Patent ID: 6572124
Filing Date: 2003-06-03
Classification: B60G,B62D

Abstract:
A lift axle control system for a vehicle having a forward condition providing forward movement of the vehicle and a reverse condition providing reverse movement of the vehicle, the vehicle including a chassis, a plurality of fixed axles supporting the chassis and having wheels normally in contact with the ground, a lift axle having wheels movable between a lifted position and a lowered position supporting the chassis, a lift axle mover configured to move the wheels of the lift axle between the lifted and lowered positions, and a source of pressurized fluid, the lift axle control system comprising,a housing including an inner surface defining a fluid passage, a port coupled to the housing and adapted to provide fluid communication between the fluid passage and the lift axle mover, a control valve configured to move between a lift position permitting the lift axle mover to move the wheels of the lift axle to the lifted position and a lower position controlling the flow of fluid between the source of pressurized fluid and the lift axle mover to move the wheels of the lift axle to the lowered position, a switch configured to move between a lift position controlling movement of the control valve to the lift position and a lower position controlling movement of the control valve to the lower position, the switch being configured to automatically move to the lift position when the vehicle is in the reverse condition, the switch being configured to automatically move to the lower position when the vehicle is out of the reverse condition, and a pilot valve supported by the housing and configured to control the movement of the control valve between the lift and lower positions.