Vehicle speed control mechanism

Claim 1

A VEHICLE SPEED WARNING AND SPEED MAINTAINING SYSTEM IN A VEHICLE HAVING AN ENGINE AND AN ENGINE THROTTLE AND THROTTLE CONTROL LINKAGE INCLUDING AN ACCELERATOR PEDAL AND A THROTTLE CLOSING SPRING, SAID SYSTEM COMPRISING: MEANS SENSING VEHICLE SPEED AND A REFERENCE SPEED AND GENERATING A VEHICLE SPEED ERROR SIGNAL; A MASTER VALVE MOVING IN ACCORDANCE WITH SAID SPEED ERROR SIGNAL; A FIRST SOURCE OF ATMOSPHERIC PRESSURE AND A SECOND SOURCE OF PRESSURE DIFFERENT FROM ATMOSPHERIC PRESSURE; SLAVE VALVE MEANS INCLUDING A SLAVE VALVE AND A VALVE BODY RECEIVING SAID SLAVE VALVE AND HAVING PRESSURE INLET MEANS AND FIRST AND SECOND PRESSURE OUTLET MEANS CONTROLLED BY SAID SLAVE VALVE, SAID PRESSURE INLET MEANS RECEIVING PRESSURES FROM SAID PRESSURE SOURCES, AND POWER MEANS CONNECTED TO MOVE SAID SLAVE VALVE IN SAID VALVE BODY AND CONTROLLED BY SAID MASTER VALVE; SAID SLAVE VALVE MEANS GENERATING A FIRST MODULATED PRESSURE FROM SAID PRESSURE SOURCE PRESSURES IN SAID FIRST PRESSURE OUTLET MEANS AT A PREDETERMINED VEHICLE SPEED ERROR SIGNAL INDICATING A VEHICLE SPEED SUBSTANTIALLY EQUAL TO REFERENCE SPEED, AND CONNECTING ONLY THE PRESSURE FROM THE SECOND PRESSURE SOURCE TO SAID FIRST PRESSURE OUTLET MEANS AT A SECOND VEHICLE SPEED ERROR SIGNAL INDICATING A VEHICLE SPEED GREATER THAN THE REFERNECE SPEED, AND GENERATING A SECOND MODULATED PRESSURE FROM SAID PRESSURE SOURCE PRESSURES IN SAID SECOND PRESSURE OUTLET MEANS AT THE FIRST PREDETERMINED VEHICLE SPEED ERROR SIGNAL, SAID MODULATED PRESSURES VARYING IN ACCORDANCE WITH VARIATIONS IN THE VEHICLE SPEED ERROR SIGNAL; A FIRST PRESSURE ACTUATED SERVOMOTOR CONNECTED WITH SAID LINKAGE TO EXERT A FORCE THEREON WHEN ACTUATED URGING SAID LINKAGE TOWARD A THROTTLE CLOSING POSITION; A SECOND PRESSURE ACTUATED SERVOMOTOR CONNECTED WITH SAID LINKAGE TO EXERT A FORCE THEREON WHEN ACTUATED URGING SAID LINKAGE TOWARD A THROTTLE OPENING POSITION; AND MEANS SELECTIVELY CONNECTING SAID FIRST PRESSURE OUTLET MEANS IN PRESSURE COMMUNICATION WITH SAID FIRST SERVOMOTOR AND CLOSING SAID SECOND PRESSURE OUTLET MEANS AND CONNECTING SAID SECOND SERVOMOTOR IN PRESSURE COMMUNICATION WITH SAID FIRST PRESSURE SOURCE TO DEACTUATE SAID SECOND SERVOMOTOR AND ESTABLISH A SPEED WARNING MODE OF SYSTEM OPERATION, AND SELECTIVELY CONNECTING SAID SECOND PRESSURE OUTLET MEANS IN PRESSURE COMMUNICATION WITH SAID SECOND SERVOMOTOR AND CLOSING SAID FIRST PRESSURE OUTLET MEANS AND CONNECTING SAID FIRST SERVOMOTOR IN PRESSURE COMMUNICATION WITH SAID FIRST PRESSURE SOURCE TO DEACTUATE SAID FIRST SERVOMOTOR AND ESTABLISH A SPEED MAINTAINING MODE OF SYSTEM OPERATION.