Improvements in Magneto Generators and Telephones to be Used in Connection therewith.
Year: 1889

page_text: Date of Application, 27th Mar., 1889-Accepted, 21st Sept., 1889
COMPLETE
SPECIFICATION.
Improvements in Magneto Generators and Telephones to be Used in
Connection therewith.
A communication from abroad by General ELIAS M. GREENE, of the City of New York,
in the United States of America.
I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents 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 :-
This Invention relates principally to magneto machines for telephoning and signalling,
and in such it has for its object to produce a simple and complete magneto generator
adapted to send comparatively weak currents for the purpose of operating signal
bells and the like, and to utilise said generator as a part of a magneto telephone; and
to these ends the invention consists in the various constructions and arrangements
substantially as hereinafter set forth.
-
In the accompanying drawings which form part of this Specification
Fig. 1 is a side view illustrating one embodiment of the invention.
Fig. 2 is a similar view illustrating another form.
Fig. 3 illustrates an annular magnet.
Figs. 4 and 5 are respectively plan and side views of another embodiment of the
invention.
Figs. 6 and 7 are side views illustrating other forms.
Fig. 8 is a sectional view illustrating the preferred form of telephone, and
Fig. 9 is a plan of the preferred form of diaphragm.
In the construction of magneto telephones it is a great desideratum to have a strong
magnetic field in which the diaphragm shall be placed, so that slight variations or
movements in the diaphragm will cause correspondingly large impulses or changes
of potential on the line, and, on the contrary, the changes of potential on the line
will cause correspondingly large variations in the diaphragms of the receiving
instruinents. It has been usual to connect with the telephone line magneto signalling
apparatus by means of which the attention of the subscribers or operators can be
called. In this invention the same magnet is utilized for the purpose of furnishing
the strong magnetic field for the telephone and for producing the magneto currents
for operating the bell. This general idea may be carried out in many and various
ways, some of which are illustrated herein.
Referring more especially to Fig. 1 of the accompanying drawings, 1, 2 and 3 are
circular, ring-shaped permanent magnets forming a compound magnet having a cut
away portion at the point 4. While the compound magnet is shown as composed
of three permanent magnets, of course it may be composed of more or less.
Embracing this compound magnet are the permanent magnets 5, 6, 7, 8, which are
arranged to surround the compound magnet to a certain extent, and their ends 9, 10,
are extended outward, as shown, and preferably support soft iron cores 11, 12, each
of which is surrounded by a main coil 13, 14, and in front of these coils are sup-
ported the diaphragins 15 of the transmitting and receiving telephones T, R.
Suitably mounted within the compound magnet is an armature 16, having coils 17,
connected in the main line, and this armature is adapted to be rotated by any
suitable means, as by the cog wheels 18, 19, the latter of which is provided with a
suitable handle 20. Arranged in the circuit is a magneto bell 21 for sending and
receiving signals.
While in this instance the bell and armature of the generator are shewn as being
directly in the main line circuit, it is evident that they may be arranged in the
usual manner, so that they will be cut out of circuit when the telephones are in
use, and the telephones will be cut out of circuit when the bells are in use.
"
Price &dl

