Device for supplying a reducing agent to an exhaust-gas aftertreatment system

摘要

The invention relates to a device (10) for supplying to an exhaust-gas aftertreatment system a reducing agent (42), in particular a urea-water solution for the reduction of nitrogen oxides in the exhaust-gas flow of a diesel engine, having a tank (40) for the reducing agent (42) and having a delivery module (14) for delivering the reducing agent (42) out of the tank (40) via an in particular electrically heatable suction line (16). According to the invention, a) the suction line (16) which runs outside the tank (40) is connected to a pump sump (12) situated in the region of the tank base (44), b) an in particular electrically operated pump sump heater (30) is arranged in the region of the pump sump (12), c) at least one in particular electrically operated heating rod (36) extends into the tank (40), and d) at least one fill level sensor (18) runs outside the tank (40). The pump sump heater (30), the heated suction line (16), the heating rod (36) and an optional elastic compensating element (26) in the region of the pump sump (12) permit a substantially temperature-independent supply of the reducing agent (42) to an exhaust-gas aftertreatment system of a diesel engine. The pump sump (12) which is mounted on the bottom of the tank (40) furthermore makes it possible for the reducing agent (42), which must be available in the exact dose for correct execution of the SCR method, to be supplied virtually completely independent of position, and nevertheless uniformly, to the exhaust-gas aftertreatment system.

主权项

1. A device (10) for supplying a reducing agent (42) to an exhaust-gas aftertreatment system, having a tank (40) for the reducing agent (42) and having a delivery module (14) for conveying the reducing agent (42) out of the tank (40) via a suctioning line (16), characterized in that
a) the suctioning line (16), which is disposed at least partially outside the tank (40), is connected to a pump sump (12) situated in the region of a tank base (44), b) a pump sump heater (30) is arranged in a region of the pump sump (12), c) at least one heating bar (36) extends into the tank (40), and d) at least one fill level sensor (18) that is disposed at least partially outside the tank (40), wherein the at least one fill level sensor (18) includes a hose-like body with an interior channel in fluid communication with the pump sump (12) to receive reducing agent (42) from the pump sump (12).