IMPROVEMENTS IN AND IN APPARATUS FOR THE TREATMENT OF MAIZE TO SEPARATE THE GERMS AND OBTAIN PROVISIONAL
Year: 1881

page_text: LETTERS PATENT to Thomas Muir, of Glasgow, in the County of Lanark,
Merchant Miller, for an Invention of "IMPROVEMENTS IN AND IN APPARATUS
FOR THE TREATMENT OF MAIZE TO SEPARATE THE GERMS AND OBTAIN
PROVISIONAL SPECIFICATION left by the said Thomas Muir at the Office
of the Commissioners of Patents on the 29th July 1881.
THOMAS MUIR, of Glasgow, in the County of Lanark, Merchant Miller.
"IMPROVEMENTS IN AND IN APPARATUS FOR THE TREATMENT OF MAIZE TO
SEPARATE THE GERMS AND OBTAIN HIGH QUALITY MEAL AND FLOUR."
My present improvements have reference to so treating maize that the germs are
more thoroughly, indeed practically, completely eliminated, and meal or flour is
obtained of higher quality, so much higher indeed as to be of great value for use
by brewers, distillers, starch makers, and others. Whilst securing by my novel
treatment the advantages just named, I avoid the production of large quantities of
"dead flour."
After sizing maize I break it by suitable rolls constructed and operating as
hereafter described. I next sift the product and size the grit. Each size of grit
of necessity contains the germs or parts of germs of the same size. Afterwards
I pass the grit or semolina between rolls with suitable surfaces, break the fleshy
parts, and flatten the germs. The germs are next sifted out by reels or otherwise.
In carrying my Invention into practice I proceed in manner following:.
First. I size the maize into two or more sizes, ordinarily using for that purpose
rotating cylinders with wire mesh or perforated metal.
Second. Each size of corn is passed to break rollers. Rollers of chilled iron, grooved
or lined diagonally on the surface are preferred, and sizes 30 inches long, 15 inches
diameter, grooves or cuttings 6 to 8 to the inch, and with a slight differential
speed, say, 110 to 120, are found to answer. The size, markings, and speed however
Duine 71

page_text: would usually be determined by the condition and quality of the corn and the
quantity it is desired to run through.
Third. The product from the said break rolls is passed to reel No. 1 covered with,
say No. 4 wire mesh: The overtails of this reel not being sufficiently broken,
and the germs only partially disengaged, are passed to another set of rolls. The
out-siftings however are passed to reel No. 2, which latter is covered with No. 16
or 20 wire cloth. The outsiftings of No..2, being the meal or flour incidental to
the breaking, goes for a second quality meal or flour, or if fairly free from germs,
may go to join the germless meal hereafter described.
Fourth. The overtails of reel No. 2 (being all sizes of grit, which will pass, say, a
No. 4 mesh, and will pass out and over a No. 16 mesh) is then passed to a sizing
rotating reel or cylinder covered with different sizes of wire cloth, say, from No. 10
to No. 5 inclusive. A revolving external freeing brush should be used. The space
required for No. 6. and No. 7 mesh is about twice as much as is necessary for any
of the other sizes. The grit is thus obtained in sizes.
Fifth. Each size of grit, which also has the like size of germ mixed with it, is
now passed on to and between rotating rolls of any suitable material and con-
struction, by preference, with some slight differential speed. The said rolls must
not be too smooth; a porous or biting surface is best. Cast iron rolls, case hardened,
come to their work more quickly than chilled iron rolls. Caro must be taken not
to press the rolls too close together, doing so would cake the grit and nip or break
the germs.
Sixth. The product of each roll is now passed into a reel or sifter, which allows
the meal or flour to pass through, but the flattened germs are dropped over the
tail. If desired, the meal or flour may be further ground by rolls, stones, or
otherwise. A lift and drop feed to the reel is desirable, inasmuch as it has a
tendency to break up any cake from the rolls.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Muir in the Great Seal Patent Office on the 28th January
1882.
