Vehicular material spreader control apparatus

Claim 2

Apparatus for controlling the operation of a vehicular material spreader having means for dispensing material from a reservoir at a controllable rate and means for spreading the dispensed material over a controllable area, said apparatus comprising in combination: first control means for regulating the operation of the dispensing means for causing material to be dispensed at a rate which varies as a function of the ground speed of the vehicular spreader, adjustable second control means for regulating the operation of the spreading means to determine the area covered thereby, and means for automatically changing said dispensing rate when the adjustment of said second control means is altered to maintain constant the density of material spread per unit area independent of change in the area covered, said first control means comprising a control channel having an output for supplying a control signal to the dispensing means to determine the rate of operation thereof, feedback means for supply to a first input to said control channel a feedback signal indicative of the rate of operation of said dispensing means, and means for supplying to a second input to said control channel a reference signal proportional to the ground speed of the vehicular spreader, said control channel being arranged to provide said control signal as a function of the difference between said reference signal and said feedback signal; said second control means including adjustable means for altering the adjustment thereof; and said means for automatically changing the dispensing rate comprising means interrelating said adjustable means with said means for supplying a reference signal to vary the proportional relationship between said reference signal and said ground speed in a direction to maintain said constant spreading density.

Claim 3

Apparatus according to claim 1, wherein said control channel is responsive to electrical input signals; said feedback means including means for providing an electrical feedback signal whose voltage is proportional to the rate of feed of said dispensing means; said means for supplying a reference signal including an adjustable voltage divider having an output and an input, said output being coupled to said second input to the control channel for providing said reference signal thereto, and means for supplying a voltage to said input of the voltage divider which is proportional to said ground speed; and said interrelating means including means for Adjusting said voltage divider to change the relationship between the voltage at its input and the reference signal at its output.

Claim 4

Apparatus according to claim 2, wherein said second control means is responsive to an electrical signal, and said adjustable means therefor includes a second adjustable voltage divider for adjusting a voltage signal applied to said second control means, and said means for adjusting said first voltage divider is coupled for conjoint operation to means for adjusting said second voltage divider.

Claim 5

Apparatus according to claim 3, wherein said second voltage divider has a non-linear characteristic for compensating for non-linearity in the operation of the spreading means.

Claim 6

Apparatus according to claim 1, wherein said first control means comprises a control channel responsive to electrical input signals and having an output for supplying a control signal to the dispensing means to determine the rate of operation thereof, and means for providing said electrical input signals in proportion to the ground speed of the vehicular spreader; and wherein said second control means includes adjustable means for altering the adjustment thereof; and wherein said means for automatically changing the dispensing rate comprises means interrelating said adjustable means with said means for providing said electrical input signals to vary the proportional relationship between said input signals and said ground speed in a direction to maintain said constant spreading density.

Claim 7

Apparatus according to claim 1, wherein means are coupled to said first control means for inhibiting operation of the dispensing means until the ground speed of said vehicular spreader exceeds a predetermined minimum value.

Claim 8

Apparatus according to claim 1, wherein first means are coupled to said first control means for supplying a regulating signal thereto, said first means being selectably adjustable to select a desired application density, and second means are coupled to said first control means selectably actuable for altering said application density without changing the adjustment of said first means.

Claim 9

Apparatus according to claim 1, wherein a signal device is provided, and means interconnect said signal device with said first control means for providing an indication when the ground speed of said spreader exceeds the dispensing capability of said dispensing means.

Claim 10

Apparatus for controlling the operation of a vehicular material spreader having a driven material feeder and an adjustable gate for dispensing material from a reservoir at a controllable rate, and a motor driven spinner for spreading the dispensed material over a controllable area, said apparatus comprising in combination: first control means including an actuator means for regulating the position of the gate to maintain an opening from the reservoir which is controlled thereby in a desired functional relation relative to the ground speed of the vehicular spreader, second control means for controlling the operating speed of the spinner motor to spread the dispensed material over a desired area, means for adjusting said second control means to select the areas covered by the spinner, means for automatically changing the rate at which material is dispensed concomitantly with adjustment of said control means to alter said rate in a direction and magnitude to maintain constant the density of material spread per unit area independent of change in the area covered by the spinner, said means for automatically changing the rate at which material is dispensed comprising a drive train for the feeder which is powered by the spinner motor whereby change in speed of the spinner motor simultaneously alters the speed of both the spinner and the feeder, the said spinner motor being an auxiliary internal combustion engine, and means for automatically preventing operation of the feeder until the vehicular spreader exceeds a predetermined minimum ground speed.

