Year: 1887

page_text: Date of Application, 8th Nov., 1887
Specification Accepted, 20th Jan., 1888
1, WILLIAM FRAZER COCHRANE, residing at Cambridge City in the County of
Wayne, and State of Indiana, one of the United States of America, Gentleman, do
hereby declare the nature of this invention and in what manner the same is to bo
performed to be particularly described and ascertained in and by the following
statement :-
My invention relates to and comprehends certain improvements applicable more
especially to a roller mill system of the kind described in patent No. 11584, dated
September, 29, 1885, that is to say, a system wherein a series of pairs of rolls are
arranged in line and driven directly from a shaft or pulley common to the whole series,
thereby dispensing with the complicated and cumbersome system of driving mechanism
comprising counter shafts, pulleys, belts and belt tighteners, which had previously
been employed and.deemed essential to the practical and successful operation of a
series of pairs of rolls used in the gradual reduction process of milling.
The said invention comprises an improved system of driving mechanism for the
grinding rolls, driving mechanism for the feed rolls, and adjusting and relief
mechanism for the grinding rolls; as well as certain minor improvements in the
construction, arrangement and combination of the various elements, the whole
contributing to the formation of a complete roller mill, all as hereinafter described
and claimed.
Figure, 1, is a plan view, showing a portion of a train or system of rolls, the casings
being omitted.
Figure, 2, is a front elevation with hoppers and casings in position.
Figure, 3, is an end view partly in section of a double set or pair of rolls.
Figure, 4, is a longitudinal section through one of the feed rolls and its driving
mechanism.
Figure, 5, is an enlarged view, partly in section of the flexible coupling. for
connecting the grinding or crushing rolls.
Similar letters and figures in the several figures of the drawings denote corre--
sponding parts.
In illustrating a practical embodiment of my invention I. have represented the
[Price 8d.]

page_text: series of pairs of rolls as mounted upon my improved frame, composed of the two
longitudinal beams or girders, A, preferably of angle iron as shown-united at intervals
by cross pieces, B, of less depth than the girders, A, and arranged in pairs to constitute
supports for the journal boxes of the rolls.
Each set or pair of rolls comprises a fixed roll, C, that is to say, a roll whose
bearings, c, though adjustable are fixed in position when the mill is in operation and
a movable roll, C, whose boxes, c¹, are movably supported upon the cross pieces B,
and held in position by an adjustable and yielding tension mechanism.
The several sets or pairs of rolls constituting a series are arranged in line, that is
to say, one roll of each set is in the line with one of the rolls of the next succeeding
set and although not essential that it should be so, I prefer, for obvious reasons, to
arrange all the fixed rolls in one line and all the movable rolls in another but parallel
line.
The journals of the rolls are continued or projected beyond their boxes to receive a
section of a flexible coupling device, 1. Said section being preferably made in the
form of a disk or head, 2, provided with an annular series of teeth 3, or an equivalent
form of interlocking projection, for engaging the teeth of a corresponding section, 4,
mounted upon the end of a section of shafting, 5.
One of these shafts, 5, forming part of the flexible coupling device, is interposed
between the contiguous ends of adjacent rolls, the ends of the shaft being supported
loosely in bearings formed in the centre of the disks, 2. The coupling section, 4, on
one end of the shaft, 5, is attached so as to rotate with the latter, while the opposite
section fits loosely upon the shaft, 5. This loose coupling although free to rotate upon
the shaft and have a limited longitudinal play is restricted in its inward movement by
a collar or projection on the shaft, such for example as is furnished by the end of the
key or spline, 6.
The rear side or end of the loose coupling section is formed or provided with a
series of clutch teeth, preferably of the character described and claimed in my prior
patent No. 11584 of 1885 the cooperating clutch section, 7, being mounted upon the
shaft, 5. A collar or hub, 8, secured to the shaft and overlapping so as to embrace
the rear end of the clutch section encloses a spring, 9, which, as thus located and
arranged, serves the double purpose of holding the clutch section, 7, pressed towards
or in engagement with the loose coupling section, and being interposed between a
shoulder fixed to the shaft, 5, and the movable or loose coupling section, it serves to
hold the two coupling sections, 4, pressed apart so that they will be held firmly in
engagement with the coupling sections, 2, on the rolls thereby maintaining a tight
connection and at the same time permitting a limited lateral movement of the
rolls.
.
