US Patent 9545616 Method and apparatus for applying particulate

A particulate feeding apparatus for applying particulate, such as super-absorbent materials, to a substrate, such as a fibrous web. A feeder tube for the powder and a rotary gate valve, including one or more holes is provided. This structure may then intermittently feed particulate to an eductor or venturi nozzle. The rotary valve provides an intermittent supply of particulate to a relatively low-pressure zone at the nozzle formed by the venturi action of the passing air stream and the particulate may be distributed precisely where desired. A process for delivering powder to a substrate in precise amounts and distribution patterns is also disclosed.