GB1246546A - Improvements in metering arrangements for pneumatic conveying apparatus - Google Patents

Abstract

1,246,546. Feeding apparatus. NATIONAL RESEARCH DEVELOPMENT CORP. 16 Feb., 1970 [21 Feb., 1969], No. 9514/69. Heading AIM. [Also in Divisions B8 and G1] A metering device for diverting a predetermined quantity of solid material from the conveying airstream of a pneumatic conveyer comprises a perforate or mesh flap 9 interposable into the airstream to divert solid material into a container 11 resiliently suspended from the conveyer conduit 1, and means responsive to a predetermined downward movement of the container 11 due to the accumulation therein of diverted material to initiate withdrawal of the flap 9 from the airstream. A support frame 4 is clamped to the ends of the conduits 1 and a valve body 8 containing the flap 9 is connected by flexible ducts 5 to the conduits 1. The container 11 is rigidly connected to the valve body 8 and is suspended from the frame 4 by tension springs 19 hanging from levers 18 pivoted to the frame 4. A selector lever 23 moving over a dial 21 acts via a cam (24) (Fig. 1, not shown) on the levers 18 to adjust the spring preloading, and hence the load at which the container and the valve body move downwards from stops 25 on the frame 4. A bellcrank lever 30 on the pivot shaft of the flap 9 engages a stop 34 and a reset arm 32 on the frame 4. At the predetermined load, the valve body and container have moved downwards far enough for the lever 30 to clear the stop 34 and 32, allowing the flap 9 to move by gravity and/or spring bias to a position out of the airstream and closing the branch opening in the valve body. The container 11 has a counterbalanced bottom door 14 normally held closed by a latch 17 which is releasable manually or by a timer. In an animal feeding system, a series of metering devices in a pneumatic conveyer circuit fill their containers 11 in succession when the system is operated, the containers being subsequently emptied into food troughs.