WO2009039874A1

WO2009039874A1 - Refrigerating sales furniture

Info

Publication number: WO2009039874A1
Application number: PCT/EP2007/008486
Authority: WO
Inventors: Gabriele Klippel; Oliver Stakelbeck
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 2007-09-28
Filing date: 2007-09-28
Publication date: 2009-04-02
Anticipated expiration: 2010-03-28
Also published as: EP2194819B1; EP2194819A1

Abstract

A refrigerating sales furniture comprises a furniture body (4) having a goods presentation and refrigeration space (6), a heat-rejection heat exchanger (18) of a vapor compression cycle, said heat-rejection heat exchanger (18) being positioned within the furniture body (4) and cooling, in operation, refrigerant flowing therethrough against ambient air, and at least one air inlet (16) leading an ambient air flow to the surface of the heat-rejection heat exchanger (18). Said air inlet (16) is arranged at a greater height than the height of the middle portion of the heat-rejection heat exchanger (18), thereby limiting, in operation, the amount of ambient air comprising soiling particles flowing through the heat-rejection heat exchanger (18).

Description

REFRIGERATING SALES FURNITURE

The present invention is related to a refrigerating sales furniture.

Refrigerating sales furnitures comprising a heat-rejection heat exchanger as part of a vapor compression cycle use an ambient airflow for cooling the refrigerant flowing through the heat-rejection heat exchanger. Refrigerating sales fur- nitures as they are known in the state of the art comprise an air inlet at the bottom of the furniture in order to lead ambient air to the surface of the heat-rejection heat exchanger. In practice such heat-rejection heat exchangers get soiled quickly, and such soiled heat-rejection heat exchangers can only provide part of their normal heat-rejection capacity. This can cause overheating of the refriger- ant and the oil dissolved therein, which can result in damaging of the compressor of the vapor compression cycle. Thus, frequent maintenance for cleaning the heat-rejection heat exchanger is needed, which results in high cost for operating the refrigerating sales furniture.

Accordingly, it would be beneficial to provide a more efficient refrigerating sales furniture which needs cleaning and maintenance less frequently.

Exemplary embodiments of the invention include a refrigerating sales furniture comprising a furniture body having a goods presentation and refrigeration space and a heat-rejection heat exchanger as part of a vapor compression cycle. Said heat-rejection heat exchanger is positioned within the furniture body and cooling, in operation, refrigerant flowing therethrough against ambient air. The refrigerating sales furniture further comprises at least one air inlet leading an ambient air flow to the surface of the heat-rejection heat exchanger. Said air inlet is arranged at a greater height than the height of the middle portion of the heat-rejection heat exchanger, thereby limiting, in operation, the amount of ambient air comprising soiling particles flowing through the heat-rejection heat exchanger. Exemplary embodiments also include a method for operating a refrigerating sales furniture, the refrigerating sales furniture comprising a heat-rejection heat exchanger as part of a vapor compression cycle and a furniture body having a goods presentation and refrigeration space. Said heat-rejection heat exchanger is positioned within the furniture body and cooling, in operation, refrigerant flowing therethrough against ambient air. The furniture further comprises at least one air inlet arranged at a greater height than the height of the middle portion of the heat-rejection heat exchanger. An ambient air flow it lead to the surface of the heat-rejection heat exchanger through said at least one air inlet thereby limiting, in operation, the amount of ambient air comprising soiling particles flowing through the heat-rejection heat exchanger.

Embodiments of the invention will be described in greater detail below with reference to the enclosed Figures, wherein

Figure 1 shows a perspective front view of a refrigerating sales furniture according to an embodiment of the invention, and

Figure 2 shows a sectional side view of the refrigerating sales furniture of Fig. 1.

Figure 1 shows a perspective front view of a refrigerating sales furniture 2.

The refrigerating sales furniture 2 rests on a base 14 which is arranged at the bottom of the furniture 2. A rear wall (not shown) extending vertically upwards is arranged at the back of the base 14. The left and right sides of the refrigerating sales furniture 2 are formed by upright left and right side members 10. The upper sides of the left and right side members 10 are slanted backwardly from a bend 30 to the joining position with the rear wall. A top 9 is arranged between upper ends of the left and right side members 10 in a rear portion thereof.

