Year: 1895

page_text: Date of Application, 5th Mar., 1895
Complete Specification Left, 16th Mar., 1895-Accepted, 2nd Nov., 1895

page_text: it first descende, to a distance equal to about half the height or depth of such
compartment; then down again, and as a natural consequence of the rotary
motion of the drum, and of its momentum-is dropped in a practically vertical
direction into the following compartments of the sifting surface, situated on lower
levels.
The connection between the several compartments of the sifting surface, which
are mounted in frames e of any convenient shape or construction, is effected by
moans of fillets or bands barrauged at an angle to each other wherever two adjacent
sieve-compartmenta meet. This angle is not, as is some well-known sifting machines,
an acute angle, but an obtuse one, which, however, should but very slightly
exceed 90°. Owing to such an arrangement thero are not formed anywhere in the
sifter any corners or recesses which would be calculated to facilitate the accumulation
of parts of the matorial under treatment.
Besides the advantages already specified, this improved arrangement has the
further merit that it enables various kinds of material to be sifted or bolted
successively in the same apparatus; and the realisation of the various advantages
referred to is further ensured by the power or violence with which the material
which is being sifted is projected against the several compartiments of the sifting
area, whereby it is effectually prevented from becoming embedded in the meshes of
the gauze. The passage of the material through such meshes does, indeed, take
pluce very rapidly, so that upon the whole this improved sifting or bolting machine
is adapted to produce comparatively speaking a far higher useful effect and yield,
than any machine of the same class hitherto constructed. It has been found, in
the course of one of the numerous experiments to which the invention has been
subjected that in point of fact, this machine would sift in a given time not less than.
seven times the quantity of material that an ordinary cylindrical sifter or bolter is
capable of dealing with in the same period.
A modification which deserves notice in conclusion is represented in Figure 6 of
the drawings, at the creased portion or compartment e. It will be seen that the
bands or fillets b, which here serve to join together the several compartments of the
sifting surfaco, are somewhat curved or arched, so that they offer less resistance to
the motion of the drum or cylinder, than they would do if they were flat.
Dated the 5th day of March 1895.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., Agents.
An Improved Sifting or Bolting Machine.
1,.THEODOR COHN of No. 70 Cottbuser Damm, Berlin, in the German Empire,
Dye-stuff 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 :-
The subject of this invention is a sifting or bolting machine, the plane, oylindrical
or other sifting surface of which is at a number of points folded at predetermined
angles, so as to cause the goods being sifted or bolted, as it is conveyed to tho
sifting surface by any convenient means, to be projected from the compartment,
into which it is at first delivered, first, some distance in the upward direction, and
next, at a predetermined angle, towards the succeeding compartment or com-
partments; the sifting surface being kept constantly in oscillatory motion for the
purpose. The material to be sifted is thus thrown or shaken from one compartiment
to the other, and the direction is controlled by, or dependent on, the angle at which
the sifting surface is folded at a given point, the arrangement being such that the

page_text: material is enabled to move but a very small distance within each compartment of
the sitting or bolting area. Owing to this arrangement, not only the material of
which the sifting surface consists (preferably silk gauze) is effectively protected,
but the meshes of the sifter or bolter are prevented from being clogged up or
obstructed. In addition to this, as will be readily understood from what has been
stated above, the power required for producing the necessary shaking motion of the
sifting or bolting surface need not be nearly as great as that which sifting or bolting
machines demanded hitherto; it being, in fact, perfectly easy to operate the
improved bolting or sifting machine by hand.
The invention will be best understood by reference to the drawings filed with
my Provisional Specification, in which-
Figure 1 is a plan of a plane horizontal reciprocating sifter or bolter.
Figure 2 is a longitudinal section thereof on lino y y, Figure 1.
Figure 3 is a plan of a sifter or bolter, also plane, but constructed in the
shape of winding stairs and adapted to perform a rotary (instead of a reciprocating)
motion.
Figure 4 is an elevation of the same.
Figure 5 represents a sifting or bolting dram constructed after the method
usual in ball-mills, that is to say, with a sifting surface of mainly cylindrical
shape, and
Figure 6 is a cross section corresponding to Figure 5.
As already stated, the sifting surface in all the forms of sifters or bolters
constructed in accordance with this invention, is folded or creased at a certain
angle and at certain points of its area, with the result that the sifting surface is
divided into a number of compartments, from one of which the material to be sifted
starts on its way towards the discharge end of the machine, being shaken, as it
proceeds, from one compartment of the series to the next, until it reaches the
outlets in a properly sifted condition. Referring, for example, to the form of
Bifter shown in Figures 5 and 6, if it be assumed that the cylinder or druin revolves
in the direction of the arrow, it will readily be seen that the material which may
be supplied to the slowly rotating drum by any convenient feeding device, such as
a conveyor-screw, is first taken up, from the sifting surface a of the particular
compartment on which it first descends, to a distance equal to about half the
height or depth of such compartment; then down again, aud, as a natural conse-
quence of the rotary motion of the drum, and of its momentum, is dropped in a
practically vertical direction into the following compartments of the sifting surface,
situated on lower levels.
The connection between the several compartments of the sifting surface, which
are mounted in frames c of any convenient shape or construction, is effected by
means of fillets or bands 6 arranged at an angle to each other wherever two adjacent
sieve-compartments meet. This angle is not, as in some well-known sifting
machines, an acute angle, but an obtuso one, which, however, should but very
slightly exceed 90°. Owing to such an arrangement there are not formed anywhere
in the sifter any corners or recesses which would be calculated to facilitato the
accumulation of parts of the material under treatment.
Besides the advantages already specified, this improved arrangement has the
further morit that it enables various kinds of material to be sifted or bulted
successively in the same apparatus ; and the realisation of the various advantages
referred to is further ensured by the power or violence with which the material
which is being sifted is projected against the several compartments of the sifting
area, whereby it is effectually prevented from becoming embedded in the meshes
of the gauze. The passage of the material through such meshes does, indeed, take
place very rapidly, so that upon the whole this improved sifting or bolting machine
is adapted to produce comparatively speaking a far higher useful effect and yield,
than any machine of the same class hitherto constructed. It has been found, in
the course of one of the numerous experiments to which the invention has been
subjected that in point of fact, this machine would sift in a given time not less than

page_text: seven times the quantity of material that an ordinary cylindrical sifter or bolter is
capable of dealing with in the same period.
A modification which deserves notice in conclusion is represented in Figure 6
of the drawings, at the creased portion or compartment e. It will bo seen that the
bands or fillets b, which here serve to join together the several compartments of
the sifting surface, are somewhat curved or arched, so that they offer less
resistance to the motion of the drum or cylinder, than they would do if they
were flat.
Having now particularly described and ascertained the nature of my said,
invention, and in what manner the same is to be performed, I declare that
what I claim is-
A sifting machine wherein the sifting or bolting surface, which may be plane,
cylindrical, drum-shaped, or of any other suitable configuration, consists of a number
of divisions or compartments, such as a, which, by means of fillets or bands, sneh as b,
are so connected or joined that each compartment in conjunction with the next
following compartment forms inwardly an open obtuse angle, so that the material
to be sifted carried upwardly to a certain height or lovel on the first compartment
on which it falls, re-descends as the motion of such compartment is continued, and,
owing to the direction of motion of the remaining compartments situatod lower
down, and also owing to its own momentum, drops through the meshes of the
successive compartments along a perfectly vertical line.
Dated this with dox of March 1895
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicant.