US 11,808,377 B2
System and methods for operating a solenoid valve
Kale Schrader, Hiawatha, KS (US)
Assigned to Capstan Ag Systems, Inc., Topeka, KS (US)
Filed by Capstan Ag Systems, Inc., Topeka, KS (US)
Filed on Jun. 3, 2021, as Appl. No. 17/303,641.
Claims priority of provisional application 62/704,932, filed on Jun. 3, 2020.
Prior Publication US 2021/0381617 A1, Dec. 9, 2021
Int. Cl. F16K 31/06 (2006.01); H01F 7/18 (2006.01); A01C 23/00 (2006.01)
CPC F16K 31/0679 (2013.01) [H01F 7/1816 (2013.01); A01C 23/007 (2013.01); H01F 2007/1822 (2013.01); H01F 2007/1888 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet configured to translate therein, said drive circuit comprising:
a supply bus configured to couple the solenoid coil to a power supply and supply a coil current;
a return bus configured to provide a ground path for the coil current;
a flyback circuit coupled in parallel to only the solenoid coil, said flyback circuit comprising only a bipolar diode;
a switch coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to said return bus; and
a charge pump circuit having at least one capacitor, said charge pump circuit configured to charge said at least one capacitor using the coil current through the solenoid valve,
wherein said charge pump circuit is further configured to momentarily change a reference of said at least one capacitor coupled in series with the solenoid coil to boost a voltage applied across the solenoid coil when said switch is opened in order to accelerate a decrease in the coil current through the solenoid coil.