Leveling system with a single offset mounted air spring

Claim 2

A vehicle rear suspension leveling system comprising: a rear axle housing having wheel means on either end thereof, means on said axle housing defining a pair of spaced apart spring seats, a chassis frame cross member located above said axle housing having opposite end portions thereon, a pair of spaced apart primary spring means each having a first end thereon supported on one of said spring seats and an opposite end thereon supported on one of said cross member end portions, said spring means serving to yieldably maintain said chassIs cross member at a predetermined position above said axle housing under first vehicle load conditions, a differential housing on said axle housing located between the opposite ends thereof, differential gear means within said housing including a pinion member, a drive shaft extending from said differential housing adapted to be connected to power output means for driving said gear means to transfer power from the output means to said wheel assemblies, compressor means including a driven member operated by said differential pinion to compress air, a tubular air spring sleeve having upper and lower ends, said sleeve having rolling lobes at each end thereof; a piston sealed to each of said lobes including a bell-shaped outer surface for supporting each of said lobes for rolling movement with respect thereto, means connecting one of said pistons connected to said cross member at a point offset from the center of said cross member, the other of said pistons connected offset of said differential housing on side opposite to said differential pinion driven compressor, said sleeve having a length greater than its diameter to permit free, relative movement between said pistons in response to suspension movement, means to direct air from said compressor means into said air spring sleeve to vary the height thereof only when the vehicle is driven and to produce a spring force supplemental to that of said primary spring means, and means for controlling air flow from said compressor means to said air spring sleeve for automatically maintaining a predetermined height relationship between said chassis cross member and said axle housing in response to changes in vehicle load.

Claim 3

A vehicle leveling system for maintaining a predetermined height relationship between the sprung and unsprung mass portions at the rear and front of a vehicle comprising: front suspension means including a spring means for supporting the vehicle weight at the front thereof, a rear frame cross member directed generally perpendicularly to the longitudinal axis of the vehicle and including end portions thereon, side frame members connected to each of the end portions of said cross member, spaced rear spring means supporting said cross member, said cross member including a forwardly located seat portion thereon offset from the midportion of said cross member, unsprung suspension means located below said cross member including support means for said rear spring means thereon underlying said forwardly located seat portion on said cross member, a first air spring piston connected to said cross member seat portion, a second air spring piston connected to said support means, a tubular sleeve connected between each of said pistons including a rolling lobe on each end thereof supportingly received on each of said pistons, each of said rolling lobes being sealingly secured to said pistons to form a pressurizable air chamber within said sleeve between said first and second piston members, said sleeve having a length between said pistons greater than the diameter of said sleeve to define a spring column having reduced lateral stiffness whereby the spring will follow suspension motion between said cross member seat and said differential support means, said first and second pistons and said sleeve lobes supported thereon adjusting to relative movement between said cross member seat and said differential support member to maintain columnar force reactions on said pistons between said cross member, pressurizable air supply means, means for controlling flow of air from said pressurizable air supply means into said sleeve for inflating said sleeve to a predetermined pressure to compensate for load changes on the vehicle, said sleeve having crossed reinforcing cords therein formed at an angle greater than 40* when the pressure in said sleeve is below 15 psi, said sleeve cords increasing in angular relationship as the pressure in said sleeve is increasing to cause said sleeve length to foreshorten in response to load changes to compensate for front spring deflection so as to maintain the front of the vehicle parallel to ground.

