IMPROVEMENTS IN STEAM GENERATORS to be as follows:-
Year: 1885

page_text: I, JOHN ISAAC THORNYCROFT of Church Wharf, Chiswick in the County of
Middlesex, a member of the firm of John I. Thornycroft & Co, Steam Yacht and
launch builders, do hereby declare the nature of said invention for "IMPROVEMENTS
IN STEAM GENERATORS to be as follows:-
"
This invention has reference to steam generators of the kind wherein the water
is exposed to the action of heat while passing in tubes between two vessels one of
which acts as a steam collector and separator. In a steam generator according to
my invention a horizontal cylindrical steam collector and separator is connected by
two series of tubes with two water vessels or chambers or with two parts of the
same water vessel or chamber, situated at either side of the grate or firebars.
These tubes are arranged in groups, by preference eight in a group, and all the
tubes of one group stand in the same vertical plane or approximately so.
Each tube is connected at its lower end to the water vessel or chamber and at
its higher end to the upper side of the steam collector and separator. The groups
of tubes stand side by side and are so disposed that the double row formed by the
two outer tubes of each group, and likewise the double row formed by the two
inner tubes of each group constitutes a wall or partition, except near the upper and
lower extremities of the tubes. These two walls enclose between them at each side
of the grate a space which acts as a flue for the ascent of the gases from the grate
to the uptake. The first and last group of tubes at each side is of a different con-
figuration from the others so that a partial wall or partition is formed at each end
of the grate to enclose the furnace.
The lower side of the steam separator is protected from the flame by a shield of
non-conducting material, such as asbestos cloth, which connects the walls of tubes
at either side, and constitutes the roof of the furnace.
The furnace is provided with a fire door at one end, and a firebrick deflecting
plate at the other. Behind this plate is a short flue passing through the boiler
casing for the escape of steam in case a tube should burst.

page_text: The firebars or some of them are or may be tubes through which water circulates.
These tubes may be continuations or parts of the tubes mentioned above, or they
may be independent tubes connected with the water vessel and the steam
separator.
The steam collector and separator has a steam pipe extending the greater part of
its length. This pipe is protected by one or more baffle plates over which the
mixed water and steam rising through the tubes is poured.
The water falls into the lower parts of the separator and descends through one or
more large return tubes to the water chamber or vessel. The steam turns under
the baffle plate and enters the steam pipe. I provide the collector with two safety
valves, of which one is constructed in combination with a stop valve or regulator,
Deted this 21st day of January 1885

page_text: I, JOHN ISAAC THORNYCROFT, of Church Wharf, Chiswick in the County of
Middlesex, a member of the firm of John I. Thornycroft & Co, Steam Yacht and
Launch builders, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This invention has reference to steam generators of the kind wherein the water
is exposed to the action of heat while passing in tubes between two vessels one of
which acts as a steam collector and separator.
In a steam generator according to my invention a horizontal cylindrical steam
collector and separator is connected by two series of tubes with two water vessels
or chambers or with two parts of the same water vessel or chamber, situated at
either side of the grate or firebars. These tubes are arranged in groups, by
preference eight in a group, and all the tubes of one group stand in the same
vertical plane or approximately so.
Each tube is connected at its lower end to the water vessel or chamber and at its
higher end to the upper side of the steam collector and separator. The groups of
tubes stand side by side and are so disposed that the double row formed by the
two outer tubes of each group, and likewise the double row formed by the two
inner tubes of each group. constitutes a wall or partition, except near the upper
and lower extremities of the tubes. These two walls enclose between them at
each side of the grate a space which acts as a flue for the ascent of the gases from
the grate to the uptake. The first and last group of tubes at each side is of a
different configuration from the others so that a partial wall or partition is formed
at each end of the grate to enclose the furnace.
The lower side of the steam separator is protected from the flame by a shield of
non-conducting material, such as asbestos cloth, which connects the walls of tubes
at either side, and constitutes the roof of the furnace.
The furnace is provided with a fire door at one end, and a firebrick deflecting
plate at the other. Behind this plate is a short flue passing through the boiler
casing for the escape of steam in case a tube should burst.
The fire bars or some of them are or may be tubes through which water
circulates. These tubes may be continuations or parts of the tubes mentioned
above, or they may be independent tubes connected with the water vessels and the
steam separator.
The steam collector and separator has a steam pipe extending the greater part
of its length. This pipe is protected by one or more baffle plates over which the
mixed water and steam rising through the tubes is poured. The water falls into
the lower parts of the separator and descends through one or more large return

