US3595290A

US3595290A - Apparatus for comminuting grain

Info

Publication number: US3595290A
Application number: US831468A
Authority: US
Inventors: Toni Golubinov Tassev
Original assignee: DSP BULET
Current assignee: DSP BULET
Priority date: 1968-06-11
Filing date: 1969-06-09
Publication date: 1971-07-27
Anticipated expiration: 1988-07-27
Also published as: CH498656A; DE1929692A1; FR2010672A1; YU142469A; BE734322A; GB1268534A

Abstract

Am apparatus for comminuting grain in which a feed rotor entrains the grain along its underside and propels the grain at high velocity against blades rotated in the opposite direction on a comminuter rotor which cooperates with fixed teeth attached to the housing walls.

Description

United States Patent Inventor Toni Golubinov Tassev Sofia, Bulgaria Appl. No. 831,468 Filed June 9, 1969 Patented July 27, 1971 Assignee DSP Bulet Sofia, Bulgaria Priority June 11, 1968 Bulgaria 101 14 APPARATUS FOR COM MINUTING GRAIN 2 Claims, 3 Drawing Figs.

U.S. Cl 146/123,

241/154,241/186 Int. Cl. H. B02b 3/08, B02c 13/09 Field of Search 146/123;

[56] References Cited UNlTED STATES-PATENTS 1,861,779 6/1932 Bornhauser 1,840,893 1/1932 Giddings 3.436028 4/1969 Koehnen et al FORElGN PATENTS 791,927 10/1935 France 27,635 4/1955 Finland 1,157,062 11/1963 Germany Primary Examiner-Andrew R. Juhasz Assistant Examiner-Z. R. Bilinsky At10rney- Karl F. Ross ABSTRACT: Am apparatus for comminuting grain in which a feed rotor entrains the grain along its underside and propels the grain at high velocity against blades rotated in the opposite direction on a comminuter rotor which cooperates with fixed teeth attached to the housing walls.

PATENTED M27 :97:

TONI GOLUBINOV TASSEV INVEN'I'OR.

APPARATUS FOR COMMINUTING GRAIN The invention relates to an apparatus for comminuting grain and, more particularly, to an inertial breaker for subdividing grain, e.g. to obtain a flour fraction.

inertial breakers for commin uting grain have been provided heretofore with movable or immovable striking bodies to which the grain is fed. In general, the grain flows freely to the impact members which engage the grain and break it up prior to passage of the grain through a sieve. Particles which do not pass through the screen are further comminuted by a hammer or blade. It has been found that this system yields a heterogeneous product made up, as is apparent, by the particles which freely pass through the sieve and particles which are crushed through the latter.

The rotors used for these purposes are complex and are not subject to even wear so that balancing them creates a dilficulty.

it is an object of the present invention to provide an improved apparatus for comminuting grain.

This object is achieved, in accordance with the present invention, by providing an impact rotor drum, fitted with externally projecting toothed blades and rotated in one sense while a counterrotating feed rotor constitutes an impeller entraining the grain between the rotors and in the direction of the blades at high velocity. As a result of the impact of the grain upon the blades, the relative speed of each grain and the impact surface is increased and improved grinding is carried out. The fraction of undesirable flour may be reduced to 20 percent and it is possible to obtain a homogeneous product without a sieve.

The above and other objects,'features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a vertical section through the apparatus of the present invention;

FIG. 2 is a cross section illustrating how the blades of the impact rotor are affixed to the rotor body; and

FIG. 3 illustrates a detail view of the repellers carried by the housing.

From the drawing, it will be apparent that the grain-breaker apparatus, as distinct from a crushing device, comprises a housing 1 rotatably receiving a feeding rotor or impeller 2, a regulator or guide 3 for passing the grain at a controllable rate along the underside of the impeller 2 and an impact rotor 5 which is also rotatably mounted in the housing. The rotor 5 is formed along its periphery with angularly spaced arrays of radially projecting toothed knives or blades 6 of generally trapezoidal configuration. Along the path of the working rotor 5 and especially of grain projected thereby to the left, there are provided arrays of toothed repellers 4 affixed to the housing 1. The toothed repellers 4 thus constitute fixed blades (FIG. 3) which intercept the grain particles cast in the counterclockwise sense by the rotor 5 and cooperate with the latter to further comminute the grain. The feeding rotor or impeller 2 is mounted on the shaft of an electric motor (not shown) and is driven at about 3000 r.p.m., the periphery of the rotor 2 being provided with fan blades to facilitate the projection ofthe grain tangentially into the path of the counterrotating rotor 5. The latter is mounted on the shaft of another electric motor (not shown) with the same rotary speed, i.e. 3000 r.p.m.

