Improvements in or appertaining to Machines applicable for Separating Dust or like Particles from Air or other Gases, or Dust or Sand from the Mixture of Cotton and Air from Scutching Machines, or for other similar uses.
Year: 1892

page_text: Date of Application, 28th Nov., 1892
Complete Specification Left, 13th Sept., 1893-Accepted, 25th Nov., 1893
.
PROVISIONAL SPECIFICATION.
Improvements in or appertaining to Machines applicable for
Separating Dust or like Particles from Air or other Gases,
or Dust or Sand from the Mixture of Cotton and Air from
Scutching Machines, or for other similar uses.
I, PIETER VAN GELDER, of Sowerby Bridge, in the County of York, Milling
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention has for its object the improvement of that class of dust collectors
known as vortex machines of which my three Patents Nos. 200308, 1811" and
93981 are a type.
These machines in common with nearly all other dust collectors simply separate
the dust without grading it. This is mainly owing to the conical or pyramidal
form of the lower part of the chamber which brings all the material down to one
opening. Now my present invention is designed to not merely separate the dust
but to grade it as well and also to tear up any large lumps of light floculent
material that may enter the machine. One of the main improvements of this new
machine consists in using a flat or practically flat bottom instead of a hopper.
Another consists in having two orifices or sets of orifices for dust in the bottom
instead of one as heretofore. A third improvement consists in placing low vertical
ridges in the volute form on the bottom of the chamber to enable the wind and the
impurities of the dust, to bring the latter to the centre. On these ridges I prefer
to place sharp pins projecting upwards not vertically but inclined somewhat in the
direction in which the wind passes in its vortical action. Another improvement
consists in making the exit spout rectangular instead of round, or if it be cylindrical
having one or more embayments at the side. The object of this is that in these
machines there is nearly always a strong up current and this hinders the dust from
descending. This current however is vortical and hence does not touch to any
material extent the corners. The result is if the exit spout be made angular the
dust flows down these angles. Of course I am well aware that rectangular spouts
have long been used in milling machinery but I am not aware that the dust exit
from a vortex machine has ever been formed rectangular as it has generally been
thought that the cone or pyramid should end abruptly with its truncation. Another
improvement consists in suspending a short distance above the exit of the dust a
round disc. This disc is supported on a screw or other device whereby it can be
raised and lowered and thus its exact best position for the particular material or
speed used, regulated. In my experimental machine I have made the disc the
same size as the air exit orifice above and this happens to be one third of the
internal diameter of the twelve sided prism forming the chamber. I have found
that the actual form of the chamber is comparatively immaterial. It can be either
conical inversely conical, cylindrical pear shaped or a spheroid or be any of these
shapes modified by forming its horizontal section polygonal instead of round, but
after trying nearly all these forms I have found that a twelve sided prism gives
apparently the best results, the exit orifice being a six or eight sided truncated
inverted cone. The entrance for air as in all these machines is tangential or in
line with one of the sides of the polygon and is in the upper part of the side. In
using this machine for taking the mixture of cotton and air from a scutching
machine, large lumps of cotton pass over the ribs at the bottom but the pins tear
off small pieces of cotton, off them, as they pass, and this continues until the lump
of cotton is so small that it will be stopped by the volute ridge. It then passes
along the volute ridge to the central hole and falls down. Besides cotton however

page_text: dust sand, cotton-seed and dirt pass in large quantities into this machine. In order
to separate these I have either the entire bottom or all that part near the periphery
perforated with holes large enough for the impurities to pass through. I also
pierce the bottom close to the central spout with holes. One or more hopper
devices can be placed below the bottom to collect these materials and the holes in
the bottom if desired can be graded so that sand and dirt will fall out of the outer
portion and cotton-seed and larger lumps nearer the centre. The hopper is so
arranged however that there shall be a slight vortical motion of the air therein.
The result is that there is a constant slight indraft at the outside to carry the dust
and dirt down and an exit draft through the holes immediately surrounding the
exit, for cotton. I find in this way that cotton which enters the machine full of
sand, dirt and seeds, escapes from it in a white flaky form. In my experiments I
have found that two spiral ribs making about a circle and a half at equal distance
from each other give very good results. They are not strictly volutes but are
closer together as they near the centre; my experiments on this head however are
not finished. Another improvement which I have found very useful is to form the
bottom inch or two of the polygonal chamber absolutely circular. The reasons of
these appears to be, as the dust which is separated in the corners, descends these if
there be no circular cone at the bottom it forms a lump at each corner which is
rather difficult for the air to remove. If however the bottom inch or so of the
chamber by cylindrical with the diameter equal to the diagonal of the polygon,
there is no angle at this point for the dust to collect in, but the wind takes a
circular course and at once sweeps all the dirt round with it until caught by the
volute ribs. In other respects the present invention resembles that set forth in my
Patent No. 181191. I have not however tried this machine to see whether com-
pounding it by placing another on the top, is advantageous; it separates dust
however so extremely well that there seems little liklihood of need for it.
Dated the 26th day of November 1892.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or appertaining to Machines applicable for
Separating Dust or like Particles from Air or other Gases,
or Dust or Sand from the Mixture of Cotton and Air from
Scutching Machines, or for other similar uses.
I, PIETER VAN GELDER of Sowerby Bridge, in the County of York, Milling
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:-
This invention has for its object the improvement of that class of dust collectors
known as vortex machines, of which my three Patents Nos. 2003089, 181191
and 9398 are a type. Most of these machines in common with nearly all dust
collectors simply separate the dust without grading it. This is mainly owing to the
conical or pyramidal form of the lower part of the chamber which brings all the
materials down to one opening.
Now my present invention is designed in part to not merely separate the dust
but to grade it as well, also to tear up any large lumps of flocculent material that
may enter the machine.
The invention is best described by aid of the accompanying drawings, in
which :-
Figure 1 is a vertical section of my apparatus :
Figure 2. a sectional plan ·

