Year: 1887

page_text: Date of Application, 13th Apr., 1887
Complete Left, 12th Jan., 1888
Complete Accepted, 17th Feb., 1888
GEORGE SMITH 45 West Nile Street Glasgow North Britain Merchant, do
hereby declare the nature of this invention to be as follows:-
:
My Invention has for its object the improved construction of apparatus for indi-
cating or recording pressure under conditions wherein the ordinary pressure indicators
are inapplicable as for instance in indicating or recording the pressure of the
atmosphere at a point where the pressure of the air is less than that at the sea level:
or, for indicating and recording the pressure of a fluid at a point where the pressure
is in excess of the atmospheric pressure.
My improved apparatus essentially consists in utilizing any known form of
pressure indicator, but more particularly the well-known Bourdon pressure gauge,
and enveloping same in a hermetically sealed chamber: the channel or communi-
cation from the indicator, which is usually connected to the generator, being in this
case open to the atmosphere or fluid in which the chamber with its indicator is
enveloped, while the casing serves to protect the mechanism and adjacent parts from
fluctuations in pressure and at the same time serves to maintain a constant or nearly
constant starting or zero point.
In applying the Bourdon coil, or curved tube as a means of indicating the pressure,
I construct the chamber, in which the coil is placed in one or more parts, preferably
but not essentially with one side or face provided with a frame or door, in which is
fitted a transparent dial or body. Or, the transparent dial may form part of the
chamber by being fitted into the casing air tight by any known mode. The aforesaid
chamber is further provided with a comparatively small outlet, provided with a plug
or cap, to hermetically close said outlet at pleasure.
The coil or curved tube with the mechanism commonly employed for showing the
amount of deflection or motion of the tube is fitted inside the chamber, the neck or
extremity of the hollow coil or tube which serves as a channel or communication with
the generator connecting pipe being in this case securely attached to the side of the
chamber or casing in such a manner that while the nose or outlet is in com-
munication with the air or fluid outside the chamber, said air or fluid cannot pass
into the chamber at the point where the neck is jointed to the side of the chamber
The central spindle, which is set in motion by the toothed segment, actuated by the
curved tube, may be provided with the customary pointer or by an arm which at the
same time changes the position of a tell tale pointer or pointers, which pointers only
037

page_text: travel in one direction, and serve as a means of recording the extreme pressure to
which the chamber has been subjected. The tell tale pointers either revolve on the
main spindle hereinbefore referred to, and are caused to return to the starting point
by means of another needle or lever, having its axis in line with the capped aperture
already described, or the guiding or governing pointer or needle has its axis or
spindle passing through the centre of the main spindle, the main spindle thus
becoming a hollow spindle. In either case the extremity of the governing spindle,
that is the axis of the pointer or needle, which is employed to cause the tell tale
pointer to return to its starting point, may be fitted with a key seat or other
means to enable a key or other contrivance to be employed in guiding the direction
of the spindle referred to or, the spindle may pass sufficiently clear of the chamber to
enable a cap or head being fitted to the extremity, much in the same manner as the
winding spindle or axis in a self winding or keyless chronometer.
The apparatus hereinbefore described, with or without, the tell tale arrangement,
may have the neck or open end of the hollow or curved tube terminating in a
chamber in which is fitted a check valve of any known form or design, which valve
serves to regulate the flow of the fluid or fluids into or from the aforesaid chamber.
The valve being so arranged that on the pressure being partially released and in
consequence the fluid or fluids in the chamber tending to pass outwards or inwards as
the case may be, the valve closes the passage and prevents further escape of the fluid
or fluids, the pressure in the chamber being maintained at or near the maximum or
extreme point to which the apparatus has been subjected, it follows the indicator
needle will register the pressure existing in the chamber, and at the same time
indicates the extreme pressure to which the gauge has indicated.
To permit the needle to return to zero or its starting point, the apparatus is provided
with suitable mechanism to release the check valve, thereby equalizing the pressures.
The check valve has a tendency to stick or remain partially open when the return
current takes place, thereby tending to inaccurate indications: To guard against this
action, the valve may be loaded, preferably by means of a coiled spring, to cause the
valve to remain close to or bear against its seat, when the external and internal
pressures are nearly equal.
Instead of the check valve arrangement hereinbefore described I may maintain the
maximum pressure in the pressure indicator proper, by employing any known form
of cock or valve, which is fitted to the passage leading to the hollow coil or tube
already referred to, said cock or valve being employed to regulate the flow of the
fluids in the passage, and being actuated by wings or vanes placed outside the
chamber or mechanism in such a manner that the resistance of the fluid thro' which
the apparatus is passing, determines the position of the vanes. In ascending thro' the
atmosphere the resistance due to the air, would cause the extreme edges of the vanes
to point in an opposite or nearly opposite direction. In returning, the vanes would
take up the reverse position and in doing so, actuates the cock or valve which closes
the passage intermediate to the Bourdon coil or tube and the atmosphere thereby
preventing more air to enter the chamber in the descent of the apparatus. The
reverse action would take place in taking indications of pressure in sounding.
