| 摘要 |
1,244,106. Space vehicles. WESTING- HOUSE ELECTRIC CORP. 7 Feb., 1969 [16 Feb., 1968], No. 6757/69. Heading B7W. [Also in Divisions F2 and H4] A self-erecting, thin wall, hollow boom 15, which can be extended for a considerable length without bending, e.g. as an aerial or for gravity-gradient stabilization in space, has a separable seam 29 with interengaged abutting edges biased together in extension helically around, and along, the boom, the latter being formed from an unrolled, notched edge spring strip 16 which is curled transversely into selfbiased interengaged abutment at its edges to form the seam 29. As shown, the strip 16, made, e.g. of beryllium copper, and stored on a reel 17, has notches 20 along its longitudinal edges to define tabs 19, 19 which overlap to form the helical seam 29 when the strip is unrolled to erect the boom, every other tab 19 on each, edge preferably having its leading edge bent inwardly to slide beneath an opposite non-bent tab. The seam 29 is produced by advancing one edge of the strip relative to the other as the strip unwinds from the reel 17, small degrees of offset being accomplished by passing the strip over a guide 34, and larger amounts, by prestressing the strip accordingly. The strip may have one edge advanced so that a tab (19a, 24a) on the edge engages an advanced tab (19b, 25b) of the other strip edge, Fig. 3, not shown. |