The left and right side members 10 are thermally isolating. On top of the base 14 and in between said left and right side members 10 a compartment 11 is formed. The compartment 11 is defined by the rear wall, the side members 10, an upright front wall 12 and a cover 15 at the top. A heat-rejection heat ex- changer (not shown) forming part of a vapor compression cycle is arranged in- side the compartment 11. The compartment 11 may also house further parts of a vapor compression cycle as e.g. a compressor. A number of air inlets 16 are formed as holes in the upper part of the front wall 12. Said air inlets 16 lead ambient air from outside the furniture 2 to the heat-rejection heat exchanger inside the compartment 11.

In the embodiment shown in Figure 1 the air inlets 16 are arranged in a horizontal straight line, however, the air inlets 16 may also be arranged in two or more rows or in another pattern in the upper part of the front wall 12. No air inlets 16 must be formed in the lower part of the front wall 12 in order to avoid that soiled air from the area close to the floor is led into the compartment 11.

A goods presentation and refrigeration space 6 is formed in between the side members 10 on top of the compartment 11. A couple of goods display decks 8 are arranged horizontally at different heights in said goods presentation and refrigeration space 6 in order to support the goods to be presented.

At least one cooling element (not shown) such as an evaporator of a vapor compression cycle can be arranged within the goods presentation and refriger- ation space 6, for example below the goods display decks 8, at the back or at the side members 10. Alternatively or additionally, air outlets (not shown) may be formed in the side members 10, in the back or tin he top of the goods presentation and refrigeration space 6 in order to deliver cool air into the goods presentation and refrigeration space 6.

In the embodiment shown in Figure 1 the front side of the goods presentation and refrigeration space 6 is open so that potential customers can reach directly into the goods presentation and refrigeration space 6. Cool air dropping out of the goods presentation and refrigeration space 6 to the front will at least partial- Iy enter through the air inlets 16 into the compartment 11 and flow to the heat- rejection heat exchanger (not shown). Utilizing such cooled air for supply to the heat-rejection heat exchanger will increase the efficiency of the vapor compression cycle. In an alternative embodiment the refrigerating sales furniture 2 may comprise a shutting means (not shown) as e.g. a door or a blind for closing the front of the goods presentation and refrigeration space 6. This will prevent cooled air from dropping out of the goods presentation and refrigeration space 6 so that less energy will be needed for cooling the goods presentation and refrigeration space 6.

Figure 2 shows a sectional side view of the refrigerating sales furniture 2.

Like elements are designated by means of like reference signs, and they will not be discussed in detail again.

A heat-rejection heat exchanger 18 and a fan 22 for sucking an ambient air flow over the surface of the heat-rejection heat exchanger 18 are arranged inside the compartment 11. In the embodiment shown in Figure 2 the fan 22 is arranged behind the heat-rejection heat exchanger 18 in order to suck ambient air from the outside through the air inlets 16 formed in the upper part of the front wall 12 over the surface of the heat-rejection heat exchanger 18. However, in an alternative embodiment the fan 22 may be arranged in front of the heat-rejection exchanger 18, i.e. in between the heat-rejection heat exchanger 18 and the front wall 12 in order to suck in ambient air from the outside and to blow it over the surface of the heat-rejection heat exchanger 18. In a further embodiment, a first fan 22 may be arranged in front of the heat-rejection heat exchanger 18 and a second fan may be arranged behind the heat-rejection heat exchanger 18.

The ambient air sucked in by the fan 22 and having passed the heat-rejection heat exchanger 18 exits the compartment 11 through at least one air outlet 26 formed in the rear wall 24 of the refrigerating sales furniture 2. The heat-rejec- tion heat exchanger 18 is fluidly connected to the other components of the vapor compression cycle which are not shown, especially the compressor and the expansion device. The front wall 12 may be formed as a removable front panel and it can be attached to the base 14, the side members 10 or the cover 15. This allows easy access to the interior of the compartment 11 by removing the panel. The air inlet 16 formed in the front wall 12 of the compartment 11 is arranged at a height above the height of the middle portion of the heat-rejection heat exchanger 18, thereby limiting, in operation, the amount of ambient air from the bottom comprising soiling particles flowing through the heat-rejection heat exchanger 18. In the embodiment shown in Figure 2 the exemplary air inlet 16 is formed as a horizontal hole or channel in the front wall 12. However, the air inlet 16 may also be formed as an inclined channel or as a tube comprising bends which are arranged so that the outer opening of the channel or tube is posi- tioned at a greater height than its inner opening. This allows to arrange the outer opening of the air inlet 16 at an even greater height thereby even further limiting the amount of soiling particles from the floor sucked in together with the ambient air and flowing through the heat-rejection heat exchanger 18.

