IMPROVEMENTS IN ELECTRO-MAGNETIC TELEGRAPHS
Year: 1863

page_text: LETTERS PATENT to Henry Wilde, of the City of Manchester, Engineer,
for the Invention of "IMPROVEMENTS IN ELECTRO-MAGNETIC TELEGRAPHS."
Sealed the 25th April 1863, and dated the 25th February 1863.
PROVISIONAL SPECIFICATION left by the said Henry Wilde at the
Office of the Commissioners of Patents, with his Petition, on the
25th February 1863.
I, HENRY WILDE, of the City of Manchester, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN ELECTRO-MAGNETIC
TELEGRAPHS," to be as follows:-
My Invention consists in improvements in the transmitting instruments
described in the Specifications of Letters Patent granted to me on the Eighth
day of April and on the Tenth day of August One thousand eight hundred
and sixty-one, and numbered 858 and 1994 respectively.
In the Specifications of these Patents transmitting instruments are shewn and
described in which the armature of a magneto-electric machine is mechanically
geared with a radial arm which travels beneath a series of finger keys, any
one of which being depressed arrests the motion of the radial arm and also the
motion of the armature with which it is mechanically connected.
In the present improvement the alternately "inverted" currents (or
currents passing in opposite directions) generated during the continuous revo-
lution of the armature of a magneto-electric machine, are made to pass in one

page_text: and the same direction by means of a "commutator" or current changer of
the ordinary construction placed on the armature or other axis connected with
the ends of the wires in which the currents are generated. These "direct"
currents are then transferred by means of wires to another commutator by
which the currents are again inverted previous to their passing into the
telegraphic circuit. This last-mentioned commutator is made to revolve more
slowly than the other so as to allow two or more of the direct currents from
the first-mentioned commutator to pass into the telegraphic circuit before the
currents are again inverted. From the relation which the more slowly
moving commutator bears to the more quickly moving commutator of
the magneto-electric machine, I call it a differential commutator. This
differential commutator is fixed on the axis which carries the radial arm
and index finger of the transmitting instrument or other axis geared with
it, and is so constructed as to invert the current from the other commutator
as many times as there are letters or signs on the dial of the indicating
instrument. In the above described arrangement none of the moving parts
of the magneto-electric machine are mechanically connected with the differen-
tial commutator nor with the moving parts of the transmitting instrument, both
of which may be driven either by separate or the same moving power; provided
always that the number of direct currents or shocks proceeding from the com-
mutator of the magneto-electric machine are generated at a rate of not less than
twice the number of times that they are inverted by the differential commutator.
The currents or shocks generated and propagated simultaneously from a number
of magneto-electric machines may be regulated in the same manner as from one
machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Wilde in the Great Seal Patent Office on the
25th August 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
WILDE, of the City of Manchester, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of February, in the year of our
Lord One thousand eight hundred and sixty-three, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Henry Wilde, Her special license that I, the said Henry ;
Wilde, my executors, administrators, and assigns, or such others as I; the
I,

page_text: said Henry Wilde, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN ELECTRO-MAGNETIC TELEGRAPHS," upon the condition (amongst others)
that I, the said Henry Wilde, my executors or administrators, by an instrument.
in writing under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that. I, the said Henry Wilde, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say):-
My Invention consists in improvements in the transmitting instruments
described in the Specification of Letters Patent granted to me on the Eighth
day of April, and on the Tenth day of August; One thousand eight hundred
and sixty-one, and numbered. 858, and 1994 respectively..
In the Specifications of these Patents transmitting instruments are shewn
and described, in which the armature of a magneto-electric machine is mecha-
nically geared with a radial arm, which travels beneath a series of finger keys,
any one of which being depressed arrests the motion of the radial arm, and
also the motion of the armature with which it is mechanically connected.
In the present improvement the alternately "inverted" currents (or currents
passing in opposite directions) generated during the continuous revolution of
the armature of a magneto-electric machine are made to pass in one and the
same direction by means of a "commutator" or current changer of the ordi-
nary construction placed on the armature or other axis connected with the ends
of the wires in which the currents are generated. These "direct currents
are then transferred by means of wires to another commutator, by which
the currents are again inverted previous to their passing into the tele-
graphic circuit. This last-mentioned commutator is made to revolve more
slowly than the other, so as to allow a greater number of the direct currents
froin the first-mentioned commutator to pass into the telegraphic circuit before
the currents are again inverted. From the relation which the more slowly
moving commutator. bears to the more quickly moving commutator of the
magneto-electric machine, I call it a differential commutator. This differential