THOMAS MUIR, of Glasgow, in the County of Lanark, Merchant Miller.
"IMPROVEMENTS IN AND IN APPARATUS FOR THE TREATMENT OF MAIZE TO
SEPARATE THE GERMS AND OBTAIN HIGH QUALITY MEAL AND FLOUR."
My present improvements have reference to so treating maize that the germs are
more thoroughly, indeed practically, completely eliminated, and meal or flour is
obtained of higher quality, so much higher indeed as to be of great value for use
by brewers, distillers, starch makers, and others. The separated germs are of high
value for feeding horses, cattle, and other animals. Whilst securing by my novel
treatment the advantages above named, I avoid the production of large quantities
of "dead flour," or of what I now call " break meal or flour." The marketable
products from clean whole maize treated under my Invention may be any of those
under the following heads, but I prefer the first and second-First (a), meal from
the grit or fleshy parts; (b), germs and skins or pellicles, and (c), break, meal or
flour; the germs and skins or pellicles are suitable for feeding horses, and the break
meal or flour for feeding cattle. Second (a), meal from the grit or fleshy parts;
(b), germs; (c), skins or pellicles, and break meal and flour; the germs by them-
selves are suitable for yielding oil, say, by grinding, heating, and pressing, and the
skins or pellicles and break flour, when the former is ground, and the two mixed
together, for feeding cattle. Third (a), meal from the grit or fleshy part;
(b), germs; (c), skins or pellicles and light germs, and (d) break meal or flour;
the germs are fit for yielding oil, the skins or pellicles and light germs may be
mixed with wheat, brau, or sold as bran, and the brake meal or flour for feeding
cattle.
After sizing the maize (of course after cleaning, say, through a reel with No. 8 mesh
at one end, and inch meshes at the other), I break it by suitable rolls constructed
and operating as hereafter described. I next sift the product and size the grit.
Each size of grit of necessity contains the germs or parts of germs of the saine
size. Afterwards I pass the grit or semolina between rolls with suitable surfaces,
break the fleshy parts, and flatten the germs. The germs are next sifted out by
reels or otherwise. Stones may be utilized (and there are many of them fit for the
purpose in mills at present working) for the first break above mentioned as
substitutes for rolls, but they have the disadvantage of producing more break or
"dead" meal or flour. Buhr stones when so used should be of medium grit, and
when of 4. feet diameter run at 200 revolutions per minute, the bed stone being
in 12 to 15 divisions with radial furrows, and the runner with the same number of
divisions, the furrows having a draught of 3, of an inch to the foot behind the
centre, a working surface at the skirt of 4 inches wide, and a gradual rise from
that working surface to the eye of about 1/2 an inch.
In carrying my Invention into practice I proceed in manner following:-First, I
size the maize into two or more sizes, ordinarily using for that purpose rotating
cylinders with wire mesh or perforated metal. When zinc is used, say, No. 13 and 14,
a worm sizer is best. Second, each size of corn is passed to break rollers, such rollers -
being adjusted to suit the size. Rollers of chilled iron, grooved or lined diagonally
on the surface are preferred, and sizes 30 inches long by 15 inches diameter, with
grooves or cuttings 3 to 8 to the inch (4 being preferred), and with a slight
differential speed, say, 110 to 120, are found to answer, but the differential surface
speeds may vary as much as one to three, and when the maize is not very hard I

page_text: prefer one to three. The size, markings, and speed however would be determined
by the condition and quality of the corn and the quantity it was desired to run
through; a spiral grooved feed roll is preferred. As hereinbefore mentioned,
horizontal or like mill stones may be used for effecting this break instead of rolls.
