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US 4,182,490 AGranted
Electrostatic spray gun
AssigneeNordson Corporation
InventorJames L. Kennon
Life of this patent
Estimating the term…
Abstract
An electrostatic spray gun is disclosed which comprises a high valued resistance in the barrel portion of the gun, and a second resistor in the nozzle of the gun closely adjacent to a charging electrode projecting from the nozzle to provide safer operation.
Claims22
An electrostatic coating apparatus comprising:
- a nozzle portion made from substantially nonconductive material, having a fluid discharge opening and effective to project a dispersed cloud of coating material therefrom;
- a small electrode extending from said nozzle portion;
- a coating material conduit in communication with said fluid discharge opening;
- a high voltage electrical path passing through the nozzle portion and adapted to connect said electrode to a source of high voltage electrical power;
- and
- at least a first series resistor in said electrical path located in said nozzle portion said first series resistor being in at least the megohm range.
3 more elements
An electrostatic coating apparatus comprising:
- a barrel portion having a fluid conduit and a high voltage electrical path therein, one end of said fluid conduit being adapted to be connected to a source of fluid under pressure, and wherein one end of said electrical path is adapted to be connected to a source of high voltage electrical power and wherein a second end of said electrical path in said barrel is adapted to be connected to another electrical path;
- a substantially non-conductive nozzle connected to said barrel and having a fluid conduit and high voltage electrical path therein and a thin electrode extending therefrom, said fluid conduit in said nozzle being in communication with said fluid conduit in said barrel and said electrical path in said nozzle having a first end connected to said electrode and a second end connected to said second end of said electrical path in said barrel, said electrical path in said nozzle comprising at least a first series resistor in the megohm range connected to said electrode.
An electrostatic spray coating apparatus comprising:
- a barrel portion having:
- a fluid conduit therein adapted to have one end connected to a source of fluid under pressure;
- and a first resistor in the megohm range in said barrel and having a first and second end, said first end being adapted to be connected to a source of high voltage electrical power;
- a removable air atomizing nozzle attached to said barrel portion and made from substantially non-conductive material, and having:
- a fluid discharge orifice;
- a fluid conduit in fluid communication with said orifice and with the fluid conduit in the barrel portion;
- and a thin electrode extending from said nozzle;
- and
- a second resistor located in said nozzle with one end connected to said electrode and the other end electrically connected to the second end of said first resistor.
6 more elements
A method of electrostatic spray coating comprising the steps of:
- dispensing a disperse coating material toward an object to be coated from a substantially electrically nonconductive nozzle;
- imparting an electrical charge to said coating material by means of a small electrode extending from the nozzle;
- supplying high voltage electrical power from an electrical power source to said electrode, sufficient to impart said charge to said coating material;
- dissipating electrical energy supplied to said electrode through at least a first resistor in the megohm range located in said nozzle.
1 more element
A method of electrostatic spray coating comprising the steps of:
- dispensing a disperse cloud of coating material toward an object to be coated from a substantially electrically non-conductive nozzle;
- imparting an electrical charge to said coating material by means of a small electrode extending from the nozzle;
- supplying high voltage electrical power to said electrode from an electrical power source sufficient to impart said charge on said coating material, through at least a first resistor in at least the megohm range located in said nozzle.
Dependencies are inferred from the claim text.