page_text: commutator is fixed on the axis which carries the radial arm and index
finger of the transmitting instrument, or other axis geared with it, and is so
constructed as to invert the direct current from the other commutator as
many times as there are letters or signs on the dial of the indicating instru-
ment.
•
And in order that my Invention may be fully understood and readily carried
into operation, I will proceed to describe the accompanying Sheet of Drawings
reference being had to the figures and letters marked thereon.
Figure 1 is a front elevation of an alphabetical dial telegraph, to which my
improvements are applied; Figure 2 is an end view, and Figure 3 a plan, and
Figure 4 a plan with the covers of the magneto-electric machine and trans-
mitting instrument removed.
a, a, are the standards, and 6 the table on which the magneto-electric
machine c, and the transmitting instrument d, are placed, which are driven by
the treadle e, connecting link f, and crank shaft g, on which is fixed the
pulley g¹ for driving the pulley d¹ fast on the commutator shaft h of the trans-
mitting instrument d. The tension of the band passing around the pulleys d'
and g is regulated by the pulley d³, mounted on a stud which is adjustable on
the slide pillar d³.
The transmitting instrument is similar to that described in the Specification
of Letters Patent granted to Jacob Brett on the Eighth day of February One
thousand eight hundred and forty-eight, Number 12,054, with this exception,
that in the present arrangement the currents are inverted by means of the
"commutator" h, seen best in Figures 5 and 6, whereas in Brett's Patent they
were only interrupted by means of a make and break wheel.
In the present arrangement the radial arm travelling beneath the finger keys
as described in the above-mentioned Specifications of Letters Patent granted
to me on the Eighth day of April and Tenth day of August, One thousand
eight hundred and sixty-one, and numbered respectively 858 and 1994, is driven
by a worm and worm wheel as described in the Specification of Letters Patent
also granted to me on the Third day of December One thousand eight hundred
and sixty-two, Number 3240. The springs h* and h³ are respectively con
nected to the line and earth wire terminal screws ; and j', see Figure 3. On
the crank shaft g is also fixed the grooved wheel g³, for driving the pulley c¹,
fixed on the armature shaft i. The tension of the band passing around
the grooved wheel g and pulley c¹ is regulated by the pulley c³, mounted
on a stud in the radiating lever c³.
The magneto-electric machine which I prefer to use is shewn in detail in
Figures 7, 8, and 9; in these views it is shewn supported in a frame for the

