to the Boiler on the Breakage of its Glass.
Year: 1887

page_text: Date of Application, 30th Dec., 1887
Specification Accepted, 3rd Feb., 1888
to the Boiler on the Breakage of its Glass.
I, FRANK ARTHUR DRUMMOND of the City of Winnipeg, in the County of Selkirk,
Province of Manitoba and Dominion of Canada, clerk 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 ordinary water gauge which visibly shews the height of the water in steam:
boilers at or about its proper level, consists of a vertically-placed glass tube, which is
seated and securely packed into metal channels connecting it with the boiler, one at
the top and the other at the bottom the glass, the whole forming a runway on the
exterior of the boiler, so that the water appears standing in the glass at the same level
as in the interior of the boiler. This glass is liable to breakage, either by accident
from the outside, or by overpressure from the inside, and various expedients have been
adopted, first, to form metal guards around the glass, and secondly, to check the
rush of steam and water should the glass he broken, so as to prevent any accident to
the attendant who, under ordinary circumstances would have to screw in the check.
valves at the top and the bottom of the broken glass.
The object of this invention is not directed to the protection of the glass so much as
to the effectual and automatic closing of the ports to the boiler similtaneously with the
breaking of the glass, thus instantly preventing the escape of scalding water and
steam. At the same time the arrangement which is shewn in this invention will
permit the engineer or attendant to blow off and clear the glass just as he would do
in any ordinary glass water gauge.
I attain the foregoing objects by the mechanism illustrated in the accompanying
drawings, in which
Figure 1 is a vertical section of the upper portion of the water gauge as it appears
attached to the boiler. Figure 2 is a vertical section of the lower portion of the water
gauge, forms a continuation of Figure 1 and is sectioned in the same line and plane
as that figure. Figures 3 and 4 are sections across the glass tube showing the
internal glass supports which form the primary arrangement in this invention.

page_text: Similar letters of reference indicate similar parts throughout the several views.
A is the steam boiler.
Dis the upper brass of the gauge screwed into the boiler at P, and C is the lower
brass of the gauge screwed into the boiler at Q.
B is the glass indicator tube which is seated into the upper brass by means of the
screw packing nut M, and into the lower brass by means of the screw packing
nut M. The nut M¹ is not directly attached to the upper brass, but to an inter-
mediate screwed sleeve O, for the purpose of facilitating the removal of the glass
indicator tube or its insertion into the brasses.
E2 is the lower glass ball valve, which rests, off its seat, on the pin J, and is sur-
mounted by another glass ball F. Resting on these balls E2 and are a number of
short supporting glasses G G G, which are confined within the glass indicator-tube B
and are continued throughout its entire length. These supporting glasses are sur-
mounted by a longer glass piece G₁, and this, in turn, is surmounted by the upper
glass ball valve E¹. There must be a sufficient quantity of these supporting glasses
inserted or dropped into the glass indicator tube, to support the glass ball valve Ein
an unseated position, as shewn in Figure 1. It is necessary that these supporting
glasses G G G must not only be in short lengths, but must also be of such a shape,
that there will be a ready passage for the water between them and the sides of the
glass indicator-tube B, a preferable form is shewn in figure 3, and glass balls, as
appear in figure 4, may be used so long as they are of smaller diameter than the tube,
and in sufficient number to keep the glass ball valves out of their seats. Now, the
object of this arrangement of glass ball valves, as the first part of my invention, is
simply explained. That if the glass indicator tube breaks, either from an exterior
blow or interior overpressure, the instant it goes to pieces, the intervening supporting
glasses, of course, fall out, and the pressure of the steam in the boiler drives the glass
ball valves E' and E into their seats, and thus instantly and effectually prevents any
outflow from the boiler.
As to the second part of my invention it is necessary to state, that in other gauges
there have been glass ball valves used so as to close the ports to the boiler automati-
cally; but it has been found impossible for the engineer to blow-off or clear the
indicator glass, as the balls, which were placed in the horizontal chambers of the
brasses, immediately closed the ports if the pressure were removed by a blow-off cock
being opened beyond them and the boiler.
In this gauge the valves being kept open by the intervening supports G. G. G. are
in no way affected by the rush of steam or water through tho blow-off cock U. which
is shewn shut-off wise in the drawings. In fact in any gauge using valves the
particles of scale or dirt which usually permeate boiler water are very apt to clog and
render the action of the valves useless and the indicator tube dull and opaque, unless
the glass can be blown off. In this gauge the interior may be cleaned of any dirt
accumulations, by screwing in the lower check valve H2, against its seat, when the
steam may be blown off through the upper channel, W, clear through the entire gauge,
making its exit at S.
Both the upper and lower brasses are so designed and constructed as to be best
suited for this peculiar combination of devices. The glass indicator tube can be readily
taken out and put in place by unscrewing the upper end of the interior sleeve, O, the
glass filling the vacancy in the sleeve as the sleeve descends over the glass. The
lower packing nut M² may then be released and the glass lifted out. Before removing
the glass indicator tube and the portions of the brass connecting it, the upper glass
ball-valve E, must be freed by screwing out the pin J, which is held in place by a
jam-nut X. Then the upper supporting piece G¹ and the glass ball-valve El may be
shoved up so as to allow the glass indicator-tube B to be removed. This operation
will require the removal of the screw cap Y, when the whole chamber L will be
exposed. The whole may be replaced in the same way. The last supporting piece G'
being dropped through the top of the chamber L and then surmounted by the upper
glass ball valve, E', after which the cap Y may be screwed on and the pin J screwed
down so as to hold the upper glass-ball valve loosely in position.

