Patent Application
20230066886
The disclosure relates to a refrigerated display case.
The display of chilled or frozen items is commonplace in many retail environments, most notably in supermarkets. Such items are often displayed in refrigerated display cases having hinged or sliding doors. Refrigerated display cases utilise an air curtain which is cooled to below ambient temperature and propelled downward, across the front of the display case and behind the door(s).
The energy consumed by such refrigerated display cases presents a significant contribution to the overall energy consumption of the supermarket. It is therefore desirable to improve the efficiency of refrigerated display cases.
According to an aspect of the disclosure there is provided a refrigerated display case comprising: a refrigerated display area; an air outlet and an air inlet opening into the display area and spaced from one another; a duct fluidically coupling the air inlet to the air outlet, the duct being configured to direct air flow out of the air outlet across the display area and toward the air inlet to form an air curtain across the display area; and an airflow inhibiting apparatus comprising: a conduit having an inlet and a plurality of outlet apertures, the outlet apertures arranged around a perimeter of an upper portion of an opening to the refrigerated display area; a fan fluidically connected to the conduit and configured to draw air into the conduit via the inlet and to discharge a jet of air from each of the plurality of outlet apertures; wherein the outlet apertures are each arranged such that the jet of air is angled outwards away from the display area to repel ambient air away from the display area so as to prevent airflow into the display area.
The outlet apertures may be provided around the upper portion of the opening only.
The conduit may form a frame e.g. a door frame.
The frame may comprise a lower horizontal section, an upper horizontal section and a pair of vertical sections. The inlet may be formed in the lower horizontal section and the outlet apertures may be arranged across the upper horizontal section and along upper portions of the vertical sections.
The refrigerated display case may further comprise a door configured to selectively close the opening to the refrigerated display area. The airflow inhibiting apparatus and more specifically the outlet apertures may act to repel ambient air away from the display area when the door is opened so as to prevent airflow into the display area.
The refrigerated display case may comprise a plurality of doors each configured to selectively close a respective opening to the refrigerated display area, wherein each opening is provided with an inlet and a plurality of outlet apertures.
The inlet and the plurality of outlet apertures of each opening may be connected to a common conduit.
The inlet of the conduit may be provided at a lower portion of the opening and may be configured to receive air which spills out from the air curtain when the door is opened.
The airflow inhibiting apparatus may be configured to generate the jets of air from the outlet apertures only when the door is opened.
The airflow inhibiting apparatus may comprise a valve which is configured to close the outlet apertures when the door is closed and/or a valve which is configured to close the inlet of the conduit when the door is closed.
The valve may comprise one or more seal members which are provided on the door and which cover the outlet apertures and/or inlet when the door is closed.
The fan may be configured to be activated continuously whether the door is open or closed.
The airflow inhibiting apparatus may comprise a sensor which is configured to detect when the door is opened and provides a control signal to activate the fan when the door is open.
A guide portion may be provided adjacent each of the outlet apertures to direct the jet of air in a predefined direction.
The guide portion may be disposed within the conduit.
The outlet apertures may be each arranged such that the jet of air is angled outwards at an angle of 20 to 40 degrees.
The outlet apertures may be each arranged such that the jet of air is angled outwards at an angle of 30 degrees.
The refrigerated display case may be a freezer display case.
For a better understanding of the disclosure, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:-
The lower, back and upper panels 10, 12, 14 and the doors 9 form a display area 15 which is provided with a plurality of shelves 17 (four are shown) on which items may be displayed. The shelves 17 are affixed to the back panel 12.
As shown, the lower, back and upper panels 10, 12, 14 are spaced from the respective lower, back and upper walls 4, 6, 8 to form a duct 16. An intake grille 18 is provided at the lower panel 10 to form an inlet to the duct 16. Similarly, a discharge grille 20 is provided at the upper panel 14 to form an outlet from the duct 16. The intake grille 18 and the discharge grille 20 are thus fluidically coupled to one another by the duct 16. The intake grille 18 and the discharge grille 20 are spaced from the back panel 12 toward the front of the cabinet portion and ahead of the shelves 17.
A fan 22 and a heat exchanger 24 are located within the duct 16 adjacent to the intake grille 18 and thus are disposed between the lower wall 4 and the lower panel 10. The fan 22 draws air into the duct 16 via the intake grille 18 which then passes through the heat exchanger 24 where it is cooled to well below the ambient temperature.
After passing through the heat exchanger 24, the air continues through the duct 16 between the back wall 6 and the back panel 12. The back panel 12 is perforated allowing air to pass from the duct 16 into the display area 15 where it cools items located on the shelves 17 and on the lower panel 10.
The remaining air flows through the duct 16 to the discharge grille 20. The air is ejected from the discharge grille 20 and descends behind the doors 9 over the front of the display area 15 to form an air curtain 26. The air curtain 26 passes from the discharge grille 20 to the intake grille 18, where it is drawn in by the fan 22 and recirculated through the duct 16.
In this example, the discharge grille 20 is provided with a honeycomb panel which rectifies the air flow as it exits the discharge grille 20 to provide flow with reduced turbulence.
It has been identified that when one of the doors 9 is opened, either by sliding or pivoting, warm ambient air is drawn into the display case 2 towards the top of the open doored region and cold air from within the display case spills out towards the bottom of the open doored region. Such air flows become more pronounced as the temperature within the display case is reduced since the buoyancy effects become stronger. Accordingly, this phenomenon is seen more readily in refrigerated display cases operating at freezing temperatures (i.e. freezer display cases).
As shown in
The horizontal and vertical sections of the frame 132 are hollow and are connected to one another to form a continuous conduit.
