US 12,215,779 B2
Hydraulic system with smart relief valve and valve control method
Mario Gelmini, Arco (IT); and Lorenzo Dalla Palma, Arco (IT)
Assigned to DANA ITALIA S.R.L., Arco (IT)
Filed by DANA ITALIA S.R.L., Trentino (IT)
Filed on Jun. 26, 2023, as Appl. No. 18/341,129.
Application 18/341,129 is a continuation of application No. 17/445,813, filed on Aug. 24, 2021, granted, now 11,725,725.
Prior Publication US 2023/0332683 A1, Oct. 19, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. F16H 61/02 (2006.01); F16H 61/00 (2006.01); F16H 61/66 (2006.01)
CPC F16H 61/0206 (2013.01) [F16H 61/0025 (2013.01); F16H 61/66 (2013.01); F16H 2061/0209 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A transmission system, comprising:
a boost pump;
a relief valve in fluidic communication with the boost pump and a reservoir;
a plurality of control valves in fluidic communication with the boost pump, positioned downstream of the relief valve, and in fluidic communication with a plurality of hydraulic devices; and
a controller including:
instructions that when executed, during transmission operation, cause the controller to:
actively adjust a position of the relief valve based on an aggregate hydraulic pressure demand of the plurality of hydraulic devices to alter a boost pressure of a hydraulic fluid supplied to the plurality of control valves; and
instructions that when executed, during an engine cranking event, cause the controller to:
operate the relief valve to decrease the boost pressure to a lower pressure.