Claim 4

A vehicle leveling system for maintaining a predetermined height relationship between the sprung and unsprung mass portions at the rear and front of a vehicle comprising: front suspension means including a spring means for supporting the vehicle weight at the front thereof, a rear frame cross member directed generally perpendicularly to the longitudinal axis of the vehicle and including end portions thereon, side frame members connected to each of the end portions of said cross member, spaced rear spring means supporting said cross member, said cross member including a forwardly located seat portion thereon offset from the midportion of said cross member, unsprung suspension means located below said cross member including support means for said rear spring means thereon underlying said forwardly located seat portion on said cross member, a first air spring piston connected to said cross member seat portion, a second air spring piston connected to said support means, a tubular sleeve connected between each of said pistons including a rolling lobe on each end thereof supportingly received on each of said pistons, each of said rolling lobes being sealingly secured to said pistons to form a pressurizable air chamber within said sleeve between said first and second piston members, said sleeve having a length between said pistons greater than the diameter of said sleeve to define a spring column having reduced lateral stiffness whereby the spring will follow suspension motion between said cross member seat and said differential support means, said first and second pistons and said sleeve lobes supported thereon adjusting to relative movement between said cross member seat and said differential support member to maintain columnar force reactions on said pistons between said cross member, pressurizable air supply means, means for controlling flow of air from said pressurizable air supply means into said sleeve for inflating said sleeve to a predetermined pressure to compensate for load changes on the vehicle, said sleeve having crossed reinforcing cords therein formed at an angle greater than 40* when the pressure in said sleeve is below 15 psi, said sleeve cords increasing in angular relationship as the pressure in said sleeve is increasing to cause said sleeve length to foreshorten in response to load changes to compensate for front spring deflection so as to maintain the front of the vehicle parallel to ground.

Claim 5

A vehicle leveling system for maintaining a predetermined height relationship between the sprung and unsprung mass portions at the rear of a vehicle comprising: a vehicle frame cross member directed generally perpendicularly to the longitudinal axis of the vehicle and including end portions thereon, side frame members connected to each of the end portions of said cross member, rear spring means supporting said cross member at the end portions thereon, said cross member including a fowardly located seat portion thereon offset from the midportion of said cross member, a differential housing located below said cross member including side support means thereon underlying said forwardly located seat portion on said cross member, a first air spring piston connected to said cross member seat portion, a second air spring piston connected to a side portion of said differential housing support surface, each of said pistons having a bell-shaped outer surface, a tubular sleeve connected between each of said pistons including a rolling lobe on each end thereof supportingly received on each of said bell-shaped piston surfaces, each of said rolling lobes being sealingly secured to said pistons to form a pressurizable air chamber within said sleeve between said first and second piston members, said sleeve having a length between said pistons greater than the diameter of said sleeve to define a spring column having reduced lateral stiffness whereby the spring will follow suspension motion between said cross member seat and said differential support means, said first and second pistons and said sleeve lobes supported thereon adjusting to relative movement between said cross member seat and said differential support member to maintain a columnar force reaction on said piston between said cross member support seat and said differential housing support means, pressurizable air supply means, means for automatically controlling flow of air from said pressurizable air supply means into said sleeve for inflating said sleeve to a predetermined pressure to compensate for load changes on the vehicle.

Claim 6

A vehicle leveling system for maintaining a predetermined height relationship between the sprung and unsprung mass portions at the rear of a vehicle comprising: a vehicle frame cross member directed generally perpendicularly to the longitudinal axis of the vehicle and including end portions thereon, side frame members connected to each of the end portions of said cross member, rear spring means supporting said cross member at the end portions thereon, said cross member including a fowardly located seat portion thereon offset from the midportion of said cross member, a differential housing located below said cross member including side support means thereon underlying said forwardly located seat portion on said cross member, a first air spring piston connected to said cross member seat portion, a second air spring piston connected to a side portion of said differential housing support surface, each of said pistons having a bell-shaped outer surface, a tubular sleeve connected between each of said pistons including a rolling lobe on each end thereof supportingly received on each of said bell-shaped piston surfaces, each of said rolling lobes being sealingly secured to said pistons to form a pressurizable air chamber within said sleeve between said first and second piston members, said sleeve having a length between said pistons greater than the diameter of said sleeve to define a spring column having reduced lateral stiffness whereby the spring will follow suspension motion between said cross member seat and said differential support means, said first and second pistons and said sleeve lobes supported thereon adjusting to relative movement between said cross member seat and said differential support member to maintain a columnar force reaction on said piston between said cross member support seat and said differential housing support means, pressurizable air supply means, means for automatically controlling flow of air from said pressurizable air supply means into said sleeve for inflating said sleeve to a predetermined pressure to compensate for load changes on the vehicle.

