AN IMPROVED FORM OF ENGINE FOR PREPARING PULP FOR PAPER MAKING."
Year: 1880

page_text: LETTERS PATENT to William Umpherston, of Bowershall Engine Works, Leith,
for an Invention of "AN IMPROVED FORM OF ENGINE FOR PREPARING PULP
FOR PAPER MAKING."
PROVISIONAL SPECIFICATION left by the said William Umpherston at the
Office of the Commissioners of Patents on the 17th March 1880..
WILLIAM UMPHERSTON, of Bowershall Engine Works, Leith.
FORM OF ENGINE FOR PREPARING PULP FOR PAPER MAKING."
"AN IMPROVED
In the common and almost universal form of engines used for preparing the pulp
for paper making the pulp travels or revolves horizontally in a tub or trough with
semi-circular ends and straight sides, partly divided longitudinally by a partition
called the midfeather, around which the pulp flows from the back of the roll to its
front, where it passes under the roll and over the bottom working plate, and is
again delivered over the the back fall to pass again round the midfeather to the front
of the roll. In the course of these repeated revolutions part of the pulp near the
circumference of the tub has much further to travel than the part near the
midfeather, and consequently is not so often operated upon, and the pulp is thus
unequally treated.
As an improvement upon this form of tub I make it so that the pulp passes from
the back of the roll to its front through a longitudinal passage under the back fall,
the pulp thus moving as through an inverted syphon, the superincumbent weight of
the semi-fluid pulp as delivered over the back fall at the back of the roll pressing
it along this passage and upwards to enter again in front of the roll, and I claim as
my Invention any form of a tub so constructed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Umpherston in the Great Seal Patent Office on the 17th
September 1880.
WILLIAM UMPHERSTON, of Bowershall Engine Works, Leith.
FORM OF ENGINE FOR PREPARING PULP FOR PAPER MAKING."
"AN IMPROVED
In the common and almost universal form of engines used for preparing the pulp
for paper making the pulp travels or revolves horizontally in a tub or trough with
semicircular ends and straight sides, partly divided longitudinally by a partition
called the midfeather, around which the pulp flows from the back of the roll to its
front, where it passes under the roll and over the bottom working plate, and is
again delivered over the back fall to pass again round the midfeather to the front
of the roll. In the course of these repeated revolutions part of the pulp near the
circumference of the tub has much further to travel than the part near the
midfeather, and consequently is not so often operated upon, and the pulp is thus
unequally treated.
As an improvement upon this form of tub I make it so that the pulp passes from
the back of the roll to its front through a longitudinal passage under the backfall,
the pulp thus moving as through an inverted siphon, the superincumbent weight,
of the semi fluid pulp as delivered over the back fall at the back of the roll pressing
it along this passage and upwards to enter again in front of the roll.
The Invention will be clearly understood on reference to the accompanying
Drawing, which shows a longitudinal section of the improved form of engine. The
roll A, bottom plate B, and the form of the back fall C is similar to those of
ordinary engines, but the trough is formed with the passage D under the bottom
plate B, so that the semi fluid contents of the engine in travelling from the back
fall C to the front of the roll A pass by means of the passage D under the bottom
plate B in the direction indicated by the arrows, the superincumbent weight of the
semi fluid pulp as it is delivered over the back fall C at the back of the roll A
pressing it along the underpassage D and upwards to the front of the roll A. The
position of a drum washer is shown at E, and at F is seen a section of the cross
shaft for raising or lowering both ends of the roll A simultaneously; G is the roll
cover, which may be of any usual form.
By this Invention the semi fluid pulp is acted upon in a more effective manner,
and its particles are also more equally treated than has hitherto been the case.
And having now described the nature of my said Invention and in what manner
the same
to performed, I declare that I claim, the improved form of engine for
preparing pulp for paper making, as described, and substantially as shown in the
accompanying Drawing.
In witness whereof, I, the said William Umpherston, have hereunto set my
hand and seal, this Fifteenth day of September, One thousand eight hundred