Convertible tandem suspension system for a semitrailer

Claim 1

IN COMBINATION: A TRAILER FRAME; A PAIR OF ADJACENT SUSPENSION AXLE ASSEMBLIES UNDER THE REAR OF SAID FRAME, ONE BEHIND THE OTHER; THE FOREMOST OF SAID ASSEMBLIES HAVING MOUNTING MEANS TO SAID FRAME TO SECURE IT; THE REARMOST OF SAID ASSEMBLIES HAVING INDEPENDENT MOUNTING MEANS INCLUDING FORWARD EXTENDING ATTACHMENT MEANS; BRACKET MEANS SUSPENDED BENEATH SAID FRAME AND RECEIVING SAID ATTACHMENT MEANS; SAID BRACKET MEANS INCLUDING GUIDE MEANS ENGAGEABLE WITH SAID ATTACHMENT MEANS TO ALLOW MOVEMENT OF SAID ATTACHMENT MEANS WITH RESPECT TO SAID BRACKET MEANS, INDEPENDENTLY OF SAID FOREMOST ASSEMBLY, FORE AND AFT OF SAID FRAME FROM A FORWARD POSITION ADJACENT SAID FOREMOST ASSEMBLY TO A REARWARD POSITION SPACED SUBSTANTIALLY FROM SAID REARMOST ASSEMBLY; SHIFTABLE LOCKING MEANS ENGAGEABLE BETWEEN PORTIONS OF SAID BRACKET MEANS AND SAID ATTACHMENT MEANS IN SHIFTED POSITIONS OF THE LATTER; A FIFTH WHEEL CONNECTOR MOUNTED ON SAID REARMOST ASSEMBLY GENERALLY ABOVE THE AXLE THEREOF, AND SHIFTABLE THEREWITH; SAID CONNECTOR AND AXLE BEING SHIFTABLE FROM A FORWARD POSITION BENEATH SAID FRAME TO A REARWARD POSITION EXTENDED BEHIND SAID FRAME IN AN UNOBSTRUCTED ARRANGEMENT; SAID FIFTH WHEEL CONNECTOR NORMALLY HAVING SUFFICIENTLY SMALL CLEARANCE FROM SAID FRAME IN SAID FORWARD POSITION TO ALLOW FREE MOVEMENT THEREOF WHEN SAID FRAME IS NOT LOADED AND TO PROVIDE SUPPLEMENTAL SUPPORT TO A LOAD ON SAID FRAME, AND HAVING SUFFICIENT EXTENSION BEHIND SAID FRAME IN SAID REARMOST POSITION TO RECEIVE A TANDEM TRAILER ATTACHMENT.