Improvements in Apparatus for Sifting or Screening Flour and other Materials,
Year: 1888

page_text: Date of Application, 5th June, 1888
Complete Specification Left, "20th Feb., 1889
Complete Specification Accepted, 30th Mar., 1889
Improvements in Apparatus for Sifting or Screening Flour and
other Materials,
I, HEINRICH SECK of Dresden in the Kingdom of Saxony and German Empire do
hereby declare the nature of this invention to be as follows .-
-
This invention relates to sifting or screening apparatus for sifting flour and the
like and comprises the combination, with a sieve particularly intended for sifting
flour and the like of swinging or hinged doors or flaps preferably trap doors swinging
on a horizontal axis for the purpose of controlling the motion of the material being
sifted which latter may either be a rocking reciprocating, or a rotary sieve
In carrying the said invention into practice I construct the sieve with a series of
vertical flaps or hinged doors pivoted at the top and which may swing from their
vertical position to the left but not to the right
The material to be sifted is fed into
the sieve between the vertical hinged doors or flaps. Now, if the sieve is pushed or
moved to the right, the vertical doors will be flung open and a part of the flour shot
forward underneath the said doors Supposing now the direction of the motion of
the sieve to be reversed, the doors or flaps will be caused to fall into their vertical
position and be closed by the weight of the material wluch has been previously shot
through the open doors and which cannot now return to the same point behind the
door where it originally was, but must remain in front of the closed door. By this
means a steady and regular motion of the material on the sieve is ensured in the
direction in which the trap doors open.
The advantages that are attained by this method of combining with the sieve, the
said trap-doors, are as follows the surface of the sieve may be made horizontal,
while heretofore it had to be made inclined, that is higher at the end where the
material entered, in the case of reciprocating or rocking sieves. The movement of
the material was, therefore, dependent on the position of the sifting surface. The
same is also true with regard to rotary sieves where there are no means employed
for moving the material onward. But in rotary sieves having such means the
movement of the material depends on the direction in which the sieve is moved

page_text: or rotated, that is to say, such sieves are rendered inoperative and are apt to be
damaged or do damage in case they should happen to be rotated in a direction
The sieve constructed according to
opposite to that for which they are constructed
the present invention can be rotated in either direction or may be rocked and will
always produce the same results.
In practice the doors or flaps would not extend over the entire width of the sieve
but would be so arranged that the whole sieve is divided by partitions or longitudinal
walls so as to form as it were four sieves placed side by side; the material passing
from the first into the second then into the third and so on always moving in
opposite directions, the doors opening in opposite direction in each adjacent part of
the whole sieve the several parts of the sieve being connected by similar doors or
flaps. The doors may if desired he made reversible by so arranging the said doors
to swing out in either direction and arresting their motion, by a pin arranged below
and at one side of the pivot of the door or by any other suitable device. If this pin
is taken out and placed so as to engage with the opposite side of the doors, the
material will run over the sieve in an opposite direction to that above described.
The motion of the sieve no matter whether it be rocking or rotating from the right
to the left or from the left to the right, remaining unchanged. With this apparatus
the sitting operation takes place more regularly than heretofore each trap when closed
throwing the material through the door just in front at the time of the return motion
of the sieve the opened doors will then close again and prevent parts of the material
thrown through the doors, from returning behind the said door. The material will
thus be moved quickly to and fro between the several doors and advance with great
regularity so that the best possible results are attained
Dated this Fifth day of June 1888.
HASELTINE, LAKE & Co.,
45, Southampton Buildings,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION
Improvements in Apparatus for Sifting or Screening Flour and
other Materials.
I, HEINRICH SECK, of Dresden, in the Empire of Germany do hereby declare the
nature of the said invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement.-
In the sifting apparatus heretofore employed the passage of the material to be
sifted is dependent on the position of the sieve which for example in shaking sifters
has to be inclined towards the discharge end, or in oscillating or rotary sifters either
on the inclined position, or, if special means for conveying the material to be sifted
are combined with the sieve on the direction of rotation or movement.
The present invention consisting in the novel combination of a sieve with a system
of flaps or door enables the sifting operation to be carried out without regard either
to the position of the sieve (which may be vertical or rising or descending towards
the discharge end) or to the direction of movement of the sieve, which may be a
rectilinear reciprocating movement or a rotary movement from right to left or
vice versa.
It is immaterial what position the sieve has or how the latter is moved,
the effect will always be the same, and no injury can be caused should the sieve be
turned in the wrong direction by the incautious use of a crossed belt.
In the accompanying drawing :-
:-
Figure 1 represents a vertical section on the line y-y, Figure 2, and
Figure 2 is a horizontal section on the line xx, Figure 1.
Above the sifting surface or seve e on the transverse slats c are secured the flaps
or doors d which can swing freely from their normal vertical position to one side
The drawing represents a rotary sifter in which two sieves are arranged one above
the other, each sieve is enclosed by walls b b¹ and between the walls swing the doors
or flaps d. Each sifting surface may consist of a number of single sieves (in the
apparatus shown in the drawing there are six) the surface e of which may be
continuous.
In the arrangement shown the entire sieve or sieve box is suspended by means
of the supporting arms a³ and the rods a which are provided with nuts a¹ screwed
thereon and which have play in the supporting arms a² and in the upper part of the
frame A, in order to permit a rotary movement of the sieve box in every direction
This movement is caused by means of the crank shaft A2 provided with the driving
pulley A' and applied to the supporting arm A³ fixed to the sieve box.
In the motion of the sifter which in the apparatus shown is rotary, but which as
stated, may be rectilinear reciprocating motion, the doors open and close, that is to
say they are closed when the sieve is moved in the direction in which the doors open,
The latter movement may for the
and they are opened in the reverse movement
sake of brevity be termed "backward movement" and the reverse movement "forward
movement."
In the backward movement for example, the doors or flaps d fly open, and they
close in the forward movement The material, which is to be sifted and lies behind
the door passes when the said door opens through the same, by reason of its inertia

