Abstract: The invention relates to a vehicle air supply system adaptable to occasionally supply large volumes of air at relatively low pressure for purposes such as tire inflation. The system has a compressor, an air dryer, a reservoir adapted to receive air from the compressor via the air dryer, and a controller operable to cause a standard regeneration of the air dryer when a predetermined system condition is met. The controller is also operable to cause an intermediate regeneration of the air dryer in advance of the predetermined system condition being met. The controller is further operable to inhibit the intermediate regeneration. The controller is operable so as to prevent saturation of an air dryer desiccant in circumstances where the compressor is on load for an extended period of time and likely to be pumping a large volume.

Abstract: An air dryer desiccant cartridge, the cartridge comprising a base having an inlet and an outlet, and a casing connected to the base to define a cavity there between, wherein the cavity contains a filter and a desiccant, the filter being arranged upstream of the desiccant such that during normal operation fluid flow entering the cartridge through the inlet passes through the filter and then on to the desiccant before reaching the outlet, and during purging of the cartridge purge flow entering the outlet passes through the desiccant before reaching the filter, wherein further the cartridge includes a valve operable to permit a portion of the purge flow to bypass the filter.

Abstract: An air dryer cartridge (10) is provided with an inlet connectable to a compressed air source, an outlet connectable to a reservoir and a desiccant (18) provided intermediate the inlet and outlet adapted to remove moisture from air passing through the air dryer cartridge (10), wherein the air dryer cartridge (10) further includes a filter (20) to capture oil droplets present in air received from the source, and wherein further the filter (20) is positioned downstream of the desiccant (18).

Abstract: A rotating vane vacuum pump has a secondary inlet (4) which permits additional suction after the primary inlet (3) has closed.