page_text: From the above construction it will be seen that a very strong and powerful
field of force for the diaphragms of the telephones may be produced and at a com-
paratively small expense, as the strength of the call' bell magnets is used in addition
to the ordinary permanent magnets of the telephone: för producing this field; and it
will be found that the operation of the generator in no way interferes with the opera
tion of the telephones and the telephone:magnets:assististrengthening the compound
magnet of the generator.
It is therefore possible to get strong magnetic impulses to produce the signals on
the bells, which are especially desirable in long distance telephony, as well as being
able to strengthen the telephones themselves.
In Figure 2 is shown a slightly different arrangement of magnets embracing the
same idea, the generating magnet being composed of two annular permanent
magnets 1, 2, in which the armature 16 rotates, and connected to this magnet is a
farger compound magnet composed of the permanent magnets 5, 6, 7, having a cut
away portion, and plates 22 secured thereto and adapted to support the telephone, as
described with reference to Fig. 1.
.
Fig. 3 shows a somewhat simpler form, in which the compound magnet is made up.
of permanent magnets 1, 2, 3, having a cut away portion, and upon the extremities of
which are placed the transmitting and receiving instruments.
Figs. 4 and 5 illustrate a different arrangement in which the compound magnet is
made up of a number of separate annular magnets 1, 2, 3, etc. Secured to the opposite
sides of this magnet are the permanent magnets 9, 10, which are united to the annular
magnets by dovetailed joints, as indicated, so as to firmly hold them in place. The
free ends of these magnets are tapered to nearly their extremities, which latter, how-
ever, are preferably made cylindrical to better support the coils 13 of the telephone.
The armature 16 is in this instance mounted in a non-conducting frame secured to the
annular magnets and: driven by cog wheels 18, 19, as before.
Figs. 6 and 7 show another form in which the permanent magnets are made up of a
series of strands of steel wire or rope, each strand being preferably made up of a
number of smaller wires or strands of hardened steel, and the whole suitably twisted
together in the ordinary way to make a rope or cable, and when such rope is not
sufficient a number of them can be bent to make the compound magnet of any
desired form and strength. In this way the compound magnet consists of a large
number of independent magnets, as each wire strand is a permanent magnet in itself,
and as they are closely bound together and twisted,, so that each and every strand
comes into magnetic contact with each and every other strand, there is a perfect
magnetic contact throughout, and at the same time each magnet retains its individuality
to a certain extent. The magnets are preferably provided with steel extensions 24,
which form the poles of the rope magnets, and between which the armature revolves,
being driven by the gears 18, 19. These gears are shewn in Fig. 6 as being provided
with a handle connected to an ordinary bell pull 29, for operating the same and in
Fig. 7 there is slightly a different arrangement shown, a sprocket wheel and
chuin 30, 31, being used, and a retracting spring 32, being used in place of the
weight 34 in Fig. 6.
In all these instances the gear wheels are preferably made of buffalo or other hide,
which, being non-magnetic and a non-conductor, interferes in no way with the
magnetic conditions of the machine and they have the further advantage of being
practically noiseless.
While any of the ordinary forms of magnetic telephones may be used it is preferred
to employ the construction shewn in Fig: S-in which one of the poles 10 of the com-
pound magnet shown in 'the previous figure has an iron core 11 mounted thereon
supporting the coiF14. The diaphragm 15 is mounted in a box or frame 40 connected
to a tube 41, having an internal screw thread adapted to engage with an external
screw thread upon the tube-42 of the mouth piece 43. This mouth piece is provided
with a ring or depression 44, in which bears a supporting collar 45, secured to the box
or frame-46, mounted on the pole 10.
By this arrangement it is possible to accurately and equally adjust the diaphragm

page_text: with relation to the core piece 11, by simply turning the mouth piece 43 to the right
or left, as the case may be, thereby advancing or retiring the case 40 with the
diaphragm supported therein. Furthermore, the diaphragm and magnet are prac-
tically enclosed within two cases, which prevents interference from extraneous
disturbing causes.
The diaphragm is preferably non-metallic and non-magnetic, and is composed of a
sheet or sheets of pyroxyline compound, the surface of which has been properly
treated, as with an alcoholic solution of benzoine or camphor, or its equivalent, and
impregnated when so softened with iron filings which are preferably distributed over
the surface so as to concentrate near the centre of the diaphragm, as indicated in
Fig. 9. In place of the iron filings, however, fine wires may be stretched across the
pyroxyline diaphragm and be imbedded in the surface thereof.
While various ways of embodying the invention have been indicated it is not desired
to limit the scope of the present application to the precise arrangement and construc-
tion shown as the principles involved may be readily applied to other forms and
arrangements by those skilled in the art.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is :-
-
1. The combination with the annular magnet and armature rotating therein, of
extension pieces connected to the magnet and supporting the coils of the telephone,
substantially as herein set forth.
2. The combination with an annular magnet and armature arranged therein, of
extension pieces connected to the magnet formed with tapering ends supporting the
telephone, substantially as set forth.
3. The combination with an annular compound magnet and armature therein, of
extension pieces connected thereto by dovetailed joints and supporting the telephone,
substantially as described.
4. For use with magneto telephones a permanent magnet consisting of a number
of strands twisted together, each strand consisting of a series of independent steel
wires, substantially as described.
5. For use with magneto telephones the combination with the compound magnet
made up of a number of strands of steel wire twisted together, polar extensions con-
nected to the wires, an armature rotating between the poles, and driving gear for the
armature supported upon the magnet, substantially as described.
6. The combination with a permanent magnet pole, of a core mounted thereon
sustaining a coil, a box mounted on the magnet pole, a mouth piece mounted in the
box, and a case supporting the diaphragm of the telephone connected to and operated
by the mouth piece, substantially as described.
7. The combination with the permanent magnet pole, of a core fixed thereon sup-
porting a coil, a case surrounding the core supporting the diaphragm, and means for
adjusting the diaphragm and case with relation to the core and magnet, substantially
as described.
8. In a magneto telephone, a diaphragm of pyroxyline compound having magnetic
material imbedded in one surface, substantially as described.
Dated this 27th day of March 1080
PHILIP M. JUSTICE.