Voltage block for electrostatic spraying apparatus
US5518186A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 8, 1995 |
| Grant date | May 21, 1996 |
| Priority date | — |
| Expiry date | May 8, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05B5/1616
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A voltage block device for use with electrostatic spraying apparatus for conductive coatings is disclosed. The device maintains an air gap which electrically isolates a grounded paint supply from a charged spray head to prevent the leakage of potential to the grounded paint supply. The device comprises a tube made of non-conductive material and having ends which are closed by upper and lower caps to define a closed space which is pressurized. A valve secured in the upper cap delivers paint into the closed space to raise the level of conductive coating material therein to the level of an external sensor. In a first mode of operation, valve interlock circuitry opens the valve when the spray head is not charged and the sensor detects a low level of coating material. The valve closes if the level of conductive coating material in the closed space reaches the external sensor or the spray head becomes charged, restoring an air gap which electrically isolates the grounded paint supply. In a second mode of operation, the valve interlock circuitry includes a timer and opens and closes the valve intermittently, when needed, so it dispenses discreet bodies of conductive coating material separ…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.