AIR CURTAIN SYSTEM FOR OPEN DISPLAY REFRIGERATORS

Abstract

The present invention provides an open display refrigerator comprising: a refrigerated storage space, air in the refrigerated storage space being separated from air exterior to the open display refrigerator by an air curtain established by a fan which blows air towards an air outlet, air in the air curtain being recovered by an air inlet which recirculates the air from the air curtain into an air duct coupled to the air outlet, and an air guide coupled to the air outlet or air duct and extending from the air outlet such that it bypasses a portion of a void between the uppermost shelf and the air outlet, whereby the air curtain is established between an extremity of the portion of the void proximal to the air inlet and the air inlet.

Claims

1. An apparatus, comprising: a housing defining a refrigerated storage space; a shelf disposed within the refrigerated storage area; an air outlet; a fan configured to blows air towards the air outlet to form an air curtain that separates the refrigerated storage area from an exterior of the housing; an air inlet; an air duct that fluidically couples the air inlet to the air outlet such that air from the air curtain can be recirculated through the air outlet; and an air guide projecting from the air outlet, a length of the air guide configured to cause the air curtain to bypass at least a portion of a void between the shelf and the air outlet.

2. (canceled)

3. The apparatus of claim 1, wherein the shelf is an uppermost shelf that is at an angle to the horizontal such that a rear edge of the shelf is higher than a front edge of the shelf.

4. The apparatus of claim 1, wherein the air guide comprises an air guide inlet coupled to the air outlet and an air guide outlet at which the air curtain is established, the air guide inlet separated by the air guide outlet by the length of the air guide.

5. (canceled)

6. The apparatus of claim 4, wherein a cross sectional area of the air guide inlet is larger than a cross sectional area of an air guide outlet such that a velocity of air increases as it passes through the air guide.

7. The apparatus of claim 4, wherein a cross sectional area of the air guide inlet is smaller than a cross sectional area of an air guide outlet.

8.-9. (canceled)

10. The apparatus of claim 1, further comprising a honeycomb structure positioned in the air outlet, the honeycomb structure being a cellular matrix of channels which extend in a longitudinal direction parallel to the air flow.

11. The apparatus of claim 4, further comprising a honeycomb structure positioned in the air guide outlet, the honeycomb structure being a cellular matrix of channels which extend in a longitudinal direction parallel to the air flow of the air curtain.

12.-13. (canceled)

14. A method, comprising: measuring an initial temperature difference between a warmest initial temperature sensed by an array of temperature sensors disposed within a refrigerated housing and a coldest initial temperature sensed by the array of temperature sensors, the initial temperature difference measured with no air guide coupled to an air outlet that is configured to produce air for an air curtain that separates an interior of the refrigerated housing from an exterior of the refrigerated housing; coupling a first air guide to the air outlet such that a length of the first air guide is causes the air curtain to bypass a portion of a void between an uppermost shelf within the refrigerated housing and the air outlet; measuring a first temperature difference between a warmest first temperature sensed by the array of temperature sensors when the first air guide is coupled to the air outlet and a coldest first temperature sensed by the array of temperature sensors when the first air guide is coupled to the air guide outlet; removing the first air guide from the air outlet; coupling a second air guide to the air outlet after removing the first air guide from the air outlet, the second air guide being different from the first air guide, the second air guide coupled to the air outlet such that a length of the second air guide causes the air curtain to bypass a portion of the void between the uppermost shelf and the air outlet; measuring a second temperature difference between a warmest second temperature sensed by the array of temperature sensors when the second air guide is coupled to the air outlet and a coldest second temperature sensed by the array of temperature sensors when the second air guide is coupled to the air outlet; measuring a second temperature difference between a warmest second temperature sensed by the array of temperature sensors when the second air guide is coupled to the outlet and a second coldest temperature sensed by the array of temperature sensors when the second air guide is coupled to the air outlet; and selecting the second air guide based on at least one of a difference between the initial temperature difference and the second temperature difference exceeding a threshold, or the second temperature difference being greater than the first temperature difference.

15.-17. (canceled)

18. The method of claim 14, further comprising adjusting the second air guide such that the second temperature difference is further reduced.

19.-23. (canceled)

24. A method, comprising: coupling an air guide to an air outlet that is configured to produce air for an air curtain that separates an interior of a refrigerated housing from an exterior of a refrigerated housing, the air guide having an air guiding surface configured to cause the air curtain to bypass a portion of a void between an uppermost shelf in the refrigerated housing and the air outlet; and adjusting the air guide to reduce a difference between a warmest temperature measured by at least one temperature sensor disposed within the interior of the refrigerated housing and a coldest temperature measured by the at least one temperature sensor.

