AN IMPROVED METHOD AND APPARATUS FOR INDICATING THE HEIGHT OF THE WATER IN STEAM BOILERS
Year: 1872

page_text: LETTERS PATENT to Thomas William Kennard, of 13, Albert
Mansions, Victoria Street, Westminster, Civil Engineer, for the
Invention of "AN IMPROVED METHOD AND APPARATUS FOR INDICATING
THE HEIGHT OF THE WATER IN STEAM BOILERS."
Sealed the 9th May 1878, and dated the 11th November 1872.
PROVISIONAL SPECIFICATION left by the said Thomas William
Kennard at the Office of the Commissioners of Patents, with his
Petition on the 11th November 1872.
I, THOMAS WILLIAM KENNARD, of 13, Albert Mansions, Victoria
-Street, Westminster, Civil Engineer, do hereby declare the nature of the
said Invention for "AN IMPROVED METHOD AND APPARATUS FOR INDICATING
THE HEIGHT OF THE WATER IN STRAM BOILERS," to be as follows:-
My said Invention consists of the application to steam boilers of a
vessel communicating with the boiler and constructed and supported as
herein-after described, which will rise when the water sinks below a
certain level and indicate the fact by the sound of a steam whistle which
it turns on. The said vessel is constructed of metal and closed at the

page_text: top. Communications are formed between the bottom of the vessel and
the lower part of the boiler, and between the top of the vessel and the
upper part of the boiler by means of flexible tubes which permit of
the vessel being raised and lowered. The vessel is supported by a
spring or counterweight which is so regulated that when the vessel is
full of water it will remain in its place, and when empty it will rise.
There is a tube which rises from the top of the vessel terminating in a
steam whistle; this tube passes through a hole in a piece of metal
projecting from the boiler and acts as a guide rod. There is also a guide
rod projecting downwards from the bottom of the vessel which passes
through a hole in another projection from the boiler.
The handle of the steam whistle is attached to a rod which is con-
nected with the upper projection from the boiler, and so arranged that
when the vessel rises the steam whistle will be opened. The projections
from the boiler are so placed that when the vessel is at its lowest point
its top will be level with the height at which the water ought to stand
in the boiler. The vessel being in this position it will fill with water
from the boiler and the strength of the spring or weight of the counter-
weight is so adjusted that when the vessel is full of water it will remain
at its lowest point. The depth of the vessel must be such that when
the water in the boiler has sunk to such a level that it ought to be
indicated, the water in the vessel will flow into the boiler through the
lower flexible tube. The vessel being then empty the spring or counter-
weight will force it up, the steam whistle will be opened and the steam
from the boiler passing through the upper flexible tube into the vessel,
and through the tube on the top of the vessel through the whistle, the
latter will be sounded and the fall of the water in the boiler indicated.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas William Kennard in the Great Seal_
Patent Office on the 10th May 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WILLIAM KENNARD, of 13, Albert Mansions, Victoria Street, West-
minster, Civil Engineer, send greeting.
3
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of November, in the year 3

page_text: of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Thomas William Kennard, Her special
licence that I, the said Thomas William Kennard, my executors, ad-
ministrators, and assigns, or such others as I, the said Thomas William
Kennard, my executors, 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
"AN IMPROVED METHOD AND APPARATUS FOR INDICATING THE HEIGHT OF WATER
IN STEAM BOILERS," upon the condition (amongst others) that I, the said
Thomas William Kennard, my executors or administrators, by an
instrument in writing under my, 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 Thomas William Kennard, do
hereby declare the nature of my 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 several
Drawings therein refered to and hereunto annexed :—
1. The object of my Invention is to indicate when the water.in a
steam boiler has fallen below a certain and safe level, and to draw
attention to the fact by a steam whistle which by means of my Invention
is sounded by the steam from the boiler whenever the water in the boiler.
sinks below the proper and safe level.
2. The apparatus for my Invention consists of a vessel placed outside.
the steam boiler, but-communicating with such boiler, and constructed
and supported and capable of rising or falling, and connected with a
steam whistle, as herein-after described.
3. Such vessel is constructed of metal and closed at the top. A
communication is formed between the bottom of such vessel and the
lower part of the steam boiler by a tube or connecting pipe which may
vibrate up and down at one end, and a like communication is formed ·

