Safety device for screw assembling

Claim 1

A LOCKING DEVICE FOR A THREADED FASTENER USED IN ASSEMBLING A PAIR OF ELEMENTS RELATIVE TO EACH OTHER, COMPRISING, AN INTERLOCKING PAIR OF OPPOSITELY-DISPOSED AND IDENTICAL UPPER AND LOWER RESILIENT DISC-LIKE WASHERS, EACH SAID WASHER INCLUDING AN ANNULAR BODY HAVING A FRONT FACE AND A REAR FACE AND A SERIES OF RADIALLY-EXTENDING NOTCHES EQUISPACED ALONG AND EXTENDING INWARDLY OF ITS OUTER PERIPHERY AND A SERIES OF EQUISPACED CIRCUMFERENTIALLY-ARRANGED CURVED LUGS ALONG CORRESPONDING RADIAL MARGINS OF EACH OF THE NOTCHES AND PROJECTING OUTWARDLY FROM THE PLANE OF THE FRONT FACE, EACH LUG HAVING AN OUTER FREE EXTREMITY EXTENDING RADIALLY WIT RESPECT TO ITS SAID WASHER, THE LUGS OF SAID UPPER WASHER BEING INTERDIGITABLY RECEIVED IN THE NOTCHES OF SAID LOWER WASHER AND HAVING FREE ENDS EXTENDING BEYOND THE PLANE OF THE REAR FACE OF SAID LOWER WASHER AND THE LUGS OF SAID LOWER WASHER BEING INTERDIGITABLY RECEIVED IN THE NOTCHES OF SAID UPPER WASHER AND HAVING FREE ENDS EXTENDING BEYOND THE PLANE OF THE REAR FACE OF SAID UPPER WASHER, THE LUGS OF SAID UPPER AND LOWER WASHERS HAVING BUTTRESSING CONTACT WITH THE RESPECTIVE ADJACENT ONE OF THE ELEMENTS BEING ASSEMBLED AS THE FRONT FACES OF SAID WASHERS ARE BROUGHR INTO CONFRONTING POSITIONS AS TO EACH OTHER IN INTERLOCKED OPERATIVE RELATIONSHIP WITH THE REAR FACES OF ADJACENT PAIRS OF LUGS HAVING AN INCREASING BEARING RELATIONSHIP AS TO EACH OTHER UNDER FLEXURE OF THE LUGS UPON THE APPLICATION OF PRESSURE TO THE LOCKING DEVICE.