An Improved Machine for Classifying or Sizing Materials.
Year: 1890

page_text: Date of Application, 12th Dec., 1890
Complete Specification Left, 14th Sept., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
An Improved Machine for Classifying or Sizing Materials.
I THOMAS CLARKSON Civil Engineer of Elm Tree Villa, Battersea in the
County of Surrey do hereby declare the nature of this invention to be as
follows:-
This invention relates to a certain improved construction of machine for
classifying or sizing materials and has for its object to provide a simple and
efficient machine which also can be easily taken to pieces and put together again,
so as to facilitate inspection and be conveniently portable.
According to my invention I arrange one above the other a number of frames
with perforated screens of varying meshes, the coarsest being in the top and the
finest in the bottom frame. The screens are mounted in a main frame preferably
on transverse rods passing through slots in its sides, and are capable of vibratory
motion which may either be steadily effected by small excentrics or equivalents
connected by detachable hooks to the screen frames and operated by a rotating
spindle; or it may be a percussive shake effected by springs alternately compressed
or extended and suddenly released by cam or other equivalent devices, also
operated by a rotating spindle driven by any convenient motor or power.
In order to facilitate the travel of the material upon the screens to the discharge
end and control the same, I may suspend the screens from links arranged in pairs
at each side, and adapted for adjustment of inclination by a radial slot in a carrying
plate fixed to the machine, the lower ends of each pair carrying the screen rods
which work through the said slots in the machine frame. Each screen is provided
at one end with a discharge orifice and these are preferably above one another at
one end of the machine and connected by shoots to separate receivers between
each pair of screens a removable catch apron is fitted. These join the frame at
the discharging ends of the screens but do not extend to the other frame of the
machine, a suitable opening being left, and that end of each apron next to the
opening is or may be perforated and slightly turned down to facilitate the descent
of material to the next screen below. Between each pair of screens is mounted
a rotary endless band or chain carrying brushes adapted both to sweep the lower
surfaces of the screens and the upper surfaces of the catch aprons. The bands
are driven by any suitable arrangement of pulleys and belts from the prime motor,
and the end spaces of the frame between the screens are filled in by airtight
boards. A feed hopper with adjustable slide is provided at the top of the machine
and in combination with the machine an exhaust fan is or may be provided acting
about the base below the lowest screen-this serves to facilitate the downward
tendency of the particles, but when it is used special provision must be made to exclude
air at the screen discharge orifices and other parts except the top. Air may be
excluded for all practical purposes from the discharge orifices by the use of a
hopper with a valve opening outwards against a spring. Rubber flaps are or may
be employed, to exclude air from the parts where the screen frames project through
the machine frame.
Provision is made for all parts being as simple as possible and connected together
so as to be readily attached and detached.
In operation the material that will not pass through any screen is discharged at
its end, while that which does pass through falls on to the next lower catch apron
and is travelled back along same by the brushes and passed down the apron
perforations or apertures to the next screen, and so on until the finest material

page_text: reaches the lowest screen; the operation being assisted by the downward draught
when a fan is used.
Dated this 12th day of December 1890.
J. C CHAPMAN,
Agent.
COMPLETE SPECIFICATION.
An Improved Machine for Classifying or Sizing Materials.
I THOMAS CLARKSON, Civil Engineer, formerly of Elm Tree Villa, Battersea
but now of Fairholme, Egmont Road, Sutton in the County of Surrey, do
hereby declare the nature of this invention and the manner in which the same is
to be performed to be particularly described and ascertained in and by the
following statement :-
This invention relates to a certain improved construction of machine for
classifying or sizing materials and has for its object to provide a simple and
efficient machine which can be readily disconnected and put together again for
facility of transport and inspection.
1 will describe my invention in reference to the annexed drawings in which like
letters refer to like parts.
Figures 1, 2 and 3 are respectively side and end elevations and a plan of the
machine.
Figure 4 is an enlarged sectional elevation of one pair of screens and details.
Figure 5 is a cross section on line 1-2 thereof.
Figures 6, 64, 7 and 8 are details.
Figures 9 and 10 are respectively a skeleton elevation and plan of a modified
arrangement hereinafter set forth.
According to my invention I arrange horizontally one above the other any
required number of frames for example A' A2 A3 A4 A5 A5 each carrying a
perforated screen. The screens are of varying mesh, the coarsest (for example 40)
being in the top and the finest (for exaniple 120) in the bottom frame. These
screen frames are carried horizontally on transverse rods a. a. which in some cases
may simply be supported in slots b. b. in the sides of the main frame and casing B
so as to be capable of vibratory motion. Instead of this arrangement and in order
to provide for adjustment of the rate of travel of the material along the screens
to the discharge orifices as hereinafter explained, the screens may be suspended
as illustrated from links L arranged in pairs at each side of the frame and adapted
for adjustment as aforesaid in segmental slots r in carrying plates R fixed to the
frame B; the lower ends of each pair of links L L are attached to the vibrating
screen-carrying rods a- extended through the clearance slots b in the frame;
and a thumbscrew and nut is provided to fix the position of the points of
suspension of the links in the slots ».
A modified method of suspending and adjusting the motion of the screens is
illustrated in Figures 9 and 10. Instead of segmental slots the suspending links L
are slung from side bars QQ sliding in guides gq fixed to frame B and connected
together by rod 2, and one of them is pivotted to a bell crank lever Q fulcrumed
on frame at ' and provided with a segmental guide and thumbscrew S as illustrated
in Figure 9 near the handle, by operating which the parts will take the position
shown dotted, and the angularity of the links L and thereby the direction of
motion of the screen can be regulated and fixed at will. To further explain, if
the links are fixed truly vertical the direction of motion of the screen will be a
practically true horizontal longitudinal reciprocation, but if the links are fixed
obliquely in the least degree the direction of motion becomes compound, being
partly longitudinal and partly vertical, hence a forward throw is imparted at each
vibration to the screen and the material upon it, and thus by adjusting the obliquity
of the links the rate of travel of the material upon the screen can be regulated

