Fluid-actuated coupling and wear shoe therein

Claim 1

A FLUID-ACTUATED COUPLING COMPRISING TWO RELATIVELY ROTATABLE STRUCTURES ADAPTED FOR TORQUE-SUSTAINING FRICTIONAL ENGAGEMENT WITH ONE ANOTHER, ONE OF SAID STRUCTURES HAVING AN ACTUATING WALL WHICH IS MOVABLE IN ONE DIRECTION TO BRING SAID STRUCTURES INTO TORQUE-SUSTAINING ENGAGEMENT, THE OTHER OF SAID STRUCTURES HAVING A FRICTIONAL-ENGAGEMENT FACE SPACED IN SAID ONE DIRECTION FROM SAID ACTUATING WALL, SAID ONE STRUCTURE ALSO INCLUDING A PLURALITY OF WEAR SHOES DISPOSED BETWEEN SAID ACTUATING WALL AND SAID FRICTIONAL-ENGAGEMENT FACE ON SAID OTHER STRUCTURE AT SUCCESSIVE LOCATIONS CIRCUMFERENTIALLY AROUND SAID ACTUATING WALL, EACH SAID WEAR SHOE COMPRISING A SUBSTANTIALLY RIGID BACKING PLATE ADJACENT SAID ACTUATING WALL, A SUBSTANTIALLY RIGID SECOND PLATE SPACED IN SAID ONE DIRECTION FROM SAID BACKING PLATE AND DISPOSED CLOSELY ADJACENT SAID FRICTIONAL ENGAGEMENT FACE ON SAID OTHER STRUCTURE, A FRICTION FACING ON SAID SECOND PLATE FOR ENGAGEMENT WITH SAID FRICTIONAL ENGAGEMENT FACE ON SAID OTHER STRUCTURE, AND RUBBER-LIKE MATERIAL SANDWICHED BETWEEN SAID BACKING PLATE AND SAID SECOND PLATE AND BONDED TO BOTH, SAID RUBBER-LIKE MATERIAL HAVING AN APPRECIABLE THICKNESS IN SAID ONE DIRECTION ENABLING IT TO UNDERGO SUBSTANTIAL DEFORMATION CIRCUMFERENTIALLY WHEN STRESSED, SAID BACKING PLATE AND SAID SECOND PLATE THROUGHOUT THEIR RESPECTIVE EXTENTS HAVING A SUBSTANTIAL CIRCUMFERENTIAL CLEARANCE FROM ONE ANOTHER TO ENABLE SUBSTANTIAL CIRCUMFERENTIAL DISPLACEMENT OF SAID SECOND PLATE WITH RESPECT TO SAID BACKING PLATE ALONG WITH CIRCUMFERENTIAL DEFORMATION OF SAID RUBBER-LIKE MATERIAL WHEN SAID RELATIVELY ROTATABLE STRUCTURES ARE BROUGHT INTO TORQUE-SUSTAINING ENGAGEMENT.