On the periphery of the drum of the rotor 5, are formed trapezoidal slots (FIG. 2) in which the toothed blades 6 are fitted and separated by adjusting lamellas 7, the thicknesses of which determine the clearance between the blades 6 and hence the particle size of the comminuted grain. The regulator 3 comprises a steel surface running along the periphery of the rotor 2 and the entire throat of the breaker and which can be adjusted toward and away from the latter via an adjusting slot, to control the rate at which grain is fed through the device.

As can be seen from FIGS. 1 and 3, the toothed repellers 4 may be attached to the housing in such manner that they can rotate about their axes for ad ustment and to replace wornout teeth. The grains enter the path of the feeding rotor at high speed and are entrained in the counterclockwise sense along the underside of the rotor and are projected tangentially from the latter into the path of the counterclockwise rotating member 5. The stream of grain is thus tangential to the opposite side of rotor 5 from that at which the grain leaves the rotor 2 and hence encounters the blades 6 as the latter move in the opposite direction. By reason of the acceleration imparted to the grain by the rotor 2 and the countermovement of the blades 6, the grain passes into the path of these blades at a relative speed much higher than is obtainable with conventional systems. Upon impact of grain with the blades, the grain is subdivided into small pieces and a small percentage of undesirable flour fraction. The grain particles are entrained by the blades through the arrays of repellers 4 and finally are projected at high velocity upwardly out of the apparatus. The apparatus, of course, operates without a sieve, has a simplified construction since it omits the sieve and bearings and belts commonly used in other apparatus. The wear of the blades is less so that they last longer than the blades of conventional hammers and the profile blade 6 has been found to have improved efficiency.

lclaim:

1. A grain comminuter comprising a housing formed with a grain inlet; an impeller rotatably mounted in said housing for projecting grain in one direction along a path; an impact rotor mounted rotatably in said housing and formed with a peripheral array of outwardly projecting blades displaceable on' said rotor to intercept said path and rotatable in a direction opposite the direction in which said grain is projected by said impeller; and at least one array of repeller blades attached to said housing for intercepting grain entrained by said impact motor and cooperating therewith to comminute the grain.

2. The grain comminuter defined in claim 1 wherein said impeller is a rotor provided with fan blades and is rotated in one sense for sweeping said grain along one side of the impeller rotor, 'said comminuter further comprising a regulator extending from said opening along said side of said impeller for controlling the rate of flow of the grain therethrough, said impact rotor being formed along its periphery with angularly spaced slots, each receiving an array of toothed impact blades separated by spacer lamellae establishing the distance between the toothed blades, said impact rotor being positioned to bring the side thereof opposite the side of the impeller rotor into engagement with the grain, said repeller blades being rotatably adjustable to replace the effective cutting edges thereof.

Claims

1. A grain comminuter comprising a housing formed with a grain inlet; an impeller rotatably mounted in said housing for projecting grain in one direction along a path; an impact rotor mounted rotatably in said housing and formed with a peripheral array of outwardly projecting blades displaceable on said rotor to intercept said path and rotatable in a direction opposite the direction in which said grain is projected by said impeller; and at least one array of repeller blades attached to said housing for intercepting grain entrained by said impact motor and cooperating therewith to comminute the grain.

2. The grain comminuter defined in claim 1 wherein said impeller is a rotor provided with fan blades and is rotated in one sense for sweeping said grain along one side of the impeller rotor, said comminuter further comprising a regulator extending from said opening along said side of said impeller for controlling the rate of flow of the grain therethrough, said impact rotor being formed along its periphery with angularly spaced slots, each receiving an array of toothed impact blades separated by spacer lamellae establishing the distance between the toothed blades, said impact rotor being positioned to bring the side thereof opposite the side of the impeller rotor into engagement with the grain, said repeller blades being rotatably adjustable to replace the effective cutting edges thereof.