IMPROVEMENTS IN VACUUM BOXES FOR PAPER-MAKING MACHINES
Year: 1878

page_text: LETTERS PATENT to Sam Mason, junior, of Manchester, in the County of
Lancaster, Engineer, John Wolstenholme, of the Albert Works, Radcliffe
Bridge, in the same County, Hydraulic Engineer, and Samuel Spencer, of
Radcliffe Bridge aforesaid, Engineer, for the Invention of "IMPROVEMENTS
IN VACUUM BOXES FOR PAPER-MAKING MACHINES."
PROVISIONAL SPECIFICATION left by the said Sam Mason, John Wolsten-
holme, and Samuel Spencer at the Office of the Commissioners of Patents on
the Sth April 1878.
SAM MASON, junior, of Manchester, in the County of Lancaster, Engineer,
JOHN WOLSTENHOLME, of the Albert Works, Radcliffe Bridge, in the same County,
Hydraulic Engineer, and SAMUEL SPENCER, of Radcliffe Bridge aforesaid, Engineer.
"IMPROVEMENTS IN VACUUM BOXES FOR PAPER-MAKING MACHINES."
The object of our Invention is to prevent injury by friction to the endless wire
gauze, on which the pulp is carried over the vacuum box. We inake a channel on
cach side of the vacuum box, which is made of brass or other suitable metal. In
each channel is a roller covered with india rubber or other suitable elastic material;
the bearings of these rollers are acted upon by springs which press the roller against
the inner edge of the channel, which acts as a doctor to keep the surface of the
roller clean and to exclude air. Near each end of the vacuum box is an endless
band, of india-rubber or other elastic material, which fits in a groove in the regu-
lating clows, and these endless bands pass over the side rollers above referred to.
Loose washers are placed at each end of the side rollers, the position of which is
varied according to the width of paper that is being made. By this means as the
endless wire gauze is carried over the vacuum box the partial vacuum presses the
wire gauze on to the rollers and side bands, all of which are carried round by the
wire gauze, and the friction hitherto unavoidable is entirely dispensed with.

page_text: The side rollers may be turned round by bands from the scutch roller, or from
any other convenient part of the machine.
Our Invention may be applied to the ordinary wood vacuum boxes now in use.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Sam Mason, John Wolstenholme, and Samuel Spencer in the Great
Seal Patent Office on the 5th October 1878.
SAM MASON, junior, of Manchester, in the County of Lancaster, Engineer,
JOHN WOLSTENHOLME, of the Albert Works, Radcliffe Bridge, in the same County,
Hydraulic Engineer, and SAMUEL SPENCER, of Radcliffe Bridge aforesaid, Engineer.
"IMPROVEMENTS IN VACUUM BOXES FOR PAPER-MAKING MACHINES."
The object of our Invention is to provent injury by friction to the endless wire
gauze on which the pulp is carried over the vacuum box. We make a channel on
each side of the vacuum box, which is made of brass or other suitable metal or
material. In each channel is a roller covered with india-rubber or other suitable
elastic material; the bearings of these rollers are acted upon by springs which press
the roller against the inner edge of the channel, which acts as a doctor to keep the
surface of the roller clean and to exclude air. Near cach end of the vacuum box
is au endless band, of india-rubber or other clastic material, which fits in a groove
in the regulating clows, and these endless bands pass over the side rollers above
referred to. Loose washers are placed at each end of the side rollers, the position
of which is varied according to the width of paper that is being made. By this
means as the endless wire gauze is curried over the vacuum box the partial vacuum
presses the wire gauze on to the rollers and side bands, all of which are carried
round by the wire gauze, and the friction hitherto unavoidable is entirely dispensed
with.
The side rollers may be turned round by bands from the scutch roller, or from
any other convenient part of the machine.
Our Invention may be applied to the ordinary wood vacuum boxes now in use.
And in order that our Invention may be fully understood we will proceed to
describe the accompanying Sheet of Drawings.
Fig. 1 is a side elevation; Fig. 2, a plan; and Fig. 3, a transverse section of a
vacuum box for a paper-making machine constructed according to our Invention.
a is the outer case of the box, and 6 the inner case, both of which are made by
preference of sheet brass or copper, but they may be made of other metal or
material. The spaces between the outside of the case b and the inside of the case a
form channels, in which are placed the rollers c, c, which are made of sheet brass
or other suitable material, and which may be covered with india-rubber or other
elastic substance if desirable; the bearings of the axles of the rollers c are fixed to
the ends of the case a, and may be provided with springs to press the rollers against
the edges of the inner box b, which act as doctors to keep the surface of the rollers

page_text: clean and to exclude air. Near each end of the side rollers c are loose washers c¹,
made of india-rubber or other suitable material, the position of which can be varied
according to the width of the paper that is being made. At each end of the
vacuum box is an endless band, of india-rubber or other elastic material d, which
fits in a groove in each of the regulating clows e, and these endless bands pass
around the side rollers c, c, and hang down below the trough, as shewn in Fig. 3.
In wide machines the deflection of the side rollers c is prevented by one or more
pairs of antifriction rollers f, which are also pressed upwards by springs, as shewn
in Fig. 3; these rollers ƒ may be made to extend the whole length of the vacuum
box.
The side rollers c, c, may be turned round by a strap from the scutch roller or
other convenient part of the paper machine, passing around the pulley c³ and by a
band passing around the pulleys c², c².
The clows e, e, are moved to and fro to regulate the position of the bands d, d,
according to the width of the paper pulp by the screws d' as usual. By this means,
as the endless wire gauze is carried over the vacuum box, the partial vacuum
formed therein by any of the well-known means or by an ejector, as described in
the Specification of former Letters Patent granted to us on the 20th day of
November, 1876, No. 4485, causes the wire gauze to press upon the rollers c, c,
and side bands d, d, all of which are carried round by the wiro gauze, and consc-
quently the friction of the wire gauze against the edges of the vacuum box, which
was heretofore unavoidable, is entirely dispensed with, thereby increasing its
durability.
Our Invention may be modified, as shown in Fig. 4, in which view the rollers
c, c, are shewn in contact with the inner edge of the vacuum box a, and Fig. 5
represents a section of an ordinary wood vacuum box to which our improvements
are applied; in this case the doctors are fixed to two inner partitions.
It is sometimes desirable to place additional doctors to act on the rollers c, as
shewn in dots in Figs. 3 and 5.
Having thus stated the nature of our Invention, and described the manner of
performing the same, we wish it to be understood that we do not intend to limit
ourselves to the details given; but that what we claim is the application of the
rollers c, acting against the edges of the vacuum box or against thin blades of
metal and the endless bands d, for removing or reducing the friction on the endless
wire gauze.
In witness whereof, I, the said John Wolstenholme, for myself and on behalf
of the within-named Sam Mason, junior, and Samuel Spencer, have here-
unto set my hand and seal, this Third day of October, One thousand eight
hundred and seventy-eight.
JOHN WOLSTENHOLME. (L.S.)