Improvements in Pressure Gauges.
Year: 1898

page_text: Date of Application, 12th Mar., 1898
Complete Specification Left, 12th Dec., 1898-Accepted, 7th Jan., 1899
Improvements in Pressure Gauges.
WILLIAM HENRY THOMPSON and ROBERT THOMPSON, 155, l'enchurch Street,
London, E.C., Engineers, do hereby declare the nature of this invention to be
as follows;-
In carrying our invention into practice we arrange the Bourdon or spring
tube in connection or combination with a cylinder arranged in or formed in com-
bination with the gauge case in such a manner as to admit of the open or inlet
end of the Bourdon tube opening into a passage formed in or near the bottom
of the cylinder so as to adinit of water or other liquid with which the cylinder
may be charged rising to the same level in the Bourdon tube as in the cylinder
the bottom end of which terminates with a screw hereinafter called the union
screw, which screw is formed with a hollow passage connected with and opening
into a tube hereinafter called the cylinder tube extending upward through the
cylinder from the bottom and terminating above the Bourdon tube the cylinder
being of such height as to admit of sufficient space above the top end of the
cylinder tube for an accumulation of grease or other substance (hereinafter men-
tioned) being discharged from it as hereinafter mentioned, the top end of the
cylinder being sealed by a screw cover or other suitable sealing device. Our
object being to employ the gauge for indicating pressure acting on grease or other
plastic or semi solid substances of lighter specific gravity than water which sub-
stances if acting directly on the Bourdon tube are liable to choke or compress in
it to such an extent as to prevent its proper operation; we charge the said cylinder
with water until it has reached such a level in the cylinder as to fill the Bourdon
tube with which it is connected as aforesaid and rise above it so as to be at or
near the level of the top end of the cylinder tube, the operation being as follows:--
The gauge being connected by means of the union screw to the chamber or
apparatus containing the grease or other substance aforesaid under pressure
which pressure causes such substance to rise in the cylinder tube by which it is
discharged on to the surface of the water contained in the cylinder until the space
above the cylinder tube or between the water and the cylinder cover becomes
charged and the pressure is communicated both to the water in the cylinder and
Bourdon tube so as to operate the latter by which operation the pressure is
indicated in the usual manner.
Other suitable liquids of greater density may be substituted for water.
When the substance under pressure may be of such a nature as to absorb the
water and sink in the cylinder or rise in the Bourdon tube, or when it may be
otherwise expedient we arrange the Bourdon tube in an inverted position so as
to retain the water or liquid with which it may be charged, and admit of its open
end or inlet aperture being connected with an aperture opening into the cylinder
near the top of it, leaving sufficient space between such aperture and the top of
the cylinder for the water to be charged in the cylinder at a suitable level above

page_text: the said aperture and the cylinder (instead of being provided with the cylinder
tube extending through it as aforesaid) is provided with a piston fitting it in
such a manner as to traverse it and at the same time form à partition between
the grease or other substance aforesaid and the water in the cylinder and Bourdon
tube so that when they are both charged, the grease under pressure acts on the
piston in such a manner that the said pressure is communicated to the water afore-
said so that it operates the Bourdon tube which in its movement indicates the
pressure as aforesaid, any grease escaping past the piston will rise in the water
past the aperture leading to the Bourdon tube and collect on the surface of or in
the water above so that by the removal of the cover sealing the cylinder such col-
lection may be readily removed and any waste of water replenished, the sealing
cover replaced the gauge is again ready for operation.
The aforesaid arrangement of parts for intercepting the water or other fluid
from the grease or other substance aforesaid may be adapted to other devices
for operating the gauge indicating mechanism (besides the Bourdon tube) to which
it may be applicable."
D-1
Al
1
1000
WM. H. THOMPSON.
ROBT. THOMPSON.
WILLIAM HENRY THOMPSON and ROBERT THOMPSON, 155, Fenchurch Street,
London, E.C., Engineers, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
Our invention has for its object improvements in pressure gauges whereby their
operation and indications are rendered more reliable and accurate when employed
for indicating the pressure acting on grease and semi solid or plastic substances
such improvement being more particularly applicable to gauges in which the
Bourdon tube is employed for operating the index hand or mechanism indicating
the pressure.
In carrying our invention into practice we arrange the Bourdon or spring
tube A in connection or combination with a cylinder B (Figs. 1 and 2) of acco
panying sheets of drawings which cylinder is preferably formed in combination
with the gauge case C in such a manner as to admit of the open or inlet end I)
of the Bourdon tube opening into a passage E leading from the cylinder so as to
admit of the water (or other liquid) with which the cylinder may be charged
flowing into and rising in the Bourdon tube until it is charged as hereinafter
mentioned.
The bottom end of the cylinder terminates with a screwed end or shank (herein-
after called the union screw) F' which is formed with a passage for connection
with the tube G (hereinafter called the cylinder tube) which extends upwards
from its connection with the bottom of the cylinder so as to terminate at such a
height above the level of the Bourdon tube (or the water contained therein) as
to deliver the grease or plastic substance on the surface of the water contained in
the cylinder (as shown) and leave a space between the screw cover H (sealing
the cylinder) and tube G sufficient for an accumulation of grease as hereinafter
mentioned.
We charge the cylinder B with water (or other liquid) until it fills the Bourdon
tube as aforesaid and rises above it so as to be level or nearly so with the top end

