# US 9,039,034 B2 · Multiple axle equalizing rubber suspension > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,039,034 B2 - Document ID: US9039034B2 - Status: Granted - Kind: B2 - Application number: 13/913,582 - Filed: 2013-06-10 - Published: 2014-08-14 - Granted: 2015-05-26 - Earliest claimed: 2013-02-13 - Assignees: Transportation Technologies, Inc. - Applicants: Transportation Technologies, Inc. - Inventors: Ervin K. VanDenberg; David H. Croston; Michael K. Powers - Web page: https://patentgrep.com/patent/US9039034B2 ## CPC - B60G 5/04: with two or more pivoted arms, the movements of which are resiliently interrelated {, e.g. the arms being rigid} - B60G 11/18: having torsion-bar springs only {(B60G11/006 takes precedence; having rubber springs of the torsional-energy-absorption type B60G11/23)} - B60G 11/225: {Neidhart type rubber springs} - B60G 2300/04: Trailers - B60G: VEHICLE SUSPENSION ARRANGEMENTS (air-cushion vehicles B60V; {cycle suspensions B62K25/00}) ## Abstract A suspension system for a vehicle includes a frame mounting bracket for mounting to the vehicle. The suspension includes front and rear rubber torsion axle assemblies. Front and rear lever assemblies are respectively pivotally attached to the vehicle at front and rear lever pivot points. Outer housings of the rubber torsion axle assemblies are each respectively rigidly mounted to the front and rear lever assemblies. A rigid control arm is pivotally connected at one end to the front lever assembly at a front control arm pivot point and its other end is pivotally connected to the rear lever assembly at a rear control arm pivot point. When the suspension assembly encounters a force causing the front lever assembly to rotate in one direction about the front lever pivot point the rigid control arm causes the rear lever assembly to rotate about the rear lever pivot in an opposite direction. ## Claims ### Claim 1 A suspension assembly for a vehicle comprising: a front rubber torsion axle assembly with an outer housing; a front spindle swing arm; wherein the front rubber torsion axle assembly further comprises: a front central torsion axle shaft; front rubber springs, wherein the front rubber springs are located between the outer housing of the front rubber torsion axle assembly and the front central torsion axle shaft; wherein the front spindle swing arm is rotatable with the front central torsion axle shaft about a forward spindle pivot; a rear rubber torsion axle assembly with an outer housing; a rear spindle swing arm; wherein the rear rubber torsion axle assembly further comprises: a rear central torsion axle shaft; rear rubber springs, wherein the rear rubber springs are located between the outer housing of the rear rubber torsion axle assembly and the rear central torsion axle shaft; wherein the rear spindle swing arm is rotatably connected to the rear central torsion axle shaft to rotate about a rear spindle pivot; a front lever adapted to be pivotally attached to the vehicle at a front lever pivot point, wherein the outer housing of the front rubber torsion axle assembly is rigidly mounted to the front lever; a rear lever adapted to be pivotally attached to the vehicle at a rear lever pivot point, wherein the outer housing of the rear rubber torsion axle assembly is rigidly mounted to the rear lever, wherein with respect to a normal forward traveling direction of the vehicle, the front lever is mounted forward of the rear lever; a rigid control arm pivotally connected to the front lever at a front control arm pivot point and pivotally connected to the rear lever at a rear control arm pivot point, wherein the suspension assembly is configured so that when the suspension assembly encounters a force causing the front lever to rotate in a front rotational direction about the front lever pivot point, the rigid control arm is configured to cause the rear lever to rotate about the rear lever pivot point in a rear rotational direction that is opposite the front rotational direction; and wherein with respect to the normal forward traveling direction of the vehicle, the front lever pivot point is forward of the front control arm pivot point and the forward spindle pivot, and wherein the rear lever pivot point is forward of the rear control arm pivot point and the rear spindle pivot. ### Claim 2 (depends on 1) The suspension assembly of claim 1 wherein when the suspension assembly is in a static no-load condition, the front control arm pivot point is higher than the front lever pivot point and the rear lever pivot point is higher than the rear control arm pivot point. ### Claim 3 (depends on 1) The suspension assembly of claim 1 wherein the forward spindle pivot is lower than the front control arm pivot point. ### Claim 4 (depends on 1) The suspension assembly of claim 1 wherein with respect to the normal forward traveling direction of the vehicle, the front lever extends rearward from the front lever pivot point and the rear lever extends rearward from the rear lever pivot point. ### Claim 5 (depends on 1) The suspension assembly of claim 1 further comprising: a front wheel assembly mounted to the front spindle swing arm; a rear wheel assembly mounted to the rear spindle swing arm, wherein when the front wheel assembly