A vehicle comprising a group of several axles carrying the chassis by means of suspension springs using the pressure of a fluid

摘要

1511524 Tandem axle suspensions DAIMLERBENZ AG 24 July 1975 [26 July 1974] 31006/76 Heading B7D In a vehicle having a superstructure supported on driven and undriven tandem axles 211, 212 by air springs 213, 214 connected to a level regulating valve 217, the load carried by the driven axle 211 is kept at a maximum to avoid slipping of the driving wheels by connecting the spring 213 to the level regulating valve 217 through a cut-off valve 233 which prevents release of air from the spring 213 when the vehicle load decreases until the spring 214 on the undriven axle 212 has been fully relieved of load. A by-pass valve 237 opens whenever the level regulating valve 217 connects the springs to an accumulator 218 so that air can be admitted to the spring 213 when the vehicle load increases. A relief value 241 prevents excessive pressures in the spring 213. In another embodiment the arrangement according to the invention is combined with one in which pressurization of the spring on the undriven axle is prevented unless the spring on the driven axle is at full pressure. This system also includes separate levelling values for each axle and a manual control valve by means of which the level regulating valves can be over-ridden.