Spring suspension system for loadcarrying vehicles

Claim 1

IN A SPRING SUSPENSION SYSTEM, A TORSIONALLY DEFLECTABLE TUBULAR ELEMENT HAVING A LONGITUDINAL AXIS AND A GENERALLY CYLINDRICAL WALL SEPARATED BY A SINGLE SLOT PROVIDING SPACED UNCONNECTED WALL PORTIONS EXTENDING AXIALLY OF SAID TUBULAR ELEMENT FROM END TO END; FIRST MEANS CIRCUMFERENTIALLY CONTACTING THE ENDS OF THE TUBULAR ELEMENT FOR PRECLUDING RADIAL DISPLACEMENT OF THE SPACED UNCONNECTED PORTIONS OF THE GENERALLY CYLINDRICAL WALL AND ACCOMMODATING AXIAL DISPLACEMENT OF SAID WALL PORTIONS WHEN SAID TUBULAR ELEMENT IS TORSIONALLY DEFLECTED, SAID FIRST MEANS INCLUDING CYLINDRICAL SURFACES EXTENDING AXIALLY OF SAID TUBULAR ELEMENT IN SLIDABLE CONTACT WITH CYLINDRICAL SURFACES OF SAID GENERALLY CYLINDRICAL WALL IN THE END REGIONS OF SAID TUBULAR ELEMENT; AND SECOND MEANS INTERCONNECTING THE GENERALLY CYLINDRICAL WALL AND SAID FIRST MEANS IN FORCE-TRANSMITTING RELATIONSHIP FOR APPLYING FORCES TO SAID CYLINDRICAL WALL SUCH AS TO CAUSE TORSIONAL DEFLECTION OF SAID TUBULAR ELEMENT WITHOUT RESTRICTING AXIAL DISPLACEMENT OF THE SPACED UNCONNECTED WALL PORTIONS DURING SUCH TORSIONAL DEFLECTION; SAID GENERALLY CYLINDRICAL WALL AND SAID SLOT BEING RESPECTIVELY PROVIDED WITH SUBSTANTIALLY UNIFORM DIAMETERS AND WITH A WIDTH THROUGHOUT THE TUBULAR ELEMENT LENGTH SUCH THAT TORSIONAL DEFLECTION OF THE TUBULAR ELEMENT CAUSED BY SAID FIRST AND SECOND MEANS OCCURS THROUGHOUT THE LENGTH OF SAID TUBULAR ELEMENT WITHOUT CONTACT BETWEEN THE UNCONNECTED WALL PORTIONS.