Yieldable drive connection for lawn mowers and the like

Claim 1

A YIELDABLE DRIVE CONNECTION FOR COUPLING THE DRIVE SHAFT OF A MOTOR DRIVEN ROTARY LAWN MOVER TO THE CUTTER BLADE THEREOF, SAID CONNECTION COMPRISING A BLOCK HAVING A GENERALLY CIRCULAR CROSS SECTION AND AN AXIAL OPENING TO ACCOMMODATE THE DRIVE SHAFT, A PLURALITY OF OPENINGS IN SAID BLOCK ANNULARLY ARRANGED ABOUT THE AXIS OF SAID DRIVE SHAFT, EACH OPENING HAVING A SLIGHT LIP AT ITS LOWER END, BALLS IN SAID OPENINGS PROJECTING LESS THAN RADIUS DISTANCE BELOW SAID BALLS, SPRING ABOVE SAID BLOCK UNDER COMPRESSION, AN ANNULAR SPACE IN THE UPPER END OF SAID BLOCK, A RETAINING ANNULUS IN SAID SPACE, HOLDING SAID SPRINGS UNDER COMPRESSION ON SAID BALLS INTURNED LIPS FORMED OF METAL SPUN FROM SAID BLOCK OVER THE EDGE OF SAID SPACE AND ENGAGING THE INNER AND OUTER RIMS OF SAID ANNULUS TO POSITIVELY SECURE SAID ANNNULUS IN SAID SPACE AT A PREDETERMINED DEPTH THEREIN, A HUB ON ONE END OF THE BLOCK, AND A CUTTER BLADE HAVNG A PLURALITY OF ANNULARLY ARRANGED OPENINGS IN AXIAL ALIGNMENT WITH THE OPENINGS IN THE BLOCK MOUNTED ON THE HUB, THE BALLS IN THE BLOCK PROJECTING INTO THE OPENINGS IN THE BLADE, WHEREBY SAID BALLS YIELD UPON ENGAGEMENT OF SAID CUTTER BLADE WITH AN OBSTRUCTION TO STOP ROTATION OF SAID BLADE.