The surface of the heat-rejection heat exchanger 18 comprises a non-stick coating, in particular a non-stick coating comprising nano particles. Thus the amount of soiling particles that stick or collect on the surface of the heat-rejection heat exchanger 18 can be significantly reduced.

In particular, the non-stick coating can comprise nano cutting grains or edges, that cut long fibers contained in the ambient air flow and thus prevent these long fibers from depositing onto the surface or in air channels of the heat-rejection heat exchanger 18.

On top of the compartment 11 the goods presentation and refrigeration space 6 is arranged. The goods presentation and refrigeration space 6 is thermally isolated by a horizontal, thermally isolated bottom integrally formed with the cover 15 of the compartment 11, by a vertical, thermally isolated back wall 17 of the goods presentation and refrigeration space 6, by a horizontal, thermally isolat- ed ceiling 7 extending over the rear portion of the goods presentation and refrigeration space 6, and by the vertical, thermally isolated side members 10.

Several goods display decks 8 are arranged on top of each other in front of the back wall 17, they are distributed over the height of the goods presentation and refrigeration space 6 at equal distances, and they extend horizontally from the back wall 17 to the front of the furniture 2.

In a refrigerating sales furniture according to the exemplary embodiments of the invention, as described above, the air inlet is arranged at a greater height than the height of the middle portion of the heat-rejection heat exchanger. Thus, only ambient air from above the floor of the room in which the furniture is installed is led to the heat-rejection heat exchanger, wherein only a considerably reduced amount of ambient air lying on the floor or close to the floor is led to the surface of the heat-rejection heat exchanger. As the air lying on the floor or close to the floor normally comprises a plurality of soiling particles such as dust and fibers and these particles are often sticky and greasy, the soiling of the heat-rejection heat exchanger is reduced significantly. Thus, maintenance and cleaning works of the heat-rejection heat exchanger have to carried out less fre- quently and the costs for operating the refrigerating sales furniture are considerably reduced.

In a refrigerating sales furniture according to the exemplary embodiments of the invention, as described above, can be a refrigerating sales furniture operat- ing at refrigerating temperatures of above 0⁰C or a refrigerating sales furniture operating at freezing temperatures of below 0⁰C.

In an embodiment of the invention the air inlet is arranged at the front of the furniture. Since the area in front of a refrigerating sales furniture is usually cleaner than the area in the back of such a furniture as it is difficult to clean the area behind the furniture when the furniture is set up in front of a wall, this reduces the soiling of the heat-rejection heat exchanger even further.

In a further embodiment the goods presentation and refrigeration space is open to the front. This allows potential customers to directly reach into the goods presentation and refrigeration space. If in this embodiment the air inlets are arranged at the front of the furniture cool air dropping out to the front of the goods presentation and refrigeration space is sucked into the compartment and led by the surface of the heat-rejection heat exchanger for enhancing the effi- ciency of the heat-rejection heat exchanger. In a further embodiment at least part of the surface of the heat-rejection heat exchanger comprises a non-stick coating. This additionally reduces soiling of the surface of the heat-rejection heat exchanger, since it reduces the sticking of soiling particles onto said surface. In a further embodiment the non-stick coating is a varnish which can be applied to the surface very conveniently.

In a further embodiment at least part of the surface of the heat-rejection heat exchanger is formed as ribs for increasing the surface of the heat-rejection heat exchanger. This increases the interface of the heat-rejection heat exchanger with the ambient air flow thereby enhancing the efficiency of the heat-rejection heat exchanger.

In a further embodiment the non-stick coating covers at least said ribs or the tips of said ribs. As the tips of said ribs are very prone to soiling, this reduces the soiling of the surface of the heat-rejection heat exchanger considerably and covering only the tips reduces the amount of non-stick coating needed.

