Improvements in Roller Crushing Mills, partly applicable to Calender- ing Machines, Rolling Mills, and similar Machines in which Rolls are employed.
Year: 1898

page_text: Date of Application, 12th Apr., 1898-Accepted, 27th Aug., 1898
Improvements in Roller Crushing Mills, partly applicable to Calender-
ing Machines, Rolling Mills, and similar Machines in which Rolls
are employed.
I, BENJAMIN JOSEPH BARARD MILLS, of 23, Southampton Buildings, in the
County of London, Patent Agent, do hereby declare the nature of this invention
(a communication to me from Thomas Alva Edison, of Llewellyn Park, in the
County of Essex, and State of New Jersey, in the United States of America,
Inventor,) 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 machines for crushing ore, calendering paper, rolling
iron, crushing sugar cane, and for similar purposes. The principal objects of the
invention are, first to diminish the power required to drive the rolls; second, to
obtain enormous pressures between the rolls; and finally, to effect various improve-
ments in matters of detail.
and
The accompanying drawings illustrate the improved rolls especially arranged for
crushing ore. Fig. 1 is a front elevation with the casing, hopper etc. removed;
Fig. 2 a section on the line 2-2 of Fig. 1; Fig. 3 a horizontal section through
a portion of the top or bottom roll and through the housing
shaft; Fig. 4 a sectional view on the line 44 of Fig. 3; Fig. 5
a section on the line 5-5 of Fig. 3; Fig. 6 an elevation partly in section
of one end of the driven shaft and wobbling coupling; Fig. 7 a sectional view on
the line 7-7 of Fig. 6; and Fig. 8 a section of one roll.
A, A¹ represent the housings, and B, C, D three rolls arranged in line with their
shafts carried in movable bearing blocks E. The shafts of rolls B, D extend
beyond the bearing blocks and carry at each end a number of separate grooved
sheaves F. A wire rope G passes around the four sets of sheaves, the two bights
being carried by suitably supported wheels H, H, I, I. Starting at a point
between wheels H, H (see Fig. 1) this rope passes over wheel H, downwardly
to and around the innermost sheave on the left of the shaft of roll 3, thence
upwardly to and around the corresponding sheave of roll D, thence downwardly
and around the second sheave below, and so on until the outermost sheave of the
lower shaft is encircled, when the rope extends upwardly and over the wheel I,
thence to the wheel I', thence downwardly around the sheaves on the right hand
ends of the shafts or rolls B and D, from whence it returns over the wheel H¹ to
the imagined point of starting. It will be seen that the sheaves at each end are
coupled together like the sheaves in a compound block and tackle, a single wire
rope being used. The bight of the rope between wheels I and I¹ passes over
another wheel J carried by a piston rod of a piston located in a cylinder K. From
the lower end of this cylinder a pipe a extends to a source of fluid pressure, such
as air or steam, and is provided with a throttle valve b, a gauge c and a safety
valve d.
With the existing type of roller crushing mills, calendering machines, rolling