The check valve arrangement or mode of closing the valves by means of vanes or
corresponding contrivance, may be applied to any known form of pressure indicator,
in addition to the Bourdon gauge hereinbefore referred to.
The valve faces may in time become irregular thro' grit or solid bodies passing
thro' the channel, to prevent this taking place, 1 may employ an air chamber
intermediate to the valve and the mouth of the channel, of sufficient capacity to
prevent any of the liquid which enters the channel passing thro' the valve.
Dated this 8th dox of Annil 1007

page_text: An Improved Apparatus for Indicating or Recording Pressure.
I, GEORGE SMITH, of 45 West Nile Street, Glasgow, North Britain, Merchant, do
hereby declare the nature of my invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement in writing, reference being had to the accompanying Sheet of Drawings,
and to the letters and figures marked thereon, that is to say :-
My said Invention has for its object the improved construction of apparatus for
indicating or recording pressure under conditions wherein the ordinary pressure
indicators are inapplicable; as, for instance, in indicating or recording the pressure
of the atmosphere at a point where the pressure of the air is less in the zenith than at
the sea level; or for indicating the pressure of the sea or of a fluid at a point where
the pressure is in excess of the atmospheric pressure below the sea level towards the
centre of the earth.
My improved apparatus essentially consists in utilising any known form of pressure
indicator, as the corrugated disc indicator, but more particularly the well-known
Bourdon pressure tube gauge, and enveloping same in a hermetically sealed chamber;
the channel or communication from the interior of the acting tube of the indicator,
(which is usually connected to the generator, the pressure in which is to be indicated)
is in this case open to the atmosphere or fluid in which the chamber with its indicator
is to be enveloped while acting; the whole lower part having a conical or other
outer casing serving to protect the mechanism and adjacent parts or fittings from
fluctuation in pressure and injury to the parts, and at the same time serves to
maintain a constant or nearly constant starting or zero point, indicating the pressure
at the sea level.
The nature of the invention consist as follows:-I apply a Bourdon coil or curved
tube as a means of indicating the pressure, and construct the chamber, in which the
coil is placed in one or more parts, preferably but not essentially, with one side or face
provided with a frame or door, in which is fitted a transparent disc or dial or body,
or the transparent dial may form part of the chamber by being fitted into the casing
air-tight by any ordinary known mode and means. The aforesaid chamber is further
provided with a comparatively small outlet provided with a plug or cap to hermetically
close said outlet at pleasure.
The coil or curved tube with the mechanism connected and employed for showing
the amount of deflection or motion of this tube is fitted inside the chamber, the neck
or extremity of the hollow coil or tube which serves as a channel or communication
with the generator connecting pipe being in this case securely attached to the side of
the close chamber or casing in such a manner that while the nose or outlet is in
communication with the air or fluid outside the chamber, said air or fluid cannot
pass into the enclosing chamber at the point where the neck is jointed to the side of
the chamber. The main central spindle, which is set in motion by the toothed
segment and connecting pinion actuated by the curved tube, is provided with the
customary pointer, or an arm, which may at the same time change the position of a

page_text: tell-tale pointer or pointers, which main pointer or tell-tale pointers are moved in one
direction, and serve as a means of recording the extreme pressure to which the internal
chamber of the indicator has been subjected.
The apparatus herein before described, with or without the tell-tale arrangement,
would have the neck or open end of the hollow or curved tube terminating in a
chamber in which is fitted a check valve of any known suitable form or design, which
valve serves to regulate the flow of the fluid or fluids into or from the aforesaid
chamber. The valve being so arranged that on the pressure being partially released
and in consequence the fluid or fluids in the chamber tending to pass outwards or
inwards as the case may be, the valve closes the passage and prevents further escape
of the fluid or fluids, the pressure in the chamber being maintained at or near the
extreme point or maximum to which the apparatus has been subjected, it follows that
the indicator needle will register the pressure existing in the chamber, and at the
same time indicate the said extreme pressure to which the gauge has been subjected.
To permit the needle to return to zero or its starting point, a relief screw or
equivalent hand valve is fitted on the close generating pressure chamber, opening this
valve, thereby equalising the pressures. The check valve has a tendency to stick or
remain partially open when the returning current takes place, thereby tending to
inaccurate indication. To guard against this action, the valve may be loaded,
preferably by means of a coiled or other spring, to cause the valve to remain close to
or bear against its seat when the external and internal pressures are nearly equal.
