IMPROVEMENTS IN MILLS FOR REDUCING GRAIN AND OTHER SUBSTANCES TO A PULVERIZED STATE, AND IN THE APPARATUS FOR DRESSING OR BOLTING PULVERIZED SUBSTANCES
Year: 1840

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ALEXANDER
DEAN and EVAN EVANS, both of Birmingham, in the County of Warwick,
send greeting.
WHEREAS we did, by petition, humbly represent unto Her present most
Excellent Majesty Queen Victoria, that, after considerable application and
expense, we had invented certain "IMPROVEMENTS IN MILLS FOR REDUCING GRAIN
AND OTHER SUBSTANCES TO A PULVERIZED STATE, AND IN THE APPARATUS FOR
DRESSING OR BOLTING PULVERIZED SUBSTANCES," and Her said Majesty, being
willing to give encouragement to all arts and inventions which may be for the
public good, was graciously pleased, by Her Royal Letters Patent under the
Great Seal of the United Kingdom of Great Britain and Ireland, bearing date at
Westminster,, the Twenty-fourth day of September, One hundred and forty,
in the fourth year of Her reign, for Herself, Her heirs and successors, to give
and grant unto us, the said Alexander Dean and Evan Evans, our executors,
administrators, and assigns, Her special license, full power, sole privilege
and authority, that we or they, by ourselves or themselves, or by our or their
deputies, servants or agents, or such others as we or they should agree with
(and no others), during the term of fourteen years from the date of the said
Letters Patent, should and lawfully might make, use, exercise, and vend our
said Invention within that part of Her said Majesty's Dominions called
England, Her Dominion of Wales, and Town of Berwick-upon-Tweed, and
also in all Her Majesty's Colonies and Plantations abroad, in such manner as
to us, our executors, administrators, and assigns shall seem meet, and as that we
or they shall enjoy the whole profit and advantage arising by reason of the said

page_text: Invention during the said term of fourteen years, and for that end Her said
Majesty requires and strictly commands all Her subjects whatsoever within
England, Wales, and Berwick-upon-Tweed, and also in the Colonies and Plan-
tations aforesaid, that they shall not, neither directly nor indirectly, make, use,
or put in practice our said Invention or any part thereof, nor in anywise
counterfeit, imitate, or resemble the same, nor make any addition thereto or
subtraction therefrom, whereby to pretend himself or themselves to be the
inventor or inventors thereof; and whereas the said Letters Patent also
contain a proviso obliging us, the said Alexander Dean and Evan Evans,
particularly to describe and ascertain the nature of our said Invention, and
in what manner the same is to be performed, by an instrument in writing
under our hands and seals, and to cause the same to be enrolled in Her
Majesty's High Court of Chancery within six calendar months next and imme-
diately after the date of the said in part recited Letters Patent, as in and by
the same (reference being thereunto had) will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, we, the said
Alexander Dean and Evan Evans, do hereby declare that our said Invention is
described and ascertained in manner following, and by the aid of eighteen Sheets
of Drawings hereunto annexed, and the writing thereon, that is to say:-
Our improvement in mills relate in part to that description called portable,
and which were introduced by Napolean Buonaparte into the French army.
This mill will be found described, in the thirty-fifth volume of the Transactions of
the Society of Arts, and the nature of our improvements in mills will be rendered
more clear by reference thereto. Our guiding plates are cut upon the surface
in a similar manner to common millstones, and for a similar purpose; but, in
addition to the cut surface of the guiding plates, we have a portion of the
outside circumference of each plate with a plain surface, so that the substance
which has been coarsely pulverized by the teeth of the plates become still
further comminuted by afterwards passing between the two plain surfaces
which are nearly in contact, and are only kept apart by the substance to be
-pulverized, and which escapes from between the grinding surfaces of the
plates at their external circumferences. The French military mill, though
capable of producing such flour as might be tolerated by an army, was not
capable of producing impalpable meal, the Invention has therefore never been
generally adopted as a domestic mill on account of its inefficiency. This mill
contemplated nothing more than grinding. The operation of dressing, if
performed at all, was done in a separate and totally distinct machine. . Another
objection to its use as a domestic mill arises from the metal grinders, which
in practice are found to make the flour of a darker colour than the flour

