Power lift mechanism for mowers and the like

Claim 1

IN A MOWER OR THE LIKE OF THE TYPE HAVING WHEELED FRAME MEANS, MOWING MEANS INCLUDING A CUTTER BAR PIVOTALLY MOUNTED ON SAID FRAME MEANS FOR SWINGING MOVEMENT BETWEEN A LOWERED MOWING POSITION AND A LIFTED TRANSPORT POSITION, AND MOWER DRIVE MEANS MOUNTED ON SAID FRAME MEANS AND DRIVINGLY CONNECTED TO SAID MOWING MEANS; THE IMPROVEMENT COMPRISING AN EXTENSIBLE AND RETRACTABLE SCREW JACK INCLUDING A PAIR OF RELATIVELY RECIPROCABLE MEMBERS RESPECTIVELY OPERATIVELY CONNECTED TO SAID FRAME MEANS AND SAID CUTTER BAR TO CONTROL MOVEMENT OF THE LATTER BETWEEN SAID POSITIONS, CLUTCH MEANS, DRIVE MEANS CONNECTING SAID CLUTCH MEANS TO SAID SCREW JACK TO CONTROL ACTUATION OF THE LATTER, BRAKE MEANS MOUNTED ON SAID FRAME MEANS, MANUALLY OPERABLE MEANS MOUNTING SAID CLUTCH MEANS ON SAID FRAME FOR MOVEMENT BETWEEN A FIRST POSITION IN WHICH SAID CLUTCH MEANS ENGAGES SAID MOWER DRIVE MEANS TO POWER ACTUATE SAID SCREW JACK, A SECOND POSITION IN WHICH SAID CLUTCH MEANS ENGAGES AND IS BRAKED BY SAID BRAKE MEANS TO HOLD SAID SCREW JACK SUBSTANTIALLY STATIONARY, AND A THIRD POSITION IN WHICH SAID CLUTCH MEANS MAY FREE-WHEEL OUT OF ENGAGEMENT WITH SAID MOWER DRIVE MEANS AND SAID BRAKE MEANS, AND MEANS OPERATIVELY ASSOCIATED WITH SAID CLUTCH MEANS FOR SELECTIVELY HOLDING THE LATTER IN SAID THIRD POSITION THEREOF UPON RELEASE OF SAID MANUALLY OPERABLE MEANS.