Fluid sprayer system using modulated control valve and a positive displacement pump

A system for mitigating pressure changes in a spray system comprising:

• a control system having a plurality inputs and at least one square wave signal output;
• a speed sensor connected to one of said inputs;
• a flow meter connected to one of said inputs;
• a plurality of flow nozzles associated with at least one of said inputs;
• a positive displacement pump associated with said spray system and having an outlet in selective fluid communication with said flow nozzles;
• and
• a control valve linked to said positive displacement pump, said control valve connected to said square wave output of said control system;
• said control system having a routine wherein a speed of said positive displacement pump is changed by said control valve via an adjustment of a square wave signal delivered from said control system to said valve, said change being proportional to a sensed change in at least one of said inputs of said control system, and wherein said routine comprises an open loop subroutine which executes immediately upon the occurrence of said sensed change.

A method for mitigating pressure changes in a chemical sprayer system comprising:

• monitoring a plurality of spray parameters in said sprayer system;
• controlling a positive displacement pump using a valve controlled by a square wave signal;
• and
• adjusting the square wave signal to said valve with an open loop subroutine immediately upon detection of a change in the state of at least one of said spray parameters, said adjustment being directly proportional to a target speed of said displacement pump, said target speed being selected based on said detected change in state.

A method for mitigating pressure changes in a chemical sprayer system comprising:

• monitoring a plurality of spray parameters in said sprayer system;
• controlling a positive displacement pump using a valve controlled by a square wave signal;
• adjusting the square wave signal to said valve upon detection of a change in the state of at least one of said spray parameters, said adjustment being directly proportional to a target speed of said displacement pump, said target speed being selected based on said detected change in state,
• wherein said detection of a change in state is the detection of a change in the state of a boom control valve of said sprayer system;
• wherein adjusting of the square wave signal takes place prior to finalization of said change in state of said boom control valve of said sprayer system;
• and
• wherein said adjustment to said square wave is proportional to a ratio of nozzles continuing to accept flow after said change in state of said control valve to nozzles no longer accepting flow after said change in sate of said control valve.