IMPROVEMENTS IN MACHINERY FOR SEPARATING LIGHT SOLID PARTICLES FROM AIR ESCAPING FROM MIDDLINGS PURIFIERS, GRINDING STONES, OR OTHER MACHINERY
Year: 1881

page_text: LETTERS PATENT to Louis Fiechter, of Minneapolis, in the State of Minnesota,
but temporarily at the Office for Patents, 0, Lord Street, Liverpool, in the
County of Lancaster, for an Invention of "IMPROVEMENTS IN MACHINERY
FOR SEPARATING LIGHT SOLID PARTICLES FROM AIR ESCAPING FROM
MIDDLINGS PURIFIERS, GRINDING STONES, OR OTHER MACHINERY." A com-
munication from abroad from the Firm of Christian Brothers and Company,
of Minneapolis aforesaid.
"
PROVISIONAL SPECIFICATION left by the said Louis Fiechter at the Office
of the Commissioners of Patents on the 4th May 1881.
LOUIS FIECHTER, of Minneapolis, in the State of Minnesota, but temporarily
at the Office for Patents, 6, Lord Street, Liverpool, in the County of Lancaster.
IMPROVEMENTS IN MACHINERY FOR SEPARATING LIGHT SOLID PARTICLES FROM
AIR ESCAPING FROM MIDDLINGS PURIFIERS, GRINDING STONES, OR OTHER
MACHINERY." A communication from abroad from the Firm of Christian
Brothers and Company, of Minneapolis aforesaid.
In the various machines for converting grain into meal or flour and other
substances a blast or suction is frequently used to carry off the light particles.
The air and containing particles form an explosive mixture, and numerous mills
have been burnt down from this cause. The usual method of purifying the air is
to pass it to the "stive room" and let the stive settle.
Now this Invention is designed to avoid the necessity of a stive room by
purifying the air and collecting the stive and other light particles by means of a
small machine. This machine consists of a skeleton drum covered with woollen
or other cloth with a heavy nap. This cloth instead of being wound round the
drum is made to zigzag in and out round two circles of fingers alternately, so as
to look like a toothed wheel with very deep sharp teeth. This drum revolves in a
casing, into which at a tangent the air is driven in such manner that it is driven
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against the teeth" of the revolving drum, the space between the teeth and the
casing becoming smaller and smaller till it is reduced to zero after travelling about
three quarters round the drum. Beyond this point vertically below the drum is a
spout the width of the drum, with a segment of the casing on each side closely
fitting the ends of the teeth of the drum, the ends being. preferably armed on the
front edges with india-rubber wipers, and the casing with stout felt or cloth, so as
to entirely exclude the unfiltered air from the spout. At the air entrance to the
casing a plate or deflector is placed to deflect the more solid particles into a pocket
or side chamber. This chamber can be connected with the spout by an automatic
valve, which yields and allows the stuff to pass when the accumulation reaches a
given weight.
In the spout is fixed one or more knockers. These knockers are arranged by
gearing to work synchronously with the drum, and as cach tooth comes to a given
point immediately over the spout to fly out and strike it, and thus by the
consequent vibration cause all the particles sticking to the cloth to fall down into
the spout. One way of actuating this knocker is as follows:-A cam on the
shaft gradually draws back the knocker by bearing against a pin on it; as the
end of the cam leaves the pin a spring causes the knocker to fly back and strike
the tooth, the hind edge of the tooth being preferably shielded with metal to take
the blow.
The mode of action is as follows:-The air loaded with stive or other mechanical
impurities enters the casing at a pressure rather greater than that in the interior
of the drum. The larger particles striking the deflector are thrown into the side
pocket. The air with remaining impurities goes round the casing, and unable to
otherwise escape it passes through the cloth, leaving its impurities behind on the
surface; as the teeth of the drum in turn come over the centre of the spout the
knocker strikes them, and shakes off the stive or other particles thereon into the
spout. The purified air escapes at the ends of the drum.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent (and
of an Order of the Lord Chancellor) filed by the said Louis Fiechter in the
Great Seal Patent Office on the 3rd December 1881.
(f
LOUIS FIECHTER, of Minneapolis, in the State of Minnesota, but temporarily
at the Office for Patents, 6, Lord Street, Liverpool, in the County of Lancaster.
IMPROVEMENTS IN MACHINERY FOR SEPARATING LIGHT SOLID PARTICLES FROM
AIR ESCAPING FROM MIDDLINGS PURIFIERS, GRINDING STONES, OR
MACHINERY." A communication from abroad from the Firm of Christian
Brothers and Company, of Minneapolis aforesaid.
