Device for Controlling a Coffee Maker

• US 20140005834A1
• Filed: 06/12/2013
• Published: 01/02/2014
• Est. Priority Date: 06/13/2012
• Status: Active Grant

• Current Assignee: Ronald J. Hoffman
• Original Assignee: Ronald J. Hoffman
• Inventors: Hoffman, Ronald J.
• Granted Patent: US 9,606,522 B2
• Time in Patent Office: Days
• US Class Current: 700/275
• CPC Class Codes: A47J 31/52 Alarm-clock-controlled mechanisms for coffee- or tea-making apparatus ; Timers for coffee- or tea-making apparatus; Electronic control devices for coffee- or tea-making apparatus
• CPC Class Codes: A47J 31/5253 of temperature
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence

Abstract

A control module suitable for controlling a manual switch type automatic drip coffeemaker (ADC) enabling the addition of fully automatic brewing start, programmable brewing strengths, programmable heater levels for keeping the coffee warm after the brewing cycle is complete, programmable shut-off time periods, automatic cleaning detector, automatic self cleaning cycle with automatic shut-off, and programmable twelve hour AM/PM or twenty-four hour time format. The control module contains a micro-controller, application specific firmware, a keypad, a liquid crystal display, a control relay, a current or a voltage sensor, indicator LED'"'"'s, a piezo audible alarm, and power supply components.

Claims

1. A coffee maker controller for controlling the operation of an electric coffee maker, the electric coffee maker being configured to be powered by an AC power source and having an electrically powered heater operatively connected in series with a power switch, a thermostat, and a thermal fuse, said coffee maker controller comprising:

a programmable microcontroller controlled by programmable logic, said programmable microcontroller having initializable memory variables, stored program values and settable user programmable time and user operating systems;

a power supply electrically connected to said microcontroller for powering said microcontroller;

an output relay interconnecting said programmable microcontroller and power supply;

said programmable microcontroller having an algorithm for controlling the operation of said programmable microcontroller;

said algorithm evaluating the state of said coffeemaker thermostat status to operate said output relay;

a switching device electronically connected to said programmable microcontroller for selecting the operating state and for setting the user programmable operating settings;

an LCD display electronically connected to said programmable microcontroller for displaying the time and user selected operating settings;

a sensor device selected from the group consisting of a voltage sensing device for sensing voltage across the electrically powered heater and a current sensing device connectable in series with the electrically powered heater for detecting current through the heater, said sensor device being electrically connected to said microcontroller to switch the operating mode of the said microcontroller according to the output of said sensor; and

an AC plug electrically connected to said power supply, said sensor device and said output relay for conveying electrical power to said power supply, said sensor and said output relay upon being plugged into an AC power receptacle.

2. A coffee maker controller according to claim 1 wherein said sensor device is selected from the group consisting of a voltage sensor and a current sensor.

3. A coffee maker controller according to claim 2 wherein said sensor device is a current sensor, said current sensor being selected from the group consisting of a Hall-effect sensor coil connected in series with the output relay;

a Hall-effect sensor with magnetic coil having enamelled copper wire wound around a ferric iron wire, said magnetic coil having a gap to induce a magnetic field through said Hall-effect sensor;

a resistive shunt connected in series with the output relay; and

a current transformer primary in series with the output relay.

4. A coffee maker controller according to claim 1 for being connected to sense the open or closed status of the thermostat, the thermostat having an open status for being open for a time period t_w, said sensor device sensing when t_w is less than a specified length of time and sending a timing signal to said algorithm in said programmable microcontroller, said microcontroller transmitting a signal to said LED display to effect a recognizable optical signal indicating the coffee maker requires cleaning, and said programmable microcontroller monitoring said output relay in an ON condition for a predetermined WARM state time period.

5. A coffee maker controller according to claim 4, the coffee maker having an electrically actuable pump with an ON and OFF switch and thermostat, and said programmable microcontroller being electrically connected to said switch, wherein a user of the coffee maker can fill the coffee maker with an acidic solution in response to said recognizable optical signal and can manually initiate an automatic cleaning signal, and said algorithm alternatively generating ON and OFF signals to said output relay, and to said ON-OFF switch and thermostat of the pump to pump the acidic cleaning solution through the coffee maker to dissolve the mineral scale deposits;

and said microcontroller being functional with respect to said ON-OFF switch of the pump in response to a manually operated control or in response to the opening of the thermostat to end the cleaning cycle.