These two operations are distinct in character notwithstanding the fact that in the
embodiment shown they are the product of a single spring for, as is obvious if the
clutch section were removed or when the clutch is engaged, the spring operates to
force apart the coupling sections and if on the contrary, the coupling sections were
not separable, the spring would operate in the same manner, to throw the clutch
sections together and hold their ends in yielding engagement while starting up the
roll, hence when claiming the spring in combination with the movable sections of a
coupling device, I do not wish to be understood as including therein the clutch unless
specified as an element in the claim.
When connected together by coupling devices of the character described, each line
of rolls can be driven by the application of the driving power at any desired point in
the line but usually I prefer to locate the driving, mechanism at one end of the series
of rolls, and support said driving mechanism in a framework attached to or forming
part of the main frame.
I prefer to drive the series of rolls by a belt, and in order that a single pulley or
wheel shall be made to perform this operation, the following arrangement is
recommended :-
A shaft, 11, carrying a pulley, 10, is mounted in bearings 12, in line with one line
of rolls, the end of said shaft being provided with a coupling section, 13, corresponding

page_text: to that on the journals of the rolls.
pinion or wheel, 14, on this shaft, 11,
communicates motion through a gear or wheel, 16, to a counter shaft, 17, which latter
is mounted in bearings 12, and carries a coupling section cooperating with the second
line of rolls:
This arrangement of driving mechanism with flexible couplings interposed between
the successive rolls in each line possesses these advantages. Power applied to the
driving pulley will cause the simultaneous rotation of all the rolls in both lines and in
the proper direction for grinding; any one or more of the rolls can be moved or
adjusted even while in motion, and with respect to the cooperating roll in the other
line or the contiguous rolls in the same line, without disturbing the driving connection
which latter readily accommodates itself to the lateral movement of the rolls; the
flexible couplings are at all times held tight by the spreading action of the springs so
that excessive wear and lost motion and the noise consequent thereon is avoided.
As is well understood the cooperating rolls of each set or pair when used for
grinding, are required to have different peripheral velocities while the absolute as well
as the relative surface speed of the rolls in the several sets or pairs constituting the
system are subject to wide variations.
In order to produce this result, which is an essential element in a system of the
kind described, the wheels, 14, and, 16, through which motion is communicated frou
one line of rolls to the other, are made of different diameters: this will cause the
rolls in one line to rotate in unison but at a more rapid rate than those in the other
line. If now the several rolls are constructed of different diameters, the diameter of
each roll being proportioned to the speed of the line in which it is located, any
desired peripheral velocity cam be obtained.
Practice has demonstrated that when driving a series of pairs of rolls at the high
rates of speed necessary for milling a great saving, of power is effected especially in
starting the mill-if the driving power is applied to the line of rolls making the greater
number of revolutions.
In the illustration I have shown the driving pulley applied to the front suries of
rolls which are designed to rotate say at 400 revolutions per minute, while the rear
line of rolls rotate at 300, to accomplish which the gears or wheels 14, and, 16, are
made of the proper proportional diameters, the smaller gear being secured to the
driving shaft.
By so doing not only, is the mill more easily started but the noise of
the gears is greatly subdueil.
As before stated the bearings, c', of the movable rolls, C', are not fastened in position
upon the cross pieces, B, but are designed to be held in position by an elastic tension
device which, while holding the roll to its work, will permit it to yield, should
excessive pressure be brought to bear.
The tension and adjusting mechanisms as ordinarily constructed are usually applied
to the front roll, (especially when two sets of rolls are mounted in the same frame) and
as the pressure exerted on the material passing between the rolls is very great and
reacts upon the rolls in a direction to force them apart, the tension and adjusting
mechanism is necessarily heavy and cumbersome and when levers are employed to
act upon the bearings of the front roll, they occupy much valuable space besides
compelling the elevation of the rolls above the floor line. With a view to overcoming
these and other defects in prior adjusting and tension mechanisms and at at the same time
furnish a simple and efficient mechanism for the purpose, occupying but little if any
space otherwise available, I locate the movable roll in the rear instead of the front,
and carry the actuating lever across the machine.
The preferred, though not the only arrangement of device for utilizing this feature
of my invention is shown in the drawings, wherein the boxes or bearings for the
rolls C are each provided with a dependent lug, 21, suitably notched or slotted for
the reception of a pin, 23, carried by a collar, 24. The collars, 24, are adjustably
secured to a shaft, 25, which has its bearings in the cross pieces, B, below and in rear
of the journals of the roll, C.
