Apparatus and method for applying paint with roller coaters, preferably to photovoltaic panels

A roller coater for applying paint to mainly flat panels provided with different lengths comprised between a minimum and a maximum length workable by the roller coater, comprising, in a conveying direction of the panels:

• a feed roller covered by a first cover;
• an application head for applying the paint, the application head comprising an applying roller and a dosing roller, wherein the application head is covered by a second, vertical cover and a third, horizontal cover, the second, vertical cover and the third, horizontal cover being removable;
• a conveyor for the panels to be painted;
• rotation supports, on which ends of a shaft of the applying roller are rotatably mounted, the rotation supports being each adapted to be coupled and decoupled from a corresponding end of the shaft of the applying roller, a working position of the applying roller corresponding to a coupled condition of the ends of the shaft of the applying roller in the rotation supports, the rotation supports being configured to have a withdrawing position;
• guiding brackets defining L-shaped translation guides for withdrawing the applying roller, each of the L-shaped translation guides being defined by a substantially horizontal supporting surface and an upwardly extending tooth providing an end of stroke,
• wherein the L-shaped translation guides enable an initial translation of the applying roller along the substantially horizontal supporting surface for disengaging and distancing, in a radial direction, the ends of the shaft of the applying roller from the rotation supports and in a direction of the feed roller, and a successive translation in a lifting vertical direction from the end of stroke, distancing the applying roller from the conveyor;
• and
• a lifting organ of the applying roller,
• wherein an interaxial distance between the feed roller and the applying roller is at least, sufficient to enable a passage of the applying roller during removal, and
• shorter than the minimum length of the panels.