Control for a power drive system and including shift-restricting inhibitors for a reversible transmission

Claim 1

IN A SYSTEM FOR DRIVING A LOAD FROM A PRIME MOVER, THE COMBINATION COMPRISING A TRANSMISSION HAVING INPUT AND OUTPUT SHAFTS COUPLED RESPECTIVELY TO THE PRIME MOVER AND THE LOAD, SAID TRANSMISSION HAVING DRIVE MESNS ENGAGEABLE TO PRODUCE DRIVE OF SAID OUTPUT SHAFT IN A GIVEN DIRECTION, AN ACTUATOR AND MEANS RESPONSIVE TO ACTIVATION THEREOF TO ENGAGE SAID DRIVE MEANS, AN ACTIVATING FLUID SYSTEM CONNECTED TO SELECTIVELY ACTIVATE SAID ACTUATOR AND THEREBY SET SAID TRANSMISSION TO DRIVE THE LOAD IN A GIVEN DIRECTION, MEANS FOR SENSING AND SIGNALING WHEN THE LOAD IS BEING DRIVEN IN THE DIRECTION OPPOSITE TO SAID GIVEN DIRECTION, INHIBIT MEANS RESPONSIVE TO SIGNALING FROM SAID SENSING MEANS TO PREVENT ACTIVATION OF SAID ACTUATON MEANS TO DISABLE SAID INHIBIT MEANS WHEN SAID DRIVE MEANS IS ENGAGED PRIOR TO SIGNALING BY SAID SENSING MEANS, A BRAKE SYSTEM INCLUDING MEANS OPERABLE IN RESPONSE TO RECEIVING PRESSURE FLUID TO RETARD ROTATION OF SAID OUTPUT SHAFT, A SOURCE OF PRESURE FLUID INCLUDING MEANS TO SELECTIVELY CONDUCT PRESSURE FLUID TO SAID RETARDING MEANS TO SLOW SAID OUTPUT SHAFT, MEANS FOR SENSING THE PRESSURE OF THE FLUID OF SAID SOURCE AND GENERATING A SECOND SIGNAL IN RESPONSE TO SAID PRESSURE BEING BELOW A PREDETERMINED VALUE, AND MEANS ACTING IN RESPONSE TO SAID SECOND SIGNAL FOR DISABLING SAID INHIBIT MEANS AND THEREBY ALLOW SAID TRANSMISSION TO BE SET TO DRIVE THE OUTPUT SHAFT IN SAID GIVEN DIRECTION TO RETARD OF SAID OUTPUT SHAFT AND STOP THE LOAD.