Thermal Process Control

• US 20140220197A1
• Filed: 12/23/2013
• Published: 08/07/2014
• Est. Priority Date: 12/21/2012
• Status: Active Grant

• Current Assignee: John Bean Technologies Corporation
• Original Assignee: John Bean Technologies Corporation
• Inventors: Hocker, Jon A., Strong, John R., Gunawardena, Ramesh M.
• Granted Patent: US 9,366,579 B2
• Time in Patent Office: Days
• US Class Current: 426/233
• CPC Class Codes: A22C 17/008 for measuring quality, e.g. to determine further processing
• CPC Class Codes: A23B 4/005 Preserving by heating
• CPC Class Codes: A23L 3/185 in solid state
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: B65G 15/00 Conveyors having endless load-conveying surfaces, i.e. belts and like continuous members, to which tractive effort is transmitted by means other than endless driving elements of similar configuration having load-conveying surfaces formed by interconnected longitudinal links B65G17/06
• CPC Class Codes: B65G 15/50 Endless load-carriers consisting of a series of parallel ropes or belt strips
• CPC Class Codes: B65G 2201/0202 Agricultural and processed food products
• CPC Class Codes: B65G 47/53 between conveyors which cross one another
• CPC Class Codes: G01K 1/026 arrangements for monitoring a plurality of temperatures, e.g. by multiplexing
• CPC Class Codes: G01K 1/14 Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
• CPC Class Codes: G01K 1/146 arrangements for moving thermometers to or from a measuring position
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 13/06 in linear movement
• CPC Class Codes: G01K 13/12 combined with sampling devices for measuring temperatures of samples of materials
• CPC Class Codes: G01K 2207/06 for preparation purposes
• CPC Class Codes: G01N 33/02 Food
• CPC Class Codes: G01N 33/12 Meat; fish
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence
• CPC Class Codes: G05B 2219/2621 Conveyor, transfert line

Abstract

A thermal processing and control system (10) includes a thermal processing station (12) for receiving food products (14) being carried on a conveyor system (16). A first scanning station (18) is located upstream from a similar processing station (12) for scanning the food products being carried by the conveyor (16). A second scanning station (20) is located downstream of the thermal processing station (12). A diverter conveyor (24) diverts selected food products (14) from the conveyor (16) to a transverse conveyor (26) which is capable of positioning the diverted food product onto a temperature measurement station (28), whereat the temperature of the food product is measured, either manually or automatically.

Claims

1. A method for measuring the internal temperature of discrete, thermally treated workpieces, comprising:

(a) selecting workpieces for temperature measurement from an output stream of workpieces exiting from a thermal processing system;

(b) removing selected workpieces from the output stream;

(c) dimensionally characterizing the removed selected workpieces; and

(d) measuring the temperature of the selected workpieces at one or more locations expected to give a representative temperature of the workpieces based on the results of the dimensionally characterizing the selected workpieces.

2. The method according to claim 1, wherein the selected workpieces are removed to a temperature measurement station at which the temperatures of the workpieces are measured.

3. The method according to claim 2, wherein the temperatures of the workpieces are measured using one or more probes automatically inserted into the workpieces.

4. The method according to claim 1, wherein:

the thermally treated workpieces are carried away from the thermal processing system via conveyor system; and

the selected workpieces are removed from the conveyor system and transported to a temperature measurement station by a transport method selected from the group consisting of;

(i) one or more conveyors;

(ii) gravity;

(iii) a gap or opening in the conveyor system;

(iv) pressurized air jets;

(v) multi-directional pick-and-place actuator;

and (vi) robotic arm.

5. The method according to claim 1, wherein the step of selecting workpieces from the output stream of the thermal processing system is selected from the group consisting of:

(a) random selection;

(b) sweeping across the stream of workpieces outputted from the thermal processing system;

(c) selecting the workpieces based on size; and

(d) selecting the workpieces based on one or more physical attributes.

6. The method according to claim 1, further comprising scanning the workpieces removed from the output stream and modeling one or more physical attributes of the workpieces from the results of scanning the workpieces to dimensionally characterize workpieces.

7. The method according to claim 1, wherein determining the degree of thermal treatment occurring of the workpiece comprising ascertaining if the workpiece has reached a suitable level of thermo-treatment.

8. The method according to claim 1, further comprising analyzing the temperature measurements versus the time span between the exiting of the workpieces from the thermal processing system and the measured temperature of the workpieces to determine the degree of thermo-treatment occurring of the workpiece.

