GB412837A - Improvements in electric discharge tubes - Google Patents

Abstract

412,837. Discharge apparatus. MULLER AKT.-GES., C. H. F., 24, Rontgenstrasse, Hamburg, Germany. Nov. 15, 1933, No. 31872. Convention date, Dec. 2, 1932. [Class 39 (i).] In a high tension device, particularly an X-ray tube, in which two re-entrant portions, forming tubes of insulating material, each carrying an electrode, are arranged parallel with the axis of the device and extend into the device from one end, the supply conductors are led into the tubes and insulating sheaths surrounding the conductors also extend into the tubes. In one form, Fig. 1, an X-ray tube comprises a metal head 1 and a glass portion 2 con. taining re-entrant tubes 3, 4. The anode 5 and cathode 6 are mounted on these tubes. An insulating tube 13 with a metal lining 14 surrounds the cathode leads. On the anode side, an insulating tube 15 surrounds concentric metal tubes 16, 17 which deliver a cooling fluid to the anode 5. The insulating tubes 13, 15 are associated with the cable coverings 9, 10. The cables are also provided with a metal cover connected to a metal envelope 18 inside which an insulating member 19 surrounds the tube. The envelope 18 may be replaced by a metal coating on the envelope 19. The envelope 18 is provided with a spherical head 21 whose centre lies at the focal spot. A lead layer 20 is inserted between the head 1 and the insulator 19. The anode mirror is so arranged that a perpendicular to it forms equal angles with the tube axis, the axis of the cathode ray beam in the plane of the drawing and the normal to the plane of the drawing. In consequence, two beams of X-rays emerge, one axial to the device and the other normal to the first. Windows, one of which is shown at 8 are provided for these beams. The re-entrant parts may be filled with a material such as compressed air, oil or a solid cast material, resistant to breakdowns. The front of the head 1 may be shaped as a hemisphere, the centre of which lies in the focal point of the tube. The rays may emerge through a window shaped as a slit with rounded corners, giving a fan-shaped beam.