FIELD: physics.
SUBSTANCE: cylindrical slit-type screen for gamma-ray probing radioactive ore has a screening tube filled with lead, a handle with straps, wherein the screening tube filled with lead completely encircles a cylindrical block for detecting gamma-rays which is divided into two equal parts which are hinged onto an axle and mounted on two bearing posts, and on the opposite side of the axle, parts of the screening tube, upon closure thereof, are such that the edge of one part with a shaped protrusion enters the shaped recess of the edge of the other part, the bearing posts are also tied by a protective plate lying over the slit formed upon rotation of parts of the screening tube and allow overlapping of slits between the rotating parts; on each part of the screening tube there are rigidly attached lugs which are hinged by a pull rod to the lower end of spring-loaded rods passing through bushings with outlet into a hollow handle; the rods are fixed on spring-loaded prongs which are pivotally connected to a board on the outer side of the handle; after reaching the top position, when the pulling board is moved by fingers of one hand upwards to the hollow handle, the rods turn an act on the pull rods and part of the screening tube and they open, and the detector begins to pick up gamma-rays "without the screen"; by pressing the board to the hollow handle, the fixing prongs are deflected and the rods, under the force of the springs, drop and parts of the screening tube close, thereby enabling to pick up gamma-rays "with the screen".
EFFECT: design of a screen which enables gamma-ray probing of walls and roofs of excavations without shifting the position of the screen at the measurement point so that the entire probing process is carried out using one hand.
4 dwg
