Method of and Apparatus for Drying and Sifting Materials Consisting of Loose Pieces or Granules.
Year: 1887

page_text: Date of Application, 31st Oct., 1887
Specification Accepted, 2nd Dec., 1887
COMPLETE SPECIFICATION.
Method of and Apparatus for Drying and Sifting Materials Consisting
of Loose Pieces or Granules.
I, LUDWIG KASPAREK, of Graz, (Styria) Engineer, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:
According to this invention materials which consist of granules or of loose pieces,
for instance, grain, shavings of wood for the manufacture of cellulose &c are dried by
causing them to pass successively, from within outward or from without inward
through the annular spaces between concentric cylindrical sieves, the innermost ol'
which contains a perforated tube for the dispersion of dry and warmed air.
In order to propel the materials in the cylindrical sieves these latter are provided
with helical blades and are adapted to be rotated upon their axis.
Drying apparatus as briefly described above are represented upon the annexed
drawings, in which fig. 1 is the vertical longitudinal section of a drying apparatus, in
which the material is moved from without inward.
Fig. 2 is a sectional top side view of this apparatus.
Fig. 3 is a vertical cross section of the apparatus.
Fig. 4 is an end elevation of the same, partly in section.
Fig. 5 is a sectional side elevation of an apparatus adapted to move the material
from within outward.
Figs. 6 and 7 are respectively a vertical cross section and an end elevation corre-
sponding to Fig. 5.
In every case there is in the axis of the apparatus a perforated tube a for the
dispersion of air, which at the same time is the shaft for the inner cylindrical sieve or
sieves.
The tube a is supported by two bearings bb; it is closed at one end and communi-
cates at the other end by means of a stuffing box with an air pipe c, into which a
blower forces continually air heated by suitable means.
In the apparatus adapted to move the material from without inward (figs. 1-4) a
perforated cylinder d is connected to the tube a for dispersion of air, by means of a
certain number of helical blades a', fixed on the tube a so that, when the tube a is
rotated by means of its belt pulley a² the cylinder d which is open at either end partakes
of the rotation.

page_text: Beside the fixed pulley a² is arranged, as usually, the loose pulley a³.
The cylinder d is concentrically surrounded by a second perforated cylinder e which
by means of hoops, surrounding it, rests upon the rollers and e³.
The rollers on one side, are rigidly connected with their shaft which is driven
from the rotating air dispersion tube a by means of the chain wheels a' and e and a
suitable chain, while the rollers on the other side of the cylinder e are loosely
mounted upon their axes e.
In consequence of this arrangement the cylinder e revolves in the opposite direction
to cylinder d and the helical blades d' which are fixed to the outside of the cylinder d
perform the office of a feeding screw within the cylinder e.
The cylinder e loosely surrounds by its open end the cylindrical mouth ƒ³ of a
casing provided with a hopper f.
The hopper contains a feed roller f provided with blades in order to afford a con-
tinual and uniform introduction of the material to be dried into the casing or receiver f.
From the figures 2 and 4 it is to be seen, that the feed roller f is driven by the
shafte, by means of the chain wheels e' and h intermediate shaft A³, and bevil h³
and f'.
gear
From the casing the material is transported by the helical blades d' of the
cylinder d to the closed opposite end of the cylinder, from the circumference of which
a certain number of helically curved wide tubes g extend into the shorter inner
cylinder d.
In consequence of the rotation of the cylinder e tho material penetrates into the
radially arranged outer apertures gl of the tubes g and in the same measure as these
tubes rise the material advances within the same and finally falls through the other
end g into the cylinder d.
In the cylinder d the material is again propelled by the blades a' and when arrived
at the end of this cylinder, it is seized by the feeding screw a fixed upon the rotating
air dispersion tube a and conveyed into the tube i which loosely surrounds the end of
the cylinder d and extends outwards through the casing f.
The pressure of the dried material upon the weighted flap i closing an exit opening
forces the flap open, and the material falls into the hopper j
In order to allow of one and the same body of material being several times passed
through the apparatus, for the purpose of more completely drying the same a suitably
shaped cylindric slide k is arranged within the tube i, which is open at the under side,
towards the casing the said slide having a notch ke formed in its edge. As soon as
this notch is brought over the lower aperture of the tube i the material falls again
through this aperture into the casing and thence passes a second timo into the
cylinder e. In order to allow the slide k being turned as may be required it is pro-
vided with a perforated end in the shape of a wheel the nave k³ of which surrounding
the tube a extends outwards through the end of the tubo i and is provided with a
weighted reversing lover k'.
The whole apparatus is enclosed in a wooden case I provided at its upper side with
an exit tube for the air saturated with moisture. This exit tubo may be put into
communication with an exhauster. The outer cylinder e may in certain cases serve at
the same time as a sizing-drum; for which use it is to be made out of perforated sheet
metal, with conveniently large perforations, or of a wire fabric with conveniently large
meshes.
In such cases the wooden case I must be provided with outlets for the sized
material, and suitable doors for these outlets. As will be readily understood, it is more
advantageous for the rational proceeding in the drying, to propel the matorial from
without inward because in this case the material which is already dried to a certain
degree comes into contact with absolutely dry air. On the other hand, when the
material is moved in the inverse direction, it is possible to combine a greater number
of concentric sieve-cylinders, without rendering the apparatus too costly, as in this
case the material simply falls out from the end of every sieve cylinder into the next
cylinder, so that the lifting devices (tubes g) are dispensed with."
Such an apparatus is shown by figs. 5-7. In place of the cylinder sieved three

page_text: such cylinders m, n, o are connected with the tube a these cylinders being provided
on their inner surface with helical blades m², n', o alternately in the form of right
hand and left hand screw threads. The material, which is thrown into the hopper f,
falls in this case upon a feeding screw a which is mounted upon the air dispersion
tube a and propels the said material into the shortest innermost cylinder m. The
blades m', in the cylinder m propel the material through this cylinder, out of the other
end of which it falls into the next larger and longer cylinder n with the blades n',
which are curved in the reverse direction as the wings m² and so on.
From the outmost cylinder e the dried material falls into the closed hopper p and
by its own weight opens from time to time the weighted door p¹, of the saine and thus
periodically discharges itself.
Having now particularly described and ascertained the nature of this invention and
and in what manner the same is to be performed, I declare that what I claim is :
1. A method of drying materials, composed of loose pieces or granules, the said
method consisting in passing the material successively from within outward or from
without inward through annular spaces between each two of a sories of cylindrical
sieves the innermost of which contains a perforated tube emitting warm dry air.
2. In an apparatus for carrying out the method referred to in the 1st claim with
the material moving from within outward, the combination with a rotating air dis-
persion tube a of a series of concentric cylindrical sieves m no rigidly connected to
the said tube, of helical blades m¹ no fixed to the inside of the said cylinders and
forming alternately left-hand and right-hand serow-threads, and of a feeding-scrow,
which forces the material into the innermost, shortest cylinder, substantially as and
for the purposes described.
3. In an apparatus for carrying out the method referred to in the 1st claim with
the material moving from wing inward the combination with an enclosing
cylindrical sieve e of a short tubo "projecting into the said cylinder, of a casing fi
provided with a charging hopper for the material to be dried and communicating
with the said tube, of helically curved tubes 7 extending from the discharge end of
cach larger cylinder into the next smaller one, and of a feeding screw, which extracts
the dried material from the innermost sieve-cylinder, substantially as and for the
purpose described.
g
4. In apparatus of the construction set forth in the 2nd and 3rd claims, the use of
an outer sieve-cylinder e turning in the opposite direction to the inner ones and
having openings of such a size as to be adapted for sifting purposes substantially as
described.
5. In an apparatus of the construction set forth in the 4th claim a cylindrical slide k
arranged within the tube i containing the, feoding-screw a, the said slide k either
covering a communication aperture between the tube i and the casing f' in order to
cause the material to be expelled by the feeding-screw; or uncovering the said aperture
for causing the material to re-enter the onter sieve-cylinder and to pass again through
the apparatus, substantially as described.
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1007
ABEL & IMRAY,
Agents for the Applicant.