34, 36),

wherein at least a front surface of the front panel (1 1 ) is covered with a thermally insulating coating (1 1 a) employing nano-technology for providing thermal insulation against the cold main body (4) of the post (9).

2. Refrigerated sales cabinet (20) of claim 1 , wherein at least a portion of the rear panel (10) is covered with an insulating coating ( 10a) employing nano-technology.

3. Refrigerated sales cabinet (20) of claim 1 or 2, wherein the nano-technology based insulating coating (10a, 1 1 a) has a thermal conductivity of less than 0,02 W/mK.

4. Refrigerated sales cabinet (20) of any of the preceding claims, wherein a thermally insulating layer (12) is arranged between said rear panel (10) and said front panel (1 1).

5. Refrigerated sales cabinet (20) of claim 4, wherein said thermally insulating layer (12) comprises a thermally insulating foam and/or a vacuum panel.

6. Refrigerated sales cabinet (20) of claim 4 or 5, wherein said thermally insulating layer (12) is sandwiched between said rear panel ( 10) and said front panel (1 1 ), and/or wherein said rear panel (1 0) and said front panel (1 1 ) together with two respective side wall strips (10b) completely enclose said thermally insulating layer (12).

7. Refrigerated sales cabinet (20) of any of the preceding claims, wherein the rear panel (10) and/or the front panel (1 1 ) comprise a plastic material, particularly PVC.

8. Refrigerated sales cabinet (20) of any of the preceding claims, wherein the insulating front element (9) is attached to the cold main body (4) of the post (32, 34, 36) by means of a snap-on connection (8, 13), particularly by a second fastening bracket (13) provided at the rear side of the rear panel (10) that engages with a corresponding first fastening bracket (8) provided at the cold main body (4).

9. Refrigerated sales cabinet (20) of any of the preceding claims, wherein the door (14) is formed as a pivotable door (14) being pivotable between a closed position and at least one open position, said pivotable door (14) having a first side portion connected with a hinge and a pivotable second side portion opposite to the first side portion; and/or wherein the door (14), in the closed position, rests with the rear side of its second side portion against one of the upright posts (32), and with the rear sides of its upper and lower portions against the top and bottom posts (34, 36), respectively.

10. Refrigerated sales cabinet (20) of claim 9, wherein the rear sides of the second side portion, of the upper portion and/or of the lower portion of the door (14) that respectively rest against the upright, top and/or bottom posts (32, 34, 36), when the door (14) is in its closed position, are provided with at least one sealing element (1 8), and/or wherein the front sides of the upright, top and/or bottom posts (32, 34, 36) are respectively provided with at least one sealing element (1 8).

1 1. Refrigerated sales cabinet (20) of claim 9 or 10, wherein the second side portion of the door (14) and the associated upright post (32), particularly a sealing element (18) provided at the associated upright post (32), comprise a pair of two magnets (17, 19) or a combination of a magnet ( 19) and an element (1 7) comprising a magnetic material, in order to hold the door (14) in the closed position.

12. Refrigerated sales cabinet (20) of any of claims 9 to 1 1 , wherein at least one pair of two doors (14) is provided, each pair of two doors (14) having a first door and a second door positioned besides the first door, the first and the second doors having mirror-inverted pivoting directions, wherein the pivotable second end portions of the first and second doors (14) are facing each other, such that, in the closed position, the first and second doors (14) rest with the rear sides of their second side portions against the same upright post (32).

13. Refrigerated sales cabinet (20) of any of the preceding claims, wherein the refrigerated sales cabinet (20) is configured to cool the refrigerated sales space down to freezing temperatures below 0 °C, in particular to temperatures below - 1 5 °C.

5 14. Method of thermally insulating a refrigerated sales cabinet (20) comprising:

a door frame (21 ) having a top post (34), a bottom post (36), and at least two upright posts (32), each of the posts (32, 34, 36) comprising a cold main body (4);

o at least one door (14);

wherein the method comprises the steps of:

coating at least one side of a front panel ( l l ) with a thermally insulating coating (1 la) employing nano-technology;

forming a front element (9) comprising, from back to front, a rear panel (10) and the5 front panel (1 1 );

attaching the front element (9) to the cold main body (4) of a respective one of the posts (32, 34, 36), so that the coated side of the front panel (1 1 ) forms the front surface of the post (32, 34, 36) providing thermal insulation against the cold main body (4) of the post (32, 34, 36).

0

15. Method of claim 14, wherein the thermally insulating coating (1 l a) is sprayed onto the at least one front surface element (10).