Apparatus for measuring the strength of a bond between two pieces of material

Claim 1

APPARATUS FOR MEASURING THE STRENGTH OF A BOND BETWEEN TWO PIECES OF MATERIAL WHICH COMPRISES: A STATOR INCLUDING A FIELD WINDING IN HOLLOW COIL FORM AND A STATIONARY MASS OF MAGNETIZABLE MATERIAL ENCOMPASSED BY THE FIELD WINDING; A ROTOR MOUNTED FOR ROTATION WITHIN THE FIELD WINDING OF THE STATOR, SAID ROTOR INCLUDING A ROTATABLE SHAFT AND A MOVABLE MASS OF MAGNETIZABLE MATERIAL ATTACHED TO THE SHAFT IN ECCENTRIC RELATION TO THE ROTATIONAL AXIS OF THE SHAFT; MEANS FOR ENERGIZING SAID FIELD WINDING TO PRODUCE A MAGNETIC FIELD WITHIN A REGION INCLUDING THE TWO MASSES OF MAGNETIZABLE MATERIAL SUCH THAT SAID MASSES ARE MAGNETIZED WITH THE SAME POLARITY AND TEND TO REPEL EACH OTHER; MEANS FOR BIASING THE ROTOR TO A PREDETERMINED ANGULAR POSITION WHEN THE FIELD WINDING IS DE-ENERGIZED, IN WHICH POSITION THE TWO MASSES ARE IN RELATIVELY CLOSE PROXIMITY BUT ANGULARLY OFFSET FROM ONE ANOTHER SO THAT UPON ENERGIZATION OF THE FIELD WINDING A TORQUE TENDING TO ROTATE THE SHAFT RESULTS FROM THE REPULSION BETWEEN THE MAGNETIZED MASSES; MEANS FOR FIXEDLY SUPPORTING TWO PIECES OF MATERIAL BONDED TO EACH OTHER ADJACENT TO THE SHAFT; AN ARM SECURED TO SAID SHAFT AND EXTENDING GENERALLY RADIALLY THEREFROM, SAID ARM HAVING A FREE END THEREOF ARRANGED TO ENGAGE ONE OF SAID TWO BONDED PIECES OF MATERIAL AND TO EXERT A FORCE ON THE BOND BETWEEN SAID TWO PIECES OF MATERIAL WHEN THE TORQUE IS APPLIED TO THE SHAFT; MEANS FOR VARYING THE MAGNITUDE OF THE CURRENT SUPPLIED BY THE FIELD ENERGIZING MEANS TO VARY THE RESULTANT TORQUE APPLIED TO THE SHAFT; AND A METER RESPONSIVE TO THE CURRENT SUPPLIED TO THE FIELD WINDING, SAID METER BEING CALIBRATED TO INDICATE DIRECTLY THE MAGNITUDE OF THE FORCE APPLIED TO THE BOND.