IMPROVEMENTS IN VACUUM PANS
Year: 1871

page_text: LETTERS PATENT to John Brough, of New York, United States of
America, but at present of Litchurch, in the County of Derby,
and George Fletcher, the younger, of Derby, in the County of
Derby, Engineer, for the Invention of "IMPROVEMENTS IN VACUUM
PANS."
Scaled the 22nd December 1871, and dated the 7th July 1871.
PROVISIONAL SPECIFICATION left by the said John Brough and
George Fletcher at the Office of the Commissioners of Patents,
with their Petition, on the 7th July 1871.
We, JOHN BROUGH, of New York, United States of America, but
at present of Litchurch, in the County of Derby, and GEORGE FLETCHER,
the younger, of Derby, in the County of Derby, Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN VACUUM
PANS," to be as follows, that is to say :-

page_text: of one-half the circumference of the vacuum pan; and the heating
surface of the tubes is thereby rendered thoroughly effective.
Secondly. In drawing the water from the condenser by one pump
and the air by another:
Thirdly. In employing direct-acting pumps for the air and water
pumps, that is to say, pumps having no crank or fly wheel.
Fourthly. In constructing the injection nozzle so as to discharge a
solid sheet of water across the condenser.
Fifthly. In employing a lense and reflector on the top of the pan
to throw the light into same.
Sixthly. In so arranging the high and low pressure steam valves, that
when the high-pressure valve is opened the low-pressure valve is
self-closing.
Seventhly. In coating the inner surface of vacuum pans made of cast
iron, wrought iron, or any of the baser metals with copper or nickel, tin,
or any suitable metal capable of resisting acids. The metallic coating
is applied to the surface by any of the known electro-metallurgical
processes.
The injection nozzle consists of a bell-mouth pipe, having a conical
plug secured in the mouth of same, leaving an annular orifice all round
for discharge of water, of equal area to the pipe, the said nozzle
being placed in the centre of a cylindrical condenser will cause a solid
sheet of water to flow from the centre to the sides all round. The high
and low pressure valves have a common outlet into coils, cach valve
is loose upon its spindle and arranged for the inlet of steam under them,
so that should the high-pressure valve be opened the steam will act
upon the top of the low-pressure valve, which being loose on its spindle
will close.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Brough and George Fletcher in the Great
Seal Patent Office on the 5th January 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
BROUGH, of New York, United States of America, but at present of
Litchurch, in the County of Derby, and GEORGE FLETCHER, the younger,
of Derby, in the County of Derby, Engineer, send greeting.
3

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of July, in the year of
our Lord One thousand eight hundred and seventy-one, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said John Brough and George Fletcher, Her
special licence that we, the said John Brough and George Fletcher, our
executors, administrators, and assigns, or such others as we, the said
John Brough and George Fletcher, our exccutors, administrators, and
assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN VACUUM PANS," upon
the condition (amongst others) that we, the said John Brough and
George Fletcher, our exccutors or administrators, by an instrument in
writing under our, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said George Fletcher, on behalf of
myself, and the said John Brough, do hereby declare the nature of our
said Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement,
reference being had to the Drawing hereto annexed, and to the Figures
and letters marked thereon, that is to say:—
Our improvements relate to vacuum pans employed for the manu-
facture of sugar and for other purposes, and consist,―
Firstly. In the arrangement of the heating tubes connected with
trunks, by which the steam has only to travel at greatest the distance
of one-half the circumference of the vacuum pan, and the heating
surface of the tube is thereby rendered thoroughly effective.
Secondly. In drawing the water from the condenser by one pump
and the air by another.
Thirdly. In employing direct acting pumps for the air and water
pumps, that is to say, pumps having no crank or fly wheel.

