Garage door openers

Claim 1

IN AN APPARATUS FOR OPERATING AN OVERHEAD GARAGE DOOR, A ROTATABLY SUPPORTED FIRST SLEEVE, MEANS INCLUDING AN ELECTRIC MOTOR FOR ROTATING SAID SLEEVE, A SECOND SLEEVE SUPPORTED IN AXIAL ALINEMENT WITH SAID FIRST SLEEVE FOR LIMITED SLIDING MOVEMENT AWAY FROM A NORMAL POSITION, A CONNECTION BETWEEN SAID FIRST AND SECOND SLEEVES PROVIDING FOR ROTATABLE DRIVING OF SAID SECOND SLEEVE WHEN SAID FIRST SLEEVE IS ROTATED WHILE PERMITTING AXIAL SLIDING MOVEMENT OF SAID SECOND SLEEVE RELATIVE TO SAID FIRST SLEEVE, A ROD EXTENDING THROUGH SAID FIRST SLEEVE AND CONNECTED TO SAID SECOND SLEEVE FOR ROTATION THEREWITH, A SCREW ON THE INNER END OF SAID ROD, A TRAVELING NUT ON SAID SCREW ADAPTED TO BE CONNECTED TO THE GARAGE DOOR TO OPERATE THE LATTER, AN ELECTRIC SWITCH IN THE CIRCUIT TO SAID MOTOR ENGAGED BY A PORTION OF SAID ROD WHEN SAID SECOND SLEEVE IS IN NORMAL POSITION TO MAINTAIN THE MOTOR CIRCUIT COMPLETE, SAID CONNECTION BETWEEN THE FIRST AND SECOND SLEEVES PERMITTING AXIAL MOVEMENT OF SAID SECOND SLEEVE AND ROD AWAY FROM NORMAL POSITION TO BREAK SAID SWITCH ENGAGEMENT WHEN THE DOOR HAS COMPLETED LOWERING MOVEMENT OR HAS ENGAGED AN OBSTRUCTION DURING LOWERING.