page_text: '
mills and the like, pressure between the rolls is obtained by stress exerted upon
the bearing boxes, whereby enormous friction is developed. With this invention,
the total weight of the rolls is carried by the bearings of the bottom roll B. The
rolls are therefore made as light as possible. The fluid pressure in the cylinder K
tightens the wire rope, producing a pressure which is multiplied on the principle
of the compound block and tackle. Assuming ten turns of the rope at each end
of the machine and a pressure of 3,000 kilograms on the piston, then the stress on
the rolls will be 60,000 kilograms.
By regulating the pressure in the cylinder, the pressure between the rolls can
be adjusted while the rolls are in motion. It will be observed that slight driving
power is required, since the pressure is not produced upon the bearing blocks. This
will be clearly seen if the rolls are imagined supported in mid air on the ropes
themselves.
By using separate sheaves, the gang of ropes holding the rolls together may
shorten or lengthen as the rolls accommodate the material. The lower roll B is
positively driven by a shaft L, the other rolls being driven by friction of the
co-acting surfaces. An elastic fluid under pressure is preferable to weights to
obtain pressure, although the latter might be used where sudden lateral movements
of the rolls are not experienced. While it is preferable to use a single endless
wire rope, since the pressure at both sides will be automatically equalized, yet a
separate rope and cylinder may be used at each side of the machine.
Instead of using three rolls, any other odd number may be employed, the top
and bottom rolls being connected by the wire rope.
When an even number of rolls are used, the rope or ropes will be crossed at each
side of the machine, so that the top and bottom rolls may rotate in opposite
directions.
The sheaves F are held on the shafts by collars e (see Fig. 3) bushings f of
phosphor-bronze being preferably employed. The sheaves are lubricated through
a hole y having radial passages (see dotted lines, Fig. 3). The bearing blocks E
are provided with removable bushings h lubricated through an oil hole i (see Fig. 6).
The inner end of each bearing block carries an oil casing M having a drip-pipe h¹
(see Fig. 5.). Each shaft is provided with a thrust-bearing, as shown in Figures 3
and 4, comprising two grooves cut in the shaft, with split steel rings k working
therein, which rings are surrounded by a split collar N, N, held together by bolts (
and secured to the bearing block E by bolts m.
Each roll comprises a cast-iron cylinder O keyed to the shaft and carrying a
crushing shell P keyed to the cylinder by a key n. The shell is held against
lateral movement by bolts o carried in channels in the cylinder with their heads
and nuts engaging the adjacent edges of the cylinder and shell (see Fig. 8).
The shell Pis provided with a shoulder p engaging a corresponding shoulder 4
on the cylinder. In order to allow for slight lateral movements of the roll B, a
wobbling coupling Q, Q, is employed, the parts being secured together by brass
bolts made so small that if the rolls become clogged, the bolts will be sheared
off and the rotation of the rolls arrested. Each coupling section is made in three
parts (see Fig. 7) each part carrying a projecting lug engaging grooves s in the 4
ends of the shaft of the lower roll B and of the shaft L. The parts fit loosely
together so that motion is transmitted to the roll B without binding, even if the
shafts are not in line.
In crushing ore, a hopper R (see Fig. 2) is used having a roller feed S, an
adjusting board S¹ being used to control the thickness of the feed. Below the 5
roller feed is an inclined board t having a pivoted plate t¹ resting on the upper sur-
face of the roll C, said board and plate being carried by side pieces T hung on the
shaft of the roller S and supported at their lower ends by bolts 2. After passing
between the rolls C and D the material falls on a screen U, through which the
fine ore passes.
A chute u carries this fine ore to a conveyor belt V leading to any point. From
the screen U, the tailings pass upon a plate resting on the roll B, whereby the
5.

page_text: said tailings will be passed through the rolls B and C, from whence they also fall
upon the conveyor belt V.
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. A rolling machine comprising two or more rolls, the end rolls being provided
with independently mounted sheaves at each end thereof and one or more ropes
connecting said sheaves as explained, and a suitable pressure producing device con-
nected to the said rope or ropes, substantially as set forth.
2. A rolling machine comprising two or more rolls, the end rolls being provided
with independently mounted sheaves at each end thereof and one or more ropes
connecting said sheaves as explained, a suitable pressure producing device con-
nected to the said rope or ropes, and means for regulating the pressure of said
pressure producing device, substantially as set forth.
3. An improved rolling machine comprising three or any greater odd number of
rolls, independently mounted sheaves carried by the shafts of the outside rolls, an
endless rope or ropes connecting said sheaves as explained, a pressure producing
device for applying pressure to said rope or ropes, and a driving shaft connected
to one of the outside rolls by a wobbling connection, substantially as set forth.
4. An improved roll for a roller crushing mill, calendering machine, rolling
mill, or other like machine comprising a shaft, a cylinder keyed to said shaft, a
crushing shell keyed to said cylinder, and bolts carried in grooves formed in said
cylinder for preventing lateral movement of said crushing shell, substantially as
set forth.
5. An improved roller crushing mill comprising the three rolls B, C and D, the
hopper R, the roller feed, the chute for directing the material between the rolls C
and D, the screen U, and the plate for directing the tailings between the rolls B
and C.
Dated this 19th dose of An 1900
HARRIS & MILLS.
23, Southampton Buildings, London, W.C., Agents.