Wireless method and apparatus for monitoring and controlling food temperature

• US 6,502,409 B1
• Filed: 05/03/2000
• Issued: 01/07/2003
• Est. Priority Date: 05/03/2000
• Status: Expired due to Term

• Current Assignee: Emerson Climate Technologies Retail Solutions Incorporated (Emerson Electric Company)
• Original Assignee: Computer Process Controls Incorporated (Emerson Electric Company)
• Inventors: Chabucos, Jim, Rippe, Herb, Gatling, William, Singh, Abtar
• Primary Examiner(s): WAYNER, WILLIAM E
• Application Number:
  US09/564,173
• Time in Patent Office: 979 Days
• Field of Search: 236/51, 236/78.B, 374/134, 62/80--75, 625/10
• US Class Current: 62/80
• CPC Class Codes: F25B 2400/075 with parallel compressors
• CPC Class Codes: F25B 2400/22 Refrigeration systems for supermarkets
• CPC Class Codes: F25B 2600/07 Remote controls
• CPC Class Codes: F25D 2500/04 Calculation of parameters
• CPC Class Codes: F25D 2700/10 Sensors measuring the temperature of the evaporator
• CPC Class Codes: F25D 2700/12 Sensors measuring the inside temperature
• CPC Class Codes: F25D 2700/123 more than one sensor measuring the inside temperature in a compartment
• CPC Class Codes: F25D 2700/16 Sensors measuring the temperature of products
• CPC Class Codes: F25D 29/00 Arrangement or mounting of control or safety devices
• CPC Class Codes: G01K 2007/422 Dummy objects used for estimating temperature of real objects
• CPC Class Codes: G05D 23/1905 associated with tele control

Abstract

A system and method for controlling refrigeration including a simulated product temperature sensor operable to measure a simulated product temperature from a refrigeration case and a transceiver in communication with said simulated product temperature sensor and operable to wirelessly transmit data. A receiver receives the wirelessly transmitted data and a controller in communication with the receiver controls the refrigeration system based upon the wirelessly transmitted data from the refrigeration case.

Claims

1. A system for controlling refrigeration, comprising:

at least one refrigeration case;

a simulated product temperature sensor operable to measure a simulated product temperature from said at least one refrigeration case;

a transceiver in communication with said simulated product temperature sensor and operable to wirelessly transmit data including said simulated product temperature;

a receiver adapted to receive said wirelessly transmitted data including said simulated product temperature;

a controller in communication with said receiver and operable to control a temperature of said at least one refrigeration case based upon said wirelessly transmitted data from said at least one refrigeration case.

2. The system of claim 1 wherein said simulated product temperature sensor includes a housing containing a thermal mass having thermo-physical properties similar to food product, and a thermistor for measuring the temperature of said thermal mass.

3. The system of claim 2 wherein said thermistor is positioned approximately centrally in said thermal mass.

4. The system of claim 3 wherein said thermal mass is salt water.

5. The system of claim 4 wherein said transceiver is disposed within said container.

6. The system of claim 4 wherein said transceiver is positioned external to said container.

7. The system of claim 1 further comprising an ambient case air temperature sensor operable to measure an ambient case air temperature in said at least one refrigeration case and in communication with said transceiver.

8. The system of claim 1 further comprising a defrost termination temperature sensor operable to measure a defrost termination temperature in said at least one refrigeration case and in communication with said transceiver.

9. The system of claim 1 further comprising a temperature display module connected to an ambient temperature sensor operable to measure an ambient refrigerant temperature, a defrost termination temperature sensor operable to measure a defrost termination temperature and said simulated product temperature sensor;

said wirelessly transmitted data further including said ambient air temperature and said defrost termination temperature;

said temperature display module being in communication with said transceiver for wirelessly transmitting said data to said receiver.

10. The system of claim 1 wherein said controller is configured to include user-defined alarm limits for said wirelessly transmitted data and further comprising a remote monitoring station for remote monitoring said wirelessly transmitted data and remotely signaling said alarm limits.

