Patent · US Expired

Electrostatic spray gun

US5044564A · kind A · utility

58Cited by
24References
41Claims
0Family size

Inventor

Key dates

Filing dateNov 21, 1989
Grant dateSep 3, 1991
Priority date
Expiry dateNov 21, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB05B5/0533
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An adapter for converting spray guns to electrostatic or induction charging includes a housing mountable on a spray gun. A high voltage power source is contained in the housing and is connected to an electrode assembly mounted on the front of the housing. The electrode assembly includes four electrodes which extend in front of the spray gun nozzle and air cap and are spaced symmetrically around the spray axis. The nozzle is electrically grounded, while the electrodes carry a voltage in the range of 3-15 kV, to produce in the spray path from the nozzle an electrostatic field which produces electrical charges on the sprayed particles. When conductive liquids are sprayed, the particles are charged by induction at relatively low electrostatic field gradients, while nonconductive liquids require high electrostatic field gradients which produce corona effects. These corona effects are enhanced by the provision of a corona needle mounted on the nozzle at the spray axis.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.