In a further embodiment the non-stick coating comprises nano particles. Non- stick coating comprising nano particles is very efficient in avoiding soiling the surface of the heat-rejection heat exchanger. Alternatively, the non-stick coating can be another coating having non-stick properties.

In a further embodiment a non-stick coating comprises nano cutting grains or edges. Such nano cutting grains and edges are very efficient in cutting long fibers contained in the ambient air flow and thus prevent these long fibers from depositing onto the surface or in air channels of the heat-rejection heat exchanger thereby blocking the airflow by the heat-rejection heat exchanger and reducing its efficiency.

In a further embodiment the air inlet is formed as at least one hole in a wall or panel of the furniture body. This is a very efficient and easy way of forming the air inlet. In an alternative embodiment the air inlet is formed as at least one hole formed in a panel attached to the furniture body. This allows easy access to the heat-rejection heat exchanger by removing the panel. The panel can be made of metal or plastic.

In a further embodiment a maximum cross section of one respective hole is not more than 12 mm in one dimension. This improves the security of the refrigerating sales furniture as it avoids that parts of a human body such as fingers are introduced through that hole into the compartment.

In a further embodiment the refrigerating sales furniture also comprises at least one fan for providing an ambient air flow through the heat-rejection heat exchanger. Providing such an airflow will improve the efficiency of the heat-rejection heat exchanger. The fan can be arranged behind the heat-rejection heat exchanger in order to suck the air by the surface of said heat-rejection heat exchanger or it may be arranged in front of the heat-rejection heat exchanger in order to blow the air by the surface of said heat-rejection heat exchanger. It is also possible that a fan is arranged on both sides of the heat-rejection heat exchanger, respectively.

In a further embodiment the air inlet is arranged at a height corresponding to the upper third of the heat-rejection heat exchanger. This avoids soiling of the heat-rejection heat exchanger even further as the air, which is sucked in from an even greater height, comprises even less soiling particles.

In a further embodiment the heat-rejection heat exchanger is located below the goods presentation and refrigeration space. As the heat-rejection heat exchanger has a considerable weight, arranging the heat-rejection heat exchanger in the bottom of the furniture below the goods presentation and refrigeration space reduces the statical requirements to the frame of the refrigerating sales furniture. As the frame needs to provide less stability the refrigerating sales fur- niture can be produced at lower costs. Furthermore, due to a low center of gravity the danger of tipping the furniture is considerably reduced. In a further embodiment other components of the vapor compression cycle are arranged below the goods presentation and refrigeration space, as well. In a further embodiment the refrigerating sales furniture comprises a shutting means for closing the goods presentation and refrigeration space. This shutting means may formed as a door or a blind. Such a shutting means enables closing the goods presentation and refrigeration space in order to save energy by avoiding that cool air is dropping out of said goods presentation and refrigeration space and/or to avoid that unauthorized persons take goods out of the goods presentation and refrigeration space.

The features, embodiments and advantages as described with respect to the refrigerating sales furniture can also be realized in terms of method steps, with the method for fabricating the refrigerating sales furniture according to the invention.

While the invention has been described with reference to exemplary embodi- ments, 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 many modifications may be made to adopt 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 not be limited to the particular embodiment disclosed, but that the invention include all embodiments falling within the scope of the dependent claims.

List of reference signs

2 refrigerating sales furniture

4 furniture body 6 goods presentation and refrigeration space

7 isolating ceiling

8 goods display deck

9 top

10 side member 1 1 compartment

12 front wall

13 rear top of the furniture

14 base

15 cover 16 air inlet

17 back wall

18 heat-rejection heat exchanger 22 fan

24 rear wall 26 air outlet

30 bend

Claims

1. Refrigerating sales furniture (2), comprising a furniture body (4) having a goods presentation and refrigeration space (6); a heat-rejection heat exchanger (18) of a vapor compression cycle, said heat-rejection heat exchanger (18) being positioned within the furniture body (4) and cooling, in operation, refrigerant flowing therethrough against ambient air; and at least one air inlet (16) leading an ambient air flow to the surface of the heat-rejection heat exchanger (18), said air inlet (16) being arranged at a greater height than the height of the middle portion of the heat-rejection heat exchang- er (18), thereby limiting, in operation, the amount of ambient air comprising soiling particles flowing through the heat-rejection heat exchanger (18).

