Alignment control system

Claim 2

In self-propelled sprinkler irrigation apparatus of the type comprising, in operative combination, elongated fluid distribution means provided by a plurality of articulately coupled sprinkler sections pivotally movable with respect to one another, said fluid distribution means adapted for rotation about a central point along a circular path; respective drive means associated with each of said sections which, when actuated, propel secTions along said circular path; and alignment control means for maintaining adjacent ones of said sections substantially aligned with respect to one another, during said rotation, along a line corresponding to the radius of said circular path, the improvement wherein said alignment control means comprises: a. first sensor means for detecting the relative pivotal movement of adjacent sections with respect to one another out of said alignment and producing a first electrical signal indicative of said misalignment, said first sensor means comprising pivotal detection means responsive to the said relative pivotal movement and signal generating means for producing said first electrical signal, said signal generating means being operatively responsive to the movement of said pivotal detection means into and out of non-contact communication with said signal generating means; and b. electronic control means for actuating one of said drive means in response to said first electrical signal, thereby to propel its associated section into alignment with said adjacent section.

Claim 3

The improvement as defined by claim 1 wherein said first sensor means is disposed at the intersection of said adjacent sections.

Claim 4

The improvement as defined by claim 1 wherein said signal generating means comprises a photodetector sensor assembly including light sensor means and light source means for directing light at said light sensor, and said pivotal detection means comprises light interrupting means operatively movable into and out of light interrupting relationship with said light source and said light sensor, said operative movement being in response to the pivoting of said adjacent sections into and out of said alignment.

Claim 5

The improvement as defined by claim 3 wherein said operative movement is effective to move said light interrupting means out of said light interrupting relationship with said light source and said light sensor; and means are coupled to said light sensor to produce said first electrical signal when said adjacent sections are out of said alignment.

Claim 6

In self-propelled sprinkler irrigation apparatus of the type comprising, in operative combination, elongated fluid distribution means provided by a plurality of articulately coupled sprinkler sections pivotally movable with respect to one another, said fluid distribution means adapted for rotation about a central point along a circular path; respective drive means associated with each of said sections which, when actuated, propel sections along said circular path; and alignment control means for maintaining adjacent ones of said sections substantially aligned with respect to one another, during said rotation, along a line corresponding to the radius of said circular path, the improvement wherein said alignment control means comprises: a. first sensor means for detecting the relative pivotal movement of adjacent sections with respect to one another out of said alignment and producing a first electrical signal indicative of said misalignment, said first sensor means comprising pivotal detection means responsive to the said relative pivotal movement and signal generating means for producing said first electrical signal, said pivotal detection means being in continuous movable contact with said signal generating means during the said relative pivotal movement of said adjacent sections in either one of the two opposite directions of misalignment, the first electrical signal being produced in response to the movable contact of said pivotal detection means and when said adjacent sections reach a minimum degree of misalignment in either of said two opposite directions; and b. electronic control means for actuating one of said drive means in response to said first electrical signal, thereby to propel its associated section into alignment with said adjacent section.

Claim 7

In self-propelled sprinkler irrigation apparatus of the type comprising, in operative combination, elongated fluid distribution means provided by a plurality of articulately coupled sprinkler sections pivotally movable with respect to one another, said fluid distribution means adapted for rotation about a central point along a circular path; respective drive means associated with each of said sections which, when actuated, propel sections along said circular path; and alignment control means for maintaining adjacent ones of said sections substantially aligned with respect to one another, during said rotation, along a line corresponding to the radius of said circular path, the improvement wherein said alignment control means comprises: a. first sensor means for detecting the relative pivotal movement of adjacent sections with respect to one another out of said alignment and producing a first electrical signal indicative of said misalignment, said first sensor means comprising pivotal detection means responsive to the said relative pivotal movement and signal generating means for producing said first electrical signal, said pivotal detection means being in continuous movable contact with said signal generating means during the said relative pivotal movement of said adjacent sections in either one of the two opposite directions of misalignment, the first electrical signal being produced in response to the movable contact of said pivotal detection means and when said adjacent sections reach a minimum degree of misalignment in either of said two opposite directions; and b. electronic control means for actuating one of said drive means in response to said first electrical signal, thereby to propel its associated section into alignment with said adjacent section.

