An Improved Electric Alarm for Varying Levels and Pressures.
Year: 1888

page_text: Date of Application, 27th July, 1888
Complete Specification Left, 5th Apr., 1889-Accepted, 20th July, 1889
PROVISIONAL SPECIFICATION.
An Improved Electric Alarm for Varying Levels and Pressures.
I, ANDREW SIEGMANN of 296 Portobello Road Notting Hill, in the county of
Middlesex, Builder, do hereby declare the nature of this invention to be as
follows:-
•
In the specification of my invention No. 13974 dated 14th October 1887, I have
described an eletrical means of approximately indicating the water level or steam
pressure in a boiler or other analogous vessel on approaching the danger point;
and for indicating levels generally.
Now, in accordance with my present invention instead of the system of adjustable
spring contacts, the free ends of which obtrude into the path of the index, as set forth
in the Specification of my invention of prior date hereto, I employ the following
simple, efficient and inexpensive means of attaining the same object. Upon the dial
plate of a Bourdon or other steam or water guage, at a suitable part thereof, is formed
a slot or aperture of convenient size, closed at the back by a plate of some suitable
insulating or nonconducting material, upon which is mounted a thin flat metal plate of
nonoxidisable metal, preferably platinum, or of other metal tipped with platinum,
secured at one or both ends, and so arranged as to project beyond the surface of the
dial plate aforesaid. Upon the top or other convenient part of the case of the guage
are mounted upon a plate of insulating material, and secured thereto, two binding
screws, one of which is in electrical connection with the dial plate and index
pointer, and the other is in electrical connection with the nonoxidisable plate above
referred to.
An electric bell and galvanic battery are provided, one pole of the latter being
connected with one side of the electric bell, and the other pole with one of the binding
screws upon
the guage aforesaid; the second binding screw is connected with the other
side of the electric bell.
As the level of the water rises, or the pressure of the steam increases, the index
pointer, in its movement over the dial plate, comes in contact with the nonoxidisable
metal plate aforesaid, closes the electrical circuit, causing the electric bell to ring, and
thus announcing the existence of danger.
From the foregoging it will be obvious that the device herein described according
to my invention, is not confined to water or steam guages, but is applicable to other
guages and indicators in which the index pointer moves upon a centre.
Dated this Thin
1
ст 1
1000
JAMES STEVENSON,
Gray's Inn Chambers, 20, High Holborn, London, W.C., Agent for Applicant.
COMPLETE SPECIFICATION.
An Improved Electric Alarm for Varying Levels and Pressures.
I, ANDREW SIEGMANN of 296 Portobello Road, Notting Hill, in the County of
Middlesex, Builder, 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 :-
In the specification of my Invention No. 13974 dated 14th October 1887, I have
described an electrical means of approximately indicating the water level or steam
pressure in a boiler or other analogous vessel on approaching the danger point, and
for indicating levels generally.
Now, in accordance with my present Invention instead of the system of adjustable

page_text: spring contacts the free ends of which obtrude into the path of the index as set forth
in the specification of my Invention of prior date hereto, I adopt a method which is
not only inexpensive but simple in construction and efficient in working.
In order that my Invention may be the better understood I have appended the
accompanying sheet of drawings in which Figure 1 is a front elevational view of a
manometer to the dial plate of which is adapted iny improved appliance; Figure 2 is
a back view, and Figure 3 is an end view of said dial plate and appliance. Figuro 4
shows an alternative method of closing the electrical circuit.
Upon the dial plate of a Bourdon or other manometer A, Figure 1 and at a suitable
part thereof is formed a slot or aperture or slots or apertures a of convenient size,
closed at the back by a plate B, Figures 2 and 3 of some suitable insulating or
nonconducting material upon which latter is mounted one or more thin flat metal
plates C of nonoxidisable metal-preferably platinum-or of other metal tipped or
plated with platinum, secured at one or both ends as shown, and so arranged as to
project slightly beyond the surface of the dial plate A aforesaid.
Upon the top, or other convenient part of the case of the manometer or pressure
gauge, are two binding or connecting screws b, b¹ which may be mounted either
upon a plate of insulating material, or, if desired, the ends thereof may be passedl
through insulating rings or sleeves inserted in and secured to said case. One of said
binding screws b is in electrical connection with the index pointer D of the gauge, and the
other binding screw 6¹ is in electrical connection with the nonoxidisable metal plate C
above referred to. An electric bell and galvanic or voltaic battery are provided, one pole of
the latter being connected with one side of the electrical bell, and the other pole of the
battery with, say, the binding screw 6 upon the case of the gauge; the binding screw 61
being connected with the other side of the bell above mentioned.
In using the apparatus above described, assuming that it is desired to have notice
of the rise of water or pressure of steam to a definite height, say between 90° and 100°,-
one of a number of screws c Figures 2 and 3 with which the apparatus is provided is
caused to press the metal plate ♂ outwards as shown at e' Figure 3, sufficiently to allow
of the index pointer D making contact therewith in its travel over the dial A aforesaid,
thus closing the electrical circuit and causing the bell to ring, thereby announcing that
the desired pressure of steam or height of the fluid has been obtained.
I may however under some circumstances dispense with the thin metal plate Cabove
described and close the electrical circuit by causing the index pointer D to make
contact direct with the screws c, under which latter arrangement I may employ a
number of screws & Figure 4 passing through a metal plate e secured to the back of
an insulating plate f.-The number of screws d would preferably correspond with
each 10° marked upon the dial A ; and, upon the inner side of the index pointer D.I
may attach a thin pliable plate of metal-preferably platinum-so bent or shaped as to
ensure a perfect electrical contact without undue pressure.
It will be seen that I am enabled by means of the arrangement above described to
ensure the automatic notification of the increase of pressure, or rise of fluid to any
desired degree; and, it is further obvious that the herein described device according
to my present Invention is not confined to water or steam gauges alone, but is
applicable to other gauges and indicators in which the index-pointer moves upon
a central axis.
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 1
claim is :-
The improved electric alarm for varying levels and pressures wherein an electric
circuit is caused to be closed at any desired point substantially as herein described and
illustrated in the accompanying drawings.