page_text: exactly as required. The vibratory motion may be a steady shake imparted by
small eccentrics c. c. mounted opposite each screen frame upon a vertical spindle S
mounted in bearings s. s and rotated through pulley P by any suitable power.
The eccentrics are connected by detachable hooks c' to rubber blocks or eyes.c³
mounted in blocks a' bolted to the frame ends as illustrated in Figures 1.4 and 6,
or the eccentric rod may pass through a hole in a strap c³ and be fitted with
equivalent springs and nuts as illustrated in Figure 64, and in either case a
noiseless and flexible connection is ensured; or the same motion may be produced
by triangular cams working between parallel faces, in a stirrup attached to cach
frame; ; or, a percussive shake may be effected by springs alternately compressed.
or extended and then suddenly liberated. by cams or equivalent devices similarly
mounted upon and rotated by the spindle S, as will be readily understood....
Discharge orifices D D Figures 4 are formed across the full breadth of one end
of the main frame opposite each screen end, and each one has an inclined shoot d...
Figures 2 and 4 leading to a separate vertical discharge channel, and these channels
are or may conveniently be grouped in casings D' D disposed at either side of the
machine, with diverging extremities and leading to separate receivers (not illustrated.
but being simply removable boxes).
In combination with the above described machine between each pair of screens
I provide a catch apron E Figures 4 and 5 which joins or approaches as shown to..
the frame at the discharge end but not at the back end, a suitable opening O, being
left thereat; and the adjacent end part of each apron E may be perforated as
illustrated in Figures 4 and 7,, and slightly turned down, as dotted if desired, to.
facilitate the descent of the materials to the next lower screen.
Above each catch apron is mounted a pair of endless bands or chains F rotating
in the direction of the arrows, and carrying brushes supported at each end and
directed by guides ƒ on the main frame and adapted to sweep and clear the lower
surface of every screen and the upper surface of each. catch apron, upon which
latter also the brush acts as a conveyor ;. the chains F are actuated by the chain
wheels mounted on axes projecting outside the inain frame and driven through
double pulleys and bands ff Figures 1 and 2 at-same-speed-and-in same direction
by the prime motor as shown at "; or other suitable equivalent driving medium
may be substituted.
The end spaces of the main frame between the screens are filled in by air tight
doors e. e.; H is the feed hopper with adjustable slide arranged at the top of the
frame above the uppermost screen A¹.
In combination with the machine above described an exhaust fan is or may be
provided acting through exhaust pipe X below the lowest screen A*.
This serves to facilitate the downward tendency of the particles and when it is
combined the rubber air excluding flaps el el are kept tight, and special provision
is made to exclude air at the screen discharge orifices and other parts, except the
top. This is effected by fitting in the orifices of the shoots d flap valves normally
held closed by a light spring but adapted to open outward by the weight of
accumulated materials as shown in Figure 8; or, the discharge orifices of the
shoots d may be made of just sufficient size to deliver the material and thus the
ingress of air is practically avoided.
In operation the material that will not pass through any screen is discharged at
its end while that which does pass through falls onto the next lower catch apron
and is travelled back along same by the brushes and passed down the apron
perforations or aperture to the next screen, and so on until the finest material
reaches the lowest screen, the operation being assisted by the downward. draught
when a fan is used.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A classifying and sizing machine consisting in the combination of a main
1°

page_text: enclosing frame carrying a series of superposed horizontal vibratory frames fitted
with screens of meshes varying from the coarsest in the top to the finest in the
lowest frame, each screen frame being carried on transverse rods supported and
working is slots in the sides of the main frame and caused to vibrate either with a
regular shake by eccentrics arranged as specified or by triangular cams; or, with
a percussive shake by cam and spring action, and driven by a vertical rotary shaft;
discharge orifices at one end of each screen each connected by a separate channel
to a separate receiver, all substantially as and for the purposes set forth.
2. In a classifying machine such as above described and claimed the combination
with a pair of horizontal vibratory screens of the intermediate catch apron E having
aperture and endless bands or chains FF carrying clearing brushes f. f. all
substantially as shown for the purpose specified.
3. In a classifying machine such as is above described and claimed instead of
supporting the transverse screen-frame rods a. a. in slots extending them through
clearance slots in the frame and suspending them from links L adjustable in
segmental slots with thumbscrews for adjusting and fixing the angularity of said
links and thereby the direction of motion of the screens, for the purpose of
regulating the rate of travel of the materials to the discharge orifices; and subject
to the modified suspending arrangement described in reference to Figures 9 and 10,
substantially as set forth."
4. A classifying and sizing machine constructed and arranged substantially as
hereinabove set forth and combined with the pipe X arranged below the lowest
screen and connected to any suitable exhauster, air excluding devices being provided
when required as and for the purposes described and illustrated.
Dated this 12th day of September 1891.
J. C. CHAPMAN,
Chartered Patent Agent, 70, Chancery Lane, London W.C.,
Agent for Applicant.