Claim 7

A vehicle rear suspension leveling system comprising: a rear axle housing, wheel means on said rear axle housing for supporting said axle housing, a vehicle frame including side members and a cross member, said cross member including rearwardly directed spring seats on either side thereof, a forwardly directed spring seat located intermediate said rearwardly located spring seats and offset from the longitudinal center of said cross member, spaced apart spring seats on said axle housing, first and second spring means interposed between said rearwardly directed frame spring seats and said axle housing spring seats for supporting said frame a predetermined trim height above said axle housing, a differential housing on said axle housing intermediate the ends thereof, said differential housing having a longitudinal surface defining a pinion bumper support surface thereon, a pinion bumper at the midpoint of said cross member operative to engage said support surface to control movement of said cross arm upon maximum compression of said first and second springs, a spring seat on one side of said differential housing at the nose thereof located in offset relationship to said pinion bumper support surface, a cylindrical air spring connected between said forwardly directed spring seat and said differential housing spring seat, said air spring including a pair of spaced apart piston members and an elongated sleeve to form a column support between said differential housing and said cross member, said air spring sleeve having rolling lobes thereon fastened to said pistons for defining a pressurizable air chamber, means for supplying air to said air spring and for exhausting air therefrom to produce a supplemental load carrying suppprt in addition to said springs for leveling load changes on said vehicle Frame, said air spring compensating for changes in the loading to maintain vertical clearance between said cross member and differential housing whereby the length of said pinion bumper can be foreshortened, said air spring having a length to diameter ratio to maintain a substantial longitudinal spring rate and a reduced lateral spring rate whereby the spring is stable to support changes in load and able to follow the suspension movement between said cross member and said differential housing without undue strain on the air spring.

Claim 8

A vehicle rear suspension leveling system comprising: a rear axle housing, wheel means on said rear axle housing for supporting said axle housing, a vehicle frame including side members and a cross member, said cross member including rearwardly directed spring seats on either side thereof, a forwardly directed spring seat located intermediate said rearwardly located spring seats and offset from the longitudinal center of said cross member, spaced apart spring seats on said axle housing, first and second spring means interposed between said rearwardly directed frame spring seats and said axle housing spring seats for supporting said frame a predetermined trim height above said axle housing, a differential housing on said axle housing intermediate the ends thereof, said differential housing having a longitudinal surface defining a pinion bumper support surface thereon, a pinion bumper at the midpoint of said cross member operative to engage said support surface to control movement of said cross arm upon maximum compression of said first and second springs, a spring seat on one side of said differential housing at the nose thereof located in offset relationship to said pinion bumper support surface, a cylindrical air spring connected between said forwardly directed spring seat and said differential housing spring seat, said air spring including a pair of spaced apart piston members and an elongated sleeve to form a column support between said differential housing and said cross member, said air spring sleeve having rolling lobes thereon fastened to said pistons for defining a pressurizable air chamber, means for supplying air to said air spring and for exhausting air therefrom to produce a supplemental load carrying suppprt in addition to said springs for leveling load changes on said vehicle Frame, said air spring compensating for changes in the loading to maintain vertical clearance between said cross member and differential housing whereby the length of said pinion bumper can be foreshortened, said air spring having a length to diameter ratio to maintain a substantial longitudinal spring rate and a reduced lateral spring rate whereby the spring is stable to support changes in load and able to follow the suspension movement between said cross member and said differential housing without undue strain on the air spring.

