| 摘要 |
1,049,457. Travelling wave tubes. INTERNATIONAL STANDARD ELECTRIC CORPORATION. July 6, 1965 [July 7, 1964], No. 28533/65. Heading H1D. A travelling wave tube helix assembly comprises three equally angularly spaced dielectric support rods disposed within a tubular metallic envelope and engaging three longitudinal grooves formed on the inner periphery of the envelope, and a resilient helix structure which applies pressure to secure the rods in the grooves. A signal attenuating coating, e.g. carbon, is formed on the rods, the coating being divided into two isolated longitudinal portions, one portion being in contact with the helix the other in contact with the metallic envelope by forming two diametrically opposed flats along opposite sides of the rods. In a method of assembly, the helix is wound about a shaft by rotating one end of the helix, the other end being fixed, thus reducing the diameter of the helix, and the assembly is inserted within the envelope with the rods; upon release of the helix it expands and forces the rods into engagement with the grooves. |
