| 摘要 |
<p>PURPOSE: To join a small crosspiece to a crosspiece by press-fitting the small crosspiece in a cutout groove formed in a rise-up fin of the crosspiece. CONSTITUTION: Cutout grooves 11 in rise-up fins 10 are inclined in opposite directions so that connecting walls 22 in joint beads 20 of a small crosspiece 2 are breakable. Thus, when the small crosspiece 2 is press-fitted, the connecting walls 22 are partly broken by inclined cutout end edges 13. These are received in front end curved parts 12 of the cutout grooves 11, and opposite wall parts at the front ends of the joint beads 20 bridges between remaining rise-up parts 14 left in the rise-up fins 10 so that the small crosspiece 2 is joined by clamping the edge parts of the cut-out grooves with the opposite walls 21 of the joint beads 20 and by clamping of the remaining rise-up parts 14 in a close-fit condition.</p> |
