Solar liquid heating system

In a solar energy collector having a frame, heat insulation means mounted thereon and forming the bottom, sides and ends of a chamber, cover means on said frame over the chamber of a material permitting solar energy to pass therethrough and into the chamber, solar energy collecting means mounted on the frame and located in the chamber to absorb energy for the sun and transmit heat energy to a liquid wherein the collecting means includes a plurality of plates disposed in side-by-side relation wherein said plates are similar and include respectively complementary laterally adjacent edges, a plurality of tubes mounted in engagement with the plates at their respective edges, and tubular inlet and outlet manifolds connected to the tubes for liquid flow therethrough for solar heating,

• the improvement comprising, each said plate having an extended planar central body between lateral edges thereof,
• one said lateral edge defining a first arcuate section disposed entirely on one side of said plate extending from a juncture with said central body and terminating in a planar flange which is substantially planar with said central body, and a hook extending from the other side of said plate and terminating in a laterally directed lip extending obliquely toward the concave face of said arcuate section,
• the other said lateral edge of said central body defining a substantially planar offset step on the opposite side of said plate from said first arcuate section, said planar step merging into a second arcuate section disposed entirely on said other side of the plate and terminating in a hook substantially coplanar with said offset portion, said hook havng a lip extending obliquely outwardly from said plate,
• said plate including said body portion, said arcuate sections, and said step comprising thin sheet material of substantially uniform thickness,
• each said tube is received in one of said arcuate sections wherein said oblique hooks permit swinging movement of a complementary arcuate section of another said plate into overlying relation with said tube to substantially entirely enclose the same within said thin walls of the plates, thereby to maximize heat transfer between said thin plates and said tubes, said arcuate section of adjacent plates surrounding said tube and so disposed so as to locate the tube in an outwardly extending position with respect to each side of said plate thereby to further maximize heat transfer,
• and means securing said terminal flange on one plate to said step section on said other plate.