Method and apparatus for spray coating a workpiece

US6090450A · kind A · utility

Assignee

• LacTec GmbH Gesellschaft fuer moderne Lackiertechnik · DE

Inventors

• Ralf Kahmann · Heusenstamm, DE
• Udo Klein · Dietzenbach, DE
• Winfried Ott · Rodgau, DE
• Volker Weiss · Langenfeld, DE

Key dates

• Filing date: Feb 4, 1999
• Grant date: Jul 18, 2000
• Expiry date: Feb 4, 2019

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B05B12/1481
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

An apparatus and method for painting a workpiece while switching paint colors between successive painting cycles includes a paint supply switching device, a paint feed line connected to the paint supply switching device, a separating element adapted to move back and forth in at least a portion of the paint feed line, first and second receiver stations adapted to receive the separating element at the end positions of its travel in the paint feed line, and a paint spray nozzle at a terminal end of the paint feed line. The separating element is actively held in the first receiver station while paint of a first color is supplied through the paint feed line and sprayed from the nozzle onto a workpiece. To switch to a paint of a second color, the supply of the first paint is terminated, the separating element is released from the first receiver station, and a pushing medium pushes the separating element through the paint feed line, while residual paint is pushed from the paint feed line out through the spray nozzle. The separating element forms a sealing barrier between the pushing medium and the residual paint. Sensors detect the arrival of the separating element in the second receiver …