To the shaft, 25, is secured a lever, 20, extending across and preferably below the
rolls, C, C, with its outer end projected through a slot or opening in the front plate

page_text: or girder A, of the frame. The tension and adjusting devices are applied to the
front or outer ends of this lever where they can be conveniently manipulated. Thus
in the machine shown, the outer end of the lever, 20. carries a spring case, 26,
pivotally secured thereto while a spring, 27, located within the said casing and com-
pressed between the latter and a fixed abutment operates upon the lever in a direction
to hold the roll, C, to its work. To provide for regulating the pressure of the spring
and in addition thereto afford a means for effecting an instantaneous release or
application of pressure the upper end of the spring instead of bearing against a fixed
abutment engages a collar or cross head, 28, on a screw, 29, the latter passing through a
nut, 30, which is restrained from rotation by engaging the face of the guide while
a hand wheel, 31, fitting loosely upon the screw is connected to rotate the latter as by
a groove and feather or equivalent connection.
Between the horizontal flange of the girder, A, (or other abutment through which
the screw is passed) and the nut, 30 is arranged the relief device, composed in the
present instance of two sections, 32, 33, having cooperating inclines or cams, 34.
The cam section, 32, is held from rotation as by its engagement with a shoulder or
projection or by being secured to the flange of the girder; while the section, 33,
carrying a suitable handle is free to rotate on the screw.
When the section, 33, is rotated in a direction to cause the opposing cams or inclines
to ride up on each other, the nut, 30, will be forced down, the screw advanced and the
spring compressed against the lever. This is the working position and the adjustment.
of the spring is effected while the two cam sections are at the extreme point of
separation where they are retained by the points of one series of cams becoming
seated in recesses, 35, in the opposite cams.
When it is desired for any purpose to instantly relieve the spring and thus withdraw
the pressure on the movable roll the section, 33, is turned back or in a direction to
cause the opposing cams to move down upon each other thereby withdrawing or
retracting the support for the nut and permitting the spring to expand at the outer
end. In taking the pressure off, the movement of the section, 33, is assisted and
expedited (as soon as the points of the cams are forced out from the locking recesses)
by the pressure of the spring.
It is my intention in practice to mount two series each composed of two lines of
rolls, upon a single frame but as they are duplicates in the construction and arrange-
ment of parts I have described but one series though two are indicated in the
drawings.
Each pair of rolls is provided with the usual or any approved enclosing casing with
a hopper beneath the rolls for the reception of material passing between them and a
hopper above provided with an adjustable gate and feed roll, 40.
The several feed rolls of the series are arranged in line each roll being provided
with journals, 41, at opposite ends which are received and supported in journal boxes
or collars 42, on the sides of the hoppers. Each roll, 40, is perforated longitudinally
and centrally for the accommodation and support of a shaft, 43, and upon the latter
is mounted a sliding clutch section, 44, adapted to engage a clutch section, 45, on one
journal of the roll. A shipper, 46, and a spring, 47, are provided for shifting the
clutch section, 44, to start or stop the roll.
As it is extremely difficult to establish and maintain all the feed rolls in exactly the
same line so they might be driven from a single shaft and as to do so would
necessitate frequent and troublesome adjustments of the bearings, I have provided
each roll with a short section only of shafting (resting loosely within the roll and
connected thereto when desired by the clutch) and I connect the proximate ends of
the contiguous sections, 43, by what is herein termed a wabler or Hexible connection
which is or may be constructed and applied as follows:-
To the ends of the shafts, 43, are secured heads or collars, 50, baving their outer
faces grooved or provided with one or more transverse ribs as shown and between
said collars is interposed a short section of shafting, 51, the ends entering and resting
within the central openings in said collars.

page_text: .
At or near each end of the shaft, 51, is secured a collar 52, provided with inter-
locking projections for engaging the collars, 50. The connection thus made between
the shaft sections, 43, and, 51, is such as will readily perinit and accommodate a limited
degree of lateral movement or the angling of either roll without interfering with their
rotation, so that if the feed rolls are set a little out of line or askew it will not
interrupt or impede their rotation. By thus arranging and connecting the driving
shaft of the feed rolls, the whole series can be driven at once and by a single applica-
tion of power each feed roll can be connected or disconnected from the driving
mechanism without interfering with the others and any one or more of the feed
rolls can be removed and a longer wabler section inserted in its place.
Although i have shown in the drawings a portion of the casing and feed adjusting
devices, as they do not constitute material elements of the invention claimed herein
and can be omitted or changed at will, I have not deemed it expedient to describe
them.
It is to be understood that some adequate means such as a set screw, 50, in the
bearings, c, of each movable roll, C, is to be supplied for preventing the rolls coming
in contact and adjusting their positions relative to the fixed roll, C.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is :-
1. The combination in a system such as described and with the series of feeding
rolls, of flexible driving connections or wablers interposed between the ends of con-
tiguous rolls and a driving mechanism or pulley common to the whole series,
substantially as described.