9. A method for controlling a thermal processing system for food products in a thermal processing station, comprising:

(a) monitoring a stream of food products approaching a thermal processing station to determine the physical attributes and or condition, as well as the total flow rate of the food products approaching the thermal processing station, and making this data available for use by a control subsystem of the thermal processing system;

(b) monitoring the process parameters of the thermal processing system;

(c) measuring the temperatures of the food products exiting the thermal processing station, and making such temperature information available for use by the control subsystem;

(d) modeling the thermal processing system by considering one or more of the following dynamics;

(i) the manner in which changes in flow rate of the food products entering the thermal processing station results in changes to the temperature of the heat transfer fluid utilized to thermally process the food products;

(ii) the manner in which changes in the geometry of the food products entering the thermal processing station causes changes to the rate of temperature change in the food products in the thermal processing station; and

(iii) changes in the temperature of the food products exiting the thermal processing station relative to changes in the operating conditions of the thermal processing system or changes in the flow rate or the physical attributes of the food products entering the food processing station; and

(e) if the modeling results indicate that the future temperature of the food products exiting the thermal processing station is beyond a desired temperature range, the control subsystem adjusting the thermal processing system process parameters or recommending that adjustments be made to the process parameters of the thermal processing system.

10. The method according to claim 9, wherein the process parameters of the thermal processing system that may be adjusted based on the results of the modeling include a parameter selected from the group consisting of:

(i) the time that the food product spends within the thermal processing station;

(ii) the humidity of the atmosphere within the thermal processing station; and

(iii) the temperature within the thermal processing station;

(iv) the air speed within the thermal processing station;

(v) the radiation within the thermal processing station;

(vi) the activation or de-activation of a heat transfer medium to the thermal processing station; and

(vii) the activation or de-activation of heating or cooling the fluid medium used to heat or cool the thermal processing station.

11. The method according to claim 9, wherein the monitoring of the food products of the food product stream entering the thermal processing station includes scanning the food products.

12. The method according to claim 11, wherein based on the results of scanning of the food products entering the thermal processing station, diverting selected food products from the thermal processing station based on selected physical attributes of the food products.

13. The method according to claim 11, wherein based on the results of scanning of the food products entering the thermal processing station, diverting selected food products from the thermal processing station based on selected physical attributes of the food products.

14. The method according to claim 13, wherein the food products are diverted according to a physical characteristic selected from the group consisting of size, weight, shape, thickness, color, texture, condition, or appearance.

15. The method according to claim 9, wherein the step of measuring the temperatures of the food products exiting the thermal processing station comprises selecting food products from the output of the thermal processing station for temperature measurement.

16. The method according to claim 15, wherein the step of selecting food products from the food product stream exiting the thermal processing station comprising scanning the food products exiting the thermal processing station, and selecting candidate food products for temperature measurement.

17. The method according to claim 9, further comprising measuring the temperature of selected food products exiting the thermal processing station, wherein said selection of food products includes selecting by a process chosen from the group consisting of:

(a) random selection;

(b) sweeping across the stream of food products output from the thermal processing station; and

(c) selecting the work pieces based on one or more physical attributes.

18. The method according to claim 9, wherein if the monitoring of the stream of food products entering the thermal processing station has detected a changed population of the food products, or if the thermal processing control parameters have been adjusted based on the modeling results, then after one residence time of the food products in the thermal processing station, the temperature of the food products exiting the thermal processing station is measured to determine if the changes in the population of food products has caused a problem in the thermal processing station and/or if the adjustments made to the operation of the thermal processing system have timely resolved problems in the thermal processing of the food products.

19. The method according to claim 9, wherein the temperature of the food product leaving the thermal processing station is measured via probes automatically inserted into the food products.

20. The method according to claim 9, wherein the step of measuring the temperature of the food products exiting the thermal processing station includes diverting selected food products from the stream of food products exiting the thermal processing station and directing said diverted food products to a temperature measurement station.

21. A method for thermally processing a stream of food products at a thermal processing station under process parameters, comprising:

(a) selecting food products for temperature measurement from the food product stream;

(b) physically characterizing the selected food products for temperature measurement;

(c) measuring the temperature of the selected food products at one or more locations within the selected food products expected to give representative temperature of the food product; and

(d) analyzing the temperature measurement results to determine if any changes are needed in the process parameters of the thermal processing station, and if said analysis indicates that changes are needed in the process parameters of the thermal processing station, transmitting control signals to change the applicable process parameters.

22. The method of claim 21, wherein the thermal processing station is a station selected from the group consisting of a roaster, a fryer, a steamer, an oven, a proofer, a dryer, a chiller, and a freezer or similar equipment.

23. The method according to claim 21, wherein the step of selecting food products for temperature measurement includes scanning the food products and selecting specific food products for temperature measurement based on the results of the scanning.

24. The method of claim 21, wherein the step of physically characterizing the selected food products for temperature measurement includes scanning the selected food product and physically modeling the scanned food product based on the scanning results.

25. The method according to claim 21, wherein the step of measuring the temperature of the selected food products comprises automatically inserting a thermal probe into the selected food product.

26. The method according to claim 21, wherein the step of analyzing the temperature measurements of the selected food products includes determining if the workpiece has been sufficiently processed in the thermal processing station.

