A CONTROL SYSTEM FOR COOKING APPARATUS

Abstract: The invention relates to a control system for cooking apparatus which includes a programmed digital microcomputer responsive to a plurality of user selectable product keys individually capable of setting the cooking temperature at individually selected values and the cooking times at individually selected values.

Description: Technical field to which the invention relates This invention relates to a control system for cooking apparatus comprising means having a plurality of different cooking cycle programs to control a cooking process, means for selecting a cooking cycle program to cook a product with the program, means responsive to a selected program for attempting to set a parameter other than cooking time of the apparatus at a selected value in accordance with said selected program, means for storing timing information relating to the cooking process and means for determining whether the cooking process is complete. Description of the Prior Art U. S. Patent 4,437,159 relates to a cooking computer for use with a deep fat fryer and having a temperature sensing probe. Up to ten recipes, each of which includes a cooking time and a time-temperature adjustment factor for adjusting cooking time as a function of temperature during a cook cycle, can be stored in a microcomputer. Cooking times and time compensation factors stored in recipes are user alterable through a keyboard. Such a cooking computer is not capable of automatically shifting a temperature control setpoint when selecting a product and starting a cook cycle. From GB-A-2 155 662 a deep fryer cooker controller is known which controls essentially all aspects of the cooking process and includes a number of features which enhance the flexibility of the system. In particular, it includes a microcomputer associated with a memory capable of storing up to six cooking cycle programs, each program having up to eight different time and temperature set points. Technical Problem It is an object of the present invention to provide a new and improved control system for cooking apparatus which avoids one or more of the disadvantages of prior such control systems. Solution of the Technical Problem The above problem is solved by the combination of the following features: means coupled to said attempting means for determining whether said parameter has already been set at said selected value by a previously selected program in the apparatus; first register means coupled to said determining means for setting said parameter at said selected value, if it has not already been so set; means for interrupting said selected program if the parameter has already been set by another previously selected program and is not within a predetermined operating range of said selected value of the parameter as attempted to be set; means for proceeding with the balance of said selected program, if the parameter is within said predetermined operating range of said selected value of the parameter; second register means responsive to said selected program for storing timing information relating to the cooking process; means responsive to said second register means for decrementing said second register means as the cooking process continues; and means responsive to said second register means for determining whether the cooking process is complete. Advantageous Effects of the invention The invention provides a new and improved control system for cooking apparatus in which a user selectable product key is capable of setting the cooking temperature if the cooking temperature has not been set at the selected value elsewhere in the apparatus. The invention also provides a new and improved control system for cooking apparatus which is capable of automatically shifting the temperature of the cooking apparatus if the temperature set elsewhere in the apparatus has not been set at a newly selected value corresponding to a newly selected product. Still, the invention provides a new and improved control system for cooking apparatus which is capable of setting a parameter if the parameter has been set elsewhere at other than a newly selected value. Brief Description of the Drawings Fig.1 is a perspective view of a fryer including a control system constructed in accordance with the invention; Fig.2 represents apparatus including a microcomputer and usable in connection with a control system constructed in accordance with the invention; and Fig.3 is a flow chart comprising a representation of a portion of a microcomputer which operates according to a computer program produced according to the flow chart. Before referring to the drawings in detail, it will be understood that for purposes of clarity, the apparatus represented in block diagrams in Figs.2 and 3 utilizes, for example, an analog-to-digital converter and a microprocessor which includes such hardware as a central processing unit, program and random access memories, timing and control circuitry, input-output interface devices and other conventional digital subsystems necessary to the operation of the central processing unit as is well understood by those skilled in the art. The microprocessor operates according to the computer program produced according to the flow chart represented in the drawings. Referring now more particularly to Fig.1 of the drawings, there is represented cooking apparatus 10 comprising, for example, a fryer 11 having a movable product basket 12 operated by a gear and motor train 13 for movement into and out of the cooking medium such as shortening in the fryer 11. The frying apparatus 11 has an oil drain pipe 14 connected to a drain valve 15 in a filter unit 16. The filter unit preferably comprises papers and chemicals for filtering the cooking oil. A pump 17 is provided for returning the oil to the cooking apparatus via a pipe 18. A control panel 20 having a display screen 20a in a header assembly 21 is connected to a control including a microcomputer in the header assembly for operating the control. Referring now more particularly to Fig.2 of the drawings, the microcomputer 22 includes a central processing unit which receives an input from the keybord 23 which may, for example, comprise a capacitive keyboard. The control includes a conventional power supply 24, a reset circuit 25 for resetting the microcomputer when renewing power in the power supply, a clock oscillator 26 for providing clock pulses to the microcomputer 22, a temperature sensor circuit 27 for sensing the temperature within the cooking apparatus, an audible alarm 28, an alpha/numeric display 29 and indicator lights 30. The apparatus also includes an input status circuit 31 which may, for example, be responsive to a door switch and to the open/close condition of the drain valve. The microcomputer controls an output relay circuit 32 which may, for example, control the gas valves of a burner or heating element or microwave or other heating means. Considering now the programmed microcomputer with reference to the flow chart of Fig.3, the control system for cooking apparatus includes means 35 for optionally selecting a program subroutine 36 for programming the microcomputer to control a cooking process utilizing a cooking medium, for example, shortening or cooking oil. The selecting means 35 preferably comprises an "optional enter" portion 35 which may, for example, be a product cycle key, such as, a chicken cycle key. The control system also includes means 37 for attempting to set a parameter other than cooking time at a selected value in accordance with the optionally selected subroutine. The parameter may, for example, be the temperature of the cooking medium sensed by a temperature sensing probe of the temperature sensor circuit 27, or the parameter may, for example, be level, pressure or humidity. The control system also includes means 38 coupled to the attempting means for determining whether the parameter has been set at a selected value elsewhere in the apparatus. The means 38 comprises a "is parameter set elsewhere at selected value ?" microprocessor portion. The control system also includes first register means 39 coupled to the determining means 38 for setting the parameter at the selected value. More particularly, the first register means comprises a "set parameter register" microprocessor portion coupled to the "no" output of the means 38. The control system also includes means 40 for proceeding with the balance of the optionally selected subroutine. The means 40 comprises a "proceed with balance of subroutine" microprocessor portion coupled to the output of the "set parameter" register microprocessor portion 39. The control system also includes second register means 41 responsive to the optionally selected subroutine for storing timing information relating to the cooking process, for example, the total cooking time for a product. The second register means 41 comprises a "load register" microprocessor portion coupled to the microprocessor portion 40. When the "load register" microprocessor portion 40 is loaded, the cooking process for the selected product begins. The "load register" microprocessor portion 40 output is coupled to a status display 42 which may, for example, provide audio and visual outputs. For example, the display may indicate an operator prompt or alarm message. The control system also includes means 43 responsive to the second register means 41 for decrementing the register means 41 as the cooking process continues. The means 43 comprise a "decrement register" microprocessor portion 43. The control system also includes means 44 responsive to the register means 41 for determining whether the cooking process is complete. The means 44 comprises a "is process complete ?" microprocessor portion. The "no" output of the microprocessor portion 44 is coupled to the "decrement register" microprocessor portion 43 to continue the decrementing of the register microprocessor portion 41 until the cooking process is complete. The microprocessor portion 44 has a "yes" output coupled to a status display 45 which may, for example, display the word"done"indicating that the cooking process is complete. The display may also, for example, take the form of an audio signal. The decrementing of the register microprocessor portion 41 by the "decrement register" microprocessor portion 43 may be done by, for example, a timer or a complex cooking computer program function. The status display microprocessor portion 45 is coupled to the "optional enter" microprocessor portion 35 to terminate the program subroutine cooking process. The control system also includes second means 46 for determining whether the parameter set at the selected value elsewhere is operating within a predetermined operating range of the selected value of the parameter as attempted to be set by a microprocessor portion 37. The second means 46 comprises a "is parameter set at the second value elsewhere operating within a predetermined operating range of the selected value of the parameter as attempted to be set ?" coupled to the "yes" output of the microprocessor portion 38. A "proceed" microprocessor portion 47 is coupled to the "yes" output of the microprocessor portion 46. The apparatus also includes means 47,48 responsive to the second determining means 46 for continuing with the balance of the subroutine. The "proceed" microprocessor portion 47 is coupled to a "skip set parameter, continue with balance of subroutine" microprocessor portion 48. The microprocessor portion 48 is coupled to the "load register" microprocessor portion 41. The "no" output of the "is parameter set at selected value elsewhere within range of selected value attempted to be set ?" microprocessor portion 46 is coupled to a "stop" microprocessor portion 49. The "stop" microprocessor portion 49 is coupled to the "optional enter" microprocessor portion 35 to terminate the program subroutine. The control system also includes a plurality of additional portions similar to those just described from the "optional enter" key 35 through the "stop" microprocessor portion 49. A portion of another channel similar to that just described is represented in Fig.3 with similar portions having similar reference numerals primed to represent the coupling between the "set parameter" register 39′ microprocessor portion and the "is parameter set at selected value ?" microprocessor portion 38. While there has been described what is at present considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, aimed to cover all such changes and modifications as fall within the true spirit and scope of the invention.

