Improvements in or relating to Sifting Machines
Year: 1897

page_text: PROVIDIUNAL DIEVITICATION.
"Improvements in or relating to Sifting Machines."
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 certain improvements in sifters whereby they
shall be run much more smoothly and evenly, and the sieves shall be uniformly
and well cleaned.
In place of the ordinary flat trays I form the trays of a series of short inclined
planes curved over and dropping vertically or thereabouts at the upper end, and
approaching very near to the next incline or corrugation, but leaving a space large
enough to allow some of the material to pass through at each re-entering angle
formed by these corrugations or inclined planes. At any convenient point or
points more especially the centre I may have the tray perfectly flat instead of
being supplied with these corrugations. The feed is at the end of the sieves
toward which the inclined planes face and rubber balls or other like material
are fed on to the trays in order that by the motion of the machine these balls
may be sent flying up against the sieves and thus clean the same.
When they
get to the end of the sieve they enter a cross passage, the bottom of which inclines
in the reverse direction and this cross passage is brought round to the commence-
ment of the feeding end of the tray. In order to enable the circular motion of
the sifter to be extremely uniform and devoid of violent jerks I form the crank
shaft driving the sifter with a very long crank passing upwards through a pre-
ferably square tube in the centre of the sifter. In this square tube a bearing
is fixed formed in two halves and having a spherical bulge resting on a suitably
shaped spherical seat in the tube. The two ends of the bearing are held tight
by metal rings. Above and below the crank I place counterweights and beyond
them the bearings. The counterweights are generally far enough apart to enable
one to enter the bearing and withdraw the same between the upper counterweight
and the top of the plansifter, the two counterweights being preferably exactly
the same distance from the centre. The mode of action is as follows:-The
material being fed at one end the finer matter falls through on to the tray below.
The balls being introduced on the tray below by the shaking or rotary action of
the machine travel up each inclined plane successively and strike the underneath
side of the sieve falling down on to the next plane and this goes on until each
ball successively reaches the end of the tray which in some cases is provided with
small vertical pegs when it passes back again through the side channels.
material falling on to the tray passes through the slits at the bottom of the vertical
part of each corrugation and is shot forward on to the next sieve thus allowing
for the forward travel of the material on the sieve, consequently each sieve in
The

page_text: succession is fed nearly evenly over its surface from the sieve above notwith-
standing the forward motion of the particles. Any number of sieves and trays
may be superimposed.
100
. TA
100%
"
Improvements in or relating to Sifting Machines.”
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 manuer
the same is to be performed, to be particularly described and ascertained in and
by the following statement:
-
This invention has for its object certain improvements in sifters whereby they
may be run much more smoothly and evenly than heretofore, and the sieve shall
be uniformly and well cleaned.
The invention is best described by aid of the accompanying drawings showing
a sifter made in accordance with my invention, in which
Fig 1 is a horizontal section under the sieve,
Fig 2 a side elevation,
Fig. 3 a section through the line Y Y of Fig 1, and
Fig 4 a section through Z Z of Fig 1.
In these AA are the silks which are of the usual kind. Beneath these are the
trays B which are formed of a series of short inclined planes with their upper ends
curved over and dropping down vertically or thereabouts and approaching very
near to the lower part of the next incline, but leaving a space large enough to
allow some of the material to pass through at each re-entering angle formed by
these corrugations or inclined planes. At any convenient point or points pre-
ferably in the centre I form the trays with a flat surface C instead of having
corrugations. 1) is the feeding device entering one end of the upper sieve and
towards this end the inclined planes face. Rubber balls or other like cleaning
material such as large seeds or nuts are fed on to the trays in order that by the
motion of the machine these balls may be sent flying up against the sieve and
thus clean the same. I make no claim however for balls or cleaning devices
Per se as they are wellknown. When the balls get to the end of the sieve they
enter an opening E into a return passage F. In this return passage the trays
are solid and have their faces pointing in the reverse direction. These accord-
ingly send the balls flying back to the upper ends of these side passages where
they escape at other side passages G. In the drawings there are two sets of central
passages one on each side of the flat portion of the sieve. If desirable however
these passages can be at the sides of the sieve instead of in the centre and the
balls can be made to traverse the entire length of the sieve. Balls can be placed.
also in the central portion but I prefer the central portion to be made impervious
to material or simply used as a place in which the material which has already
been sent to somewhat one side of the sieve by the rotary motion is spread out
evenly over the surface of the sieve. For this purpose the opening through
which the material has to be passed is considerably curtailed. The material
consequently fills the entire opening and is thus evenly distributed over the sieve.
In order to enable the circular motion of the sifter to be extremely uniform and
devoid of violent jerking I form the crank shaft driving the sifter with a very
long shallow crank passing upward through the preferably square tube in the

page_text: centre of the sifter. In this square tube a bearing H is formed in two halves
having a spherical bulge restin on a suitably shaped spherical seat in the tube.
The two ends of the bearing are held tight by metal rings I I, the lower ring
being carried by the tube and the upper ring being held down by two or more
adjusting bolts from above. Above and below the crank I place two counter-
weights J and beyond them in any convenient position the bearings and driving
pulley. The counter-weights are generally far enough apart to enable the bear-
ing to be withdrawn when required from between the upper counter-weight and
the top of the sieve, the two counter-weights being preferably at exactly the
same distance from the centre. K is an annulus fixed to the top of the tube
carrying the adjusting bolt which presses the upper cap down and above this is
preferably a leather washer to keep it dust tight. L L are oil cups. The mode
of action is as follows;-The material being fed in at the upper end of the sieve
at D the finer matter falls through the sieve on to the tray below. The balls
being introduced on the tray below are caused to travel up each inclined plane
in succession by the shaking or rotary action of the machine and to strike the
underneath side of the tray which in some cases is provided with small vertical
pegs so as to increase the effect. The ball falling down on the next plane goes
up the succeeding one and so on until it reaches the end of the sieve when it
dances about until it strikes the exit E. The inclines now being pointed in the
opposite direction it flies back up these till it reaches the end of the central
passage, when the ball again enters the main sieve through the hole G the
materials falling through each tray in succession pass through the slits at the
bottom of the vertical part of each corrugation and in so doing are shot forward
on to the next sieve thus allowing for the forward travel of the material on the
sieve, consequently each sieve in succession is fed nearly evenly over its surface
provided the upper sieve be thus fed evenly notwithstanding the motion of the
particles on each sieve being downwards. Any number of sieves and trays can
be superimposed.
!
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. The combination with a sieve or series of sieves in a sifting machine of a
tray or trays formed with corrugations substantially as and for the purposes
described.
2. The combination with a corrugated tray of openings at the bottoms of each
corrugation substantially as and for the purposes described.
3. The corrugated return passages G substantially as described.
4. The combination in a sifting machine of a central crank balanced sub-
stantially as described and a globular bearing held between two rings and
arranged as near as possible in the centre of gravity of the sifter both vertically
and horizontally.
5. The combination of corrugated trays substantially as described with a
central or other flat portion and restricted passage whereby the material in the
trays which may have congregated more to one side is again evenly distributed
over the surface.
ated tha
day OT November
•
WM. P. THOMPSON/& Co.
Of 6 Lord Street, Liverpool, Patent Agents for the Applicant.
WM. P. THOMPSON/& Co.
Of 6 Lord Street, Liverpool, Patent Agents for the Applicant.