Improvements in and connected with Electric Bells.
Year: 1894

page_text: Date of Application, 17th Feb., 1894.
Complete Specification Left, 17th Nov., 1894-Accepted, 22nd Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in and connected with Electric Bells.
I, HOWARD BLAIN LITTLE, of 20 Eldon Road, Kensington in the County of
Middlesex, Electrical Instrument Maker, do hereby declare the nature of the
said invention to be as follows:-
The first part of this invention relates to improvements in the mechanism
employed for actuating electric bells generally and the second part thereof relates
to what are known as portable or invalid electric bell sets.
According to the first part of this invention I employ an electro-magnet which
consists of a single coil, in place of a double one as heretofore commonly employed
and having the usual core passing through the same, the ends of such core being
so arranged as to form pole pieces the acting surfaces of which are so disposed in
relation to the armature that the latter is attracted by both of such surfaces. For
example, the ends of the core may be provided with separate pole pieces which
project at right angles to the axis of the coil, their acting surfaces being in a plane
parallel to such axis. The armature is so mounted as to be free to vibrate in a plane
at right angles to the axis of the coil, and I prefer to effect this by interposing a
thin brass or other strip between the said armature and its point of support, which
latter may be one of the beforementioned pole pieces, or any other convenient part
of the apparatus. This thin brass or other strip is preferably bent into a long U.
or other convenient shape which shall facilitate the perfect freedom of movement
of the armature in the desired direction.
According to the second part of this invention instead of winding the conducting
wires which connect the bell and battery to the push or other contact maker, in a
coil or over hooks or cleats on the battery box as heretofore, I provide a bobbin
or roller preferably mounted on some convenient part of the apparatus, and capable
of containing the necessary quantity of wire. This bobbin or roller is adapted to
be turned by means of a winch handle or other similar device, and the necessary
connections between the wires and the apparatus may be made by means of a
divided axis, or by contact plates or brushes on the side or other convenient part
of the bobbin in a manner well understood in connection with this class of work.
Or in some cases I employ a spring actuated bobbin, the said spring being wound
up by the act of drawing off the conducting wires and automatically winding up
the said wires, as it is allowed to run down, the action being somewhat similar to
that of the well known form of spring measuring tapes.
Dated this 17th day of February 1894.
H. B. LITTLE,
Per W. H. Beck,
115, Cannon Street, London, Agent.

page_text: Improvements in and connected with Electric Bells.
I, HOWARD BLain Little, of 20 Eldon Road, Kensington, in the County of
Middlesex, Electrical Instrument Maker, 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, that is to say :-
The first part of this invention relates to improvements in the mechanism
employed for actuating electric bells generally, and the second part, to what are
known as portable or invalid electric bell sets.
And in order that the said invention may be fully understood I will now
proceed to describe the same with the aid of the accompanying sheet of drawings,
in which Figure 1 is a front elevation of a bell set constructed in accordance with
the invention, and Figure 2 a side view of same.
According to the first part of this invention I employ an electro-magnet which
consists of a single coil A in place of a double one as heretofore commonly
employed. This coil A has a soft iron core passing through it as usual, the ends
of which are provided with pole pieces the acting surfaces of which are so disposed
in relation to the armature that the latter is attracted by both of such surfaces.
For example the ends of the core may be provided with separate soft iron pole
pieces B, B, which project at right angles to the axis of the coil A, their acting
surfaces B B' being in a plane more or less parallel to such axis.
The
armature C is so mounted that it is free to vibrate towards and away from the
axis of the coil. I prefer to effect this by interposing a thin brass or other
suitable strip or spring D. between the said armature and its point of support,
which latter may be. one of the before mentioned pole pieces B, (as shown in
Figure. 1) or any other convenient part of the apparatus. This thin strip or
spring D is preferably bent into the shape of a long U whereby much greater
freedom of movement of the armature in the desired directions is obtained than by
the straight strip or spring usually employed.
E is a terminal connected to one pole of the battery, not shown in the drawings
but which may be contained in the box F. A wire G connects the terminal E
with one end of the coil A; the other end of this coil is connected by the wire H
to the strip or spring D, a prolongation of which forms the make and break
spring I.
K is a post provided with an adjusting screw L against the end of
which the make, and break spring I bears when the bell is not in use. M is a wire
connecting the post K with the terminal N; and this latter is connected with one
of the wires P leading to an ordinary push or other contact-making appliance O at
the hand of the person using the bell, the other wire from which push or contact
maker goes to the other pole of the battery, so that when the electric circuit is
closed by the said push or contact maker the current passes from the battery to E,
thence by G, A, H, D, I, L, K, M, N and P to the push or contact maker and
thence back to the battery. The passage of the current excites the electro-
magnet and the armature C is attracted by both pole pieces B B, causing the
hammer Qto strike the bell R, at same time withdrawing the spring I from the
end of the screw L, thereby breaking the circuit and the armature then falls back
so that the spring I re-establishes the circuit in the ordinary well known way.
The above described method of mounting the armature by means of a strip or
spring of shape may be applied with advantage to electro-magnets of other
forms besides that shown in Figure 1, as for example to a horse-shoe electro-
magnet as shown in Figure 3.
The electromagnet and armature may be covered by a box S to preserve them
from injury, dust & dirt.

