US 11,052,881 B1
Hydraulic retarding control system
Dayao Chen, Bolingbrook, IL (US); William F. Erdman, Saint Charles, IL (US); and Edward W. Mate, Manhattan, IL (US)
Assigned to Caterpillar Underground Mining Pty. Ltd., Tasmania (AU)
Filed by Caterpillar Underground Mining Pty. Ltd., South Burnie (AU)
Filed on Jul. 23, 2020, as Appl. No. 16/937,160.
Int. Cl. B60T 1/093 (2006.01); F02B 63/06 (2006.01); F15B 13/04 (2006.01); F15B 13/02 (2006.01); E02F 9/22 (2006.01); B60K 31/08 (2006.01); B60T 10/04 (2006.01)
CPC B60T 1/093 (2013.01) [B60K 31/08 (2013.01); B60T 10/04 (2013.01); E02F 9/2235 (2013.01); E02F 9/2267 (2013.01); E02F 9/2296 (2013.01); F02B 63/06 (2013.01); F15B 13/024 (2013.01); F15B 13/0401 (2013.01); E02F 9/2228 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A work machine having an electric drive system, the work machine comprising:
a prime mover;
a machine controller; and
a hydraulic control system, the hydraulic control system including:
a pump, the pump configured to supply pressurized fluid to the hydraulic control system via a supply line,
a control valve fluidly coupled to the pump via the supply line, the control valve including a pressure relief valve, and
a retarding control valve fluidly connected to the pump and the control valve via the supply line, the retarding control valve including a solenoid valve coupled to the machine controller, an orifice restricting a flow of the pressurized fluid through the supply line, and a check valve coupled to a discharge line, the discharge line configured to branch from a point along the supply line between the solenoid valve and the orifice.
 
18. A retarding control valve of a work machine, the retarding control valve comprising:
a proportional solenoid valve coupled to a machine controller, the machine controller configured to determine a retarding requirement and to actuate the solenoid valve based on the determined retarding requirement, the solenoid valve being fluidly coupled to a hydraulic pump via a supply line;
an orifice positioned downstream from the proportional solenoid valve and fluidly connected to the solenoid valve, the orifice restricting a flow of a pressurized fluid through the supply line when the solenoid valve is actuated; and
a spring-loaded check valve coupled to a discharge line, the discharge line configured to branch from a point along the supply line between the solenoid valve and the orifice, the check valve configured to selectively allow a unidirectional flow of the pressurized fluid from the branch point along the supply line to a load sense line.