Improvements in or connected with the Rolls of Machinery for Mixing and Calendering India Rubber or other Materials.
Year: 1893

page_text: Date of Application, 7th Nov., 1893--Accepted, 23rd Dec., 1893
COMPLETE SPECIFICATION.
Improvements in or connected with the Rolls of Machinery for
Mixing and Calendering India Rubber or other Materials.
A communication from abroad by JOSEPH EDWIN DAVIS, of 34, Baltimore
Street, Lynn, in the State of Massachusetts, one of the United States of
America, Treasurer.
I ALFRED GEORGE BROOKES of 55 & 56 Chancery Lane, in the County of
London, Chartered Patent Agent, 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:-
In the mixing of india-rubber compounds, and in the subsequent steps of
calendering materials containing india rubber compounds, and other classes of
calendering machines, great difficulty is experienced because of undue heating
of the roll attributable to friction.
The rolls used for instance in machines for mixing india-rubber compounds are
now run at a very slow speed, usually from eleven to fifteen revolutions per minute,
and such rolls are cooled by a stream of water which is permitted to flow con-
tinuously, usually through a pipe at the centre of rotation of the roll, and then to
return to the same end of the roll around the said pipe, the water on its return flow
contacting for the first time with the body of the roll.
These rolls are usually from fourteen to sixteen inches in diameter, and the
diameter of the central opening is usually about two and three-fourths inches, thus
leaving a large body of metal which is acted upon at a very considerable distance
from its outer surface.
The water employed to cool these rolls is usually taken from a tank and its
temperature varies according to the weather so that in some weather it is almost
impossible to run the machine for any length of time without overheating and thus
injuring the stock, or else the machine is so run as to produce less work and
consequent beat.
It is no infrequent occurrence to have to stop a machine of the class referred to
for hours to let the rolls cool.
In his experiments to enable this class of machines to be run at faster speed, and
yet not overheat the rolls, my correspondent has devised a roll in which the cold
water entering it comes against the metal of the roll quite close to its periphery
where the heat is generated, and the water acts directly against the solid metal of
the roll in both directions of its flow.
Fig. 1, in longitudinal section represents a roll embodying the invention.
Fig. 2 is a section looking to the right of the line x, Fig. 1.
Fig. 3, is a section looking to the left of the line a¹, Fig. 1.
Fig. 4, is a section looking to the right of the line ³, Fig. 1.
Fig. 5, is a section through the journal of the roll in the line a³, but with the
collar removed showing the end of the body of the roll in elevation.
Figs. 6 and 7 are opposite end views of the full roll shown in Fig. 1.
Fig. 8 a vertical longitudinal section of a modified form of roll; and
Figs. 9 and 10 vertical cross sections of the same taken respectively on the
dotted lines ²x² and x-x².
The roll shown in Figs. 1 to 7 inclusive consists essentially of a body A having
suitable journals a, a¹, the ends of the journals being represented as having key
seats in order that suitable bevel gearing may be applied thereto, as in practice the
roll referred to will be geared in train with other like rolls between which the

page_text: material being acted upon is made to pass, and it is the friction between the rolls
and the material being acted upon which produces the objectionable heat in the
rolls which it is the object of this invention to overcome, undue heat in the roll
injuriously affecting the stock.
The roll shown is provided with a central opening b from end to end, and said
opening is subsequently closed near one end of the roll by a suitable dam, as b¹.
The body A of the roll is provided quite close to its surface with a series of
ports c, running, as shown, from one to the other end of the roll.
These ports, preferably substantially parallel each to the other, may be made in
a variety of ways, the cheaper method known to my correspondent being the
placing of a series of thin metal pipes in the mould in which is poured the metal to
form the body of the roll, said pipes being thereby incorporated with and so as to
form a solid portion of the roll, the pipes and the molten metal during the casting
operation being virtually welded together so as to leave unobstructed ports c
through the roll corresponding with the interior bore of the pipes.
My correspondent has in this embodiment of the invention arranged the ports so
as to work in groups of two.
Upon a reduced portion of the roll near the journal a is placed a collar d having,
see Fig. 2, a series of ports d' said collar being confined to the ends of the roll by a
series of screws or equivalents d', see Fig. 6 the said ports each being in communi-
cation with the ends of two of the ports c.
Going now to the journal a', a reduced portion of the roll near that journal is
provided, see Figs. 1 and 3, with a series of radial ports e, which communicate with
the central passage b in the roll, and at opposite sides of the dam b', the said
reduced end of the roll is provided with a series of ports f, see Fig. 4.
Outside the reduced portion of the roll having the ports e and fis mounted a
collar y provided with two annular ports or grooves at its inner side, as g¹, g², said
annular ports being in communication respectively with the ports f and e.
With the parts described, and as shewn in Figs. 1 to 7 the water entering the
roll in the direction of the arrow, Fig. 1, will travel through the centre of the roll,
and meeting the dam, will pass outwardly through the ports e, into the annular
port g from which it will be led by suitable openings into the ports.c, thence
across to the opposite end of the roll near the periphery thereof and into the port d¹
of the collar d, thence back through substantially parallel ports c, said second
ports c, being in communication by a passage y', see Fig. 4 with the annular port g'
and thence through the port finto the space at the centre of the journal at the other
side of the dam 6, and away to a suitable drain pipe or wherever the water may be
discharged.
The collar g is attached to the roll by a series of screws g³, see Fig. 7.
It will be noticed in the roll described that the water is passed through the body
of the roll not only at its centre but also very near its periphery where the roll is
the hottest and where the cool water has the greatest opportunity to reduce the
heat of the roll.
A roll having ports as described, for the passage of water in order that the roll
may be quickly cooled is valuable for many different classes of machines.
Instead of employing the collar d, each pair of pipes to form the peripheral
ports c may be connected together at one end by U-shaped elbows, such as used for
steam pipe work and the pipes so connected be put in the mould and be covered by
molten metal.
This invention is not limited to the exact construction or direction of the ports,
or to the exact shape of the ports in the collars referred to, so long as the water has
free run through and out of the roll.
It will be noticed that the roll A is an imperforate roll, and that it presents a
thick strong body of metal which stores up the heat generated by friction of the
roll on the material operated upon by it.
Where rolls are employed in the manufacture and rolling of rubber, it has been
found that the rubber always creeps towards the hottest parts of the rolls, and so

