A tank cover of a urea tank for an SCR aftertreatment system is provided with an air hole, a gas inlet hole, a gas discharge hole, a first constant pressure check valve and a second constant pressure check valve. The tank cover is mounted at a liquid injection port of a tank body of the urea tank. The air hole is provided in a portion of the tank cover corresponding to the liquid injection port. The gas inlet hole and the gas discharge hole are provided in the portion of the tank cover corresponding to the liquid injection port. An inlet of the first constant pressure check valve is butted with the air outlet hole. An inlet of the second constant pressure check valve is butted with the air inlet hole.

A system and apparatus for improving ventilation of a fluid system is disclosed herein. An apparatus for improving ventilation of a fluid storage tank includes a hollow member having a sidewall and an opening formed in the sidewall and an air-permeable membrane extending at least partially across the opening. The membrane permits the passage of air across the membrane and restricts the passage of fluid across the membrane.

In accordance with one aspect of the present disclosure, an accumulator is provided for an engine exhaust treatment system. The accumulator includes a container, an inlet portion for receiving exhaust treatment fluid, a conduit in communication with the inlet portion of the container to withdraw exhaust treatment fluid from the inlet portion, and an outlet portion configured to receive exhaust treatment fluid from the inlet portion and having an outlet for discharging exhaust treatment fluid. The accumulator includes a weir separating the inlet portion and the outlet portion that permits exhaust treatment fluid in the inlet portion to flow into the outlet portion.

A device includes at least one tank having a tank bottom and a delivery unit for a liquid. The delivery unit is disposed in a chamber on the tank bottom and the chamber includes at least one heater. The tank preferably has at least one local ventilation heater extending from a discharge for liquid on the tank bottom over at least one tank side to the vicinity of a tank top.

Provided is a breather pipe structure for a liquid reducing agent storage tank which ensures that a liquid reducing agent can be supplied without trouble even if a breather pipe in the liquid reducing agent storage tank is clogged with frozen liquid reducing agent. In a breather pipe structure for a liquid reducing agent storage tank (10) which stores a liquid reducing agent (5) and which has a breather pipe (20) for introducing/discharging air attached on top of the liquid reducing agent storage tank (10), a lower end (20c) of the breather pipe (20) in the liquid reducing agent storage tank (10) is arranged to extend along a liquid reducing agent defrosting piping (16) provided in the liquid reducing agent storage tank (10).

An injection device for diesel exhaust fluid includes a cylinder, a stopper, and an air tube. The cylinder encloses a receiving space. The cylinder has an opening at the bottom end. The stopper is pipe-shaped and has a stopping portion and a top portion at two opposite ends thereof. The stopper is arranged in the receiving space and is movable along the longitudinal direction of the cylinder. the stopping portion selectively plugs the opening of the cylinder so that fluid in the receiving space is unable to flow out via the opening. The air tube is inserted through the stopper and the opening of the cylinder to communicate with exterior. The air tube is positioned to the cylinder near the opening so that the air tube may not move with the stopper.

An injection device for diesel exhaust fluid includes a cylinder, a stopper, and an air tube. The cylinder encloses a receiving space. The cylinder has an opening at the bottom end. The stopper is pipe-shaped and has a stopping portion and a top portion at two opposite ends thereof. The stopper is arranged in the receiving space and is movable along the longitudinal direction of the cylinder. the stopping portion selectively plugs the opening of the cylinder so that fluid in the receiving space is unable to flow out via the opening. The air tube is inserted through the stopper and the opening of the cylinder to communicate with exterior. The air tube is positioned to the cylinder near the opening so that the air tube may not move with the stopper.

The invention relates to a line termination element (4) for a ventilation outlet of a fluid container (5), having a main body (2) which is formed as a closure element for a free end (3) of the ventilation outlet and which is cross-sectionally matched to the cross section of the ventilation outlet, comprising at least one flow passage as an insect barrier, which flow passage is smaller than a mouth cross section (17) of the ventilation outlet, and also at least one valve body (10), which, in a first position, closes off the mouth cross section (17) of the ventilation outlet and, in a second position, opens up the mouth cross section (17) of the ventilation outlet.

Disclosed is a urea injection device for a selective catalyst reduction device. The urea injection device for a selective catalyst reduction device serves to inject urea into a urea tank through a urea injection port and a urea injection line that connects the urea injection port and the urea tank. The urea injection device may include: i) a leveling pipe which is connected with the urea tank, ii) a separator which is installed to be connected with the leveling pipe, and connected to the urea injection port through a gas recirculation line, iii) a gas vent line which is connected with the separator, and iv) a check valve which is installed in the gas vent line.

A machine body comprises a sieving frame having a bottom plate. The machine body comprises an engine. The machine body comprises an exhaust gas cleaning apparatus that executes reduction treatment on a predetermined oxide in an exhaust gas of the engine by injecting a liquid reducing agent. The machine body comprises a reducing agent tank that stores a liquid reducing agent. The machine body comprises a reducing agent pump that feeds the liquid reducing agent stored in the reducing agent tank to the exhaust gas cleaning apparatus. The machine body comprises a cooling fan. The machine body is disposed on the bottom plate of the slewing frame and comprises an opening section that takes in outside air that cools the reducing agent pump by driving the cooling fan. The machine body comprises a duct section that leads the outside air taken from the opening section to the cooling fan.