GB1042179A - Improvements in television cameras - Google Patents

Abstract

1,042,179. Television; cathode-ray tube accessories. COMPAGNIE FRANCAISE THOMSON-HOUSTON. Sept. 20, 1963 [Sept. 21, 1962], No. 37102/63. Headings H4F and H4T. [Also in Division G6] A television camera tube, particularly for use in an atomic reactor, is cooled by the expansion of a liquid coolant contained in a double-walled housing surrounding the tube. In one embodiment, Fig. 1, the camera tube 1 together with its associated amplifier 2, lens 8 and a connection assembly 3 are contained in a metal tube 22 sealed at one end by a connector 4 and at the other end by a quartz plate 9. The tube is provided with interlocking means including a screw 17 for retaining it inside a double walled housing 13 (into which it may be readily inserted) the space 12 between the walls being evacuated and the interior 11 containing the liquid coolant introduced by means of a valve 16 and which on expansion escapes through a valve 15. When the camera is employed for examining the interior of gascooled atomic reactors the liquid coolant used is preferably of the same nature, CO 2 being utilized in the present invention. In the case of examining a (vertical) fuel element sheath, such as 19, the assembly of camera tube &c. and cooling housing is lowered into the sheath under its own weight by means of the electrical connection cable 5, stainless steel guide springs 7 (or rollers) being provided to allow of accurate focusing over the entire length of the sheath. To enable the camera to " view " the side wall of the sheath the latter is illuminated by lamps 10 and image light is directed into the camera by means of a conical reflector 6. In a second embodiment (Fig. 2, not shown) in which the sheath is also illuminated by lamps 10 image light is directed into the camera by means of a 45 degrees mirror 6 which may be rotated about the camera tube axis by means of a turbine 23 driven by the reactor coolant gas, the mirror being stopped in a desired position by means of an electromagnetic brake 25. For focusing purposes a pinion 29 driven by a step-by-step motor and meshing with a gear 35 rotates lens 8 and this rotation is converted into an up-down translatory motion by means of a pin 34 engaging a curved groove 33 in the lens housing. In this embodiment the cooling housing is provided with an annular space 30 in which the coolant fluid (liquid CO 2 ) expands and evaporates the fluid entering via a tube 31 and emerging via a tube 32 which communicates with the outside through a valve such as 15 (Fig. 1).