IMPROVEMENTS IN REVERSING CALENDERS
Year: 1878

page_text: LETTERS PATENT to Mitchell Graham, of Beltonford Paper Works, Dunbar,
in the County of Haddington, North Britain, Engineer, for the Invention of
"IMPROVEMENTS IN REVERSING CALENDERS."
Sealed the 16th April 1878, and dated the 23rd January 1878.
PROVISIONAL SPECIFICATION left by the said Mitchell Graham at the
Office of the Commissioners of Patents on the 23rd January 1878.
MITCHELL GRAHAM, of Beltonford Paper Works, Dunbar, in the County of Had-
dington, North Britain, Engineer. "IMPROVEMENTS IN REVERSING CALENDERS."
"
of
This Invention relates to improvements in reversing calenders, and has for its
object the reversing of the calender at the proper moment irrespective of the size
of the glazing plates used, the reversal being obtained from the tail end of the
plates themselves, whatever their size, and leaving the rolls running ready to take
in another series of plates. This object is attained by means of plates inserted in
and hinged to the front and back tables of the calender, these plates being controlled
in their movements by the "handfulls paper in their progress backward and
forward through the rolls. Each hinged plate communicates by means of a con-
A wiper
necting rod and lever and pawls with a shaft underneath the tables.
attached to this shaft gives motion to a moveable rod furnished with adjustable
collars, this rod being carried in a metal frame capable of adjustment in a hanger
on the under side of the back table. This metal frame carries two screws, which
screws are made to revolve at a suitable speed by means of a separate belt and
small spur wheels. The metal frame also carries a travelling carriage, to which is
attached the bar whereon is fixed the driving belt guide or shifter. Encased in the
aforesaid travelling carriage is a double half nut, which is made to gear alternately
with the two revolving screws by means of the aforesaid collars on the moveable

page_text: rod coming into contact with a wiper on a spindle on the travelling carriage at each
end of the traverse of the carriage.
The hinged plates inserted in the tables, when acted upon by the "handfull" of
papers or other material to be glazed, rise and fall alternately when acted on by
the tail end of the "handfull," and communicate motion by the aforesaid means
through one or other of the two screws to the double half nut, the nut and
traversing carriage, with the belt guide or shifter attached thereto, travelling the
necessary distance alternately in either direction, and thereby reversing the glazing
rolls at the proper moment.
The apparatus does not require to be readjusted by the attendant, whatever may
be the size of plates used for glazing, and he can stop the calender without inter-
fering with the reversing apparatus.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Mitchell Graham in the Great Seal Patent Office on the 20th July
1878.
MITCHELL GRAHAM, of Beltonford Paper Works, Dunbar, in the County of Had-
dington, North Britain, Engineer. "IMPROVEMENTS IN REVERSING CALENDERS."
My said Invention relates to improvements in reversing calenders, and has for its
object the reversing of the calender at the proper moment irrespective of the size
of the glazing plates used, the reversal being obtained from the tail end of the
plates themselves, whatever their size, and leaving the rolls running ready to take
in another series of plates. This object is attained by means of plates inserted in
and hinged to the front and back tables of the calender, these plates being controlled
in their movements by the "handfulls" of paper in their progress backwards and
forwards through the rolls. Each hinged plate communicates by means of a con-
necting rod and lever and pawls with a shaft underneath the tables. A wiper
attached to this shaft gives motion to a moveable rod furnished with adjustable
collars, this rod being carried in a metal frame capable of adjustment in a hanger
on the under side of the back table. This metal frame carries two screws, which
screws are made to revolve at a suitable speed by means of a separate belt and
small spur wheels. The metal frame also carries a travelling carriage, to which is
attached the bar whereon is fixed the driving belt guide or shifter. Encased in the
aforesaid travelling carriage is a double half nut, which is made to gear alternately
with the two revolving screws by means of the aforesaid collars on the moveable
rod coming into contact with a wiper on a spindle on the travelling carriage at each
end of the traverse of the carriage.
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner in or under which the