page_text: but it cannot in the reverse motion pass back through the door which is being closed,
it now bears against the same from the other side, in order to be thrown in the
succeeding backward movement through the next and so on
In the drawing where several compartments of the sieve are arranged side by side
the doors d always open and close in two contiguous compartments in reverse
succession as shown in Figure 2 where, in the forward movement that has taken
place 1, 3 and 5 are opened and 2, 4 and 6 are closed.
The contiguous compartments 1, 2, 3 and so forth are connected with each other
at the ends by similar doors or flaps d which in case the movement of the sieve is
rectilinear are preferably arranged on the incline as indicated on the right hand side
of Figure 2.
Figure 1 shows how the material to bo sifted in the movement of the sieve which
for one compartment of the apparatus is a "forward movement and for another a
"backward" movement, is thrown through the open doors d and also how it takes its
place before the closed doors through which it cannot pass back to its place.
Figure 2 shows in one of the compartments the movement of the material to be
sifted which receives a positive transport in the direction of the arrows by the opening
and closing doors it being as above stated immaterial in which direction the sieve is
moved or what position it occupies
If the doors d are arranged between the walls b¹ in such a manner that they can be
reversed, by adapting them to be swung to both sides and placing on one side a bolt
or pin which prevents its motion, the, material to be sifted after the displacement of
the bolt and the consequent reverse swinging of the doors can be caused to pass the
reverse way over the sifting surface that is to say in Figure 2 from 6 to 1, without
changing the movement of the sieve itself
The flour or other material is in this manner progressively sifted in the energetic
forward and backward movement, the danger of the closing up of the sifting surface
1s decreased and uniform sifting 1 ensured.
I wish it understood that without deviating from the nature of my present invention
the said flaps or doors may if desired be journalled in the stationary frame of the
machine and be flung open and closed by the material on the sieve below them with
the same result as heretofore described.
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
clann is
First The combination, with a sieve arranged in any plano and to be moved in any
direction, of flaps or doors which open during one part of the movement of the sieve
to allow the passage of the flour or other material and close during the other part of
the movement of the sieve in order to stop the material which has previously passed
through, for the purpose of causing an energetic forward and backward movement and
a positive progressive movement of the material.
Second. The combination with the sieve e of the flaps or doors d, substantially as,
and for the purpose set forth
Third The combination with a sieve e arranged in one compartment and provided
with flaps or doors d which are free to open in one direction, of a sieve e arranged in
another compartment and provided with flaps or doors which are free to open in the
reverse direction, substantially as, and for the purpose, set forth.
Dated this 20th day of February 1889
HASELTINE, LAKE & Co,
45, Southampton Buildings, London W C.,
Agents for the Applicant