Fluid suspension

Claim 1

A FLUID SUSPENSION SYSTEM FOR MOTOR VEHICLES HAVING A CHASSIS AND A PLURALITY OF WHEELS, COMPRISING A CYLINDER ADAPTED FOR CONNECTION WITH SAID CHASSIS; A PISTON SLIDABLY MOUNTED IN SAID CYLINDER, SAID PISTON CARRYING AT ONE END A PISTON ROD THAT EXTENDS THROUGH SAID CYLINDER FOR CONNECTION WITH A WHEEL, SAID PISTON DEFINING A FIRST AND SECOND CHAMBERS AT OPPOSITE ENDS OF SAID CYLINDER, SAID PISTON CONTAINING A THROUGH PASSAGE FOR AFFORDING COMMUNICATION BETWEEN SAID CHAMBERS; MAIN SUPPLY MEANS FOR SUPPLYING PRESSURE FLUID DIRECTLY TO SAID CHAMBER, SAID MAIN SUPPLY DUCT MEANS INCLUDING PRESSURE-ADJUSTING VALVE MEANS FOR VARYING THE FLEXIBILITY OF THE SUSPENSION SYSTEM; SECONDARY SUPPLY DUCT MEANS FOR SUPPLYING PRESSURE FLUID TO SAID SECOND CHAMBER, SAID SECONDARY DUCT MEANS INCLUDING A FIRST NORMALLY-CLOSED ONE-WAY VALVE; A RETURN DUCT CONNECTED WITH SAID FIRST CHAMBER AND INCLUDING A SECOND NORMALLY-CLOSED ONE-WAY VALVE; A THIRD NORMALLY-CLOSED ONE-WAY VALVE IN SAID PISTON PASSAGE; FIRST AND SECOND FINGER MEANS CARRIED BY SAID PISTON AND SAID ROD, RESPECTIVELY, FOR OPENING SAID FIRST AND SECOND ONE-WAY VALVES ONLY WHEN SAID PISTON IS DISPLACED IN A DIRECTION REDUCING THE VOLUME OF SAID SECOND CHAMBER BEYOND A PREDETERMINED LIMIT; AND THIRD FINGER MEANS CARRIED BY SAID CYLINDER FOR OPENING SAID THIRD ONE-WAY VALVE ONLY WHEN THE PISTON IS DISPLACED IN THE OPPOSITE DIRECTION TO REDUCE THE VOLUME OF SAID FIRST CHAMBER BEYOND A PREDETERMINED LIMIT.