Improvements in Sifting and Sorting Apparatus.
Year: 1893

page_text: Date of Application, 22nd July, 1893-Accepted, 16th Sept., 1893
Improvements in Sifting and Sorting Apparatus.
I, CARL HERMANN ALBERT STITZ, of 33 Grosse Steinstrasse, Halle-on-the--
Saale, in the Empire of Germany, Manufacturer, 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 :-
My invention relates to apparatus for sifting and sorting granular and pulverulent
materials.
In the accompanying drawing,
Figure 1 shows a longitudinal section of the improved sifting and sorting
apparatus, and
Figures 2 and 3 are plans of the same.
This sifting and sorting apparatus comprises a blower, the pipe a, the sifting
surface b and a dust chamber c. The sifting surface constitutes a box made in
the form of an isosceles triangle and closed on all sides; the pipe a for the admission
of the material to be sifted terminates at the apex of this triangle, and the sifting
surface is hermetically joined to the dust chamber.
The material to be sifted is introduced into the hopper d and thence passes into
the pipe a in which it is forced by a powerful current of air to the inclined sifting
surfaces b. In the sifting surface are provided outlet openings bounded by arcs of
circles, which openings lead to sacks adapted to be closed. The centres of the arcs.
of circles which bound the outlet openings are all in the axis or the centre line of
the sifting surface forming an isosceles triangle, and are at gradually increasing
distances from the apex of this sifting surface. For instance the first outlet
opening may be obtained by taking the centre on the centre line of the sifting
surface at a distance of metre from the apex and describing a circle with a radius.
of metre, the portion of the circle which falls on the sifting surface bounding the
first outlet. The second outlet opening is found by taking the centre on the centre
line at a distance of 1 metre from the apex of the sifting surface, and describing a
circle with a radius of 1 metre, the portion of the circle which falls on the sifting
surface bounding the second outlet.
The third, fourth, fifth and sixth outlets are found by taking the centres from
the said apex at distances of 1.5 metres, 2 metres, 2.5 metres and 3 metres and
describing circles with radii of 1.5 metres, 2 metres, 2-5 metres and 3 metres, the
portions of circles which fall on the sifting surface bounding the outlet openings.
According to the sorts to be obtained and the quantity of the material to be sifted
the dimensions of the apparatus and of the outlet openings are determined on the
aforesaid principles. The material introduced by means of air under pressure
allows its coarse portions to drop through the outlets placed nearest to the apex of
the sifting surface and its finer portions through the outlets farther away, while
only fine material or dust will pass into the dust chamber.
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
An apparatus for sifting and sorting granular and pulverulent material, in which
such material is distributed by manns of a blower in a alased and co unan
an

page_text: upwardly inclined surface forming an isosceles triangle and having outlet openings
bounded by ares of circles, and is separated at the same time.
Dated this 22nd day of July 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.