Irrigation controller with analog data input devices

• US 5,414,618 A
• Filed: 12/21/1993
• Issued: 05/09/1995
• Est. Priority Date: 07/18/1990
• Status: Expired due to Fees

• Current Assignee: Toro Company (Toro)
• Original Assignee: Toro Company (Toro)
• Inventors: Siddiqui, Uzair, Benmergui, Alberto D., Mock, Gerald L.
• Primary Examiner(s): Envall, Jr., Roy N.
• Assistant Examiner(s): BROWN, THOMAS
• Application Number:
  US08/172,518
• Time in Patent Office: 504 Days
• Field of Search: 364/140-147, 364/420, 239/67-70, 239/63, 137/78.2, 137/78.3, 137/624.12, 137/624.11
• US Class Current: 700/16
• CPC Class Codes: A01G 25/16 Control of watering
• CPC Class Codes: G05B 19/0426 Programming the control sequence
• CPC Class Codes: G05B 19/0428 Safety, monitoring G05B19/0423 takes precedence

Abstract

An improved irrigation controller of solid state design utilizes a microcomputer which retains and executes a watering schedule. A plurality of analog data input devices are provided with one input device being assigned to input one value of at least one watering schedule parameter having a number of possible values. Each analog data input device comprises a potentiometer, connected between high and low reference voltages, which has a variable output voltage determined by the setting or position of the input device on the controller housing, with different output voltages representing different values of the parameter. The output voltage is determined by charging a capacitor using a constant current source and by timing how long it takes the capacitor to reach the output voltage. The same capacitor is used for all of the analog data input devices to remove any variability in how different capacitors charge. In addition, the actual instantaneous high and low reference voltages are also read when the output voltage of at least one analog data input device is read.

Claims

1. An improved irrigation controller for individually and automatically controlling water flow to a plurality of individual watering stations in accordance with a programmed watering schedule over a period of days, the controller comprising:

a variable analog data input device for inputting into the schedule at least one selectively changeable value of at least one parameter of the schedule as a function of the position of the analog data input device relative to a housing of the controller, and wherein the analog data input device is accessible to a user for manual manipulation on the housing of the controller and is set by a user by moving the data input device on the controller housing between physically different positions relative to the controller housing with each different position of the data input device relative to the controller housing representing a different value for the parameter, wherein the analog data input device is connected between high and low reference voltages and has an output at which an output voltage may be read with the output voltage lying between the high and low reference voltages and with the output voltage varying as the analog data input device is moved between its different positions on the controller housing; and

means connected to the output of the analog data input device for reading the position of the analog data input device to derive the value of the parameter which has been set by the position of the analog data input device by reading the output voltage appearing at the output of the analog data input device, which comprises;

(a) capacitor means connected to a current source for charging the capacitor means;

(b) logic and control means operatively connected to the capacitor means and to the analog data input device, the logic and control means having means for reading instantaneous values of the high and low reference voltages when reading the output voltage of the analog data input device by charging the capacitor means to the high and low reference voltages and to the output voltage of the analog data input device and by timing the amount of time it takes the capacitor means to charge to the high and low reference voltages and the output voltage of the analog data input device to derive instantaneous maximum, minimum and actual conversion times respectively; and

wherein the

(c) logic and control means further includes means for performing the following functions for deriving a setting for the analog data input device;

(i) for subtracting the maximum from the minimum conversion times to provide a range;

(ii) for dividing the range by a predetermined number of steps to provide a step size; and

(iii) for subtracting the minimum conversion time from the actual conversion time for the analog data input device and dividing the result by the step size to arrive at a setting expressed as a number of steps in the range.

2. An improved irrigation controller as recited in claim 1, wherein the capacitor means includes a single charging capacitor, wherein the capacitor is connected to the high and low reference voltages and the output of the analog data input device by a plurality of separate channels, and further including means for sequencing through the channels to use the same capacitor in deriving the maximum, minimum and actual conversion times.

3. An improved irrigation controller as recited in claim 1, wherein the at least one parameter is a time related parameter expressed in increments from a maximum value to a minimum value expressing at least one of the time of day or an amount of time, and wherein the number of steps is at least equal to the total number of increments between the maximum and minimum value of the at least one parameter.

