Hydraulic system and piston filling control
AssigneeDana Italia S.R.L.
InventorsMario Gelmini, Pier Paolo Rinaldi
Life of this patent
Estimating the term…
Abstract
Methods and systems for a transmission are provided. The method includes estimating a stroke position of the hydraulic control piston based on a pressure of a fluid in a hydraulic line and a valve and a coefficient of the hydraulic line, where the hydraulic line is coupled to a chamber of the hydraulic control piston. The method further includes controlling a pressure of fluid delivered from the valve to the hydraulic control piston based on the estimated stroke position to achieve a piston stroke set-point during a filling phase.
Claims20
A method for operation of a hydraulic control piston in a transmission clutch, comprising:
- estimating a stroke position of the hydraulic control piston based on:
- a pressure of a fluid in a hydraulic line coupled to a chamber of the hydraulic control piston and a valve;
- a clutch coefficient associated with the transmission clutch;
- and
- a coefficient of the hydraulic line;
- and
- controlling a pressure of the fluid delivered from the valve to the hydraulic control piston based on the estimated stroke position to achieve a piston stroke set-point during a filling phase.
A clutch assembly in an automatic transmission, comprising:
- a control valve designed to adjust a pressure of a fluid in a hydraulic line that extends between the control valve and a chamber of a hydraulic control piston;
- a shaft coupled to the hydraulic control piston and a plurality of clutch plates in a clutch;
- and
- a controller including:
- instructions that when executed, during a filling phase, cause the controller to:
- estimate a stroke position of the hydraulic control piston based on a pressure of the fluid in the hydraulic line, a clutch coefficient of the clutch, and a coefficient of the hydraulic line;
- and
- control a pressure of the fluid delivered from the control valve to the hydraulic control piston based on the estimated stroke position to achieve a piston stroke set-point;
- wherein the clutch coefficient is a calibrated value that is determined based on hardware dispersion.
A method for operation of a hydraulic control piston in a clutch of an automatic transmission, comprising:
- in real time or near real time, estimating a stroke position of the hydraulic control piston based on a pressure of a fluid in a hydraulic line, a nominal piston stroke value, a piston end stroke pressure, a clutch coefficient of the clutch, and a coefficient of the hydraulic line;
- and
- controlling the pressure of the fluid delivered from a valve to the hydraulic control piston based on the estimated stroke position to achieve piston stroke set-point;
- wherein the hydraulic line extends between a chamber of the hydraulic control piston and the valve;
- wherein the clutch coefficient is a calibrated value that is determined based on hardware dispersion.
Dependencies are inferred from the claim text.