SHEAR CENTER RAISING TWIST AXLE WITH INTERNAL AND TUNABLE TRANSITIONING GUSSETS
A trailing rear suspension for a motor vehicle having a twist beam axle coupled at its ends to a pair of trailing arms wherein the twist beam axle raises the shear center of the central portion of its cross-beam above the wheel center of the vehicle. The raising of the shear center is achieved by rotating the cross-beam to orient one leg of its cross-section to be aligned with the top of the trailing arms.
1 . A vehicle trailing rear suspension assembly comprising
first and second trailing arms, and
a cross-beam coupled to and extending between the first and second trailing arms, the cross-beam having a open cross section of uniform shape extending the length of the cross-beam and a rear facing opening, wherein the shear center of the cross-beam is positioned adjacent the top of the open cross section of the cross-beam.
2 . The assembly of claim 1 further comprising first and second gussets internally coupled on a first end to the cross-beam and coupled on a second end to the first and second the trailing arms.
3 . The assembly of claim 1 wherein the open cross section of the cross-beam being U shape and having first and second legs.
4 . The assembly of claim 3 wherein in a first leg of the U shaped cross section is aligned with a top of the first and second trailing arms.
5 . The assembly of claim 2 wherein the first end of the first and second gussets having a U shape cross section.
6 . The assembly of claim 1 wherein the cross-beam includes a torsional stiffness that is a function of an active length of the cross-beam.
7 . The assembly of claim 6 wherein the active length of the twist beam is a function of the length of first and second gussets internally coupled on a first end to the cross-beam and coupled on a second end to the first and second the trailing arms.
8 . A motor vehicle having a trailing rear suspension assembly, the trailing rear suspension assembly comprising
a twist beam axle having a cross-beam having a open cross section of uniform shape and a rear facing opening extending the length of the cross-beam between first and second ends, and
first and second trailing arms coupled to the first and second ends of the cross-beam, wherein the shear center of the cross-beam is positioned adjacent the top of the open cross section of the cross-beam.
9 . The vehicle of claim 8 further comprising first and second gussets internally coupled on a first end to the cross-beam and coupled on a second end to the first and second the trailing arms,
10 . The vehicle of claim 8 wherein the open cross section of the cross-beam being U shape and having first and second legs.
11 . The vehicle of claim 10 wherein in a first leg of the U shaped cross section is aligned with a top of the first and second trailing arms.
12 . The vehicle of claim 9 wherein the first end of the first and second gussets having a U shape cross section.
13 . The vehicle of claim 8 wherein the cross-beam includes a torsional stiffness that is a function of an active length of the cross-beam.
14 . The vehicle of claim 13 wherein the active length of the twist beam is a function of the length of the first and second gussets .