Improvements in Pressure Gauges.
Year: 1894

page_text: Date of Application, 13th Apr., 1894
Complete Specification Left, 24th Oct., 1894-Accepted, 1st Dec., 1894
I JOHN HILL of Hollings Street Fenton Stoke on Trent Mechanical Engineer
do hereby declare the nature of this invention to be as follows:-
This invention has reference to pressure gauges, such as indicate the pressures of
steam boilers, or other pressures.
The chief feature of this invention consists in so constructing the said apparatus,
that any variation of pressure of steam in the boiler, will actuate the hand of the
pressure gauge, and so indicate the pressure upon the dial, or show it through the
glass cylinder, or tube by the moving of the piston, or the rise and fall of
the water.
An apparatus constructed according to this invention consists of a cylinder,
twice the length of the piston, the cylinder to be made of glass or brass, or other
suitable material, the piston to be made of hard wood, or other suitable material,
the piston ring is to consist of a round elastic ring, to form the packing between
the piston and cylinder, to roll up and down the cylinder, (as in a Kennedy water
meter) to actuate a horizontal spindle by means of a rack, and pinion or other
suitable gear, the spindle to extend through a stuffing box at the front so as to fix
the hand of the pressure gauge, to indicate the pressure upon the dial, as in the
ordinary gauge, or to show it through the glass cylinder by the rise and fall of
the piston or the rise and fall of the water, the index to be engraved on
the cylinder or tube or on a frame on one or both sides of the cylinder or tube.
The bottom side of the cylinder to be connected to the boiler by means of
pipes, the top side to be sealed, so as to compress the air as the pressure of the
boiler forces the piston up, and the air so compressed is to force the piston down
as the steam lowers in pressure.
Improvements in Pressure Gauges.
I, JOHN HILL, of Hollings Street, Fenton, Stoke on Trent, Staffordshire,
Mechanical Engineer, 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 :-
This invention has reference to pressure gauges such as indicate pressure of
steam boilers or other pressures.
This invention consists in so constructing the said pressure gauges that any
variation of pressure of steam in the boiler will by a piston actuate the hand of the
pressure gauge and indicate upon the dial the pressure of the steam, or shew the
pressure through a glass cylinder or tube by the movement of the piston therein,
or will shew the pressure by the rising and falling of the water contained in a glass
cylinder or tube.
I may arrange my invention in various ways as I will now describe by referring
to the accompanying drawings on which
Fig. 1 is a sectional side elevation and Fig. 2 is a sectional front elevation of
one form of pressure gauge constructed according to this invention;

page_text: Fig. 3 illustrates another form of my invention; Fig. 4 illustrates another form
of the same;
Fig. 5 is a sectional 'elevation of another arrangement of my invention and Fig. 6
shews another arrangement of the same.
The same letters of reference indicate the same or corresponding parts in all the
figures of the drawings.
1 will first describe the arrangement of my invention illustrated by Figs. 1 and 2.
In this arrangement of my invention I employ a cylinder A made of glass, brass or
other suitable material and made of about twice the length of the piston B contained
therein this piston being made of hard wood or other suitable material and provided
with a piston ring C which forms the packing between the piston and the cylinder
this ring being arranged to roll up and down the cylinder on the piston between the
flanges c¹ c³ of the piston as in what is known as a Kennedy water-meter. Fixed
to the piston is a rack D which gears with a pinion el fixed on the spindle E so
that as the piston moves up and down the spindle E will thereby be turned in the
one or the other direction. Or instead of the said rack and pinion any other suitable
arrangement of gearing may be employed. The spindle E extends through a
stuffing box Q at the front of the pressure gauge and has fixed on it the hand G
of the pressure gauge so as to indicate the pressure upon the dial F as in an
ordinary gauge. The top side of the cylinder A is sealed air tight by the cover H
which is made with an upwardly projecting chamber h¹ for the rack D to rise and
fall in. The bottom side of the cylinder A is connected by a pipe at i to the boiler
either above or below the water line so that either steam or water from the boiler
will enter the cylinder A below the piston B and force the piston upwardly, until
the compressed air in the cylinder A above the piston B is of the same pressure
as the steam in the boiler which pressure will be indicated on the dial F by the
finger G. When the pressure in the boiler falls the compressed air above the
piston forces the piston down until equilibrium has been again attained when
the finger G will indicate the reduced pressure.
The parts shewn by Figs. 1 and 2 are made of metal but it will be evident that
if the cylinder A be made as a glass tube the rack pinion spindle dial and finger
and cover H may be dispensed with and as the piston will then be visible from the
outside of the cylinder or tube A its rising and falling will indicate the pressure of
the steam by an index or scale engraved on the cylinder or tube or fixed
conveniently near to the same as for instance in an ordinary thermometer.
This
In the arrangement of my invention shewn by Fig. 3, I employ a floating rod J
which corresponds to the piston A and is arranged to move easily in the glass tube
or cylinder A which is air tight at the top, and at the bottom is fixed to the lower
cylindrical portion A' which in this case is made of metal and connected at its bottom
side at i by the syphon pipe to the boiler K above the water line k.
syphon is in all cases made large enough to contain as much water as the
cylindrical vessel A so as to always ensure a supply of water for filling the latter.
The pressure of the steam in the boiler will force the water along the pipe into
the lower portion A' of the cylinder and compress the air above the water and
in the tube A until equilibrium has been attained when the top of the floating
rod J will by its position in the glass tube A. and relatively to the scale F shew the
pressure of steam in the boiler. "In order to reduce the distance through which the
float or rod J will have to travel the lower part A' of the cylinder is by preference
made conical as shewn much larger at the bottom than the top so as to make the
rise of the floating rod J as nearly uniform as possible for uniform rises in
the pressure.
Fig. 4 shews a further modification of my invention in which instead of the glass
tube A being arranged above the lower cylindrical portion A' the glass tube A is
arranged by the side of the cylindrical portion A' and the tube A is in this case
open at the top and bottom to the top and bottom of the conical cylindrical part A'
so that as the water rises in the conical cylinder A¹ and compresses the air therein
the air is similarly compressed in the glass tube A in which the water also rises