OTHER
In the various machines for converting grain into meal or flour and other
substances a blast or suction is frequently used to carry off the light particles.
The air and such particles form an explosive mixture, and numerous mills have.
been burnt down from this cause. The usual method of purifying the air is to
pass it to the "stive room" and let the stive settle.
Now this Invention is designed to avoid the necessity of a stive room by
purifying the air and collecting the stive and other light particles by means of a
small machine.
This machine is best described by aid of the accompanying Drawings, in which
Fig. 1 is a transverse, section, and Fig. 2 a longitudinal one. In these A is a
cylinder of woollen cloth with a thick heavy nap wound in zig-zag manner over a
skeleton frame of wood or other material, as shewn (s); C, an eddy chamber or
pocket to receive heavy particles; D, air arrester or baffle plate; E, E, knocking
apparatus; H, main delivery spout for stive and dust; L', a cam on driving shaft
drawing back the knocker or hammer K once at each revolution by coming in
contact with the pin M on same, and thus compressing the spring R until the cam
passing the pin the knocker is free to bound back and strike a corner on the
cylinder, as shown. The other letters of reference will be explained further on.
The mode of action is as follows:-The driving shaft being driven at about
thirty revolutions a minute, and the air being blown into the casing B, it is unable
to escape except through the cloth of cylinder A; it therefore forces its way
through the cloth and out at the ends, leaving the stive and other solid impurities
on the surface of the cloth. Some of the heaviest impurities however striking
against the baffle plate D rebound, and are caught in the pocket C, whence they
can be removed by a separate spout at intervals or by a spring-door or counter-
weighted valve V arranged to open when a given weight is pressing against it.
The pocket can then empty intermittently into. the main delivery spout H or a
separate spout, as preferred. The air in B is prevented from entering the spout H
by a thick cloth, felt, or other padding or covering G on the air arresting boards
D', D. The air is further kept out by means of little projecting india-rubber
wipers or projecting pieces T on each of the ribs of drum A. Each of these ribs
are further armed on the other outer edge with a metal guard or plate for the
hammer K to strike against. The gearing connecting the driving shaft L with
the central shaft X is so designed that the said driving shaft shall make as many
revolutions per revolution of the central shaft as there are ribs in the central
drum A, and the action of cam L' on the (hammer) pin M is so regulated that the
hammer in flying back after the compression of the said spring shall forcibly
strike each tooth or ridge of the drum in succession as the said tooth arrives at or
about the central point over the spout H. This stroke shakes the ridge of the
drum and causes the dust and solid matters thereon to fall off onto the spout H.
Thus the air laden with impurity enters B; the air passes through the cloth P,
leaving the impurities behind, and escaping at the end of the drum at O. The
dust is filtered out and deposited in spout H.

page_text: This Invention is specially valuable for grain mills and for purifying the air
escaping from manufacturing operations, wherein it gets laden with small light
particles.
Having now described my Invention, and the best mode known to me of
carrying it into effect, I wish it to be understood that what I believe to be new
and desire to protect under the hereinbefore in part recited Letters Patent is,―
First. The mode of separating solid impurities from air by causing the air to
pass through the cuvelope of a revolving drum having a large extent of porous
surface, which surface at one part of its revolution, where it is not exposed to the
air to be cleansed, is freed by mechanical action from adherent matter which falls
into a separate receptacle.
.
Second. The apparatus for purifying air or other gas from solid impurities,
consisting of a corrugated or star shaped porous drum revolving with part of its
surface forming part of the walls of an air chamber, into which the air is forced or
drawn, the remaining part of its surface being shut off from the dusty air by
having to pass over contact surfaces.
Third. The combination with a revolving drum or its equivalent filtering air
from without inward of a knocking apparatus working synchronously with it, and
below it in such manner as to shake the undue surface of the drum, and so knock
off the dust into a receiving spout or chamber shut off and separate from the
unfiltered air chamber.
Fourth. The combination of a drum formed of cloth or other porous material
strung onto two circles of bars, so as to form a star shaped or radiating drum with
large surfaces, india rubber or other wipers and curved abutments, each of the
latter extending over such an arc as to always have at least one radiation of the
revolving drum passing over their surface.
In witness whereof, I, the said Louis Fiechter, have hereunto set my hand
and seal, this Eighteenth day of November, in the year of our Lord One
thousand eight hundred and eighty one.