An Improved Electric Alarm for Varying Levels and Pressures.
Year: 1887

page_text: GUMI LEID STEVITICATION.
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, as the same has
been communicated to me from abroad by Charles Marohn, of Schwetz, Germany, and
in what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:
--
This invention relates to an improved electrical alarm especially adapted for
indicating the approximation of the water level, or steam pressure, in a boiler, or other
analogous vessel, to danger-point; and consists in the combination, with an electric
bell system and the index of a dial-gauge, of a system of adjustable spring contacts
the free ends of which obtrude into the path of the index at the limits thereof, whereby
the presence of the index at either limit is instantaneously signalled.
In order that this invention and the means by which the same is to be carried into
practical effect, may be thoroughly understood, I will proceed to describe the same in
detail, referring in so doing to the accompanying drawings which are to be taken as
part of this specification and read therewith."
Fig. 1 is a front elevation.
Fig. 2 is a transverse sectional elevation.
Fig. 3 is a front elevation after removal of the cover.
Fig. 4 is an elevation of the back of the cover with the intermediate spring
contacts.
Fig. 5 is a sectional elevation corresponding therewith.
Fig. 6 is a front elevation of the cover, and
Fig. 7 is a front elevation, on a reduced scale, illustrating the application of this
invention to the water gauge of a vertical steam boiler; and
Figs. 8 and 9, are, respectively, rear elevation and plan corresponding therewith.
A is the case; a, its cover held in position by a screw, b, passing through the
block B into the back; and C, a tube adapted to receive the leads c, c, and prevent
their being injured.
B is a block of insulating material upon which some of the parts of the invention.
are fixed.

page_text: E is a plate spring centrally held to the cover, a, in any convenient way, its
arms e, e¹, standing out from the cover, and obtruding into the path of the index, F.
Behind the cover, a, I fix upon it and in line, two metallic spring bars ff, held to
the cover by means of set-screws passing through slots g, g¹, formed in the bars for
the purpose of adjusting their position relatively to the arms e, e¹. Each spring bar
is provided with a stud 1, h', projecting through a slot i, i, formed for that purpose in
the cover, a. Springs or intermediate contacts j, j, are fixed upon the back of the
bars ff, respectively and are adapted to maintain contact with springs k, k', fixed
upon the block B by screws d, d. Underneath the free ends of the springs k¹, k¹,
and normally out of touch with them, are fixed the contact screws 1, 1. The lead, c,
is bifurcated and connected to the contact screw, !, and also to the screw,
d'; while
the lead, c¹, is connected to the contact screw, l', and the screw, d.
The leads connected as above described and carefully insulated are led away through
the tube C to the battery and alarm.
The arms e, e', project through holes cut for that purpose in the dial, P, of the
gauge; and consequently obtrude into the path of the index, F, as already explained.
Qis the float connected to the index so that its motion either up or down shall be
communicated to the index F.
The action of my invention is as follows.
The studs, h and h¹, are first adjusted with reference to the arms e, e¹, of the
spring E, so that the movement of the index, F, on either side of the centre of said
spring without depressing said arms upon the studs h, h, shall be limited within two
extremes.
The rise of the water in the boiler will carry the float up with it, and at last make
the index depress the arm, e, upon the stud, h. The spring bar, f, will be pressed
backwards, and the spring, j, force the spring, k, upon the contact screw, l, when the
electric circuit will be closed, and the alarm sounded.
The descent of the float beyond a certain level will, likewise, cause the index, F, to
press upon the arm, e¹, and consequently close the electric circuit at l.
It is self-evident that the application of this invention is not limited to water or
steam gauges; but is applicable to all dial gauges whether used for indicating the
changing levels of liquids, pressures of vapours, or any other analogous variation.
Having now particularly described and ascertained the nature of my said invention'
and in what manner the same is to be performed, as the same has been communicated
to me from abroad, I declare that what I claim is :-
In an electric alarm adapted to be combined with a dial-and-index gauge, the
combination of two spring-ends obtruding into the path of the index, and adapted to
be pressed back by said index at the respective ends of its determined path, with spring
plates carrying springs or intermediate contacts on them adapted to establish contact
with springs forming parts of an electric circuit and which are adapted to respectively
close said circuit by contacting with respective contact screws in said circuit under
the pressure transmitted from the index, substantially as described with reference to
the accompanying drawings.