High accuracy automatically controlled variable linear seed spacing planting apparatus

• US 5,598,794 A
• Filed: 02/13/1995
• Issued: 02/04/1997
• Est. Priority Date: 02/13/1995
• Status: Expired due to Fees

• Current Assignee: Parker Hannifin Customer Support, Inc.
• Original Assignee: Fluid Power Industries, Inc.
• Inventors: Harms, Louis C., Rosenbrock, Richard
• Primary Examiner(s): Melius, Terry Lee
• Assistant Examiner(s): Novosad, Christopher J.
• Application Number:
  US08/388,214
• Time in Patent Office: 722 Days
• Field of Search: 111/200, 111/177, 111/178, 111/903, 111/904, 111/921, 111/922, 364/424.07
• US Class Current: 111/177
• CPC Class Codes: A01C 7/102 Regulating or controlling the seed rate
• CPC Class Codes: Y10S 111/903 Monitor
• CPC Class Codes: Y10S 111/904 Population control function
• CPC Class Codes: Y10S 111/922 Variable drive mechanism

Abstract

A control system for a mobile planting apparatus which permits discrete plant spacing to be determined and maintained independent of any wheel rotation on the planting apparatus or towing apparatus is disclosed, having: (1) a ground speed sensor wherein the rate of movement relative to the ground is determined independent of wheel rotation of the planting apparatus or towing apparatus; (2) an input/display device for inputting desired linear plant spacing; (3) a variable speed motor for mechanically driving seed metering devices on the planting apparatus at varying rates independent of any wheel rotation of the planting apparatus or towing apparatus, wherein the motor changes speeds in response to an electronic signal; (4) a programmable control circuit communicating electronically with the input/display device and ground speed sensor, wherein the programmable control circuit: (a) determines the number of seeds to be dispensed per linear unit of distance traveled based upon the desired spacing received from the input/display device; (b) determines the number of linear units of distance traveled based upon electronic signals from the ground speed sensor; and (c) determines the rate at which the variable speed motor should operate in order to dispense seeds to achieve the desired linear plant spacing, and sends an electronic signal to the variable speed motor to cause the motor to operate at the rate necessary to cause the seed metering devices to dispense seeds so as to achieve the desired linear plant spacing.

Claims

1. A control system for a mobile planting permitting discrete plant spacing to be determined and maintained independent of any wheel rotation on said planting apparatus or any towing apparatus, comprising;

(A) a ground speed sensor wherein the rate of movement relative to the ground is determined independent of wheel rotation of said planting apparatus or of wheel rotation of any towing apparatus, wherein said ground speed sensor is a Doppler effect radar;

(B) an input display device for inputting desired linear planting spacing;

(C) a variation speed motor for mechanically driving seed metering devices on said planting apparatus at varying rates independent of any wheel rotation of said planting apparatus or of said towing apparatus, wherein said variable speed motor is capable of changing speeds directly or indirectly in response to an electronic signal; and

(D) a programmable control circuit which communicates electronically with said input/display device, and with said ground speed sensor, wherein said programmable control circuit;

(i) determines the discrete number of seeds to be dispensed by said seed metering devices per linear unit of distance traveled by said planting apparatus based upon the desired linear plant spacing received from the input/display device;

(ii) determines directly or indirectly the number of units of distance traveled by the planting apparatus based upon electronic communications received form said ground speed sensor; and

(iii) determines the rate at which said variable speed motor should operate in order to cause said seed metering devices to dispense seeds to achieve said desired linear plant spacing per linear unit of distance traveled by said planting apparatus, and further determines and sends an electronic signal in order to directly or indirectly cause the rate of said variable speed motor to vary in order to correspond to said determined rate at which said variable speed motor is to operate in order to cause said seed metering devices to dispense seeds in order to achieve said desired linear planting spacing;

wherein, interposed between said ground speed sensor and said programmable control circuit, and in electronic communication with both, is a signal conditioning circuit.

2. The control system for a mobile planting apparatus of claim 1 wherein said signal conditioning circuit is capable of refining said electronic communications from said ground speed sensor such that ground speed may be accurately determined to within 0.01 miles per hour or less based upon the aforesaid refined electronic communications from said ground speed sensor and said signal conditioning circuit.

3. The control system for a mobile planting apparatus of claim 1 wherein said input/display device is capable of being operated while said planting apparatus is in motion, permitting linear plant spacing to be varied while said planting apparatus is in motion.

4. The control system for a mobile planting apparatus of claim 3 further comprising an active speed sensor for sensing directly or indirectly the rate at which said variable speed motor is operating to cause said seed metering devices to dispense seeds, and which communicates electronically with said programmable control circuit, wherein said programmable control circuit further determines whether the electronic signal from the active speed sensor indicates whether the rate at which said variable speed motor is operating to cause said seed metering devices to dispense seeds corresponds to said determined rate at which said variable speed motor is to operate in order to achieve said desired linear plant spacing, and, if not, sends an electronic signal in order to directly or indirectly cause the rate of operation of said variable speed motor to vary in order to correspond to said determined rate at which said variable speed motor is to operate in order to achieve said desired linear plant spacing.

