Patent attributes
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 includes an assembly housing and a pre-mixer at least partially within the housing. A membrane pump within the housing is fluidly connected between the supply container and the pre-mixer. An electric motor generates a rotational output. A transmission converts the rotational output of the electric motor into translatory movement. The translatory movement drives the membrane pump to pump the reduction agent from the supply container into the pre-mixer. The pressurized air flow is in fluid communication with the pre-mixer and mixes with the reduction agent within the pre-mixer to form a reduction agent air mixture. An exit conduit fluidly connects the pre-mixer to the exhaust gas flow. The reduction air mixture is delivered through the exit conduit and into the exhaust gas flow.