page_text: By the arrangements above described electric bells can be worked with less
power than beretofore, their construction is simplified and the cost of production
and the size of the apparatus are materially reduced.
According to the second part of the invention, instead of winding the conducting
wires which connect the bell and battery to the push or other contact maker, in
a coil or over hooks or cleats on the battery box as heretofore, I provide a bobbin
or roller T, preferably mounted on some convenient part of the apparatus, such as
the box F for example and capable of containing the necessary quantity of wire.
This bobbin or roller T turns on a fixed stud U, and can be rotated by a winch
handle V or otherwise; and the necessary connections between the wires and the
bell on the one hand, and the battery on the other, may be made by any suitable
means as for example by that shown in the drawings in which W and X are two
segmental plates fixed to the side of the box F. One of these plates is electrically
connected with the battery by means of a wire not shown in the drawings, and the
other with the electro-magnet A of the bell through the wire P and terminal N.
Plates Y Y of insulating material may be interposed between the ends of the
plates W X. Z Z' are studs or brushes fixed to the end of the bobbin or roller T
and adapted to bear against the plates W X. Z is one of the conducting wires
connected to the stud or brush Z, and Z is the other conducting wire connected
to the stud or brush Z'. The two conducting wires Z Z₁ are preferably twisted
together into the form of a cord in the usual manner and are connected to the
push O or other contact maker in the usual way. It will now be understood that
by turning the bobbin T on its stud by the handle V the conducting wires can be
wound on to the same or unwound therefrom as may be required; care being taken
that when the bell is to be used the bobbin T must be stopped in such position
that the stud or brush Z bears against one of the plates W or X and the stud or
brush against the other of such plates. The studs or brushes Z Z' are
preferably so mounted on the bobbin T that they are pressed by springs or
otherwise constantly against the plates W X notwithstanding any irregularity in
the motion or position of the said bobbin relatively to the said plates.
If desired the bobbin or roller T may be actuated by a spring which is wound
up by the act of drawing off the conducting wires; and acts automatically to wind
up such wires as it runs down, the action being similar to that of the well known
spring measuring tape, or spring roller for blinds.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
First. In electric bell mechanism the use of an electro-magnet having a pole
piece at each end the acting surfaces of which are in a plane more or less parallel
to the axis of the electro-magnet, substantially as described.
Second. In electric bell mechanism, mounting the armature of the electro-
magnet on a shaped strip or spring, substantially as described.
Third. In an electric bell set the of a bobbin or roller for winding-on the
conducting wires, such bobbin or roller being provided with means for maintaining
electric connection between the said conducting wires and the battery and the
electro-magnet of the bell mechanism, substantially as described.
Dated this 17th day of November 1894.
Dated this 17th day of November 1094.
H. B. LITTLE,
Per W. H. Beck,
115, Cannon Street, London, Agent.