Claim 11

Apparatus for controlling the operation of a vehicular material spreader having a driven material feeder and an adjustable gate for dispensing material from a reservoir at a controllable rate, and a motor driven spinner for spreading the dispensed material over a controllable area, said apparatus comprising in combination: first control means including an actuator means for regulating the position of the gate to maintain an opening from the reservoir which is controlled thereby in a desired functional relation relative to the ground speed of the vehicular spreader, second control means for controlling the operating speed of the spinner motor to spread the dispensed material over a desired area, means for adjusting said second control means to select the areas covered by the spinner, means for automatically changing the rate at which material is dispensed concomitantly with adjustment of said control means to alter said rate in a direction and magnitude to maintain constant the density of material spread per unit area independent of change in the area covered by the spinner, said means for automatically changing the rate at which material is dispensed comprising a drive train for the feeder which is powered by the spinner motor whereby change in speed of the spinner motor simultaneously alters the speed of both the spinner and the feeder, the said spinner motor being an auxiliary internal combustion engine, and means for automatically preventing operation of the feeder until the vehicular spreader exceeds a predetermined minimum ground speed.

Claim 12

Apparatus according to claim 9, wherein said additional meAns comprises a clutch mechanism between said spinner motor and said feeder, said clutch mechanism being normally disengaged, and means coupled to said clutch mechanism and responsive to the ground speed of said vehicular spreader for automatically engaging said clutch mechanism when said minimum ground speed is exceeded.

Claim 13

Apparatus according to claim 9, wherein said means for automatically changing the rate at which material is dispensed includes means for compensating for non-linearity in the operation of the spinner.

Claim 14

Apparatus according to claim 11, wherein said means for compensating for non-linearity comprises means interconnecting said first control means with said means for adjusting said second control means for additionally regulating the position of said gate as a function of selected spinner speed in a direction and magnitude related to said non-linearity to compensate therefor.

Claim 15

Apparatus for controlling the operation of a vehicular material spreader having means for feeding material from a reservoir at a controllable rate, said apparatus comprising in combination: a hydraulic motor for driving said feeding means, a flow control valve for controlling the flow of hydraulic fluid to said motor, an electrically operable position actuator for adjusting said valve, a control circuit for supplying operating current to said position actuator, a limit switch connected in series with an input of said actuator across an output of said control circuit, said switch being coupled mechanically to said actuator for opening the circuit thereto when said actuator reaches a predetermined limiting position, a signal lamp, means coupling said signal lamp to said output of the control circuit, and means for supplying signals to an input of said control circuit proportional to the error between the actual operating speed of said motor and a speed bearing a given functional relationship to the ground speed of the vehicular spreader, said signals being of a character tending to cause adjustment of said valve in a direction tending to reduce said error to zero, said means coupling said signal lamp to said output being responsive to opening of said limit switch only when said error is calling for an adjustment beyond the limiting position for changing the operating condition of said lamp.

Claim 16

Apparatus for controlling the operation of a vehicular material spreader having means for feeding material from a reservoir at a controllable rate, said apparatus comprising in combination: a hydraulic motor for driving said feeding means, a flow control valve for controlling the flow of hydraulic fluid to said motor, an electrically operable position actuator for adjusting said valve, a control circuit for supplying operating current to said position actuator, a limit switch connected in series with an input of said actuator across an output of said control circuit, said switch being coupled mechanically to said actuator for opening the circuit thereto when said actuator reaches a predetermined limiting position, a signal lamp, means coupling said signal lamp to said output of the control circuit, and means for supplying signals to an input of said control circuit proportional to the error between the actual operating speed of said motor and a speed bearing a given functional relationship to the ground speed of the vehicular spreader, said signals being of a character tending to cause adjustment of said valve in a direction tending to reduce said error to zero, said means coupling said signal lamp to said output being responsive to opening of said limit switch only when said error is calling for an adjustment beyond the limiting position for changing the operating condition of said lamp.