Claims: A control system for cooking apparatus, comprising: a) means having a plurality of different cooking cycle programs to control a cooking process; b) means for selecting a cooking cycle program to cook a product with the program; c) means responsive to a selected program for attempting to set a parameter other than cooking time of the apparatus at a selected value in accordance with said selected program; d) means for storing timing information relating to the cooking process; and e) means for determining whether the cooking process is complete; characterized by: f) means (38) coupled to said attempting means for determining whether said parameter has already been set at said selected value by a previously selected program in the apparatus; g) first register means (39) coupled to said determining means (38) for setting said parameter at said selected value, if it has not already been so set; h) means for interrupting said selected program if the parameter has already been set by another previously selected program and is not within a predetermined operating range of said selected value of the parameter as attempted to be set; i) means (40) for proceeding with the balance of said selected program, if the parameter is within said predetermined operating range of said selected value of the parameter; j) second register means (41) responsive to said selected program for storing timing information relating to the cooking process; k) means (43) responsive to said second register means for decrementing said second register means as the cooking process continues; and l) means (44) responsive to said second register means (41) for determining whether the cooking process is complete. A control system in accordance with claim 1, characterized in that said means (35) for selecting a cooking cycle program comprises means for individually selecting individual programs for individual selected products, and which control system includes a plurality of means individually responsive to said individual selected programs for attempting to set a parameter of the apparatus at a selected value in accordance with said individual selected programs, and a plurality of means individually coupled to said attempting means for determining whether said parameter has been set at said selected value by a previously selected program in the apparatus. A control system in accordance with claim 1, characterized in that said apparatus includes a cooking medium and said parameter is the temperature of said cooking medium. A control system in accordance with claim 3, characterized in that it includes means for displaying the temperature of said medium. A control system in accordance with claim 1, characterized in that it includes means for displaying the status of said parameter.

Inventors: SCHREYER, WILLIAM M.
Applicants: FOOD AUTOMATION-SERVICE TECHNIQUES, INC. A CORPORATION OF THE STATE OF DELAWARE
Application year: 1987
Main classification: G05D23
IPC codes: A47J27, G05D23, A47J37