Claim 8

The improvement as defined by claim 5 wherein said first sensor means is disposed at the intersection of said adjacent sections.

Claim 9

The improvEment as defined by claim 5, wherein said first sensor means is a potentiometer sensor assembly having wiper arm means operatively coupled to one of said adjacent sections to vary the output voltage from said potentiometer in response to the pivotal movement of adjacent sections into and out of said alignment; and means are coupled to said potentiometer to produce said first electrical signal when said adjacent sections reach said minimum degree of misalignment.

Claim 10

In self-propelled sprinkler irrigation apparatus of the type comprising, in operative combination, elongated fluid distribution means provided by a plurality of articulately coupled sprinkler sections pivotally movable with respect to one another, said fluid distribution means adapted for rotation about a central point along a circular path; respective drive means associated with each of said sections which, when actuated, propel sections along said circular path; and alignment control means for maintaining adjacent ones of said sections substantially aligned with respect to one another, during said rotation, along a line corresponding to the radius of said circular path, the improvement wherein said alignment control means comprises: a. first sensor means for detecting the relative pivotal movement of adjacent sections with respect to one another out of said alignment and producing a first electrical signal indicative of said misalignment, b. electronic control means for actuating one of said drive means in response to said first electrical signal, thereby to propel its associated section into alignment with said adjacent section, and c. second sensor means for detecting the rotational direction which said drive means, if actuated, will propel its associated section along said circular path and producing a second electrical signal having states indicative of said rotational direction.

Claim 11

In self-propelled sprinkler irrigation apparatus of the type comprising, in operative combination, elongated fluid distribution means provided by a plurality of articulately coupled sprinkler sections pivotally movable with respect to one another, said fluid distribution means adapted for rotation about a central point along a circular path; respective drive means associated with each of said sections which, when actuated, propel sections along said circular path; and alignment control means for maintaining adjacent ones of said sections substantially aligned with respect to one another, during said rotation, along a line corresponding to the radius of said circular path, the improvement wherein said alignment control means comprises: a. first sensor means for detecting the relative pivotal movement of adjacent sections with respect to one another out of said alignment and producing a first electrical signal indicative of said misalignment, b. electronic control means for actuating one of said drive means in response to said first electrical signal, thereby to propel its associated section into alignment with said adjacent section, and c. second sensor means for detecting the rotational direction which said drive means, if actuated, will propel its associated section along said circular path and producing a second electrical signal having states indicative of said rotational direction.

Claim 12

The improvement as defined by claim 8 wherein said first sensor means comprises a photodetector sensor assembly including light sensor means, light source means for directing light at said light sensor, and light interrupting means operatively movable into and out of light interrupting relationship with said light source and said light sensor, said operative movement being in response to the pivoting of said adjacent sections into and out of said alignment.

Claim 13

The improvement as defined by claim 8 wherein said first sensor means is a potentiometer sensor assembly having wiper arm means operatively coupled to one of said adjacent sections to vary the output voltage from said potentiometer in response to the pivotal movement of adjacent sections into and out of said alignment; and means are coupled to said potentiometer to produce said first electrical signal when said adjacent sections reach said minimum degree of misalignment.

Claim 14

The improvement as defined by claim 8 wherein said drive means are reversible alternating current motors and said second sensor means detects said relative rotational direction by sensing the phase relationship of supply voltages to said motors.

Claim 15

The improvement as defined by claim 8 wherein the first electrical signal from said first sensor means has states indicative of which of two angular directions the said adjacent sections are in pivotal misalignment, and said electronic control means further includes comparator means coupled to said first and second sensor means for comparing the respective states of said first and second electrical signals to actuate said drive means only when the so-compared electrical signals indicate that the actuation of said drive means will propel its associated section into alignment with the adjacent section.

Claim 16

The improvement as defined by claim 12 further including means coupled to said first sensor means for interrupting power to all of said drive means when said adjacent sections are in excessive pivotal misalignment.

Claim 17

The improvement as defined by claim 12 wherein said first sensor means comprises a photodetector sensor assemblY including light source means, light sensor means, and light interrupting means operatively movable between a first position to allow light from said light source means to impinge upon said light sensor means and a second position for preventing the light from reaching said sensor means, said operative movement being in response to the pivoting of said adjacent sections into and out of said alignment.

