Irrigation apparatus

Claim 2

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus for controlling the linear alignment of said irrigation apparatus by causing sections of said irrigation apparatus to move or not move in a predetermined, automatic manner, comprising a misalignment sensor mechanically connected to said irrigation apparatus for sensing possible linear misalignments of said irrigation apparatus, correctable by said alignment control system, and for causing electrical circuits to be established or disestablished in response to the presence or absence of said possible misalignments, said misalignment sensor comprising: permanent magnet means connected to a section of said irrigation apparatus for generating a field of magnetic flux, magnetic switch means, operable by said field of magnetic flux and also connected to said section of said irrigation apparatus and electrically connected to said electrical circuits, and magnetic shielding means connected to another and adjacent section of said irrigation apparatus in such position as to magnetically shield or not shield said magnetic switch means from said field of magnetic flux in a predetermined fashion thereby causing said magnetic switch means to establish or disestablish said electrical circuits in accordance with said presence or absence of misalignment of said irrigation apparatus.

Claim 3

The apparatus according to claim 1 wherein circuitry operated by said switching means includes a delay circuit responsive to an indication of misalignment for causing movement of the misaligned section of the irrigation apparatus after said misalignment has been detected for a predetermined time.

Claim 4

The apparatus according to claim 2 wherein said delay circuit is sensitive to realignment of the irrigation apparatus for bringing about immediate discontinuance of movement of the misaligned section when realignment has taken place.

Claim 5

The apparatus according to claim 3 wherein said delay circuit comprises an integrating circuit including a resistor and capacitor, said resistor being shunted by a circuit including a unidirectional conducting device which is operative to reduce the time constant of said circuit for the polarity of input when realignment has taken place.

Claim 6

The apparatus according to claim 1 further including a power phase rotation detection circuit, and logic means responsive to phase rotation and to operation of said magnetic switch means to bring about correct realignment dependent upon the direction of rotation of the irrigation apparatus.

Claim 7

The apparatus according to claim 1 wherein said magnetic shielding means comprises a plate of magnetic material and an aperture, the edge of which is normally aligned between said permanent magnet means and said magnetic switch means.

Claim 8

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus for causing sections of said irrigation apparatus to move or not to move in a predetermined, automatic manner, comprising an overtravel sensor, mechanically connected to said irrigation apparatus, for sensing possible linear misalignments of said irrigation apparatus uncorrectable by said alignment control system, and for causing electrical circuits to be established or disestablished in response to the presence or absence of said misalignments, said circuits causing said alignment control system to become de-energized and inoperative in response to the presence of said misalignments, said overtravel sensor comprising: permanent magnet means connected to a section of said irrigation apparatus for generating a field of magnetic flux, magnetic switch means, operable by said field of magnetic flux, also connected to said section of said irrigation apparatus and electrically connected to said electrical circuits, and magnetic shielding means connected to another and adjacent section of said irrigation apparatus in such position as to shield or not shield said magnetic switch means from said field of magnetic flux in a predetermined fashion thereby causing said magnetic switch means to establish or disestablish said electrical circuits in accordance with said presence or absence of misalignment of said irrigation apparatus.

Claim 9

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus for causing sections of said irrigation apparatus to move or not to move in a predetermined, automatic manner, comprising an overtravel sensor, mechanically connected to said irrigation apparatus, for sensing possible linear misalignments of said irrigation apparatus uncorrectable by said alignment control system, and for causing electrical circuits to be established or disestablished in response to the presence or absence of said misalignments, said circuits causing said alignment control system to become de-energized and inoperative in response to the presence of said misalignments, said overtravel sensor comprising: permanent magnet means connected to a section of said irrigation apparatus for generating a field of magnetic flux, magnetic switch means, operable by said field of magnetic flux, also connected to said section of said irrigation apparatus and electrically connected to said electrical circuits, and magnetic shielding means connected to another and adjacent section of said irrigation apparatus in such position as to shield or not shield said magnetic switch means from said field of magnetic flux in a predetermined fashion thereby causing said magnetic switch means to establish or disestablish said electrical circuits in accordance with said presence or absence of misalignment of said irrigation apparatus.

Claim 10

The apparatus according to claim 7 wherein said magnetic shielding means includes an aperture disposed between said permanent magnet means and said magnetic switch means, said magnetic shielding means being movable with said adjacent section or irrigation apparatus by an amount equalling at least the width of said aperture, the width of said aperture defining a range of alignment condition beyond which shielding of said switch means takes place to define gross misalignment in response to which said alignment control system is de-energized.

Claim 11

The apparatus according to claim 7 including a plurality of said control systems wherein said magnetic switch means are connected in series and including circuitry for detecting the opening of one of said magnetic switch means to de-energize said system.

Claim 12

The apparatus according to claim 9 including a resistor in series with said magnetic switch means, and including circuitry for applying a voltage to the series connection of said resistor and magnetic switch means and for detecting a voltage level over such series connection indicating closure of said magnetic switch means and for indicating either opening or shorting of said magnetic switch means for de-energizing said control system.

Claim 13

The apparatus according to claim 9 further including capacitive means between each said magnetic switch means and circuit common, a monostable oscillator having said magnetic switch means and capacitive means in the timing circuit thereof, and means to count the period of said oscillator for determining which of the magnetic switch means has opened whereby to identify the irrigation apparatus associated with the open magnetic switch means.

Claim 14

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus for controlling the linear alignment of said irrigation apparatus by causing sections of said irrigation apparatus to move or not move in a predetermined, automatic manner, comprising an electrical delay circuit for causing the initiation of said movement to be delayed in time by an operably adjustable amount, and for causing the termination of said movement to be substantially undelayed in time.

