Refrigerated display cabinet utilizing a radial cross flow fan

Patent metadata

Field	Value
Publication number	US-11559147-B2
Application number	US-201916405856-A
Country	US
Kind code	B2
Filing date	May 7, 2019
Priority date	May 7, 2019
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

A refrigerated display case includes a housing surrounding multiple shelves. An air distribution gap is defined behind the shelves. An air return passage is defined below the shelves. A radial cross-flow fan is disposed in a fan region of the air return passage. The radial cross-flow fan includes an output connected to the air distribution gap. A primary cooling microchannel heat exchanger is disposed in the fan region downstream of the radial cross-flow fan such that air output from the radial cross-flow fan to the air distribution gap passes through the primary cooling microchannel heat exchanger. A pre-cooler microchannel heat exchanger is disposed upstream of the primary cooling microchannel heat exchanger.

First claim

The invention claimed is:

1. A refrigerated display case comprising:
a housing surrounding a plurality of shelves;
an air distribution gap defined behind the plurality of shelves;
an air return passage defined below the plurality of shelves;
a radial cross-flow fan disposed in a fan region of the air return passage, the radial cross-flow fan having an output connected to the air distribution gap;
a primary cooling microchannel heat exchanger disposed in the fan region downstream of the radial cross-flow fan such that air output from the radial cross-flow fan to the air distribution gap passes through the primary cooling microchannel heat exchanger;
a pre-cooler microchannel heat exchanger disposed upstream of the primary cooling microchannel heat exchanger; and
the pre-cooler microchannel heat exchanger having a first saturation temperature and the primary cooling microchannel heat exchanger having a second saturation cooling temperature, and where the second saturation temperature is lower than the first saturation temperature.

2. The refrigerated display case of claim 1 , wherein the pre-cooler microchannel heat exchanger is disposed downstream of the cross-flow fan.

3. The refrigerated display case of claim 2 , wherein the pre-cooler microchannel heat exchanger connects the output of the radial cross-flow fan to the air distribution gap.

4. The refrigerated display case of claim 3 , wherein the primary cooling microchannel heat exchanger is disposed immediately downstream of the pre-cooler microchannel heat exchanger.

5. The refrigerated display case of claim 1 , wherein the pre-cooler microchannel heat exchanger is disposed upstream of the radial cross-flow fan.

6. The refrigerated display case of claim 5 , wherein the pre-cooler microchannel heat exchanger includes a cooled air output connected to an input of the radial cross-flow fan.

7. The refrigerated display case of claim 1 , wherein the first saturation temperature is below a temperature required to extract moisture from the return air and above a minimum cooling temperature for the plurality of shelves.

8. The refrigerated display case of claim 7 , wherein the second saturation temperature is above a frost temperature.

9. The refrigerated display case of claim 1 , further comprising a top duct define above the plurality of shelves and connecting the air distribution gap to an air curtain fan and a third microchannel heat exchanger connected to the air curtain fan such that cooled air is provided to the air curtain fan.

10. The refrigerated display case of claim 1 , wherein the fan region is at a downstream end of the air return passage.

11. A method of cooling shelves in a refrigerated display cabinet comprising:
driving air through a cooling circuit using a radial cross-flow fan;
passing the air through a primary microchannel heat exchanger, thereby cooling the air below a minimum cooling temperature of at least one shelf; and
extracting moisture from the air using a pre-cooler microchannel heat exchanger prior to passing the air through the primary microchannel heat exchanger; and
operating the primary microchannel heat exchanger at a saturation temperature below a frost point and operating the pre-cooler microchannel heat exchanger at a temperature above the frost point and below a condensation point.

12. A method of cooling shelves in a refrigerated display cabinet comprising:
driving air through a cooling circuit using a radial cross-flow fan;
passing the air through a primary microchannel heat exchanger, thereby cooling the air below a minimum cooling temperature of at least one shelf;
extracting moisture from the air using a pre-cooler microchannel heat exchanger prior to passing the air through the primary microchannel heat exchanger; and
deactivating the pre-cooler microchannel heat exchanger in response to a controller determining a low load period.

13. The method of claim 12 , wherein the pre-cooler microchannel heat exchanger is downstream of the radial cross-flow fan and upstream of the primary microchannel heat exchanger.

14. The method of claim 12 , wherein the pre-cooler microchannel heat exchanger is upstream of the radial cross-flow fan.

15. The method of claim 12 , further comprising driving at least a portion of the air to create a downward flowing air curtain using an air curtain fan.

16. The method of claim 15 , further comprising cooling the at least the portion of the air immediately prior to the air curtain fan using a micro-channel heat exchanger.

17. The method of claim 12 , further comprising operating the primary microchannel heat exchanger at a saturation temperature below a frost point and operating the pre-cooler microchannel heat exchanger at a temperature above the frost point and below a condensation point.

18. The method of claim 12 , further comprising reactivating the pre-cooler microchannel heat exchanger in response to a controller detecting a door opening.

19. A refrigerated display case comprising:
a housing surrounding a plurality of shelves;
an air distribution gap defined behind the plurality of shelves;
an air return passage defined below the plurality of shelves;
a radial cross-flow fan disposed in a fan region of the air return passage, the radial cross-flow fan having an output connected to the air distribution gap;
a primary cooling microchannel heat exchanger disposed in the fan region downstream of the radial cross-flow fan such that air output from the radial cross-flow fan to the air distribution gap passes through the primary cooling microchannel heat exchanger;
a pre-cooler microchannel heat exchanger disposed upstream of the primary cooling microchannel heat exchanger; and
a controller configured to deactivate the pre-cooler microchannel heat exchanger during a low load period.

Assignees

• Carrier Corp

Inventors

• Joardar Arindom

Classifications

• F25B2400/22

  Refrigeration systems for supermarkets · CPC title

• A47F3/0491

  Cooled shelves · CPC title

• A47F3/0478

  Control or safety arrangements · CPC title

• A47F3/0447 Primary

  with air curtains · CPC title

• A47F2003/046

  with shelves having air ducts · CPC title