US 4,798,369 AGranted

Ultrasonic air spring system

AssigneeThe Firestone Tire & Rubber Company

InventorsWayne H. Geno, David A. Weitzenhof

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Abstract

An ultrasonic air spring system adapted to be mounted on a vehicle for absorbing road shocks exerted on the vehicle and for maintaining the vehicle body level with respect to the axles. An air spring includes an end plate and a piston sealingly connected to the open ends of the flexible elastomeric sleeve to form a pressurized fluid chamber therebetween. A transducer is mounted on the end plate within the fluid chamber and transmits ultrasonic signals through the fluid chamber toward the piston and picks up reflected signals therefrom. A signal is generated by the transducer in response to the reflected signals and fed to a microprocessor based control module. The control module determines whether the air requires fluid feed or exhaustion and will then implement control of inlet or exhaust valves to achieve a desired axial separation between the end plate and piston.

Claims6

Dependent claims

An ultrasonic air spring leveling system including:

(a) an end plate and a piston member located in a generally axial spaced relationship when in an at-rest position, said end plate and piston member being adapted to be mounted on spaced portions of a vehicle and movable towards and away from each other upon said vehicle encountering road shocks to absorb said shocks and to maintain said spaced vehicle portions at a predetermined spaced relationship when in said at-rest position;
(b) a fluid pressure chamber formed between said end plate and piston member by a flexible elastomeric sleeve having opposed open ends sealingly connected to said end plate and piston member;
(c) an ultrasonic transducer mounted on an inside surface of the end plate and located within the fluid pressure chamber for transmitting ultrasonic signals through the pressure chamber to the piston member and for picking up ultrasonic signals reflected from the piston member;
(d) electronic circuit means operatively connected to the transducer responsive to the picked up signals for generating a control signal;
and
(e) a source of pressurized fluid connected to the fluid pressure chamber and controlled by the control signal for regulating the amount of fluid within said pressure chamber to maintain a predetermined axial separation between the end plate and piston member when in said at-rest position.

3 more elements

Dependencies are inferred from the claim text.