5. The control system for a mobile planting apparatus of claim 4 wherein said variable speed motor is a hydraulic motor.

6. The control system for a mobile planting apparatus of claim 5 further comprising a hydraulic motor circuit, said hydraulic motor circuit comprising:

(A) a hydraulic pump;

(B) the aforesaid hydraulic motor;

(C) a hydraulic proportional valve interposed between said hydraulic pump and said hydraulic motor, and in hydraulic communication with both, said hydraulic proportional valve being in electronic communication with said programmable control circuit and responsive thereto, wherein said hydraulic proportional valve is designed to proportionally open, close, or maintain its then-current hydraulic valve opening in response to said electronic communications from said programmable control circuit to said hydraulic proportional valve.

7. The control system for a mobile planting apparatus of claim 6 wherein said hydraulic motor circuit further comprises a safety valve interposed between said hydraulic pump and said hydraulic motor, said hydraulic safety valve being in electronic communication with said programmable control circuit and responsive thereto, wherein said hydraulic safety valve opens to allow hydraulic fluid to pass therethrough in response to an electronic signal from said programmable control circuit when said programmable control circuit determines that said planting apparatus is moving in a positive direction relative to the ground as a result of electronic communications from said ground speed sensor, and said hydraulic safety valve closes in response to an electronic signal from said programmable control circuit when said programmable control circuit determines that said planting apparatus is not moving in a positive direction relative to the ground as a result of electronic communications from said ground speed sensor.

8. The control system for a mobile planting apparatus of claim 7 wherein said hydraulic motor circuit further comprises hydraulic communications capable of returning hydraulic fluid directly or indirectly to the hydraulic pump, wherein said hydraulic fluid to be returned to said hydraulic pump is hydraulic fluid:

(A) which has passed through said hydraulic motor;

or

(B) which has not passed through said hydraulic safety valve as a result of said hydraulic safety valve being closed;

or

(C) which has not passed through said hydraulic proportional valve as a result of said hydraulic proportional valve being partially or fully closed.

9. The control system for a mobile planting apparatus of claim 8 wherein said signal conditioning circuit further comprises a phase-locked loop including a voltage controlled oscillator.

10. The control system for a mobile planting apparatus of claim 9 wherein said signal conditioning circuit further comprises electronic communications for preventing the operating frequency of the voltage controlled oscillator from migrating in the event that the electronic communications from the ground speed sensor intermittently fade or disappear.

11. The control system for a mobile planting apparatus of claim 10 wherein said signal conditioning circuit further comprises:

(A) an electronic signal squaring circuit and a phase detector circuit in electronic communication with said ground speed sensor; and

(B) a positive and a negative signal magnitude threshold comparator circuit, with the electronic outputs of both threshold comparator circuits combined to gate the outputs to a loop filter circuit when the absolute value of the electronic signal so conditioned is above a predetermined level, and in electronic communication with said voltage controlled oscillator via said loop filter circuit, and wherein said loop filter circuit controls the frequency of the electronic signal of the aforesaid voltage controlled oscillator.

12. The control system for a mobile planting apparatus of claim 11 wherein said ground speed sensor is mounted on said planting apparatus.

13. The control system for a mobile planting apparatus of claim 11 wherein said ground speed sensor is mounted on said towing apparatus.

14. The control system for a mobile planting apparatus of claim 11 wherein said input/display device further comprises inputs for inputting the number of seeds planted per rotation of said seed metering devices, and wherein that input is electronically communicated to said programmable control circuit.

15. The control system for a mobile planting apparatus of claim 14 wherein said input/display device further comprises a display that shows the desired linear plant spacing.

16. The control system for a mobile planting apparatus of claim 15 wherein said input/display device further comprises a display that shows the number of seeds to be planted per rotation of said seed metering devices.

