AU600181B2 - Stir prompt apparatus - Google Patents

Description

i COMMONWEALTH OF AUSTRALIA FORM PATENTS ACT 1952 S P FTFT. F C A T I O N Cr M P T. T P FOR OFFICE USE: Class Int.Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: 400 Priority: Related Art: a a 0 J4 p1 v '-"'4ii Name of Applicant: FOOD AUTOMATION-SERVICE TECHNIQUES, INC.

Q 0 "Address of Applicant: 905 Honeyspot Road, Stratford, Connecticut 06497, United States of America ,Actual Inventor: Mario Pasquini, and Kathie A. Breen .'oAddress for Service: SHELSTON WATERS, 55 Clarence Street, Sydney Complete Specification for the Invention entitled: "STIR PROMPT APPARATUS" The following statement is a full description of this invention, including the best method of performing it known to us:- 1 This invention relates to apparatus for prompting an operator to stir a cooking medium in a cooking appliance and more particularly, to such apparatus which is useful in connection with commercial fryers which are customarily used in fast food restaurants where solid shortening may be used and the heating elements are not evenly distributed throughout the shortening in the fryer.

Due to the uneven distribution of heating elements, shortening can remain solid. Pieces of solid shortening which detach can alter the ability of the fryer to control the temperature reliably. This can result in an improperly cooked product, thereby affecting quality.

This problem occurs most often in electric fryers, although it also can occur in, for example, gas fryers.

The procedure for eliminating this problem is to stir the shortening vigorously during a cold start-up.

Our invention is directed to apparatus which prompts the operator to stir the shortening and can insure that the stirring is done at the appropriate time.

It is an object of the present invention, therefore, to provide a new and improved apparatus for prompting an operator to stir a cooking medium in a cooking appliance which avoids one or more of the disadvantages of prior cooking apparatus.

It is another object of the invention to provide a new and improved apparatus for prompting an operator to stir a cooking medium in a cooking appliance during a cold start-up of the cooling appliance.

2 It is another object of the invention to provide a new and improved apparatus for prompting an operator to stir a cooking medium in a cooking appliance for a predetermined number of times.

It is another object of the invention to provide a new and improved apparatus for prompting an operator to stir a cooking medium in a cooking appliance in which the prompting can be cancelled: It is another object of the invention to provide a new and improved apparatus for prompting an operator to stir a cooking a medium in a cooking appliance in which a the difference in temperature between a plurality of temperature probes at different locations in the cooking .a medium is used to prompt the operator.

0 aIn accordance with the invention, apparatus for 00 0 Sprompting an operator to stir a cooking medium in a cooking appliance comprises means for determining whether the temperature of a cooking medium is below a 0000 predetermined valued below which it is desired to prompt an operator to stir the cooking medium. The apparatus 004t also includes register means responsive to the temperature-determining means when the temperature of the ,0 cooking medium is below the predetermined value for 0000 determining the number to times stirring is to be 0 4 performed. The apparatus also includes timer means responsive to the temperature-determining means for determining a predetermined time interval between stir prompt signals to be initialized. The apparatus also 3 includes means responsive to the register means for determining whether the number of times stirring is to be performed equals zero. The apparatus also includes decrementing means responsive to the timer means for decrementing the register means when the timer means has timed the predetermined time interval and stirring is to be performed. The apparatus also includes means responsive to the decrementing means for initializing a stir prompt signal to an operator to stir the cooking medium. The apparatus also includes means responsive to the initializing means for rendering a stir prompt signal. The apparatus also includes means for initializing a cancellation of the stir prompt signal when actuated. The apparatus also includes means responsive to the cancellation-initializing means for determining whether the cancellation-initializing means has been actuated. The apparatus also includes means responsive to the actuation of the cancellation-initializing means for cancelling the stir prompt signal.

Preferably, the apparatus includes second timer means and means responsive to the decrementing means for initializing a stir prompt signal to an operator to stir the cooking medium and for starting the second timer AM means. Furthermore, the apparatus preferably includes means responsive to the second timer means after a second predetermined time interval for cancelling the stir prompt signal.

