PURPOSE: To obtain the frame to be light in weight and to improve the production efficiency by using an Al extruded shape, forming excision parts for forming openings of the shape and a number of staggered slots, then performing a stretch working.
CONSTITUTION: The extruded shape made of an Al alloy 1 having hollow upper and lower frame bars 14, 15, 17, 18, side walls 12, 13 and upper and lower face walls 11, 16 are previously manufactured. Then, for the shape 1 of prescribed length, the prescribed positions of each face wall is cut off ranging a required length to form the excision part 2. On each face wall except the excision part 2, the slots 3 are punching formed staggeringly, the stretch work is performed on the excision part 2 and slots 3. Each frame bar 14, 15, 17, 18 is bent to form expanded openings 21, 22, and the frame A is completed. Because using the Al material, the frame A is manufactured in a short time without performing welding, the frame is made light in weight and the production efficiency is improved.
TSUKUDA ICHIZO
ONEDA NOBORU
SUKIMOTO KISHIN
| JPS5394253A | 1978-08-18 | |||
| JPS52125457A | 1977-10-21 | |||
| JPS62137128A | 1987-06-20 |