Flexible coupling for absorbing axial and rotational impact

Claim 1

A flexible coupling comprising: an outer tube; an inner tube located within said outer tube; a substantially cylindrically shaped elastic body connecting said inner tube and said outer tube in the diametrical direction, said outer tube, inner tube and elastic body having a common central axis; a drive shaft attached to one of said inner and outer tubes; a driven shaft attached to the other of said inner and outer tubes, said drive and driven shafts being movable relative to each other in an axial direction due to the elasticity of said elastic body; a sealed fluid chamber formed circumferentially within said elastic body; and means for dividing said fluid chamber into first and second circumferentially-extending sections connected by a narrow communication channel and for causing a fluid contained in said first and second sections to flow circumferentially from one to the other through the narrow channel in response to relative rotational movement of said inner and outer tubes, said dividing and flow causing means comprising a protruding member provided in said fluid chamber, said protruding member being integrally attached at a base end to said elastic body on one side of said fluid chamber and being free at its distal end such as to be movable about the central axis in response to relative rotation of said inner and outer tubes and due to resiliency of the elastic body, said protruding member extending radially through said fluid chamber and terminating at its distal end near the opposite side of said fluid chamber to divide the fluid chamber into said first and second sections and to form said narrow communication channel.