page_text: sensitive is the rubber to these differences in temperature that a difference in
temperature which is imperceptible to the touch may be detected by the tendency
of the rubber to creep towards a particular part or parts of the rolls.
In the rolls herein shown, however, it will be noticed that the peripheral ports
are connected in pairs or sets, the coldest water from the axial passage, for example
entering one of the peripheral ports at one end flows through said port to the
opposite end of the roll and back through its connected or return port to the end of
the roll from which it started.
By this arrangement a uniform temperature is maintained, the coldest water at
the entrance end of one peripheral port being balanced or offset by the warmest
water beside it at the outlet end of its return port, therefore, the uniform temperature
of the entire surface of the roll is a mean temperature between the hottest and
coldest water in adjacent peripheral ports.
In Figs. 1 to 7 inclusive the peripheral ports are shewn as extending longitudinally
the roll i.e., parallel with the ends of the same but this invention is not restricted to
such an arrangement of passages, for referring to Figs. 8 to 10 inclusive I have
shewn annular peripheral ports, i.e., ports arranged in planes perpendicular to the
axis of the roll.
Referring to said figs. M represents a solid metal roll provided with end
journals m, m.
N, N¹ represent respectively an axial inlet and outlet, the same entering the roll
through the journals at opposite ends, and extending nearly or quite the entire
length of the roll proper, and preferably being offset slightly within the roll as
shewn, in order that they may run parallel with and close to each other.
The roll shewn in Figs. 8 to 10 is, in accordance with this invention, provided
with a series of annular or circumferential circulating passages n, n, located
preferably close to the periphery of the roll and embedded therein, said passages in
the construction shewn being located in planes perpendicular to the axis of
the roll.
The annular circulating passages n. n, are each connected at, preferably,
diametrically opposite points with an inlet and outlet respectively, by radial inlet
and outlet pipes n', n³, the radial inlet passages in the successive annular passages
entering the latter at diametrically opposite sides of the roll, i.e., following the
entrance into the roll, the first radial inlet pipe leads from the axial inlet to the
right to the first annular passage, while the radial inlet in the second passage leaves
the axial inlet at the left, the third to the right, the fourth to the left and so on
alternately throughout the length of the roll; the alternate axial pipes likewise
leading to the axial outlet alternately from the opposite sides of the roll, the result
being that when a cooling fluid, as water, is introduced into the roll through the
axial inlet N said fluid will reach the first annular passage at one side the roll,
the second at the opposite side, and so on throughout the entire series of annular
passages, the flow of the fluid through successive passages being thus in opposite
directions from the coolest to the hottest parts of the passages, thereby obtaining a
uniform mean temperature between the hottest and coolest portions of the cooling
fluid, as in the construction Figs. 1 to 7 inclusive.
It matters not, of course, that annular circulating passages when used do not lie
in planes perpendicular to the axis of the roll, although such is the preferred
construction.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A metal roll having a series of peripheral ports; a central passage, and lateral
ports; a dam in said central passage; a series of ports at one end of the roll com-
municating with the peripheral ports, and a collar at the other end of the roll and
communicating with not only the peripheral ports but with the lateral ports at
opposite sides of said dam, substantially as described.

page_text: 2. An imperforate metal roll having a central passage b, a series of longitudinal
ports close to its imperforate periphery, and intermediate lateral ports between said
central passage and said peripheral ports, and a dam in the said central passage
whereby water introduced through the central passage at one end of the roll is
caused to travel through the lateral ports and the peripheral ports and leave
through the said central passage at the opposite end of the roll to thereby cool the
metal of the roll not only at its centre but also near its periphery, substantially as
described.
3. An imperforate metal roll having a central passage, a series of longitudinal
ports close to its periphery and connected in sets at one end, a series of intermediate
lateral ports at the opposite ends of said peripheral ports and the said central
passage, and a dam adjacent to and beyond the lateral ports wheroby water
introduced at the centre of the roll is made to travel through the said central
passage to the lateral ports and thence out through and into the said peripheral
ports toward the other end of the roll to thus cool the metal of the roll at not only
its centre, but at its periphery, substantially as described.
4. An imperforate metal roll having both an axial inlet and outlet, and peripheral
ports connecting the same and to conduct fluid from the inlet to the outlet, the flow
of fluid through alternate ports being in opposite directions whereby a mean
temperature is obtained, substantially as described.
5. An imperforate metal roll having two series of peripheral ports through which
fluid is circulated, the direction of flow through the ports of one series being
opposite the direction of flow through the ports of the other series, whereby a mean
temperature is obtained, substantially as described.
6. A solid metal roll having an imperforate periphery, an axial inlet, an axial
outlet, a series of ports or channels arranged therein under the periphery, and ports
or channels connecting the longitudinal ports with the inlet and outlet, substantially
as described.
Dated the 6th day of November 1802
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.