Moisture responsive sprinkler circuit
OwnerBijan Lashgariinventor
Life of this patent
Estimating the term…
Abstract
A sprinkler circuit responds to the presence of water and limits watering accordingly. The sprinkler circuit comprises a control circuit and a moisture responsive circuit. The control circuit may be wired in series to a sprinkler cable at any point between a sprinkler controller (e.g., timer) and a sprinkler valve, and is powered by a valve signal sent from the sprinkler controller to the valve. The moisture responsive circuit includes two pairs of electrodes wired in series and residing at different depths. When resistance across both pairs of electrodes drops sufficiently, a relay in the control circuit opens and interrupts the valve signal to the valve.
Claims21
A sprinkler circuit comprising:
- a control circuit electrically connectable in series to a sprinkler cable running between a sprinkler controller and a sprinkler valve;
- and
- a moisture responsive circuit electrically connected to the control circuit, the moisture responsive circuit comprising a first pair of electrodes and a second pair of electrodes serially connected,
- wherein the control circuit is powerable by a valve signal sent from the sprinkler controller to the sprinkler valve, and wherein the control circuit is adapted to interrupt the valve signal to the sprinkler valve when both the first pair of electrodes experience water and the second pair of electrodes experience water.
An irrigation system comprising:
- at least one sprinkler valve;
- a control circuit providing a valve signal to the sprinkler valve;
- and
- a moisture responsive circuit electrically connected between a first port and a second port of the control circuit, the moisture responsive circuit including a first pair of electrodes and a second pair of electrodes serially connected between the first port and the second port, wherein a first resistance across the first pair of electrodes is reduced when the first pair of electrodes experiences water and a second resistance across the second pair of electrodes is reduced when the second pair of electrodes experiences water,
- wherein the control circuit interrupts the valve signal to the sprinkler valve when the sum of the first resistance and the second resistance is below a resistance threshold.
A method for controlling an irrigation system, the method comprising:
- serially connecting a control circuit to a sprinkler cable carrying a valve signal to a sprinkler valve;
- providing the valve signal to a rectifier and to a relay;
- rectifying the valve signal in the control circuit to generate a rectified signal;
- providing the rectified signal from the control circuit to a moisture responsive circuit;
- variably attenuating the rectified signal in the moisture responsive circuit to obtain an attenuated signal, wherein the amount of attenuation depends on the amount of water experienced by the moisture responsive circuit;
- providing the attenuated signal from the moisture responsive circuit to the relay in the control circuit, wherein the level of the attenuated signal determines if the relay is energized;
- zeroing the valve signal to the sprinkler valve if the relay is energized;
- and
- providing the valve signal to the sprinkler valve through the relay if the relay is un-energized.
Dependencies are inferred from the claim text.