25. (canceled)

26. The method of claim 24, wherein the air guide is coupled to the air outlet by clips integral to the air guide.

27. The method of claim 24, wherein the air guide is coupled to the air outlet with at least one of screws or rivets.

28. The method of claim 24, wherein the air guide is coupled to the air outlet with at least one of mastic or adhesive.

29. The method of claim 24, wherein the air guide comprises an air guide inlet through which air enters and an air guide outlet at which the air curtain is established, and wherein the air guide outlet is offset relative to the air guide inlet.

30. The method of claim 24, wherein the air guide comprises an air guide inlet through which the air enters and an air guide outlet at which the air curtain is established, and wherein the air guide outlet is aligned with the air guide inlet.

31. The method of claim 24, wherein a cross sectional area of an air guide inlet is larger than a cross sectional area of an air guide outlet such that a velocity of air increases as it passes through the air guide.

32. The method of claim 24, wherein a cross sectional area of an air guide inlet is smaller than a cross sectional area of an air guide outlet.

33. The method of claim 24, wherein a cross sectional area of air guide inlet is the same, or is substantially the same, as a cross sectional area of an air guide outlet.

34. The method of claim 24, further comprising removing a honeycomb structure from at least one of the air guide outlet or air duct, the honeycomb structure being a cellular matrix of channels which extend in a longitudinal direction parallel to the air flow of the air curtain.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0058] Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

[0059] FIG. 1 shows an open display refrigerator in which the shelves are angled and a void is formed between the uppermost shelf and the air outlet.

[0060] FIG. 2 shows the difference between the intended line of the air curtain of the open display refrigerator of FIG. 1 and the actual path of the air curtain due to the void between the uppermost shelf and the air outlet and the warm air which is drawn from the top of the refrigerator.

[0061] FIG. 3 shows an open air refrigerator with an air guide coupled to the air outlet.

[0062] FIG. 4 shows method steps for selecting an air guide from a plurality of air guides for use with a refrigerator.

DETAILED DESCRIPTION

[0063] FIG. 1 shows a cross-section through an open display refrigerator 1. The refrigerator has a storage space 2 that is maintained at a lower than ambient temperature. Within the storage space 2, there are four angled storages shelves 3a-3d. Different embodiments may have one, two, three, five or any number of storage shelves which may be flat, may be at an angle or may be a mix of angled and flat shelves. A typical angle for the angled storage shelves is 20°, however shelves at other angles may be used, as long as the product being refrigerated does not slide off of the shelves. As can be seen, a void 6 is formed between the uppermost storage shelf 3a and the air outlet 4. The refrigerator 1 establishes an air curtain (not shown) by a fan (not shown) which blows cold air towards an air outlet 4, out of the air outlet 4 and towards an air inlet 5. Air inlet 5 recovers air from the air curtain and a fan (not shown) within the refrigerator 1 recirculates the air to the air outlet 4. A cooling unit or heat exchanger (not shown) within the refrigerator 1 maintains the recirculated air (and hence the air blown through the air outlet 4 to form the air curtain) at a desired temperature. The desired temperature is chosen to be lower than ambient and acts to prevent cold air in the storage space 2 from mixing with warm air exterior to the refrigerator.

[0064] In FIG. 2, the impact of the void 6 and the impact of warm air being drawn around the top of the refrigerator on the intended path of the air curtain is shown. The path of the warm air is indicated by the curved arrow 7. The intended path of the air curtain is indicated by the dotted line 8 and the deflected path of the air curtain is indicated by the dashed line 9. As can be seen, the air curtain moves towards the interior of the refrigerator in an unintended manner, which leads to increased temperatures at the bottom of the refrigerated storage space 2, when compared to a refrigerator that has a generally linear air curtain.

[0065] FIG. 3 shows a solution as provided by the present invention to the problem associated with the void between the uppermost shelf and the air outlet and also the problem associated with warm air being drawn from the top of the refrigerator and impinging on the air curtain. A cross-section through the open display refrigerator 1 is shown. As in FIGS. 1 and 2, the refrigerator 1 comprises a refrigerated storage space 2. Air in the refrigerated storage space 2 is separated from air exterior to the open display refrigerator 1 by an air curtain, indicated by the dashed line 10, established by a fan (not shown) which blows air towards an air outlet 4 and through an air guide 12 coupled to the air outlet 4 towards a corresponding air inlet, which recovers air from the air curtain for recirculation through an air duct 11 to the air guide 12. The air guide extends from the air outlet 4 such that it bypasses a portion of the void 6 formed between the uppermost shelf 3a and the air outlet 4. As shown, the air guide outlet may be offset away from, or be offset distal to, the rear wall of the refrigerated storage space with respect to the air guide inlet. This results in an air curtain that follows a more linear path, as the effect of the void on the air curtain is reduced. This is realised because the air guide bypasses a portion of the void between the uppermost shelf and the air outlet and prevents air from rushing into the void, hence the effect of the void on the path of the air curtain is reduced and the air curtain follows a more linear path. Further, as the air guide extends from the air outlet, the air guide helps prevent warm air proximate the top exterior surface of the refrigerator from being drawn around the front uppermost edge of the refrigerator and impinging on the air curtain as the air curtain leaves the air outlet, because the air guide forms a barrier that extends from the air outlet and the air curtain is no longer proximal to the warm air. An advantage of the air guide only bypassing a portion of the void is that the air curtain follows the intended path more closely and users can easily see and access items on the top angled shelf.

