Electrostatic spray nozzle assembly

Patent metadata

Field	Value
Publication number	US-9962720-B2
Application number	US-201415023241-A
Country	US
Kind code	B2
Filing date	Sep 22, 2014
Priority date	Sep 20, 2013
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

An air assisted electrostatic liquid spray nozzle assembly having a relatively long elongated nozzle body with a spray tip and surrounding air cap disposed at a downstream end of the nozzle body. The spray nozzle assembly includes an upstream electrode for connection to a high voltage electric source, an elongated feed tube, an electrically enhancing stinger, and the spray tip which are secured and retained by the air cap in electrically conductive relation to each other such that liquid passing through liquid passages of the electrode, feed tube, stinger, and spray tip is discharged in an electrostatically charged pattern of liquid particles. The air cap is removable to permit easy removal and replacement of the spray tip, stinger, and liquid feed tube.

First claim

The invention claimed is:

1. An electrostatic spray nozzle assembly comprising:
an input head made of a non-electrically conductive material,
an elongated hollow nozzle body having an upstream end supported by said input head made of a non-electrically conductive material,
said input head having a liquid inlet for coupling to a liquid supply,
an electrode supported within said input head for connection to a high voltage electrical source,
said electrode having a liquid passage communicating with said liquid inlet,
an elongated feed tube disposed within said elongated nozzle body having an upstream end in electrically conductive contacting relation to said electrode and having a liquid passage communicating with said electrode liquid passage,
said feed tube and elongated nozzle body defining an air flow passage having a pressurized air inlet for coupling to a pressurized air source,
a spray tip at a downstream end of said nozzle body in electrically conductive contacting relation to a downstream end of said elongated feed tube and having a liquid passage in communication with said feed tube liquid passage and a discharge orifice for discharging liquid from the spray nozzle assembly,
said spray tip, liquid feed tube, and electrode being positioned in electrically conductive relation to each other such that upon coupling of said electrode to the high voltage electrical source, liquid passing through said liquid passages of said electrode, feed tube, and spray tip is electrically charged for discharge from said spray tip in a pattern of electrostatically charged liquid particles,
an air cap secured to a downstream end of said elongated nozzle body, and
said air cap defining an air flow passage about said spray tip in communication with said air passage defined by said feed tube and nozzle body and having an air discharge orifice from which pressurized air is directed about said pattern of electrostatically charged liquid particles discharging from said spray tip.

2. The electrostatic spay nozzle assembly of claim 1 in which said air cap is removably secured to said nozzle body such that upon removal of said air cap, said spray tip and feed tube are removable from the nozzle body from said downstream end thereof.

3. The electrostatic spay nozzle assembly of claim 1 in which said nozzle body has an elongated length of at least ten times its diameter.

4. The electrostatic spay nozzle assembly of claim 1 in which said nozzle body has an elongated length of at least twelve inches.

5. The electrostatic spay nozzle assembly of claim 1 in which said pressurized air inlet communicates through said input head with said air flow passage defined by said feed tube and said nozzle body.

6. The electrostatic spay nozzle assembly of claim 1 in which said electrode is supported within said input head with the liquid passage thereof in axial alignment with the feed tube liquid passage, said liquid inlet communicating with said electrode liquid passage through a side thereof.

7. The electrostatic spay nozzle assembly of claim 1 in which said feed tube extends beyond an upstream end of said nozzle body into a receptacle of said electrode in electrically conducting relation therewith.

8. The electrostatic spay nozzle assembly of claim 1 in which said liquid feed tube and elongated nozzle body define an annular air passage about the feed.

9. An electrostatic spray nozzle assembly comprising:
an input head made of non-electrically conductive material
an elongated hollow nozzle body supported by said input head made of a non-electrically conductive material,
said input head having a liquid inlet for coupling to a liquid supply,
an electrode supported within said input head for connection to a high voltage electrical source,
said electrode having a liquid passage communicating with said liquid inlet,
an elongated feed tube disposed within said elongated nozzle body having a liquid passage communicating with said electrode liquid passage,
said feed tube and elongated nozzle body defining an air flow passage having a pressurized air inlet for coupling to a pressurized air source,
a spray tip at a downstream end of said nozzle body having a liquid passage in communication with said feed tube liquid passage and a discharge orifice for discharging liquid from the spray nozzle assembly,
said spray tip, liquid feed tube, and electrode being positioned in electrically conductive relation to each other such that upon coupling of said electrode to an high voltage electrical supply source, liquid passing through said liquid passage of said electrode, feed tube, and spray tip is electrically charged for discharge from said spray tip in a pattern of electrostatically charged liquid particles
a stinger disposed within said spray tip in interposed electrically conductive relation between said spray tip and feed tube, said stinger having a liquid passage communicating between said feed tube and spray tip liquid passages, and said stinger having a downstream electrode pin positioned concentrically within said spray tip passage and protruding outwardly of said spray tip discharge orifice for enhancing electrostatic charging of liquid discharging from the spray tip, and
an air cap secured to said downstream end of said elongated nozzle body for securing and retaining said spray tip, liquid feed tube, and electrode in electrically conductive relation to each other, and
said air cap defining an air flow passage about said spray tip in communication with said air passage defined by said feed tube and nozzle body and having an air discharge orifice from which pressurized air is directed about said pattern of electrostatically charged liquid particles discharging from said spray tip.

10. The electrostatic spay nozzle assembly of claim 9 in which said spray tip has an upstream cylindrical section, an inwardly tapered intermediate conical section, and a downstream cylindrical nose portion which defines said spray tip discharge orifice, and said stinger has an upstream cylindrical portion concentrically disposed within the cylindrical upstream section of said spray tip, a conical intermediate section seated in electrically conductive relation to the conical spray tip section, and a downstream electrode pin concentrically disposed within said spray tip nose portion and extending downstream thereof.

11. The electrostatic spay nozzle assembly of claim 10 which said stinger is formed with a plurality of liquid flow passages communicating between said feed tube and spray tip liquid passages.

12. The electrostatic spay nozzle assembly of claim 11 in which said spray tip has an outwardly extending retention flange interposed between said downstream end of said nozzle body and said air cap, and said retention flange being formed with a plurality of air passages for communicating pressurized air between said airflow passage defined between said feed tube and nozzle body and the air cap defined air flow passage.

13. An electrostatic spray nozzle assembly comprising:
an input head made of non-electrically conductive material,
an elongated hollow nozzle body supported by said input head made of a non-electrically conductive material,
said input head having a liquid inlet for coupling to a liquid supply,
an electrode supported within said head for connection to a high voltage electrical source,
said electrode having a liquid passage communicating with said liquid inlet,
an elongated feed disposed within said elongated nozzle body having an elongated liquid passage communicating with said electrode liquid passage,
said feed tube and elongated nozzle body defining an elongated air flow pas

Assignees

• Spraying Systems Co

Inventors

• St Peter Glenn R
• Leone John
• Zaverson Charles J
• Ackerman Thomas E

Classifications

• B05B7/067

  the liquid outlet being annular · CPC title

• B05B5/03 Primary

  characterised by the use of gas {, e.g. electrostatically assisted pneumatic spraying (B05B5/04, B05B5/043, B05B5/047 take precedence)} · CPC title

• B05B5/1608

  the liquid or other fluent material being electrically conductive · CPC title

• B05B5/0533

  Electrodes specially adapted therefor; Arrangements of electrodes · CPC title

• B05B5/043

  using induction-charging · CPC title