page_text: The upper supporting piece G', it will be noticed is made longer than the pieces
underneath it, as short pieces might engage with the upper end of the glass indicator
tube, and thus prevent the glass ball valve E' from falling into its seat.
In this gauge the distance of the brasses apart can be fixed to any length of glass
required.
It will be noticed that the channel from the boiler to the upper part of the gauge,
enters at W, in the side of the chamber L, and that the upper check valve H', is placed
in this channel so that there is, by this means a full opening into the chamber.
Throughout this specification the names occur as follows, "supporting glasses,"
"glass balls,"" glass ball valves," and it may be here stated that they are not thus
termed from their relation to the glass indicator tube, but that the material of which
they are constructed is glass, this material being preferably used, not only from its
non-liability to surface adhesion, of dirt, but from its transparency in affording a clear
view of the water level.
In the drawings the upper check valve H' being in rear of the main sectioning of
the drawings, is not sectioned; but is of the same construction and section as the
lower check valve H2.
In figure 4 the supporting glass balls are shewn randomwise as they might appear
when looking down the section of the indicator tube.
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-In a water gauge for steam boilers for automatically closing its ports to the
boiler on the breakage of the glass, an under glass ball valve off its seat supported in
the vertical channel of the gauge and below the glass indicator tube, a series of glass
supports resting upon the under glass ball valve and passing pillarwise through the
glass indicator tube, and an upper glass ball valve in the vertical channel of the gauge
above the glass indicator tube supported, off its seat, on the top of this series of glass
supports, substantially as described and for the purposes set forth.
2-In a water gauge for steam boilers for automatically closing its ports to the
boiler on the breakage of the glass, a blow-off cock U, a lower check-valve H², an
under glass ball-valve, off its seat, supported in the vertical channel of the gauge and
below the glass indicator tube, a series of glass supports resting on the under glass
ball valve and passing pillarwise through the glass indicator tube, an upper glass ball
valve in the vertical channel of the gauge above the glass indicator tube, supported,
off its seat, on the top of this series of glass supports, and an upper check valve H¹
substantially as described and for the purposes set forth.
Dated this First day of November 1887.
FRANK ARTHUR DRUMMOND.