General Electric Company

Robert J Simcoe

Donald L Watrous

Robert C Helfrich

David C Finch

MOS circuitry conducting constant current at high voltage comprises first, second and third depletion mode MOSFETs connected in a loop, with their gates joined at the junction of the second and third MOSFETs. A control circuit is coupled to the junction of the first and second MOSFETs. The drain of an enhancement mode fourth MOSFET is connected to the junction of the second and third MOSFETs while its source remains unconnected. With high voltage applied to the junction of the first and third MOSFETs, and with the control circuit essentially nonconductive, the fourth MOSFET experiences diode breakdown, thereby acting as a high voltage source which prevents gate oxide rupture on the first, second and third MOSFETs and causing the first and second MOSFETs to become nonconductive until the control circuit is again rendered conductive.

High voltage standoff MOS driver circuitry

A room thermostatic control providing for automatic power defer, i.e. modification of load consumption of electrically energized heating and cooling systems during intervals when there is a peak load demand on the electrical supply system. During power defer ambient indoor temperature is controlled by set point adjustment to minimize discomfort, e.g. by pre-boosting, by ramped temperature deferral at controlled rates, and thereafter by ramped recovery at controlled rates to the reference, i.e. desired, temperature. The preferred embodiment has normal and night set back reference temperature potentiometers and ambient indoor temperature sensing circuits providing, respectively, analog reference and analog indoor signals. Digital set point signals are derived and compared with the analog indoor signal to actuate relays controlling operation of the heating and cooling means, e.g. compressor and auxiliary resistance heating. A circuit sensing external conditions, e.g. outdoor temperature, indicative of power defer, is utilized to generate a power defer signal for enabling modification of the set point. In the preferred embodiment digital signals are stored for each of a plurality of consecutive real time intervals for heating and cooling modes. A real time clock is utilized to access the digital signals for the current time interval. During presence of a power defer signal set point variation is controlled in accordance to the relevant digital signals for each current time interval.

System and method of power demand limiting and temperature control

An electronic sequence type controller for appliances or the like which provides numerical indications of how much time will be required to execute a program cycle which a user has selected, and how much time is remaining as an operating cycle proceeds. Additionally, means are provided for a service technician to rapidly set the controller to a particular program step for diagnostic purposes. More specifically, after user cycle options have been inputted, control logic initially enables a counting and display means to count up and rapidly executes the entire selected program a first time, the rapid first execution appearing essentially instantaneous to the user. This presets the counting and display means with a representation of the total number of program advancing operations required to execute the selected program. Next, the control logic means enables the counting and display means to count down, and executes the selected program a second time with relatively longer intervals between successive program advancing operations. The counting and display means then provides a continuous representation of the remaining time to go during the second execution. For diagnostic purposes, the control logic has a diagnostic mode wherein the program is advanced incrementally a step at a time in response to manual actuation of a switch.

Time to go and diagnostic display for electronic sequence type appliance

An electronic sequence type controller structure having a high degree of flexibility in programming the time durations of particular steps in the program. The controller which includes a digital program sequence counter capable of stepping from one state to the next in response to inputted clock pulses, each state representing a particular program step. A programmable digital counter, programmed by a timer setting control, is operable to count inputted clock pulses and to output a signal when the number of clock pulses corresponding to a programmed time duration have been inputted. A program memory is responsive to the state of the program sequence counter for directing the timer setting control to program a time duration desired for any particular program step into the programmable timer. To direct the overall operation to effect periodic program advancing operations there is provided a control logic means. In operation, the control logic means is operable to direct a clock pulse to the programmable timer for each program advancing operation in the event a signal has not been received from the programmable timer and a program step is therefore in progress. When a program step is completed, a signal is received from the programmable timer and the control logic means is then operable to direct a clock pulse to the program sequence counter to cause stepping to the next program step, whereupon the program memory directs the timer setting control to program a new time duration into the programmable timer.

Electronic appliance controller with flexible program and step duration

A cooking appliance, such as a deep fat fryer, includes programmable control system which monitors the operation of the cooking appliance and enables appropriate actions at proper times. The system includes a microcomputer which implements various timing and control functions. Control switches select operational states of the appliance. A diode matrix allows selection of input data. A multiplex circuit interconnects input signals to the microcomputer, a monitor circuit turns off the appliance if multiplexing stops. A temperature control circuit generates a signal responsive to the cooking fluid temperature and compares it with various reference signals under control of the microcomputer. A cooking control circuit generates a voltage proportional to the cooking fluid temperature, modifies it according to the desired doneness of the food being cooked, and converts it to a current which charges the capacitor in an oscillator. The oscillator provides a series of pulses which vary in frequency as the temperature of the fluid varies. These pulses are multiplexed to the microcomputer. Output circuits connect the microcomputer to various contactors controlling operation of the appliance and to indicators, such as lights and a buzzer. The control system provides a low energy melt state and a cooking state with energy input suitable for cooking food. It signals when a load of food is done. Additionally it enables signals when unwanted temperature conditions exist and turns off heat when temperature goes outside set limits.

Growing community of inventors

Liverpool, NY, United States of America

Robert J Simcoe