Self-adjusting power supply for induction charging electrodes
US4073002A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1976 |
| Grant date | Feb 7, 1978 |
| Priority date | — |
| Expiry date | Nov 2, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/53
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A self adjusting power supply for induction charging electrodes used in electrostatic spray coating apparatus is disclosed. A first resistance of high ohmic value is connected in series between a source of high direct current voltage and the induction charging electrode, while a second resistance is connected between the source of voltage and a ground reference point. The first resistance acts as a voltage divider with the spacial impedance which exists between the charging electrodes and ground in the spray nozzle of the spray coating apparatus, and serves to regulate the charging voltage and to compensate for variations in the conductivity of the material being sprayed. If the value of the spacial impedance should decrease for any reason, the increased current flow therethrough produces an increase in the voltage drop across the first resistance, thereby reducing and thus regulating the potential at the charging electrodes and serving to prevent corona and arcing within the spray gun. The ohmic value of the first resistance, which is in the range of 1-50 gigohms, is sufficiently high to prevent any substantial current flow from the charging electrode, thereby reducing the shock h…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.