page_text: !D these
It
A, is a prismatic chamber preferably in depth about of the diameter.
could, however, be cylindrical, slightly conical, oval with flat top and bottom, or
other like shape. I prefer, however, a prism with twelve sides. B is a small
portion of the depth turned cylindrically: C, entrance for air which is made
parallel to one of the sides. If, however, instead of a prismatic chamber, there is
a cylindrical chamber, it is made tangential thereto. D is a pyramidal exit,
preferably extending about halfway to the bottom of the chamber; it should have
a slightly larger area in its narrowest diameter than the cross sectional area of C.
E is the bottom of the chamber which is flat as shown and preferably perforated,
and which has to be perforated if the dust is to be graded. F are a series of
curved ribs placed on the bottom guiding the dust to the central opening G. G is
the dust opening which can be trapped or not as desired. H H' are holes in the
bottom. These, if desirable, can be of two or more sizes, each size being arranged
in a circular zone, the smallest being nearest the outside; the size of these holes
depends upon the material to be separated. Another series of holes, preferably in
the form of narrow vertical slits, can be made, if desired, in the purely cylindrical
portion of the chamber, but, as a rule, holes in the bottom will be found sufficient.
Where the machine is only used for separating dust from air, and not for grading
the dust at all, neither of the holes H or H are used. is a series of spikes placed
on top of the ribs; these spikes point slightly outward at an angle say of 60 degrees
from the horizontal. I is a plate on screwed shaft J, which can be raised and
lowered as desired by means of hand wheel j, and is preferably the same diameter
as the bottom of exit for air, D. This plate is used when the opening G is not
trapped in order to prevent a direct through current. M and M are two hoppers
used when the machine is employed for grading, but not required if there, be no
holes H H'.
I will now describe the mode of action as applied to separating air, dust, and
cotton which escape from a scutching machine. These are passed in by means of
the blast through the spout C, and, whirling round the dust and cotton, fly to the
outside, whereas the purified air passes up through D. Falling down the sides, the
dust and cotton are guided by the ribs F, which can be more numerous if desired
than those shown in the drawings. I find, however, for most purposes, two ribs are
best, as shown. The large lumps of cotton pass over these ribs and get torn up to
some extent by means of the spikes f. They continue revolving round the machine
until sufficiently torn up to be guided by the ribs F to the spout G, the dust being
smaller flies out through the holes H and H, and, if the outer holes H are of small
diameter while the inner holes H' nearest Ġ are of large diameter, the dust will
fall out into bopper M' and the cotton seed into hopper M, whereas the cotton
itself will only fall into the spout G where it comes out clean from both dust and
cotton seed.
The advantage of this apparatus, for even cleaning air from dust, over the
tapering machines hitherto used is very great. I find that it is not desirable for the
air to go more than twice round the machine before rising from the bottom, as
the great friction on the side comminutes the dust still more. Where, however, in
a tapering machine, the dust goes round eight or nine times, the dust is very
comminuted and becomes so fine that it gets absorbed by the air and escapes with
the effluent air. I find, too, that by allowing the air only to go round once or twice,
the back pressure on the fan is much less at a given speed of fan, consequently, more
air is passed through with less power.
Although I have only shown the sides vertical, they may be somewhat inclined
in either direction, or curved to some extent without injuring the effect of the
machine.
Since filing my Provisional Specification, I have very considerably improved
upon my invention in various ways. The entire invention is set forth in this and
in Specifications Nos. 212182 and 22919" filed at the same time with this. I have

page_text: set forth some of the improvements covered by No. 22919 of 1892 in this Specifi-
cation in order to fulfil the law which requires the inventor to show the best mode
known to him of carrying his invention into effect, but as these points were not set
forth in my Provisional they are not claimed in this Specification but are claimed
in the succeeding one.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is―
1. In a dust collector, a round or polygonal separating chamber in which the
dust laden air forms a vortex or whirling body, and which is provided with a
discharge opening for the purified air above, a discharge opening for the separated
dust below and a substantially flat floor provided with guiding ribs for guiding the
dust to the dust opening.
2. A dust collector composed of a separating chamber not tapering downwards
having a tangential air inlet C, a discharge opening D at top for the purified air, a
discharge opening G at bottom for the dust and guiding ribs on flat bottom for
guiding the dust to the central orifice G.
3. The improvement in separating dust from the mixture of cotton and air from
scutching machines and other like uses, which consists in passing the whole through
a vortex machine in which there are devices for tearing up the cotton, said vortex
machine having perforations for the dust over which the air and cotton pass before
they reach the discharge orifice for the cotton.
4. In combination with a vortex machine for separating dust from air, a series of
perforations of different sizes in or near the floor of the chamber for separating the
solid matter from the air, and at the same time grading the same, substantially as
described.
5. In combination with a polygonal dust collecting chamber, a circular portion at
the very bottom, substantially as and for the purposes described.
6. In combination with a cylindrical or prismatic vortex machine substantially as
described, the adjustable baffle plate and the angular exit in a flat floor, each
substantially as and for the purposes described.
Dated this 12th day of September 1893.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.