Eccentric control-arm bushings and suspension systems using them

An eccentric control-arm bushing for an inboard portion of a control arm, the control-arm bushing comprising:

• a. an annular outer sleeve configured to be seated in an opening in the inboard portion;
• b. an inner sleeve assembly nonconcentrically surrounded by the outer sleeve and configured for being coupled to a frame of a vehicle platform;
• and
• c. an elastomeric material bonded to both the outer sleeve and the inner sleeve and molded to partly fill a gap therebetween, and at least partly deformable by a torque transmitted thereto by the outer sleeve,
• the nonconcentric surrounding being such that a maximum radial thickness of the partly filled gap is at least twice as thick as a minimum radial thickness thereof.

A vehicle platform comprising:

• first and second vehicle corner modules (VCMs) mounted on opposite sides of the vehicle platform, the first and second VCMs comprising respective suspension assemblies rotated 180° in a horizontal plane relative to each other,
• each of the first and second suspension assemblies including a control arm including two inboard portions, each of the two inboard portions including a respective opening and an eccentric bushing installed therein, each of the two respective bushings comprising:
• i. an annular outer sleeve seated in the respective opening,
• ii. an inner sleeve assembly nonconcentrically surrounded by the outer sleeve and non-pivotably coupled to a frame of the vehicle platform, and
• iii. an elastomeric material bonded to both the outer sleeve and the inner sleeve assembly, molded to partly fill a gap therebetween, and at least partly deformable to absorb a torque applied thereto by the outer sleeve, a maximum radial thickness of the partly filled gap being at least twice as thick as a minimum radial thickness thereof,
• wherein the two respective bushings are both oriented such that for each bushing, the maximum radial thickness of the partly filled gap is disposed outboardward of the inner sleeve assembly and the minimum radial thickness of the partly filled gap is disposed inboardward of the inner sleeve assembly.

A vehicle corner module (VCM) comprising a suspension system, the suspension system comprising a control arm and a plurality of control arm bushings installed in respective openings in a plurality of inboard portions of the control arm, wherein

• i. in a first orientation of the VCM, a first control arm bushing is a leading control arm bushing and a second control arm bushing is a trailing control arm bushing, and
• ii. in a second orientation of the VCM that is rotated 180° in a horizontal plane relative to the first orientation, the first control arm bushing is a trailing control arm bushing and the second control arm bushing is a leading control arm bushing, wherein:
• each of the first and second control arm bushings comprises (i) an annular outer sleeve seated in the opening of the respective inbound portion of the control arm, (ii) an inner sleeve assembly nonconcentrically surrounded by the outer sleeve and configured for fixed coupling to a frame of a vehicle platform, and (iii) an elastomeric material bonded to both the outer sleeve and the inner sleeve assembly, molded to partly fill a gap therebetween, and at least partly deformable to absorb a torque applied thereto by the outer sleeve, a maximum radial thickness of the partly filled gap being at least twice as thick as a minimum radial thickness thereof, wherein the two bushings are both oriented such that for each bushing, the maximum radial thickness of the partly filled gap is disposed outboardward of the inner sleeve assembly and the minimum radial thickness of the partly filled gap is disposed inboardward of the inner sleeve assembly.

A vehicle platform comprising:

• first and second vehicle corner modules (VCMs) mounted on opposite sides of the vehicle platform, and comprising respective suspension assemblies, each of the respective suspension assemblies comprising a control arm, the control arm including two inboard portions, each inboard portion including an eccentric bushing installed in an opening therein, each of the two bushings of the control arm being oriented such that for each bushing, a central longitudinal axis of the bushing is disposed inboardward of a parallel, central axis of the respective opening,
• wherein, when a respective at least partly vertical force is received by an outboard portion of the respective control arms of the suspension assemblies to pivot the control arms about the respective bushings,
• i. each of the control arms is constrained to pivot eccentrically about respective virtual pivot axes that are displaced inboardward from central axes of inner sleeve assemblies of the two respective bushings installed in the inboard-portion openings of each of the control arms, and
• ii. the eccentric pivoting of the control arms about the respective virtual pivot axes extends an effective length of each control arm, and is effective to constrain a negatively vertical displacement of a roll center of the vehicle platform.

A vehicle platform comprising:

• first and second vehicle corner modules (VCMs) mounted on opposite sides of the vehicle platform, and comprising respective suspension assemblies, each of the respective suspension assemblies comprising a control arm, the control arm including two inboard portions, each inboard portion including an eccentric bushing installed in an opening therein, each of the two bushings of the control arm being oriented such that for each bushing, a central longitudinal axis of the bushing is disposed inboardward of a parallel, central axis of the respective opening,
• wherein, when an at least partly vertical force is received by an outboard portion of the respective control arm of a single suspension assembly to pivot the control arm about the respective bushings,
• i. the control arm of the single suspension assembly is constrained to pivot eccentrically about respective virtual pivot axes that are displaced inboardward from the central axes of inner sleeve assemblies of the two bushings installed in the inboard-portion openings of the control arm, and
• ii. the eccentric pivoting of the control arm about the respective virtual pivot axes extends an effective length of the control arm, and is effective to constrain an outboardward displacement of a roll center of the vehicle platform.