Process for coating wire with insulation

US4329377A · kind A · utility

Assignee

• Felten & Guilleaume Carlswerk Aktiengesellschaft · DE

Inventors

• Wolfgang Voelker · Naumburg, DE
• Alfons Schmitt
• Fritz Radeck · Naumburg, DE

Key dates

• Filing date: Jul 10, 1980
• Grant date: May 11, 1982
• Expiry date: Jul 10, 2000

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B05D2401/32
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Wire is coated with an insulator in an electrostatic coating machine which establishes a potential difference between the wire and the insulation and thereby causes the insulation to adhere to the wire electrostatically, without the use of solvents. After such coating, the coated wire is sintered and hardened in order to form a lacquered wire with a uniform insulation thickness. Insulation thickness can be maintained at a desired value by adjusting the length of wire being exposed to the insulator in pulverized form within the electrostatic coating machine and/or the potential difference therein. The supply of insulator used in pulverized form is continuously fed into the electrostatic coating machine so as to prevent smaller and lighter particles from being first attracted to the wire, and thereby depleting such particles excessively while leaving only larger and heavier particles available for coating. The final thickness of the insulation is constantly kept within a predetermined tolerance by varying the rate of feed of insulator supply to the coating machine directly as a function of insulation thickness, which insulation thickness is continuously monitored.