Abstract: To provide a reducing agent supply apparatus that makes it hard to refill the pump side with a liquid reducing agent upon completion of the suck back control of the liquid reducing agent and a method for control the reducing agent supply apparatus. The method for controlling the reducing agent supply apparatus pressure-feeds the liquid reducing agent in a storage tank using a pump and injects the liquid reducing agent into an exhaust passage of the internal combustion engine through a reducing agent injection valve when the internal combustion engine is operating and, when the internal combustion engine stops, sucks the liquid reducing agent remaining in a reducing agent supply path back to the storage tank, in which the suck back control starts when the internal combustion engine stops and, when the suck back control ends, a reducing agent passage interconnecting the pump and the storage tank is opened to air.

Abstract: To provide a reducing agent supply apparatus that makes it hard to refill the pump side with a liquid reducing agent upon completion of the suck back control of the liquid reducing agent and a method for control the reducing agent supply apparatus. The method for controlling the reducing agent supply apparatus pressure-feeds the liquid reducing agent in a storage tank using a pump and injects the liquid reducing agent into an exhaust passage of the internal combustion engine through a reducing agent injection valve when the internal combustion engine is operating and, when the internal combustion engine stops, sucks the liquid reducing agent remaining in a reducing agent supply path back to the storage tank, in which the suck back control starts when the internal combustion engine stops and, when the suck back control ends, a reducing agent passage interconnecting the pump and the storage tank is opened to air.

Abstract: [Problem] To provide a reducing agent injection valve abnormality detection unit capable of precisely determining whether or not a reducing agent injection valve is abnormally stuck, and a reducing agent supply apparatus.

Abstract: [Problem] To provide a reducing agent injection valve abnormality detection unit capable of precisely determining whether or not a reducing agent injection valve is abnormally stuck, and a reducing agent supply apparatus.

Abstract: A reducing agent injection device is equipped with a storage tank that houses a reducing agent, a pump that pressure-feeds the reducing agent, a reducing agent injection valve that injects the reducing agent pressure-fed by the pump into the inside of an exhaust pipe of an internal combustion engine, a supply path that interconnects the pump and the reducing agent injection valve, and a pressure sensor that is disposed in the supply path. The reducing agent injection device is configured such that it can suck, into the inside of the supply path, a gas inside the exhaust pipe via an injection hole in the reducing agent injection valve by subjecting the inside of the supply path to depressurization processing. An abnormality detection device detects clogging of the reducing agent injection valve in the reducing agent injection device and includes a clogging determination component.

Abstract: A reducing agent injection device is equipped with a storage tank that houses a reducing agent, a pump that pressure-feeds the reducing agent, a reducing agent injection valve that injects the reducing agent pressure-fed by the pump into the inside of an exhaust pipe of an internal combustion engine, a supply path that interconnects the pump and the reducing agent injection valve, and a pressure sensor that is disposed in the supply path. The reducing agent injection device is configured such that it can suck, into the inside of the supply path, a gas inside the exhaust pipe via an injection hole in the reducing agent injection valve by subjecting the inside of the supply path to depressurization processing. An abnormality detection device detects clogging of the reducing agent injection valve in the reducing agent injection device and includes a clogging determination component.

Abstract: There are provided a control unit and a control method for a reductant supply system, which are capable of reducing energy consumption by immediately stopping heating means in the case of entering an idling stop mode. A control unit which performs control of a reductant supply system includes an idling stop determination portion that determines whether an internal combustion engine is stopped by idling stop control that automatically stops the internal combustion engine, a heating means operation determination portion that determines whether the heating means provided in the reductant supply route that supplies the liquid reductant to the reductant injection valve is in operation, and a heating means control portion that stops operation of the heating means in a state where the internal combustion engine is automatically stopped and the heating means is in operation.