Shifting device for the swiveling of cars

Claim 1

A SHIFTING DEVICE FOR SWIVELLING AN AUTOMOBILE HAVING A VEHICLE FRAME AND FRONT AND REAR WHEELS, COMPRISING A LIFTING DEVICE HAVING ITS UPPER END FIXED TO ONE END OF SAID VEHICLE FRAME BETWEEN THE CORRESPONDING WHEELS, A SWIVELLING DRIVE DEVICE HAVING A FRAME STRUCTURE FIXED TO THE LOWER END OF SAID LIFTING DEVICE, SAID SWIVELLING DRIVE DEVICE BEING NORMALLY HELD OFF THE GROUND AND LOWERED TO THE GROUND BY OPERATION OF SAID LIFTING DEVICE TO RAISE SAID CORRESPONDING WHEELS OFF THE GROUND, SAID SWIVELLING DRIVE DEVICE INCLUDING AT LEAST TWO CONVEYOR ROLLS OF SUBSTANTIAL LENGTH DISPOSED IN AND PROJECTING BENEATH SAID FRAME STRUCTURE, EACH OF SAID CONVEYOR ROLLS BEING SUPPORTED ON AXLES AND BEARINGS AT ITS ENDS, AND HAVING ITS AXIS IN A SUBSTANTIALLY HORIZONTAL PLANE, A COIL SPRING FOR EACH END BEARING HAVING ITS LOWER END ABUTTING SAID END BEARING AND ITS UPPER END ABUTTING SAID FRAME STRUCTURE, WHEREBY SAID ROLLS WILL MAINTAIN A SUFFICIENTLY EXTENDED SURFACE CONTACT WITH THE GROUND TO PROVIDE GOOD TRACTION ON SOFT AND VARIABLY INCLINED ROAD SURFACES, AND REVERSIBLE POWER MEANS MOUNTED IN SAID FRAME STRUCTURE AND A FLEXIBLE BELT DRIVE MEANS DRIVABLY CONNECTING SAID CONVEYOR ROLLS AND SAID POWER MEANS TO DRIVE SAID ROLLS AT WILL IN EITHER DIRECTION.