IMPROVEMENTS IN SIFTING OR SEPARATING MACHINES FOR BOLTING FLOUR AND SEPARATING AND PURIFYING MIDDLINGS
Year: 1878

page_text: LETTERS PATENT to Robert Henry Fenwick, of Dublin, in the County of
Dublin, Ireland, Miller and Millwright, for the Invention of "IMPROVEMENTS IN
SIFTING OR SEPARATING MACHINES FOR BOLTING FLOUR AND SEPARATING
AND PURIFYING MIDDLINGS."
Sealed the 23rd July 1878, and dated the 23rd January 1878.
PROVISIONAL SPECIFICATION left by the said Robert Henry Fenwick at the
Office of the Commissioners of Patents on the 23rd January 1878.
ROBERT HENRY FENWICK, of Dublin, in the County of Dublin, Ireland, Miller
and Millwright. "IMPROVEMENTS IN SIFTING OR SEPARATING MACHINES FOR
BOLTING FLOUR AND SEPARATING AND PURIFYING MIDDLINGS."
My Invention relates to the construction and arrangement of sifting and sepa-
rating machines for bolting flour and separating and purifying middlings.
My improvements have reference to,―
(1.) The construction of the reel known as the bolting reel, and the method of
fixing the gudgeons in the shaft or axis of same.
(2.) The arrangement of conveyors in combination with a diaphragm divided in
sections, arranged in the manner and for the purpose herein-after described.
(3.) A method of imparting a longitudinal oscillating motion to the screen frame
for the purpose of agitating the material passing over said screen frame.
(4.) To the use of divisions or compartments arranged in the air chamber of sepa-
rating or purifying machines, so that the draught or intensity of the exhaust through
any given section or compartment may be varied, and a greater blast of air be thus
caused to pass up through any particular portion of the screen for the purpose of
removing foreign matters from the middlings.
I propose to use for bolting purposes a reel with two cylindrical or polygonal
Price 6d1

page_text: coverings or sieves of cloth, the first or inner cylindrical or polygonal covering being
stretched over rings supported by arms or rods radiating from the shaft or axis of
the reel, which radiating arms or rods project through said first or inner covering in
order to carry or support the rings on which the outer covering or cloth is stretched.
The inner covering or sieve is of a tapering form, being of smaller diameter at the
front or feed end of the machine than at the back or discharge end. The outer
covering or sieve is throughout its length parallel with the shaft or axis of the reel,
thus there is a greater space between the inner and outer coverings or sieves at the
feed end of the reel than at its rear end. The object of this arrangement is to effect
the bolting of the flour in a more perfect manner than by the constructions of reels
at present usually employed.
Flour as fed to the machine contains a considerable quantity of fine material,
which will at once pass freely through the inner covering, therefore a greater space
is necessary between the two coverings or sieves at the feed end, while the increased
fall or incline resulting from the tapering form of the inner covering or sieve is
important as aiding the better bolting of the material which remains within the
inner covering or sieve until it arrives at or near the rear end of the reel. Another
advantage in thus arranging the inner covering or sieve is that a greater incline is
afforded for facilitating the passage of the flour from end to end of the reel.
To secure the gudgeons to the ends of the shaft of the reel I make a mortice or
slot half way through the shaft, and close to the end thereof, into which I drop a
nut. I then attach a metal cap to the end of the shaft, having a pivot projecting
from its face; through this pivot, which acts as the journal, I pass a screw bolt,
the threaded end of which catches in the aforesaid nut, and by means of which the
said cap can be secured to the end of the shaft, thus obviating the splitting and
injury to the end of the shaft resulting from the usual method of inserting gudgeons
in reel shafts.
In lieu of the ordinary form of archimedian screw conveyor with a continuous
blade or thread, I use conveyors having each a spiral line of cast-iron flights or
blades, which flights or blades not only serve to propel the flour onwards as the
conveyor rotates, but also act as coolers in separating and tossing it as it is moved
from end to end of the machine. Of these conveyors I place two underneath each
bolting reel, one over the other, and between these two conveyors I arrange a hori-
zontal diaphragm divided into a number of sections by means of slides, which may
be drawn at any given point along the length of the machine. By this arrangement
the quality of the flour after it has been bolted from the reel may be readily ascer-
tained at any point underneath the reel by simply drawing any one of the slides in
said diaphragm, and should it be found that the flour at the slide thus drawn is
sufficiently fine and pure, the flour is allowed to drop into the trough or channel
underneath, in which the second conveyor operates, and by which the flour is
removed completely from the machine fit for sacking.
Should the flour be not found sufficiently fine and pure for the purpose for which
it is required after being bolted through one bolting reel, I allow it to be conveyed
by the top conveyor to a spout at the end of the machine, which communicates
directly with a second bolting reel; and in order to facilitate the passage from one
bolting reel to a second or a third, I prefer to arrange two or more bolting machines,
one over the other.
I mount the screen frame in suitably constructed framework in a horizontal
position, and I impart to such screen frame a longitudinal oscillating motion by
means of a transverse shaft mounted at one end of the machine or screen frame,
on which shaft is fixed a cam which gears with a plate affixed to the end cross beam
of the screen frame in such a manner as to impart to it the desired longitudinal
motion necessary for the separating or purifying the middlings passing over it.
Owing to the peculiar construction of this cam I may alter its throw so as to increase
or decrease the to-and-fro motion of said screen frame, and thereby increase or
decrease the agitation of the material made to pass over it.

page_text: I divide the space over the said screen frame known as the air chamber into
separate compartments, each communicating independently and directly with the
exhaust fan; and by suitable adjustable slides I am able to regulate the intensity
of the exhaust or blast of air passing up through any particular section of the
screen.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Henry Fenwick in the Great Seal Patent Office on the 23rd
July 1878.
ROBERT HENRY FENWICK, of Dublin, in the County of Dublin, Ireland, Miller
and Millwright. "IMPROVEMENTS IN SIFTING OR SEPARATING MACHINES FOR
BOLTING FLOUR AND SEPARATING AND PURIFYING MIDDLINGS."
My Invention relates to the construction and arrangement of sifting and sepa-
rating machines for bolting flour and separating and purifying middlings.
My improvements have reference to,―
(1.) The construction of the reel known as the bolting reel, and the method of
fixing the gudgeons in the shaft or axis of same.
(2.) The arrangement of conveyors in combination with a diaphragm divided into
sections, arranged in the manner and for the purpose herein-after described.
(3.) A method of imparting a longitudinal oscillating motion to the screen frame
for the purpose of agitating the material passing over said screen frame.
(4.) To the use of divisions or compartments arranged in the air chamber of sepa-
rating or purifying machines, so that the draught or intensity of the exhaust through
any given section or compartment may be varied, and a greater blast of air be thus
caused to pass up through any particular portion of the screen for the purpose of
removing foreign matters from the middlings.
propose to use for bolting purposes a reel with two cylindrical or polygonal
coverings or sieves of cloth, the first or inner cylindrical or polygonal covering being
stretched over rings supported by arms or rods radiating from the shaft or axis of
the reel, which radiating arms or rods project through said first or inner covering in
order to carry or support the rings on which the outer covering or cloth is stretched.
The inner covering or sieve is of a tapering form, being of smaller diameter at the
front or feed end of the machine than at the back or discharge end. The outer
covering or sieve is throughout its length parallel with the shaft or axis of the reel,
thus there is a greater space between the inner and outer coverings or sieves at the
feed end of the reel than at its rear end. The object of this arrangement is to
effect the bolting of the flour in a more perfect manner than by the reels at present
usually employed.
Flour as fed to the machine contains a considerable quantity of fine material,
which will at once pass freely through the inner covering, therefore a greater space
is necessary between the two coverings or sieves at the feed end, while the increased

page_text: fall or incline resulting from the tapering form of the inner covering or sieve is
important as aiding the better bolting of the material which remains within the
inner covering or sieve until it arrives at or near the rear end of the reel. Another
advantage in thus arranging the inner covering or sieve is that a greater incline is
afforded for facilitating the passage of the flour from end to end of the reel.
