Hoist comprising automatic variable speed winding means

Claim 1

HOISTING APPARATUS COMPRISING AN ELECTRIC MOTOR CONNECTABLE TO OPERATE AS EITHER A TWO-POLE OR A FOURPOLE MOTOR AND TO DEVELOP A DISTINCTLY GREATER TORQUE WHEN CONNECTED FOR OPERATION AS A FOUR-POLE MOTOR THAN AS A TWO-POLE MOTOR, A CONTROL SWITCH MOVABLE BETWEEN A FIRST POSITION IN WHICH CONNECTS SAID MOTOR TO DEVELOP ONE OF SAID TORQUES AND A SECOND POSITION IN WHICH IT CONNECTS SAID MOTOR TO DEVELOP THE OTHER OF SAID TORQUES MEANS BIASING SAID SWITCH TOWARD SAID SECOND POSITION ACTUATING MEANS MOVABLE BETWEEN A FIRST POSITION IN WHICH IT HOLDS SAID SWITCH IN ITS FIRST POSITION AND A SECOND POSITION IN WHICH IT PERMITS SAID SWITCH TO ASSUME ITS SECOND POSITION, MEANS BIASING SAID ACTUATING MEANS TOWARD ITS SECOND POSITION, FLEXIBLE LOAD SUPPORTING MEANS CONNECTED AT ONE END TO SAID ACTUATING MEANS TO TRANSFER THERETO BY SAID LOAD SUPPORTING MEANS, AND MOVE SAID SUPPORTED BY SAID LOAD SUPPORTING MEANS, AND MOVE SAID ACTUATING MEANS AND SWITCH MEANS INTO THEIR FIRST POSITIONS WHEN SAID PREDETERMINED LOAD PORTION IS SUFFICIENT TO OVERCOME THE FORCE EXERTED BY SAID BIASING MEANS, AND MEANS DRIVEN BY SAID MOTOR CONNECTED TO WIND UP AND UNWIND SAID FLEXIBLE LOAD SUPPORTING MEANS.