Year: 1888

page_text: Date of Application, 24th July, 1888
Specification Accepted, 31st Aug., 1888
United States of America, Electrician.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex, M.I.M.E.
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 to transmitting instruments for transmitting electrical
impulses over a line circuit, and is designed for use in conjunction with the
improved electrical type-writer which operates as a receiver and forms the subject
matter described in specifications Nos. 7202 and 10,663 of 1887. The improved
transmitter is utilised to convey or transmit electrical impulses by the manipulation
of the keys of the instrument at one extremity of a main line circuit, to a similar
instrument located at the other extremity of said line, and this organization of
apparatus is used in connection with a printing telegraph, or with any suitable
receiver which records the message in legible form each transmitter at the respective
stations in the line circuit being suitably electrically connected with such local
receiver, so that by the manipulation of the keys of the transmitter at one end of a
line, the electrical impulses are sent from a suitable source of electricity, and do
synchronously and simultaneously actuate the registering mechanisms of such local
receivers.
This invention consists in a certain organization of apparatus, arrangement and
combination of parts, and electrical connections, all of which will be particularly and
definitely described hereinafter.
Referring to the accompanying drawings:
Fig. 1 is a front elevation of the improved instrument the exterior casing being
detached for inspection of the interior parts.
Fig. 2 is a side elevation of the same together with the key-board thereof.
Fig. 3, is a detail top plan view of the contact points of the key-board, and the

page_text: cirent closer for throwing all the said contacts electrically in circuit with their
respective segments.
Fig 4 is a diagrammatical view, showing the transmitting instrument in circuit
with a local receiver which corresponds to the construction of the electrical type-
writer heretofore described by me in other Letters Patent.
Fig. 5 is a modification of the electrical spring contact shown in fig. 2.
Like numbers of reference mark similar or like parts in the several views of the
drawings.
Referring to the drawings by numbers;
1, indicates an upright supporting frame carrying the superincumbent parts, and
is secured to the horizontal base 2, of the instrument in any suitable manner.
Upon the base 2, is mounted the key-board of the instrument, which is constructed
as follows:—
3, designates a rectangular elevated frame-work which extends transversely across
the key-board and serves as a support for the pivot-bar 5, of the series of circuit
closing levers 4, 4, which are, respectively, insulated from and pivotted upon the said
pivot-bar, which, in turn, is trunnioned at each extremity by a small arbor or stud
in the said frame 3; and at the other end of the key-levers 4, 4, are placed the
finger-keys 6, 6, which carry the letters, characters, or symbols of the key-board, and
on the under side of each key lever, and near the forward extremity thereof, is
provided a depending contact point 7, which is designed to engage its respective
contact 8.
The said contacts 8, 8, are arranged in the same horizontal line upon the base 2, of
the key-board, and are provided near their centre (as shown in Fig. 2) with the
projecting bevelled bosses or flanges 9, 9, for a purpose hereinafter explained.
10, designates a link rod of insulating material, parallel with the line of contacts 8, 8,
and pivotally connected at its forward extremity to the hand lever 11, and further
provided with a series of link contact plates 12, 12, which in their turn, are each
pivotted at one end to the screws 13, 13, and at their other ends to the link rod 10,
and correspond in number to their respective contacts 8, 8.
These contact link plates 12, 12, project each between any two of the series of
contact points 8, 8, and when shifted in either direction by the hand lever 11, are
adapted to engage and slip under the flanges or bosses of their respective contact-
points 8, 8; thus it will be seen that by shifting the said switch lever 11, in one
direction, each contact point 8, 8, is electrically connected with the wire 40, by its
respective link 12, while on the other hand if the position of the parts remains as
shown in Fig. 3, the circuit will be open at each contact point 8.
The several circuit closing key-levers 4, 4, are formed of metal, and are alternately
of different lengths, as shown in Fig. 2; that is to say, the series of longer levers
terminating in the finger keys of the outer row of the key-board, while the shorter
levers carry the finger keys of the inner row; however, as will be observed by an
inspection of Fig. 2, the contact points 7, 7, which are arranged on each key-lever
are in the same horizontal and vertical plane with the contacts 8, 8, so as to precisely
and accurately engage their corresponding contacts 8, 8, when any lever 4, is
depressed by its finger key 6. Although I have shown and described the key-board
arranged in alternate banks or rows, I do not confine myself to such construction,
as it will be readily understood that the same may be constructed in any suitable
manner for convenience in manipulation.
14, 14, indicate a series of retracting springs, one for each key-lever, and each
having its lower extremity secured to the base 2 and its upper end attached to its
adjusting screw 15 which latter enters through a suitable aperture or perforation in
its respective key-lever 4; and 16, 16 are a series of limiting screws mounted through
apertures in the frame 3 and are so arranged as to restrict or limit the upward play
or reciprocation of their respective key-levers 4, 4 and are tipped at their inner ends
with pieces of insulation 17 1or the obvious purpose of preventing electrical contact
with any key-lever 4.
Upon the upper portion of the vertical frame-work 1 is placed a series of current