To secure the gudgeons to the ends of the shaft of the reel I make a mortice or
slot half way through the shaft, and close to the end thereof, in which I drop a
nut. I then attach a metal cap to the end of the shaft, having a pivot projecting
from its face; through this pivot, which acts as the journal, I pass a screw bolt,
the threaded end of which catches in the aforesaid nut, and by means of which the
said cap can be secured to the end of the shaft, thus obviating the splitting and
injury to the end of the shaft resulting from the usual method of inserting gudgeons
in reel shafts.
In lieu of the ordinary form of archimedian screw conveyor with a continuous
blade or thread, I use conveyors having each a spiral line of cast-iron flights or
blades, which flights or blades not only serve to propel the flour onwards as the
conveyor rotates, but also act as coolers in separating and tossing it as it is moved
from end to end of the machine. Of these conveyors I place two underneath each
bolting reel, one over the other, and between these two conveyors I arrange a hori-
zontal diaphragm divided into a number of sections by means of slides, which slides
may be drawn at any given point along the length of the machine. By this arrange-
ment the quality of the flour after it has been bolted from the reel may be readily
ascertained at any point underneath the reel by simply drawing any one of the slides
in the said diaphragm, and should it be found that the flour at the slide thus drawn
is sufficiently fine and pure, the flour is allowed to drop into the trough or channel
underneath, in which the second conveyor operates, and by which the flour is
removed completely from the machine fit for sacking.
Should the flour be not found sufficiently fine and pure for the purpose for which
it is required after being bolted through one bolting reel, I allow it to be conveyed
by the top conveyor to a spout at the end of the machine, which communicates
directly with a second bolting reel; and in order to facilitate the passage from one
bolting reel to a second or third, I prefer to arrange two or more bolting machines
one over the other.
I mount the screen frame in suitably constructed framework in a horizontal
position, and I impart to such screen frame a longitudinal oscillating motion by
means of a transverse shaft mounted at one end of the machine or screen frame, on
which shaft is fixed a cam which gears with the end cross beam of the screen frame
in such a manner as to impart to it the desired longitudinal motion necessary for
the separating or purifying the middlings passing over it. Owing to the peculiar
construction of this cam I may alter its throw so as to increase or decrease the to-
and-fro motion of said screen frame, and thereby increase or decrease the agitation
of the material made to pass over it.
I divide the space over the said screen frame known as the air chamber into
separate compartments, each communicating independently and directly with the
exhaust fan; and by suitable adjustable slides I am able to regulate the intensity
of the exhaust or blast of air passing up through any particular section of the
screen.
In order that my said Invention may be more readily understood and carried
into practice I will proceed to describe the accompanying Sheet of Drawings.
Fig. 1 is a longitudinal section showing the bolting reels and a purifyer arranged
and constructed in the manner above described; Fig. 2 is a transverse vertical
section on line x, x, Fig. 1.
Figs. 3, 4, 5, and 6 are details herein-after described.
Similar letters indicate corresponding parts in all the views.
A, A, represents the framework of the machine; B, B, the axis of the bolting
reels; b, the framework of the inner cylinder or polygon; and c, the outer cylinder
or polygon of the bolting reel, on both of which the canvas or cloth is secured;

page_text: C, C, represents the conveyors with flights or blades arranged spirally around same,
instead of the usually continuous blade or thread after the maner of the archimedian
screw; D, D, shows the horizontal diaphragm lying between these conveyors, and
divided into sections, as herein-before described, for the purpose of allowing the
flour to fall from one conveyor to the other when required; F, F, represents the
screen frame for separating or purifying the middlings bolted from the reels over-
head, and which is suspended to the framework of the machine by the knuckle joints
ff, so that the said screen frame may swing freely to and fro in a longitudinal
direction. I arrange the upper joint of these knuckle joints in a longitudinal slot,
as shown by the dotted lines at f¹, f¹, and by moving the thumbscrews backwards
or forwards I am enabled to throw the screen frame out of centre, and thereby
increase the speed of the middlings passing over the surface of the screen.
