Suspension system for vehicle frame

In combination with a frame for a vehicle, said frame including:

• a front structure spaced above the ground and including an inner portion and an outer portion,
• at least one ground engaging wheel mounted on said outer portion of said front structure,
• a rear structure spaced above the ground and including an inner portion and an outer portion, and
• at least two ground engaging wheels mounted on said outer portion of said rear structure,
• the improvements comprising suspension means to compensate for frame flexure when the vehicle accelerates, said suspension means including
• (a) means for connecting said inner portions of said front structure and said rear structure at a primary pivot point (62) such that said front and rear structures can turn about said pivot point, said primary pivot point being at a selected elevation above the ground when said vehicle frame is stationary;
• (b) linkage means for pivotally interconnecting a first pivot point (37) on said inner portion of said rear structure with a second pivot point (26) on said inner portion of said front structure, said linkage means including at least one link interconnecting said first and second pivot points, said linkage means permitting the distance between said first and second pivot points to alter when said inner portions of said front and rear structures are upwardly displaced away from the ground and pivot about said primary pivot point;
• and,
• (c) resilient shock absorber means (42) mounted on said vehicle frame to dampen the movement of said inner portions of said front and rear structures when the vehicle accelerates and said front and rear structures are displaced upwardly away from the ground and pivot about said primary pivot point;
• said resilient shock absorber means including
• (i) a first end pivotally connected to said linkage means at a third pivot point (41) separate from said primary, first, and second pivot points, and
• (ii) a second end pivotally connected to said frame at a fourth pivot point (67), said third pivot point being a selected distance from said fourth pivot point when the vehicle is stationary,
• said linkage means, when the vehicle accelerates and said inner portions of said front and rear structures are upwardly displaced away from the ground,
• (iii) pivoting about said first and second pivot points, and,
• (iv) altering the distance between said third and fourth pivot points, said resilient shock absorber means pivoting about said third and fourth pivot points and dampening the movement of said linkage means when the distance between said third and fourth pivot points is altered.

In combination with a frame for a vehicle, said frame including

• a front structure spaced above the ground and including an inner portion and an outer portion,
• at least one ground engaging wheel mounted on said outer portion of said front structure,
• a rear structure spaced above the ground and including an inner portion and an outer portion, and
• at least two ground engaging wheels mounted on said outer portion of said rear structure,
• the improvements comprising suspension means to compensate for frame flexure when the vehicle accelerates, said suspension means including
• (a) means for connecting said inner portions of said front and rear structures at a primary pivot point (62) such that said inner portions of said front and rear structures can turn about said pivot point, said primary pivot point being at a selected elevation above the ground when said vehicle frame is stationary;
• (b) linkage means for pivotally interconnecting a first pivot point (37) on said inner portion of said rear structure with a second pivot point (26) on said inner portion of said front structure, said linkage means including at least one lever arm (12) having
• (i) a first end pivotally attached (37) to at least one of said first and second pivot points, and
• (ii) a second end,
• said linkage means permitting the position of said first pivot point with respect to said second pivot point to alter when the vehicle accelerates and said inner portions of said front and rear structures are upwardly displaced away from the ground and pivot about said primary pivot point;
• and,
• (c) resilient shock absorber means (42) mounted on said frame to dampen the movement of said front and rear structures when the vehicle accelerates and said inner portions of said front and rear structures are displaced upwardly away from the ground and pivot about said primary pivot point;
• said resilient shock absorber means including
• (i) a first end pivotally connected to said second end of said lever arm at a third pivot point (41) separate from said primary, first, and second pivot points, and
• (ii) a second end connected to said frame at a fourth pivot point (67), said third pivot point being a selected distance from said fourth pivot point when the vehicle is stationary;
• said linkage means, when the vehicle accelerates and said front and rear structures are upwardly displaced away from the ground, generating a force on said resilient shock absorber means which alters the distance between said third pivot point and said fourth pivot point, said resilient shock absorber means dampening the movement of said linkage means when the distance between said third and fourth pivot points is altered.