Patent ID: 7699073

Claim:
A soft start device for compressed air systems, comprising; a primary inlet by way of which compressed air may be supplied at a primary pressure to a valve circuit having valves including a principal valve, said primary inlet being able to be coupled with a secondary outlet, able to be coupled with at least one load, by way of the valve circuit, at which the compressed air may be removed at a secondary pressure, the secondary pressure being less than or equal to the primary pressure, said principal valve of the normally closed type 2/2 being placed between the primary inlet and the secondary outlet, said principal valve being able to be shunted by a bypass, said bypass including a choke device, said principal valve and said choke device together with further of the valves of the valve circuit being so connected together that with said principal valve initially turned off during a starting operation with said principal valve initially closed compressed air is applied to the secondary outlet at a gradually increasing secondary pressure less than the primary pressure, until as from a predetermined relationship between the secondary and primary pressures a switching operation of said principal valve into its open position takes place so that compressed air passes at the primary pressure to the secondary outlet, and the valve circuit is adapted to be set in such a standard venting switching setting that the compressed air in the valve circuit is vented through a combination of venting exits of the valves of the valve circuit, wherein the valves of the valve circuit are operatively coupled with each other in a combination of series and shunt connections so that, in addition to the standard venting switching setting, a plurality of further venting switching settings is possible, the further venting switching settings venting the compressed air in the valve circuit through a different combination of venting exits of the valves than the standard switching setting, the further venting switching settings resulting when, in the actuating operation normally causing the standard venting switching setting, a fault in function existing in any one of the valves prevents the compressed air from being vented from the valve circuit using the standard venting switching setting.