Claim 17

Apparatus according to claim 13, wherein said control circuit has two output terminals and means for connecting both of said terminals to ground potential when no error signal is applied to the input of said control circuit, and alternatively connecting one output terminal or the other to a source of electrical energy of given polarity while the other terminal remains grounded when an error signal is present depending upon the direction of the error; and wherein said means coupling said signal lamp is connected to one of said output terminals for energizing said lamp so long as said one output terminal is connected to ground either directly within said control circuit or through a closed circuit including said position actuator.

Claim 18

Apparatus for controlling the operation of a vehicular material spreader having means for feeding material from a reservoir at a controllable rate and spinner means for spreading the material supplied by the feeding means over a controllable area, said apparatus comprising in combination: first and second rotary hydraulic motors for driving respectively said spinner means and said feeding means, first and second pressure compensated flow control valve arrangements each with an adjustable orifice control means for controlling the flow of hydraulic fluid respectively to said first and second motors, means for supplying hydraulic fluid under pressure to said two control valve arrangements, first and second electrically operable position actuators coupled respectively to the corresponding orifice control means of said first and second valve arrangements for independently adjusting the orifice therein, first and second control circuits coupled respectiVely to said first and second position actuators for supplying operating current thereto, first signal producing means responsive to operation of said second hydraulic motor for generating a first electric signal having a parameter proportional to the speed of rotation of said second motor, second signal producing means for producing a second electric signal having a parameter proportional to the ground speed of said vehicular spreader, means coupling said first and second signals to said second control circuit for adjusting said second valve arrangement in a manner tending to maintain said parameters of said two signals in a predetermined ratio, adjustable signal producing means coupled to said first control circuit for applying a control signal thereto for adjusting said first valve arrangement to determine the operating speed of said spinner means, means interconnecting said adjustable signal producing means with one of said first and second signal producing means for simultaneously changing said predetermined ratio upon change in adjustment of said adjustable signal producing means, said simultaneous change being in a direction tending to maintain constant the density at which material is spread independent of change in speed of said spinner means, and compensating means for compensating for differences between the response characteristics of the overall apparatus for feeding material and the overall apparatus for spreading the material.

Claim 19

Apparatus for controlling the operation of a vehicular material spreader having means for feeding material from a reservoir at a controllable rate and spinner means for spreading the material supplied by the feeding means over a controllable area, said apparatus comprising in combination: first and second rotary hydraulic motors for driving respectively said spinner means and said feeding means, first and second pressure compensated flow control valve arrangements each with an adjustable orifice control means for controlling the flow of hydraulic fluid respectively to said first and second motors, means for supplying hydraulic fluid under pressure to said two control valve arrangements, first and second electrically operable position actuators coupled respectively to the corresponding orifice control means of said first and second valve arrangements for independently adjusting the orifice therein, first and second control circuits coupled respectiVely to said first and second position actuators for supplying operating current thereto, first signal producing means responsive to operation of said second hydraulic motor for generating a first electric signal having a parameter proportional to the speed of rotation of said second motor, second signal producing means for producing a second electric signal having a parameter proportional to the ground speed of said vehicular spreader, means coupling said first and second signals to said second control circuit for adjusting said second valve arrangement in a manner tending to maintain said parameters of said two signals in a predetermined ratio, adjustable signal producing means coupled to said first control circuit for applying a control signal thereto for adjusting said first valve arrangement to determine the operating speed of said spinner means, means interconnecting said adjustable signal producing means with one of said first and second signal producing means for simultaneously changing said predetermined ratio upon change in adjustment of said adjustable signal producing means, said simultaneous change being in a direction tending to maintain constant the density at which material is spread independent of change in speed of said spinner means, and compensating means for compensating for differences between the response characteristics of the overall apparatus for feeding material and the overall apparatus for spreading the material.

Claim 20

Apparatus according to claim 15, wherein said compensating means comprises an adjustable orifice control means for said first valve arrangement having a linear response characteristic, in combination with an adjustable orifice control means for said second valve arrangement having a non-linear response which varies at a low rate for low flow rates and at a higher rate for high flow rates.

Claim 21

Apparatus according to claim 15, wherein said compensating means comprises a non-linear potentiometer in said adjustable signal producing means having its slider positioned by said interconnecting means for compensating for non-linearity in the operation of said spinner means.