Device for checking the contour, especially trochoidal contour surfaces, of work pieces

Claim 1

A CHECKING DEVICE FOR CHECKING THE CONTOUR SURFACE OF A WORK PIECE, ESPECIALLY THE INNER TROCHOIDAL CONTOUR OF A HOUSING FOR A ROTARY PISTON ENGINE, WHICH INCLUDES: A TEMPLATE HAVING AN OUTSIDE CONTOUR SHAPED IN CONFORMITY WITH THE CONTOUR SURFACE OF THE WORK PIECE TO BE CHECKED, MEANS FOR LOCATING SAID TEMPLATE AND A WORK PIECE TO BE CHECKED COAXIALLY WITH REGARD TO EACH OTHER SO THAT THE TEMPLATE WILL BE LOCATED WITHIN AND IN SPACED RELATIONSHIP TO THE CONTOUR OF THE WORK PIECE TO BE CHECKED, AT LEAST ONE ARM PIVOTABLE ABOUT THE COMMON AXIS OF SAID TEMPLATE AND THE WORK PIECE TO BE CHECKED AND EXTENDING RADIALLY FROM SAID COMMON AXIS, TWO FEELER MEMBERS SUPPORTED BY AND DISPLACEABLE ON SAID ARM RADIALLY OF SAID COMMON AXIS, EACH OF SAID TWO FEELER MEMBERS HAVINGY A CURVED CONTACTING SURFACE FOR CONTACTING ENGAGEMENT WITH THE CONTOUR SURFACE OF SAID TEMPLATE AND THE CORRESPONDING CONTOUR SURFACE OF THE WORK PIECE TO BE CHECKED, YIELDABLE MEANS ARRANGED BETWEEN SAID FEELER MEMBERS AND BIASING THE SAME SO AS TO URGE SAID FEELER MEMBERS TO MOVE RELATIVE TO EACCH OTHER IN THE DIRECTION TOWARD SAID TEMPLATE AND THE WORK PIECE TO BE CHECKED RESPECTIVELY, AND INDICATING MEANS RESPONSIVE TO A MOVEMENT OF SAID FEELER MEMBERS RELATIVE TO EACH OTHER FOR INDICATING SUCH RELATIVE MOVEMENT.