page_text: produced in the ordinary manner by common millstones. For the purpose of
grinding beans into flour the colour may not be objectionable, but for fine
bread the colour of the flour is an object of importance: In the French
military mill the grinding surfaces were placed in a vertical position, which
is prejudicial to the grinding operation. In our mill the grinding plates are
horizontal, as in common millstones, and where they are shewn on the Drawings
they are marked A.
Our "Improvements in Mills for Reducing Grain and other Substances to
á Pulverized State, and in the Apparatus for Dressing or Bolting Pulverized
Substances," are shewn on the eighteen Sheets of Drawings hereunto
annexed:-
Sheet is a front elevation of the mill. The part which contains the bolt-
ing or dressing apparatus is indicated by dotted lines; the grinding and
dressing are performed simultaneously, when it is desirable, or the dressing
apparatus may be thrown out of use, and the mill used merely to grind or
pulverize.
Sheet 2 represents a side elevation of the apparatus, the part indicated by
dotted lines containing the apparatus for dressing or bolting.
Sheet 3 represents the apparatus in side elevation, being a view of the
opposite side to that shewn on Sheet 2.
Sheet 4 represents the apparatus in plan.
The
Sheet 5 represents a vertical section through the center of the apparatus.
Sheets 1 to 5 inclusive shew more particularly the construction of "Mills
for Reducing Grain and other Substances to a Pulverized State." Motion
is given to the mill by the application of any suitable power to the handle B.
The substance to be pulverized is placed in the hopper or reservoir C, and
the quantity of grain or other substance which passes out of the hopper or
reservoir into the mill is regulated by adjusting the gage D. Section 7
contains views of the hopper or reservoir, and also another method of regu-
lating the quantity which passes from the hopper or reservoir to the mill.
regulator shewn on Sheet 7 is marked D. A series of wheels are used for
giving a proper velocity to the grinding plates, and a pulley, E, is used to
convey motion by means of a band or gut to the pulley F, which actuates
the working or moving part of the apparatus for dressing or bolting pulverized
substances. A fly wheel, G, is attached to an horizontal shaft, to equalize the
motion of the apparatus. The substance to be pulverized escapes from between
the grinding plates at their external circumferences, and passes into a box E.
A brush, I, Sheet 5, fixed to the revolving grinding plate, forces the sub-
stance which has been pulverized out of the box H at the aperture J,

page_text: (Sheet 1); from this aperture it passes into the dressing or bolting apparatus
(hereafter described), or when the pulverized substance does not require to
be dressed or bolted, then the aperture J is covered by a sliding plate K,
which is removed from the under side of the box H, and by its removal an
aperture is formed, out of which the grain or other substance passes from the
mill without passing through the apparatus for dressing or bolting. The
grinding plates have their distance apart regulated by means of the setting
screw L, which moves the lower plate further from or nearer to the upper
fixed plate, depending upon the direction in which the screw L is moved.
For producing fine flour the plates A, A, are placed very close together; but
when the substance pulverized is not wanted to be very fine, then the plates
are separated, so as to prevent the degree of pulverization which is required.
Sheet 6 exhibits in detail the construction of the grinding plates. Figure 1,
A, is a plan of the working face of the moveable plate or grinder. Figure 3 is
an elevation of the same, shewing it attached to the upright spindle, through
the medium of which the grinding or lower plate is a moved. Figure 7 is a
plan of the under sides of Figure 1 and Figure 3. Figure 4 is a vertical
section through the axis upon which the grinding plate turns. N is a stud
affixed to the revolving grinder, to remove the substance which has been
pulverized, and assists the brush I in discharging from the box II the
substance which has been pulverized. The stud M is chiefly useful to dis-
charge those substances which have been coarsely pulverized, and which do
not require dressing or bolting.
Sheets 8 and 9 exhibit a different method of regulating the distance of the
plates A, A, on Sheets I and 5; Sheet 9, shewing a front elevation of part of
the mill, but with the upright spindle removed. The method of adjustment
shewn on Sheets 8 and 9 is the one we prefer, because it admits of greater
accuracy than the other, neither is it so liable as the method shewn on Sheets 1
and 5 to get accidentally out of adjustment.
Sheet 10 shews an apparatus for pulverizing malt or other grain, where
the object is to make as little meal or flour as possible. To effect this object
the external edges of the plates A, A, are serrated or cut into teeth, and the
grain, as it passes between the two edges, becomes coarsley granulated or
pulverized. The grain to be pulverized is contained in a hopper or reservoir,
formed between two concentric vessels, and must be caught as it leaves the
nill in a suitably pulverized state. The method of giving motion and adjust-
ment to the grinding plate is similar to that shewn on Sheets 1 to 5 inclusive,
and will be understood without further description, by a careful inspection of
the Drawings on Sheet 10.

