Patent ID: 8215100

Claim:
An exhaust treatment device, comprising: a housing; an injector disposed within the housing to deliver an injection fluid into a flow of exhaust; at least one fluid supply passage disposed within the housing and being in fluid communication with the injector to supply the injector with injection fluid; at least one purge passage disposed within the housing and being in fluid communication with the injector to supply the injector with a purge fluid; and a first valve element mounted to the housing and being disposed at an entrance of the at least one purge passage, the entrance of the purge passage being formed by a periphery of the housing, and the first valve element being configured to provide a unidirectional flow of purge fluid to the at least one purge passage, wherein the at least one purge passage is in fluid communication with the injector via the at least one fluid supply passage, and the at least one fluid supply passage includes a pilot supply passage and a main supply passage.