An Improved Electric Pressure Indicator.
Year: 1890

page_text: Date of Application, 11th Nov., 1890
Complete Specification Left, 11th Sept., 1891-Accepted, 17th Oct., 1891
PROVISIONAL SPECIFICATION.
An Improved Electric Pressure Indicator.
1 CHARLES HODGKINSON GRAY of Frankfort-on-Maine in the Empire of
Germany Engineer do hereby declare the nature of my invention for AN
IMPROVED ELECTRIC PRESSURE INDICATOR to be as follows:-
This invention has for its object an improved electric pressure indicator whereby
a simple and inexpensive instrument is constructed. The said instrument being so
arranged that immediate warning is to the attendants in charge of such places as
gas works &c. gas steam air or other engines. So soon as the pressure becomes
too high or too low in the gas mains or in the cylinders of engines or other
appliances a bell or other alarum is electrically rung. The invention consists of
constructing in any desired shape design or material a watertight cylindrical
chamber open at its upper end and fitted to a suitable base plate; this chamber is
provided with a steam gas or air inlet pipe which passes vertically through the base
plate and to a point near the top of the said chamber. A cock or tap is provided
at the lower part thereof to draw off the water in said chamber when desired and
near the upper part of the chamber another cock or tap is provided for an over-
flow or to regulate the water supply therein. Inside the cylindrical chamber above
referred to secure centrally a vertical spindle upon which a float or hollow
cylinder rises or falls according to pressure. It has its ends closed or sealed and
has another cylindrical chamber surrounding it and having its upper end closed
and lower end open. These cylindrical chambers are secured together by suitable
stays which also act as guides therefor. The chamber enclosing the float has
secured to its upper outer end a short spindle upon which a horizontal arm or
projection is adjustably secured the said arm having a platinum or other metallic
prolongation. Away from the outside of the cylindrical chamber above described
a hollow vertical standard or column is suitably secured to the base plate, in which
a spindle works vertically having a groove or feather in one side thereof to prevent
it turning or an adjusting pin or set screw may be employed to keep said spindle
in its proper working position. Adjustably attached to the spindle is a horizontal
arm of sufficient length to overlap the arm or projection fixed to the upper outer
end of the floating chambers and above this arm and either adjustable or not as
desired is another horizontal arm of the same length both these arms are provided
with a platinum or other metallic projection or elongation.
To the lower end of the hollow vertical shaft or column above described an
electric terininal is fixed. Another terminal being secured to the vertical spindle
upon which the floating chambers or cylinders work. These terminals are
connected in any suitable known manner to an electric bell or other alarum and to
battery of ordinary description.
In some cases I provide a suitable gauge glass so as to show at a glance the
xact degree or amount of pressure on the gas mains, or other appliances working
nder pressure.
The operation of the invention is as follows:
The outer cylindrical chamber is supplied with water of sufficient quantity to
each the water line cock or tap; the cylindrical chambers then float and so soon
s the gas, air, steam, or other pressure enters through the inlet pipe or tube it
auses the cylindrical chambers to rise or float and should the pressure be too high
he horizontal arm or projection on the spindle secured thereto will come in contact
ith the upper horizontal arm on the spindle in the hollow vertical column closing
e electric circuit and thus ringing the bell or alarum.
Should the pressure be too low the horizontal arm on the spindle secured to the

