Improvements in Rotary Scalping Machines.
Year: 1893

page_text: Date of Application, 10th Apr., 1893—Accepted, 24th June, 1893
COMPLETE SPECIFICATION.
Improvements in Rotary Scalping Machines.
A communication from WILLIAM HEWITT MELDRUM, Miller, and HENRY
RICHARD SHAW, Millwright, both of the Town of Peterborough, in the County
of Peterborough, in the Province of Ontario, Canada.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Member of the Institution of Mechanical Engineers 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:-
The object of the invention is to construct a scalper which will occupy a small
space and perform its work without scouring the stock, and it consists essentially,
of a series of conically-shaped screens arranged alternately with a series of
conically-shaped conveyors connected together and caused to revolve at a moderate
speed within a circular casing carrying fixed ledges immediately below the outer edge
of each conically-shaped screen and conically-shaped conveyor to receive the brake
or middlings discharged therefrom, which brake or middlings is swept out of their
respective ledges towards a discharge spout by a series of scoops attached to the
revolving sieve or conveyor; substantially as hereinafter more particularly
explained.
Figure 1 is a sectional perspective view of the improved scalper.
The old style of scalper which consists of a revolving reel, scoured the stock to
such an extent that, comparatively speaking, but a small quantity of high grade
flour was secured. The scalpers made with horizontal vibrating screens are very
apt to get out of order and require constant attention and repair and both styles
occupy considerable room. By the adoption of the improved rotary scalper my
correspondents not only secure a scalper in which scouring of the stock is, practically
speaking, completely avoided, but which will occupy but very little space in
proportion to the work it will perform. In the drawing a machine is shown with
only two sets of screens, but it will of course be understood that the number of
screens may be increased to suit any sized mill.
A, represents the casing which is cylindrical in form and made a suitable size to
contain as many screens B as required, only two being shown in the drawing.
Below each screen is placed a conveyor C. The conveyors are made of smooth
wood or any suitable close material, and like the screens the conveyors are conical
in shape so that the stock will elide towards their edge and fall onto the ledge D,
located immediately below the edge of each screen and conveyor.
The screens B, and the conveyors C are rigidly secured together by the bolts or
rods E, as indicated in the drawing. Around the inner edge of each conveyor Ca
partition is formed to prevent the brake or middlings falling off the said ledge.
From the edge of each screen B and conveyors C, a series of independent
scoops F, project so that when the machine revolves, they will push the brake or
middlings off the respective ledges into the spout G or H. The screens B and
revolving conveyors C are as before stated, rigidly connected together and are
provided with a central shaft I, which rests in a suitable step J. This shaft
is properly geared, as indicated, to a horizontal shaft K, or it may be geared by
any other suitable means to a power from which it is driven.
Having now referred to the principal mechanical parts involved in the invention,
I shall proceed to describe briefly the operation of the machine.
The stock is conveyed onto the top screen through the hole L, made in the top of
the machine. The stock thus conveyed is sifted so that the middlings will fall
gently through the mesh of the screens onto the conveyor C, immediately below the
top screen. The brake slides down towards the edge of the top screen and falls

page_text: onto the top ledge D, immediately below it while the middlings slide towards the
outer edge of the conveyor and fall onto the ledge D, immediately below it. All
this time the screens and conveyors are slowly revolving, say, at the rate of about
thirty revolutions a minute and the scoops Fact upon the brake so as to push it
towards the spout G and the scoops F which act on the middlings push it towards
the spout H, which convey them to their respective points where they are put
through the next process. As it is found, a slight jarring or vibratory motion for
the revolving screens makes the revolving screens operate with greater satisfaction,
one or more agitators are provided for producing the desired result. This agitator
may be variously constructed, a practical form being shown in the drawing which
consists of the roller L of an irregular form such as a hexagon journalled on the end
of a pivotted arm M and actuated by a spring which holds the roller against the
surface of the screen so that as the screen moves, the roller is caused to revolve,
and owing to its irregular form, agitates the screen as desired.
In order to convey the stock onto the lower screens, a hole is made in the centre
of the screens through which a central feed spout O is carried. As there are only
two screens in the machine illustrated, only one feed spout O will be necessary, but
as each additional screen is added a separate feed spout O is provided.
As well as providing agitators for the screens they may also be provided for the
revolving conveyors.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents and in what manner the
same is to be performed I declare that what I claim is ;-
1. A conically-shaped revolving screen arranged within a casing and designed to
receive the stock substantially as and for the purpose specified.
2. A conically-shaped revolving screen arranged within a casing and designed to
receive the stock in combination with a flanged ledge located below the outer edge
of the screen and of a series of scoops connected to the outer edge of the said
revolving screen substantially as and for the purpose specified.
3. A conically revolving screen arranged within a casing and designed to receive
the stock a conically-shaped revolving conveyor located below the conically-shaped
revolving screen in combination with ledges located below the outer edges of the
screen and conveyor and of scoops connected to the said screen and conveyor
substantially as and for the purpose specified.
4. A conically-shaped revolving screen arranged within a casing and designed to
receive the stock in combination with means for imparting a vibratory motion to
the said revolving screen substantially as and for the purpose specified.
Dated this 10th day of April 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicant.