| 摘要 |
561,505. Composite metal sectionbars. MILLS SCAFFOLD CO., Ltd., and WELLS, G. W. Aug. 18, 1942, No. 11570. [Class 20 (ii)] Composite sectionbars formed by assembling and securing together angle or channel-section pressed sheet-metal sections have the flanges formed of double thickness metal by turning the edges of the flanges inwardly to extend to the web. For an H or I-section bar, two sheet-metal channel-bars 3, 4 are joined back to back, and the flanges 3b, 4b are made sufficiently long to be turned back upon themselves with the ends 3c, 4c turned again along the webs of the elements or back again upon themselves. For a T-section composite bar sheet-metal angle-bars 5, 6 are joined by two flanges while the other flanges 5b, 6b are turned back upon themselves as shown at 5c, 6c. The pressed-metal parts may be joined together in any suitable manner and the turned-back portions may be spot-welded to each other and to the webs. |
