Improvements in Pressure and Vacuum Gauges.
Year: 1893

page_text: Date of Application, 9th Dec., 1893
Complete Specification Left, 10th Sept., 1894-Accepted, 27th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in Pressure and Vacuum Gauges.
We, GEORGE VINCENT FOSBERY, V.C., of 279 Vauxhall Bridge Road,
Lieutenant-Colonel, late H.M. Bengal Staff Corps, and JAMES JOSEPH HICKS,
Meteorological Instrument Maker, of 8 Hatton Garden, both in the County of
Middlesex, do declare the nature of this invention to be as follows ;-
The invention has for its object improvements in gauges for indicating small
amounts of vacuum or pressure, such gauges being specially applicable for
indicating the pressure of gas, the pressure of air in mines, or for showing the
differences of pressure in a ship's stoke hole and in the outer air, the draft into a
furnace or through a flue, and for other purposes.
We employ a metal chamber formed somewhat similarly to that of an aneroid
barometer but not exhausted and which is very sensitive to either pressure or
vacuum, and we provide the same in some cases with a conical nozzle com-
municating with the interior thereof and to which a tube is attached by means of a
corresponding conical fitting, whilst in other cases a tube may be rigidly attached
to such chamber.
The said chamber may be used exclusively for indicating small amounts of
pressure or vacuum, or it may be used for indicating both pressure and vacuum.
In an instrument capable of use for indicating either pressure or vacuum and
suitable for indicating pressure of gas and other light pressures and vacuum, we
enclose a light sensitive chamber in a suitable case; the said chamber, by suitable
gearing, gives motion to a hand or pointer which is caused, by a spring, normally
to rest at the zero point ou the face of the instrument, which latter has a scale on
each side of the zero point and is provided with a stop for the hand or pointer
between the highest points of such scales.
The case of the instrument is provided with a tube communicating with the
interior of the chamber and capable of connection with a pipe, chamber or space,
of which the internal pressure or vacuum is desired to be ascertained.
By this arrangement the hand or pointer is caused to travel in one direction
round the face when indicating pressure, and in the opposite direction when
indicating vacuum.
If it is desired that an instrument should indicate only either pressure or vacuum,
the scale will be divided in one direction only for either of such purposes, and the
hand or pointer will travel only in one direction to indicate the same, being
returned to the zero point by a spring.
Two instruments, consisting of similar chambers with their gearing, hands or
pointers, springs and scales, may be combined in one case and one of them used to
indicate the pressure in a
stoke hole whilst the other is used to indicate the
pressure of the external air; or a single instrument may be used for both purposes,
in which case the chamber and its connected parts will be enclosed in an air-tight
case and the chamber will have a tube connected therewith which will be in
communication with the stoke hole, whilst another tube communicating with
the enclosed space around the pressure chamber will communicate with the
external air.
The face of the instrument has a scale divided in one direction only from the
zero- point. By this arrangement, when communication with the outer air is shut

page_text: off, the pressure in the stoke hole causes the hand or pointer to move forward to the
proper division on the scale to indicate such pressure; then, by opening communi-
cation between the space within the case of the instrument and the outer air, the
latter will cause a certain retrogression of the hand or pointer, by which the
difference of pressures is indicated should any such exist.
Dated this 9th day of December 1893.
GEORGE V. FOSBERY,
JAS. J. HICKS,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Pressure and Vacuum Gauges.
We, GEORGE VINCENT FOSBERY, V.C., of 279 Vauxhall Bridge_Road,
Lieutenant-Colonel, late H.M. Bengal Staff Corps, and JAMES JOSEPH HICKS,
Meteorological Instrument Maker, of 8 Hatton Garden, both in the County of
Middlesex, 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 invention has for its object improvements in gauges for indicating small
amounts of vacuum or pressure, such gauges being specially applicable for
indicating the pressure of gas, the pressure of air in mines, or for showing the
differences of pressure in a ship's stoke hole and in the outer air, the draft into a
furnace or through a flue, and for other purposes.
We have illustrated our invention in the accompanying drawings, in which :-
Fig. 1 is a face view of a gauge capable of indicating small amounts of either
pressure or vacuum.
Fig. 2 is a face view of a gauge for indicating small amounts of pressure only.
Fig. 3 is a sectional front view, Fig. 4 is a vertical cross section and Fig. 5 is a
horizontal cross section, of a gauge for indicating pressure in two different places
by the aid of only one pressure chamber, and
Fig. 6 is a detail view showing the connection between the operating chamber
and the gearing employed for small gauges and for gauges. capable of showing
small amounts of either pressure or vacuum.
The operating chamber, gearing and connections between the same and the hand
or pointer being substantially alike in all the classes of gauges herein referred to,
we have not thought it necessary to repeat the drawings thereof for the various
gauges, but the description of those parts of the gauge shown at Figs. 3, 4, 5
combined with the other figs. will be sufficient to enable the invention to be
clearly understood.
We employ a metal chamber a formed somewhat similarly to that of an aneroid
barometer but not exhausted and which is very sensitive to either pressure or
vacuum. and we provide the same in some cases, see Figs. 1 and 2, with a conical
nozzle attached to a tube & communicating with the interior thereof and to which
a tube is attached by meaus of a corresponding conical fitting c, whilst in other
cases, see Figs. 3 and 4, a tube 6* may be rigidly attached to the tube b
communicating with such chamber a.
The chamber a may be used exclusively for indicating small amounts of pressure
or vacuum, or it may be used for indicating both pressure and vacuum.
In an instrument capable of use for indicating either pressure or vacuum and
suitable for indicating pressure of gas and other light pressures and vacuum, we
enclose a light sensitive chamber a in a suitable case d; this chamber a, by suitable
gearing as hereinafter described, gives motion to a hand or pointer which is