Preferably also, the apparatus includes means 4 @AL~4

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responsive to the second timer means for determining whether the temperature differential of the cooking medium at different locations in the cooking medium is less than a predetermined value at or above which is desired to prompt an operator to stir the cooking medium. This preference also includes means responsive to either the second timer means after a second predetermined time interval or to the temperature-differential-determining means when the temperature differential is less than a predetermined value for cancelling the stir prompt signal.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description, taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

Referring now to the drawings: Fig. 1 is a schematic diagram including a portion of a cooking appliance and apparatus constructed in accordance with the invention for prompting an operator to stir a cooking medium in the cooking appliance; Fig. 2 is a flow-chart comprising a schematic representation of a portion of the Fig. 1 apparatus which operates according to a computer program produced according to the invention; Fig. 3 is a flow-chart comprising a schematic representation of a portion of Fig. 1 apparatus which operates according to a computer program produced according to the invention; 5 Fig. 4 is a flow-chart comprising a schematic representation of a portion of the Fig. 1 apparatus which operates according to a computer program produced according to the invention; Fig. 5 is a flow-chart comprising a schematic representation of a portion of the Fig. 1 apparatus which operates according to a computer program produced according to the invention; Fig. 6 is a flow-chart comprising a schematic representation of a portion of the Fig. 1 apparatus which operates according to a computer program produced according to the invention; Before referring to the drawings in detail, it will be understood that for purposes of clarity, the apparatus represented in the block diagrams of Figs, 1-6, inclusive, utilize, 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 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 corresponding computer program produced according to the corresponding flow-chart represented in the drawings.

Apparatus constructed in accordance with the invention for prompting an operator to stir a cooking medium in a cooking appliance may be useful in a cooking 6 appliance such as described in copending application Serial No. 937,988, filed December 4, 1986 which describes a commercial fryer and describes and claims cooking apparatus. The stir prompt apparatus of the present invention comprises means for determining whether the temperature of a cooking medium is below a predetermined value below which it is desired to prompt an operator to stir the cooking medium. This means comprises, for example, a temperature sensor circuit including, for example, a temperature sensing probe disposed in the cooking medium, for example, shortening. A cooking computer useful in the stir prompt apparatus is represented in Fig. 1.

Referring now more particularly to Fig. 1, a microcomputer 10 includes a central processing unit which receives an input from a keyboard 11 which may, for example, comprise a capacitive keyboard. The apparatus of Fig. 1 includes a conventional power supply 12, a reset circuit 13 for resetting the microcomputer when renewing power in the power supply, a clock oscillator 14 for providing clock pulses to the microcomputer 10, a temperature sensor circuit 15 for sensing the temperature within the cooking apparatus, an audible alarm 16, an alpha-numeric display 17 and indicator lights 18. The apparatus also includes an input status circuit 19 which may, for example, be responsive to a door switch (not shown) and to the open/close position of a drain valve (not shown). The microcomputer controls an output relay 7 i circuit 20 which may, for example, control the electric heating elements or gas valves of a burner or other heating means 21. The apparatus also includes a communication port 22 for transmitting signals to and from other apparatus.

The temperature sensor circuit may comprise a single temperature-sensing probe or may, in some embodiments, comprise two or more temperature-sensing probes at different locations in the cooking medium for providing signals representing the temneratures at different locations in the cooking medium. The microprocessor may then include means for determining the temperature differential of the cooking medium at different locations in the cooking medium.

Referring now to Fig. 2, there is represented a top level flow chart for the stir program which shows the entry to and exit from the stir program. The microcomputer 10 is programmed in accordance with selected ones of the flow charts of Figs. 2-6, inclusive. The microcomputer 10 has a "power on" microprocessor portion which actuates an "initialization" microprocessor portion 31 which conditions the means for determining 4whether the temperature of a cooking medium is below a predetermined value below which it is desired to prompt an operator to stir the cooking medium. This means also comprises an "is temperature less than melt cycle limit?" microprocessor portion 32. At this time the fryer is in a melt cycle or mode wherein the shortening can be melted.

8 i;r o -urri;- r.rilwx-a _li The "no" output of the microprocessor portion 32 is coupled to a "fryer enters normal cook cycle mode" microprocessor portion 33 which is; in turn, coupled in an idle loop to the input of microprocessor portion 32.

The "yes" output of the microprocessor portion 32 is coupled to a "jump to stir program" microprocessor portion 34. The microprocessor 10 also includes a "return from stir program" microprocessor portion 35 which is coupled to one of the selected flow charts of Figs. 3-6, inclusive, as will be more fully explained subsequently.

The microprocessor portion 35 is coupled to the input of the microprocessor portion 33.

Referring now to Figs. 2 and 3 of the drawings, Fig.

3 represents a flow chart for a stir program based on timer expiration for initiating a stir alarm and display and manual cancellation of the stir alarm and display.

The "jump to stir program" microprocessor portion 34 of Fig. 1 may be coupled to the "stir program" microprocessor portion 36 of Fig. 3. The microcomputer includes register means responsive to the temperature-determining means when the temperature of the cooking medium is below the predetermined value for determining the number of times stirring is to be performed. The microprocessor portion 36 is coupled to a "x equals number of times to perform stir routine" microprocessor portion 37.

The microcomputer also includes timer means responsive to the temperature-determining means for determining the time interval between stir prompt signals -9to be initialized. The microprocessor portion 37 is coupled to an "initialize timer, t" microprocessor portion 38 which is coupled to an "is x equal to zero?" microprocessor portion 39. The "no" output of the microprocessor portion 39 is coupled to an "is t equal to zero?" microprocessor portion 40. Timer means responsive to the temperature-determining means for determining a predetermined time interval between stir prompt signals to be initialized comprises the microprocessor portion The "no" output of the microprocessor portion 40 is coupled in a loop to the input of the microprocessor portion 40 so that the timer continues to count down until t equals zero.

The microcomputer also includes decrementing means responsive to the timer means for decrementing the register means when the timer means has timed the predetermined time interval and stirring is to be performed. The decrementing means comprises a "decrement microprocessor portion 41.

The microcomputer also includes means responsive to the decrementing means for initializing a stir prompt signal to an operator to stir the cooking medium. The output of the microprocessor portion 41 is coupled to a "display and alarm are initialized" microprocessor portion 42. The microprocessor portion 42 is coupled to an "alarm on" microprocessor portion 43. The apparatus includes means responsive to the initializing means for rendering a stir prompt signal. Thus, the microprocessor portion 43 10 controls the alarm signal 16 and the alpha-numeric display 17 of Fig. 2.

The apparatus also includes means for initializing a cancellation of the stir prompt signal when actuated.

This means may comprise an alarm cancel key which is manually actuated. The alarm cancel key is preferably at the fryer so that the operator is prompted to go to the vat and press the alarm cancel key and to stir the fryer vat vigorously. The apparatus also includes means responsive to the cancellation-initializing means for determining whether the cancellation-initializing means has been actuated. The microprocessor portion 43 is coupled to a "has alarm cancel key been pressed?" microprocessor portion 44. The "no" output of the microprocessor portion 44 is coupled in an idle loop to the input of the microprocessor portion 43.

The apparatus also includes means responsive to the actuation of the cancellation-initializing means for cancelling the stir prompt signal. The "yes" output of the microprocessor portion 44 is coupled to a "cancel stir alarm and display" microprocessor portion 45 which is coupled to the input of the "initialize timer, t" microprocessor portion 38 to re-initialize the timer, t.

SThe loop is repeated x times. When x 0, the stir program is terminated and control returns to the top level flow chart (Fig. The "yes" output of the "is x equal to zero?" microprocessor portion 49 is coupled to a "return to top level flow chart" microprocessor portion 46.

11 -ql~f-r* OTi I 4-4 _l o000 *a o000 0 o 0 0 ooo ooo a o w o ao 0 0 00 o 0 0400 0000 0 40 0 00 W 0 0* B000 00 00 0 40* 0 04 5 r0 0O r9 b 6 Referring now to Fig. 4, Fig. 4 represents a flow-chart for a stir program based on timer expiration, and automatic cancellation of stir alarm and display. The "jump to stir program" microprocessor portion 34 of Fig. 1 may be coupled to the "stir program" microprocessor portion 25 of Fig. 4. The microprocessor portions 37, 38, 39, 40, 41 and 46 may be the same as corresponding microprocessor portions represented in Fig. 3 and, accordingly, will not be described again.

To effect automatic cancellation of the stir alarm and display, the Fig. 4 apparatus includes second timer means and means responsive to the decrementing means for initializing a stir prompt signal to an operator to stir the cooking medium and for starting the second timer means. The "decrement x" microprocessor portion 41 is coupled to a "display and alarm are initialized; start timer, t microprocessor portion 47. The Fig. 4 apparatus also includes means responsive to the initializing means for rendering a stir prompt signal before the elapse of a second predetermined time interval. The microprocessor portion 47 is coupled to a "is t equal to zero?" microprocessor portion 48. The "no" output of the microprocessor portion 48 is coupled to an "alarm on" microprocessor portion 49. The microprocessor portion 49 controls the alarm signal 16 and the alpha-numeric display 17 of Fig. 2. The "no" output of the "alarm on" microprocessor portion 49 is coupled in a loop to the input of microprocessor portion 48. The 12 apparatus also includes means responsive to the second timer means after a second predetermined time interval for cancelling the stir prompt signal, for example, when the second timer means reaches zero. The "yes" output of the microprocessor portion 48 is coupled to a "cancel stir alarm and display" microprocessor portion 50. The output of the microprocessor portion 50 is coupled to the input of the microprocessor portion 38.

If the operator responds to the alarm quickly and stirs vigorously for several seconds, the shortening temperature is at a much lower temperature after being stirred than it was prior to the stir. The shortening temperature differential can be used to cancel the alarm before the time expires, as will be described in connection with Fig. Referring now to Fig. 5, Fig. 5 is a flow-chart for a stir program based on timer expiration, and an autcmatic cancellation of alarm and display when a temperature drop is detected or a timer expires. The "jump to stir program" microprocessor portion 34 of Fig. 1 may be coupled to the "stir program" microprocessor portion 51 of Fig. 4. The microprocessor portions 37, 38, 39, 40, 41, 46, 47, 48, 49 may be the same as corresponding microprocessor portions represented in fig. 4 and, accordingly, will not be described again.

The Fig. 5 apparatus includes means responsive to the second timer means for determining whether the temperature of the cooking medium has decreased by a predetermined 13 amount. The means responsive to the second timer means is responsive to either the second timer means and after the second predetermined time interval or to the temperature-determining means when the temperature has decreased by a predetermined amount of cancelling the stir prompt signal. The "alarm on" microprocessor portion 49 is coupled to a "has temperature dropped by y degrees?" microprocessor portion 52. The "no" output of the microprocessor portion 52 is coupled in a loop to the input of the microprocessor portion 48. The "yes" output of the microprocessor portion 52 and the "yes" output of the microprocessor portion 48 are coupled to the "cancel stir alarm and display" microprocessor portion In connection with the stir program based on timer expiration, and manual cancellation of stir alarm and display (Fig. a timer is utilized to initiate the stir program. Any number of stir alarms can be sounded at specified time intervals. The operator preferably is required to press a key on the computer to cancel this alarm prior to stirring.

With a stir program based on timer expiration, and automatic cancellation of stir alarm and display based on timer expiration (Fig. a timer is utilized to initiate the stir program. Any number of stir alarms can be sounded at specified time intervals. The alarm and display will automatically be cancelled at the alarm timer expiration. The operator has been alerted that a stir time has been reached.

14 With a stir program based on timer expiration, and automatic cancellation of stir alarm and display based on timer expiration or temperature drop (Fig. a timer is utilized to initiate the stir program. Any number of stir alarms can be sounded at specified time intervals. The alarm and display will automatically be cancelled if a specified temperature drop is sensed prior to the alarm timer expiration. If a temperature decrease is not detected, the alarm timer expiration will cancel the alarm. Vigorously stirring the shortening for several 00o" seconds will cause a temperature differential that can be 4000 used to override the automatic timer cancellation.

00 t Referring now the Fig. 6, Fig 6 is a flow-chart for a stir program using the shortening temperature differential 0 as measured by two probes of apparatus 15 placed a predetermined distance apart in the fryer vat. The Fig. 6 flow-chart is based on timer expiration, with automatic 00 00 cancellation of the display and alarm based on timer 0000 expiration or temperature differential between the two 040 probes. The "jump to stir program" microprocessor portion 34 of Fig. 1 may be coupled to the "stir program" d ,"microprocessor portion 90 of Fig. 6. The microprocessor 0000 O' portions 37, 38, 39, 40, 41, 46, 47, 48, 49, 50 may be the same as corresponding microprocessor portions represented in Fig. 5 and, accordingly will not be described again.

The Fig. 6 apparatus includes means 91 responsive to the second timer means t for determining whether the temperature differential of the cooking medium at the temperature differential of the cooking medium at the 15 II probes has decreased to less than a predetermined differential Dts. The means 91 responsive to the second timer means is responsive to either the second timer means after the second predetermined time interval or to the temperature differential-determining means when the temperature differential has decreased to less than a predetermined differential Dts for cancelling the stir prompt signal. The "alarm on" microprocessor portion 49 is coupled to an "is temperature differential less than Dts?" microprocessor portion 91. The "no" output of the microprocessor portion 91 is coupled in a loop to the input of the microprocessor portion 48. The "yes" output o0 of the microprocessor portion 91 and the "yes" output of 0 1 0 00the microprocessor portion 48 are coupled to the "cancel 08 stir alarm and display" microprocessor portion This apparatus utilizes a timer to initiate the stir program. Any number of stir alarms can be sounded at *0 1 co specified timer intervals. The alarm and display will .4 automatically cancel if a specified decrease in 44 0 420 temperature differential, Dts, is sensed between the measured temperature differential and the programmed 4• temperature differential prior to the alarm timer 04 4 expiration. If a temperature differential decrease is not detected, the alarm timer expiration will cancel the alarm. Vigorously stirring the shortening for several seconds will cause a temperature differential decrease that can be used to override the automatic cancel.

While there have been described what are at present 16 considered to be the preferred embodiments of this invention, it will be obvious to this 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.

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Claims (7)

1. 2. Apparatus in accordance with claim 1 wherein said decrementing means decrements said register means when said timer means reaches zero.
2. 3. Apparatus in accordance with claim 1 or claim 2 0 including a second timer means started by means responsive to said decrementing means for initializing a cancellation of a stir prompt signal after a second predetermined time interval.
3. 4. Apparatus in accordance with claim 3 which includes means responsive to said initializing means for rendering a stir prompt signal before the elapse of a second predetermined time interval. Apparatus in accordance with claims 3 or claim 4 in 'U which said means responsive to said second timer means cancels the stir prompt signal when said second timer means reaches zero.
4. 6. Apparatus in accordance with any one of claims 3 to including: means responsive to said second timer means for determining whether the temperature of the cooking medium has decreased by a predetermined amount; and wherein said means responsive to said second timer means is 19 AI responsive also to said means for determining whether said temperature of the cooking medium has decreased by a predetermined amount for cancelling the stir prompt signal.
5. 7. Apparatus in accordance with claim 3 comprising: means for determining the temperature differential of the cooking medium at different locations in the cooking medium; means responsive to said temperature-differential- determining means and to said second timer means for determining whether the temperature differential of the cooking medium at different locations in the cooking medium is less than a predetermined value at or above which it is desired to prompt an operator to stir the cooking medium; and .i means responsive to either said second timer means after a second predetermined time interval or to said temperature-differential-determining means when said temperature differential is less than said predetermined value for cancelling the stir prompt signal.
6. 8. Apparatus in accordance with any one of the preceding claims, in which said determining means responsive to said first timer means is responsive thereto when the number of times stirring is to be performed is not equal to zero.
7. 9. Apparatus for prompting an operator to stir a cooking medium in a cooking appliance substantially as herein described with reference to the accompanying drawings. DATED this 24th day of APRIL, 1990 FOOD AUTOMATION-SERVICE TECHNIQUES, INC. Attorney: LEON K. ALLEN Fellow Institute of Patent Attorneys of Australia of SHELSTON WATERS 20