Auto-water shut-off for an external door water dispenser

1. A refrigerator, comprising:

a cabinet defining a food-storage compartment;

a door pivotally mounted to the cabinet to provide selective access to the food-storage compartment;

a liquid dispensing unit accessible at an exterior surface of the door comprising:

a receptacle support;

a dispensing system comprising an electrically-operated valve, the dispensing system being configured to dispense a liquid into a receptacle on the receptacle support;

a sensor system comprising:

a first capacitive sensor; and

a second capacitive sensor;

a control unit electrically coupled to the dispensing system and electrically coupled to the sensor system,

wherein the control unit is configured to operate the first capacitive sensor to determine a receptacle height relative to a reference, and is configured to operate the second capacitive sensor to determine an instantaneous liquid height, relative to the reference, of a liquid contained within the receptacle, and is configured to operate the electrically-operated valve based on the receptacle height and the instantaneous liquid height, and

wherein at least one of the capacitive sensors is configured to produce an electrostatic field and detect one or more changes thereto based on entry into the electrostatic field by the receptacle.

2. The refrigerator of claim 1 , wherein:

the control unit is configured to operate the electrically-operated valve such that liquid is dispensed into the receptacle until the instantaneous liquid height is a specified difference from the receptacle height.

3. The refrigerator of claim 2 , further comprising a user interface,

wherein the user interface is configured to allow a user to select the specified difference as a desired liquid height as a percentage of the receptacle height.

4. The refrigerator of claim 1 , wherein:

the reference is a location of the receptacle support.

5. The refrigerator of claim 1 , wherein:

the reference is a location of the first sensor or the second sensor.

6. The refrigerator of claim 1 , wherein:

the control unit is configured to operate the first capacitive sensor to determine an uppermost part of the receptacle as the receptacle height.

7. The refrigerator of claim 1 , wherein:

the control unit is configured to operate the sensor system to determine a stale liquid contained in the receptacle.

8. The refrigerator of claim 1 , further comprising a user interface electrically coupled to the control unit,

wherein the user interface is configured to present the instantaneous liquid height relative to the receptacle height of a liquid contained within the receptacle.

9. The refrigerator of claim 1 , further comprising a user interface comprising

at least one sound producing device,

wherein the sound producing device is configured to alert a user when the receptacle is full.

10. A method of dispensing a liquid from a refrigerator, comprising the steps of:

sensing, by a first capacitive sensor, an uppermost receptacle height of a top of a receptacle relative to a reference;

dispensing a liquid into the receptacle;

sensing, by a second capacitive sensor, an instantaneous liquid height of a liquid contained within the receptacle relative to the reference;

comparing the instantaneous height of the liquid within the receptacle with a height of the receptacle to determine if the liquid height is a specified difference from the receptacle height;

repeating the steps of sensing the instantaneous height of the liquid within the receptacle and comparing the instantaneous height of the liquid within the receptacle with the height of the receptacle; and

terminating the dispensing when the liquid height is a specified difference from the height of the receptacle,

wherein at least one of the capacitive sensors is configured to produce an electrostatic field and detect one or more changes thereto based on entry into the electrostatic field by the receptacle.

11. The method of claim 10 , wherein the reference is a location of a first sensor or second sensor.

12. The method of claim 10 , further comprising the steps of:

illuminating at least one visual indicator to indicate a stale liquid found in the receptacle.

13. The method of claim 10 , further comprising the steps of:

producing an audible tone when terminating the dispensing of liquid.

14. The method of claim 10 , further comprising the steps of:

displaying the instantaneous height of the liquid within the receptacle relative to the height of the receptacle.

15. The method of claim 10 , wherein the reference is a location of a receptacle support on which the receptacle is located during the dispensing.

16. The method of claim 10 , further comprising the steps of:

determining the specified difference based on a selected fill percentage.

17. A refrigerator, comprising:

a cabinet defining a food-storage compartment;

a door pivotally mounted to the cabinet to provide selective access to the food-storage compartment;

a liquid dispensing unit accessible at an exterior surface of the door comprising:

a receptacle support;

a dispensing system comprising an electrically-operated valve, the dispensing system being configured to dispense a liquid into a receptacle on the receptacle support;

a sensor system comprising:

a first capacitive sensor, the first capacitive sensor is disposed offset from a center of the receptacle support; and

a second capacitive sensor;

a control unit electrically coupled to the dispensing system and electrically coupled to the sensor system,

wherein the control unit is configured to operate the first capacitive sensor to determine a receptacle height relative to a reference, and is configured to operate the second capacitive sensor to determine an instantaneous liquid height, relative to the reference, of a liquid contained within the receptacle, and is configured to operate the electrically-operated valve based on the receptacle height and the instantaneous liquid height.