Underneath the screen frame are two endless chains g, g, travelling on pulleys i, i,
which carry a transverse brush from end to end of the machine, the fibres of which
press against the under surface of the screen, and keep the meshes of same open
and clean. The pressure of this brush on the screen may be adjusted by the side
screws e, e, which act on supports p, p, which latter carry longitudinal guides r, r,
in which the endless chains travel.
H shows the chamber into which the middlings fall after having passed through
the screen, and from which they may be removed by the top conveyor, arranged and
operating underneath. If however the middlings are not sufficiently purifyed, they
are allowed to drop through the diaphragm D into the second conveyor, and from
thence are conveyed back to the bolting reel or to the purifyer, as the case
may be.
L, L, are separate compartments into which the air chamber is divided, each
communicating independently and directly through the channels t, t, with the exhaust
fan. The adjustable slides by which one or more of these compartments may be
rendered inoperative, or by which the intensity of the exhaust or blast of air passing
up through any particular section of the screen may be regulated, are seen at 1, 2,
and 3.
The arrows indicate the current of air passing up through the screen and the air
chamber, and on towards the fan.
S is a transverse shaft rotating in suitable bearings affixed to the framework of
the machine, on which is mounted the cam J, which operates in the frame y, the
latter being secured to the end cross bar of the screen frame. By the rotation of
this cam within the frame y it will be evident that an oscillating motion will be
imparted to the screen frame; this motion may be increased or diminished by altering
the throw of the cam, and thereby the agitation of the material passing over the
screen may be augmented or decreased.
K is the hopper; ¹, the feed roller; and k², a slide by which the supply of flour
to the purifyer may be regulated. This feed roller may be dispensed with if found
desirable, and any other method of adjusting the supply adopted.
W is a vertical shaft, which by means of bevil gearing imparts motion to the
bolting reels and conveyors.
Z is a pulley which carries an endless band, and by which means motion is
imparted to the screen frame or purifyer.
Fig. 3 is a detailed view showing the method of securing the gudgeons to the
axis or shaft of the bolting reels and conveyors. 4 is a nut dropped into a lateral
slot near the end of the axis; 5 is a metal cap, with bolt 6 passing through same;
the threaded end of this bolt catches in the aforesaid nut, and thereby secures the
metal cap tightly to the end of the axis or shaft, and prevents splitting or injury to
same, which frequently occurs, according to the usual methods of inserting gudgeons
in reel shafts.
Fig. 4 is a plan of the metal cap.
Figs. 5 and 6 are elevation and plan of the flights or blades, which are used
spirally around the conveyors, as herein-before described. Each flight is secured
to the shaft by means of screws which nass through the annular anace
Reen at 8

page_text: Fig. 6. By this annular space also the pitch of each flight may be readily
adjusted.
Having thus described the nature of my said Invention, and the manner of
working the same, I would have it understood that what I consider new and useful
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. The combination in sifting or separating machines for bolting. flour and
separating and purifying middlings, constructed, arranged, and operating substan-
tially as herein described in reference to Figs. 1 to 6 inclusive of accompanying
Sheet of Drawings.
Second. The employment of double bolting reels, constructed and operating in the
manner substantially as herein-before described and set forth.
Third. The use of double conveyors in combination with a diaphragm divided into
sections, all constructed and operating substantially in the manner and for the
purpose herein described.
Fourth. The method of securing the gudgeons to the axis or shafts of the bolting
reels and conveyors, substantially as herein described in reference to Figs. 3 and 4 of
accompanying Sheet of Drawings.
In witness whereof, I, the said Robert Henry Fenwick, have hereunto, this my
Specification, set my hand and seal, this Twentieth day of July, in the year
of our Lord One thousand eight hundred and seventy-eight.
Witness,
J. A. FAHIE, C.E.,
Patent Agent,
2, Nassau Street,
Dublin.
ROBERT HENRY FENWICK. (L.S.)