GB438892A - Improvements in or relating to apparatus for grading materials - Google Patents

Abstract

438,892. Sifting - apparatus. WETTLAUFER, W. L., 40, Pearl Street, Buffalo, New York, U.S.A. May 22, 1934, No. 15253. [Class 117] One or more flat sieves 16 is or are mounted in a frame 22 which is sup ported for rotary movement, and in cludes devices for imparting to the sieves a vibratory movement, the axis of rotation being perpendicular to the sieve surface anc adjustably inclined As shown, the sieve: are clamped between two cross-heads 19 20, resiliently sup ported between springs 35 and 45 which are adjustable by a screw 37 pass ing through an ad justablecross-bar 38 The base 23 of the frame is annular and is supported by grooved pulleys 25 on the casing of a motor 27 which is pivotally supported on the base structure 34. The motorshaft 30 carries a block 51 in which are slidably mounted under spring pressure a number of plungers 54, preferably of oil soaked wood, bearing on ratchet projections 58 on the cross-head 19 for imparting the vibratory motion to the sieves. The rotary movement is imparted to the screen by a pulley 69 mounted on the frame and driven by a belt 67 from a counter-shaft which in turn is driven by a belt 62 from a pulley on the motor shaft. The pulley 69 is normally loose and is connected to the frame 23 by a hinged latch coacting with a pin thereon. Intermittentmotion is obtained by a ramp which is provided to lift the latch at regular intervals.