Vehicle suspension devices

Claim 1

A PNEUMATIC DEVICE FOR THE AUTOMATIC COMPENSATION FOR VARIATIONS IN LOAD IN AN ELASTIC SUSPENSION SUCH AS, FOR EXAMPLE, FOR USE IN A MOTOR VEHICLE IN MAINTAINING SUBSTANTIALLY CONSTANT THE MEAN HEIGHT OF THE BODY OR CHASSIS ABOVE THE GROUND, WHATEVER THE LOAD; SAID DEVICE COMPRISING A COLLAPSIBLE CASING CONNECTED AT ITS RESPECTIVE UPPER AND LOWER ENDS WITH THE RELATIVELY MOVABLE PARTS OF THE SUSPENSION, THE CASING COMPRISING A PAIR OF TELESCOPING INNER AND OUTER CYLINDRICAL MEMBERS HAVING RESPECTIVE OUTER AND INNER WALLS AXIALLY MOVABLE IN PROXIMITY TO EACH OTHER, SEALING MEANS BETWEEN THE INNER MEMBER TO PROVIDE WITHIN THE COLLAPSIBLE CASING A CHAMBER OF VARIABLE VOLUME CONTAINING COMPRESSIBLE PNEUMATIC FLUID SUBJECTED AT ALL TIMES TO THE LOAD ON THE SUSPENSION; A FLUID INLET PASSAGEWAY THROUGH THE WALL OF THE OUTER CYLINDRICAL MEMBER GIVING ACCESS FROM A SOURCE OF GASEOUS FLUID UNDER PRESSURE, AND A FLUID OUTLET PASSAGE FOR VENTING THE CHAMBER; MEANS WHEREBY THE RELATIVE POSITIONS OF THE TWO TELESCOPING CYLINDRICAL MEMBERS UNDER VARIABLE LOADING CONDITIONS CONTROL THE PASSAGE OF FLUID INTO AND OUT OF THE CHAMBER THROUGH THE RESPECTIVE PASSAGEWAYS, SAID MEANS OPERABLE UPON COMPRESSION OF THE PAIR OF CYLINDRICAL MEMBERS BEYOND A PREDETERMINED POINT TO ADMIT GASEOUS FLUID TO EXTEND THE CASING TOWARD A MEAN POSITION, SAID MEANS BEING OPERATIVE UPON EXTENSION OF SAID CASING BEYOND A PREDETERMINED POINT TO VENT GASEOUS FLUID TO PERMIT THE CYLINDRICAL MEMBERS TO CONTRACT TOWARD A MEAN POSITION; SAID LAST NAMED MEANS COMPRISING, WITH RESPECT TO SAID INLET PASSAGEWAY, AN ANNULAR VALVE SEAT SURROUNDING THE OPENING OF THE INLET PASSAGEWAY IN SAID OUTER WALL, A VALVE ELEMENT WITHIN THE OPENING AND MOVABLE TOWARD AND FROM SAID SEAT, A SPRING IN SAID PASSAGEWAY URGING SAID VALVE ELEMENT TOWARD SAID SEAT WITH A PORTION OF SAID ELEMENT PROJECTING INTO THE CHAMBER IN THE PATH OF A PART OF THE INNER MEMBER, WHEREBY SAID VALVE ELEMENT IS DISPLACED BACK INTO THE OPENING OF THE INLET PASSAGWAY AND OFF OF ITS SEAT AGAINST THE URGING OF THE SPRING TO ADMIT FLUID UNDER PRESSURE THROUGH SAID OPENING PAST SAID VALVE INTO SAID CHAMBER.