Valving for vane damper

DETAILED DESCRIPTION An object of this invention is to provide a torsion damper device having an improved damping factor.
According to a feature of this invention, a torsion assembly is adapted to be disposed for rotation about an axis in a driveline torque converter housing filled with an incompressible torque converter fluid.
The assembly is immersed in the fluid and is drivingly connected between first and second rotatably mounted drives.
The assembly comprises resilient means for transmitting driveline torque between the drives and a hydraulic coupling for damping torque fluctuations in response to flexing of the resilient means.
The coupling includes first and second relatively rotatable housing means defining an annular chamber having radially spaced apart cylindrical surfaces and first and second axially spaced apart end surfaces.
The cylindrical surfaces and the first end surfaces are defined by the first housing means.
Circumferentially spaced apart walls are sealing fixed to the first housing means and extend radially and axially across the annular chamber for dividing the annular chamber into at least two independent arcuate chambers.
A piston is disposed in each arcuate chamber for driving each arcuate chamber into pairs of first and second volumes which vary inversely in volume in response to movement of the pistons relative to the first housing means.
Each piston has radially oppositely facing surfaces in sliding sealing relation with the chamber cylindrical surfaces and has first and second axially oppositely facing end surfaces in sliding sealing relation respectively with the first and second end surfaces of chamber.
The second housing means includes an annular radially extending housing member having an axially facing surface defining the second end surface of the annular chamber.
The housing member second end surface is in sliding sealing relation with each piston second end surface.
The housing member is in sliding sealing relation with portions of the first housing means, is retained against axial movement in a direction away from the first surface of the annular chamber by means affixed to the first housing means, and includes a set of circumferentially spaced and axially extending through openings