Abstract: A diesel dosing system for a vehicle includes a control valve (31) controlling fluid flow to a dosing valve (32) for supplying fuel directly into an exhaust passage of the vehicle. A system pressure source (55) feeds the control valve. A shutoff valve (54) is fluidly connected to the pressure source downstream thereof and to the control valve upstream thereof. The shutoff valve permits bidirectional flow there-through. A connection (57) is between the shutoff valve and the control valve defining a fluid volume there-between. The shutoff valve permits fluid flow from the system pressure source through the connection and to the control valve during a regeneration phase of the system. Upon engine shutdown and based on fluid pressure in the volume, the shutoff valve opens so that fluid trapped in the volume will communicate with the pressure source thereby reducing the fluid pressure in the volume.

Abstract: A reductant delivery unit (16) is provided unit for selective catalytic reduction (SCR) after-treatment for vehicles. The unit includes a solenoid fluid injector (18) associated with an exhaust gas flow path (13). The injector has a fluid inlet (28) and a fluid outlet (30) with the fluid inlet receiving a source of urea solution and the fluid outlet communicating directly with the exhaust flow path so as to control injection of urea solution into the exhaust gas flow path. Supply structure (32) defines the fluid inlet and includes a cup (37) coupled to a body (18) of the injector and a supply tube (29) integral with the cup to define a single member. The supply tube is coupled with the source (27) of urea solution to deliver urea solution to the fluid inlet. The supply tube is heated by a heat source (33) so that an entire volume of the urea solution delivered to the fluid inlet is heated.

Abstract: A diesel dosing system for a vehicle includes a control valve (31) controlling fluid flow to a dosing valve (32) for supplying fuel directly into an exhaust passage of the vehicle. A system pressure source (55) feeds the control valve. A shutoff valve (54) is fluidly connected to the pressure source downstream thereof and to the control valve upstream thereof. The shutoff valve permits bidirectional flow there-through. A connection (57) is between the shutoff valve and the control valve defining a fluid volume there-between. The shutoff valve permits fluid flow from the system pressure source through the connection and to the control valve during a regeneration phase of the system. Upon engine shutdown and based on fluid pressure in the volume, the shutoff valve opens so that fluid trapped in the volume will communicate with the pressure source thereby reducing the fluid pressure in the volume.

Abstract: A reductant delivery unit (10) is provided for selective catalytic reduction (SCR) after-treatment for vehicles. The unit includes a solenoid fluid injector (10) constructed and arranged to be associated with an exhaust gas flow path (14) upstream of a SCR catalytic converter (17). The fluid injector has a fluid inlet (13) and a fluid outlet (15) with the fluid inlet being constructed and arranged to receive a source of urea solution and the fluid outlet being constructed and arranged to communicate directly with the exhaust flow path so as to control injection of urea solution into the exhaust gas flow path. An interface (24) is constructed and arranged to couple the fluid injector to the gas flow path. The interface defines a thermal barrier constructed and arranged to decoupled a body of the injector from exposure to heat in the exhaust gas flow path.