An Improvement in Screens for Sifting Granular Substances.
Year: 1892

page_text: Date of Application, 21st Sept., 1892
Complete Specification Left, 16th June, 1893-Accepted, 22nd July, 1893
PROVISIONAL SPECIFICATION.
An Improvement in Screens for Sifting Granular Substances.
I, THOMAS HAYNES Junr. of Radcliffe on Trent, in the County of Notting-
ham, Maltster, do hereby declare the nature of this invention to be as follows:-
My invention relates to screens for sifting granular substances, of the kind
where the material to be screened is fed from a hopper and runs down a sloping
screen, the finer particles falling through between the wires or bars while the
larger particles descend to the lower end of the slope. In such screens the
material becomes accelerated as it descends, and consequently the lower part of
the screen is comparatively ineffective. According to my invention, I divide the
slope into several steps and immediately below each step I provide an adjustable
check board so that as the grains or granules descend from one section of the slope,
they strike against this board and have the velocity which they had acquired
so far reduced that they start at a moderate pace along the next section of the
slope.
The check boards, which may be placed at various angles, are made adjustable
in position by sliding or otherwise so as to regulate as desired the passages under
them.
Dated this 21st day of September 1892.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Screens for Sifting Granular Substances.
I, THOMAS HAYNES Junr., of Radcliffe on Trent in the County of Notting-
ham, Maltster, 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:-
My invention relates to screens for sifting granular substances, of the kind where
the material to be screened is fed from a hopper and runs down a sloping screen,
the finer particles falling through between the wires or bars, while the larger
particles descend to the lower end of the slope. In such screens the material
becomes accelerated as it descends, and consequently the lower part of the screen
is comparatively ineffective.
According to my invention, I divide the slope into several steps, and, immediately
below each step, provide an adjustable check board so that as the grains or
granules descend from one section of the slope, they strike against this board and
have the velocity which they had acquired so far reduced that they start at a
moderate pace along the next section of the slope.
Fig. 1 of the accompanying drawings is a vertical section of a screen according
to my invention made with one intermediate step and adjustable stop, of which
Fig. 2 shews a modification. About midway of the screen, between a set of upper
bars A and a set of lower bars B, I make a step or drop C in front of which I
provide a board D that can be turned to various angles as indicated by the dotted
lines. In order to prevent the granules which are reflected from D from being
thrown over the sides of the screen, I provide a covering board E, which may be
held at various positions on the sides by steady pins or otherwise, as indicated in
Fig. 1, or may be hinged to D and arranged to be set at various angles to D as
indicated in Fig. 2. Obviously, instead of one step or drop, there may be several
PQ71

page_text: in the course of the screen, each provided with a check board and a covering
board.
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:
Dividing a sloping screen for sifting granular substances into several steps, each
provided with a suitable check board and a covering board, substantially as and for
the purpose herein set forth.
Dated this 16th dow of T 1000
ABEL & IMRAY,
Agents for the Applicant.