Variable speed transmission

Claim 1

A VARIABLE SPEED TRANSMISSION COMPRISING A DRIVEN MEMBER; A DRIVING MEANS INCLUDING A CONSTANT SPEED DRIVE AND A VARIABLE SPEED DRIVE HAVING A HYDRAULIC PUMP HAVING A VARIABLE VOLUMETERIC OUTPUT AND A HYDRAULIC MOTOR HAVING A CONSTANT VOLUMETRIC DISPLACEMENT, THE PUMP BEING DRIVEN BY SAID CONSTANT SPEED DRIVE AND SAID VARIABLE SPEED DRIVE HAVING A RANGE OF SPEED CHANGE FROM A DETERMINATE VALUE IN ONE DIRECTION TO NIL AND A SECOND RANGE OF SPEED CHANGE FROM NIL TO SAID DETERMINATE VALUE IN THE OPPOSITE DIRECTION, SAID DETERMINATE VALUE BEING SUBSTANTIALLY THE SAME AS THE VALUE OF THE CONSTANT SPEED DRIVE; MEANS FOR ADJUSTING THE VARIABLE SPEED DRIVE SOLELY BY VARYING THE VOLUMETRIC OUTPUT OF THE PUMP FOR VARYING THE OUTPUT SPEED AND DIRECTION OF THE VARIABLE SPEED DRIVE BETWEEN SAID FIRST AND SECOND DETERMINATE VALUES; AND MEANS FOR CONNECTING BOTH THE CONSTANT SPEED DRIVE AND VARIABLE SPEED DRIVE TO SAID DRIVEN MEMBER, AND DRIVING MEANS TRANSMITTING NO MOTION TO SAID DRIVEN MEMBER WHEN SAID VARIABLE SPEED DRIVE IS OPERATING AT SAID FIRST DETERMINATE VALUE AND TRANSMITTING INCREASING MOTION TO DRIVE THE DRIVEN MEMBER SOLELY IN SAID ONE DRIECTION AS SAID VARIABLE SPEED DRIVE IS VARIED THROUGH SAID FIRST RANGE TO NIL AND THEREAFTER THROUGH SAID SECOND RANGE IN THE OPPOSITE DIRECTION TO SAID DETERMINATE VALUE.