Powder hopper for electrostatic powder spraying apparatus

Claim 1

A powder hopper for electrostatic powder spraying apparatus comprising: a. a hopper body having an upper cylindrical chamber and a communicating lower conical chamber; b. a fluidizing air chamber operatively mounted in the lower end of said hopper body and having an open upper end communicating with the lower end of said conical chamber; c. means for conveying pressurized air into said fluidizing air chamber for flow into the lower conical chamber to agitate and fluidize the powder in the lower end of the conical chamber; d. a diffuser membrance operatively mounted over the open upper end of said fluidizing air chamber for evenly distributing the pressurized air flowing from said fluidizing air chamber into said conical chamber; e. pump means comprising a plurality of annularly disposed venturi powder pumps operatively mounted in said conical chamber in a position spaced above and adjacent to said diffuser membrane; f. said venturi powder pump means having an intake means for admitting fluidized powder from said conical chamber; g. means operatively connected to one end of said venturi powder pump means for supplying pressurized air to said venturi powder pump means to draw fluidized powder through said intake means into the venturi pump means; and, h. means operatively connected to the other end of said venturi powder pump means for conveying the pressurized air and fluidized powder from the venturi powder pump means to an electrostatic powder spraying apparatus.