GB813148A - Multiple source radio-active device - Google Patents

Abstract

813,148. Sources of radio active radiation. FOXBORO CO. Jan. 23, 1957 [Jan. 26, 1956], No. 2516/57. Class 98(1) In a container for two or more radio active sources of radiation, the sources are mounted in a cylindrical housing having at least one radiation-permeable window in its cylindrical wall, and means to rotate the sources about the housing axis to bring each source opposite a window from a shielded position, the sources following circular paths and always remaining in the housing. As shown in Fig. 5, a cylindrical shielding body 25 is formed with threaded bores 41 in which sources of radiation are adjustably mounted. The sources consist of threaded plugs 41<SP>1</SP> formed with chambers 48 which are filled either with a gas such as krypton 85 or a solid such as strontium 90 and closed by a window 49. The cylindrical body 25 is supported for rotation in a shielding cylinder 23 by a plug 24 ;at one end, having a boss 30 pivotally supporting one end of the body 25, and an end portion 31 rotatable within the cylinder 23 by means of a knurled knob 32. The rotation of the inner cylinder is limited by pin-and-slot means. A radiationpermeable window 27 (see also Fig. 6), is formed in the cylinder 23. The body 25 may be rotated between three positions in which a screw 40 engages with one of three recesses 36, 37, 38. In one position the sources are all clear of the window 27 in another position one of the sources is opposite the window; and in the third position two of the sources are opposite the window. The sources may be adjusted along their threaded bores by screw driver slots 41<SP>11</SP>, 42<SP>11</SP>, 43<SP>11</SP> accessible through holes 45, 46, 47 in the cylinder 23. The limitation of the turning movement of the body 25 is such that the sources can never be brought opposite the screw driver holes. In an alternative form, the main body 25 may be held stationary, the housing 23 rotating with respect thereto.