IMPROVEMENTS IN MACHINES "
Year: 1873

page_text: LETTERS PATENT to Edmond Nicolas Lacroix, of Minneapolis, in the
County of Hennepin, and State of Minnesota, United States of
America, Machinist, for the Invention of "IMPROVEMENTS IN MACHINES
"
PROVISIONAL SPECIFICATION left by the said Edmond Nicolas
Lacroix at the Office of the Commissioners of Patents, with his
Petition, on the 27th March 1873.
I, EDMOND NICOLAS LACROIX, of Minneapolis, in the County of
Hennepin, and State of Minnesota, United States of America, Machinist,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN MACHINES FOR SEPARATING AND PURIFYING MIDDLINGS," to be as follows:-
My Invention has for its objects the removal from middlings of the
fine bran and fibrous matters, which are carried off by a suction fan
above, and the separation therefrom of the fine flour, which falls below;

page_text: and also the proper grading of the middlings for re-grinding, all as
herein-after described.
A suitable frame is employed, in which are mounted a number of
reciprocating separators covered at their bottoms by bolt cloths for the
sifting of the middlings. I place a series of these separators side by
side in the same direction in the machine, while a single one above
crosses the others at right angles, and inclined chutes with flexible
connections beneath convey the siftings from the upper separator to the
lower ones. Above the upper separator are situated two hoppers with
suitable slides lying transversely which supply the material to the upper
separator, the first one being for the entrance of what is called "returns,"
while the last is for the entrance of the middlings proper. Beneath the
first hopper are two rollers and an endless belt, and beneath the last one
is a single roller. These are for the purpose of spreading the material
and delivering it properly on the upper separator. The material passing
over this primary separator is sifted through on the others lying below,
and thereby graded according to the degree of fineness; and in passing
over the lower series of separators the flour is sifted and dropped into
conveyor boxes below the lower separators, and thence conveyed away
by screw conveyors, thereby leaving the middlings in condition for being
re-ground. Beneath the conveyors are slides which are operated by
-
cords to cover or uncover passages for the escape of the flour.
J
Beneath the separators are devices which travel transversely to the
separators and in close proximity thereto, for the purpose of clearing
the meshes of the bolt cloths and keeping them free from clogging.
Brushes or air tubes may be used for this purpose. They are mounted
on screws, chains, or the like, whereby a reciprocating movement is
attained.
When brushes are employed they are made to rotate by friction wheels.
When air tubes are employed they extend the length of the separators,
and are made with enlarged bodies and contracted tops with narrow
longitudinal slits or openings in the tops which allow the passage of -air
in a thin sheet to act upon the meshes of the bolt cloths. The air tubes
receive their air by flexible or other suitable pipes at their ends, con-
necting with tubes extending to a blower, fan, or other device by which
a blast is produced.
If single-threaded screws are employed for driving the brushes or air
tubes two bevil gear wheels with a sliding clutch and a weighted lever

page_text: between are used for changing the motion of the screws at the end of
the stroke. This apparatus is connected by arms and levers with a loose
rod having stops thereon, over which rod rests a fork attached to the
under side of the brush or air tube.
If double-threaded screws are used the threads cross each other
reversely, and at the end of the stroke the brushes or air tubes turn back
without reversing the screws..
If endless chains are employed they pass round pulleys, and have a
pin which fits in a loop on the bottom of the brushes or air tubes, and
gives a reverse movement by a constant turning..
On the top the machine has an exhaust dome covering all the com-.
partments of the separators, and communicating therewith by suitable-
passages covered by slides. On this exhaust dome is a fan case wherein
is a fan having wings curved backward from the direction of its rotation.
This fan draws up all the fine impurities, bran, and light fibrous pellicles
from the middlings, and discharges them through the spout of the fan
case. Suitable air passages connecting with the separator compartments
may be used in place of the exhaust dome. The separator compart-
ments beneath the dome have shelves or partitions with suitable air
passages, the object of which is to equalize the action of the draft in
passing up to the exhaust dome.
-
The separators receive their motion by means of adjustable eccentrics
mounted on shafts, and so fitted. that they may be turned to different
positions and fixed in place, and arranged to give any desired amount of
vibrating motion to the, separators. The separators are also mounted on
eccentrics or equivalent devices having straps attached thereto and con-
necting with the bottom of the separators, and arranged to produce a
vertical rocking motion in combination with the horizontal motion.
The gearing and belting of the machine may be arranged in any.
desired manner to give the proper motion to the parts.,.

