| 摘要 |
<p>The solar heater box is prefabricated from sheet metal with separate sides and interlocking base. The two longer sides (1, 2) are folded to a straight vertical section (6) with a bottom channel (7) on the inner face and the top is folded at 90 deg. to form a flange (8), having another channel (9) opposite the lower. Tongues on each long side lock into channels on the similarly folded shorter sides. A tongue on each longer side flange clears a similar tongue on the shorter side and slides between the faces. The flat base (5) has folded down sides (20, 21) locking in the bottom channels (7).</p> |