2. In a system such as described and in combination with a series of grinding or
crushing rolls a series of hollow feed rolls, each supported in bearings and a sectional
driving shaft extending through the series of feed rolls and flexible connections
uniting the contiguous ends of the shaft sections substantially as described,
3. In a system such as described and in combination with the series of hollow feed
rolls and the sectional driving shaft extending through said feed rolls and united by
flexible couplings or wablers a series of clutch sections niounted on the driving shaft.
each adapted to engage a clutch section on one of the rolls substantially as described.
4. In combination with a hollow feed roll mounted in bearings secured to the sides
of the hopper or casing, the clutch section attached to one end of the roll, a sliding
clutch section with spring and shipper, and a driving shaft passing through the clutch
sections and hollow rolls and having its bearing in the latter substantially as
described.
5. In a system such as described and in combination with the series of hollow feed
rolls supported in independent bearings and each provided with a clutch section, a
driving shaft for each roll extending through the latter and carrying a clutch section
cooperating with that on the roll, and a shaft interposed between the proximate ends
of the contiguous roll driving shafts and connected to the latter by collars having
interlocking projections, substantially as described.
6. In a roller mill such as described and in combination with the movable bearings
supporting the rear roll an adjusting lever for actuating the bearings of the movable
roll, said lever being extended across to the front of the frame substantially as
described.
7. In a roller mill, such as described, the combination with the front roll mounted
in stationary bearings and the rear roll in movable hearings a lever engaging said
movable bearings and extended across from the rear to the front of the frame and
a tension device interposed between the frame and the end of the lever, substantially
as described.
8. In a roller mill such as described, and in combination with the movable bearings,
carrying the back roll the rock shaft pivotally supported in rear of and below said
roll and connected to the bearings and the actuating lever secured to the rock shaft

page_text: and extending beneath the rolls and through the front of the frame, substantially as
described.
9. In a roller mill such as described, and in combination with the bearings of the
adjustable roll and the pivoted actuating lever engaging said bearings, the spring, the
adjustable collar and an expansible connection interposed between the lever and a
stationary part of the frame, substantially as described.
10. In a roller mill such as described and in combination with the bearings of the
adjustable roll and the actuating lever extended across and projected beyond the
front of the frame, a tension spring interposed between the end of the lever and an
adjustable bearing or plate and a cam engaging said bearing to compress the spring
for holding the roll up to its work and to relieve the pressure and permit the roll to
yield, substantially as described.
11. In a roller mill system such as described, and in combination with a series of
pairs of rolls one member of each pair mounted in movable bearings and the rolls of
each set varying in diameter proportionately to the speed of the driver to produce the
desired differential peripheral velocities, the flexible couplings or wablers interposed
between and connected to the ends of contiguous rolls, substantially as and for the
purpose set forth.
12. In a system such as described and in combination with the two parallel lines of
rolls arranged in sets, the corresponding rolls of all the sets being in the same line, a
driving pulley or gear connected directly in the line of rolls rotating at the higher
speed, a counter shaft or its equivalent connected directly in line with the series of
rolls rotating at the lesser speed, and a gear on the quick line, meshing into a larger
gear on the counter shaft in the line of the slower rolls, substantially as described.
18. In a system such as described, wherein a series of pairs of rolls are arranged in
line, the corresponding rolls of each pair being driven at the same speed and the front
and rear rolls at different speeds, the rolls of each pair varying in diameter to produce
the desired differential surface movement, and in combination with said series of rolls
and the bearings in which they are supported, a flexible coupling interposed between
the proximate ends of contiguous rolls in each line, a driving gear or wheel for each
line of rolls and a pulley or main driver applied to one line of rolls and communicating
motion to the other through the first mentioned driving gear or wheels, substantially
as described.
14. The combination in a system such as described and with the contiguous rolls of
the series, mounted in boxes and arranged end to end in line, the coupling sections
secured to the ends of the rolls, the interposed shaft carrying a fast and a loose coupling
section and the movable clutch section mounted on the shaft and engaging a clutch
section connected to the loose coupling section substantially as described.
15. In a system such as described and in combination with the series of pairs of
rolls arranged in line a flexible coupling interposed between the proximate ends of
contiguous rolls and a starting clutch substantially such as described for connecting
the flexible coupling and roll, as and for the purpose set forth.
Datel this 8th day at Navumbar 1987