Device and method for regulating flow of particulate material, especially small flows of fine powder

A device for regulating the flow of particulate material, comprising:

• a valve housing having aligned first and second bores,
• a first, inlet conduit mounted in said first bore and having an outlet end nozzle with an elongated cross section which has a major and a minor axis,
• a second, outlet conduit rotatably mounted in said second bore for rotation about the axis of the second conduit and generally axially aligned with the first conduit, and having an inlet end nozzle of elongated crass section,
• said nozzles being sufficiently close to each other that said inlet end nozzle of the second conduit can receive at least a portion of a particulate material flow exiting said outlet end nozzle of the first conduit,
• a chamber formed in said valve body and surrounding the said inlet end nozzle of the second conduit for receiving particulate material which exits the outlet end nozzle of the first conduit and is not received into the inlet end nozzle of the second conduit, and
• means for adjusting the rotational relationship of the said inlet end nozzle to the said outlet end nozzle about the axis of at least one of the said bores, thereby to adjust the flow of particulate material between a maximum flow position where the cross-sections of the nozzles are in rotational alignment, and a minimum flow position at a substantial angle to the first position.

A method for regulating the flow of particulate material comprising:

• feeding the material with a carrier gas through a first conduit to exit at an outlet end thereof;
• receiving a part of the material into an inlet end of a second conduit which is generally aligned with the first conduit, the said ends being sufficiently adjacent for the second conduit inlet end to receive at least a portion of the material exiting the first conduit outlet end;
• and
• adjusting the lateral relationship of the adjacent ends of the conduits so that the amount of material flowing into the second conduit is adjusted, while recycling the material which does not flow into the second conduit back to a supply source.

A device for regulating the flow of particulate material, comprising:

• a first, inlet conduit having an outlet end,
• a second, outlet conduit generally aligned with the first conduit and having an inlet end sufficiently close to the said outlet end of the first conduit as to be capable of receiving at least a portion of a particulate material flow exiting said outlet end,
• a chamber surrounding the said inlet end for receiving particulate material which exits the outlet end of the first conduit and is not received into the inlet end of the second conduit, and
• means for adjusting the lateral relationship of the said inlet end of the second conduit to the said outlet end of the first conduit to change the area of the said inlet end exposed to the said outlet end thereby to adjust the flow of particulate material through the second conduit, wherein the first conduit is connected to a source of particulate material and of a carrier gas, and wherein said chamber is also connected to the source of particulate material through a by-pass tube.