2. Refrigerating sales furniture (2) of claim 1, wherein the air inlet (16) is arranged at the front of the furniture body (4).

3. Refrigerating sales furniture (2) of claim 1 or 2, wherein the goods presentation and refrigeration space (6) is open to the front of the furniture body (4).

4. Refrigerating sales furniture (2) of claim 3, wherein the goods presentation and refrigeration space (6) and the at least one air inlet (16) are positioned relative to each other such that ambient air flow led to the surface of the heat-rejection heat exchanger (18) through the at least one air inlet (16) comprises cold air dropping out of the goods presentation and refrigeration space (6).

5. Refrigerating sales furniture (2) of any of the preceding claims, wherein at least part of the surface of the heat-rejection heat exchanger (18) comprises an non-stick coating.

6. Refrigerating sales furniture (2) of claim 5, wherein the heat-rejection heat exchanger (18) comprises ribs enlarging its surface, and wherein the non-stick coating covers at least said ribs or the tips of said ribs.

7. Refrigerating sales furniture (2) of claim 5 or 6, wherein the non-stick coating comprises nano-particles.

8. Refrigerating sales furniture (2) of any of claims 5 to 7, wherein the nonstick coating can additionally comprise nano-cutting grains or edges, said nano- cutting grains or edges cutting fibers comprised in the ambient air flow for preventing the fibers from blocking the air flow by the surface of the heat-rejection heat exchanger (18).

9. Refrigerating sales furniture (2) of any of the preceding claims, wherein the air inlet (16) is formed as at least one hole in a wall or panel of the furniture body (4).

10. Refrigerating sales furniture (2) of claim 9, wherein the maximum cross-section of one respective hole is not more than 12 mm in one dimension.

11. Refrigerating sales furniture (2) of any of the preceding claims, further comprising at least one fan (22) for providing an ambient air flow through the heat- rejection heat exchanger (18).

12. Refrigerating sales furniture (2) of any of the preceding claims, wherein the air inlet (16) is arranged at a height corresponding to the upper third of the heat-rejection heat exchanger (18).

13. Refrigerating sales furniture (2) of any of the preceding claims, wherein the heat-rejection heat exchanger (18) is located below the goods presentation and refrigeration space (6).

14. Refrigerating sales furniture (2) of any of the preceding claims, comprising a shutting means for closing the goods presentation and refrigeration space (6).

15. Method for operating a refrigerating sales furniture having a furniture body (4) having a goods presentation and refrigeration space (6); a heat-rejection heat exchanger (18) of a vapor compression cycle, said heat-rejection heat exchanger (18) being positioned within the furniture body (4) and cooling, in operation, refrigerant flowing therethrough against ambient air; and at least one air inlet (16) being arranged at a greater height than the height of the middle portion of the heat-rejection heat exchanger (18); comprising the step of leading an ambient air flow to the surface of the heat-rejection heat exchanger (18) through the at least one air inlet (16), thereby limiting the amount of ambient air comprising soiling particles flowing through the heat-rejection heat exchanger (18).

16. Method according to claim 15, wherein the goods presentation and refrigeration space (6) is open to the front of the furniture body (4) and wherein the goods presentation and refrigeration space (6) and the at least one air inlet (16) are positioned relative to each other, wherein the ambient air flow being led to the surface of the heat-rejection heat exchanger (18) through the at least one air inlet (16) comprises cold air dropping out of the goods presentation and refrigeration space (6).

17. Method according to claim 15 or 16, wherein at least part of the surface of the heat-rejection heat exchanger (18) is covered by an non-stick coating, wherein the sticking of soiling particles comprised in the ambient air flowing through the heat-rejection heat exchanger (18) on the surface of said heat-rejection heat exchanger (18) is prevented.

18. Method according to claim 17, wherein the non-stick coating comprises nano-cutting grains or edges, wherein said nano-cutting grains or edges cut fibers comprised in the ambient air flow and prevent them from depositing on the surface of the heat-rejection heat exchanger (18).