Drop-axle suspension system

Claim 2

In an auxiliary axle suspension system for a wheeled vehicle comprising an axle mounting wheels along which the vehicle may travel, at least two leaf springs spaced from each other longitudinally along the length of said axle, means for connecting the leaf springs at about their ends to the vehicle, each leaf spring having its intermediate portion being secured by means to said axle, said leaf springs cooperating to normally bias said axle upwardly to raise the wheels mounted thereon above the surface along which the vehicle travels, at least one vertically flexible pneumatic chamber extending between the vehicle and said axle, and means for applying pneumatic pressure to said chamber to cause vertical elongation thereof thus biasing said axle downwardly against the force exerted by said springs to lower the wheels mounted thereon into contact with the vehicle travel surface; and wherein said axle is capable of carrying a load greater than 14,000 lbs., the improvement comprising at least two torque arms separated from each other longitudinally along the length of said axle and extending in the longitudinal direction of said vehicle between said axle and said respective means for connecting the leaf springs to the vehicle, said means connecting said leaf springs to said vehicle in a manner to allow said springs to slide longitudinally therewithin.

Claim 3

An auxiliary axle suspension system in accordance with claim 1 which includes means for connecting said torque arm to said axle, said torque arm being connected to said axle thereby.

Claim 4

An auxiliary axle suspeNsion system in accordance with claim 2 which includes at least two vertically flexible pneumatic chambers, each of said chambers being located between said vehicle and said intermediate portion of its respective leaf spring.

Claim 5

An auxiliary axle suspension system in accordance with claim 3 wherein each of said torque arms is connected to said axle by the same means which connects said intermediate portion of its respective leaf spring to said axle.

Claim 6

An auxiliary axle suspension system in accordance with claim 1 wherein said leaf springs are comprised of a plurality of leaves.

Claim 7

In a wheeled vehicle having longitudinally extending frame members in side-by-side relation and each frame member being disposed adjacent a respective side of said vehicle, first and second axles underlying said frame members and extending transversely thereof, said axles being spaced from each other longitudinally of said vehicle and each mounting wheels along which the vehicle may travel, means connecting said first axle to said frame members whereby said first axle provides a primary means of vehicle support and an axle suspension means for raising and lowering said second axle so as to raise or lower said wheels mounted thereon out of or into contact with the travel surface of said vehicle, the improvement comprising as said second axle and suspension system, an axle capable of carrying a load greater than 14,000 lbs. and the auxiliary axle suspension system defined in claim 1 wherein said respective means for connecting the leaf springs at about their ends to the vehicle in a manner to allow said springs to slide longitudinally within said means are bracket means extending substantially vertically from their respective frame members and being connected thereto.

Claim 8

A wheeled vehicle according to claim 6 which includes means for connecting said torque arms to said axle, each of said torque arms being rotatably connected by one of its ends thereby to said axle, the other end of each of said torque arms being rotatably connected to its respective corresponding frame member by the same bracket means that connects its corresponding leaf spring to said frame member.

Claim 9

A vehicle according to claim 7 which includes at least two vertically flexible pneumatic chambers, each of said chambers being located between said vehicle and said intermediate portion of the respective leaf spring.

Claim 10

A wheeled vehicle according to claim 8 wherein said longitudinally extending frame members are comprised of an upwardly and longitudinally extending vertical member having a longitudinal horizontal flange laterally extending from its lower end; wherein said bracket means are comprised of a lower vertically extending member to which said torque arm is rotatably connected and into which said ends of said leaf springs are slidably connected and an upper horizontal flange extending therefrom; and wherein said bracket means are connected to said frame members by abutment of the respective flanges of said frame members and bracket means, the abutting flange of said bracket means being its upper horizontal flange which extends beyond the abutting flange of said frame member, means located on either side of said upwardly and longitudinally extending vertical members of said frame members, each of said means being connected to its corresponding means on the other side of said upwardly and longitudinally extending vertical member by bolt means extending through said means and member, at least one of said means being an angled member having a leg abutting with and extending beyond the side of the horizontal laterally extending flange of said frame member opposite to the side abutted by the abutting horizontal flange of said bracket means and being bolted to the portion of said abutting horizontal flange of said bracket means extending beyond the abutting flange of said frame member through its corresponding beyond extending portion to thereby engage said abutting horizontal laterally extending flange of said framE member therebetween without having to bolt through said abutting frame member''s horizontal laterally extending flange.

Claim 11

In an auxiliary axle suspension system for a wheeled vehicle comprising at least one leaf spring, means for connecting the leaf spring at about its intermediate portion so as to be secured to an axle of said vehicle, said leaf spring being normally biased upwardly, at least one vertically flexible pneumatic chamber means, and means for applying pneumatic pressure to said chamber to cause vertical elongation thereof downwardly against the force exerted by said springs; and wherein said axle of said vehicle is capable of carrying a load greater than 14,000 lbs., the improvement comprising, at least one torque arm extending in the longitudinal direction of said vehicle and being connected by one end thereof to said means for connecting said leaf spring to said axle, the other end being connected to said means for connecting said leaf spring to about its end to said vehicle, and wherein said means for connecting the leaf spring at about its ends to the vehicle allows said spring to slide longitudinally therewithin.

Claim 12

In an auxiliary axle suspension system for a wheeled vehicle comprising at least one leaf spring, means for connecting the leaf spring at about its intermediate portion so as to be secured to an axle of said vehicle, said leaf spring being normally biased upwardly, at least one vertically flexible pneumatic chamber means, and means for applying pneumatic pressure to said chamber to cause vertical elongation thereof downwardly against the force exerted by said springs; and wherein said axle of said vehicle is capable of carrying a load greater than 14,000 lbs., the improvement comprising, at least one torque arm extending in the longitudinal direction of said vehicle and being connected by one end thereof to said means for connecting said leaf spring to said axle, the other end being connected to said means for connecting said leaf spring to about its end to said vehicle, and wherein said means for connecting the leaf spring at about its ends to the vehicle allows said spring to slide longitudinally therewithin.

