Improvements in Mills for Crushing and Grinding.
Year: 1893

page_text: Date of Application, 19th Apr., 1893
Complete Specification Left, 19th Jan., 14-Accepted, 19th June, 1894
PROVISIONAL SPECIFICATION.
Improvements in Mills for Crushing and Grinding.
We, WILLIAM DUFFIELD, of 7, Nelson Road, Chatham, Engineer, and
WILLIAM ROWLAND TAYLOR, of 2, Star Hill Villas, Rochester, Engineer, both
in the County of Kent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in mills for crushing and grinding
Portland cement, clinker or any other substance wet or dry by means of a revolving
or fixed pan with two or more heavy runners revolving on axles at and in suitable
speeds and positions, whereby a combined increased grinding and crushing surface is
obtained with considerably less power than by any other known mill for the same
purpose.
To carry out this invention, a bed plate or pan is fixed to a vertical shaft running
in a toe step at the bottom and a bearing at the top, and power is imparted to it
through any suitable gearing. This vertical shaft is fitted with cams or eccentrics
which revolve in a centre casting or mace which is fitted with two or more
receptacles for receiving cranks or arms which carry the runners or crushers. The
cranks or arms are made with spherical ends which are fitted to suitable receptacles
formed in the centre casting. The outer ends of these cranks or arms are carried
by globular bearings working in brackets which are at liberty to rise and fall or
turn to any angle or into any position to suit the throws of the cams or eccentrics
and are fitted with springs or buffers for adjusting the pressure of the runners on
the bedplate. The motion is imparted to the runners or crushers by the revolving
pan or bedplate coming in contact with it, and at the same time the vertical shaft
imparts motion to the cams or eccentrics which cause the centre casting to work in
The runners or crushers
and out according to the amount of throw of the cams.
revolve on the crank or arms and are kept in position by collars or other means,
and as they are fixed to the centre casting, they work in and out at the same time,
thereby causing a continuous scrupping or grinding in addition to the crushing
motion of the runners.
The runners are made of hard chilled iron, or any other suitable material with
flat or concaved faces, and revolve on a renewable path made of cast steel or any
other suitable hard material with a flat or convex surface to correspond. The
latter is or may be made in segments fixed to the pan or bedplate.
The mill can be fed at any part and the materials. to be ground distributed by
means of adjustable scrapers fixed to the centre casting, by which means the
materials are kept in constant agitation.
The materials when ground will pass off the bedplate by centrifugal force and
pass under an adjustable ring or other suitable arrangements placed near the
periphery of the bed plate which is fitted with various scrapers for passing back to
the runners or crushers the materials not sufficiently ground. The ground material
after passing under the ring passes over the edge of the bed plate and falls into a
receptacle from which it is collected by means of scrapers fixed to the under part
of the outer edge of the bedplate and scraped into the elevator pan or screw
conveyor.
Dated this 19th day of April 1893.
PHILLIPS & LEIGH,
Agents for the Applicants.

page_text: Improvements in Mills for Crushing and Grinding.
We, WILLIAM DUFFIELD of No. 7 Nelson Road, Chatham, Engineer, and
WILLIAM ROWLAND TAYLOR of No. 2 Star Hill Villas, Rochester, Engineer,
both in the County of Kent, 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:-
This invention relates to improvements in mills for crushing and grinding
Portland cement, clinker, or any other substance, wet or dry, by means of a
revolving or fixed pan with two or more heavy runners revolving on axles, at and
in suitable speeds and positions, whereby a combined increased grinding and
crushing surface is obtained with considerably less power than by any other known
mill for the same purpose.
In one form of mill made according to this invention, a plate or pan is fixed
to a vertical shaft running in a toe step at the bottom and a bearing at the top, and
power is imparted to it through any suitable gearing. This vertical shaft is fitted
with cams or eccentrics which revolve in a centre casting or mace. The latter is
fitted with two or more receptacles for receiving cranks or arms which carry the
runners or crushers. The cranks or arms are made with spherical ends which are
fitted to suitable receptacles formed in the mace. The outer ends of these cranks
or arms are carried by globular bearings working in brackets which are at liberty
to rise and fall or turn to any angle or into any position to suit the throw of the
cams or eccentrics, and are fitted with springs or buffers for adjusting the pressure
of the runners on the pan. The motion is imparted to the said runners by the
revolving pan coming in contact with them; and the vertical shaft, at the same
time, imparts motion to the cams or eccentrics which cause the mace to work in
and out according to the amount of the throw of the cams. The runners revolve
on their arms and are kept in position by collars or the like. As they are fixed to
the mace, they work in and out at the same time, thereby causing a continuous
scrupping or grinding, in addition to the well known crushing, motion of the
runners.