Claim 18

The improvement as defined by claim 14 wherein said photodetector sensor assembly comprises two light sensors, two light sources respectively operatively paired with and focused at said two light sensors, and said light interrupting means is operatively movable out of light interrupting relationship with one of the paired sets of light sensors and light sources when said adjacent sections are pivoted in one of said angular directions and out of light interrupting relationship with the other paired set of light sensors and light sources when said adjacent sections are pivoted in the other angular direction.

Claim 19

The improvement as defined by claim 12 wherein said first sensor means is a potentiometer sensor assembly having wiper arm means operatively coupled to one of said adjacent sections to vary the output voltage from said potentiometer in response to the pivotal movement of adjacent sections into and out of said alignment, and means are coupled to said potentiometer to produce said first electrical signal when said adjacent sections reach a minimum degree of misalignment.

Claim 20

The improvement as defined by claim 16 wherein said wiper is movable in one direction when said adjacent sections are pivoted into misalignment in one of said angular directions and movable in an opposite direction when said adjacent sections are pivoted in the other angular direction, thereby to produce said first electrical signal having one or the other of the two states.

Claim 21

The improvement as defined by claim 15 further including means coupled to said photodetector sensor assembly for interrupting power to all of said drive means when said light interrupting means is operatively moved out of light interrupting relationship with both of said paired sets.

Claim 22

The improvement as defined by claim 17 further including means coupled to said potentiometer sensor assembly for interrupting power to all of said drive means when said wiper arm is moved in either direction beyond a predetermined range.

Claim 23

An electronic control system for maintaining substantially linear alignment of adjacent interconnected fluid conduit sections relatively pivotable with respect to one another in a generally horizontal drive plane, each of said adjacent sections having respective drive means coupled thereto, when energized, for propelling its coupled section in either one or the other of opposite directions in said drive plane, comprising: a. first pivotal means operatively coupled to one of said adjacent sections for producing a first electrical signal having states indicative of the occurrence and angular direction of the relative pivotal movement of said adjacent sections out of said linear alignment, b. second directional detector means for producing a second electrical signal having states indicative of which of the said opposite directions a particular drive means will propel, if energized, its coupled section, and c. third means coupled to said first and second means for comparing the states of said first and second electrical signals and energizing said particular drive means when the so compared states indicate the energizing will bring said adjacent sections into alignment.

Claim 24

An electronic control system for maintaining substantially linear alignment of adjacent interconnected fluid conduit sections relatively pivotable with respect to one another in a generally horizontal drive plane, each of said adjacent sections having respective drive means coupled thereto, when energized, for propelling its coupled section in either one or the other of opposite directions in said drive plane, comprising: a. first pivotal means operatively coupled to one of said adjacent sections for producing a first electrical signal having states indicative of the occurrence and angular direction of the relative pivotal movement of said adjacent sections out of said linear alignment, b. second directional detector means for producing a second electrical signal having states indicative of which of the said opposite directions a particular drive means will propel, if energized, its coupled section, and c. third means coupled to said first and second means for comparing the states of said first and second electrical signals and energizing said particular drive means when the so compared states indicate the energizing will bring said adjacent sections into alignment.

Claim 25

The control system as defined by claim 20 wherein said first pivotal detector means comprises pulse generating means having an input terminal and an output terminal, a pulse produced at said output terminal having one digital state when a voltage at the input terminal is of one magnitude and having a different digital state when the voltage at said input terminal is of a lesser magnitude, and means couPled to the said input terminal of said pulse generator for producing said voltages of said one or lesser magnitude in response to the pivoting of adjacent sections out of said linear alignment in one angular direction or in an opposite angular direction.

Claim 26

The system as defined by claim 21 wherein said voltage producing means coupled to the input of said pulse generating means is a pair of phototransistors respectively conducting during said one and said opposite angular pivotal direction.

Claim 27

The control system as defined by claim 22 wherein said pulse generator is an operational amplifier.

Claim 28

The control system as defined by claim 21 wherein said voltage producing means coupled to the input of said pulse generating means comprises variable resistance means, and a wiper movable along said variable resistance means for increasing or decreasing the resistance thereof in response to the pivoting of said adjacent sections out of said linear alignment in one or the opposite angular direction.

