GB887322A - Improvements in rollermills for the grinding of cereal products - Google Patents

Abstract

887.322. Roller mills. SIMON Ltd., HENRY. Mav 1. 1958 [May 13. 19571. No. 15087/57. Class 59. [Also in Group XXX] A roller mill comprises an enclosing and supporting framework, a feeding means arranged to accept material from an inlet spout and spread it so that it is discharged as a wide curtain of uniform density, a pair of grinding rollers which are so related to the feeder that the curtain of material discharged from the feeder passes directly into the nip of the grinding rollers, and below the grinding rollers a comparatively shallow collecting hopper which is movably supported from the machine frame and connected to a source of vibratory motion, the base of the collecting hopper being downwardly sloped towards an outlet port situated at the lowest end of the hopper, the shape of the hopper and the amplitude and frequency of the vibratory motion applied to it being such as to ensure that collected material will be maintained in a state of fluidity that will enable it to flow freely to and through the outlet port. The roller mill shown in Figs. 1 and 2 comprises two pairs of grinding rollers 3, 4 supported in a framework 1, each pair of rollers being associated with an intake hopper 2 and with a collecting hopper 5 which is arranged to pass ground material through an outlet 6 to a position where it can be collected by pneumatic or other conveying means. The hopper 2 is shaped so as to receive stock from a central feed spout 7 and spread it over the length of the hopper outlet which is substantially equal to the lengths of the grinding rollers. The hopper 2 is supported from the framework 1 by means of resilient rubber-like sealing members 8 which allow the hopper base to vibrate under the control of vibratory means 9. The hopper 5, which is provided with a porous member 13 through which air can be passed into the hopper to assist in the fluidising of material carried thereon, is supported from the framework 1 by means of resilient rubber-like members 12 which allow it to vibrate under the control of vibratory means 14. The hoppers 2, 5 may be operated by a common source of vibratory motion. In a modification, Fig. 4, stock is fed to each pair of grinding rollers by means of a vibrating spreader feeder 22 which comprises a tapered spreader tray 23 having guide vanes extending parallel to the direction of movement of the stock. Upward extensions 25 of the tray carry a pivotally-mounted tilting shoot 26 which is provided with automatic counter-balancing means which regulate the angle of tilt of the shoot in accordance with the input rate of feed of material into a spout 29. Overload or cessation of the input feed is indicated by means of signal-operating switches 30 positioned before the upper and lower limits of travel of an extension 31 of the shoot 26. The signals may control means for moving one of the grinding rollers away from the other if the input feed ceases and for restoring it to the grinding position when the feed recommences. Means may also be provided to cause the spreader tray to stop vibrating when the grinding rollers are parted. The stock after being ground falls into collecting hoppers 38 each of which is mounted on lints 39 for vibratory movement in a direction which is substantially parallel to the roller axes. The outlet from each hopper 38 is connected by a flexible sleeve 40 to a rotary feeder 41 from which it passes into a conveying pipe 42. Each rotary feeder is driven from the grinding roller driving mechanism. The stock input pipes 61 are arranged to enter the machine cover at positions on a centre line which is parallel to the roller axes. The pipes 42 are carried through the machine cover near the pipes 61 so that each set of pipes may be enclosed in a common trunk 62. Specifications 701,136 and 842,560 are referred to.