page_text: SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, and of an Order of the Lord Chancellor, by the said Edmond
Nicolas Lacroix in the Great Seal Patent Office on the 11th October
1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDMOND
NICOLAS LACROIX, of Minneapolis, in the County of Hennepin, and
State of Minnesota, United States of America, Machinist, send
greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Twenty-seventh day of March, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Edmond Nicolas Lacroix, Her special
licence that I, the said Edmond Nicolas Lacroix, my exécutors, ad-
ministrators, and assigns, or such others as I, the said Edmond Nicolas
Lacroix, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain, and Ireland, the Channel Islands, and the Isle of Man, an In-
vention for "IMPROVEMENTS IN MACHINES FOR SEPARATING AND PURIFYING
MIDDLINGS," upon the condition (amongst others) that I, the said Edmond
Nicolas Lacroix, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office, on or before the Fourteenth

page_text: In the Drawings, Fig. 1 is a plan of the machine; Fig. 2 is a vertical
section in line x, x, Fig. 1; Fig. 3 is a vertical section in line y, y,
Fig. 1; Figs. 4, 5, 6, 7, 8, 9, 10, and 11 are detail views.
A represents the casing, which may be of any desired size or form,
B, B, B, are three longitudinal screens of rectangular form lying side
by side in seperate chambers of the casing; C is a cross screen resting
above the others, and lying at right angles over their heads. The
siftings from this cross screen fall upon the heads of the longitudinal
screens where they are subjected to a re-screening in their passage over
the latter.
a, a, are inclined chutes or plates attached to the heads of the longi-
tudinal screens and extending up under the cross screen in a diagonal
position, having flexible connections 6 to prevent passage of the
middlings and air around the chutes. These chutes serve simply to
conduct the middlings properly on the heads of the longitudinal screens
as they are sifted through the cross screen. D, E, are two hoppers
resting over the head of the cross screen, and employed for feeding the
middlings and returns into the machine. Beneath the hopper D are
two rollers and a belt c; and beneath the hopper E is a single roller d.
These devices are for the purpose of feeding the middlings and "returns"
in a thin and uniform sheet to the screen. The hoppers are provided
with slides f, f, by which the flow of the material may be properly
gauged. F, F, F, are conveyors made in the form of screws and resting
in conveyor boxes, G, G, G, which lie directly beneath the screens
B, B, B. These conveyors carry the material as it is sifted through to
the discharge opening g, where it is discharged. h, h, are openings
through the sides of the conveyor boxes for the purpose of allowing
entrance of air under the centre of the screens. i, i, are stationary
boards;
and j, slides, beneath the conveyor boxes. k, k, are cords
attached to the slides j, and passing around a pulley 7, by which means
the slides are operated. H is an exhaust dome situated over the screen
chambers and connecting therewith through ports m, m, which are
provided with slides n, n. I is a fan case; and K, an exhaust fan, located
over and partially within the dome. The wings of the exhaust fan are
curved opposite to their motion, as shown in Fig. 2, the object of which
is to produce a regular and uniform draught. The exhaust is for the
purpose of drawing off and discharging the light bran, fibrous matters,
and impurities which rise from the middlings, which effect is accom-

page_text: :
plished by the draught through the screen chambers above the screens.
ọ, o, are shelves arranged in the screen. chambers for the purpose of
giving an indirect passage to the draught and modifying the exhaust.
L, L, are air tubes beneath the screens for the purpose of blowing
through the screens, thereby keeping the meshes clear and raising the
fibrous matters so that they may be drawn off by the exhaust. These
tubes are made preferably enlarged at the bottom, as shown at h¹, and
contracted at the top as shown at i, and a narrow slit ¹ is made at the
top extending the whole length to allow the air to pass. The tubes
might be made of other form and perforated instead of slitted. These
tubes extend the whole length of the screens, and may be made either
stationary or movable:. In the latter case they may receive motion by
any desired means.
I prefer a double threaded screw S, as shown in Fig. 4, the threads
of said screw being arranged reversely to each other, so that when the
tube has passed to the extent of its stroke over one thread it shifts
automatically by a suitable shifting device and goes back over the other
thread, the screw turning in the same direction all the time. The screw
S may be connected with only one of the air tubes beneath the screens
B, B, and this air tube may be connected with the others. by rods or
other attachments.
Instead of the double threaded screw two or more single threaded
screws may be employed, said screws being connected by suitable
counter shafts and bevel gears, and one of them having a shifting clutch,
as shown in Figs. 6 and 7, this arrangement consists of a bevel gear p,
on the end of the screw, and two loose bevel pinions q, q, on a counter-
shaft. A sliding clutch head r. rests on the countershaft between
them, and with this is connected a lever & having a weight t at the
top. The lower end of the lever has a slot which fits over a bolt u. The
lever is also connected with an elbow v, pivoted to the frame of the
machine, being bent down so as to attach at its lower end to a sliding
rod M, which. rests under the screen. The rod has two. stops w, w, and
the air tube has a forked arm x, Fig. 8, which embraces the rod. At the
extent of each stroke of the air tube the forked arm strikes the stop w,
thereby sliding the rod endwise, and acting upon the elbow so as to shift
the clutch head r from one pinion q to the other.. By throwing the
lever at the end of the reverse stroke the same action takes place, the
weighted lever being thrown over automatically by each movement, and.

