| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a press forming machine for manufacturing the mirror finished surface for a parabolic antenna by which the possibility of the generation of cracks from joined parts during working is eliminated, the very high accuracy of the mirror finished surface is obtained, also the fraction defective of the mirror finished surface due to the cracks is reduced and the reduction of the cost of equipment is enabled. SOLUTION: By joining a plurality of aluminum plates by a friction stir welding method, a planar plate 48 for mirror finished surfaces is manufactured. Next, after setting the planar plate 48 for mirror finished surfaces on the ring-shaped mount 51 of the press forming machine 50, by lowering cylinders 23 for elevating and lowering an outer periphery press and pressing the outer peripheral part of the planar plate 48 for mirror finished surfaces against a curl forming groove 52 of the ring-shaped mount 51, a curl is formed and the planar plate 48 for mirror finished surfaces is fixed to the ring-shaped mount 51. Next, by lowering cylinders 22 for elevating and lowering the upper die and forming the planar plate 48 for mirror finished surfaces into a paraboloidal shape with the upper die 24, the mirror finished surface plate for parabolic antennas is manufactured. |
