Electronic faucets for long-term operation

1. An electronic faucet comprising

a housing;

at least one water inlet line extending into the housing;

a water outlet from the housing, said housing including removable cover parts;

a valve cartridge located inside said housing, said valve cartridge including a solenoid valve and a diaphragm for controlling the water flow between said at least one inlet line and the outlet;

a battery located inside said housing;

an object sensor, located inside said housing, for detecting a faucet user; and

a control circuit, located inside said housing, for controlling the opening and closing of the solenoid valve, the control circuit including a microcontroller, receiving signals from the object sensor, for controlling operation of the electronic faucet and controlling a solenoid driver receiving battery power from a DC-to-DC converter, the solenoid driver providing power to the solenoid valve, said microcontroller controlling the operation by utilizing timers measuring detection and non-detection of the faucet user by the object sensor.

2. The electronic faucet of claim 1 , wherein said solenoid valve includes a latching actuator.

3. The electronic faucet of claim 1 , wherein said solenoid valve includes a non-latching actuator.

4. The electronic faucet of claim 1 , wherein said solenoid valve includes an actuator having an isolation membrane for containing fluid inside a plunger cavity of said actuator.

5. The electronic faucet of claim 1 , wherein said valve cartridge includes a filter member in the flow path between said at least one inlet line and the outlet.

6. The electronic faucet of claim 1 , including a faucet head removably mounted to the housing and being associated with the object sensor.

7. The electronic faucet of claim 1 , further including a check valve releasably retained in each inlet line.

8. The electronic faucet of claim 1 , wherein the housing includes a spout portion having a removable cover plate and enclosing a spout having a first end connected to said water outlet.

9. The electronic faucet of claim 1 , wherein said microcontroller utilizes one of said timers for controlling open time when water is flowing from the water outlet.

10. An electronic faucet mounted on a countertop, comprising

a housing including a mixing valve, a solenoid valve, a battery for providing power, and an object sensor all being located inside the housing;

a cold water inlet line and a hot water inlet line both extending into said housing and providing water to said mixing valve, said mixing valve adjusting a ratio of cold and hot water;

a water outlet for providing water mixed in said mixing valve; and

a control circuit including a microcontroller communicating with the object sensor and a solenoid driver receiving battery power and initiating the solenoid valve, said control circuit being constructed to adjust dynamically activation sensitivity of said object sensor to prevent erroneous detection of a faucet user, said microcontroller executing a self calibration routine for said object sensor.

11. The electronic faucet of claim 10 including a timer for controlling open time when water is flowing from the water outlet.

12. The electronic faucet of claim 10 including a DC-to-DC converter receiving battery power and providing signals to said microcontroller controlling said solenoid driver for opening and closing said solenoid valve.

13. The electronic faucet of claim 10 wherein said object sensor is a capacitive sensor.

14. The electronic faucet of claim 13 , wherein the control circuit includes grounded and floating capacitors and a flip-flop circuit constructed to select different sensitivity levels of the capacitive sensor.

15. The electronic faucet of claim 10 including a faucet head removably mounted to the housing.

16. The electronic faucet of claim 10 , wherein said battery is located inside a battery holder being accessible by removing a portion of the faucet housing.

17. An electronic faucet, comprising

a housing;

at least one water inlet line extending into the housing;

a water outlet from the housing;

an object sensor for detecting a faucet user;

a solenoid valve for controlling the water flow between said at least one inlet line and the outlet;

a battery; and

a control circuit including a microcontroller communicating with the object sensor, and a solenoid driver receiving battery power and initiating the solenoid valve, said control circuit being constructed to adjust dynamically activation sensitivity, at different sensitivity levels to prevent erroneous detection of the faucet user, said microcontroller executing a self calibration routine for said object sensor.

18. The electronic faucet of claim 17 , wherein said housing is mounted on a countertop and said faucet includes a mixing valve located below said countertop and constructed to adjust ratio of cold and hot water.

19. The electronic faucet of claim 17 , wherein said solenoid valve is located below a countertop.

20. The electronic faucet of claim 17 including a timer for controlling open time water when is flowing from the water outlet.

21. The electronic faucet of claim 17 including a DC-to-DC converter receiving battery power and providing signals to said microcontroller controlling said solenoid driver for opening and closing said solenoid valve.

22. The electronic faucet of claim 17 wherein said object sensor is a capacitive sensor.

23. The electronic faucet of claim 22 , wherein the control circuit includes grounded and floating capacitors and a flip-flop circuit constructed to select said sensitivity levels of the capacitive sensor.

24. The electronic faucet of claim 17 including a faucet head removably mounted to the housing.

25. The electronic faucet of claim 23 , wherein the flip-flop circuit includes a D-type flip-flop.