page_text: Sheet 11, Figures 1, 2, and 3, are representations of the external parts
of the dressing or bolting apparatus, indicated on Sheets 1, 2, 3, and 4, by
dotted lines. Figure 4 is a transverse section of the dressing or bolting
apparatus, shewing an end view of the axis upon which the brush is
mounted. Figure 5 is a vertical section shewing the spiral form of the
brush, and also the wirework or lattice through which the spirally formed
brush forces those pulverized particles which are small enough to pass through
the meshes or apertures formed in the wire gauze. The spiral brush moves
in contact with a trough of wire gauze, which has its length divided into, say,
four portions, as in Figure 5, and each of these portions of the length of the
trough is formed of wire gauze, varying in fineness or coarseness according
to the desired quality of the meal or pulverized substance. In Figure 5, W
indicates wire gauze of one degree of fineness; X, a quality of gauze rather
coarser; and Y, a quality still coarser; and Q, a quality coarser than Y. The
grain or other substance which has been pulverized in the mill enters the
apparatus for dressing or bolting at the aperture V, Figure 5, Sheet 11. The
spiral brush revolves on its axis, and forces the finest flour or other substance
through the finest wire gauze W. The bristles forming the brush, it will be
seen, are placed in a spiral direction, so that by its revolution the particles
to be dressed or bolted are carried forward, as well as forced through the aper-
tures in the gauze; another portion of the pulverized substance is forced by the
rotation of the brush through the wire gauze X, and another portion through
the wire gauze Y, and the different qualities finally escape from the apparatus
at the holes W, X, Y, into suitable receptacles; the coarse or refuse part of
the pulverized substance is carried over the gauze Y, and is discharged by the
brush at the hole Z.
Figure 6, Sheet. 11, is a transverse section of one end of the dressing
or bolting apparatus.
Sheet 12, Figure 1, is a plan of the dressing or bolting apparatus exhibited
on Sheet 11, Figures 1, 2, 3, 4, 5, and 6. The knobs or pegs at Figures. 1
and 2, Sheet 12, marked T, T, T, are for the purpose of suspending bags there
from, to catch and contain the different qualities of the substance which has
been dressed or bolted.
Sheets 13, 14, 15, 16, 17, and 18, shewing the dressing and bolting appa-
ratus rather differently constructed, although on the same principle as the one
shewn on Sheets 11 and 12. It must be understood that, for the purpose of
greater clearness of description, the dressing or bolting apparatus is shewn
detached from the mill; and its position, when attached to the mill, is indi-
cated by dotted lines, as previously described. Figure 1 (Sheet 13) is a plan
'

page_text: view of the external part of the dressing or bolting apparatus, and serves
merely as a box or case to prevent the escape of fine particles of dust.
Figure 2 is also a plan with the top of the box removed, shewing the aperture S,
where the substance enters the apparatus or trough to be dressed or bolted.
A sheet of metal covers the spiral brush, and prevents any substance from
entering the apparatus except by the aperture S. Figure 3 is a plan of the
bottom of the dressing or bolting apparatus, supposed to be turned upside
down.
Sheet 14, Figure 1, is a vertical section of the box or case in which the
dressing or bolting apparatus works, and shewing also the different compart-
ments for receiving the different qualities of the substance which has been
dressed or bolted. The compartment W receives the finest quality; the com-
partment X a quality a little coarser; Y receives a quality still coarser; and Z
is an aperture leading to a drawer which receives the refuse which is too large
to pass through the wire gauze. Figure 2 is a transverse section of the same
box or case. Figure 3, Sheet 14, is a front elevation of the box or case for
containing the apparatus for dressing or bolting; and Figure 4 is a side
clevation of the same box or case.
Sheet 15, Figures 1, 2, 3, shew the box or case with the dressing or bolting
apparatus removed.
Sheet 16, Figure 1, is an elevation of the
elevation of the same; and Figure 3, a plan.
the spiral brush is shewn on Sheet 16, at
been previously described.
spiral brush; Figure 2, an end
The iron plate which covers
Figures 4, 5, and 6: its use has
Sheet 17, Figure 1, is a plan of the wire gauze trough, in which the spiral
brush revolves; Figure 2 is a side elevation of Figure 1; Figure 3 is an end
elevation of Figure 2; and Figure 4 is a plan of the wire trough turned upside
down.
Sheet 18, Figure 1, is a vertical section through the center of the dressing
or bolting apparatus, shewing the external box or case, the wire gauze trough,
and the spiral brush; Figure 2 is a transverse section of the same; Figure 3
a front elevation of the external-box-in-case, with the dressing or bolting appa
ratus in its place; and Figure 4 is a side elevation of Figure 3.
Though we have shewn the wire trough as composed of wire gauze of three
distinct qualities or sizes of the apertures, it must be understood that the coarse
ness or fineness of the wire gauze trough must vary according as the substance
to be dressed or bolted is required in a coarser or finer state of comminution
or the wire gauze trough may be composed of wire lattice, having apertures o
holes of one uniform size. Instead of working the dressing or bolting apparatus