Claim 29

The control system as defined by claim 24 wherein said pulse generator is an operational amplifier.

Claim 30

The apparatus as defined by claim 21 wherein said second directional detector is a phase detection network for determining the relative phase relationship of supply voltages for said drive means.

Claim 31

The control system as defined by claim 26 wherein said phase detection network comprises a pulse generator having an input terminal and an output terminal, means coupled to said input terminal for producing said second electrical signal having one digital state when the phase relationship of the said supply voltages indicate that said drive means will be propelled in one of said opposite directions and a different digital state when said phase relationship indicates that said drive means will be propelled in the other opposite direction, said means comprising a pulse width modulated flip-flop having trigger pulses derived from said supply voltages.

Claim 32

The control system as defined by claim 22 wherein said phototransistors are coupled in series, and means are coupled to the output of one of said phototransistors for interrupting power to all of said drive means in response to the conduction of both phototransistors, the conduction of both phototransistors occurring as a consequence of excessive linear misalignment between adjacent sections.

Claim 33

The control system as defined by claim 24 wherein means are coupled to said variable resistance means for interrupting power to all of said drive means when said wiper is moved in either direction beyond a predetermined range representing excessive linear misalignment between adjacent sections.

Claim 34

The control system as defined by claim 20 wherein said third means comprises triggering means coupled to the output of a logic comparator effecting said comparing for selectively coupling supply voltages to said drive means.

Claim 35

The control system as defined by claim 30 wherein said selective coupling is by way of solid-state triacs selectively and simultaneously gated into conduction by said triggering means.

Claim 36

Alignment control system for a pivotal irrigation apparatus of the type comprising elongated fluid distribution means provided by a string of sprinkler sections in end-to-end relationship relatively pivotable with respect to one another in a generally horizontal drive plane, said fluid distribution means adapted for rotation about a central point along a circular path, reversible alternating current motors for respectively propelling each of said sections simultaneously in the clockwise or counterclockwise direction on said drive plane along said circular path, one of said motors being actuated for continuously propelling an outer section along said path, a multiphase voltage supply for said motors, said alignment control system selectively and intermittently actuating motors associated with intermediate sections to maintain substantially linear alignment of adjacent sections in said horizontal drive plane aNd comprising: a. a pivotal detector comprising a photodetector sensor assembly including photodetector means coupled to one of said sprinkler sections, said photodetector means including a pair of spaced light emitting diodes, a pair of phototransistors so spaced to respectively receive light from said light emitting diodes; light interrupting vane means connected to the adjacent section to said one section, said vane means extending over the intersection of said adjacent sections and so disposed with respect to said photodetector means to interrupt the light from reaching either phototransistors when said adjacent sections are linearly aligned, to allow light to reach one of the phototransistors to cause said one phototransistor to conduct when the adjacent sections are pivoted out of said alignment in one angular direction, and to reach the other phototransistor and to cause said other phototransistor to conduct when the adjacent sections are pivoted out of said alignment in the other angular direction, b. first operational amplifier means coupled to said pivotal detector for producing a first electrical signal having first and second digital states respectively indicative of in which of said angular directions the adjacent sections are pivoted, c. a directional detector means for determining whether said sections are being propelled in the said clockwise or counterclockwise directions, said directional detector comprising a phase detection network for determining the phase relationships of said multiphase voltage supply, comprising second operational amplifier means having an input terminal and an output terminal, pulse width modulated flip-flop means having trigger pulses derived from said multiphase voltage supply lines coupled to said input terminal for producing a second electrical signal at said output terminal having first and second digital states respectively indicative of said clockwise and counterclockwise directions, d. logic comparator means having inputs thereto respectively coupled to said first and second operational amplifiers for comparing the states of said first and second electrical signals and generating a trigger signal when the so-compared states indicate that the actuation of the said motor will bring said adjacent sections into said linear alignment, and e. triggering means responsive to said trigger signal for actuating switching means selectively coupling, when actuated, said voltage supply to said motors.