page_text: same is or may be used or practically carried into effect, reference being had to the
annexed Sheet of Drawings, and to the letters and figures marked thereon, that is
to Bay,
Figure 1 of the accompanying Sheet of Drawings is a front elevation, and Figure 2
is a side elevation of a calendering machine, with which is combined mechanism
constructed according to my Invention for reversing the rolls. Part of the lower
roll is (in Figure 1) broken away, the more clearly to show the said mechanism.
Figures 3, 4, and 5 are detached views, shewing parts of the reversing mechanism
in front elevation, back elevation, and transverse section respectively.
The
Holes are formed in the front and back tables A, A¹, of the calender, and over
these holes are hinged the flaps or plates a, a', the hinging being on the side nearest
to the rolls in both cases. Vertical rods b, b', exert an upward pressure on the
under sides of these flaps or plates a, a¹, by means of coiled springs, as shewn with
respect to one of the rods in Figure 5, where the said spring is marked r.
rods b, b¹, are secured at their lower extremities to the levers or links c, c¹, con-
nected to the shaft d, which extends transversely across the machine underneath the
lower roll of the pair of rolls B, B'. The collar c³, by which the link c¹ is con-
nected to the shaft d, has a niche or groove cut in its periphery (see Figure 4), in
which niche or groove engages a projection formed on the flat spring p secured to *
the bracket p¹ carried by a rod p. On the shaft d is secured a wiper e (see
Figures 3 and 5), the upper end of which enters a slot formed in the rod f, mounted
so as to be capable of sliding in bearings on a frame h, the said rod f carrying to
adjustable collars g, g¹. The frame h is held so as to be adjustable vertically in a
hanger h¹ secured to the under side of the back table A¹. The said frame h carries
two horizontal screws i, i¹, actuated by the pulley through the pinions k, the said
pulley being driven by a band from any convenient source of motive power.
Fitted to slide horizontally in the frame h, and intermediate between the screws i, i¹,
is the traversing carriage J, in which is encased the block j (Figures 4 and 5), in
the upper and lower sides of which are cut segments of concave screws corresponding
to the threads of the screws i, i¹. On a spindle m passing through the traversing
carriage J is fitted a forked wiper m², depending vertically over and embracing the
rod f, as shewn in Figure 5. From the said spindle m a short wiper o extends, so
as to bear when necessary against the piston x (Figure 3) sliding in the cylinder x¹,
and urged outwards by a spring a, the cylinder ¹ being free to radiate on a pin
at y. The spindle m also carries inside the traversing carriage J a wiper q
engaging in the screw block j', so that when the said spindle is turned (through the
wiper m², as herein-after described), the said wiper q raises or lowers the block j',
to cause it to engage with one or other of the screws i, i'. On the rod n
(Figure 1), which is attached to the traversing carriage J, is secured the belt guido
or shifter N,
The action of the apparatus is as follows:-When a "handfull" of paper is fed
to the rolls the hinged plate a of the front table A is depressed, and the hinged
plate a¹ of the back table A¹ is in its raised position. The plate a is maintained in
the closed position by the flat spring p, the knob on which enters the groove or
niche in the collar c³. When the handfull comes in contact with the back
plate a¹, this latter is depressed, and overcoming the resistance of its spiral spring
releases the flat spring p, and permits the rod b to yield to the upward pressure of
its spiral spring, whereby the front plate a is raised. Motion is imparted from the
rod d through the wiper e to the rod f, and as at the time of the rising of the front
plate a the traversing carriage will be at that end of the frame h (which when
standing in front of the machine in the position from which the view Figure 1 is
taken) is at the left-hand side, the collar g coming into contact with the forked
wiper m¹, the block is through the wiper q brought into gear with the lower
screw, and running along the said screw it causes the carriage J to travel towards
the opposite end of the framing, causing belt shifter N carried by it to move the
belt from one pulley which drives the rolls in one direction to another pulley which

page_text: drives the rolls in the reverse direction; or a reversing clutch may be shifted in
like manner.
The motion of the rollers being now reversed, and the "handfull "
passing through them again, it will depress the plate a, and allow the back hinged
plate a¹ to rise again, the projection on the spring p engaging with the notch in
the collar e, again locks down the front plate, the collar g¹ being thus caused to come
into contact with the wiper m¹; the wiper q raises the block j and causes it to run
upon the screw i¹, whereby the rolls are again reversed, and so on, each passage of the
"handfull" from either side of the machine to the other effecting the reversing of
the rotation of the rolls. The double catch s on the pin m (see Figure 4) engages
with the hook 8' on the said frame h, preventing back-lash when the block j¹ is
thrown out of gear at the end of each traverse. The piston x pressing against the
projection o retains the wipers m¹ and q in the position to which they are brought,
and keeps the block j' engaged with one or other of the screws i, i'.
A certain amount of play is allowed in the movement of the arm c on the
depression of the plate c, so that the said movement is sufficient to lock the said
plate down by engaging the projection of the spring p in the notch of the collar c³,
but is not sufficient to press up the back plate a¹ till the "handfull" of paper passes
from over it, and a like play is allowed in the movement of the lever c¹ on the
depression of the plate a¹, so that the movement of this lever is sufficient to dis-
engage the projection of the spring p from the notch in the collar c², but is not
sufficient to press up the front plate a until the "handfull" has passed from over
it, the raising of the plates a, a', after the "handfull" has passed from over them
-being effected by the springs 7.
Figure 6 is a detail shewing the form of connection of the levers c, c¹, to the
shaft d, the cut-away part being the space through which the levers pass without
imparting motion to the shaft d.
In place of the herein-before described mode of locking down the front plate a
by means of a spring p, the said locking down may be effected by a catch on the
upper part of the rod b¹, which catch on the rising of the said rod will engage over
the edge of the box casting y, Figure 5, to which the flap a' is hinged, whereby
the flap a is prevented from rising. On the depression of the flap a¹ by a "hand-
full" of paper passing over it the catch will be withdrawn, and will pass down with
the rod 61, and the flap a will be free to be urged up by its spring r as soon as the
handfull" has passed from over it.
"
By the use of my Invention the "handfull" of paper (that is, the pile of paper
to be calendered with copper or zinc plates between them) effects the automatic
reversal of the motion of the rolls, irrespective of the size of the sheets being
calendered. When the calendering of a
handfull" is complete the rolls are also
left running, ready to take in another "handfull."
The machine in addition to being provided with mechanism for automatically
reversing the motion of the rolls, may in addition be provided with an ordinary
clutch shifter for stopping the motion of the rolls.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner in or under which the same is or may
be used or practically carried into effect, I would observe in conclusion that I
wish it to be understood that I do not limit myself to the precise details herein-
before described and illustrated, as the same may be varied without departing from
the nature of my Invention; but what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. The improvements in reversing calenders herein-before described, that is to
say, furnishing calenders with mechanism through which the passage of the
"handfulls" of paper in either direction through the rolls automatically effects the
reversal of the direction of the motion of the said rolls, essentially as herein-before
described.
Second. The arrangement and combination of parts constituting the improved

page_text: reversing calender herein-before described and illustrated in the accompanying
Drawings.
In witness whereof, I, the said Mitchell Graham, have hereunto set my hand
and seal, this Eighteenth day of July, in the year of our Lord One thousand
eight hundred and seventy-eight.
MITCHELL GRAHAM. (L.S.)