11. A method for refrigeration system control, said method comprising:

setting a maximum allowable product temperature for a circuit having at least one refrigeration case;

determining a simulated product temperature for the circuit;

wirelessly transmitting said simulated product temperature from said circuit to a system controller;

calculating a difference between the simulated product temperature and the maximum allowable product temperature; and

adjusting a temperature set point of the circuit based upon the calculated difference.

12. The method as defined in claim 11 further comprising decreasing the temperature set point of the circuit if the calculated difference is greater than a first limit and increasing the temperature set point of the circuit if the calculated difference is less than a second limit.

13. The method as defined in claim 12 further comprising maintaining the temperature set point of the circuit if the calculated difference is between the first limit and the second limit.

14. The method as defined in claim 11 wherein said simulated product temperature is an average simulated product temperature based upon a plurality of simulated product temperatures taken over a predetermined period.

15. The method as defined in claim 11 further comprising the step of configuring said system controller to include user-defined alarm limits for a predetermined calculated difference between said simulated product temperature and said maximum allowable product temperature.

16. The method as defined in claim 11 further comprising the step of remotely monitoring said simulated product temperature.

17. A method for refrigeration system control, said method comprising:

measuring a first parameter from at least one refrigeration case;

wirelessly transmitting said measured first parameter to a receiver;

communicating said measured first parameter from said receiver to a controller;

electronically controlling said at least one refrigeration case to affect said measured first parameter;

measuring a second parameter from another refrigeration case;

wirelessly transmitting said measured second parameter to said receiver;

communicating said measured second parameter from said receiver to said controller;

electronically controlling said another refrigeration case to affect said measured second parameter; and

floating a circuit temperature set point based upon said measured first parameter.

18. A method for refrigeration system control, said method comprising:

measuring a first parameter from at least one refrigeration case in a first refrigeration circuit;

measuring a second parameter from at least one other refrigeration case in a second refrigeration circuit;

wirelessly transmitting said measured first parameter and said measured second parameter to a receiver;

communicating said measured first parameter and said measured second parameter to a controller;

electronically controlling said at least one refrigeration case to affect said measured first parameter;

electronically controlling said at least one other refrigeration case to affect said measured second parameter; and

floating a circuit temperature set point of at least one of said first circuit and said second circuit based upon said measured first parameter or said measured second parameter.

19. A method for refrigeration system control, said method comprising:

measuring a simulated product temperature measurement from at least one refrigeration case;

wirelessly transmitting said simulated product temperature measurement to a receiver;

communicating said simulated product temperature measurement to a controller; and

electronically controlling said at least one refrigeration case to affect said simulated product temperature measurement.

20. A method for refrigeration system control comprising:

measuring a first parameter from at least one refrigeration case;

wirelessly transmitting said measured first parameter to a receiver;

communicating said measured first parameter from said receiver to a controller; and

electronically controlling said at least one refrigeration case to affect said measured first parameter

measuring a second parameter from another refrigeration case;

wirelessly transmitting said measured second parameter to said receiver;

communicating said measured second parameter from said receiver to said controller; and

electronically controlling said another refrigeration case to affect said measured second parameter;

wherein said first parameter is a defrost termination temperature measurement of said at least one refrigeration case and said second parameter is an ambient case air temperature of said another refrigeration case.

21. A method for refrigeration system control comprising:

measuring a first parameter from at least one refrigeration case in a first refrigeration circuit;

measuring a second parameter from at least one other refrigeration case in a second refrigeration circuit;

wirelessly transmitting said measured first parameter and said measured second parameter to a receiver;

communicating said measured first parameter and said measured second parameter from said receiver to a controller;

electronically controlling said at least one refrigeration case to affect said measured first parameter; and

electronically controlling said at least one other refrigeration case to affect said measured second parameter;

wherein said first parameter is a defrost termination temperature measurement of said at least one refrigeration case and said second parameter is an ambient case air temperature of said at least one other refrigeration case.