DOSER MECHANISMS

A doser mechanism includes a cylindrical shell, an auger conveyor, and a check valve. The cylindrical shell includes a hollow cylinder and an end plate. The hollow cylinder at least partially defines an internal enclosure extending between first and second ends of the hollow cylinder, a first opening at the first end, and a second opening through a thickness of the hollow cylinder. The end plate covers the second end. The auger conveyor includes an auger at least partially extending through the internal enclosure through the first end. The check valve has a valve member configured to selectively cover the second opening. The check valve may cause the valve member to move between a rest position and an open position to cover or expose the second opening in response to a magnitude of a force applied to the valve member from the internal enclosure through the second opening.