Claim 9

A vehicle suspension system comprising: front suspension means including spring means for supporting the vehicle weight of the front thereof, a rear axle housing, wheel means on said rear axle housing for supporting said axle housing, a vehicle frame including side members and a cross member, said cross member including rearwardly directed spring seats on either side thereof, a forwardly directed spring seat located intermediate said rearwardly located spring seats, spaced apart spring seats on said axle housing, first and second spring means interposed between said rearwardly directed frame spring seats and said axle housing spring seats for supporting said frame a predetermined trim height above said axle housing, a differential housing on said axle housing intermediate the ends thereof, said differential housing having a longitudinal surface defining a pinion bumper support surface thereon, a pinion bumper at the mid point of said cross member operative to engage said support surface to control movement of said cross member upon maximum compression of said first and second springs, a spring seat on one side of said differential housing at the nose thereof located in offset relationship to said pinion bumper support surface, an air spring connected between said forwardly directed spring seat and said differential housing spring seat, said air spring including a pair of spaced apart piston members and an elongated sleeve to form a column support between said spring seat on one side of said differential housing and said cross member, said air spring sleeve having rolling lobes thereon fastened to said pistons for defining a pressurizable air chamber, means for supplying air to said air spring and for exhausting air therefrom to vary the height thereof and to produce a supplemental load carrying support in addition to said springs for leveling load changes on said vehicle frame, said air spring compensating for changes in the loading to maintain vertical clearance between said cross member and differential housing whereby the length of said pinion bumper can be foreshortened, said air spring having a length to diameter ratio to maintain a substantial longitudinal spring rate and a reduced lateral spring rate whereby the spring is stable to support changes in load and able to follow the suspension movement between said cross member and said differential housing without undue strain on the air spring, said sleeve being made of reinforced rubber with layers of cord fabric crossed at an angle adjusted to cause the diametral growth of the sleeve on pressurization of the spring sleeve to match front suspension deflection so as to maintain the front of the vehicle parallel to ground.

Claim 10

A vehicle suspension system comprising: front suspension means including spring means for supporting the vehicle weight of the front thereof, a rear axle housing, wheel means on said rear axle housing for supporting said axle housing, a vehicle frame including side members and a cross member, said cross member including rearwardly directed spring seats on either side thereof, a forwardly directed spring seat located intermediate said rearwardly located spring seats, spaced apart spring seats on said axle housing, first and second spring means interposed between said rearwardly directed frame spring seats and said axle housing spring seats for supporting said frame a predetermined trim height above said axle housing, a differential housing on said axle housing intermediate the ends thereof, said differential housing having a longitudinal surface defining a pinion bumper support surface thereon, a pinion bumper at the mid point of said cross member operative to engage said support surface to control movement of said cross member upon maximum compression of said first and second springs, a spring seat on one side of said differential housing at the nose thereof located in offset relationship to said pinion bumper support surface, an air spring connected between said forwardly directed spring seat and said differential housing spring seat, said air spring including a pair of spaced apart piston members and an elongated sleeve to form a column support between said spring seat on one side of said differential housing and said cross member, said air spring sleeve having rolling lobes thereon fastened to said pistons for defining a pressurizable air chamber, means for supplying air to said air spring and for exhausting air therefrom to vary the height thereof and to produce a supplemental load carrying support in addition to said springs for leveling load changes on said vehicle frame, said air spring compensating for changes in the loading to maintain vertical clearance between said cross member and differential housing whereby the length of said pinion bumper can be foreshortened, said air spring having a length to diameter ratio to maintain a substantial longitudinal spring rate and a reduced lateral spring rate whereby the spring is stable to support changes in load and able to follow the suspension movement between said cross member and said differential housing without undue strain on the air spring, said sleeve being made of reinforced rubber with layers of cord fabric crossed at an angle adjusted to cause the diametral growth of the sleeve on pressurization of the spring sleeve to match front suspension deflection so as to maintain the front of the vehicle parallel to ground.

Claim 11

In a vehicle rear suspension leveling system a differential housing having a longitudinally projecting nose portion, differential gear means within said housing including a pinion member, cam means on said pinion member, a drive shaft extending from said differential housing adapted to be connected to power output means for driving said gear means to transfer power from the output means, pump means including an outer case, means supporting said case on one side of said nose portion means forming a port in said housing, means including a driven member in said pump case for compressing air, said driven member extending through said port into operative engagement with said cam means to operate said driven member only when a vehicle is driven, a cylindrical air spring connected between an offset portion of a vehicle frame cross member and the other side of said nose portion, means to direct air from said pump means to said air spring to produce a spring force supplemental to that of primary vehicle spring means, and means for automatically controlling air flow from said pump means to said spring for maintaining a predetermined height relationship between said chassis cross member and said axle housing in response to changes in vehicle load.

