US 12,471,537 B2
Hydraulic motor control system and method
Steven D. Wallestad, Ankeny, IA (US); Mark A. Cracraft, Johnston, IA (US); and James T. Noonan, Bondurant, IA (US)
Assigned to Deere & Company, Moline, IL (US)
Filed by DEERE & COMPANY, Moline, IL (US)
Filed on Jun. 16, 2021, as Appl. No. 17/349,463.
Claims priority of provisional application 63/059,646, filed on Jul. 31, 2020.
Prior Publication US 2022/0030772 A1, Feb. 3, 2022
Int. Cl. F04B 19/04 (2006.01); A01D 46/08 (2006.01); A01F 15/08 (2006.01); A01F 15/10 (2006.01); F04B 23/04 (2006.01); F04B 49/20 (2006.01)
CPC A01F 15/085 (2013.01) [A01D 46/08 (2013.01); A01F 15/106 (2013.01); F04B 19/04 (2013.01); F04B 23/04 (2013.01); F04B 49/20 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A work machine comprising:
a first pump;
a first motor fluidly coupled to the first pump;
a first subassembly coupled to and driven by the first motor;
a first rate-control valve fluidly coupled to the first pump and the first motor and movable through a range of positions to adjust a flow rate to the first motor;
a controller operatively coupled to the first rate-control valve and configured to output current-adjustment signals to the first rate-control valve to adjust a present position of the first rate-control valve;
a primary motor engagement valve fluidly coupled to the first pump and the first motor; and
a secondary motor engagement valve fluidly coupled to the first pump and the first motor and configured to move from a closed position to an open position in response to movement of the primary motor engagement valve to facilitate fluid flow to the first rate-control valve;
wherein a speed of the first motor is proportional to the present position of the first rate-control valve.