IMPROVEMENTS IN THE MANUFACTURE OF PAPER, AND APPARATUS THEREFOR.”
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Arthur Millbourn and Frederick Smith
at the Office of the Commissioners of Patents on the 23rd January 1877.
ARTHUR MILLBOURN, No. 11, Victory Place, New Kent Road, in the County of
Surrey, and FREDERICK SMITH, of No. 160, Battersea Bridge Road, also in the
County of Surrey. "IMPROVEMENTS IN THE MANUFACTURE OF PAPER, AND
APPARATUS THEREFOR.”
"
Our Invention relates to the manufacture of paper in separate sheets by the use
of air pressure in such a manner as to assist the deposit of the pulp fibres on the
frame or mould, and to consolidate the pulp so deposited, and to apparatus for
operating in that manner. For this purpose we mount the mould on a pipe, which
can slide tightly through the bottom of the pulp vat, the said pipe being in commu-
nication with a chamber, in which is maintained by a pump or otherwise a partial
vacuum, and having a stop-cock or valve, by which this communication can be
opened or closed as required. The communication being closed the pipe is slid
downwards along with the mould into the body of the pulp, of which the mould
receives a charge to a depth determined by the depth of the deckle which surrounds
the mould. The pipe and mould are then raised till the mould stands above the
level of the pulp in the vat, whereupon a shake is given to it for the purpose of
spreading the pulp uniformly over it. The pipe is then put in communication with
the vacuum chamber, whereupon the pressure of the atmosphere acting over the
surface of the pulp in the mould forces therefrom a large portion of the water, and
consolidates it on the mould. When it is desired to produce paper smooth on both
sides we apply in addition to the apparatus already described an inverted mould,
which can be pressed down by hydraulic or other pressure on the upper surface of
the pulp deposited, as set forth above. We prefer to connect this inverted mould
with chambers of rarified and compressed air by a pipe provided with stop-cocks or
valves, whereby either of those chambers can be put in communication with the upper
mould. After the latter has been pressed down upon the pulp we close the passage
from the lower mould to the vacuum chamber and open it to the air; we then
open communication from the upper mould to the vacuum chamber and the sheet
of pulp is thereby caused to adhere to the upper mould, which is thereupon raised,
and its pipe being then made to communicate with the reservoir of compressed
air the sheet of pulp is detached from it and deposited on a moveable table
which is introduced below it.

page_text: It is obvious that the vacuum actions mentioned above, instead of being effected
by the excess of the atmospheric pressure over that in a rarified chamber, may be
effected by the use of air condensed to a pressure 'higher than that of the atmo-
sphere. For example, the pulp vat may be covered in air-tight, and the pressure of
air within it may be raised above that of the atmosphere, the pipe from the mould
being in that case open to the air; and in like manner steam or other fluid pressure
might be applied as above described.