US 12,083,849 B2
Torsion axle suspension system apparatus and method
Alex Potter, Grand Rapids, MN (US); William Allan Wake, Remer, MN (US); Cary Safe, Grand Rapids, MN (US); and Daniel K. Gilbert, Grand Rapids, MN (US)
Assigned to Yanmar Compact Equipment North America, Inc., Grand Rapids, MN (US)
Filed by Yanmar Compact Equipment North America, Inc., Grand Rapids, MN (US)
Filed on Nov. 18, 2022, as Appl. No. 18/057,115.
Prior Publication US 2024/0166014 A1, May 23, 2024
Int. Cl. B60G 21/05 (2006.01)
CPC B60G 21/052 (2013.01) [B60G 2200/21 (2013.01); B60G 2204/1434 (2013.01); B60G 2204/4302 (2013.01); B60G 2206/013 (2013.01); B60G 2206/20 (2013.01); B60G 2206/73 (2013.01); B60G 2300/04 (2013.01); B60G 2300/32 (2013.01)] 47 Claims
OG exemplary drawing
 
1. A torsion axle assembly used to support a vehicle body on an undercarriage, the torsion axle assembly comprising:
a) an elongated inner member having an inward end, an outward portion and an outer engaging surface, the elongated inner member having an inner member longitudinal axis extending through the inward end and the outward portion;
b) a torsion arm having an axle attachment point for interconnecting with the elongated inner member and an undercarriage attachment point for interconnecting with the undercarriage; the torsion arm having a torsion arm longitudinal axis extending from the axle attachment point to the undercarriage attachment point;
c) an elongated enclosure for interconnection to the vehicle body, the elongated enclosure having an inward portion and an open outward end, the elongated enclosure having an inner engaging surface at least partially defining an interior space, the interior space extending from the open outward end to the inward portion, the elongated enclosure further including an enclosure longitudinal axis extending through the inward portion and the open outward end; and wherein the open outward end is configured to receive the elongated inner member so that the elongated inner member resides at least partially within the interior space; and
d) resilient polymeric material residing within the interior space to engage and support the elongated inner member when the elongated inner member resides within the interior space, such that the inner member longitudinal axis resides at an unloaded camber angle to the enclosure longitudinal axis when none of the weight of the vehicle body is borne by the torsion axle assembly; and wherein the inner member longitudinal axis resides at a loaded camber angle to the enclosure longitudinal axis when the weight of the vehicle body is borne by the torsion axle assembly, such that the unloaded camber angle is greater than the loaded camber angle;
e) wherein the resilient polymeric material includes a plurality of torsion cords each having a larger cross-sectional area proximate one end of the respective torsion cord and a smaller cross-sectional area proximate the other end of the respective torsion cord, wherein the plurality of torsion cords include at least one upper torsion cord positioned generally upward from the inner member longitudinal axis of the respective elongated inner member, the upper torsion cord having the larger cross-sectional area located proximate the outward portion, and at least one lower torsion cord positioned generally downward from the inner member longitudinal axis of the respective elongated inner member, the lower torsion cord having the larger cross-sectional area located proximate the inward end.