GB920973A - Milling apparatus - Google Patents

Abstract

920,973. Reciprocating sieves; pneumatic separators. GENERAL MILLS Inc. May 22, 1959 [May 22, 1958], No. 17576/59. Class 117. [Also in Group I] The apparatus for milling and sifting grain &c. disclosed in Specification 920,972 is modified in that the third pair of milling machines 116, 118, Fig. 1, is mounted, at the top of the frame 10, in the same housings 124 and 126 as the first pair of milling machines 100 and 102. The tailings from the oppositely reciprocating and balanced sieves 36 and 38 are conveyed upwardly, by pneumatic conveyers 113, 115, into cyclone separators 117, 119 located above the said housings and connected by pipes 121 to a fan. The tailings deposited from the streams of air in the cyclone separators pass through valves 129, the milling machines 116, 118, conduits 125, 127, sieves 40, 42, milling machines 120, 122, sieves 44, 46 and final outlets 123. In an alternative arrangement, the milling machines 116, 118 receive stocks from additional sieves (not shown) and the sieves 36, 38 then discharge their tailings directly into the sieves 40, 42. In other alternative arrangements, the pneumatic conveyers 113, 115 are connected either to the intermediate outlets 96, 97 of the sieves 32, 34 to receive siftings passing through their screens 76, or to the outlets 123 to recycle the tailings. In yet another arrangement, Fig. 2, a frame 151 supports upper and lower pairs of oppositely reciprocating, balanced sieves 153, 155 and 157, 159. Roller milling machines 166, 175 are mounted, preferably within a single housing, at the top of the frame and roller milling machines 169, 177 are mounted on the ends of the frame. Stock is fed, through an inlet 167, into the machine 166, which discharges milled stock into the sieve 155, from which a fraction passes through the machine 169 and the sieve 159. A fraction of the stock, e.g. tailings, from this sieve is then fed, by a pneumatic conveyer 171, into a cyclone separator 173 and thence, through a valve and the machine 175, into the sieve 153. A fraction of the stock from this sieve passes through the machine 177 into the sieve 157. Sifted fractions of the milled stock are discharged from the sieves 157 and 159 through outlets 179. Specification 2508/1867 also is referred to.