High speed air nozzle with mechanical valve for particulate systems

A method of supplying a predetermined amount of particulate material from a hopper, comprising:

• locating a conduit to extend from the hopper, the particulate material in the hopper having a hopper bulk density;
• conveying with a conveyor the particulate material in the hopper toward a nozzle assembly attached to the conduit, the nozzle assembly having a porous nozzle with an inlet cross sectional area defining an inlet cross sectional area and an outlet defining an outlet cross sectional area and the porous nozzle having an inner periphery thereof;
• sizing the inlet cross sectional to be larger than the outlet cross sectional area;
• applying an air boundary to the inner periphery of the porous nozzle to increase the compression ratio of the porous nozzle such that the flow of particulate material does not seize as it progresses through the nozzle assembly;
• dispensing particulate material through the conduit with the conveyor through the nozzle assembly during a supplying operation, the particulate material having an exit bulk density as it leaves the nozzle assembly, wherein the particulate material hopper bulk density is substantially the same as the exit bulk density;
• and
• controlling the flow of particulate material from the nozzle assembly with a mechanical valve.

A method of supplying developer material from a hopper, comprising:

• extending a conduit from the hopper, the developer material in the hopper having a hopper bulk density;
• conveying with an auger the developer material in the hopper toward a nozzle assembly attached to the conduit, the nozzle assembly having a porous nozzle with an inlet cross sectional area and an outlet defining an outlet cross sectional area, the porous nozzle having an inner periphery, wherein the inlet cross sectional area is larger than the outlet cross sectional area;
• applying an air boundary to the inner periphery of the porous nozzle to increase the compression ratio of the porous nozzle such that the flow of developer material does not seize as it progresses through the nozzle assembly, wherein the air boundary layer is continuously applied to the inner periphery of the porous nozzle during the supplying operation and between each supplying operation;
• supplying developer material through the conduit with the auger through the nozzle assembly during a supplying operation, wherein the auger is sized with respect to the conduit such that the rate at which particulate material travels through the conduit is substantially the same rate at which particulate material exits the nozzle, the developer material having an exit bulk density as it leaves the nozzle assembly, wherein the developer material hopper bulk density is substantially the same as the exit bulk density;
• and
• controlling the flow of developer material from the conduit with a mechanical valve, the nozzle assembly being part of the mechanical valve and is slidably supported with respect to the conduit.