Patent ID: 7937934
Filing Date: 2011-05-10
Classification: B01D,F01N,F04B,Y02T

Abstract:
1. A metering pump assembly for admixing a fluid reduction agent from a supply container and a pressurized air flow into an exhaust gas flow of a combustion engine, the metering pump assembly comprising: an assembly housing for mounting proximate to the exhaust gas flow, the assembly housing being divided into a first housing part, a second housing part and a third housing part, each housing part defining a cavity, the second housing part being connected to both the first and third housing parts, the first housing part includes control and regulation electronics at least partially enclosed by the cavity thereof; a pre-mixer having at least a portion thereof within the assembly housing; a membrane pump at least partially enclosed by the cavity of the third housing part of the assembly housing and fluidly connected between the supply container and the pre-mixer by a conduit, a return conduit fluidly connected between a pre-flushing valve within the pre-mixer and the supply container; an electric motor at least partially enclosed by the cavity of the second housing part of the assembly housing generating a rotational output; a transmission at least partially enclosed by the cavity of the second housing part of the assembly housing converting the rotational output of the electric motor into translatory movement, the translatory movement driving the membrane pump to pump the reduction agent from the supply container into the pre-mixer, the pressurized air flow being in fluid communication with the pre-mixer and mixing with the reduction agent within the pre-mixer to form a reduction agent air mixture; and an exit conduit fluidly connecting the pre-mixer to the exhaust gas flow, the reduction air mixture being delivered through the exit conduit and into the exhaust gas flow.