moves downward, the rear wheel assembly moves upward. ### Claim 6 (depends on 5) The suspension assembly of claim 5, wherein when the front wheel assembly encounters a force, the front rubber torsion axle assembly reacts to absorb at least some of the force and the rear rubber torsion axle assembly acts in series with the front rubber torsion axle assembly to absorb at least some of the force. ### Claim 7 (depends on 1) The suspension assembly of claim 1 wherein a spring rate of the front rubber torsion axle assembly when cooperating with the rear rubber torsion axle assembly is about half the spring rate of the front rubber torsion axle assembly which would be exhibited without the rear rubber torsion axle assembly cooperating with the front rubber torsion axle assembly. ### Claim 8 A suspension assembly for a vehicle comprising: a front rubber torsion axle assembly with an outer housing; a rear rubber torsion axle assembly with an outer housing; a front lever adapted to be pivotally attached to the vehicle at a front lever pivot point, wherein the outer housing of the front rubber torsion axle assembly is rigidly mounted to the front lever; a rear lever adapted to be pivotally attached to the vehicle at a rear lever pivot point, wherein the outer housing of the rear rubber torsion axle assembly is rigidly mounted to the rear lever, wherein with respect to a normal forward traveling direction of the vehicle, the front lever is mounted forward of the rear lever; a rigid control arm pivotally connected to the front lever at a front control arm pivot point and pivotally connected to the rear lever at a rear control arm pivot point, wherein the suspension assembly is configured so that when the suspension assembly encounters a force causing the front lever to rotate in a front rotational direction about the front lever pivot point, the rigid control arm is configured to cause the rear lever to rotate about the rear lever pivot point in a rear rotational direction that is opposite the front rotational direction; and wherein with respect to the normal forward traveling direction of the vehicle, the front lever extends rearward from the front lever pivot point and the rear lever extends rearward from the rear lever pivot point. ### Claim 9 (depends on 8) The suspension assembly of claim 8 further comprising: a front spindle swing arm, and wherein the front rubber torsion axle assembly further comprises: a front central torsion axle shaft; front rubber springs, wherein the front rubber springs are located between the outer housing of the front rubber torsion axle assembly and the front central torsion axle shaft; and wherein the front spindle swing arm is rotatable with the front central torsion axle shaft about a forward spindle pivot. ### Claim 10 (depends on 9) The suspension assembly of claim 9 wherein the forward spindle pivot is lower than the front control arm pivot point. ### Claim 11 (depends on 9) The suspension assembly of claim 9 further comprising: a rear spindle swing arm, and wherein the rear rubber torsion axle assembly further comprises: a rear central torsion axle shaft; rear rubber springs, wherein the rear rubber springs are located between the outer housing of the rear rubber torsion axle assembly and the rear central torsion axle shaft; and wherein the rear spindle swing arm is rotatably connected to the rear central torsion axle shaft to rotate about a rear spindle pivot. ### Claim 12 (depends on 11) The suspension assembly of claim 11 wherein with respect to the normal forward traveling direction of the vehicle, the front lever pivot point is forward of the front control arm pivot point and the forward spindle pivot, and wherein the rear lever pivot point is forward of the rear control arm pivot point and the rear spindle pivot. ### Claim 13 (depends on 8) The suspension assembly of claim 8 wherein when the suspension assembly is in a static no-load condition, the front control arm pivot point is higher than the front lever pivot point and the rear lever pivot point is higher than the rear control arm pivot point. ### Claim 14 (depends on 8) The suspension assembly of claim 8 further comprising: a front spindle swing arm mounted to the front rubber torsion axle assembly; a front wheel assembly mounted to the front spindle swing arm; a rear spindle swing arm mounted to the rear rubber torsion axle assembly; a rear wheel assembly mounted to the rear spindle swing arm, wherein when the front wheel assembly moves downward, the rear wheel assembly moves upward. ### Claim 15 (depends on 14) The suspension assembly of claim 14, wherein when the front wheel assembly encounters a force, the front rubber torsion axle assembly reacts to absorb at least some of the force and the rear rubber torsion axle assembly acts in series with the front rubber torsion axle assembly to absorb at least some of the force. ### Claim 16 (depends on 8) The suspension assembly of claim 8 wherein a spring rate of the front rubber torsion axle assembly when cooperating with the rear rubber torsion axle assembly is about half the spring rate of the front rubber torsion axle assembly which would be exhibited without the rear rubber torsion axle assembly cooperating with the front rubber torsion axle assembly.