US 2003/0111810 A1 · Lift axle air pressure transfer control apparatus

Abstract

A lift-type axle/suspension system of a heavy-duty vehicle includes ride air springs for providing vehicle load support when the system is lowered, and one or more lift air springs for selectively raising the system when such additional load support is unnecessary or when greater vehicle maneuverability is desired. An apparatus integrates and simultaneously controls the operating systems for the lift and ride air springs. The control apparatus includes a plurality of conduits and valves which enable pressurized air from the lift air springs to be rapidly provided to the ride air springs when the system is being lowered. The additional air supplements the normal source of air from the vehicle compressed air source to ensure sufficient and timely air for smooth and efficient operation of the ride air springs without excessive buckling or folding, thus maintaining adequate overall vehicle air pressure needed for operating other vehicle components.

Claims10

Dependent claims

A vehicle air-ride lift axle/suspension system, said system including at least one lift air spring for raising said axle/suspension system off the ground and at least one ride air spring for supporting a vehicle load when the axle/suspension system is lowered to the ground, said vehicle further including a source of compressed air and an operating system for each one of said lift air spring and said ride air spring, wherein the improvement comprises:

means for providing air from said deflating lift air spring to said inflating ride air spring when said axle/suspension system is being lowered, so that the ride air spring is sufficiently inflated during the lowering process.

A method of conveying compressed air from a lift air spring to a ride air spring of a vehicle air-ride lift axle/suspension system, said system including at least one of said lift air springs for raising said axle/suspension system off the ground and at least one of said ride air springs for supporting a vehicle load when the axle/suspension system is lowered to the ground, said vehicle further including a source of compressed air and an operating system for each one of said lift air spring and said ride air spring, said method including the steps of:

a) closing a valve interposed in a lift air spring conduit pneumatically connected to and extending between said vehicle compressed air source and said lift air spring;
b) simultaneously enabling air to flow from said lift air spring, through said lift air spring valve and out of an exhaust port of the valve, wherein a portion of said exhausted air passes at a restricted rate of flow through a choke valve pneumatically connected at one of its ends to said lift air spring valve exhaust port and at the other one of its ends to atmosphere, and wherein another portion of said exhausted air flows through a transfer conduit pneumatically connected at one of its ends to the exhaust port and at the other one of its ends to a ride air spring conduit pneumatically connected to and extending between said ride air spring and said vehicle compressed air source;
and
c) a one-way check valve interposed in said transfer conduit enabling said another portion of air to flow completely through said transfer conduit, into said ride air spring conduit and into said ride air spring during lowering of the vehicle axle/suspension system, so that the ride air spring is rapidly and sufficiently inflated during said lowering of said axle/suspension system.

1 more element

Dependencies are inferred from the claim text.

Lift axle air pressure transfer control apparatus

Life of this patent

Lift axle air pressure transfer control apparatus

Life of this patent

Abstract

Claims10