4. An improved irrigation controller as recited in claim 1, wherein the charging source for the capacitor means is a constant current source.

5. An improved irrigation controller as recited in claim 1, wherein the analog data input means comprises a variable potentiometer.

6. An improved irrigation controller for individually and automatically controlling water flow to a plurality of individual watering stations in accordance with a programmed watering schedule over a period of days, the controller including:

a variable analog data input device for inputting into the schedule at least one selectively changeable value of at least one parameter of the schedule as a function of the position of the analog data input device relative to a housing of the controller, and wherein the analog data input device is accessible to a user for manual manipulation on the housing of the controller and is set by a user by moving the data input device on the controller housing between physically different positions relative to the controller housing with each different position of the data input device relative to the controller housing representing a different value for the parameter, wherein the analog data input device is connected between high and low reference voltages and has an output at which an output voltage may be read with the output voltage lying between the high and low reference voltages and with the output voltage varying as the analog data input device is moved between its different positions on the controller housing; and

means connected to the output of the analog data input device for reading the position of the analog data input device to derive the value of the parameter which has been set by the position of the analog data input device by reading the output voltage appearing at the output of the analog data input device, the reading means further including means for reading instantaneous values of the high and low reference voltages when reading the output voltage of the analog data input device to better calibrate the setting represented by the output voltage of the analog data input device.

7. An improved irrigation controller as recited in claim 6, wherein the analog data input means comprises a variable potentiometer.

8. An improved irrigation controller for individually and automatically controlling water flow to a plurality of individual watering stations in accordance with a programmed watering schedule over a period of days, the controller including

a variable analog data input device for inputting into the schedule at least one selectively changeable value of at least one parameter of the schedule as a function of the position of the analog data input device relative to a housing of the controller, and wherein the analog data input device is accessible to a user for manual manipulation on the housing of the controller and is set by a user by moving the data input device on the controller housing between physically different positions relative to the controller housing with each different position of the data input device relative to the controller housing representing a different value for the parameter, wherein the analog data input device is connected between high and low reference voltages and has an output at which an output voltage may be read with the output voltage lying between the high and low reference voltages and with the output voltage varying as the analog data input device is moved between its different positions on the controller housing;

and

means connected to the output of the analog data input device for reading the position of the analog data input device to derive the value of the parameter which has been set by the position of the analog data input device by reading the output voltage appearing at the output of the analog data input device, which comprises;

a capacitor charged by a constant current source; and

means for timing the amount of time it takes the capacitor to charge to the output voltage of the analog data input device.

9. An improved irrigation controller as recited in claim 8, wherein the analog data input means comprises a variable potentiometer.

10. An improved irrigation controller for individually and automatically controlling water flow to a plurality of individual watering stations in accordance with a programmed watering schedule over a period of days, the controller including:

(a) data input means for allowing the user to input a watering schedule comprising a plurality of values for at least one parameter, wherein the data input means comprises a plurality of discrete analog data input devices which correspond in number to the number of the plurality of values which may be input for the at least one parameter such that a single and different analog data input device inputs a single value for the at least one parameter into the watering schedule, wherein the analog data input devices are accessible to a user for manual manipulation on a housing of the controller and are set by a user by moving each data input device on the controller housing between physically different positions relative to the controller housing with each different position of the data input device relative to the controller housing representing a different value for the at least one chosen parameter; and

wherein each analog data input device is connected between high and low reference voltages and has an output at which an output voltage may be read with the output voltage lying between the high and low reference voltages and with the output voltage thereof varying as each analog data input device is moved between its different positions on the controller housing; and

(b) means connected to the outputs of all the analog data input devices for reading the positions of all the analog data input devices to derive the values of the at least one parameter which has been set by the positions of the analog data input devices by reading the output voltages appearing at the outputs of the analog data input devices, which comprises;

(i) a single capacitor charged by a current source;

(ii) means for timing the amount of time it takes the capacitor to charge to the output voltage of a selected one of the analog data input devices to thereby derive a setting corresponding to the position of the selected one of the analog data input devices; and

(iii) means for sequentially charging the single capacitor and for timing the amount of time it takes the capacitor to charge to the output voltage for each of the analog data input devices such that the same capacitor is used in reading the output voltages of all of the analog data input devices, thereby to enhance the consistency of the settings derived from one analog data input device to the next.