Patent ID: 9587684
Date: 2017-03-07
CPC Classifications: F16D

Claim:
1. A method of regulating a clutch assembly in an automatic transmission having a hydraulic circuit configured to vary a fluid line pressure, the clutch assembly having a set of clutch plates and a clutch piston with a fluid seal, the method comprising: commanding, via a controller, the hydraulic circuit to apply a first hydraulic force to the clutch piston to displace the clutch piston relative to the set of clutch plates and thereby affect a shift between speed-ratios in the transmission; determining, via the controller, a drag force of the fluid seal; determining, via the controller, a velocity of the displaced clutch piston relative to the set of clutch plates that results from the determined drag force of the fluid seal acting counter to the displacement of the clutch piston; and regulating the clutch assembly to compensate for the determined drag force of the fluid seal acting counter to the displacement of the clutch piston.