page_text: of the cylinder tube G. The operation being as follows:-The gauge being con-
nected by means of the union screw F to the chamber or apparatus containing
the grease (or plastic substance) under pressure which pressure causes the grease to rise
in the cylinder tube G by which it is discharged on to the surface of the water
contained in the cylinder until the space I above the tube G or between the water
and the cylinder cover H becomes charged with grease under pressure, which
pressure is communicated to the Bourdon tube through the medium of the water
on which the said grease acts so that its pressure operates the Bourdon tube,
the motion of which is transmitted by mechanism (as shown) to an index hand
so as to radiate it over a dial indicating the pressure in the usual manner.
When the grease or substance under pressure may be of such a nature as to
absorb the water, and sink into the cylinder and choke the Bourdon tube A,
or when it may be otherwise expedient we arrange the said tube in an inverted
position (as shown in Figures 34 and 5) so as to retain the water or liquid with
which it may be charged and admit of its open end or inlet aperture D being
connected with the passage E opening into the cylinder B near the top of it,
leaving sufficient space I between the passage E and the cylinder cover H so as
to form a cavity for the water to be charged into the cylinder at a suitable level
above the passage E and the cylinder (instead of being provided with the tube G
as shown in Figure 1) is provided with a piston J fitting and working in it in
such a manner as to form a moving partition between the grease or other substance
aforesaid and the water in the cylinder, which water is shown above the piston,
which, when under the pressure of the grease shown below it, transmits the pressure
of the grease to the Bourdon tube, through the medium of the water; the motion
of the said tube resulting from the pressure on the water indicates the pressure
on the grease by means of an index hand and dial as shown.
The arrangement is such that any grease escaping past the piston J will rise
in the water past the passage E and collect on the surface of the water in the
cavity above the passage so as to be clear of the Bourdon tube A, so that, by the
removal of the cylinder cover, such collection may be readily removed and any
waste of water replenished, the cylinder cover being replaced, the gauge is again
ready for operation.
The arrangement of the Bourdon tube A may be varied so as to be adapted
to modifications and variations in the design of the gauge; also the arrangement
and combination of cylinder B and the tube G or passage formed by it, also
cylinder cover H and passage E or cylinder B and piston J and cover H and parts
(by which the fluidity of the water or other liquid is utilized to operate the Bourdon
tube) may be adapted for the operation of other pressure gauge indicating mechan-
ism for which it or they may be applicable for indicating the pressure exerted
on grease or other semi-solid or plastic matter without departing from the substance
of our invention.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare what
we claim is: —
Firstly.—We claim the arrangement and combination of the cylinder B tube G
and moveable cover H with the Bourdon tube A and index hand and dial and
other mechanism and parts so as to form a pressure gauge in which the fluidity
of water or other liquid is utilized for operating the Bourdon tube and thereby
indicating the pressure exerted on grease or other semi-solid or plastic substances
or matter substantially in the manner herein described and shown by Figures 1
and 2 of the accompanying sheet of drawings.
Secondly. We claim the arrangement and combination of the cylinder B
and piston J and moveable cover H with the inverted Bourdon tube A and index
hand and dial and other mechanism and parts so as to form a pressure gauge in
which the fluidity of water or other liquid is utilized for operating the Bourdon
tube and thereby indicating the pressure exerted on grease or other semi-solid

page_text: or plastic substances or matter substantially in the manner herein described
and shown by Figures 3, 4, and 5 of the accompanying sheet of drawings.
Lastly. We claim the arrangement and combination of the cylinder B and
tube G and moveable cover H or cylinder B, piston J, and moveable cover H with
the Bourdon tube or other mechanism or parts operating the index hand &
forming a pressure gauge in which the fluidity of water is utilized as a medium
for operating the mechanism for indicating the pressure exerted on grease or
other semi solid or plastic substances or matter substantially in the manner herein
described and shown by the figures in the accompanying sheet of drawings.
Dated this Twelfth day of December 1898.
WM. H. THOMPSON,
ROBT. THOMPSON.