6. A coffee maker controller according to claim 1 wherein the coffee maker has a heater, and said coffee maker controller includes a duty cycle power switch device connectable to the heater for setting the power to the heater according to the formula:

P_FL=P_FULL×

(FL_ont/FL_tp)=P_FULL×

[1−

((FL_tp−

least time period)/(FL_tp×

(NL−

1))×

(FL−

1))]

where

P_FL=power per flavor setting,

P_FULL=full power of heater,

FL_ont=flavor level power switch ON time

FL_tp=arbitrarily set time period

NL=number of flavor levels

FL=flavor level setting=power setting arbitrarily set to a user'"'"'s desired flavor of the coffee.

7. A coffee maker controller according to claim 1 wherein the coffee maker has a heater, and said coffee maker controller includes a power switch device connectable to the heater for setting the keep-warm power to the heater according to the formula:

P_KWC=P_FULL×

(t_on/t_calc)=P_FULL×

(t_on/(t_w×

NHL/HLS))

where

P_FULL=full power of heater,

P_KWC=keep warm controlled power,

t_on=the thermostat ON time in keep warm state,

t_w=normal thermostat OFF time in keep warm state,

t_calc=calculated OFF time for power switch device,

NHL=number of heater levels, and

HLS=heater level selected.

8. A coffee maker controller according to claim 1 and further comprising an LED display device electrically connected to and controlled by said programmable controller for selectively indicating the state of the electric coffee maker.

9. A coffee maker controller according to claim 1 and further including an annunciator electronically connected to said programmable microcontroller.

10. A control device for controlling the operation of an electric automatic drip coffee maker having a power switch, a heater, a thermal fuse, a thermostat having a thermostat status and being connected in series with the heater for terminating electricity to the heater if the temperature of the heater exceeds a predetermined threshold, said control device comprising:

a power controller for being supplied by an AC power source, said power controller being settable with user settings to a desired output and being programmable by a programmable logic;

said power controller comprising;

a power switch for selectively supplying power from the AC power source to the electric automatic drip coffeemaker;

a sensor for sensing the status of the thermostat of the coffee maker, said sensor being selected from the group consisting of a current sensor and a voltage sensor;

a display device showing the time of day and user settings;

an input switching device for operating said control device and programming user settings into said power controller; and

a control apparatus for inputting the thermostat status into said power controller, and control algorithms for evaluating said thermostat status to operate the power controller.

11. A control device according to claim 10 wherein said sensor is a current sensor, and said current sensor is a Hall-effect sensor with magnetic coil, said magnetic coil comprising an enameled copper wire wound upon a ferric iron wire;

said magnetic coil having a gap to induce a magnetic field through said Hall-effect sensor.

12. A control device according to claim 10 wherein the thermostat has an open time period, t_w, and a closed time period, wherein in response to the open time period t_w being greater than a specified length of time, the control algorithm calculates a relay OFF time, t_calc, that is equal to the thermostat open time, t_w, times the Number of Heater Levels, NHL, divided by the Heater Level Selected, HLS, by the user, given by the formula:

t_calc=t_w*(NHL/HLS); and

said power switch OFF time reducing the power to said coffee maker in the WARM state.

13. A control device according to claim 10 wherein the thermostat has an open time period t_w and a closed time period, and wherein said display device is actuated to indicate that the coffee maker requires cleaning in response to the thermostat open time t_w being less than a predetermined length of time, and said control device maintains said power switch in the ON condition for the remaining WARM state time period.

14. A control device according to claim 10 wherein the coffee maker can be cleaned by filling the coffee maker with an acidic cleaning agent, and said power controller is manually operable to initiate the automatic cleaning cycle;

said power controller initiating said cleaning cycle to provide brief ON and extended OFF times to slowly pump acidic cleaning agent through the coffee maker and dissolving mineral scale deposits; and

said cleaning cycle ending by a selected one of a manual command or the direction by said controller of an open thermostat.

15. A control device according to claim 10 wherein said control algorithms include an algorithm by duty cycle limiting of the power to the heater to control the brew strength of the coffee and said power level is manually set according to the formula:

P_av=P_FULL*[T_on/T_period]=P_FULL*(% min*(1−

(FL/FL_max)+(FL/FL_max)),

wherein P_av is average power, P_FULL is full power of the heater, T_on is the ON time of the power switch, and T_period is the chosen duty cycle time % min is the decimal value for the minimum ON time percentage of the period time, FL is the flavor level setting, and FL_max is the maximum number of flavor settings.

16. A control device according to claim 10 wherein said power controller further includes a display device actuable to indicate the control state of said control device.

17. A control device according to claim 10 and further including an audible annunciator device to indicate a change of a control state of said control device.