GB436745A - Improvements in x-ray apparatus - Google Patents

Abstract

436,745. R÷ntgen - ray apparatus. BURDEN, W. M., PULLIN, V. E., and GREATBATCH, A. R., Royal Arsenal, Woolwich, London. May 15, 1934, No. 14642. [Class 98 (i)] Apparatus for examining specimens of material such as engineering castings comprises a box provided with a movable member whereby the specimen is moved into or out of the box, and such that when the member moves the specimen into the box the radiation can penetrate into the box but is prevented from emerging therefrom, while when the member moves the specimen out of the box, the radiation is prevented from entering the box. As shown, the box comprises chambers b, c, carried on a wheeled support d which may be run into position over a ray-tube a. The chamber b is open at one end and is fitted with a slidable tray having a front wall adapted to close the open end and a base comprising a ray-permeable part e as of aluminium and a ray-impermeable part e<1> as of lead. The box is slotted to allow the rear part of the tray to emerge when the tray is pushed in. To insert a specimen, the tray is drawn out into the position shown, in which the impermeable part e<1> cuts off the radiation from the chamber, and the specimen is placed on the permeable part e. When the tray is pushed in, the specimen on the part e rests above the emission window of the ray-tube a, which may be fitted with a variable diaphragm operated by a handle m. At g in the chamber b is a fluorescent screen, which may be manipulated by a handle h ; the screen may be replaced or supplemented by a photographic plate. The chamber c contains an inclined mirror reflecting the screen-image into an eyepiece k. The front of the box is wholly covered by a sheet of lead, which also extends down below the base to screen the ray-tube. The other surface to the box are also lead-covered, and the eyepiece k is backed with a lead-glass filter. The chamber band tray may be illuminated by a low-power electric lamp.