| 主权项 |
1. A metering device for metering granular product into a pressurized conduit of a pneumatic conveyor, the device comprising:
a tubular housing with a smooth inner wall surface, the housing oriented such that a housing axis thereof is oriented substantially vertically; an intake opening defined in an intake wall of the housing, and a discharge opening defined in a discharge wall of the housing opposite the intake wall, and first and second blank walls between the intake and discharge openings; an upper hub rotatably mounted in an upper end of the housing above the intake and discharge openings, and an upper seal sealing a perimeter of the upper hub to the inner wall surface of the housing; a lower hub rotatably mounted in a lower end of the housing below the intake and discharge openings, and a lower seal sealing a perimeter of the lower hub to the inner wall surface of the housing, wherein an upper surface of the lower hub slopes downward from in inner edge thereof adjacent to the housing axis to an outer edge thereof adjacent to the housing such that granular product flows down the sloped upper surface; a drive shaft extending along the housing axis through the upper and lower hubs and fastened to the upper and lower hubs such that the hubs rotate with the drive shaft; a meter drive connected to rotate the drive shaft at a selected rotational speed; a plurality of flexible blades, each blade extending between the upper and lower hubs and having an outer edge wiping the inner wall surface of the housing as the hubs rotate and an inner edge substantially sealed to the drive shaft such that a substantially sealed blade chamber is formed between adjacent blades and one of the blank walls as the hubs rotate. |
