A modular color changer provides selected paint colors for spraying and recirculates nonselected colors. A module is provided for each paint color to be selected, and each module has an inlet for connection with a respective supply of paint, a recirculate outlet, a delivery outlet and a single valve...http://www.google.es/patents/US4846226?utm_source=gb-gplus-sharePatente US4846226 - Color changer
