Device and method for detecting blockages in an agricultural sprayer

• US 10,209,111 B2
• Filed: 08/31/2017
• Issued: 02/19/2019
• Est. Priority Date: 07/02/2014
• Status: Active Grant

• Current Assignee: Blue Leaf IP Incorporated (CNH Industrial N.V.)
• Original Assignee: CNH Industrial America LLC (CNH Industrial N.V.)
• Inventors: Ni, Bingcheng
• Primary Examiner(s): Boeckmann, Jason
• Assistant Examiner(s): Greenlund, Joseph A
• Application Number:
  US15/692,740
• Publication Number:
  US 20170363454A1
• Time in Patent Office: 537 Days
• Field of Search: 239 1, 239146, 239722, 239 71, 239 74, 34053926, 340603, 340606-608, 370535, 370916
• CPC Class Codes: A01G 25/09 Watering arrangements making use of movable installations on wheels or the like
• CPC Class Codes: A01M 7/0042 Field sprayers, e.g. self-propelled, drawn or tractor-mounted
• CPC Class Codes: A01M 7/0089 Regulating or controlling systems the delivery being related to the movement of a vehicle B05B9/06
• CPC Class Codes: B05B 1/20 Arrangements of several outlets along elongated bodies, e.g. perforated pipes or troughs, e.g. spray booms spray booms for agricultural uses A01M7/0071; spray bars for treating roads E01C19/176; Outlet elements therefor
• CPC Class Codes: B05B 12/008 integrated in or attached to a discharge apparatus, e.g. a spray gun
• CPC Class Codes: B05B 12/085 responsive to flow or pressure of liquid or other fluent material to be discharged B05B1/3006, B05B1/323, B05B7/1254 take precedence
• CPC Class Codes: B05B 15/50 Arrangements for cleaning; Arrangements for preventing deposits, drying-out or blockage; Arrangements for detecting improper discharge caused by the presence of foreign matter
• CPC Class Codes: B05B 15/658 the spraying apparatus or its outlet axis being perpendicular to the flow conduit
• CPC Class Codes: G01F 1/68 by using thermal effects

Abstract

An agricultural sprayer arrangement includes a chassis; a ground engaging traction member carried by the chassis; a liquid tank carried by the chassis; a boom carried by the chassis; a conduit associated with the boom in fluid communication with the liquid tank that acts as a fluid flow path; a nozzle having an inlet in fluid communication with the conduit; a first flow sensor placed upstream of the inlet in the fluid flow path that provides a first flow signal; a second flow sensor placed downstream of the inlet in the fluid flow path that provides a second flow signal; and an electrical processing circuit coupled to the first flow sensor and the second flow sensor that is configured to compare the first and second flow signals to determine a flow rate decrease and issue an alarm if the flow rate decrease is less than a predetermined threshold level.

Claims

1. A method for detecting a blockage in an agricultural sprayer, comprising the steps of:

providing a sprayer that includes a chassis, at least one ground engaging traction member carried by the chassis, a liquid tank carried by the chassis, a boom carried by the chassis, a fluid conduit associated with the boom in fluid communication with the liquid tank and configured as a flow fluid path, a pump configured to produce a liquid flow through at least a portion of the fluid conduit from the liquid tank, a nozzle having an inlet that is fluidly connected to the liquid flow in the fluid conduit, a first flow sensor in the liquid flow upstream of the inlet, and a second flow sensor in the liquid flow downstream of the inlet, and an electric processing circuit having a multiplexer coupled to the first flow sensor and the second flow sensor, a frequency converter coupled to the multiplexer, an amplifying filter coupled to the frequency converter, a de-multiplexer coupled to the amplifying filter, and a subtractor coupled to the de-multiplexer;

receiving a first signal from the first flow sensor into the multiplexer, converting the first signal via the frequency converter, amplifying the first signal via the amplifying filter, outputting the amplified first signal to the de-multiplexor, and outputting the first signal from the de-multiplexor to the subtractor;

receiving a second signal from the second flow sensor into the multiplexer, converting the second signal via the frequency converter, amplifying the second signal via the amplifying filter, outputting the amplified second signal to the de-multiplexor, and outputting the second signal from the de-multiplexor to the subtractor;

outputting a differential signal based upon the first signal and the second signal from the subtractor, and sending the differential signal to a display; and

reporting an alarm on the display as a result of the differential signal when the differential signal falls below a predetermined threshold level to indicate a blockage.

2. The method according to claim 1, further including the step of determining a nozzle flow rate based on a flow rate decrease.

3. The method according to claim 2, wherein the predetermined threshold level corresponds to the nozzle flow rate being below a desired level.

4. The method according to claim 3, wherein the desired level is approximately 80% of unobstructed liquid flow through the nozzle.

5. The method according to claim 1, wherein the first flow sensor and the second flow sensor are both thermal dispersion flow sensors.

6. The method according to claim 1, wherein the electrical processing circuit further includes a timing circuit configured to output a clock signal to at least one of the multiplexer and the de-multiplexer.