Claim 37

Alignment control system for a pivotal irrigation apparatus of the type comprising elongated fluid distribution means provided by a string of sprinkler sections in end-to-end relationship relatively pivotable with respect to one another in a generally horizontal drive plane, said fluid distribution means adapted for rotation about a central point along a circular path, reversible alternating current motors for respectively propelling each of said sections simultaneously in the clockwise or counterclockwise direction on said drive plane along said circular path, one of said motors being actuated for continuously propelling an outer section along said path, a multiphase voltage supply for said motors, said alignment control system selectively and intermittently actuating motors associated with intermediate sections to maintain substantially linear alignment of adjacent sections in said horizontal drive plane aNd comprising: a. a pivotal detector comprising a photodetector sensor assembly including photodetector means coupled to one of said sprinkler sections, said photodetector means including a pair of spaced light emitting diodes, a pair of phototransistors so spaced to respectively receive light from said light emitting diodes; light interrupting vane means connected to the adjacent section to said one section, said vane means extending over the intersection of said adjacent sections and so disposed with respect to said photodetector means to interrupt the light from reaching either phototransistors when said adjacent sections are linearly aligned, to allow light to reach one of the phototransistors to cause said one phototransistor to conduct when the adjacent sections are pivoted out of said alignment in one angular direction, and to reach the other phototransistor and to cause said other phototransistor to conduct when the adjacent sections are pivoted out of said alignment in the other angular direction, b. first operational amplifier means coupled to said pivotal detector for producing a first electrical signal having first and second digital states respectively indicative of in which of said angular directions the adjacent sections are pivoted, c. a directional detector means for determining whether said sections are being propelled in the said clockwise or counterclockwise directions, said directional detector comprising a phase detection network for determining the phase relationships of said multiphase voltage supply, comprising second operational amplifier means having an input terminal and an output terminal, pulse width modulated flip-flop means having trigger pulses derived from said multiphase voltage supply lines coupled to said input terminal for producing a second electrical signal at said output terminal having first and second digital states respectively indicative of said clockwise and counterclockwise directions, d. logic comparator means having inputs thereto respectively coupled to said first and second operational amplifiers for comparing the states of said first and second electrical signals and generating a trigger signal when the so-compared states indicate that the actuation of the said motor will bring said adjacent sections into said linear alignment, and e. triggering means responsive to said trigger signal for actuating switching means selectively coupling, when actuated, said voltage supply to said motors.

Claim 38

The control system as defined by claim 32 further including means coupled to said pivotal detector for interrupting said voltage supply to all of said motors when any of said adjacent sections are pivoted into excessive misalignment.

Claim 39

The control system as defined by claim 32 wherein said switching means are a pair of solid-state triacs disposed between said voltage supply and said motors.

Claim 40

The control system as defined by claim 34 wherein said triggering means comprises a free-running magnetic multivibrator having outputs therefrom coupled to said triacs.

Claim 41

Alignment control system for a pivotal irrigation apparatus of the type comprising elongated fluid distribution means provided by a string of sprinkler sections in end-to-end relationship relatively pivotable with respect to one another in a generally horizontal drive plane, said fluid distribution means adapted for rotation about a central point along a circular path, reversible alternating current motors for respectively propelling each of said sections simultaneously in the clockwise or counterclockwise direction on said drive plane along said circular path, one of said motors being actuated for continuously propelling an outer section along said path, a multiphase voltage supply for said motors, said alignment control system selectively and intermittently actuating motors associated with intermediate sections to maintain substantially linear alignment of adjacent sections in said horizontal drive plane and comprising: a. a pivotal detectoR comprising a potentiometer sensor assembly having wiper arm means rotatably coupled to one of said sprinkler sections to vary the output voltage from said potentiometer to one value when an adjacent section is in pivotal relationship thereto in one angular direction and to another value when said adjacent section is in pivotal relationship thereto in the other angular direction, b. first operational amplifier means coupled to said pivotal detector for producing a first electrical signal having first and second digital states respectively indicative of which of said angular directions the adjacent sections are pivoted, c. a directional detector means for determining whether said sections are being propelled in the said clockwise or counterclockwise directions, said directional detector comprising a phase detection network for determining the phase relationships of said multiphase voltage supply, comprising section operational amplifier means having an input terminal and an output terminal, pulse width modulated flip-flop means having trigger pulses derived from said multiphase voltage supply lines coupled to said input terminal for producing a second electrical signal at said output terminal having first and second digital states respectively indicative of said clockwise and counterclockwise directions, d. logic comparator means having inputs thereto respectively coupled to said first and second operational amplifiers for comparing the states of said first and second electrical signals and generating a trigger signal when the so-compared states indicate that the actuation of the said motor will bring said adjacent sections into said linear alignment, and e. triggering means responsive to said trigger signal for actuating switching means selectively coupling, when actuated, said voltage supply to said motors.

