Abstract: A torsion isolator assembly (30) for reducing driveline torsionals includes a vane damper (36) including improved valving (40d, 40e) for increasing the damping factor of the damper, improved spiral springs (32,34 or 80,82) for reducing spring stress primarily due to centrifugal forces, and cam surfaces (44d,44c) for further reducing spring stress due to centrifugal forces.

Abstract: A rotary blower (11) of the backflow type is disclosed including a housing portion (50), an inlet end wall portion (49), and a bearing plate (15), the housing portion defining cylindrical chambers (31,33) within which are disposed meshed rotors (35,37). The inlet end wall portion (49) defines an inlet port (51), and the housing portion (50) defines an outlet port (53) including a port end surface (59). The bearing plate (15) defines an end surface (29) and a relief chamber including a relief surface (29R), and the port end surface (59) is disposed in a plane defined by the relief surface (29R). As a result, resistance to the transfer of air through the blower is reduced, thus reducing required drive horsepower, and increasing the isentropic efficiency of the blower.

Abstract: A torsional isolator assembly for reducing driveline torsionals includes a vane damper (36) having valving (40d,40e or 161,163) and chamfers (200,201) on pistons (60 or 160). These chamfers (200,201) aid in forming a seal between a surface (42d or 142d) by creating a hydrodynamic film that biases the piston (60 or 160) toward the housing surface (42d or 142d).