US2620841A

US2620841A - Method of removing husks from oats

Info

Publication number: US2620841A
Application number: US229765A
Authority: US
Inventors: Jacobson Sven
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-10-19
Filing date: 1951-06-04
Publication date: 1952-12-09
Anticipated expiration: 1969-12-09

Description

Dec. 9, 1952 s. JACQBSON 4 METHOD OF REMOVING HUSKS FROM OATS Filed June 4, 1951 2 SHEETS-Sl-IEET 1 Dec. 9, 1952 s. JACOBSON 2,620,841

METHOD OF REMOVING HUSKS FROM OATS Filed June 4, 1951 2 SHEETS-SHEET 2 Jar/61% c/a wZov/V iz'zj 142% J Warm Patented Dec. 9, 1952 UNITED STATES PTENT OFFICE METHODOF REMOVING HUSKS FROM OATS Sven Jacobson, Gothenburg, Sweden Application'June' 4, 1951, Serial No; 229,765- In SwedenOctober 19; 1944 4: Claims. 1.

This application is. a. continuation-in-part: of UnitedStates application Serial No. 622,601, filed October 16, 1945', and. subsequentlyabandoned.

Cereals, for instance cats, have. usually been hulled after being subjected to. a suitable preliminary operation by being passed througha husk removing machine in which. the husks are removed mechanically, for example between apair. of stones. The usual methods however allhave the disadvantage that: the grain" toazgreat extent becomes worn and broken resulting. in considerable loss in the finished product.

The present invention has for its purpose to provide a method in which the'abovementioned disadvantages are avoided andwhich will be simpler than .thehithertousedmethods, since it can be used withoutgrading intosizes and which need not be preceded by a drying process to dry the grain.

According to my invention, theoats are subjected during a suflicient length of time toaerodynamicaction to force open the husks or/and break them off and thereby layabare the kernels.

Two embodiments of apparatus for carrying out the invention are illustrated in the accompanying drawing in which Fig. 1' is an apparatus for treating comparatively smallbatch'es of oats and Fig. 2 shows an apparatus for the continuous treatment of greater quantities. Fig, 3 shows an apparatus, which combines the advantages of the apparatuses according to Figs. 1 and 2.

In Fig. l the numeral I designates'a cylinder of perforated plate'or a screen, which is 1 connected to an unperforated conical part 2. A pipe 3 is connected to the bottom of the conical part 2 and at its other end is connected to a source of pressure for instance a compressor or a blower not illustrated in the drawing. Theupper end of the cylinder is closed by a piston 4, which is;preferably adjustable for reasons whichwill be apparent fromthe following.

The'huskingor hulling process is carried out in the following manner; A suitable quantity of cats is introduced" into theapparatus and the air pressure is turned on. Thecompressed air flows up into the cylinder, where itexpands and then escapes from the cylinder byway. of the. perforations. The cats are thrown up into the cylinder and caused to circulate rapidly by the stream of air and are repeatedly exposed to the action of the air. During the operation, the husks are forced open and removed from the kernels. The powerful stream of air forces its way under the husks, which are opened up more or less like an open umbrella. The husks are then broken on,

either through the direct-aerodynamic action of the air or through the impact of the oats against eachother, or against thewalls of thecylinder; At the higher pressures the husks will be removed without the piston 4 and the piston should in these cases be removed; In this case means must be provided for gradually retarding the velocity of the. oats, for instance a sufiiciently long free trajectory or a cyclone. At the-lower pressures, however; the effect will be increasedxif the piston is adjusted in a suitable manner sothattheoats are thrown against it. It should benotedzhowever, that the effect is decreased'iffithe piston is positioned too close tothe mouth: ofthepipe'3. The piston can in each. individual case be ad. justed so that the maximum client is obtained.

The method can be carried out by continuing the operation until a certain quantity, for instance, 20 or 25% or more, ofthe oats hasbeen hulled. The operation is then discontinued and the husks and the hulled cats are" removed, after which the operation is resumedand continued in one or more further steps until the remaining oats have been hulled ascompletely as possible. Alternatively, the operation oan'be carried out in a single steppreferably with higher pressure and during a greater length of time until -or or more of the oats have been hulled.

It has been found that the pressure at the mouth of the pipe 3 should be of the magnitude of at least 2 leg/cm: higher than" pressure outside of the cylinder, and a difference in pressure of between '7 kg./cm. and 10 kg.'/cm. has been found suitable. The velocity of the air is'preferably of the magnitude 300 III/sec. or more; The time required'for completion of'the operation is considerably increased if the pressure is lowered and; can be somewhat shortened'by raising the pressure; The greater thepressure, hoWeWLthB greater will; be the loss due to breakage of the kernels and the aforesaid pressure difference should not materially exceed 12 kg/cmF" The time is also influenced'by the quantity, of. air per unit of time and by the quantity of oats inthe batch. It has insome casesbeen foundof. ad.- vantage to increase the new of air by, increasing the diameter of the. pipe3I and atthe Same time lowering the pressure in order todiminish. the breakage.