The runners are made of hard chilled iron, or any other suitable material, with
flat or concaved faces, and revolve on a renewable path made of cast steel, or any
other suitably hard material, with a flat or convex surface to correspond. The
latter may be made in segments fixed to the pan.
The mill may be fed at any part; and the stuff to be ground may be distributed
by means of adjustable scrapers fixed to the mace, by which means it is kept in
constant agitation.
The stuff when ground will pass off the pan by centrifugal force and under an
adjustable ring or other suitable device placed near the periphery of the pan.
The latter is fitted with various scrapers for passing back to the runners, the
stuff not sufficiently ground. The ground stuff after passing under the ring,
passes over the edge of the pan and falls into a receptacle from which it is
collected or expelled by means of scrapers fixed to the under part of the outer
edge of the pan.
Our invention includes the application of the cam or eccentric mechanism above
described as for imparting the scrupping or grinding motion and action, to the pan
instead of to the runners of an edge runner grinding mill.
Our invention further includes the application of the said cam or eccentric
mechanism for imparting the scrupping or grinding motion and action to grinding
mills in which the work is effected by burr stones or discs mounted in any plane.
In order that our invention and the means by which it is to be carried into

page_text: practical effect, may be thoroughly understood, we will now describe it and chem
in detail, referring in so doing to the accompanying drawings which are to be taken
as part of this Specification and read therewith.
Figure 1 is a front elevation partly in section.
Figure 2 is a sectional plan taken on the line 2-2 of Figure 1.
Figure 3 is a sectional front elevation taken on the line 3-3 of Figure 4.
Figure 4 is a sectional plan taken on the line 4-4 of Figure 3.
Figure 5 is a front elevation of Figure 4-looking at it in the direction of the
arrow-shewing the casing of the grinding mechanism in section.
Figure 6 is a sectional elevation taken on the line 6-6 of Figure 4.
Figure 7 is a vertical section of a vertical disc mill.
Figure 8 is a vertical section of a horizontal disc mill.
Figure 9 is a sectional elevation of a substitute type of adjustable step bearing.
Figure 10 is a horizontal section on the line 10-10 of Figure 9.
Figure 11 is a sectional elevation of a modified form of ball bearing.
Figure 12 is a plan thereof.
Referring to Figures 1 and 2 the mill illustrated therein is an edge runner with
a revolving pan constructed according to the present invention. The usual pan is
replaced by a flat plate a which may be of any suitable construction. It is shewn
as consisting of several segments bolted together. The annular surface upon
which the crushing and grinding is effected, is provided by a renewable ring a.
The plate a and ring a' are hereinafter referred to as the "pan." The pan is
made fast in the horizontal plane, as heretofore, to a vertical shaft b which is
carried in suitable bearings. The top bearing b¹ is carried by the frame of the
mill. The bottom one is described further on. The driving gear may be of any
suitable kind. It is shewn as consisting of a rope pulley on a countershaft 6,
a mitre pinion 6' and a crown wheel 68. The latter is fast on the top of the vertical
shaft b. Provision is made for putting the mill in and out of work, by connecting
the pinion to a handwheel 6' concentrically with it in such a way that either can
be rotated independently of the other, but so that neither can be moved along the
countershaft without the other. This handwheel is bored out and screwed to
engage with a screw thread 68 on the countershaft. The latter is carried in
hearings in pillow blocks 6º, 6 bolted on the top of the frame of the mill. The
top bearing b¹ is supported by the said frame while the bottom one, 62, is a step
c is the box of
bearing of special construction standing upon the bed of the mill.
this step bearing and c¹, a toe held in a central position therein by a ring c². The
end of the shaft 6 is fitted with a concave button c³ up to which the toe is kept by
a wedge c* which can be moved longitudinally in either direction across the bottom
of the box c and through its side, by the wedge-shank which serves as a handle
for that purpose. The function of the wedge c being to provide for setting up
the toe c', provision is made for holding the wedge in any given position with
reference to the height at which it holds the toe, by means of two lock nuts c* on
the shank co, one on each side of a tab c' through which the said shank passes.
d, d are antifriction rollers supported by pillow blocks & standing on the bed of
the mill. Their function being to support the pan against the weight of the
Access to the step bearing,
runners, they are placed, centrally under the ring a¹.