As best shown in
The vertical sections 138a-138d are also provided with outlet slots 146. The outlet slots 146 are only provided over an upper portion of the vertical sections 138a-138d and a lower portion of the vertical sections 138a-138d is devoid of any outlet slots 146. For example, the outlet slots 146 may only cover the upper third of the vertical sections 138a-138d and the bottom two-thirds may not be provided with any outlet slots 146.
Portions of the vertical sections 138a-138d and the upper horizontal section 136 adjacent the corners between the vertical sections 138a-138d and the upper horizontal section 136 may not include any outlet slots 144, 146.
The first and fourth vertical sections 138a, 138d are provided with outlet slots 146 along an inner surface, whereas the second and third vertical sections 138b, 138c are provided with outlet slots along two opposing surfaces, as shown in
The outlet slots 144, 146 are angled outwards away from the display area 15. In particular, a guide portion 148 formed by a pair of a parallel plates is provided adjacent each outlet slot 144, 146. As shown, the guide portions 148 are located internally within the frame 132 (i.e. within the rectangular cross-section of the frame 132). In other examples, the guide portions 148 may extend out of the frame 132. The guide portions 148 may be angled outwards at an angle of 20 to 40 degrees, and more particularly 30 degrees, from the plane of the opening 140a-140c (i.e. from the vertical or horizontal). As shown in
As shown in
As shown, the door 9 comprises a seal member 152 which runs vertically along an edge of the door. The seal member 152 forms a lip which projects inwardly from the door 9 (e.g. from a frame of the door 9). As shown in
As shown in
Although not shown, similar seal members 152 are also provided along horizontal edges of the door 9 to seal against the lower and upper horizontal sections 134, 136 of the frame 132 and thus selectively close the inlet and outlet slots 142, 144. In some examples, a single seal member 152 may extend around the entire perimeter of the door 9.
The or each seal member 152 effectively forms a valve which selectively closes the slots in the frame 132 when the door 9 is closed. It will be appreciated that other forms of valves may be used to close the inlet and/or outlet slots (whether directly or indirectly via an obstruction positioned along the length of the conduit).
When the door 9 is opened, cold air from the air curtain 26 deviates outwards from its normal trajectory (see the dashed arrow in
The air from the outlet slots 144, 146 forms a barrier which acts to repel warm ambient air which would otherwise be drawn into the display case 102 towards the top of the opening 140b. The airflow inhibiting apparatus 130 is thus able to prevent warm air from infiltrating into the display case 102 and thus improves efficiency.
Although the operation of the airflow inhibiting apparatus 130 has been described above in relation to the opening of a single door, the same principles apply where multiple doors are opened simultaneously.
In some examples, the fan 150 may be activated only when one or more of the doors are opened. For example, a sensor may be used to identify when a door is opened and provide a control signal to operate the fan 150. The seal members 152 would block outlet slots 144, 146 for doors which are not opened such that air is directed only to those doors which are open.
In other examples, the fan 150 may operate continuously regardless of whether the doors are opened or closed. It has been found that this does not provide a significant increase in energy consumption. As the seal members 152 close the outlet slots 144, 146, the fan 150 may pressurise the frame 132 when the doors 9 are closed. This may be beneficial in that the conduit may be primed with air before the doors 9 are opened and thus can react more quickly to repel the ambient air.
In other examples, air may be blown from the outlet slots 144, 146 even when the doors are closed. Accordingly, it is not necessary for the fans to be triggered only when the doors are opened, nor to provide any seal members 152 or other valves.
In other examples, the inlet may be formed as a single slot in the lower horizontal section 134.
It will be appreciated that the refrigerated display case 102 may contain any number of doors and the frame 132 may be configured accordingly. Further, the frame 132 may be divided into discrete sections for each door which form separate conduits. In this case, each of the sections may comprise its own fan 150. In some examples, the fan 150 of each section may only be operated when its respective door is opened. The disclosure may also be applied to open refrigerated display cases which do not have doors. For example, the disclosure may be implemented in an open refrigerated display case which is configured to allow roll containers (i.e. cages), such as those used for milk and other dairy products, to be rolled directly into the refrigerated display case either through the front or the rear of the refrigerated display case. Where the roll container is introduced through the front of the refrigerated display case, the vertical sections may be spaced a greater distance from one another than the width of the roll container so that the roll container can pass therebetween. The lower horizontal section may also be of sufficiently low profile that the roll container can easily roll over it. The lower horizontal section may be partially or fully recessed in the floor to facilitate this.
In other examples, a conduit may be formed between the inlet slots and the outlet slots which does not form a door frame. For example, the conduit may be routed around the rear of the display case in a similar way to the duct 16. Further, in other examples, the airflow inhibiting apparatus 130 may utilise ambient air, rather than air which has spilt out from the air curtain 26. Alternatively, the air may be refrigerated air which is taken from the duct 16 before it exits the discharge grille 20 and is accelerated further to provide a higher velocity at the outlet slots 144, 146.
Although the doors of the display case 102 have been described as being hinged, it will be appreciated that they may instead be formed as sliding doors. In this case, the seal members 152 may be adapted so that they perform the same function of obstructing the inlet and outlet slots 142, 144, 146 when the door is closed and clearing the inlet and outlet slots 142, 144, 146 when the door is opened.
It will be appreciated that the inlet and outlet slots need not be slot-shaped and other forms of aperture may be used.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2001463.5 | Feb 2020 | GB | national |
This application is the U.S. National Stage of PCT/EP2021/052184 filed on Jan. 29, 2021, which claims priority of UK Patent Application No. GB 2001463.5 filed on Feb. 3, 2020, the contents of which are incorporated herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/052184 | 1/29/2021 | WO |