page_text: between the top of the vessel and the upper part of the steam boiler by
another like tube or connecting pipe. The vessel is supported by a
spring or counterweight, which is so regulated that when the vessel is
full of water such vessel will remain in its lowest position, but when it
has been emptied of water or the water therein has sunk sufficiently low
such vessel will rise to its highest position.
4. A rigid metal tube rises from the top of the vessel and terminates
in a steam whistle. This tube passes through a hole or bearing in
another piece of metal which projects from and is fastened to the
outside of the steam boiler, and so acts as a guide rod for the vessel. 1
Another guide rod for the vessel projects downwards from the bottom
of the vessel and passes through a hole or bearing in another and lower
piece of metal, which also projects from and is fastened to the outside of
the boiler.
5. The upper and hollow guide rod carries a stop cock, the handle of 1
which is attached to a rod which is connected with the aforesaid upper
projection from the boiler or with the boiler near such upper projection,
and the gear is so arranged that when the vessel rises the handle turns
the stop-cock and so opens communication between the vessel and the
steam boiler on the one side and the steam whistle on the other side.
2
6. The aforesaid projections or bearings from the steam boiler are so
placed that when the steam boiler itself contains a sufficient and safe
quantity of water the vessel is at its lowest position. The vessel being
in this position will by means of the aforesaid lower connecting pipe be
full of water coming from the steam boiler, and the strength of the 2
spring or the weight of the counterweight which supports (and when
necessary raises) the vessel is so adjusted that when the vessel is full of
water the vessel remains at its lowest position.
7. Supposing the vessel to be quite full of water, as the water falls in
the boiler the water in the vessel flows back therefrom into the boiler 3
through the lower connecting pipe, and consequently the quantity of
water in the vessel is gradually reduced. The depth of the vessel must
be such that when the water has so far sunk in the boiler that an alarm
ought to be given (that the boiler requires water) the vessel will have
become empty, or so far emptied that the spring or counterweight will g
raise such vessel, and immediately upon the raising of such vessel a
communication will be opened by the aforesaid stop-cock between the

page_text: vessel and the steam boiler on the one side and the steam whistle on the
other side, and the steam passing through the upper connecting pipe
from the boiler into the upper and hollow guide rod, and so to the vessel
and also to the steam whistle will cause the steam whistle to sound, and
thus give an alarm that the steam boiler requires water.
8. When the steam boiler is sufficiently supplied with water the water
will flow from such boiler through the lower connecting pipe into and
will rise in the vessel, which when sufficiently full of water will over-
balance the spring or counterweight and will fall to its lowest position,
and as it falls the stop-cock in the upper and hollow connecting rod will
be shut, and the steam shut off from the steam whistle.
9. In the annexed Drawings Figure 1 is a front elevation of the
apparatus when fixed at one end of a steam boiler; Figure 2 is a plan
of the apparatus in the same position; Figure 3 is a cross section of the
apparatus.
10. In these Figures "A" is the vessel or indicator placed against
the front face of the boiler; "O" is the upper and hollow guide rod
working through the upper projection or bearing E; B is the lower
guide rod working through the lower projection or bearing D. The
bearings E and D are secured to the face of the boiler, and are so made
as to allow the guide rods to work easily; F is a metal connecting
pipe which keeps up communication between the water space of the
steam boiler and the bottom of the vessel, so as to secure the same level
of water in the vessel and in the steam boiler; G is a like metal con-
necting pipe which keeps up communication between the steam space
of the boiler and the top of the vessel; two flexible joints H and J are
provided at the junction of the connecting pipes F and G with the steam
boiler; two other flexible joints I and K are provided at the junction
of such connecting pipes with the bottom and top of the vessel, so as
to allow the connecting pipes F and G to vibrate-from the points H
and Jas the vessel rises and falls, and yet be steam-tight during the
rise or fall of such vessel; a whistle L is placed on the top of the
hollow guide rod C; such hollow guide rod has a stop-cock M below,
the whistle, and such stop-cock is opened by the rise and closed by the
fall of the vessel, by means of the connection of such stop-cock with
a link and stud P secured to the upper projection, or as I find more.
convenient to the face of the boiler, and such link and stud work the

page_text: stop-cock lever O as the position of the upper and hollow guide rod
changes. At the lower end of the guide rod B a balance lever N is
attached which works from a stud on face of the boiler; to this lever
a weight, which I find more simple than a spring is attached, sufficient
to raise the vessel and its guide rods and apparatus, as such vessel
becomes light from lack of water. The guide bearings D and E are
placed in such situations that when the vessel A. is at its lowest position.
nearest to the guide bearing D, there will be a sufficient and safe
quantity of water in the steam boiler, and when the vessel is in this
position it will be filled with water from the boiler through the con-
necting pipe F, and will be sufficiently heavy to counterbalance the
force of the spring or counterweight; but as the water falls in the
steam boiler the water in the vessel flows back through the connecting
pipe F into the steam boiler, and thereby the water in the vessel sinks,
and when the water in the steam boiler has sunk to such a level as is 1
considered to be unsafe and as ought to be indicated the vessel A
should be so far emptied that the spring or counterweight will force
it up towards the guide bearing E, and as the vessel is so forced up the
stop-cock M. will be opened by means of the lever O and link P attached
to the boiler, and the steam passing through the upper connecting pipe 2
into the upper and hollow guide rod and thence to the vessel, and the
steam whistle L, such steam whistle will be sounded and an alarm will
be given that the boiler requires a supply of water; as the boiler fills
again the water will flow through the lower connecting pipe F into the
vessel, which will then overbalance the spring or weight and will fall, 2
and whilst falling will close the stop-cock and shut off the steam from

page_text: make the best use of space, position, and materials, as circumstances
may require or afford, and I do not claim the exclusive use of any of
the separate parts of the apparatus employed by me, except in com-
bination and for the purpose aforesaid.
In witness whereof, I, the said Thomas William Kennard, have
hereunto set my hand and seal, this Ninth day of May, in
the year of our Lord One thousand eight hundred and seventy-
three
T. W. KENNARD. (L.S.)