page_text: purpose of being driven by a separate moving power, whereas in Figure 4 it
is shewn attached to the table, and it is driven by the same moving power as
the transmitting instrument. The cylindrical soft iron armature k is grooved
at each side to receive the coils of insulated wire wound in the direction of the
axis of the armature, and the armature shaft i is connected to the armature k
in the usual manner; to the other end of the armature is connected the stud of
the "commutator" l. This commutator is formed of two cylinders of hardened
steel insulated from each other, and instead of being cut parallel to the axis as
shewn in Figure 5 is cut diagonally in order that it may run more freely over
the springs bearing upon it; the armature k revolves in a cylinder formed of
the two outer pieces of iron k¹ and the intermediate piece ³, made of brass or
other non-magnetic substance, and the bolts by which the three pieces are con-
nected are also made of non-magnetic substance. The horse-shoe magnets m
are connected to the iron pieces k', by the bolts clearly shewn in the Drawing.
The armature is kept concentric with the commutator end of the magnet
cylinder by the tail pin k³ passing through the brass cross piece k*, and at
the other end by a conical shoulder on the shaft passing through the brass
cross piece. In Figures 1, 2, 3, and 4 the end of the armature shaft i is
supported in an adjustable bearing to keep the armature concentric with the
magnet cylinder. The switch n when turned against the stop n' short circuits
the coils of the magneto-electric machine until the crank shaft g has acquired
its regular motion, after which it is again brought into the central position
shewn in Figure 1, and the coils are then in direct communication with the
line wire and indicating instrument o.
The mode of operation is as follows:-Motion is given to the armature k,
which produces two currents or shocks for each revolution; these currents after
being made to pass in one direction by the commutator 1, are transferred by
means of the springs and wires land to the spring P, and to the metal
base of the transmitting instrument, which are respectively in connection with
the separate and insulated parts of the commutator h', motion is also given
simultaneously to the commutator h¹, and the relative speed of the commutator 1,
and the commutator h¹ is such that the currents proceeding from the magneto-
electric machine are produced about one-fourth faster than they are inverted
by the commutator h¹. When the magneto-electric machine is driven by
steam or other separate moving power the currents may be produced relatively
faster than is necessary when the magneto-electric machine and the transmitting
instrument are driven by the same moving power, for the purpose of keeping
the speed of the former in excess of the latter when the most expert operator
is working the instrument. Wires are connected from the place where the

page_text: magneto-electric machine is driven to the transmitting instrument d, which is
driven by the treadle e, as above described.
When the machine shewn in Figures 1, 2, 3, and 4 is in operation the
inverted currents from the commutator h¹ pass into the telegraphic circuit and
act upon the indicator o in the manner described in the Specification of
Letters Patent granted to me on the Eighth day of April One thousand eight.
hundred and sixty-one, Number 858, until the radial arm is arrested by the
depression of a finger-key which stops the commutator h, and prevents the
currents from the commutator of the magneto-electric machine from being.
inverted, and which currents then pass into the telegraphic circuit in one
direction only, and from the well-known construction of the magnetic apparatus,
connected with the indicator which requires inverted currents to produce the
rotary motion of an index around the dial, the direct currents from the: magneto-
electric machine will not produce any effect on the indicator, and the index
of the indicator will therefere remain opposite the letter required so long as a
finger-key is pressed down. When the pressure of the finger is removed from
the key the commutator h¹ again inverts the currents which actuate the'
indicators until the commutator is again stopped by the depression of another
key. During the depression of a finger key the band slips over the pulley d'
in the usual manner, while the driving shaft g and armature continue their
motion as before.
..
Having thus stated the nature of my Invention, and described the manner.
of performing the same, I wish to observe that I make no claim to the peculiar
construction of the armature marked k, in Figure 9, nor to the form of the
commutator marked h', in Figures 5 and 6; I would also remark that I do
not limit myself to the details given, but what I do claim is,-
Firstly, regulating currents of magnetic electricity as herein described by
the differential motion of the commutator of a magneto-electric machine and
the commutator of the transmitting instrument of an alphabetical dial
telegraph.
Secondly, driving the commutator of a magneto-electric machine and the
commutator of the transmitting instrument of an alphabetical dial telegraph
directly or indirectly by the same driving shaft or moving power..
Thirdly, the method of constructing the magnet cylinder k¹, k³, k, and.
cross piece k, for holding the tail pink, on which the armature revolves as
described.
Fourthly, the method of constructing the steel cylinders forming the com-
mutator of a magneto-electric machine as described.
Fifthly, and lastly, the methods of adjusting the tension of the driving.

page_text: bands of the magneto-electric machine, aud transmitting instrument as
described.
In witness whereof, I, the said Henry Wilde, have hereto set my hand
and seal, this Twenty-fourth day of August, in the year of our Lord
One thousand eight hundred and sixty-three.