Improvements in Liquid Gauges.
Year: 1891

page_text: Date of Application, 15th Apr., 1891-Accepted, 22nd Aug., 1891
Improvements in Liquid Gauges.
We PAULINE MARIE PINEL Vve LETHUILLIER and CHARLES LOUIS PIXEL
both of 26 Rue Meridienne Rouen (Seine Inférieure) in the Republic of France,
Engineers, 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 :-
The object of this invention is to provide liquid gauges which obviate danger of
bursting and the dangerous consequences thereof.
In an efficient liquid gauge it is necessary.
1. That the level of the water inside the tube be capable of being read off
with case both from the front and from the sides at as great a distance as
possible.
2. The tube should be as free from liability to breakage as possible and in any
case it should not if broken cause further damage, and it should be capable of
being easily and quickly replaced even whilst the boiler or other apparatus with
which it is used is at work.
3. The tube should be capable of being frequently cleaned without liability to
breakage and provision should be made to render breakage incapable of doing
mischief in case it should occur.
4. The tube should be so arranged as to be incapable of being put in place in
an inclined position in which it is unequally supported and rendered liable to be
broken.
The first of these conditions may be fulfilled by employing self-luminous tubes
or by employing small floats for rendering the level of the water plainly visible.
The three other conditions are provided for by the novel arrangements hereinafter
described.
In the accompanying drawings.
Figure 1. represents in side elevation partly in section Figure 2 in front view
and Figure 3 in horizontal section a gauge constructed according to this invention
the cocks communicating with the boiler not being shown.
Figure 4. shows detached the index designed for shewing the normal level of
the liquid and combined with a lamp holder or support.
Figures 5, 6 and 7, are detail-views of the junction or packing plate and the two
washers of india rubber or other easily compressible substances serving to prevent
leakage from the two concentric indicating tubes.
Figures 8, 9 and 10 represent in elevation section and plan an apparatus similar
to the preceding, but provided with two cocks communicating with the boiler.
These cocks are provided with conical valves worked by a small hand wheel at the
end of a screw-rod.
In Figures 11 and 12 the apparatus is furnished with plug cocks the sockets
being closed at one end to prevent leakage.
This type has no flanges but has two screwed ends which enable connection to be
made with the boiler by means of tubes of suitable lengths.
Figure 13. shews another example in which the cocks are replaced by conical
valves.
It should be first of all pointed out that in this system the protection of the
glass tube T against currents of air or blows is effected by a second glass tube P,
in which it is enclosed, an arrangement which has been iried but without success
owing to the want of a practical means of putting together or fitting
We have devised the following means of rendering the fitting of both
the inside

page_text: and outside tubes at once accurate, simple, and expeditious, which is the main
feature of our new system.
For this purpose the two tubes are connected at their ends by two rings or
washers and b and by a packing plate R, of a special shape and made of india-
rubber or any other material capable of producing a tight joint. The washers
and the plate are arrange in such a way that the tubes may be used simultaneously
or separately according as required,
The two tubes furnished above and below with their rings or washers are con-
nected with the boiler by connections A and A' which together with the metallic
tube D make up the tube-support. These two connections are provided with semi-
circular recesses for the reception of the said rings (see plan Figure 2) and are
cast with ears to receive the caps C and C of corresponding shape, the packing
plate R being inserted between (for details see Figure 5) and the whole is tightened
together by means of screws in the same way as the cap of a plummer block is
screwed down on the brasses of a shaft.
On fitting, the washers and the plates are separate, but after the apparatus has
been in use in consequence of the high temperature to which the apparatus is
exposed, the plates and the washers run together so that the three parts of each
connecting tube form one piece establishing a perfect joint which is rendered even
more secure by the pressure of the cap.
It will be observed that the caps C and C of the connecting tubes A and A' are
provided with small boxes B and 13 enclosing spherical valves S.
Under ordinary circumstances, that is to say with two tubes, a current of air is
set up through the apertures not closed by the valves, which prevents condensation
of vapour between the two tubes but should the inside tube burst these valves
close automatically under the pressure of the steam and water contained in the
protecting tube so that no escape can take place.
We have still to draw attention to an improvement in construction of con-
siderable importance it consists in replacing the plate which under ordinary
circumstances connects the two tubes A and A' by a metallic tube support D
arranged so as to receive the extremity of the clearing cock D'.
This tube, preferably polygonal in shape to enable it to be turned with greater
ease by hand is tapped with a screw-thread at the ends-a right handed screw at
one end, and a left-handed one at the other, to enable the connecting tubes to be
approached or drawn together simultaneously and consequently to ensure with
-perfect accuracy the proper distance between their axes-the connecting tubes
themselves being correspondingly tapped.
This tube consequently unites in this manner the two tube carriers as if they
were cast in a single piece the result being to ensure the proper fitting of the glass
tubes when the apparatus is correctly put together.
The index or pointer E is attached to the tube D at the desired level (seen in
detail Figure 4) and may be fitted as indicated above with an arm for receiving a
small gas or oil lamp which will enable the level of the water to be read off at
night.
The general arrangement of our novel apparatus has for a result.
1. That under ordinary circumstances the water finds its level only in the inside
tube T but is visible through the two tubes.
2. That if the outside tube is broken by a blow or other cause the level is still
shown in the inside tube which then acts as an ordinary water gauge.
3. If the inside tube burst the level is still indicated in the out-ide tube which
in it turn becomes an ordinary water gauge.
The effect of this is that the two concentric tubes are capable of acting
simultaneously or successively-simultaneou-ly when both are intact successively
when one is fractured.
By means of this arrangement any escape is rendered impossible. The outside
tube not being subjected to any internal pressure there is nothing to propel its
fragments outwards if it breaks and the internal tube cannot have its fragments

page_text: thrown outwards as it is protected by the external tube. In any case the frag-
ments would remain inside the protecting tube as the distance between them is too
small for the particles to acquire sufficient impetus to break the latter.
Figures 8, 9, 10 and 13 shew the various modifications which we have devised
for the purpose of rendering our invention applicable to a variety of cases, but in
every case the tube-carrier or support D uniting the two small tubes or connecting
tubes A A is retained whether these latter are provided with conical valve
communications F F (Figures 8, 9, 10 and 13) or with closed sockets and "
(Figures 11 and 12) or whether they have in both cases flanges for attaching
direct to the boiler or whether they have unions and for connecting them with
existing fittings.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
First. A multitubular liquid gauge with removeable tube supports enabling the
level of the liquid to be indicated in both or either of the tubes or gauge glasses
substantially as hereinbefore described.
Second. The arrangement of the tube support or carrier with packing plates R
rings or washers and retaining or compressing caps or cover plates C and C
enabling the tubes to be inserted into their supports from the front or horizontally
substantially as hereinbefore described and illustrated in the accompanying
drawings.
Third. The arrangement of the two valve boxes B B having the automatic
valves S serving in case of failure of the internal tube to prevent the escape of
steam and water from the outer tube substantially as hereinbefore described with
reference to the accompanying drawings.
Fourth. The employment of a metallic tube carrier or support D which at the
same time connects the fittings A A' and ensures the correct adjustment of the
gauge glasses substantially as hereinbefore described with reference to the accom-
panying drawings.
Fifth. The arrangements enabling the removeable multitubular gauge tubes to
be constructed with or without flanges and with closed socket cocks such as for
valves such as F F substantially as hereinbefore described and illustrated in
Figures 8 to 13 of the accompanying drawings.
Dated this 15th day of April 1891.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.