Third, the product from the said break rolls is passed to reel No. 1 covered with,
say, No. 10 wire mesh on one half, and No. 4 on the other. The overtails of this
reel not being sufficiently broken, and when found to have the germs only partially
disengaged are passed to another set of rolls or to the rolls working the smaller
size of maize. The outsiftings of the part covered by No. 10 however are passed
to reel No 2, which latter is covered with wire cloth, say, No. 16 to 20, No. 18
being preferred. The outsiftings of the part covered by No. 4 is the mixed grit,
which has afterwards to be sized, and the germs. The outsiftings of No. 2, being
the break meal or flour, goes for a second quality meal or flour, or if fairly free
from germs, may go to join the germless meal hereafter described. Fourth, the
overtails of reel No. 2 and the outsiftings of the No. 4 cloth on No. 1 reel, being
all sizes of grit which will pass through, say, a No. 4 mesh, and will pass out and
over a No. 18 mesh, is then passed to a sizing rotating reel or cylinder, say, 20 feet
long, 30 inches diameter, and driven at 18 revolutions per minute, covered with
different sizes of wire cloth, say, from No. 12 to No. 5 inclusive. As will be evident
an inside worm is desirable. A revolving, or it may be a fixed external freeing
brush should be used on the said reel. The grit is thus obtained in sizes. It will
be evident that a series of reels may be used with different meshed cloth.
Fifth. Each size of grit, which also has the like size of germ mixed with it, is now
passed on to and between rotating rolls (smooth rolls are best) of any suitable
material and construction, by preference, with some slight differential surface speed,
say, 115 to 120; a higher differential speed has a tendency to nip or break the
germs. The said rolls must not be too smooth. A porous or biting surface which
takes in the feed freely is best. Spiral grooved feed rolls are preferred.
rolls, case hardened, come to their work more quickly than chilled iron rolls. Care
must be taken not to press the rolls too close together, doing so would tend to
cake the grit and nip.or break the germs.
Cast iron
Sixth. The product of each set of rolls is now passed into a suitable reel or sifter
covered with wire cloth or its equivalent, having openings to allow the meal or
rolled grit to pass through, but to cause the flattened gerins to pass out and over
the tail end. The meshes on the respective reels are each one half to a whole
number finer than the mesh by which the grit was sized. Polygonal reels are
preferred, as the action of such reels will sufficiently break up any material caked
by the rolls. When desired, the meal or flour may be further ground by rolls,
stones, or otherwise, and thereafter dressed through silk or wire reels to any
required fineness.
Dressing the degermed maize is not required when the meal is to be used in the
production of alcohol, but is desirable when to be used in the production of alo
and stout. The break flour is not materially objectionable in distilleries, but is
decidedly so in breweries.
Under a modification which I have found to answer well, I remove the light
germs and some of the skins or pellicles immediately after the grit is sized by
currents of air impelled through trunks or equivalents. The treatment under this
modification is therefore sizing the maize, breaking, sifting, to remove the break
meal or flour, sizing the grit, removing the light germs and some of the skins or
pellicles, rolling and reeling out the germs and remaining skins or pellicles.
Germless maize meal obtained by one break of the maize on rolls or stones, sizing
of the grit, one rolling to flatten the germs, and the subsequent sifting out of the
germs is meal of better quality secured with less special plant and at much less
cost than by any other treatment.
A modification under my Invention consists in taking the maize after cleaning
and without sizing, breaking it in bulk, then sifting out the break flour, effecting
the sizing of the grit by reels rolling and sifting out the germs. The one sizing,

page_text: that is, sizing the grit after breaking, is simpler than the double sizing, answers
well in practice and reduces the cost for plant.
Having now described the nature of my said Invention and particularized the
same in such manner that others may carry my improvements into practice, I
claim,
First. Treating maize, substantially in the manner or order herein described to
separate the germs and obtain high quality meal or flour.
Second. The apparatus or appliances in combination for obtaining the desired
result, substantially as described.
In witness whereof, I, the said Thomas Muir, have hereunto set my hand
and seal, this Twenty-seventh day of January, in the year of our Lord
One thousand eight hundred and eighty-two.