IMPROVEMENTS IN SCREENS FOR SIFTING COAL AND OTHER MATERIALS
Year: 1879

page_text: LETTERS PATENT to John Warrington, of Crag Wood, Rawdon, near Leeds, in
the County of York, for the Invention of "IMPROVEMENTS IN SCREENS FOR
SIFTING COAL AND OTHER MATERIALS."
PROVISIONAL SPECIFICATION left by the said John Warrington at the Office
of the Commissioners of Patents on the 4th July 1879.
JOHN WARRINGTON, of Crag Wood, Rawdon, near Leeds, in the County of York.
"IMPROVEMENTS IN SCREENS FOR SIFTING COAL AND OTHER MATERIALS."
The object of my Invention is to save time and labour, and to more perfectly
sift or screen coal or other materials.
Machines now in use have their bars placed in a longitudinal direction or in the
direction of the incline of the screen.
In my arrangement I provide elliptical rotating bars transversely and in suitable
bearings within the framework. These are caused to revolve in one direction by
ordinary gearing, motion being imparted thereto by hand or from some other
suitable motive power. The effect of this transverse arrangement of rotating bars
is to keep the coal constantly moving during the screening or sifting operation and
at any desired speed, such speed varying in accordance with the motion of the
elliptical bars.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Warrington in the Great Seal Patent Office on the 3rd
January 1880.
JOHN WARRINGTON, of Crag Wood, Rawdon, near Leeds, in the County of York.
"IMPROVEMENTS IN SCREENS FOR SIFTING COAL AND OTHER MATERIAL."
The object of my Invention is to save time and labour, and to more perfectly
sift or screen coal or other materials.

page_text: -bearings within the framework. These are caused to revolve in one direction by
ordinary gearing, motion being imparted-thereto by hand or from some other
suitable motive power. The effect of this-transverse arrangement of rotating bars
is to keep the coal constantly moving during the screening or sifting operation and
_at any desired speed, such speed varying in accordance with the motion of the
elliptical bars.
And in order that my Invention may be more completely understood, reference
is-given to-the-accompanying Drawings and to the letters and marks thereon.
DESCRIPTION OF DRAWINGS.
Fig. 1 is a plan looking at the top; Fig. 2, a longitudinal section through A, B,
Fig. 1; Fig. 3, a part side elevation of screen shewing driving apparatus.
a represents the sides and framework of the screen; b is a plate of metal onto
which the material is teamed; c, the elliptical rotating bars; d, the gearing through
which the rotary motion is imparted to the bars c; e is a shaft on which part of
the gearing is mounted; this is carried in the bearings on the brackets f and g;
h is the driving pulley through which motion is conveyed to the gearing from some
suitable motive power, and is keyed onto the shaft i carried in suitable bearings on
the bracket g; j represents a set of plain bars of ordinary construction used on
screens, and are employed to render the screening process more complete; k is a
plate over which the screened material passes, and is of ordinary construction.
It will be seen by the Drawings that the elliptical bars c (which may be of any
required number and distance apart) have the effect of not only moving forward
the material operated upon, but allows the small particles to fall into some receptacle
below. The peripheries of the bars c retain throughout their rotation the same
distance apart..
Other equivalent means may be employed for giving motion to the rotating
elliptical bars.
Having now described the nature of the said Invention, and described by the
aid of Drawings how the same may be carried into practice, I would have it under-
stood that I do not limit myself to the exact limits, details, or configuration of the
parts I have described and illustrated by the accompanying Drawings, but what I
do claim and desire to be secured to me by Letters Patent is,
First. The arrangement and application of elliptical rotating bars e placed trans-
versely in the framework of screens, and caused to rotate by means of gearing, as
shewn, or other equivalent means, substantially as and for purposes herein set
forth.
Second. The arrangement and combination of the various parts forming the screen
for sifting coal and other materials, substantially as herein set forth.
++
In witness whereof, I, the said John Warrington, have hereunto set my hand
and seal, this Thirty first day of December, in the year of our Lord One
thousand eight hundred and seventy nine.
TANT
ADDIYAMAN