page_text: the screw consequently reversed.
Various other methods might be
employed for moving the air tubes in an equivalent manner. With one
end of each air tube is connected a flexible tube N attached to a wind
trunk O. The wind trunk is connected by a pipe P with an ordinary
blower, fan, or equivalent device Q, by which the blast is produced.
The flexible tube allows the necessary reciprocations of the air tube,
while a constant current of air is blown through the narrow slit in the
top of the air tube and forced through the meshes of the screen.
:
In some instances a longitudinal brush, as shown in Fig. 10, or a
rotary brush, as shown in Fig. 11, might be employed. A motion. is
given to the brush crosswise of the screen. Where the rotary brush is
employed a traction wheel y is employed running upon a fixed way.z
to produce the proper rotation. The brush is driven by the double
thread screw before described.
:
-
-
The screens are hung upon eccentrics a³, a¹, and connected therewith
by reverse straps 6', 6', as shown in Fig. 5. By this means as the
screens reciprocate the eccentrics turn and cause a compound horizontal
and vertical rocking motion of the screens, which agitates the middlings
spread thereon, and equally diffuses them over the whole surface.
Instead of the above-described arrangement hangers may be employed
for sustaining the screens.
The screens receive motion by double eccentrics R, R, resting on
shafts and playing between rocker plates c², c³, to which the screens are
attached. Each of the eccentrics R consists of an interior eccentric d
made fast to the shaft, and an exterior eccentric f¹ which is adjustable
upon the interior one, and is made fast thereon at any given position by
a key g. By changing the position of the exterior upon the interior
eccentric the throw of the screen may be changed more or less at
pleasure.
What I claim and desire to secure by Letters Patent is,―
1st. In a middlings separator and purifyer I claim the combination
with the series of longitudinal screens B, B, B, of the cross screen C
lying at right angles to the others when arranged to operate in the
manner and for the purpose specified.
2d. In a middlings seperator and purifyer I claim in combination
with a screen on which the middlings are received, and with an exbaust

page_text: which draws off the fine fibrous matters and impurities, an air tube or
tubes located under the screen or screens, and an independent air blower
connecting with said tube or tubes, and so arranged as to clear the
meshes of the screens by.currents or jets from said tube or tubes, sub-
stantially as specified.
3d. I claim the combination of the air tube or tubes L with the
screens when said air tube or tubes are made to travel beneath the
screens, and so arranged as to concentrate the blast and force it through
the meshes in a thin line, substantially as and for the purpose specified.
4th. I claim the construction of the air tubes L with the enlarged
body h¹, contracted top i, and narrow slit or opening extending longi-
tudinally of the tubes, as and for the purpose specified.
5th. I claim in combination with the travelling air tube or tubes L
the flexible tube or tubes N, and a blower, fan, or equivalent device.
Q, for forcing air through the air tube or tubes, as described.
6th. I claim in combination with the travelling air tube L, or a
travelling brush, the double threaded screw S, as and for the purpose
specified.
7th. I claim in combination with the screens the eccentric a³, a¹, and
straps 6', 6', for producing a compound horizontal and vertical motion of
the screens, as and for the purpose specified...
8th. I claim in combination with the screens the double eccentric R
consisting of the fixed interior eccentric & and adjustable exterior
eccentric f¹, as and for the purpose specified.
In witness whereof, I, Edmond Nicolas Lacroix, have hereunto set
my hand and seal, this Twenty-third day of August in the year of
our Lord 1873.
EDMOND NICOLAS LACROIX. `(L.S.)