Flat roof solar sensor structures and bolt attachment

A solar panel attachment assembly for use in affixing solar panels to flat roof structures comprising:

• an elongated purlin including a strip of sheet metal longitudinally bent into an elongated sideways oriented U-shaped channel with an upright wall, a mounting wall integrally attached to the lower edge of the upright wall, and a horizontal cross piece integrally attached to the upper edge of the upright wall, the purlin includes one or more vertically upwardly extending solar panel positioning elements integrally formed in the cross piece approximately midway between the edges and separating the cross piece into two parallel longitudinal horizontal support surfaces, the upright wall, the mounting wall, and the cross piece extending longitudinally the entire length of the purlin;
• a solar panel having a generally rectangular shape and including a rectangular metal frame with a generally L-shaped cross-section, a lower horizontal wall of the L-shaped cross-section forming a mounting surface and a vertical wall forming an outer surface of the solar panel, an inwardly directed channel formed on the upper edge of the vertical wall to surround and fixedly engage outer edges of solar sensors;
• a plurality of attachment bolts, each bolt including a head including structure for attaching a driving tool to the head and an elongated body integrally attached to the head and extending perpendicularly outwardly from the head to an end, a portion of the body extending from the head to a midpoint threaded with bolt threads and a portion of the body extending from the midpoint to the end formed into a drill bit, the drill bit having an outer diameter smaller than the outer diameter of the bolt threads;
• the plurality of attachment bolts being positioned to extend through the cross piece of the purlin and through a hole formed by the drill bit in the lower horizontal wall of the L-shaped cross-section;
• and
• a plurality of internally threaded lock washer/nuts positioned in engagement, one each, with the attachment bolts on the upper surface of lower horizontal wall of the solar panel to hold the solar panel in tight abutting engagement with the purlin.