Automobile speed control

Claim 1

A SPEED CONTROL SYSTEM FOR AN AUTOMOBILE HAVING THROTTLE REGULATED PROPULSIVE MEANS AND BRAKES, COMPRISING MEANS PROVIDING A FIRST ELECTRICAL SIGNAL CORRESPONDING TO THE DESIRED AUTOMOBILE SPEED, MEANS PROVIDING A SECOND ELECTRICAL SIGNAL CORRESPONDING TO THE ACTUAL VEHICLE SPEED, MEANS PROVIDING A THIRD ELECTRICAL SIGNAL CORRESPONDING TO THE POSITION OF THE THROTTLE OF SAID PROPULSION MEANS, MEANS COMBINING SAID FIRST, SECOND AND THIRD SIGNALS TO PROVIDE AN ERROR SIGNAL A PRESSURE FLUID SOURCE, A PRESSURE FLUID ACTUATOR FOR POSITIONING SAID THROTTLE PROPORTIONATELY TO THE PRESSURE OF FLUID APPLIED THERETO, A PRESSURE CONTROL VALVE HAVING A SEALED CHAMBER, FIRST VALVE MEANS FOR CONTROLLING THE ADMISSION OF FLUID UNDER PRESSURE TO SAID CHAMBER AND SECOND VALVE MEANS FOR CONTROLLING THE EXHAUSTION OF FLUID FROM SAID CHAMBER, A CONDUIT CONNECTING THE CHAMBER OF SAID CONTROL VALVE TO SAID ACTUATOR, AND AMPLIFYING MEANS CONTROLLING SAID FIRST AND SECOND VALVE MEANS TO EITHER ADMIT FLUID UNDER PRESSURE TO SAID CONTROL VALVE CHAMBER OR TO EXHAUST FLUID FROM SAID CHAMBER DEPENDING UPON THE SENSE OF SAID ERROR SIGNAL AND IN PROPORTION TO THE MAGNITUDE OF SAID ERROR SIGNAL.