page_text: Fourthly. In constructing the injection nozzle so as to discharge
a solid sheet of water across the condenser.
Fifthly. In employing a lens and reflector on the top of the pan to
throw the light into same.
Sixthly. In so arranging the high and low pressure steam valves,
that when the high-pressure valve is opened the low-pressure valve is
self-closing.
Seventhly. In coating the inner surface of vacuum pans made of cast
iron, wrought iron, or any of the baser metals with copper or nickel, tin,
or any suitable metal capable of resisting acids. The metallic coating
is applied to the surface by any of the known electro-metallurgical
processes.
To make our Invention better understood we will proceed more
particularly to describe the same, and the manner of carrying it into
effect by reference to the accompanying Drawing, in which Figure 1
is a part plan, and Figure 2, an elevation of a vacuum pan constructed
with our improvements.
Firstly. The trunks consist of two hollow tubes or boxes A and B,
one to each worm of heating tubes secured opposite to cach other
to the side of the vacuum pan, and with flanges extending their whole
length on each side, to which the semicircular copper coils are secured.
At the lower end of the trunk B is a branch pipe C, to which a pipe D
of copper or other material is connected, which takes the condensed
water through the bottom or side of the pan; the trunk A, which is
the larger one, is in connection with the steam inlet valve P.
Secondly. The water used as an injection to effect the condensation
of the vapour coming from the vacuum pan is conducted down one of
the columns which support the vacuum pan and its platform, and
on which the condenser sits, or by a separate pipe leading from the
point E, and is drawn or pumped away by a double-action water pump
engine, set apart for that purpose only. The air is drawn off by another
channel or pipe at a point F below the level at which the condensation
of the vapour takes place.
Thirdly. The air pump used for the before-mentioned purpose consists
of a double-action pump in gun metal, cast iron, or other metal, of
a diameter and stroke in proportion to the capacity of the pan, and
connected to the condenser above the point at which the water of

page_text: injection is drawn away. The pump is lubricated by means of a small
cock or valve (in the suction passage) which is in connection with
a water main. In the air pump engine, as in the water pump engine,
there is neither crank, connecting rod, nor fly wheel.
Fourthly. In the construction of the injection nozzle or outlet a
hollow tube G of gun metal or other metal is used, which is slightly
bell-mouthed at top and has a bridge cast in it, into which the spreader
is screwed. This spreader is secured in its position by means of a rod
with a cone on its lower end which passes up through the spreader,
and is adjusted at top by means of a thumb screw H. The lower end
of the spreader is bored to receive the cone on the end of the spindle
which passes through it, and has a saw cut about one-sixteenth of an
inch wide across its diameter, by which means the cone being drawn
by the thumbscrew at the top wedges the bottom of the spreader in
one position in the bridge, and can only allow a limited quantity
of water to pass through at the top J. The top of the injection pipe
being bell-mouthed, and the under side of the spreader being also curved
in proportion directs the water in a solid sheet across the condenser,
thus the vapour is forced to pass through a body of water, by which
it is effectually and instantly condensed.
Fifthly. A glass bull's cyc or lens is seated in the top of the vacuum
pan K immediately over the centre, and is held in its position by means
of a facing or ring of metal L, round which another ring M is made
to slide in a groove, which sliding ring has two pillars secured to it
carrying a concave reflector N, of glass, silver, silvered copper, or other
metal which can be adjusted by means of a cord or chain in the hand
of the pan attendant so as to reflect the light on to the bull's eye or
lens which is seated in the top and thence into the interior of the
vacuum pan.
Sixthly. Each worm or series of copper coils in the interior of the
pan is supplied with steam by means of a combined high-pressure
valve O and low-pressure valve P secured to the side of the pan; the
valves being loose from their spindles are so arranged that should the
handle of the low-pressure valve be left open by inadvertence or from
any other cause, the steam from the high-pressure main when turned
on would close it by its superior pressure.
Seventhly. We coat the inner surface of the vacuum pan made of
cast iron, wrought iron, or any of the baser metals, with copper or nickel,

page_text: tin, or any suitable metal capable of resisting acids. The metallic
coating is applied to the surface by any of the known electro-metal-
lurgical processes.
In witness whereof, I, the said George Fletcher, have hereto set
my hand and seal, this Fourth day of January, in the year of 5
our Lord One thousand eight hundred and seventy-two.
Witness,
W. A. GILBEE,
4, South St.,
Finsbury.
GEORGE FLETCHER, JUN³. (L.S.)