Claim 12

In a vehicle rear suspension leveling system a differential housing having a longitudinally projecting nose portion, differential gear means within said housing including a pinion member, cam means on said pinion member, a drive shaft extending from said differential housing adapted to be connected to power output means for driving said gear means to transfer power from the output means, pump means including an outer case, means supporting said case on one side of said nose portion means forming a port in said housing, means including a driven member in said pump case for compressing air, said driven member extending through said port into operative engagement with said cam means to operate said driven member only when a vehicle is driven, a cylindrical air spring connected between an offset portion of a vehicle frame cross member and the other side of said nose portion, means to direct air from said pump means to said air spring to produce a spring force supplemental to that of primary vehicle spring means, and means for automatically controlling air flow from said pump means to said spring for maintaining a predetermined height relationship between said chassis cross member and said axle housing in response to changes in vehicle load.

Claim 13

In a leveling system for a vehicle, a differential, first and second axle means extending in opposite directions laterally from said differential, a centralized housing for said differential, axle housing means for each of said axle means extending laterally from said differential housing, a wheel assembly disposed at each end of said axle housing means, means drivingly connecting each said axle means to the associated wheel assembly at each end of said axle housing means, a pair of spaced main spring seats secured at predetermined positions to said axle housing means, a vehicle chassis frame cross member spaced above said axle housing means and said differential housing, said cross member having opposite end portions aligned with said main spring seats on said axle housing, first main spring means having a first spring rate operatively disposed between a first of said spring seats and said aligned end portion of said cross member, second main spring means having a spring rate less than the spring rate of said first spring means operatively disposed between the second of said spring seats and the aligned end portion of said cross member, said differential housing having a nose portion which projects longitudinally with respect to said laterally extending axle housing means, said differential including an input gear means, drive shaft means drivingly connected to said input gear means, air compressor means secured on one side of said nose portion, said air compressor means including actuator means operated by said gear means to compress air, tubular air spring means having a variable height operatively connected to said air compressor means having upper and lower terminal ends to provide a variable spring force for raising and lowering said cross member with respect to said differential housing, means on the other side of said nose portion for mounting said air spring means to said differential housing, means offset from the center of said chassis frame cross member for securing the upper portion of said air spring means to said cross member so that said compressor means supplies compressed air to said air spring means when said vehicle is driven to produce a spring force supplemental to that of said main spring means for leveling said vehicle and for compensating for said differing spring rates of said main spring means and for urging said nose portion of said differential housing downwardly, and means for automatically controlling the air flow from said compressor means to said air spring means for maintaining a predetermined height relationship between said chassis frame cross member and said differential and axle housing means in response to changes in load on the vehicle.

Claim 14

In a leveling system for a vehicle, a differential, first and second axle means extending in opposite directions laterally from said differential, a centralized housing for said differential, axle housing means for each of said axle means extending laterally from said differential housing, a wheel assembly disposed at each end of said axle housing means, means drivingly connecting each said axle means to the associated wheel assembly at each end of said axle housing means, a pair of spaced main spring seats secured at predetermined positions to said axle housing means, a vehicle chassis frame cross member spaced above said axle housing means and said differential housing, said cross member having opposite end portions aligned with said main spring seats on said axle housing, first main spring means having a first spring rate operatively disposed between a first of said spring seats and said aligned end portion of said cross member, second main spring means having a spring rate less than the spring rate of said first spring means operatively disposed between the second of said spring seats and the aligned end portion of said cross member, said differential housing having a nose portion which projects longitudinally with respect to said laterally extending axle housing means, said differential including an input gear means, drive shaft means drivingly connected to said input gear means, air compressor means secured on one side of said nose portion, said air compressor means including actuator means operated by said gear means to compress air, tubular air spring means having a variable height operatively connected to said air compressor means having upper and lower terminal ends to provide a variable spring force for raising and lowering said cross member with respect to said differential housing, means on the other side of said nose portion for mounting said air spring means to said differential housing, means offset from the center of said chassis frame cross member for securing the upper portion of said air spring means to said cross member so that said compressor means supplies compressed air to said air spring means when said vehicle is driven to produce a spring force supplemental to that of said main spring means for leveling said vehicle and for compensating for said differing spring rates of said main spring means and for urging said nose portion of said differential housing downwardly, and means for automatically controlling the air flow from said compressor means to said air spring means for maintaining a predetermined height relationship between said chassis frame cross member and said differential and axle housing means in response to changes in load on the vehicle.