page_text: to the same level as in the cylinder A' and thus the rise and fall of the water m
the glass tube A will by the graduated scale F indicate the pressure of the steani
in the boiler.
Fig. 5 shews a further modification of my invention in which the conical
cylinder A is itself made of glass and closed at the top and secured steam tight on
a base A' which can readily be done by making the cylinder A' with an outwardly
projecting flange a' which fits between packing rings in a recess on the plate A
and is there secured by a metal ring a which forces the packing rings against the
flange a¹ and makes a steam tight joint. This base A³ is provided with the hole i
to which the pipe is fixed for connecting to the boiler so as to admit water from the
boiler to the cylinder A' and then the rise and fall of the water in the cylinder A¹
compressing the air in the upper part of the cylinder will shew the pressure of the
steam in the boiler the pressure being indicated by the position of the level of
the water in the cylinder A relatively to the scale which is engraved or otherwise
marked or applied to the conical cylinder A¹.
In order to render more clear the variations in the level of the water or liquid
in the cylinder A' this may be coloured and then in order to prevent this coloured
liquid escaping to the boiler I arrange the apparatus as shewn by Fig. 6 where it
will be seen that the conical glass cylinder A¹ is made with a neck at the bottom a
fitting steam tight in a stuffing box m' on the top of a vessel M which contains the
coloured liquid. n is a small tube which is carried from the neck of the conical
glass cylinder A' almost down to the bottom of the vessel M. The upper part of
this vessel M is connected by a pipe o to another cylindrical vessel P the lower
of
part p' of which is connected by the pipe i to the boiler K so that the
pressure
the steam in the boiler K will force the water into the cylinder P as shewn com-
pressing the air above the level of the water and in the upper part of the cylinder M
and this compressed air acting upon the coloured liquid in the cylinder M forces
the said coloured liquid up the small pipe n' into the conical cylinder A¹ also
compressing the air therein so that as stated above the level of the coloured
liquid in the conical cylinder A' will indicate the pressure of the steam in the
boiler. The object of employing the two vessels M and P is to prevent the water
from the boiler mixing with the coloured liquid in the cylinder M.:
Instead of the glass cylinder A¹ being made conical as above described this
cylinder may as shewn for instance by Fig. 7 be made stepped at regular intervals
so as to be of gradually decreasing diameter towards the top and thus indicate the
gradual increase of pressure as the water or liquid rises in the cylinder and
compresses the air above it.
The accompanying drawings illustrate what I consider to be the best ways of
carrying my invention into practice but it is to be understood that my invention is
not limited to the precise details shewn as these may be varied slightly without
departing from the spirit of my invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a pressure gauge, a closed cylinder or tube containing air and a piston, said
cylinder having an inlet so arranged that when the water or other fluid under
pressure is admitted by the inlet to the cylinder or tube the piston will move and
compress the air on the other side of the piston and thus indicate the pressure by
the position of this piston in the cylinder or tube, said piston being either
combined with an index finger and dial or used without the index finger and dial
substantially as hereinbefore set forth.
2. The hereindescribed improved pressure gauge consisting essentially of a
conical or other cylinder or tube closed at the top and containing air and partly
filled with a liquid which is acted upon by the steam or other fluid pressure so
as to compress the air and by the level of the liquid in the cylinder or tube to
indicate the pressure on a graduated scale substantially as hereinbefore set forth.

page_text: 3. In a pressure gauge the combination of closed lower cylinder A' adapted to
be partly filled by a liquid under 1 essure through an inlet at the bottom, the
graduated closed top glass air tube A connected to the top of the cylinder A',
and the rod J floating on the liquid in the lower cylinder A¹ and free to move up
and down in the glass tube A so that as the air in the cylinder A¹ and tube A is
compressed and the liquid rises the pressure will be indicated by the position of the
top of the floating rod relatively to the graduated scale, substantially as herein before
described and illustrated by Fig. 3 of the accompanying drawings.
4. In a pressure gauge, the combination of closed cylinder A' adapted to be
partly filled by liquid under pressure through an inlet at the bottom, and the
graduated glass air tube A connected at top and bottom to the cylinder A¹, so that
as the air in the said cylinder and tube A is compressed by the rising of the
liquid the level of the liquid will indicate the pressure on the graduated scale,
substantially as hereinbefore described and illustrated by Fig. 4 of the accompanying
drawings.
5. The herein described improved pressure gauge consisting of a hollow inverted
closed top graduated glass cone A' containing air and fixed steam tight on a base A'
in which is an inlet for liquid under pressure so that as the liquid rises in the cone
and compresses the air therein the level of the liquid will indicate the pressure,
substantially as herein before described and illustrated by Fig. 5 of the accompanying
drawings.
6. The combination and arrangement of parts constituting the improved pressure
gauge hereinbefore described and illustrated by Fig. 6 of the accompanying
drawings.
7. The improved pressure gauge hereinbefore described and illustrated by
Fig. 7 of the accompanying drawings.
Deted this 20th day of October 1891
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.