AN IMPROVEMENT IN ELECTRICAL SIGNAL OR CALL BELLS
Year: 1884

page_text: I, JOSEPH DEVONPORT FINNEY ANDREWS of Woodside Electric Works, Woodside
Road, Glasgow, North Britain, Electrical Engineer, do hereby declare the nature of
my said invention for "AN IMPROVEMENT IN ELECTRICAL SIGNAL OR CALL BELLS'
to be as follows:-
"
My invention relates to electrical signal or call bells such as are used for
telegraphic and telephonic communication, the objects which I have in view being
simplicity and cheapness of construction. For this purpose, I attach the ball striker.
of the bell by an elastic wire to a stem of iron which lies as an armature between
the poles of the electromagnet and which terminates at its end in a knife edge that
enters a notch in a piece of iron or steel attached to the permanent magnet which
forms the polar field of the magneto-machine employed for sending a bell current
to a distant station. The stem of the striker which is magnetised by induction
from the permanent magnet is caused to vibrate when alternating currents pass
through the coils of the electro-magnet, and the ball striker, being thus made to
oscillate between two bells, causes them to sound. By thus utilising the permanent
magnet of the magneto-machine, the magnet usually employed to polarise the bell
armature is dispensed with.
ABEL & IMRAY,
Agents for the Applicant,
28, Southampton Buildings,
London, W.C.

page_text: I, JOSEPH DEVONPORT FINNEY ANDREWS, of Woodside Electric Works, Woodside
Road, Glasgow, North Britain, Electrical Engineer, do hereby declare the nature of
my invention for "AN IMPROVEMENT IN ELECTRICAL SIGNAL OR CALL BELLS" and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
My invention relatos to electrical signal or call bells such as are used for
telegraphic or telephonic communication, the objects which I have in view being
simplicity and cheapness of construction, as I will describe referring to the
accompanying drawings.
Fig. 1 is a front view with the front cover removed to shew the interior, and
Fig. 2 is a vertical section of call bell apparatus to which my invention is applied.
A A are two permanent magnets of horse shoe form between the poles of which
the armature B is caused to revolve by means of a band, pulley and handle O in
the usual way, thus generating the electric currents which work the call bell or
signal at a distant station. On a bracket D of iron or steel firmly fixed to the
magnets AI pivot the iron or steel bar E which is free to vibrate between the
poles of the electro-magnets F F and which carries at its end the ball striker G that
oscillates between the bells H H. The bar E is polarised by induction from the
magnets AA and consequently, whon the electro-magnets F F are excited by
alternating currents from a distant station, E is caused to vibrate and the bells H
are sounded,
By thus utilising the permanent magnets A of the magneto-munchine employed to
actuate the signal at a distance, the inagnet usually employed to polarise the bell
armature is dispensed with.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
] claim is
In electrical signal or call bell apparatus, polarising the bell arinature by induction
from the magnet of the magneto-machine employed to netuate a distant signal,
substantially as and for the purpose herein set forth.
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