Tractor trailer dumping hopper vehicle

Claim 1

A DUMP TRUCK COMPRISING AN ELONGATED SUBSTANTIALLY RECTANGULAR FRAME STRUCTURE; A HOPPER-SHAPED LOAD COMPARTMENT FOR BULK MATERIAL SUPPORTED ON THE FRAME INTERMEDIATE THE ENDS OF THE LATTER AND HAVING A DOOR-CONTROLLED BOTTOM DISCHARGE OPENING DISPOSED APPROXIMATELY SYMMETRICALLY IN RELATION TO A VERTICAL PLANE THROUGH THE LONGITUDINAL CENTER LINE OF THE TRUCK; AND DUAL-AXLE RUNNING GEAR SUPPORTING THE REAR END OF THE TRUCK FRAME, SAID RUNNING GEAR COMPRISING A RIGID HIGH-ARCHED SADDLE STRUCTURE HAVING A HORIZONTAL YOKE AND A PAIR OF MUTUALLYSPACED DEPENDENT LEGS AND BEING SECURED TO THE UNDER SIDE OF THE TRUCK FRAME WITH ITS YOKE DISPOSED TRANSVERSELY OF THE FRAME, A PAIR OF MUTUALLY PARALLEL WALKING BEAMS DISPOSED LONGITUDINALLY OF THE TRUCK FRAME AND HAVING THEIR RESPECTIVE MIDSECTIONS PIVOTALLY CONNECTED TO THE LOWER ENDS OF THE TWO SADDLE LEGS, A PAIR OF RIGID HIGH-ARCHED AXLE STRUCTURES DISPOSED PARALLEL TO THE TRANSVERSE SADDLE WITH ONE IN FRONT OF AND THE OTHER TO THE REAR OF THE SADDLE AND EACH HAVING AN UPSTANDING ARCH COMPRISING A YOKE AND TWO DEPENDING LEGS AND ALSO HAVING TWO WHEEL BEARING PARTS CONNECTED, RESPECTIVELY, TO LOWER ENDS OF THE LEG PARTS OF THE ARCH, MEANS PIVOTALLY CONNECTING THE LOWER LEG PARTS OF THE FRONT AXLE TO THE FRONT ENDS OF THE WALKING BEAMS AND MEANS SIMILARLY CONNECTING THE REAR AXLE TO THE REAR ENDS OF THE WALKING BEAMS, MEANS FOR NORMALLY HOLDING THE ARCHED PORTION OF EACH AXLE IN AN UPRIGHT POSITION WITH ITS YOKE PART APPROXIMATELY AT THE SAME HEIGHT AS THE YOKE OF THE SADDLE, AND FOUR GROUND-ENGAGING WHEEL UNITS MOUNTED, RESPECTIVELY, ON THE FOUR BEARING PARTS OF THE TWO AXLES.