page_text: tubes to the water chamber or vessel. The steam turns under the baffle plate and
enters the steam pipe. I provide the collector with two safety valves, of which
one is constructed in combination with a stop valve or regulator.
Referring to the accompanying two sheets of illustrative drawings Fig. 1 is a
front elevation and Fig. 2 a longitudinal section of a steam generator according to
my invention shown as mounted in a boat or vessel represented in section.
Fig. 3
is an elevation of the steam generator with the front plate removed, showing more
particularly the arrangement of the tubes in the first row. Fig. 4 is a transverse
section in the line A. B Fig. 2. Figs. 5, 6, & 7 are detail views drawn to an
enlarged scale, of a portion of a baffle plate hereinafter described. Figs. 8
and are developed surfaces of the upper portions of a steam collector and
separator and a water vessel or chamber respectively. 1. is a horizontal cylindrical
steam collector and separator; 2 and 2 are water vessels or chambers situate one
at each side of the fire grate 3, and 4, 4 are two series of tubes connecting the
steam collector and separator 1 with the water vessels or chambers 2, the whole
forming a steam generator. The tubes of each series are arranged in groups of
eight tubes each, A. B. C. D. E. F. G. H as shown in Figs. 3 and 4, their lower ends
being secured to the upper part of the water vessels or chambers 2 and their other
ends to the upper part of the steam collector and separator 1. The two inner
rows of tubes G. H. and the two outer rows of tubes A. B, of each series, excepting
those of the first and last groups are so disposed and arranged by bending that
they constitute inner and outer walls or partitions except near the upper and lower
extremities of the tubes where openings 5 and 6 respectively are left as shown in
Fig. 4 for the entrance and exit of products of combustion. Within the flue or
space thus formed at cach side of the fire grate by the tubular walls or partitions,
the remainder of the tubes, excepting the first and last groups, are situated as
shown. The tubes constituting the first and last groups A. B. C. D. E. F. G. H of
each series, are so bent and arranged, as shown in Figs. 3 and 4 that they form a
partial wall or partition 7 at each end of the fire grate 3 to enclose the furnace.
8 is a shield of non-conducting material such as asbestos cloth for preventing the
direct impact of the furnace flame upon the lower side of the steam separator
and collector. This shield extends the whole length of the furnace so as to form
the roof thereof and connects the inner walls of tubes as shown. 9 is a balanced
fire-door at one end of the furnace and 10 is a deflecting plate or block of refractory
material such as fire brick at the other end. 11 is a flue passing through the
generator casing 12; it serves for the escape of steam in the event of a tube
bursting. 13 is the ash pan and 14, 14 are the fire bars of the furnace. These
fire bars which are shown of ordinary solid form may be formed of tubes through
which water may circulate as hereinbefore mentioned. 15 is a baffle plate, of
curved form in transverse section, secured within the steam separator and
collector 1. 16 is a perforated steam pipe arranged beneath the battle plate. Over
the baffle plate jets of mixed water and steam are poured from the upper ends of
the tubes when the steam generator is at work, the water falling to the lower
part of the separator and collector 1 whilst the steam turns under the baffle plate
and enters the steam pipe 16. To enable the steam to readily separate from the
water the lower ends or edges of the baffle plate are preferably notched and cut as
shown more clearly in Fig. 5, the edges or portions 17 and 18 being afterwards so
bent as to project at right angles to the remainder of the plate as shown in side
and transverse sectional views in Figs. 6 and 7. By this construction, water
projected against the baffle plate will run off at its lower edges 19 only, whilst
steam similarly projected, will readily pass through the notched openings 20. 21 is
a return tube in communication at its upper end with the separator and collector 1
and provided with two branches 22, indicated in dotted lines in Fig. 4, that are in
communication with the water vessels or chambers 2 as shown. Through these
tubes the water separated from steam in the separator 1 passes to the water
vessels or chambers 2 from which it is again caused to rise through the series of

page_text: tubes by the heat of the furnace. 23 is a combined safety valve and stop valve
or regulator. A second safety valve not shown is fitted to the outlet branch 24
at the opposite end of the separator or collector. Flame and heated products of
combustion from the furnace pass through the openings 5 to the flue or space
between the inner and outer tubular walls or partitions and impart heat to the
tubes in their course. The products of combustion finally escape through the
openings 6 to the flue 25 which is in communication with an uptake or chimney 26.
27 is the boat or vessel in which the steam generator is shown mounted.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The combination in a steam generator of the water chambers. 2, steam
collector and separator 1, and connecting pipes or tubes 4 arranged and operating
as described and shewn.
2. Apparatus for generating steam substantially as described with reference to
and shewn in the drawings.