page_text: by a band or gut, it may be worked by wheel-work; and the connexion
between the mill and the dressing apparatus may be made by level wheels
below the grinding plates or surfaces; and in this latter case the box or case
containing the dressing or bolting apparatus may be placed at right angles to
the position shewn on Sheets 1, 2, 3, and 4, and in this latter case the dressing
or bolting apparatus may be increased in length without increasing the width
of the framing of the mill.
Throughout all the Drawings, the same letter indicates the same or similar
parts of the apparatus.
Having now described generally our Improvements in Mills for Reducing
Grain and other Substances to a Pulverized State, and in the Apparatus for
Dressing or Bolting Pulverized Substances, we proceed to describe more parti-
cularly what we claim as of our Invention.
We claim, firstly, the method of constructing grinding surfaces or plates (as
mentioned in the first part of this our Specification) with a plain or smooth
portion, in addition to the usual or grinding surface of the plate. The use of
the plain part surrounding the grinding part is to prevent injury to the grind-
ing surfaces of the plates by their being set too close together; and this plain
portion of the grinding plates serves also to rub and comminute the substances
which have not been sufficiently ground.
We also claim the exclusive use of grinding surfaces or plates formed of
carthenware or porcelain; but we prefer the grinding surfaces or plates formed.
from similar materials to those used in fabricating the mortars well-known
as Wedgwood's Mortars, and which are in common use. The peculiar
combination of materials of which the Berlin ware is composed also answers
extremely well when formed into grinding surfaces, and we claim the exclu-
sive use of grinding plates formed from such like materials. Metal grinding
plates oxydize, and then give a bad colour to those substances which are
ground between them; they are therefore not adapted to grind salts which
deliquesce, or loaf sugar; while the plates formed from the porcelaineus
earths are not acted upon chemically, and have sufficient strength of
cohesion to withstand the operation of grinding. We claim the employment
of such materials, in constructing large or small stones, in lieu of French
burrs.
And, secondly, we claim as our improvement in apparatus for dressing
or bolting pulverized substances the use of a spiral brush, which, while it
forces the pulverized substances through the interstices of the wire gauze
trough in which it works, at the same time conveys or forces the sub-
stance to be dressed or bolted over the upper surface of the wire gauze

page_text: trough, or forces it through the interstices of the gauze, thus obviating the
necessity for placing the bolting or dressing apparatus in an inclined position.
We claim the dressing and bolting apparatus constructed with a spiral
brush, whether in combination with a mill or used as a separate apparatus.
cot our hands and suals the day
AND BE IT REMEMBERED, that on the Twenty-third day of March, in
the fourth year of the reign of Her Majesty Queen Victoria, the said
Alexander Dean and Evan Evans came before our said Lady the Queen in
Her Chancery, and acknowledged the Instrument aforesaid, and all and every
thing therein contained and specified, in form above written. And also the
Instrument aforesaid was stamped according to the tenor of the Statute made
in the fifty-fifth year of the reign of His late Majesty King George the Third.
Inrolled the Twenty-fourth day of March, One thousand eight hundred
and forty-one.