Claim 15

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus for controlling the linear alignment of said irrigation apparatus by causing sections of said irrigation apparatus to move or not move in a predetermined, automatic manner, comprising an electrical delay circuit for causing the initiation of said movement to be delayed in time by an operably adjustable amount, and for causing the termination of said movement to be substantially undelayed in time.

Claim 16

The apparatus according to claim 12 wherein said delay circuit includes an integrating circuit comprising a resistor and capacitor, and unidirectional connection means coupled across said resistor for changing the time constant of said integrating circuit for a given polarity of input applied thereto.

Claim 17

In self-propelled sprinkler irrigation apparatus, an alignment control system, connected to said irrigation apparatus for controlling the linear alignment of said irrigation apparatus, comprising: a plurality of sensors, mechanically connected to said irrigation apparatus for sensing linear misalignments of said irrigation apparatus, correctable by said alignment control system, and for sensing other and gross linear misalignments of said irrigation apparatus, uncorrectable by said alignment control system, and for causing electrical circuits to be established or disestablished in response to said misalignments, each said sensor comprising: an apertured metal sheet connected to a section of said irrigation apparatus, a slotted housing unit fixedly connected to another and adjacent section of said irrigation apparatus and allowing said metal sheet to be disposed in said slot, permanent magnet means fixedly connected to one face of said slotted housing unit for establishment of magnetic flux,

Claim 18

In self-propelled sprinkler irrigation apparatus, an alignment control system, connected to said irrigation apparatus for controlling the linear alignment of said irrigation apparatus, comprising: a plurality of sensors, mechanically connected to said irrigation apparatus for sensing linear misalignments of said irrigation apparatus, correctable by said alignment control system, and for sensing other and gross linear misalignments of said irrigation apparatus, uncorrectable by said alignment control system, and for causing electrical circuits to be established or disestablished in response to said misalignments, each said sensor comprising: an apertured metal sheet connected to a section of said irrigation apparatus, a slotted housing unit fixedly connected to another and adjacent section of said irrigation apparatus and allowing said metal sheet to be disposed in said slot, permanent magnet means fixedly connected to one face of said slotted housing unit for establishment of magnetic flux,

Claim 19

and reed switch means fixedly connected to the opposite face of said slotted housing unit for causing electrical circuits to be established or disestablished according to whether or not said metal sheet is aligned within said slotted housing unit so as to magnetically shield said reed switches from said magnetic flux established by said permanent magnets, or not so to shield when apertures in said sheet are aligned with magnet means and reed switch means, said alignment corresponding to said irrigation apparatus being in linear alignment and misalignment corresponding to said irrigation apparatus being in linear misalignment, a plurality of sensors being mechanically connected to adjacent sections of said irrigation apparatus and electrically connected to one another in such manner as to cause the de-energization of said alignment control system if said irrigation apparatus is in gross linear misalignment.

Claim 20

and reed switch means fixedly connected to the opposite face of said slotted housing unit for causing electrical circuits to be established or disestablished according to whether or not said metal sheet is aligned within said slotted housing unit so as to magnetically shield said reed switches from said magnetic flux established by said permanent magnets, or not so to shield when apertures in said sheet are aligned with magnet means and reed switch means, said alignment corresponding to said irrigation apparatus being in linear alignment and misalignment corresponding to said irrigation apparatus being in linear misalignment, a plurality of sensors being mechanically connected to adjacent sections of said irrigation apparatus and electrically connected to one another in such manner as to cause the de-energization of said alignment control system if said irrigation apparatus is in gross linear misalignment.

Claim 21

The apparatus according to claim 14 further including a plurality of sensors mechanically connected to adjacent sections of said irrigation apparatus, each being responsive to misalignment for energizing movement of a section of irrigation apparatus to establish realignment.

Claim 22

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus comprising: drive means for moving said irrigation apparatus, actuator means electrically connected to said drive means for energizing said drive means, control means electrically connected to said actuator means for controlling said actuator means, and sensors, electrically connected to said control means for sensing the alignment of said irrigation apparatus, each of said sensors comprising a magnet and magnetic switch means coupled to a first section of said irrigation apparatus and an apertured shield coupled to an adjacent section of said irrigation apparatus wherein an edge of the aperture in the shield is normally aligned between the magnet and the switch means, said control means being responsive to actuation and deactuation of said switch means causing said actuating means to energize a said drive means when a sensor indicates misalignment.

Claim 23

In self-propelled sprinkler irrigation apparatus, an alignment control system connected to said irrigation apparatus comprising: drive means for moving said irrigation apparatus, actuator means electrically connected to said drive means for energizing said drive means, control means electrically connected to said actuator means for controlling said actuator means, and sensors, electrically connected to said control means for sensing the alignment of said irrigation apparatus, each of said sensors comprising a magnet and magnetic switch means coupled to a first section of said irrigation apparatus and an apertured shield coupled to an adjacent section of said irrigation apparatus wherein an edge of the aperture in the shield is normally aligned between the magnet and the switch means, said control means being responsive to actuation and deactuation of said switch means causing said actuating means to energize a said drive means when a sensor indicates misalignment.

Claim 24

The combination of claim 16 wherein each said control means comprises: a phase reversal detector for detecting the direction of movement of said irrigation apparatus by reversal of phase of electrical power applied thereto and for generating either of two different electrical signals in response to such detection, a logic circuit electrically connected to said phase reversal detector and an associated said sensor for generating or not generating an electrical signal in response to which of said electrical signals is received from said phase reversal detector and said switch means, and a delay circuit electrically connected to said logic circuit and electrically causing a delay in time of the commencement of movement of said irrigation apparatus to reestablish alignment.