17. A mobile planting apparatus for planting discrete number of seeds per unit of distance traveled independent of any wheel rotation of said planting apparatus, or of any towing apparatus, comprising:

(A) a frame;

(B) one or more seed dispensers mounted on said frame, wherein said seed dispensers further comprise seed metering devices;

(C) a ground speed sensor wherein ground speed is determined independent of any wheel rotation of said planting apparatus or of any wheel rotation of any towing apparatus, wherein said ground speed sensor is a Doppler effect radar;

(D) a variable speed motor mechanically connected to said seed dispensers, and capable of driving said seed metering devices at varying rates, wherein, as the motor drives the seed metering devices at faster rate, the discrete number of seeds dispensed by the seed metering devices per unit of time is increased, and wherein said variable speed motor changes speeds directly or indirectly in response to an electronic signal;

(E) an input/display device for inputting desired linear plant spacing;

(F) a programmable control circuit which communicates electronically with said input/display device, and said ground speed sensor, wherein said programmable control circuit;

(i) determines the discrete number of seeds to be dispensed by said seed metering devices per linear unit of distance traveled by said planting apparatus based upon the desired linear planting spacing electronic communication received from the input/display device;

(ii) determines directly or indirectly the number of units of distance traveled by the planting apparatus based upon electronic communication received from said ground speed sensor; and

(iii) determiners the rate at which said variable speed motor should operate in order to cause said seed metering devices to dispense seeds in order to achieve said desired linear plant spacing per linear unit of distance traveled by said planting apparatus, and further determines and sends an electronic signal in order to directly or indirectly cause the rate of said variable speed motor to vary in order to correspond to said determined rate at which said variable speed motor is to operate in order to cause said seed metering devices to dispense seeds in order to achieve said desired linear plant spacing;

wherein, interposed between said ground speed sensor and said programmable control circuit, and in electronic communication with both, is a signal conditioning circuit.

18. The mobile planting apparatus of claim 17 further comprising an active speed sensor for sensing directly or indirectly the rate at which said variable speed motor is operating to cause said seed metering devices to dispense seeds, and which communicates electronically with said programmable control circuit, wherein said programmable control circuit further determines whether the electronic signal from the active speed sensor indicates whether the rate at which said variable speed motor is operating to cause said seed metering devices to dispense seeds corresponds to said determined rate at which said variable speed motor is to operate in order to achieve said desired linear plant spacing, and, if not, sends an electronic signal in order to directly or indirectly cause the rate of operation of said variable speed motor to vary in order to correspond to said determined rate at which said variable speed motor is to operate in order to achieve said desired linear plant spacing.

19. The mobile planting apparatus of claim 18 wherein said variable speed motor is a hydraulic motor, and wherein said mobile planting apparatus further comprises a hydraulic motor circuit, said hydraulic motor circuit comprising:

(A) a hydraulic pump;

(B) the aforesaid hydraulic motor;

(C) a hydraulic proportional valve interposed between said hydraulic pump and said hydraulic motor, and in hydraulic communication with both, said hydraulic proportional valve being in electronic communication with said programmable control circuit and responsive thereto, wherein said hydraulic proportional valve is designed to proportionally open, close, or maintain its then-current hydraulic valve opening in response to said electronic communications from said programmable control circuit to said hydraulic proportional valve.

20. The control system for a mobile planting apparatus of claim 19 wherein said hydraulic motor circuit further comprises a safety valve interposed between said hydraulic pump and said hydraulic motor, said hydraulic safety valve being in electronic communication with said programmable control circuit and responsive thereto, wherein said hydraulic safety valve opens to allow hydraulic fluid to pass therethrough in response to an electronic signal from said programmable control circuit when said programmable control circuit determines that said planting apparatus is moving in a positive direction relative to the ground as a result of electronic communication from said ground speed sensor, and said hydraulic safety valve closes in response to an electronic signal from said programmable control circuit when said programmable control circuit determines that said planting apparatus is not moving in a positive direction relative to the ground as a result of electronic communications from said ground speed sensor.

21. The mobile planting apparatus of claim 20 wherein said signal conditioning circuit further comprises a phase-locked loop including a voltage controlled oscillator.

22. The mobile planting apparatus of claim 21 wherein said signal conditioning circuit further comprises electronic communications for preventing the operating frequency of the voltage controlled oscillator from migrating in the event that the electronic communications from the ground speed sensor intermittently fade or disappear.

23. The mobile planting apparatus of claim 22 wherein said signal conditioning circuit further comprises:

(A) an electronic signal squaring circuit and a phase detector circuit in electronic communication with said ground speed sensor; and

(B) a positive and a negative signal magnitude threshold comparator circuit, with the electronic outputs of both threshold comparator circuits combined to gate the outputs to a loop filter circuit when the absolute value of the electronic signal so conditioned is above a predetermined level, and in electronic communication with said voltage controlled oscillator via said loop filter circuit, and wherein said loop filter controls the frequency of the electronic signal of the aforesaid voltage controlled oscillator.

24. The mobile planting apparatus of claim 23 wherein said input/display device further comprises:

(A) inputs for inputting the number of seeds planted per rotation of said seed metering devices;

(B) a display which shows the desired linear plant spacing; and

(C) a display which shows the number of seeds to be planted per rotation of said seed metering devices.

25. The mobile planting apparatus of claim 24 wherein said input/display device permits the desired plant spacing to be changed while the planting apparatus is in motion.