GB534047A - Improvements in and relating to cyclotrons - Google Patents

Abstract

534,047. Cyclotrons; electricity supply arrangements. AKT.-GES. BROWN, BOVERI, & CIE. Dec. 19, 1939, Nos. 32523, 32524 and 32525. Convention dates, Dec. 19, 1938, Dec. 29, 1938 and Dec. 31, 1938. [Class 39 (i)] In a cyclotron a high frequency transformation is effected within the cyclotron chamber so that the potential at the lead-in insulators is relatively low. A transformer with independent primary and secondary windings or an autotransformer c, Fig. 4, may be used ; or Lecher wires are arranged so that a voltage anode occurs at the insulators d and a loop at the accelerator electrodes b. The Lecher wires may connect to an auto-transformer whose midpoint is connected to the chamber a. A step-up of 30 to 1 is obtainable. Tuning of the h.f. supply can be effected by (i) variation, of the inductance of the transformer by metal insets e or (ii) by an adjustable plate or plates h, Fig. 5, for varying the capacity of the electrodes b; the adjustments are made by rods or a spindle through bellows g, the use of these internal adjusting means rendering unnecessary the large size switch means usually employed on the low tension supply side to the cyclotron. The auto transformer may be construlent of concentric piping c, d, Fig. 6, supplying cooling water to the electrodes b ; the lead-in conductors e, f consist of piping from which branches h, i are led to the pump and radiator, the pipes being intertwined to form chokes, or they are shortcircuited. In a modification these chokes are dispensed with, the mid point of the auto transformer being connected to the chamber a, and the pipes e, f forming part of Lecher supply wires.