Solar trough mirror frame, rolling rib, roller, cleaning apparatus and method

A roller assembly engaging with a curved rib attached to a frame that holds mirrors of a solar parabolic trough system, the rib curving around an axis substantially parallel to the ground and comprises a profile with an I shaped cross section and is an I beam with flanges having a top portion that attaches to the frame, a central portion extending from the top portion and a bottom portion that engages with the roller assembly, the rib moving along the roller assembly as the frame moves, the roller assembly comprising:

• a housing which receives the bottom portion of the rib;
• a first roller disposed in the housing on which the rib moves when the frame moves;
• and
• a second roller disposed in the housing, the first roller disposed below the bottom portion of the rib and the second roller disposed above the bottom portion of the rib to constrain the rib from lifting out of the housing due to wind forces on the mirrors.

A support system for holding solar mirrors of a solar trough system comprising:

• a parabolic trough frame for supporting the mirrors which rotates about an axis substantially parallel to ground, the frame has a plurality of interconnected nodes, struts and chords supporting the mirrors from below the mirrors;
• a curved rib attached to the frame, curving around the axis substantially parallel to the ground, the curved rib having an axis, with the axis of the curved rib parallel to the axis of the parabolic trough frame, the rib is an aluminum extrusion;
• and
• at least a first roller having a curvature engaged with the rib along which the rib moves as the frame moves, the rib comprises a profile having a top portion that attaches to the frame, a central portion extending from the top portion and a bottom portion that engages with the first roller, the rib moving along the first roller as the frame rotates about the axis, the first roller comprises a housing which receives the rib, a roller disposed in the housing on which the rib moves when the frame moves, and the housing is an aluminum extrusion, the rib has a cross section that is I shaped and is an I beam with flanges, the rib is curved about the axis parallel to the I Beam flanges, substantially parallel to the ground, the roller is a bottom roller and including at least a first top roller disposed above the bottom portion of the rib, and the bottom roller disposed below the bottom portion of the rib.