The apparatus illustrated in Fig. 1 is especially useful for making a quick and reliable examination of a sample of oats for determining the quality of a delivery of cats.

An apparatus for continuous operation is shown in Fig. 2, in which the cylinder 5, the conical part 6, the pipe I and the piston 8 have the same functions as in the apparatus shown in Fig. 1. At the bottom of the conical part 6 there is, however, an entrance pipe 9 for the oats, surrounding the air pipe I and extending somewhat above the mouth of the latter. The pipe is enlarged somewhat at its lower end, which is located in a container I for oats. A supply pipe I I leads from a larger container to the container I0 and serves to supply oat to the container continuously as oats are removed to the cylinder. A pipe I2 from the bottom of the conical part 6 serves to remove the hulled oats from the cylinder.

Fig. 3 shows an apparatus which may be said to combine the advantages of the batch method as used in the apparatus shown in Fig. l and the continuous method as used in the apparatus shown in Fig. 2. Before admitting the oats to the apparatus shown in Fig. 3 it is, however, necessary to grade them to size, the diameter of the grains of oats in each batch varying only within an interval of one to two tenths of a millimeter. Each grade of oats is treated separately in the apparatus.

The numerals I3 and I4 designate separate cylinders of perforated plate. The conical part I5, the pipe I6 and the piston I'I correspond to, and have the same functions as, the correspondingly numbered parts in Fig. 1. The cylinder It has a greater diameter than the cylinder I3 and an annular opening I8 is formed between the two cylinders. Whole grains of oats, husks and kernels escape through the opening I8 and are collected in a circular trough I9 under the opening I8 from which they are blown by the escaping air out into a chamber 20 surrounding the cylinders I3 and I4. The walls of this chamber are made as sieves, the size of the perforations being determined by the size of the oats being treated. The bottom wall of the chamber 20 is conical and slants toward an annular opening 2| leading back to the entrance to the cylinder I3. The husks and the hulled oats pass through the perforations of the sieve, but oats that have not been hulled pass back to the cylinder I3 and are again subjected to the action of the air. A fresh quantity of graded oats is supplied to the chamber 20 through a pipe 22 and by way of the cone I passes into the cylinder I3 for treatment together with the tailings. The quantity of oats entering through the pipe 22 can be regulated by suitable mechanical (weighing), electrical or optical means to correspond to the amount of hulled oats escaping from the chamber 20. In this manner, it is possible to adjust the apparatus to work evenly under the most economical conditions. In this apparatus, the most easily hulled oats are immediately removed and the breakage is reduced to a minimum, while more resistant oats receive the required treatment to remove their husks. The stationary sieve forming the bottom wall of chamber 20 may, if desired, be replaced by a suitable movable sieve to increase the effect thereof.

As previously set forth, the piston 4 or its equivalent, while in some cases desirable, is not essential to the operation of the apparatus. If present it should be adjusted to a position, readily determinable by trial, affording optimum de- '4 hulling with minimum kernel breakage. Obviously, the position of the piston for optimum results will vary with the pressure of the air and the velocity of the oats.

The method can be used for hulling either dry or undried oats. Instead of air under pressure, a powerful flow of any other suitable gas, for instance steam, may be used. The chamber in which the hulling takes place need not be cylindrical, but may have any other suitable shape. It need not necessarily be made of perforated plate, but may instead have one or more suitably located escape openings for the air.

I claim:

1. The method of hulling oats comprising the steps of introducing the oats to be hulled into a chamber having an admission opening for a stream of compressed air and an escape opening for said air, and subjecting the oats to the repeated action of a continuous stream of compressed air entering through said admission opening and into contact with the oats to be hulled at a pressure of from about 2 kg./cm. to about 12 kg./cm. above that of the surrounding atmosphere, whereby the husks are forced or broken open and removed from the kernels solely by the direct aerodynamic action of said air on the oats.

2. The method of hulling oats comprising the steps of subjecting a mass of cats to be hulled within a confining chamber to the repeated action of a continuous, upwardly directed stream of compressed air projected into contact with said mass at a pressure of from about 2 kg./cm. to about 12 kg./cm. above that of the surrounding atmosphere and which passes with substantial freedom through said chamber, whereby the husks are forced open and removed from the kernels solely by the direct aerodynamic action of said air on the oats.

3. The method according to claim 1 wherein the air enters the admission opening at a pressure of from 7 kg./cm. to 10 kg./cm. above that of the surrounding atmosphere.

4. The method according to claim 2 wherein the air enters the admission opening at a pressure of from 7 kg./cm. to 10 kg./cm. above that of the surrounding atmosphere.

SVEN JACOBSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 124,848 Paige Mar. 19, 1872 226,471 Arbuckle Apr. 13, 1880 258,912 Goessling June 6, 1882 269,741 Taggart Dec. 26, 1882 1,699,441 Negro 1- Jan. 15, 1929 1,874,150 Anger Aug. 30, 1932 1,950,069 Stein Mar. 6, 1934 FOREIGN PATENTS Number Country Date 20,917 Great Britain Oct. 16, 1905 433,034 Great Britain Aug. 7, 1935