page_text: cylindrical chambers will fall and come in contact with the lower horizontal arm
adjustably secured to the sliding spindle working in the hollow column and thus
making contact and giving the alarum.
Dated this 11th dov of November 1890.
CHARLES H. GRAY.
COMPLETE SPECIFICATION.
An Improved Electric Pressure Indicator.
I CHARLES HODGKINSON GRAY of Frankfort on Maine Germany do hereby
declare the nature of the said 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 for its object an improved electric pressure indicator whereby
a simple and inexpensive instrument is constructed. The said instrument being so
arranged that immediate warning is given to the attendants in charge of such
places as gas works &c. or in attendance on gas steam air and other engines.
So soon as the pressure becomes too high or too low in the gas mains &c. or in
the cylinders of engines or other motors or apparatus a bell or other alarum is
electrically rung.
The invention consists of constructing in any desired shape design or material a
watertight cylindrical chamber or tank open at its upper end and fitted to a
suitable base plate; this chamber is provided with a steam gas or air inlet pipe
which passes vertically through the base plate and to a point near the top of the
said chamber.
Inside the cylindrical chamber above referred to I secure a vertical spindle upon
which a float or hollow cylinder rises and falls according to the pressure brought
thereon. It has its ends closed or sealed and has another cylindrical chamber
surrounding it having its upper end closed and lower end open. These cylindrical
chambers are secured together by suitable stays which also act as guides therefor.
The chamber enclosing the float has secured to its upper outer end a short spindle
upon which a horizontal arm or projection is adjustably secured, the said arm
having a platinum or other metallic prolongation.
Away from the outside of the cylindrical chambers above referred to, a hollow
vertical standard or column, is suitably secured to the base plate and insulated
from the tank containing the float in which a spindle works vertically having a
groove or feather in one side thereof to prevent its turning or an adjusting pin or
set screw may be employed to keep said spindle in its proper working position.
Adjustably attached to the spindle is a horizontal arm of sufficient length to
overlap the arm or projection fixed to the upper outer end of the floating chambers
and above this arm and either adjustable or not as desired is another horizontal
arm of the same length both these arms are provided with a platinum or other
metallic projection or elongation.
To the lower end of the hollow vertical shaft or column above described an
electrical terminal is fixed. Another terminal being secured to the vertical spindle
upon which the floating chambers or cylinders work. These terminals are connected
in any suitable known manner to an electric bell or alarm and to a battery of
ordinary description.
In order that my invention may be properly understood and readily carried into
effect I will now describe the same more fully aided by the accompanying drawing
which represents partly in section and partly in elevation an electric pressure
indicator constructed according to my invention.
A watertight chamber or vessel « open at its upper end is fitted to a base plate b
passing through said base plate 6 & extending vertically to near the upper part of
the cylinder a & above the water line is a steam gas or hot air inlet pipe c.
Secured to the base plate band passing centrally through the chamber or

page_text: cylinder a is a spindle d which serves as a guide to the float e secured to the
or closed end of the chamber f. Said float e is further kept in its proper working
upper
position by means of stay e¹ fixed to the inner sides of the chamber or vesself and
to the outer sides of the float e.
The float e and chamber fare thus formed in one with each other and rise and
fall on the spindle d as hereinafter more fully described.
To the upper or closed end of the chamber fis attached a short spindle f¹ to
which is adjustably secured a horizontal arm or projection f' having a platinum
extension piece f³.
The chamber a is provided with an outlet cock or tap a¹ and an inlet cock or
tap a such cocks or taps regulating the water supply therein.
To the base plate b or other convenient part of the apparatus and insulated from
the tank is secured a hollow vertical standard or column g in which the spindle h
works, said spindle being adjusted by the set screw g¹. Attached to the spindle h
is a horizontal arm having a platinum or other metallic extension contact
piece attached thereto, said arm being adjusted by the set screw h³ and is of
sufficient length to overlap the extension piece f³ attached to the arm f
Above the horizontal arm and secured to the spindle is another horizontal
arm having a platinum extension piece which also overlaps the horizontal
armf such arm being adjustable or not as desired.
To the lower end of the column or standard is secured an electric terminal j
and a like terminal d is secured to the spindle d.
Said terminals are connected to a battery and alarum in the well known
manner.
The operation of the invention is as follows:-
:-
The cylindrical chamber a is supplied with water sufficient to reach the cock or
tap a² the float e and chamber would then rise a certain distance on the spindle d
where it would remain balanced as it were until the gas, air, steam or other
pressure, enters the pipe e and passes into the upper part of the chamber forcing
said chamber and float e in an upward direction when should the pressure of gas
on the mains, or the pressure on the cylinder of an engine or other motor be too
great the platinum extension piece 3 on the horizontal arm f' would come in
contact with the platinum extension piece on the horizontal arm ³ secured to
the spindle thus closing the electric circuit and ringing the bell or alarum which
may be situated in any desired part of the works.
And likewise should the pressure be too low the platinum extension piece³
would come in contact with the extension piece h² close the circuit and sound the
larum.
If desired a gauge may be fitted to the apparatus to show at a glance the exact
legree or amount of pressure therein.
On the inside of tank and on the float is or are affixed pieces of platinum to
ensure a more perfect electrical contact.
Having now 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
The general construction and arrangement of parts constituting an electric
ressure indicator substantially as herein described and shown in the accompanying
rawings and for the purpose stated.
Dated this Eleventh day of September 1891.
CHARLES H. GRAY.