| 摘要 |
<p>PURPOSE:To provide a highly strong and light seat frame having a window in the central portion of its bottom plate in high yield by a method wherein fiber-reinforced thermoplastic synthetic resin strips are hated, placed in the shape of # on a - shaped projection of a male die, and formed. CONSTITUTION:A resin strip 20 is formed of a fiber-reinforced thermoplastic synthetic resin in which long glass fibers are embedded along the longitudinal direction. The strip 20 is provided with roughly the same width as a die face 14 of a male die 11 and with a length sufficient for it to extend along one side of the die face 14 so that its end portions extend along die faces 15 to the proximity of a die face 16. The required amount is determined according to the thickness so that the material may be properly distributed over the whole of a frame upon drawing forming. With dies 11 and 12 heated to 40-60 deg.C, the strips 20 are heated to 180-250 deg.C and placed in the shape of a # on the die face 14 of the die 11 as indicated by chain lines. With the die 12 fitted on and pressed against the die 11, the resin flows as indicated by arrows a, and the strips 20 are drawn to form a seat frame.</p> |
