or Indicators for Domestic and Telegraphic Purposes.
Year: 1885

page_text: or Indicators for Domestic and Telegraphic Purposes.
We, JAMES SHIRLEY SLEDGE of 95 Wirtemberg Street, Clapham, in the county
of Surrey, Electrical Engineer and ALFRED SLATTER of Leadenhall Chambers
St Mary Axe in the city of London, Electrical Engineer, do hereby declare the
nature of our invention for "AN IMPROVED CONSTRUCTION OF ELECTRICAL BELLS
AND ANNUNCIATORS OR INDICATORS FOR DOMESTIC AND TELEGRAPHIC PURPOSES
to be as follows:-
"
Our invention bas for its object to simplify and cheapen the construction of
electric bells and annunciators or indicators, while maintaining their efficiency.
For this purpose, we construct the electromagnet of the apparatus and the
bracket for supporting the same and the bell or annunciator of one single piece or
casting of soft iron or wrought metal, the core of the electromagnet being formed
as a reel, upon which is wound the insulated conducting wire and which has a
flange at each end constituting the poles from one side of which project two arms
or polar extensions by means of which the apparatus is fixed to its support.
To the upper polar extension is connected, by means of a spring, an armature so
arranged as to make contact with the two flanges, and, being polarised by its
connection with the one pole, its free end is brought very close to the other pole,
thus affording a very strong attraction with a small battery current.
The free end of the armature carries the striker of the bell, the latter being fitted
on a pin projecting from the second arm of the electromagnet.
In applying the above described construction of electromagnet and armature to
an annunciator or indicator, the arm carrying the disc of the latter is pivotted to
an eye on the lower pole of the electromagnet, and it has an extension-piece formed
with an elbow passing up against the outer surface of the armature, which has a
small hole into which enters a pin or stud on the said extension piece of the
annunciator when the armature is not in contact with the electromagnet, so that
the annunciator is then securely locked in the raised position.
When the armature is attracted on the passing of a current its hole ceases to be
engaged with the pin of the annunciator arm, so that this, in losing its support
will fall by its own gravity and will remain in that position until mechanically
replaced.

page_text: or Indicators for Domestic and Telegraphic Purposes.
WC, JAMES SHIRLEY SLEDGE of 95 Wirtemberg Street, Clapham in the County
of Surrey, Electrical Engineer, and ALFRED SLATTER of Leadenhall Chambers
St Mary Axe in the City of London, Electrical 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 :-
Our invention has for its object to simplify and cheapen the construction of
electric bells and annunciators or indicators, while maintaining their efficiency.
For this purpose we construct the electro-magnet of the apparatus and tho
bracket for supporting the same and the bell or annunciator of one single piece or
casting of soft iron or wrought metal, the core of the electro-magnet being formed
as a reel, upon which is wound the insulated conducting wire and which has a
flange at each end constituting the poles from one side of which project two arms
or polar extensions by means of which the apparatus is fixed to its support.
To the upper polar extension is connected, by means of a spring, an armature so
arranged as to make contact with the two flanges, and, being polarised by its
connection with the one pole, its free end is brought very close to the other pole,
thus affording a very strong attraction with a small battery current.
The free end of the armature carries the striker of the bell, the latter being
fitted on a pin projecting from the second arm of the electro-magnet.
In applying the above described construction of electro-magnet and armature to
an annunciator or indicator, the arm carrying the disc of the latter is pivotted to
an eye on the lower pole of the electro-magnet, and it has an extension piece formed
with an elbow passing up against the outer surface of the armature, which has a
small hole into which enters a pin or stud on the said extension piece of the
annunciator when the armature is not in contact with the electro-magnet, so that
the annunciator is then securely locked in the raised position.
When the armature is attracted on the passing of a current its hole ceases to be
engaged with the pin of the annunciator arm, so that this, in losing its support
will fall by its own gravity and will remain in that position until mechanically
replaced.
Figs. 1 and 2 of the accompanying drawings shew our above described invention
as applied to an electrical bell. Fig. 1 shews a front view and Fig. 2 a side view.
The core of the electro-magnet A has a flange B B' at each end, and on these flanges
are formed flat surfaces at B2, B3, constituting the poles for the attraction of the
armature C. Each flange has also formed upon it an arm D and D¹ constituting
the bracket by which the apparatus is fixed to its support. The upper arm D has
a projection D³, to which is attached the armature C by ineans of a spring E.
Thus the armature being polarised by its connection with the pole B, the electro
magnet exerts a very powerful attraction upon it, affording the same magnetic
effect as with the present double coil instruments.
The spring E has the one terminal of the wire coil attached to it at E' and it is
formed with a tail E, that makes contact with the contact pin F connected with
the one terminal G of the circuit, the other end of the coil being connected to the

page_text: other terminal G¹. On the armature being attracted by the magnet, the tail E
breaks contact with the pin F and the current being interrupted, the spring E
brings the armature back to the contact position.
The lower arm D' of the electromagnet has a projection D³ to which is attached
the bell H, and the armature C has the striker C₁ attached to it.
Figs. 3 and 4 shew respectively a front and side view of the apparatus arranged
as an annunciator or indicator. The electromagnet A and armature C are con-
structed in the same manner as before, with the exception that the lower arm D¹
of the former arrangement is in this case replaced by a lug D¹, to which is pivotted
the lever I carrying the indicator disc J.
The elbow I of the lever has a stud I2, which when the armature is in the
position shewn in full lines, not being at that time attracted by the magnet, enters
a hole in the armature when the lever is raised by the tail 13, and thus maintains
the lever and indicator in the upright position. When the armature is attracted
on the passing of a current, the stud is released therefrom, and consequently the
lever and indicator fall into the dotted position, in which they are held by the
stop K. It will be evident that the stud night be arranged on the armature, and
the hole in the lever, also, that any other form of catch may be used in lieu of
the stud and hole.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. Constructing the electro-magnet of a call bell or annunciator with a core
formed in one piece with polar extensions constituting brackets by which the
electromagnet is attached to its support, substantially as herein described.
2. In the construction of electromagnets referred to in the preceding claim,
arranging the one polar extension of the core as the means of attachment for the
armature, which makes contact with a flange-shaped pole formed on each end of
the core, and which is connected to the polar extension by a spring, substantially
as herein described.
3. The combination of the electro-magnet A having flange-shaped poles B B
formed on its core with polar extensions D D' constituting bracket for the attach-
ment of the apparatus, the one polar extension having the armature C with
striker C connected to it by a spring E, while the other polar extension carries the
bell H, substantially as herein described with reference to Figs. 1 and 2 of the
drawings.
4. In combination with an electro-magnet constructed as set forth in the first
and second claim the use of a lever carrying an annunciator disc and so arranged
to gear with the armature of the electromagnet by means of a catch, that when the
armature is not attracted it holds the lever and disc in the raised position, but
when it is attracted it releases the lever and allows it and the disc to fall, substan-
tially as herein described.
5. The combination with the electro-magnet A and armature C of the lever I
with annunciator disc J and stud I that engages with a hole in the armature C,
when this is not attracted by the electromagnet, substantially as herein described
with reference to Figs. 3 and 4 of the drawings.