| 摘要 |
<p>A collector structure for a linear beam device is disclosed having a segmented ceramic collector core that permits sustained operation at high temperatures and high power densities, such as encountered in miniature traveling wave tubes. More particularly, the collector assembly (20) provides efficient heat transfer from the collector core at elevated temperatures while reducing stresses on collector components caused by thermal cycling. The collector assembly comprises a heat sink (40) having a cylindrical cavity (46) providing interior vacuum walls for the assembly (20), a segmented annular ceramic insulator (22) disposed inside the cylindrical cavity (46), and an electrode (25) disposed inside and against the ceramic insulator (22). The ceramic insulator (22) preferably comprises separate sectors separated from one another by gaps, and may be notched in its outer surface for high-voltage stand-off from the heat sink (40). The electrode is preferably not brazed or soldered to the ceramic insulator (22). A second stage (28) of the electrode (25) may be probeless and may comprise a central conical depression having a aspect ratio greater than one. In an embodiment of the invention, the heat sink and second stage electrode (28) of the collector assembly (20) are both made of molybdenum, and the ceramic insulator (22) is made of beryllium oxide, aluminum nitride, or alumina. In an alternative embodiment, the heat sink (40) and the second stage electrode (28) are both made of copper, and the ceramic insulator (22) is an aluminum nitride material.</p> |
