Pneumatic conveyors

Claim 1

Apparatus for feeding particulate or powder material comprising: a hopper for the material, said hopper having an outlet, a valve comprising a body, said body having an annular wall, a plate engaging one end of said wall and defining an inlet to said body, and a plate engaging the other end of said wall and defining an outlet, an inlet pipe extending from said inlet of said body and connected to said outlet of said hopper, said inlet pipe and said inlet of said body having axes that are inclined to one another, an outlet pipe extending from said outlet exteriorly of said body, a valve member including a disc movable to open and close said inlet, means for moving said disc comprising a solenoid and a control rod connected to said disc and to said solenoid and extending from said disc through said inlet and tranSversely through said inlet pipe towards said solenoid, said solenoid being mounted exteriorly of said body, a one-way flat valve member at said outlet operable by a differential pressure thereacross between the pressure in said body and the pressure in said outlet pipe; said disc and said flat valve member being disposed coaxially of said body with said control rod extending axially of said inlet towards said solenoid so that the flow path in said body between said disc and flat valve is unobstructed, and, means for coupling said body downstream of said inlet to a gas supply.