| 摘要 |
782,090. Making wave-guides; stamping. WESTERN ELECTRIC CO., Inc. March 16, 1956 [March 24, 1955], No. 8314/56. Classes 83 (2) and 83 (4). Apparatus for altering the shape of one end portion of a curved electromagnetic wave-guide of rectangular cross-section so that the end portion changes along its length into a circular cross-section includes a die having an L-shaped die cavity the leg of the cavity for receiving the said end portion having diverging flat side walls, a die plate covering the die cavity, a mandrel having a circular main portion and a forward portion which is tapered by providing converging opposite flat side walls on the mandrel and means for forcibly inserting the mandrel into the said end portion when the wave-guide is clamped in the die cavity. The apparatus comprises a base 16 supporting a die 21 having a cavity 26 consisting of a rectangular section 27 provided with a flared extremity 28 to accommodate wave-guides of different curvatures and a section 29 having opposite flat sides tapering from a small rectangular crosssection where it joins the section 27 to a larger semi-circular cross-section at the outer edge of the die. An upper die 31 is bolted to the die 21 and includes a removable insert 33 provided with a semi-circular aperture complementary to semi-circular section in the die 21. The dies are provided with inserts 37 having serrated faces for securely clamping the waveguide in the dies. The mandrel 38 is connected to a piston arm 39 and comprises a circular section 46 tapered as at 47 on opposite sides towards curved end links 58 and 51 which support the curved portion of the waveguide. In operation the inserts 37 are removed from the lower die 21 and a curved rectangular wave-guide is placed on the die cavity and all unoccupied space around the wave-guide is filled with a fusible alloy. The upper die is secured in position and the mandrel advanced to shape the wave-guide as shown in Figs. 9 and 10. |
