Improvements in Separating Screens.
Year: 1891

page_text: Date of Application, 17th July, 1891
Complete Specification Left, 13th Apr., 1892-Accepted, 16th July, 1892
PROVISIONAL SPECIFICATION.
[Communicated from abroad by HEINRICH SCHÜCHTERMANN and Carl Josef
KREMER, of Dortmund, in the German Empire, Engineers.]
Improvements in Separating Screens.
I, HENRY HARINGTON LEIGH, Assoc. M. Inst. C.E., Fel. Inst. P.A., practising
as Phillips & Leigh at No. 22, Southampton Buildings, Chancery Lane, in the
County of Middlesex, Engineer and Patent Agent, do hereby declare the nature of
this invention to be as follows:-
This invention relates to improvements in separating screens and the object of it
is to provide for the screen receiving a vertical, a circular, or an elliptical motion
in place of the ordinary reciprocating linear one, although the latter can be
retained.
The driving or first motion shaft is fitted with eccentrics or cranks which connect
with the screen. A crank is fitted to the end of the said shaft and this is connected
by a suitable rod to a lever at the opposite end of the screen, which lever has its
fulcrum conveniently upon a transverse shaft. Further levers have their fulcra
upon the said shaft and these are connected to the opposite end or head of the screen
by connecting rods.
The position of the first mentioned crank with relation to the eccentrics on the
same shaft is such that when the screen is at middle height the said crank makes a
right angle with the first mentioned connecting rod which is also then at middle
height.
In this way and according to the length of the said crank and of the levers at the
lower end of the screen a vertical, circular, or elliptical motion is secured.
This vertical, circular, or elliptical movement of the screen prevents the screen
holes from being choked up with wet material, and allows the working of the
screen being regulated according to the quality of the material.
The same result can be obtained by suitably altering the cranks on the first
motion shaft.
Dated this 17th day of July 1891.
COMPLETE SPECIFICATION.
Improvements in Separating Screens.
I, HENRY HARINGTON LEIGH, Assoc. M. Inst. C.E., Fel. Inst. P.A., practising
as Phillips & Leigh, at No. 22, Southampton Buildings, Chancery Lane, in the
County of Middlesex, Engineer and Patent Agent, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particu-
larly described and ascertained in and by the following statement :—
This invention relates to improvements in separating screens, and the object of it
is to provide for the screen receiving a compound vertical-circular-elliptical
motion, the preponderance of either type of motion on the part of any particular
portion of the screen being according to the relative influence of the respective
members of the operating mechanism.
The driving or first motion shaft is fitted with eccentrics or cranks which connect
with the screen.
A crank is fitted to the end of the said shaft and is connected
by a suitable rod to a lever at the opposite end of the screen, which lever has its
fulcrum conveniently upon a transverse shaft. Further levers have their fulera
upon the said shaft and are connected to the end of the screen by links.

page_text: The above mentioned compound motion of the screen prevents the screen-holes
from being choked up with wet material, and allows the working of the screen being
regulated according to the quality of the material.
In order that this invention and the best means of carrying it into practical effect
may be thoroughly understood, I will now describe it and them in detail, referring
in so doing to the accompanying figures which are to be taken as part of this
Specification and read therewith.
Fig. 1 is a side elevation.
Fig. 2 is a longitudinal section along the line 2-2 of Fig. 3.
Fig. 3 is a plan.
Fig. 4 is a transverse section along the line 4-4 of Fig. 1, omitting the con-
necting rod.
Fig. 5 is an end elevation of the head of the screen.
a is the screen. bis the first motion shaft; and ', its driving pulley. c, care a
pair of eccentrics the sheaves of which are fast on the shaft and the straps fast to
the screen.
d is a half crank fast on the end of the shaft h. e is a rock-shaft
supported in any convenient way above the foot of the screen. is a vibrating arm
fast upon the said shaft and opposite to the half crank d. 9 is a connecting rod by
which the motion of the half-crank d is transmitted to the arm f. h, h¹ are a pair
of vibrating arms fast upon the shaft e at points respectively above the sides of the
screen and at an angle with the arm 1. i, are a pair of links respectively con-
necting the arms h, h² to the screen.
The position of the half crank d with reference to the eccentrics c is such that
when the screen is at middle height, the former makes a right angle with the con-
necting rod g which is also at middle height. The said half-crank and the arms f, h
and may be of variable length, and it is the combination of the above mentioned
position with the lengths of the said half crank and arms that decides the path of
any point in the screen.
i, are a pair of counter-balanced wheels on the shaft b. Their function is to
counteract the centrifugal momentum of the screen.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what 1
claim is :-
The combination of screen, eccentrics and a half-crank or their equivalents at the
head thereof, and a rock shaft and arms and links at the foot, as and for the purpose
set forth.
· Dated the 12th day of Anril 1809
HENRY H. LEIGH.