as well as to the rollers d, is provided by a way d² in the bed. This way is
indicated by dotted lines in Figure 1. e, e, e, e are four edge runners. They may
be of any suitable material, and are fitted with bushes e¹. e², e², e², e² are their
shafts. A runner is held to its shaft by a pair of dust collars e³, e³. These
respectively embrace rings et, et on the sides of the runner and are made fast to
the shaft by any suitable device. e, e are antifriction collars inserted between the
outer dust collar e and ring e. The outer end of each shaft e² has its bearing in
a sphere which is carried between two plates f,f, both suitably concaved on
their respectively adjacent faces for it to fit in. This method of supporting the
sphere provides for it being moved in any direction about its centre. The spheref
and plates f, f are capable of a vertical motion in either direction in a slot in the

page_text: column. The plates are kept up to the sphere, and all three returned to their
normal position in the slot, by a pair of spiral cushioning springs f³, one above
and one below the sphere. The bottom spring f³ acts between the base of the
column and the underside of the plate, and the top one between the upper
side of the plate f* and a plate f³. f is a set screw adapted to work through
the top of the standard down upon the plate f for the purpose of regulating
the tension of the pair of cushioning springs. f' is the locking nut of the said
set screw.
g is an eccentric fast upon the shaft b, the axis through the centre from which it
is struck being parallel with the axis of the said shaft. Its function is to, in
combination with a special device by which the inner end of each runner shaft is
held to the shaft, make the runners grin.l or scrup the stuff. upon the pan, in
addition to crushing it, as it is carried under; and, provided that this grinding or
scrupping action is duly provided for, our invention does not limit us in respect of
the detailed construction of such eccentric, or whether there is used an eccentric
or a cam or a combination of both. The ring or strap of the eccentric, as well as
the bearings for the inner ends of the four runner shafts, are all merged in the
mace h. This latter is bored out to fit the periphery of the eccentric, a suitable
bush being interposed. 1, h2, h3, h², are four cups formed in the mace at equal
distances from the geometric centre of the eccentric, and with their centres in the
same horizontal plane as that of the axes of the runner shafts e. The inner end
of each shaft has a ball e formed upon it of a proper size to fit and turn smoothly
in its respective cup 2. The opening into the cup, i.e., the open side of the cup,
is larger than the runner shaft by about one half for two reasons, first, in order
that the shaft may pivot vertically as the inequalities in the thickness or consistence
of the stuff on the pan, cause the runners to rise and fall; and, second, in order
that the inner end of the shaft may follow the eccentric. Each cup is provided
with a flaring mouth 3 which strengthens the opening into the cup and serves as a
stop to the respective shaft. The mace is split centrally in the horizontal plane to
allow of its cups embracing the balls e, the two halves being held together by
bolts. It is, further, held at its working level on the eccentric by a pair of
combined holding rings or nuts h and dust guards . Each nut is made in two
halves for convenience in fixing, and is held to the eccentric by a screw thread
in order that the position of the mace upon the cam may be adjusted.
friction ring is interposed between each nut and the mace.
An anti-
i is a vertical metal ring, rather smaller (if anything) in diameter than the
pan a.
It is held over the latter by brackets which are fixed either to the bed
of the mill or to the columns f2. Provision must be made for adjusting the distance
at which the ring i stands clear of the surface of the pan, because it is that
distance which will be the gauge to which the stuff is to be milled. We do not
confine ourselves to any particular device but suggest the use of vertical slots in
either the ring, or the brackets, and nutted bolts passed through both. Further,
the ring i may be made either in one piece or in segments, as may be preferred.
jj are the central, and j', j', the outside, diverters. The former are supported by
the mace and the latter by the ring i.
k is a circular trough under, and projecting beyond, the pan a. k¹, k' are scrapers
supported in the said trough by tabs k² on the periphery of the pan. ³ is the
shoot from the trough. It is constructed in the bed of the mill and is indicated
by the dotted lines in Figure 1. The trough opens into it through its floor and
outer wall. is a casing provided for the purpose of keeping the dust in.
Our invention constructed as above described works as follows. The ring is
first adjusted. As soon as the pinion 65 is in gear with the crown wheel 6, the
pan a begins to revolve and to rotate the runners, as heretofore, but in addition to
this motion of rotation on the part of each runner in a vertical plane about a
horizontal axis both plane and axis being stationary, relatively to each other-
each runner is at the same time compelled to grind or scrup over the pan, the
direction of the grinding or scrupping motion being elliptical. The effect of the

page_text: 65
combination of the two motions is that the stuff, no matter what may have been its
condition when it was fed into the pan, is first crushed and then ground and floured
(ie., scrupped) being thereby reduced to an impalpable powder or fine grained paste..
The production of the said elliptical motion between the two contacting, and
therefore operative, surfaces of the mill is the distinguishing feature of the process
of grinding as conducted in a mill made according to the present invention. By
contacting and operative surfaces of the mill" we mean the peripheries of the
runners and the surface of the pan, or the corresponding surfaces of a pair of burr
stones or a pair of discs. Each runner makes one elliptical motion upon the pan
during one revolution of the latter. It is the interposition of the eccentric and.
eccentric strap (or their equivalents, respectively) between the central shaft on the
one side and the sockets of the inner ends of the runner shafts on the other side,.
that is the agent by which the novelty in the process is effected.
