REFRIGERATED CASE WITH ANTI-CONDENSATION CONTROL SYSTEM

• US 20080115519A1
• Filed: 01/29/2008
• Published: 05/22/2008
• Est. Priority Date: 05/10/2004
• Status: Abandoned Application

• Current Assignee: Computer Process Controls Incorporated (Emerson Electric Company)
• Original Assignee: Computer Process Controls Incorporated (Emerson Electric Company)
• Inventors: Vogh, Richard
• Application Number:
  US12/021,766
• Publication Number:
  US 20080115519A1
• Time in Patent Office: Days
• US Class Current: 62/247
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 2013/221 to avoid the formation of condensate, e.g. dew
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: F25D 21/04 Preventing the formation of frost or condensate

Abstract

A refrigerated case for storing food product includes a sensor module and a control module. The control module receives input from the sensor module and compares the input to a set point to generate an output indicative of a difference between the input and the set point, and further updates the output based on the input from the sensor module. A heater module controls a heater attached to a control surface of the refrigerated case based on the output to maintain a temperature of air adjacent the sensor module above a dew point temperature of room air.

Claims

1. A refrigerated case for storing food product comprising:

a sensor module;

a control module receiving an input from said sensor module and operable to compare said input to a set point and generate an output indicative of a difference between said input and said set point, said control module updating said output based on said input from said sensor module; and

a heater modulator operable to control a heater attached to a control surface of the refrigerated case based on said output to maintain a temperature of air adjacent said sensor module above a dew point temperature of room air.

2. The refrigerated case of claim 1, wherein said control module uses closed-loop control to control said heater.

3. The refrigerated case of claim 1, wherein said sensor module includes a sensor mounted to a control surface selected from the group comprising a glass pane, a casing, a frame, a rail, or a wall of the refrigerated case.

4. The refrigerated case of claim 1, wherein said sensor module includes a temperature sensor.

5. The refrigerated case of claim 1, wherein said sensor module includes a relative humidity sensor.

6. The refrigerated case of claim 5, wherein said sensor module includes a temperature sensor, said control module determining a dew point based on information received from said relative humidity sensor and said temperature sensor.

7. The refrigerated case of claim 1, wherein said sensor module includes a dew point sensor.

8. The refrigerated case of claim 1, wherein said control module includes a controller and at least one of an adder-subtractor and a limiter.

9. The refrigerated case of claim 1, wherein said control module is in communication with a main controller.

10. A bank of refrigerated cases for storing food product comprising:

a sensor module having a first sensor positioned adjacent a control surface of at least one of the refrigerated cases;

a control module receiving an input from said sensor module and operable to compare said input to a set point and generate an output indicative of a difference between said input and said set point, said control module updating said output based on said input from said sensor module; and

a heater modulator operable to control a heater attached to said control surface of said at least one of the refrigerated cases based on said output to maintain a temperature of air adjacent said first sensor above a dew point temperature of room air.

11. The bank of refrigerated cases of claim 10, wherein said control module uses closed-loop control to control said heater.

12. The bank of refrigerated cases of claim 10, further comprising a plurality of sensor modules respectively associated with each refrigerated case.

13. The bank of refrigerated cases of claim 10, wherein said first sensor is a temperature sensor.

14. The bank of refrigerated cases of claim 10, wherein said sensor module further includes a second sensor.

15. The bank of refrigerated cases of claim 14, wherein said second sensor is a relative humidity sensor.

16. The bank of refrigerated cases of claim 15, wherein said control module determines a dew point based on information received from said relative humidity sensor and said first sensor.

17. The bank of refrigerated cases of claim 16, wherein said first sensor is a temperature sensor.

18. The bank of refrigerated cases of claim 10, wherein said control surface is selected from the group comprising a glass pane, a casing, a frame, a rail, or a wall of said at least one of the refrigerated cases.

19. The bank of refrigerated cases of claim 10, wherein said control module is in communication with a main controller.

20. The bank of refrigerated cases of claim 10, wherein said first sensor is a dew point sensor.