SENSOR DEVICE FOR USE IN CONTROLLING IRRIGATION

• US 20120229284A1
• Filed: 05/23/2012
• Published: 09/13/2012
• Est. Priority Date: 06/20/2006
• Status: Active Grant

• Current Assignee: Rain Bird Corporation
• Original Assignee: Rain Bird Corporation
• Inventors: Hern, Randall A., Fern, David G., Peterson, Gerald E., Redmond, David M.
• Granted Patent: US 8,733,165 B2
• Time in Patent Office: Days
• US Class Current: 340/618
• CPC Class Codes: A01G 25/167 Control by humidity of the soil itself or of devices simulating soil or of the atmosphere; Soil humidity sensors
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01W 1/14 Rainfall or precipitation gauges measuring volume in general G01F

Abstract

Methods and apparatus are provided herein for sensing rain fall for use in irrigation control. In one embodiment, a wireless rain sensor comprises a housing at least partially covering a first sensor, a controller and a wireless transmitter. The first sensor comprises a moisture absorptive material located to be contacted by rain fall and configured to expand in response to the contact with the rain fall and contract in response to an absence of the rain fall. The controller is coupled to the first sensor and configured to output signals corresponding to a variable amount of expansion and contraction of the moisture absorptive material. The wireless transmitter is configured to transmit wireless signals, at least one wireless signal comprising data corresponding to the variable amount of expansion and contraction of the moisture absorptive material.

Claims

1. A rain sensor comprising:

a moisture absorptive material configured to move in response to rain fall;

a plunger configured to move in response to and proportional to the movement of the moisture absorptive material;

a sensor element comprising;

a first element; and

a second element coupled to the plunger and configured to move with the plunger relative to the first element causing a change in a variable corresponding to the amount of rain; and

a controller configured to measure the variable and further configured to generate a signal comprising an indication of the amount of rain fall based on the variable.

2. The rain sensor of claim 1, wherein the first element is fixed in a location.

3. The rain sensor of claim 1, wherein the indication comprises the variable.

4. The rain sensor of claim 1, wherein the indication comprises a value representing the amount of rain fall generated based on the variable.

5. The rain sensor of claim 1, wherein the first element is a resistive element, and wherein the second element is a wiper in contact with the resistive element, and wherein the variable comprises resistance.

6. The rain sensor of claim 5, wherein the resistive element is fixed in a location, and wherein the wiper is moving.

7. The rain sensor of claim 1, wherein the first element is a first electrode and the second element is a second electrode and wherein the variable comprises a capacitance.

8. The rain sensor of claim 7, wherein the first electrode is fixed in a location, and wherein the second electrode is moving.

9. The rain sensor of claim 7, wherein an insulating material is located between the first electrode and the second electrode.

10. The rain sensor of claim 1, wherein the controller further comprises a transceiver configured to wirelessly transmit the signal to a remote device and further configured to receive at least a second signal from the remote device.

11. The rain sensor of claim 1, further comprising a temperature sensor wherein the signal further comprises the second indication.

12. The rain sensor of claim 1, wherein the moisture absorptive material comprises a plurality of hygroscopic disks.

13. The rain sensor of claim 1, wherein the sensor unit is further configured to determine a signal strength of the signal.

14. The rain sensor of claim 13, wherein the sensor unit further comprises an indicator configured to display the determined signal strength.

15. The rain sensor of claim 14, wherein the indicator comprises an LED configured to display the signal strength by flashing a predetermined number of times, the number of flashes indicating the signal strength.

16. The rain sensor of claim 14, further comprising a power source configured to supply power to the sensor unit.

17. A wireless rain sensor comprising:

a housing at least partially covering a first sensor, a controller and a wireless transmitter;

the first sensor comprising a moisture absorptive material located to be contacted by rain fall and configured to expand in response to the contact with the rain fall and contract in response to an absence of the rain fall;

the controller coupled to the first sensor and configured to output signals corresponding to a variable amount of expansion and contraction of the moisture absorptive material; and

the wireless transmitter configured to transmit wireless signals, at least one wireless signal comprising data corresponding to the variable amount of expansion and contraction of the moisture absorptive material.

18. The wireless rain sensor of claim 17, wherein the moisture absorptive material comprises a plurality of hygroscopic material disks.

19. The wireless rain sensor of claim 17, further comprising a temperature sensor at least partially covered by the housing,

wherein the controller is coupled to the temperature sensor and configured to output signals corresponding to a variable air temperature;

wherein the at least one wireless signal comprises additional data corresponding to the variable air temperature.

20. The wireless rain sensor of claim 17 wherein the wireless transmitter transmits wireless signals comprising the data corresponding to the variable amount of expansion of the moisture absorptive material independent of the variable amount of expansion of the moisture absorptive material.

21. The wireless rain sensor of claim 17 wherein the wireless transmitter transmits wireless signals comprising the data corresponding to the variable amount of expansion of the moisture absorptive material independent of a rain fall threshold.

22. The wireless rain sensor of claim 17 wherein there is no rain fall threshold set at the wireless rain sensor.

23. The wireless rain sensor of claim 17 wherein the first sensor further comprises a component coupled to a first portion of the moisture absorptive material and configured to move with the expansion and contraction of the moisture absorptive material.

24. The wireless rain sensor of claim 23 wherein a second portion of the moisture absorptive material is fixed such that the moisture absorptive material expands in a direction away from the second portion and the component moves in the direction away from the second portion.

25. The wireless rain sensor of claim 23 wherein the first portion of the moisture absorptive material is opposite the second portion.

26. The wireless rain sensor of claim 23 wherein the first sensor further comprises a spring fixed at one end and coupled at a second end to the component, wherein the spring is configured to cause the component to apply biasing pressure on the moisture absorptive material against expansion of the moisture absorptive material.

27. The wireless rain sensor of claim 23 wherein the first sensor further comprises:

a first element;

a second element coupled to the component and configured to move with the component and relative to the first element causing a change in a variable corresponding to the amount of rain; and

wherein the controller is configured to measure the variable, the variable corresponding to the amount if expansion and contraction of the moisture absorptive material.

28. A method of sensing rain fall comprising:

sensing, with a first sensor, a variable amount of expansion and contraction of a moisture absorptive material located to be contacted by rain fall, the moisture absorptive material configured to expand in response to contact with the rain fall and contract in response to an absence of the rain fall;

outputting, with a controller, signaling corresponding to the variable amount of the expansion and contraction of the moisture absorptive material; and

transmitting wireless signals with a wireless transmitter, at least one wireless signal comprising data corresponding to the variable amount of expansion and contraction of the moisture absorptive material, wherein the first sensor, the controller and the wireless transmitter are at least partially covered by a housing.

29. A wireless rain sensor comprising:

a housing at least partially covering a first sensor, a controller and a wireless transmitter;

the first sensor comprising;

a moisture absorptive material located to be contacted by rain fall and configured to expand in response to the contact with the rain fall and contract in response to an absence of the rain fall; and

a component coupled to a first portion of the moisture absorptive material and configured to move with the expansion and contraction of the moisture absorptive material;

the controller coupled to the first sensor and configured to output signals corresponding to a variable amount of expansion and contraction of the moisture absorptive material; and

the wireless transmitter configured to transmit wireless signals independent of a rain fall threshold, at least one wireless signal comprising data corresponding to the variable amount of expansion and contraction of the moisture absorptive material,

wherein the rain fall threshold is not set at the wireless rain sensor.