As the pan revolves, a centrifugal motion is imparted to the stuff, and those solid
portions of the latter which are reduced to the desired gauge (which is the distance.
between the ring i and the pan a) pass under the ring and drop into the trough k
from which it is driven by the scrapers k¹ into the shoot k³.
We do not confine ourselves in respect of an edge runner made according to the-
present invention, to making the pan rotary and the runner shafts non-rotary and
moving elliptically; for it is evident that an edge runner in which the runner
shafts e² are fast to the central shaft b, and the pan a to the eccentric strap, is as
much according to our invention and within it as the one illustrated in Figures 1
and 2 and described therewith.
Figures 3 to 6 illustrate a mill constructed according to the present invention and
mounted on a Mill Hurst framing. The consequent modifications are unimportant
and will be readily understood from an examination of the figures in question.
The step bearing of the shaft 6 is carried by an arch k. The handwheel 6' and
screw thread 68 are transferred from the countershaft to the vertical shaft. The
pillow blocks d and antifriction rollers d are dispensed with because they are not
required in the small sizes of mills which will be made according to the modification
now under specification. The shoot takes the form of a spout.
Referring to Figures 7 and 8, j, j are a pair of parallel grinding discs. Their-
operative surfaces are made of suitable material. The former is in each case keyed
fast to the shaft b. The latter, j', is connected to the eccentric 9 by a vertical
socket g' which is made fast to the disc and, therefore, serves as an eccentric strap..
92 is a cushioning spring between the holding ring hand the antifriction ring h³..
The holding ring is prevented from moving out of its adjusted position on the
thread on the eccentric, by a set screw g³ adapted to hold a segmental piece y¹
incorporated with the ring, up to the said thread. 9 is a dust ring held to the
ring by the set screw g³. 9' is the feeding hopper.
Referring to Figures 9 and 10, c is the box of the bearing and c', its toe. The
button is flat as to its bottom face instead of being convex, and the top face of
the toe el is also flat. Further, it has an annulus 8 (of smaller diameter than that
of the button c³) and which is provided with balls c, thereby providing a ball,-as-
distinct from a step,-bearing. The base of the toe c is slotted, as indicated by
the dotted lines, to straddle the wedge e; and the box c is slotted through both
sides.
Referring to Figures 11 and 12, the ball stands in a conical seating, the base
of which stands within the box c and rests upon a spiral spring held within the
said box and within which it can rise and fall. 1, 12 are bolts which, by engaging.
with lugs, are adapted to hold the seating to the box without interfering with its.
vertical motion.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
I 'Thu can hination of
chaf
L

page_text: connected to one of the contacting and operative surfaces of the mill, as set:
forth.
2. The combination with the pan on to which the stuff is fed, in an edge runner,
of eccentric fast on the shaft and eccentric strap fast to the said pan, as set forth.
3. The combination of shaft, eccentric fast thereon, eccentric strap and mace,
cups therein, and edge runner shafts engaged by one end in the said cups and by the
opposite ends in spherical bearings free to rise and fall vertically, as set forth.
4. The combination with the mace, of spherical cups formed therein and adapted
to receive and hold the ball shaped ends of the respective edge runner shafts, as
set forth.
5. The combination in a grinding mill, of a pan on to which the stuff' to be
ground is fed and which pan is revolved in the horizontal plane, and a concentric
gauging ring stationary with respect to the said pan and adjustable vertically with.
reference thereto, as set forth.
6. The combination with the pan of a grinding mill adapted to be revolved in
the horizontal plane, of a concentric gauging ring and diverters fast thereto, both
stationary with respect to the said pan and adjustable vertically with reference to
the said pan, as set forth.
7. The combination of shaft, eccentric fast thereon, eccentric strap and mace,
cups therein, edge runner shafts engaged by one end in the said cups and by the
opposite ends in spherical bearings free to rise and fall vertically, edge runners,
pan on to which the stuff is fed and a concentric gauging ring stationary with
respect to the said pan and adjustable vertically with reference thereto, as set
forth.
8. The combination of shaft, eccentric fast thereon, eccentric strap and mace,
cups therein, edge runner shafts engaged by one end in the said cups and retained
therein and by the opposite ends in spherical bearings free to rise and fall vertically,
edge runners, pan on to which the stuff is fed and a concentric gauging ring
and diverters fast thereto, both stationary with respect to the said pan and
adjustable vertically with reference thereto, as set forth.
9. The hereinbefore described construction of grinding mill adapted to subject
the stuff to be ground to a combined crushing and scrupping action, as set forth.
Dated this 19th day of January 1894.
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicants.