Display arrangement for cooking appliance with power control using heater energy counter

• US 4,604,518 A
• Filed: 11/16/1984
• Issued: 08/05/1986
• Est. Priority Date: 11/16/1984
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Payne, Thomas R.
• Primary Examiner(s): Paschall, M. H.
• Application Number:
  US06/672,300
• Time in Patent Office: 627 Days
• Field of Search: 219/497, 219/483, 219/486, 219/506, 219/501, 219/492, 219/453, 219/441, 307/39, 307/41, 307/38, 340/589, 340/588, 340/585
• US Class Current: 219/506
• CPC Class Codes: F24C 7/087 of electric circuits regulating heat
• CPC Class Codes: G05D 23/1951 with control of the working time of a temperature controlling device

Abstract

A display arrangement for a cooking appliance using a heater energy counter based power control system which provides a user discernible signal signifying that the appliance heating element has reached the steady state temperature associated with the user selected power setting. The heater energy counter is selectively incremented or decremented at a rate in accordance with the selected power setting such that the count rate is approximately proportional to the rate of increase or decrease respectively of the temperature of the heating element for the power setting selected. When so incremented and decremented the count of the counter provides an approximation of the actual heating element temperature. The display arrangement generates a user discernible signal when the count of the heater energy counter indicates that the associated heating element has approximately reached the steady state temperature for the selected power setting. In the illustrative embodiment the display comprises an LED array associated with each heating element. Each array is energized to provide a pattern representative of the power setting selected by the user for its associated heating element. When the count of the heater energy counter indicates that the steady state temperature for the selected setting has been reached, the display flickers for a predetermined period to signify to the user that the steady state condition has been reached.

Claims

1. An arrangement for monitoring and displaying the approximate temperature of a resistive heating element adapted for selective energization by a power signal from an external power supply at one of a plurality of power levels in response to selection by an operator of one of a plurality of power settings ranging from relatively low power settings, including an OFF setting, to relatively high power settings and displaying to the user that the element has reached the steady state power level associated with the selected power setting;

the heating element having a temperature response characterized by a transient heat-up phase followed by a steady state phase when the power setting is changed from OFF to some power setting; and

by a transient cool-down phase when the power setting is changed from a relatively higher power setting to a relatively lower power setting, the monitor and display arrangement comprising;

energy counter means for approximately tracking the heating element temperature;

counter control means operative to selectively increment said energy counter means at an increment rate which is approximately proportional to the rate of increase of the heating element temperature during the heat-up phase when operated at the selected power level, and to discontinue incrementing said energy counter means when said count at least equals a predetermined maximum count which is approximately proportional to the steady state heating element temperature for the selected power setting;

said counter control means being further operative to decrement said energy counter means when the power setting selection is changed from a relatively higher power setting to a relatively lower power setting at a decrement rate which is approximately proportional to the rate of decrease of the heating element temperature during its cool-down phase, and to discontinue decrementing said energy counter means when said count is less than a predetermined maximum count which is approximately proportional to the steady state operating temperature of the heating element at the selected relatively lower power setting; and

display means responsive to said counter control means operative to signify to the user that said count of said energy counter is closely approaching said predetermined maximum count for the selected power setting;

said display means comprising an array of display segmensts adapted to be selectively energized to form a plurality of patterns, each pattern representing a corresponding power setting, and circuit means for selectively energizing said display segments in that one of said plurality of patterns corresponding to the selected power setting, and means for intermittently interrupting energization of said display segments thereby creating a blinking effect during a period of predetermined duration, said period being initiated upon the occurrence of a predetermined count of said counter means, which count is a function of said predetermined maximum count for the selected power setting whereby blinking of said segments of said display means indicates to the user that the heating element has reached its steady state temperature for the selected power setting.

2. An arrangement for monitoring the approximate temperature of a resistive heating element adapted for selective energization by a power signal from an external power supply at one of a plurality of different power levels in response to selection by an operator of one of a plurality of power settings ranging from relatively low power settings, including an OFF setting, to relatively high power settings and displaying to the user that the heating element temperature approximately equals the steady state temperature corresponding to the selected power setting, the heating element having a temperature response characterized by a transient heat-up phase followed by a steady state phase when the power setting is changed from one relatively low lower setting including OFF to some relatively higher power setting;

and by a transient cool-down phase when the power setting is changed form a relatively higher power setting to a relatively lower power setting, the arrangement comprising;

energy counter means for approximately tracking the heating element temperature;

counter control means operative to selectively increment said energy counter means at one of a plurality of increment rates, each of which is approximately proportional to the rate of increase of the heating element temperature during the heat-up phase when operated at a corresponding power level, said one increment rate being selected according to the selected power setting;

discontinue incrementing said energy counter means when said count at least equals a selected one of a plurality of predetermined maximum counts each of which is approximately proportional to the steady state heating element temperature for corresponding power settings, said selected one maximum count being selected according to the selected power setting;

decrement said energy counter means when the selected power setting is changed from a relatively higher power setting to a relatively lower power setting at one of a plurality of predetermined decrement rates, each of which is approximately proportional to the rate of decrease of the heating element temperature during the cool-down phase as the heating element temperature decreases from a relatively high operating temperature asaociated with the previously selected higher power setting to the relatively lower steady state operating temperature associated with the selected lower power setting; and

discontinue decrementing said energy counter means when said count is less than that one of said predetermined maximum counts corresponding to the lower power setting; and

indicator means responsive to said counter control means operative to indicate to the user that said count of said energy counter means is within a predetermined range of said predetermined maximum count corresponding to the selected power setting, said indicator means comprising an array of display segments adapted to be selectively energized to form a plurality of patterns, each pattern representing a corresponding power setting, and circuit means for selectively continuously energizing said display segments to form the pattern corresponding to the selected power setting upon selection of a power setting by the user;

said circuit means further including means for intermittently interrupting energization of said display segments, thereby creating a blinking effect during a period of predetermined relatively short duration immediately following the occurrence of a predetermined count of said energy counter indicative of said heating element reaching its steady state temperature for the selected power setting. whereby the blinking of said pattern of display segments signifies to the user that the heating element temperature has approximately reached its steady state temperature for the selected power setting.