Passive sensors for automatic faucets

• US 8,276,878 B2
• Filed: 06/05/2010
• Issued: 10/02/2012
• Est. Priority Date: 12/04/2002
• Status: Expired due to Term

• Current Assignee: Sloan Valve Company
• Original Assignee: Sloan Valve Company
• Inventors: Parsons, Natan E., Guler, Fatih, Herbert, Kay, Mo, Xiaoxiong, Wu, Haiou, Zhang, Yue
• Primary Examiner(s): Fristoe, Jr., John K
• Assistant Examiner(s): JELLETT, MATTHEW WILLIAM
• Application Number:
  US12/802,396
• Publication Number:
  US 20100327197A1
• Time in Patent Office: 850 Days
• Field of Search: 251/129.04, 430/2, 430/4, 431/3, 462/3, 4DI/G 3
• US Class Current: 251/129.04
• CPC Class Codes: E03C 1/057 touchless, i.e. using sensors
• CPC Class Codes: E03D 5/105 touchless, e.g. using sensors

Abstract

The present invention is directed to novel optical sensors and novel methods for sensing optical radiation. The novel optical sensors and the novel optical sensing methods are used, for example, for controlling the operation of automatic faucets and flushers. The novel sensors and flow controllers (including control electronics and valves) require only small amounts of electrical power for sensing users of bathroom facilities, and thus enable battery operation for many years. A passive optical sensor includes a light detector sensitive to ambient (room) light for controlling the operation of automatic faucets or automatic bathroom flushers.

Claims

1. A sensor-based faucet system, comprising:

a faucet body including a water conduit having at least one inlet for receiving water and at least one outlet for providing water;

an optical sensor for generating sensor output signals provided to an electronic control circuit including a microcontroller providing a control signal to a power consumption controller operatively coupled to a voltage regulator;

an aerator for receiving water from said outlet, said sensor being associated with a sensor port located at least partially in said aerator; and

a battery providing electrical power; and

a main valve controlled by an actuator constructed to receive control signals from said electronic control circuit for switching between an open state of said valve and a closed state of said valve;

said open state permitting water flow, and said closed state of said valve preventing water flow from said outlet.

2. The sensor-based faucet system of claim 1 wherein said sensor is an optical sensor optically coupled to said sensor port by an optical fiber.

3. The sensor-based faucet system of claim 1 further including a leak detector constructed to detect water flow from said inlet to said outlet in said closed state.

4. The sensor-based faucet system of claim 3 wherein said leak detector includes at least two electrodes and an electrical circuit for measuring an electrical property between said electrodes and thereby detecting water flow between said inlet and said outlet.

5. The sensor-based faucet system of claim 1 wherein said main valve, said battery, and said control circuit are located in said faucet body.

6. The sensor-based faucet system of claim 1 wherein said main valve, said battery, and said control circuit are located outside of said faucet body.

7. A sensor-based automatic faucet system, comprising:

a faucet body including a water conduit having at least one inlet for receiving water and at least one outlet for providing water to an aerator;

an optical detector constructed to detect ambient light;

a control circuit, including a microcontroller, arranged to control operation of said optical sensor, and

a main valve controlled by an actuator receiving control signals from said control circuit for switching between an open state of said valve and a closed state of said valve;

said open state permitting water flow, and a closed state of said valve preventing fluid flow from said outlet;

said control circuit being constructed to receive periodically signal from said optical detector corresponding to the detected ambient light and to control said opening and closing by executing a detection algorithm employing detection of increases of said ambient light due to the presence of a user said detection algorithm also employing detection of decreases of said ambient light due to the presence of said user, wherein decision about said open state and said closed state is based on detection of increases and decreases of said ambient light.

9. The sensor-based automatic faucet system of claim 7 including an optical element optically coupled to said optical detector, said optical element located at an optical input port and arranged to partially define a detection field having a selected size and orientation that eliminate invalid targets.

10. The sensor-based automatic faucet system of claim 9 wherein said control circuit is constructed to execute a calibration routine that accounts for size and orientation of said detection field by said optical element.

11. The sensor-based automatic faucet system of claim 7 wherein said control circuit is constructed to sample periodically said detector based on the amount of previously detected light.

12. The sensor-based automatic faucet system of claim 9 wherein said optical element includes an optical fiber.

13. The sensor-based automatic faucet system of claim 7 wherein said light detector includes a photodiode.

14. The sensor-based automatic faucet system of claim 7 wherein said light detector includes a photoresistor.

15. The sensor-based automatic faucet system of claim 7 wherein said light detector is constructed to detect light in the range of 400 to 1000 nanometers.

16. The sensor-based automatic faucet system of claim 7 wherein said light detector is constructed to detect light in the range of 500 to 950 nanometers.

17. The sensor-based automatic faucet system of claim 7 wherein said optical element includes a lens.

18. The sensor-based automatic faucet system of claim 9 wherein said optical element includes an array of slits.

19. The sensor-based automatic faucet system of claim 7 further including a leak detector constructed to detect water flow from said inlet to said outlet in said closed state.

20. The sensor-based automatic faucet system of claim 19 wherein said leak detector includes at least two electrodes and an electrical circuit for measuring an electrical property between said electrodes and thereby detecting water flow between said inlet and said outlet.

25. The sensor-based faucet system of claim 7 wherein said main valve and said control circuit are located in said faucet body.

26. The sensor-based faucet system of claim 7 wherein said main valve and said control circuit are located outside of said faucet body.

8. An optical sensor for an electronic faucet, comprising

an optical input port arranged to receive infrared radiation;

an optical detector optically coupled to said input port and constructed to detect ambient light;

a battery providing electrical power; and

a control circuit for controlling opening and closing of a faucet valve, said control circuit includes a microcontroller and a power consumption controller, said microcontroller provides a control signal to said power consumption controller operatively coupled to a voltage regulator controlling voltage provided to a solenoid driver;

said control circuit being constructed to receive periodically detector signal from said optical detector based on said detected ambient light, and said microcontroller executing a control algorithm processing detection of increases of said ambient light due to the presence of a user, said detection algorithm also employing detection of decreases of said ambient light due to the presence of said user, and providing control signals for said solenoid driver opening and closing said faucet valve, wherein decision is based on detection of increases and decreases of said ambient light.

21. The optical sensor of claim 8 wherein said light detector is constructed to detect light in the range of 400 to 1000 nanometers.

22. The optical sensor of claim 8 wherein said light detector is constructed to detect light in the range of 500 to 950 nanometers.

23. The optical sensor of claim 8 wherein said light detector includes a photodiode.

24. The optical sensor of claim 8 wherein said control circuit is constructed to operate said light detector at a reduced sensing rate in dark room conditions.