Swinging key lever tumbler lock

Claim 1

IN A LOCK MECHANISM OF THE CHARACTER DESCRIBED: (A) A CYLINDER BODY MOUNTED FOR ROTATION ABOUT ITS AXIS AND HAVING THEREIN AN OUTWARDLY OPENING TUMBLER CAVITY AND A KEY RECEIVING APERTURE; (B) A LOCKING BAR MOUNTED IN THE CYLINDER BODY FOR BODILY MOTION RELATIVE TO THE CYLINDER BODY BETWEEN PROJECTED AND RETRACTED POSITIONS; (C) A PLURALITY OF TUMBLERS IN THE CYLINDER BODY, EACH HAVING A ROUNDED PROJECTION ON ONE END PORTION RECEIVED IN A SOCKET IN THE CYLINDER BODY THAT OPENS TO SAID CAVITY BY WHICH THE TUMBLER IS MOUNTED FOR SWINGING MOTION ACROSS THE KEY APERTURE BETWEEN LOCKING AND UNLOCKING POSITIONS, SAID TUMBLERS COOPERATING WITH THE LOCKING BAR TO HOLD THE LATTER IN ITS PROJECTED POSITION WHEN THE TUMBLERS ARE IN THEIR LOCKING POSITIONS AND TO RELEASE THE LOCKING BAR FOR MOVEMENT TO ITS RETRACTED POSITION WHEN THE TUMBLERS ARE SWUNG TO THEIR UNLOCKING POSITIONS BY A PROPER KEY RECEIVED IN THE KEY APERTURE; (D) A UNITARY SPRING MEMBER HAVING PORTIONS PROVIDING (1) A BASE PLATE WHICH EXTENDS ACROSS THE MOUTH OF THE CAVITY IN THE CYLINDER BODY TO SUBSTANTIALLY CLOSE THE SAME, (2) TUMBLER RETAINING MEANS COMPRISING AN EXTENSION OF ONE SIDE OF THE BASE PLATE BOWED INTO THE CAVITY AND ENGAGING SAID PROJECTION ON EACH TUMBLER TO HOLD THE SAME SWINGABLY SEATED IN ITS SOCKET, AND (3) A PLURALITY OF ELONGATED, LATERALLY SPACED APART LEAF SPRINGS, ONE FOR EACH TUMBLER, EXTENDING FROM THE OPPOSITE SIDE OF THE BASE PLATE, EACH BOWED INTO THE CAVITY AND OVER THE BASE PLATE AND ENGAGING ITS TUMBLER TO BIAS THE SAME TO ITS LOCKING POSITION; AND (E) COOPERATING MEANS ON THE CYLINDER BODY AND THE SPRING MEMBER FOR SECURING THE LATTER TO THE CYLINDER BODY.