Passive sensors for automatic faucets and bathroom flushers

• US 8,955,822 B2
• Filed: 10/01/2012
• Issued: 02/17/2015
• 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:
  US13/573,663
• Publication Number:
  US 20130145535A1
• Time in Patent Office: 869 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. An optical sensor for controlling a valve of an electronic faucet or bathroom flusher, comprising

an optical element located at an optical input port and arranged to partially define a detection field;

a light detector constructed to detect ambient light from said detection field; and

a control circuit for controlling opening and closing of a flow valve, said control circuit being constructed to sample periodically said light detector to receive signal from said light detector corresponding to the detected ambient light for background levels of said ambient light and present levels of said ambient light, said control circuit including a microcontroller executing a control algorithm programmed to initiate said opening and closing based on periodic data limited to the detected ambient light including

utilizing a stability value corresponding to changes of the detected ambient light within a time period and a target value corresponding to intensity of the detected ambient light with respect to background ambient light, and

determining user states corresponding to behavior of a user within said detection field wherein each said user state depends on both said stability value and said target value, wherein said controlling the opening and closing of said flow valve is based on a transition between said user states.

2. The optical sensor of claim 1 wherein said control circuit is constructed to sample periodically said detector based on the amount of previously detected light.

3. The optical sensor of claim 1 wherein said control circuit is constructed to open and close said flow valve based on first detecting arrival of a user and then detecting departure of said user.

4. The optical sensor of claim 1 wherein said control circuit is constructed to open and close said flow valve based on detecting presence of a user.

5. The optical sensor of claim 1 wherein said optical element includes an optical fiber.

6. The optical sensor of claim 1 wherein said optical element includes a lens.

7. The optical sensor of claim 1 wherein said light detector is constructed to detect light in the range of 400 nanometers to 1000 nanometers.

8. The optical sensor of claim 1 wherein said light detector is constructed to detect light in the range of 500 nanometers to 950 nanometers.

9. The optical sensor of claim 1 wherein said light detector includes a photodiode.

10. The optical sensor of claim 1 wherein said light detector includes a photoresistor.

11. A method of controlling a valve of an electronic faucet or a bathroom flusher using an optical sensor, comprising the acts of:

providing a light detector optically coupled to an optical element located at an input port partially defining a detection field, and providing a control circuit including a microcontroller;

detecting periodically ambient light arriving at said light detector from said detection field;

providing signals corresponding to said detected ambient light from said light detector to said control circuit for background levels of said ambient light and present levels of said ambient light; and

executing a control algorithm by said microcontroller programmed to initiate opening and closing of a flow valve based on periodic data limited to the detected ambient light by determining several predefined user states identifying a user initially approaching said input port and thus entering a first of said user states and progressing through a succession of said user states separated over time, wherein said opening or closing of said flow valve is initiated only after a predefined sequence of said user states.

12. The method of controlling a valve according to claim 11 wherein said control circuit is constructed to adjust a sample period based on prior detection of the ambient light.

13. The method of controlling a valve according to claim 11 wherein said several predefined user states include pairs of user states corresponding to increase and decrease of said detected ambient light.

14. The method of controlling a valve according to claim 11, wherein said detecting ambient light includes using a photodiode.

15. The method of controlling a valve according to claim 11, wherein said detecting ambient light includes using a photoresistor.

16. The method of controlling a valve according to claim 11, wherein said detecting ambient light includes detecting light in the range of 500 nanometers to 950 nanometers.

17. A method of controlling a valve of an electronic faucet or a bathroom flusher using an optical sensor, comprising

providing a light detector optically coupled to an optical element at an input port partially defining a detection field, and providing a control circuit including a microcontroller;

detecting periodically ambient light arriving at said light detector from said detection field;

providing signals corresponding to said detected ambient light from said light detector to said control circuit;

executing a control algorithm by said microcontroller programmed to initiate opening and closing of a flow valve, including

utilizing a stability value corresponding to changes of the detected ambient light within a time period and a target value corresponding to intensity of the detected ambient light with respect to background ambient light, and

determining user states corresponding to behavior of a user within said detection field wherein each said user state depends on both said stability value and said target value; and

controlling the opening and closing of said flow valve using said control circuit based on a transition between said user states, wherein said opening or closing of said flow valve is initiated only after a predefined sequence of said user states.

18. The method of controlling a valve according to claim 17 wherein said executing said control algorithm including determining a bright mode, a dark mode, and a normal mode of said light detector based on said detected ambient light.

19. The method of controlling a valve according to claim 17 wherein said control circuit is constructed to adjust a sample period based on prior detection of the ambient light.

20. The method of controlling a valve according to claim 17, wherein said detecting ambient light includes using a photodiode.

21. The method of controlling a valve according to claim 17, wherein said detecting ambient light includes using a photoresistor.

22. The method of controlling a valve according to claim 17, wherein said detecting ambient light includes detecting light in the range of 500 nanometers to 950 nanometers.