GB189814971A - Improvements in or connected with Sifters for Flour and other Materials. - Google Patents

Abstract

14,971. Rainbow, F. J. G. July 7. Sifting flour &c.-Relates to sifting-machines for flour and other materials in which two or more sieves are arranged above one another, the mesh of a sieve being of increased fineness the lower its position in the series. Fig. 1 shows a form of the invention in which two sieves are operated by eccentrics. The sieves 1 and 2 are carried on rods 3 sliding in blocks 4 fixed to the framework. The sieves are worked by eccentrics 5 and 6 mounted on shafts 7 and 8 connected by a belt passing over pulleys 9 and 10 so that the speed of the lower shaft is greater than that of the upper shaft. The material to be sifted is placed in the hopper 12, at the bottom of which are transverse bars 13, or the bars may be arranged on the upper sieve. The material falling through the lower sieve passes away through the hopper 14. In some cases rubber buffers may be employed against which the rods 3 knock so as to agitate the material upon the sieve. An opening 22<a> is formed in the sieve through which the coarse material may pass and fall down a chute 23 or into a sack &c. A transverse strip 22 may also be provided. Modifications are described, in one of which cams are used to actuate the sieves, and in another studs secured to a disc serve for this purpose. The ratio of the speed of the sieves is adjusted according to the fineness of the meshes. The Provisional Specification states that a brush, working in suitable guides, may be used to clean the sieves.