Vehicle height adjusting system

Abstract

Abstract A vehicle suspension system for a trailer (2) comprises a plurality of suspension units (7). Under the normal operating condition of the suspension system, air is supplied from a source (8) to the suspension units by way of level sensing valves (16 and 18). In accordance with the invention, manually operative control means (20, 30) is provided to override operation of the suspension units (7) by the sensing valve (16 and 18), and to permit manual supply of air to and venting of air from the suspension units (7), to enable the height of the vehicle to be manually adjusted. Means is provided to ensure that the suspension system is returned to its automatic operating condition as a result of the vehicle being driven. In the first embodiment this is afforded by a valve (20) which is switched when the braking system of the vehicle is actuated: in the second embodiment the valve (22) is switched by an electrical signal, which may be obtained from the vehicle tachograph, or from actuation of the vehicle braking light, whilst in the third embodiment the suspension system is returned to its automatic mode in consequence of the unplugging of the manually operative control means (38b) from an inlet socket (34b).

Inventors

• 👤 Colin Ford Ross

Bibliographic Details