Claim 42

Alignment control system for a pivotal irrigation apparatus of the type comprising elongated fluid distribution means provided by a string of sprinkler sections in end-to-end relationship relatively pivotable with respect to one another in a generally horizontal drive plane, said fluid distribution means adapted for rotation about a central point along a circular path, reversible alternating current motors for respectively propelling each of said sections simultaneously in the clockwise or counterclockwise direction on said drive plane along said circular path, one of said motors being actuated for continuously propelling an outer section along said path, a multiphase voltage supply for said motors, said alignment control system selectively and intermittently actuating motors associated with intermediate sections to maintain substantially linear alignment of adjacent sections in said horizontal drive plane and comprising: a. a pivotal detectoR comprising a potentiometer sensor assembly having wiper arm means rotatably coupled to one of said sprinkler sections to vary the output voltage from said potentiometer to one value when an adjacent section is in pivotal relationship thereto in one angular direction and to another value when said adjacent section is in pivotal relationship thereto in the other angular direction, b. first operational amplifier means coupled to said pivotal detector for producing a first electrical signal having first and second digital states respectively indicative of which of said angular directions the adjacent sections are pivoted, c. a directional detector means for determining whether said sections are being propelled in the said clockwise or counterclockwise directions, said directional detector comprising a phase detection network for determining the phase relationships of said multiphase voltage supply, comprising section operational amplifier means having an input terminal and an output terminal, pulse width modulated flip-flop means having trigger pulses derived from said multiphase voltage supply lines coupled to said input terminal for producing a second electrical signal at said output terminal having first and second digital states respectively indicative of said clockwise and counterclockwise directions, d. logic comparator means having inputs thereto respectively coupled to said first and second operational amplifiers for comparing the states of said first and second electrical signals and generating a trigger signal when the so-compared states indicate that the actuation of the said motor will bring said adjacent sections into said linear alignment, and e. triggering means responsive to said trigger signal for actuating switching means selectively coupling, when actuated, said voltage supply to said motors.

Claim 43

The control system as defined by claim 36 further including means coupled to said pivotal detector for interrupting said voltage supply to all of said motors when any of said adjcent sections are pivoted into excessive misalignment.

Claim 44

The control system as defined by claim 36 wherein said switching means are a pair of solid-state triacs disposed between said voltage supply and said motors.

Claim 45

The control system as defined by claim 38 wherein said triggering means comprises a free-running magnetic multivibrator having outputs therefrom coupled to said triacs.

Claim 46

Phase detection network means for determining the relative phase relationship between two time-varying voltages, said network comprising a pulse width modulated flip-flop, means respectively coupling said time-varying voltages to a pair of inputs to said flip-flop for supplying trigger input pulses thereto, an operational amplifier having inverting and non-inverting terminals and an output terminal, capacitor means having one end coupled to the output of said flip-flop and said inverting input terminal, said capacitor means in combination with said flip-flop being effective to produce a voltage pulse at the said output terminal having one digital state when said two voltages are defined by one phase relationship and having a different digital state when said two voltages are defined by a different phase relationship.

Claim 47

Phase detection network means for determining the relative phase relationship between two time-varying voltages, said network comprising a pulse width modulated flip-flop, means respectively coupling said time-varying voltages to a pair of inputs to said flip-flop for supplying trigger input pulses thereto, an operational amplifier having inverting and non-inverting terminals and an output terminal, capacitor means having one end coupled to the output of said flip-flop and said inverting input terminal, said capacitor means in combination with said flip-flop being effective to produce a voltage pulse at the said output terminal having one digital state when said two voltages are defined by one phase relationship and having a different digital state when said two voltages are defined by a different phase relationship.