IMPROVEMENTS IN MACHINERY FOR SMOOTHING OR FINISHING PAPER
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by James Roger Crompton at the Office
of the Commissioners of Patents, with his Petition, on the 2nd
January 1865.
I, JAMES ROGER CROMPTON, of Elton, in the County of Lancaster, Paper
Maker, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN MACHINERY FOR SMOOTHING OR FINISHING PAPER," to be as follows:-
Paper requiring to be finished by having its surface smoothed is passed
between rollers for that purpose known as calenders, and these rollers are
arranged in sets placed one above another in any convenient number.
The paper after leaving the drying cylinder may and generally does pass
between the two upper rollers of one calender and over the surface of and
between the other rollers of the same set, and when a second calender is used,
the paper passes from the lower part of the first calender to the upper part of
the second calender, and between the rollers of the said second calender to be
more highly finished.
The paper in passing from one calender to another often breaks and causes
considerable waste when the calenders are coupled together by gearing as in
common use.

page_text: One of my improvements has for its object the prevention of the breakage
of the paper, and consists in driving the second set of rollers or second
calender by a separate steam engine, turbine, or water wheel, by which means
the paper passing from one calender to the other may be kept at any desired
tension by the power allowed to be exerted by the steam engine, turbine, or
water wheel, and if the motive power be less than that required to
turn the calender and overcome the tensile strength of the paper, breakage
will be avoided.
If more than two calenders be used, I apply a steam engine, turbine, or
water wheel to each additional calender.
My next improvement has for its object the prevention of creased or fulded
paper when passing through the calender rollers damaging the smooth
surfaces of the said rollers.
When the end of the paper is passed between the calender rollers it is apt
to double over or crease, and the lower rollers having considerable pressure
upon them, the creased or doubled paper indents the rollers and impairs their
surfaces. To prevent this I place separate levers to act on each end of all
the rollers in the calender except the bottom one in such a manner as to lift
them a sufficient distance to allow the creased paper, if any, a free passage
between the said rollers without damaging them, and when the paper is
passing evenly between all the rollers they are again lowered and the process
of smoothing or calendering goes on without damaging the rollers by the
action of creased paper.
If there are five rollers in the calender the paper will make four passages
between the rollers, and if these rollers be required to be separated from each
other one-twentieth of an inch, the second roller from the bottom will require
to be lifted that amount, and the third roller from the bottom will require to
be lifted double that amount, and the fourth three times that of the first, and
the fifth four times that of the first, and so on for any greater number of rollers.
I accomplish this variable lifting by acting on the before-named levers with
variable movable inclined planes, which move either in straight lines or
curves, or by screws of varying pitch, or by screws of the, same pitch varying
in the number of revolutions for each separate lift, I also accomplish the same
purpose of variable lifting by levers having their fulcrae fixed in the cheeks
of the calender or attached thereto. The said levers vary in the lengths
between their respective fulcrae and the weights, or between their respective
fulcrae and the powers. I also accomplish the said lifting by variable inclined
planes passing under the ends of each roller, the said planes being acted upon
by other inclined planes or screws as may be required. The inclined planes

page_text: under the end of each roller may be of the same inclination and acted upon
by variable inclined planes or variable screws or screws of the same pitch
varying in the number of their revolutions.
Whether levers, screws, or inclined planes are used, they are coupled
together so as to lift the rollers parallel to each other, or nearly so by the
action of rods, shafts, wheels, worms, screws, or levers, as may be most con-
venient.