Powder transport method & apparatus
AssigneeHaden Schweitzer Corporation
InventorsJeffrey C. Johnson, Jeffrey R. Joyce
Life of this patent
Estimating the term…
Abstract
The present invention is directed to a powder paint delivery method and apparatus employing a pressurized reservoir pump that supplies a controlled stream of densely fluidized or dense phase powder paint to the applicator though a powder delivery conduit. The powder flow rate is a function of the pressure in the reservoir and the flow resistance from the reservoir to the applicator, and is therefore very stable over time, and simple to control. The powder flow can be controlled by holding the resistance of the powder flow path constant and varying the pressure in the reservoir, or by holding the reservoir pressure constant and varying the resistance of the powder flow path.
Claims14
A method for transporting paint powder to a paint applicator comprising:
- providing a volume of paint powder housed in a receptacle;
- maintaining the receptacle at an elevated pressure;
- fluidizing the paint powder within the receptacle;
- transporting the paint powder in a dense phase from the receptacle to the applicator through a delivery conduit, said conduit having a powder pick-up end positioned within the volume of fluidized paint powder in the receptacle and a delivery end in communication with the applicator;
- and
- controlling the pressure in the receptacle and/or the paint powder flow path resistance to thereby achieve a predetermined paint powder flow rate to the applicator.
A powder pump apparatus for transporting powder to a powder coating applicator, comprising;
- a vessel suitable for pressurization and having an air-permeable wall that defines a powder reservoir in the vessel above the wall and a fluidizing air plenum below the wall;
- a first controlled source of pressurized air in communication with the plenum to both fluidize the powder contained in the reservoir and pressurize the reservoir;
- said vessel also having an inlet for loading powder into the reservoir and a restricted outlet to allow air to be exhausted from the reservoir while providing sufficient airflow resistance for pressurization of the reservoir;
- and
- a powder delivery conduit having a powder pickup end positioned within the fluidized powder in the reservoir and a delivery end in communication with the applicator.
Dependencies are inferred from the claim text.