27. The method according to claim 26, wherein the step of determining whether the food product has been satisfactorily processed at the food processing station includes determining if the workpiece has reached a suitable degree of thermal treatment.

28. The method according to claim 21, wherein the selected food products are removed from the food product stream prior to measuring the temperature of the selected food product.

29. The method according to claim 21, wherein prior to the thermal processing, the food products are scanned and based on the results of such scanning, taking one or more steps selected from:

removing from the food product stream the food products that will not be properly thermally processed at the thermal processing station;

adjusting the process parameters of the thermal processing station;

recommending that adjustments be made to the process parameters of the thermal processing station;

halting operation of the thermal processing station; and

diverting the stream of food products from the thermal processing station.

30. The method according to claim 21, wherein the process parameters for the thermal processing station are selected from the group consisting of:

the time that the food product remains in the food processing station;

the humidity of the atmosphere in the food processing station; and

the temperature of the heat transfer medium used in the food processing station to thermally process the food products;

the volume of the food product within the food processing station;

the mass of the food product within the food processing station;

the air velocity throughout the entirety or sections of the food processing station;

the operation of the heating or cooling system used to heat or cool the heat transfer medium used in the food processing station to thermally process the food products.

31. A method for optimizing the process parameters of a thermal processing station used to process workpieces, comprising:

(a) scanning the workpieces that exit the thermal processing station;

(b) physically modeling the scanned workpieces based on the data resulting from the scanning of the workpieces;

(c) selecting workpieces for temperature measurement based on the modeling of the workpieces;

(d) measuring the temperature of the selected workpieces; and

(e) analyzing the temperature measurement results to determine if changes should be made to the process parameters of the thermal processing station.

32. The method according to claim 31 wherein the selected workpieces are removed to a temperature measurement station at which the temperatures of the workpieces are measured.

33. The method according to claim 31, wherein:

the thermally treated workpieces are carried away from the thermal processing system via conveyor system; and

the selected workpieces are removed from the conveyor system and transported to a temperature measurement station by a transport method selected from the group consisting of;

(i) one or more conveyors;

(ii) gravity;

(iii) a gap or opening in the conveyor system; and

(iv) pressurized air jets.

34. The method according to claim 31, wherein the step of selecting workpieces from the output stream of the thermal processing system comprising selecting the workpieces based on one or more physical attributes.

35. The method according to claim 31, wherein the process parameters of the thermal processing station are selected from the group consisting of:

the length of time the workpiece remains in the thermal processing station;

the humidity of the atmosphere in the thermal processing station;

the temperature of the heat transfer medium used in the thermal processing station to thermally process the workpieces;

the mass of the workpieces within the thermal processing station;

the air velocity throughout the entirety or sections of the food processing station.

36. A system for measuring the temperature of food products processed at a thermal processing station operating under process parameters, comprising:

(a) a conveyance system for conveying food products in a stream that have been processed at the thermal processing station for further processing, storage, or packaging;

(b) a diverter system to direct selected food products from the conveyance system to a temperature measuring station separate from the stream of the food products;

(c) a temperature measurement system comprising temperature measurement instrumentation for measuring the temperature of food products at the temperature measuring station; and

(d) an information transmission system for transmitting the temperature measurement data from the temperature measurement system.

37. The system according to claim 36, wherein the diverter system comprising an auxiliary conveyor system to carry the selected food products from the conveyance system to the temperature measurement station, where at the temperature measurement instrumentation is located.

38. The system according to claim 36, wherein the food products are selected for diversion from the stream of food products by one of the following:

(a) random selection;

(b) sweeping across the stream of food products output from the thermal processing station;

(c) selecting the work pieces based on one or more physical attributes.

39. The system according to claim 36, further comprising a scanner for scanning all or some of the thermally processed food products of the stream, with the scanning data generated from said scanning useable to model the physical features of the scanned food products.

40. The system according to claim 39, wherein the scanner is located either upstream or downstream from the diverter.

41. The system according to claim 36, further comprising a computing device to receive scanning data from the scanner to analyze such data for selecting food products for diversion from the stream of food products for temperature measurement.

42. The system according to claim 41, wherein the computing device receiving data from the temperature measuring instrumentation and analyzing said data to determine if changes should be made to the process parameters of the thermal processing station.

43. The system according to claim 36, further comprising an upstream scanner located upstream from the thermal processing station to scan the food products entering the thermal processing station, said upstream scanner connected in data transmission communication with a computing device to analyze the data from the upstream scanner, and based on this data, if the analysis indicates a sufficient variance between the scanning results and predetermined parameters of the food products, undertaking one or more of the following steps:

(a) sending control signals to the thermal processing station to alter the process parameters used by the thermal processing station;

(b) sending a communication to personnel regarding the variance in the parameters of the food products between the scanned parameters and the predetermined parameters;

(c) altering the operation of the thermal processing station; and

(d) diverting food products from the thermal processing station.