Detection of a plunger position in an irrigation control device
First Claim
1. An irrigation valve control apparatus comprising:
- a solenoid configured to cooperate with a plunger and to receive a plunger drive signal from plunger activation circuitry, wherein the plunger drive signal is configured to induce a magnetic field relative to the solenoid that causes the plunger to change positions between open and closed positions;
an input stimulus source coupled with the solenoid and configured to apply an input stimulus into the solenoid at a time while the plunger drive signal is not being applied to the solenoid, wherein the input stimulus is sufficiently small that the input stimulus applied to the solenoid does not cause the plunger to move from a current position;
sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid in response to applying the input stimulus to the solenoid; and
control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to;
determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements; and
determine one of a plurality of positions that are in between the open and closed positions based on a sequential application of multiple input stimulus signals.
1 Assignment
0 Petitions
Accused Products
Abstract
Some embodiments provide irrigation valve control apparatuses comprising: a solenoid configured to cooperate with a plunger; an input stimulus source coupled with the solenoid and configured to apply an input stimulus while a plunger drive signal is not being applied and that is sufficiently small to not cause the plunger to move; sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid; and control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements.
63 Citations
27 Claims
-
1. An irrigation valve control apparatus comprising:
-
a solenoid configured to cooperate with a plunger and to receive a plunger drive signal from plunger activation circuitry, wherein the plunger drive signal is configured to induce a magnetic field relative to the solenoid that causes the plunger to change positions between open and closed positions; an input stimulus source coupled with the solenoid and configured to apply an input stimulus into the solenoid at a time while the plunger drive signal is not being applied to the solenoid, wherein the input stimulus is sufficiently small that the input stimulus applied to the solenoid does not cause the plunger to move from a current position; sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid in response to applying the input stimulus to the solenoid; and control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to; determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements; and determine one of a plurality of positions that are in between the open and closed positions based on a sequential application of multiple input stimulus signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. An irrigation apparatus, comprising:
-
a solenoid configured to cooperate with a plunger and to receive a plunger drive signal from plunger activation circuitry wherein the plunger drive signal is configured to induce a magnetic field relative to the solenoid that causes the plunger to change positions between open and closed positions causing an opening and closing of an irrigation valve; first switching circuitry cooperated with the solenoid, wherein the first switching circuitry is configured, upon activation, to dictate a direction of electrical current flow through the solenoid, wherein the direction of current flow while the plunger drive signal is applied controls a direction of movement of the plunger in response to the application of the plunger drive signal; an input stimulus source cooperated with the solenoid, wherein the input stimulus source is configured to generate an input stimulus that is applied to a first terminal of the solenoid at a time while the plunger drive signal is not being applied to the solenoid, and wherein the input stimulus does not cause the plunger to change from a current position; a resistive load cooperated with a second terminal of the solenoid; sampling circuitry coupled with the resistive load, wherein the sampling circuitry is configured to measure one or more voltage measurements across the resistive load in response to the input stimulus; and control circuitry coupled with the sampling circuitry, wherein the control circuitry is configured to receive the one or more voltage measurements, determine a current passing through the resistive load as a function of the one or more voltage measurements, calculate an estimated inductance of the solenoid as a function of the determined current and a timing of the input stimulus, determine whether the plunger is in one of the open position and the closed position as a function of the estimated inductance of the solenoid, and determine one of a plurality of positions that are in between the open and closed positions based on a sequential application of multiple input stimulus signals.
-
-
26. An irrigation valve control apparatus comprising:
-
a solenoid configured to cooperate with a plunger and to receive a plunger drive signal from plunger activation circuitry, wherein the plunger drive signal is configured to induce a magnetic field relative to the solenoid that causes the plunger to change positions between open and closed positions resulting in opening or closing a valve such that water is allowed to pass through the valve when the plunger is in the open position and water is prevented from passing the valve when the plunger is in the closed position; control circuitry cooperated with the solenoid and configured to direct the plunger drive signal into the solenoid to induce movement of the plunger; an input stimulus source cooperated with the solenoid and configured to apply an input stimulus into the solenoid at a time while the plunger drive signal is not being applied to the solenoid, wherein the input stimulus that is sufficiently small that the input stimulus does not cause the plunger to move from a current position; and a resonant circuit comprising the solenoid, wherein the resonant circuit is coupled with the input stimulus source and configured to be excited by the input stimulus to generate a resonant response that resonates when the plunger is in one of the open position and the closed position; wherein the control circuitry is configured to determine whether the resonant response is generated in response to the input stimulus, and to determine whether the plunger is in one of the open and closed positions in response to whether the resonant response is generated, and wherein the input stimulus comprises a first resonant frequency of a plurality of resonant frequencies, and wherein the input stimulus source is further configured to apply into the solenoid a second input stimulus comprising a second resonant frequency of the plurality of resonant frequencies at a second time.
-
-
27. An irrigation valve control apparatus comprising:
-
a solenoid configured to cooperate with a plunger and to receive a plunger drive signal from plunger activation circuitry, wherein the plunger drive signal is configured to induce a magnetic field relative to the solenoid that causes the plunger to change positions between open and closed positions; an input stimulus source coupled with the solenoid and configured to apply a first input stimulus into the solenoid at a time while the plunger drive signal is not being applied to the solenoid, wherein the first input stimulus is sufficiently small that the first input stimulus applied to the solenoid does not cause the plunger to move from a current position, and wherein the first input stimulus comprises a first resonant frequency of a plurality of resonant frequencies, and wherein the input stimulus source is further configured to apply into the solenoid a second input stimulus comprising a second resonant frequency of the plurality of resonant frequencies at a second time; sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid in response to applying the first input stimulus to the solenoid; and control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements.
-
Specification