COMPENSATION FOR A DRAG FORCE GENERATED BY A ROTATING CLUTCH PISTON SEAL

摘要

A method of regulating a clutch assembly that has a set of clutch plates and a clutch piston with a fluid seal in an automatic transmission that includes a hydraulic circuit is disclosed. The method includes commanding the hydraulic circuit via the controller to apply a first hydraulic force to the clutch piston to displace the clutch piston relative to the set of clutch plates in order to affect a shift between speed-ratios in the transmission. The method also includes determining a drag force of the fluid seal. The method also includes determining a velocity of the displaced clutch piston that results from the drag force of the fluid seal acting counter to the displacement of the clutch piston. The method additionally includes regulating the clutch assembly to compensate for the determined drag force of the fluid seal acting counter to the displacement of the clutch piston.

主权项

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.