The valve faces may in time become irregular through grit or solid bodies passing
through the channel, to prevent this taking place, I may employ an air chamber
intermediate to the valve and the mouth of the channel of sufficient capacity to
prevent any of the liquid which enters the channel passing through the valve.
an
And in order that my said invention and the manner of performing or carrying the
same into effect or practice may be properly understood, I have hereunto appended
explanatory Sheet of Drawings, in which the same reference letters are used to
indicate corresponding parts in all the Figures where shown.
Figure 1 is a sectional elevation of one construction or arrangement and
combination of the parts of a pressure indicating and recording apparatus, made as a
sounder or instrument for taking the pressures and corresponding soundings of the
sea below sea level, or depths of other waters or fluids below their normal surface level
and pressure thereat; all constructed in accordance with and illustrative of one
modification and application of the improvements of my invention. Figure 2 is a
plan, with carrying top A³ removed, showing the divided dial plate a², and index
pointer a'. Figure 3 is a sectional plan taken near the line 1---1 Figure 1, showing
the close hollow pressure acting tube B and the gearing mechanism 6 to 64, by which
it actuates the index pointer a and main spindle a¹, as hereinafter described. Figure 4
is a sectional elevation and plan of the inlet valve seat D, and its valve disc d as
detached therefrom, to illustrate its construction more clearly than in Figure 1.
Figure 5 is a sectional elevation of the improved lower or pendent inlet tube or vessel E,
and its valve seat D, and fittings for transmitting the pressure of the outer fluids
to the interior of the acting (or expanding and contracting) tube B, slightly different
or modified from that shown in Figure 1. Figure 6 shows a sectional elevation of the
instrument as constructed, or modified, in accordance with the improvements of this
invention for taking or indicating and recording the pressures and corresponding
altitudes, lighter and higher respectively, than that at and above the sea-level.
Referring to the instrument for taking the soundings or depths below the sea-level
shown in Figures 1 to 4 of these Drawings, the apparatus consists of a close circular
case or chambered vessel A which has mounted within it the close elliptical Bourdon
coiled pressure acting tube B, rigidly secured by its block end B¹ and screw stem B2
and jointing collar base B" to the close bottom A¹ of case A, where it is jointed fluid
pressure tight by the upper screwed socket of the valve chamber piece C. As seen
particularly in Figures 1 and 3, the free working end of the acting pressure tube B is
connected by a link 6, to the outer lever end of the toothed sector 6', on a spindle at b²
oscillating in bearings in the base-plate 63 and bracket 64 screwed thereto, so that the

page_text: toothed segment b' actuates a pinion 6" on the spindle a of the index pointer a
rotating in the basement plate 63 and bracket 6111, so as to act essentially in the
manner of the Bourdon gauge by the pressure of the air or fluid admitted by the tube
or channel c to the interior of the elastic acting tube B; but by these improvements
all enclosed fluid tight within the case A, which would have a small screw plug at a³
to admit the outer pressure of air to this close case. The pointer a with the dial
plate a² below it are enclosed visibly below another glass or transparent top plate or
disc A preferably jointed tight within the upper end of the case A, by screw
rings AA with insertion or india-rubber joint rings all all between them, and
all carried by an open armed ring A³ screwed to the top of the case A, and having a
strong centre eye at A, to which a light rope or wire would be attached for lowering
and raising the whole instrument in the sea or other waters, where the depth or
sounding had to be taken. The index dial a², shown divided from zero up to
80 fathoms and corresponding to the pressure above that of the atmosphere at the
sea-level, and which would be given within the tube B by the pressure of the sea-
water at any of these depths to turn the pointer a to any of their respective divisions
on the dial; and the dial might also be divided on an outer circle at a to give the
corresponding pressure in pounds or in inches of mercury when that is desired.
