AN IMPROVED ANNUNCIATOR OR INDICATOR DROP FOR TELEPHONE EXCHANGES AND THE LIKE."
Year: 1882

page_text: LETTERS PATENT to Magnus Volk of Brighton, in the County of Sussex,
Electrician for an Invention of "AN IMPROVED ANNUNCIATOR OR INDICATOR
DROP FOR TELEPHONE EXCHANGES AND THE LIKE."
PROVISIONAL SPECIFICATION left by the said Magnus Volk at the Office
of the Commissioners of Patents on the 23rd February 1882.
MAGNUS VOLK, of Brighton, in the County of Sussex, Electrician.
"AN
IMPROVED ANNUNCIATOR OR INDICATOR DROP FOR TELEPHONE EXCHANGES AND
THE LIKE"
This invention relates to the construction of an improved annunciator_or
indicator drop for telephone exchanges and the like the object of the invention
being to obtain great compactness with simplicity of construction and certainty
of action.
In carrying out my Invention I employ a suitable frame provided with an
electro magnet and baving a vertical armature on the top of which rests the
indicator drop so arranged as to fall into a vertical position when the armature is
attracted to the electro magnet. The drop is recessed to admit of receiving the
indicating card; on the back of the frame I provide a pair of insulated studs to
which the ends of the coil wires of the electro magnet are connected; for each pair
of studs a corresponding pair of terminal studs is provided in the back of the
indicator case.
By this construction of annunciator or indicator drop the electrical connections
are made by simply screwing it up into its place whereby the hereinbefore
described insulated studs will come into contact with the said terminal studs no
connecting wires being required between the terminal wires and the coils.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Magnus Volk in the Great Seal Patent Office on the 23rd August
1882.
" AN
IMPROVED ANNUNCIATOR OR INDICATOR DROP FOR TELEPHONE EXCHANGES AND
THE LIKE"
MAGNUS VOLK, of Brighton, in the County of Sussex, Electrician.
This invention relates to the construction of an improved annunciator or
indicator drop for telephone exchanges and the like the object of the invention
being to obtain great compactness with simplicity of construction and certainty of
action.
In carrying out my invention I employ a suitable frame provided with an
electro-magnet and having an armature on which rests the indicator drop so
arranged as to fall into a vertical or horizontal position when the armature is
attracted to the electro-magnet. The drop is recessed to admit of receiving the
indicating card; on the back of the frame I provide a pair of insulated studs or
bolts to which the ends of the coil wires of the electro-magnet are connected; for
each pair of studs a corresponding pair of terminal studs is provided in the back
of the indicator case.
By this construction of annunciator or indicator drop the electrical connections
are made by simply screwing it up into its place whereby the herein before
described insulated studs will come into contact with the said terminal studs no
connecting wires being required between the terminal wires and the coils.
In order to enable my invention to be better understood I will proceed to
describe the same by reference to the accompanying drawing in which figure 1, is
a front view and figure 2, a side view of an annunciator or indicator drop for
telephone exchanges constructed according to my invention; figure 3. is a vortical
transverse section of the same and figure 4, is a section on the line a, b, of figure 3.
Similar letters in all the figures represent similar parts:—
A, is the frame; B, the armature; C, the coils of the electro magnet; D, the
drop; E, the indicating card or number holder; F, the insulated terminal studs or
bolts; G, H, terminal stud nuts at the back of the indicator frame; I, insulators
for terminal studs F; J, pins for contact between the bolts or terminal studs F.
and coil wires C; K, poles of electro magnet.
The improved annunciator is attached to the case in the following manner, two
holes are bored in the indicator frame L, to receive the terminal bolts or studs F, F,
which are pushed through the said holes, the fastening nuts G, are then screwed
on and lastly the nuts or terminals H, H, under which the line wires are placed.
The terminal bolts or studs F, F, and pins J, J, are insulated from the frame A, by
the insulating studs I, I.
The ends of the coil wires are soldered to the pins J, J.
The action of the apparatus is as follows:-the current entering by one of the
terminal bolts F, traverses the coils C, C, and leaves by the other terminal bolt F,;
the passage of the current magnetises the poles K, K, which attract the armature B,
thus releasing the drop D, which falls either into a horizontal or vertical position,
according to the position of the stop M, placed underneath, thus exposing the
number placed in the holder E. The drop D, is replaced in its normal position by
hand.
Having thus described my Invention and the manner of performing the same I
wish it to be understood that what I claim is :-
Firstly. The improved annunciator or indicator drop for telephone exchanges

page_text: and the like arranged and operating substantially as hereinbefore described and
represented in the accompanying drawing.
Secondly. The method herein described of attaching annunciators or drops to
indicators by the employment of insulated terminal studs on the frame of the
annunciator in combination with terminal studs in connection with the line wires
substantially in the manner and for the purposes herein-before described and
represented in the accompanying drawing..
In witness whereof I the said Magnus Volk have hereto set my hand and
seal this Twenty second day of August in the year of our Lord One
thousand eight hundred and eighty two.
TEATT
MAGNUS VOLK. (L.D.)