US Patent 7946599 Cross-linked variable piston air suspension

An air suspension includes first and second air spring assemblies that each include a piston airbag and a primary airbag. A first fluid connection connects one of a first piston airbag and a first primary airbag of the first air spring assembly to one of a second piston airbag and a second primary airbag of the second air spring assembly. A second fluid connection connects the other of the first piston airbag and the first primary airbag to the other of the second piston airbag and the second primary airbag. Air flow through the first and second fluid connections is passively controlled solely in response to road load inputs to reduce roll stiffness and improve articulation.