The inlet pressure valve chamber or socket C, with the small tubular duct c leading
through the stem B2 and chamber block B¹ B, to the interior of the close pressure
acting tube B, has the inlet or check valve stem seat piece D screwed fluid tight
within its chamber C', fitted with a valve d to open inwards over its top end. The
valve d might be fitted in various suitable known ways, to open inwards with a very
slight pressure, and therefore to suit this purpose, closed perfectly, to maintain the
pressure within, by the action of a very light spring. One construction of valve,
which I find to answer well, consists of a very light turned disc of brass d, made to
close on a turned recess seat d¹ of about the same depth as shown detached in
Figure 4, but fitted as seen for action in Figures 1 and 5, the disc is enclosed
between two thin layers or narrow strips of oiled silk d², strapped across or over the
seat d¹, to close accurately over it, secured by a fine thread or wire in the edge groove
at D' for the purpose. To ensure the free closing and opening as stated, a thin
narrow band of vulcanised india-rubber d³ is similarly secured over the said valve d
preferably across the silk strap d', as dotted in Figure 4; or instead of this rubber
spring d³, a very light spiral spring d might be used, as shown in Figure 5. This
valve seat piece D is formed with a small inlet tubular hole c¹ through it, and has
screwed tight to its lower end an inlet fluid pressure acting tubular chamber E open
at the lower end E¹, formed with inlet holes e, and fitted with a wire protecting
sieve E to admit the water free of grit or other matters, and produce the pressure
inside the tube E which is outside. Sufficient air is always left in the upper part of the
tube E to act and give the pressure through the ducts c, c¹, in the valve chambers D, C,
and within the coil tube B, without the water requiring to pass through the
valve d, or these working parts of the instrument C, B although this chamber E is
not absolutely necessary. A small hand relief screw valve plug 02, is fitted in the
one side of the valve socket C, above the valve d, d', with escape ports c², to the
atmosphere to be opened after each use of the instrument, the arrows in the sectors
indicate the inlet of the water or fluids for giving the pressure action within the
instrument, and for the relief of the pressure when the plug ( is used. The said
lower valve chambers C, D, and inlet pressure tube E, are preferably enclosed in a
protecting metal case F, with a ring or eye F¹ at the lower end for attaching a lead
or other weight to the whole when the weight of the instrument is not sufficient to
insure its steady vertical descent; this descent is assisted in the sounding
instruments Figures 1 and 5, by making this lower outer case F of an inverted
conical shape.
.
As before stated, Figure 5 is a modification of Figure 1, for taking soundings, in
which no special separate hand relief valve 02 is fitted, but has a spindle C³ with
finger knob C below, fitted through a cap E³, with stops e¹, e², in the centre of the
lower inlet chamber É and valve seat D, so as to be pushed up and open the valve d

page_text: and relieve the pressure within the acting coil tube B, after each use and indication
of the instrument, in an equivalent manner to that described in reference to using the
screw plug valve C²; the inlet valve d in this case being fitted with a light spiral
spring d in place of the india-rubber spring d³, shown in Figures 1 and 6. Referring
to the modification of the apparatus shown in Figure 6 for taking pressures and their
corresponding altitudes above the level of the sea, as up mountains, or for being used
in balloons, the main actuating parts of the instrument within the close case A are all
substantially the same as described in reference to Figures 1 to 3, except that the
index would be divided for feet or fathoms above the level of the sea, corresponding
to the decreasing pressure of the atmosphere, and consequently the pressure tube B
would act by suction or vacuum ; and as a consequence the valve seat D is fitted on
the lower end of the inlet air chamber E, and has the check valve d fitted on the outer
end of its seat D to allow of the escape of air from the inside on its ascent and close
by the outward pressure of the atmosphere so as to give the maximum height obtained
at each action and use of the instrument, a small hole e, admitting the pressure of air
to the valve d. The outer case F with its steadying weight eye F¹ below, is in this
case shown cylindrical and close at the lower end, the pressure of air to the instrument
being admitted through the opening f, for getting at the screw plug valve C², for
admitting the air to destroy the vacuum after each use of the instrument; otherwise
the instrument is constructed and acts substantially as described in reference to the
former Figures.
Having thus particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, 1 declare that what I
claim is,
First. The construction or arrangement and combination of the parts of a new or
improved instrument or apparatus for indicating or recording pressures and corre-
sponding depths or heights below or above sea-level, substantially_as herein
distinguished in reference to the respective Figures of the accompanying Drawings.
Second. In apparatus for indicating or recording pressures and corresponding
depths and heights below and above sea-level, the enclosing of a pressure acting
tube B and its actuating index mechanism or other equivalent pressure indicator
within a close air vessel A, combined with a tube stem C, D, or valve chamber C¹,
and its check valve d, fitted as described, and air pressure chamber E, substantially as
herein distinguished in reference to and shown in the accompanying Drawings.
Third. In apparatus for indicating or recording pressures and corresponding
depths and heights below and above sea-level, the fitting of a valve chamber and
seat C, D, d, with a delicate elastic spring actuating check valve d, d², d³, or other
equivalent valve, and either with or without an air pressure chamber E, substantially
as herein distinguished in reference to and shown in the accompanying Drawings.
Fourth. In apparatus for indicating or recording pressures and corresponding
depths and heigths below and above sea-level, the fitting of an air pressure
chamber E, either on the outside or the inside of the check valve d, as described and
distinguished in reference to Figures 1 and 5 or 6 of the accompanying Drawings.
Fifth. In apparatus for indicating or recording pressures and corresponding
depths and heights below and above sea-level, the fitting of a hand relief valve C², or
its equivalent rod C³, for relieving the pressure within the instrument on the inside of
a check valve d, substantially as herein distinguished in reference to the accompanying
Drawings.