[0066] Although the air guide 12 shown in FIG. 3 shows an air guide wherein the air guide outlet is offset away from, or is offset distal to, the rear wall of the refrigerated storage space with respect to the air guide inlet, other air guides may be used to achieve the same technical effect. For example, an air guide comprising an air guide inlet through which the air enters and an air guide outlet at which the air curtain is established, wherein the air guide outlet is aligned, or is substantially aligned, with the air guide inlet, may be used. In other embodiments, the body of the air guide may have a chicane shape or an “S” shape. The chicane shape or the “S” shape may be made up of a curve in a first direction and a curve in a second direction. Alternatively, the body of the air guide may comprise a single curve. In some embodiments a part of the air guide may extend into the duct. In particular, an outermost side or a distal side (with respect to the refrigerated interior) of the air guide may extend into the duct. A technical advantage of all of these configurations is that the air guide can be better customised to work with the air flow characteristics of different fridges.

[0067] A cross sectional area of the air guide inlet of the air guide 12 shown in FIG. 3 is substantially the same as a cross sectional area of an air guide outlet. Air guides with different cross-sectional areas may also be used, for example an air guide wherein a cross sectional area of the air guide inlet is larger than a cross sectional area of an air guide outlet may be used. Alternatively, an air guide wherein a cross sectional area of the air guide inlet is smaller than a cross sectional area of an air guide outlet may also be used.

[0068] The air guide 12 may be coupled to the refrigerator using any of screws, rivets, mastic, adhesive or any other way of attachment known to the person skilled in the art.

[0069] FIG. 4 shows a method of selecting an air guide from a plurality of air guides for use with an open display refrigerator, wherein the open display refrigerator comprises a refrigerated storage space, air in the refrigerated storage space being separated from air exterior to the open display refrigerator by an air curtain established by a fan which blows air towards an air outlet, air in the air curtain being recovered by an air inlet which recirculates the air from the air curtain into an air duct coupled to the air outlet and wherein the method comprises: providing an array of temperature sensors within an interior of the open display refrigerator 100; measuring an initial temperature difference between the warmest temperature recorded by the array of temperature sensors and the coldest temperature recorded by the array of temperature sensors 101; coupling one or more air guides to the air outlet or air duct such that the or each air guide extends from the air outlet and bypasses a portion of a void between the uppermost shelf and the air outlet, whereby the air curtain is established between an extremity of the portion of the void proximal to the air inlet and the air inlet 102; measuring a respective final temperature difference associated with the or each air guide, the or each final temperature difference being the temperature difference between the warmest temperature recorded by the array of temperature sensors and the coldest temperature recorded by the array of temperature sensors after the associated air guide has been coupled to the air outlet or air duct 103; selecting an air guide from the one or more air guides, whereby the difference between the initial temperature difference and the final temperature difference associated with the selected air guide is at least a threshold temperature difference, or selecting the air guide from the one or more air guides for which the difference between the initial temperature difference and the associated final temperature difference is greatest 104.

[0070] In some embodiments, the array of temperature sensors are provided within the refrigerated storage space. In some embodiments, a temperature sensor of the array of temperature sensors is provided proximate the air inlet. In some embodiments the air guide, and hence the path of the air curtain, is adjusted such that the temperature difference is further reduced.

[0071] In some embodiments, the method may include steps that comprise measuring the temperature by placing numerous jelly-bricks (examples of jelly-bricks known in the art are Tylose packs or M-Packs) on the shelves of the refrigerator, wherein each jelly-brick has its own temperature probe, each of which makes up the array of temperature probes, so that the temperature at different points in the fridge can be tracked. As the location of the warmest jelly-brick and the location of the coolest jelly-brick may change with the addition of the air guide and/or adjustments made to the air guide, the difference between the warmest jelly-brick and the coolest jelly brick may be measured as opposed to measuring the same jelly-bricks before and after adding or adjusting the air guide.