Claim 13

In a wheeled vehicle having longitudinally extending frame members in side-by-side relation and each frame member being disposed adjacent a respective side of said vehicle, said frame members comprising an upwardly and longitudinally extending vertical member having a longitudinal horizontal flange laterally extending from its lower end; and also including first and second axles underlying said frame members and extending traversely thereof, said axles being spaced from each other longitudinally of said vehicle and each mounting wheels along which the vehicle may travel, means connecting said first axle to said frame members whereby said first axle provides a primary means of vehicle support and an axle suspension means for raising and lowering said second axle so as to raise or lower said wheels mounted thereon out of or in contact with the travel surface of said vehicle which comprises at least two leaf springs spaced from each other longitudinally along the length of said second axle, means for connecting the leaf springs at about their ends to the vehicle, each leaf spring having its intermediate portion being secured by means to said second axle, said leaf springs cooperating to normally bias said axle upwardly to raise the wheels mounted thereon above the surface along which the vehicle travels, at least one vertically flexible pneumatic chamber extending between the vehicle and said axle, and means for applying pneumatic pressure to said chamber to cause vertical elongation thereof thus biasing said axle downwardly against the force exerted by said springs to lower the wheels mounted thereon into contact with the vehicle travel surface, the improvement comprising at least two torque arms separated from each other longitudinally along the length of said second axle and extending in the longitudinal direction of said vehicle between said second axle and said respective means for connecting the ends of said leaf springs to the vehicle, said respective means connecting the ends of said leaf springs to said vehicle comprising a bracket means including a lower vertically extending member to which its respective torque arm is connected and into which the ends of the leaf springs are slidably connected and an upper horizontal flange extending therefrom; said respective means connecting the ends of said leaf springs to said vehicle being connected to said frame members by abutment of the respective flanges of said frame members and bracket means, the abutting flange of said bracket means being its upper horizontal flange which extends laterally beyond the abutting horizontal laterally extending flange of said frame member, means located on either side of said upwardly and longitudinally extending vertical members of said frame members, each of said means being connected to its corresponding means on the other side of said upwardlY and longitudinally extending vertical member by bolt means extending through said means and member, at least one of said means being an angled member having a leg abutting with and extending beyond the side of the horizontal laterally extending flange of said frame member opposite to the side abutted by the abutting horizontal flange of said bracket means and being bolted to the portion of said abutting horizontal flange of said bracket means extending beyond the abutting flange of said frame member through its corresponding beyond extending portion to thereby engage said abutting horizontal laterally extending flange of said frame member therebetween without having to bolt through said abutting frame member''s horizontal laterally extending flange.

Claim 14

In a wheeled vehicle having longitudinally extending frame members in side-by-side relation and each frame member being disposed adjacent a respective side of said vehicle, said frame members comprising an upwardly and longitudinally extending vertical member having a longitudinal horizontal flange laterally extending from its lower end; and also including first and second axles underlying said frame members and extending traversely thereof, said axles being spaced from each other longitudinally of said vehicle and each mounting wheels along which the vehicle may travel, means connecting said first axle to said frame members whereby said first axle provides a primary means of vehicle support and an axle suspension means for raising and lowering said second axle so as to raise or lower said wheels mounted thereon out of or in contact with the travel surface of said vehicle which comprises at least two leaf springs spaced from each other longitudinally along the length of said second axle, means for connecting the leaf springs at about their ends to the vehicle, each leaf spring having its intermediate portion being secured by means to said second axle, said leaf springs cooperating to normally bias said axle upwardly to raise the wheels mounted thereon above the surface along which the vehicle travels, at least one vertically flexible pneumatic chamber extending between the vehicle and said axle, and means for applying pneumatic pressure to said chamber to cause vertical elongation thereof thus biasing said axle downwardly against the force exerted by said springs to lower the wheels mounted thereon into contact with the vehicle travel surface, the improvement comprising at least two torque arms separated from each other longitudinally along the length of said second axle and extending in the longitudinal direction of said vehicle between said second axle and said respective means for connecting the ends of said leaf springs to the vehicle, said respective means connecting the ends of said leaf springs to said vehicle comprising a bracket means including a lower vertically extending member to which its respective torque arm is connected and into which the ends of the leaf springs are slidably connected and an upper horizontal flange extending therefrom; said respective means connecting the ends of said leaf springs to said vehicle being connected to said frame members by abutment of the respective flanges of said frame members and bracket means, the abutting flange of said bracket means being its upper horizontal flange which extends laterally beyond the abutting horizontal laterally extending flange of said frame member, means located on either side of said upwardly and longitudinally extending vertical members of said frame members, each of said means being connected to its corresponding means on the other side of said upwardlY and longitudinally extending vertical member by bolt means extending through said means and member, at least one of said means being an angled member having a leg abutting with and extending beyond the side of the horizontal laterally extending flange of said frame member opposite to the side abutted by the abutting horizontal flange of said bracket means and being bolted to the portion of said abutting horizontal flange of said bracket means extending beyond the abutting flange of said frame member through its corresponding beyond extending portion to thereby engage said abutting horizontal laterally extending flange of said frame member therebetween without having to bolt through said abutting frame member''s horizontal laterally extending flange.

Claim 15

An auxiliary axle suspension system according to claim 1 wherein said axle is capable of carrying a load of 20,000 lbs.