page_text: caused, by a spring w, normally to rest at the zero point on the face of the instru-
ment, see Fig. 1, which latter has a scale on each side of the zero point and is
provided with a stop y for the hand or pointer between the highest points of
such scales.
The case d of the instrument is, as before described, provided with a tube b com-
municating with the interior of the chamber and capable of connection with a pipe,
chamber or space, of which the internal pressure or vacuum is desired to be
ascertained.
"
By this arrangement the hand or pointer is caused to travel in one direction
round the face when indicating pressure, and in the opposite direction when
indicating vacuum.
If it is desired that an instrument should indicate only either pressure or vacuum,
the scale will be divided in one direction only, as indicated at Fig. 2, for either of
such purposes, and the hand or pointer & will travel only in one direction to
indicate the same, being returned to the zero point against a stop y by a
spring w.
Two instruments, consisting of similar chambers a with their gearing, hands or
pointers a, springs w and scales, may be combined in one case and one of them
used to indicate the pressure in a stoke hole whilst the other is used to indicate the
pressure of the external air; or a single instrument, as shown at. Figs. 3, 4, 5, may
be used for both purposes, in which case the chamber a and its connected parts will
be enclosed in an airtight case d and the chamber a will have a tube b connected
therewith which will be in communication with the stoke hole, whilst another
tube d communicating with the enclosed space within the case d around the
pressure chamber a will communicate with the external air.
The face of the instrument has a scale divided in one direction only from the
zero point, which will be readily understood by reference to Fig. 2. By this
arrangement, when communication with the outer air is shut off by a suitable tap
or valve on the pipe d', the pressure in the stoke hole causes the hand or pointer
to move forward to the proper division on the scale to indicate such pressure;
then, by opening communication, by means of such tap or valve, between the space
within the case of the instrument and the outer air, the latter will cause a certain
retrogression of the hand or pointer by which the difference of pressures is
indicated should any such exist.
The gearing and connections shown in the drawings communicating the motion
of the chamber a to the hand or pointer are arranged as follows. The chamber a is
fixed to a plate e, fixed rigidly within the case d, by means of a central neck or
stud a', as shown at Figs. 4 and 5; or said chamber may be fixed in position by
means of two or more studs around its periphery passing through holes in brackets
fixed to the plate e, as will be readily understood.
To a cross bracket or bridge piece e fixed to the plate e, are attached pillars e
provided with pivotting screws es, between which is mounted the axis fcarrying a
lever resting against the stud a² fixed to the chamber a and passing through a
hole in the bridge piece e'. The axis falso carries a stud or lever to which one
end of a chain g is attached, the other end of such chain being attached to a small
pulley fixed on the axis h. On this axis is fixed a toothed wheel /³ which
gears into a pinion on the axis of the hand or pointer x. A spiral spring w
attached at one end to the axis i, and at the other end to one of the pillars k¹
carrying the outer bearing plate of the axis i, serves to return the hand or
pointer to the zero point after having been moved therefrom by the motion of
the chamber a.
In order to obtain great accuracy of action, the wheel and pinion i¹ may be.
replaced by pulleys and a chain connected at its ends to such pulleys and winding
from the one on to the other, as will be well understood.
For small gauges and for such as are required to indicate both pressure and
vacuum, we connect the lever to the stud a' by a link, as shown at Fig. 6, or
other suitable connection may be used.

page_text: The gearing and connections between the chamber a and the hand or pointer
have been found to answer well, but other suitable arrangements of gearing and
connections may be employed for such purpose.
The action of the moving parts herein described is as follows.
On the chamber a being subjected to a greater or less pressure or vacuum
beyond the normal, it will move the lever f¹, and consequently the axis and stud
or lever, which, by the chain g, will give motion to the axis h, which latter; by
the gearing described, will give motion to the axis i and consequently to the band
or pointer x.
When using the improved pressure gauge for determining the draught in a flue,
the tube communicating with the interior of the chamber a is led into such flue
with its open end in a direction to meet the draught, which latter, by entering the
pressure chamber
will cause the gauge to indicate the pressure produced by
such draught.
a,
Having now particularly described & 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
1. The improved gauges for indicating small amounts of pressure or vacuum,
substantially as herein shown and described.
2. In gauges for indicating small amounts of pressure or vacuum, the peculiar
arrangement and combination of parts, substantially as herein shown and described
in reference to Figs. 3, 4, 5.
Dated this 10th day of September 1894.
GEORGE V. FOSBERY,
JAS. J. HICKS,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.