page_text: conducting segments 18 18 arranged as shown in Fig. 1, in the arc of a circle and
each insulated from the next adjacent segment and all supported in an elevated
position by the hard rubber or other insulation 19 (see Figs. 1 and 2).
20 represents a vertical plate arranged parallel to the frame 1 and serving to support
the different co-operating parts of the clock-work motor 21, which comprises in brief,
a train of wheels actuated normally by a weight and cord or other suitable motive
power, and is arranged and constructed as follows:-
The train of wheels of this step-by-step motor are set into motion by the large
pinion or gear wheel 21 which is mounted loosely on the winding shaft 22 and is
provided with a pawl-dog 23 adapted to engage the teeth of the ratchet wheel 24
which in turn is either keyed rigidly upon the shaft 22 or formed integral with the
drum 25 which latter is mounted rigidly upon the said shaft 22.
The ratchet wheel 24 is revolved normally by the cord. 26 provided with a depending
weight 33 (shown in Fig. 1).
However it will be apparent that the equivalent of such construction would be a
spring arranged to normally rotate said drum. The wheel 24 meshes with the small
pinion 27 (shown in dotted lines in Fig. 1) which pinion is mounted rigidly on the
shaft 28 which carries the gear wheel 29.
30 is another pinion mounted rigidly on the shaft 31 and meshing with the
wheel 29 whereby rotary motion is imparted to said shaft 31, which, in turn,
carries the actuating scape-wheel 32. 34, indicates an ordinary pivotted escapement
lever placed in proper relation to its scape-wheel 32, and arranged to be oscillated
back and forth by the movement thereof; this lever is made of metal, and is
pivotted upon the shaft 35, which, in turn is trunnioned in the centre of the surface
of the upright frame 1, (as shown clearly in fig. 1) so that the play of said lever
to either the right or left encompasses the same area of the segments 18, 18, or in
other words, since the normal position of the lever as shown in fig. 1, is parallel
with the central line of the frame 1, it has equal play upon the segments 18, 18, no
matter to which side it may be vibrated by the scape-wheel 32.
Upon the forward free end of the lever 34, is formed a laterally projecting
boxing 36, containing the spring actuating contact pin 37, which, by means of the
coiled spring 38 is kept normally in contact with a segment 18 so that during the
vibration of the lever to and fro perfect electrical contact is made between pin 37 and
the successive segments 18 as will be apparent.
However instead of this construction it is sometimes advisable to use in practico,
the arrangement shown in Fig. 5 in which for the contact pin 37 and spring 38 a
slightly compressed coiled spring 39 with the surface of the spirals in contact with
the segments is substituted the extremities of said springs 39 being sufficiently rigid.
to offer resistance to the longitudinal expansion of its coils.
;
The series of segments 18 18 correspond in number and relative situation to their.
respective link plates 12 12 key-levers 4 4 and finger keys 66 of the key board and
each segments 18 is connected electrically with its corresponding contact link 12 by
the wire 40 and branch wire 40 a; while each contact point 8 is electrically connected'
with one terminal of a printing magnet in the receiving instrument by wire 41; the
other terminal of said magnet being in circuit with the ring 43, by wire 42. The
ring 43, is in circuit with one pole of the battery 44 through wires 45 and 47 and
the spacing magnets 46.
Each link contact 12 as before stated is in circuit through its pivot screw with its
corresponding segment 18 by wire 40; and thus it will be seen that when all the link
plates are in contact with their respective contact-points 8 8 the latter are severally in
circuit with their respective segments.
The escapement lever 34 is in circuit with the line 49 by the brush 48 which bears
normally upon the pivotal support 35, of said lever.
Before proceeding further into the description of the operation of the invention, I.
will first preface a short explanation of the character and operation of the class of.
receiving instruments shown in circuit with the invention, and shown, described, and
claimed in the before mentioned other applications for patents, so that a clear and.

page_text: comprehensive understanding may be had of the improvements hereinafter claimed.
Accordingly I will say that each key-lever 4 is so arranged that a depression thereof
will cause an electrical impulse to be discharged from the sources of electricity
simultaneously through an electric magnet, which corresponds to the key-lever
depressed, said impulse causing the energization of said magnet and thereby effecting
the attracting of its armature, which action forces the impact of a type-lover depressed
against the ordinary travelling paper-roll; the same impulse passes into the spacing
magnets of such receiving instrument which are of a higher resistance than the
printing magnets and act sluggishly, thereby energizing said spacing magnets and
operating the step-by-step motor at a determinate instant after the registration of the
particular letter has been made upon the paper-roll; and finally the same electric
impulse in its passage over its path through the transmitting instruments at both
extremities of a line circuit, and over the line, is utilized to similarly effect the
registration of a like character in a receiving instrument of similar construction
at a distant station.
It is not thought necessary to enter more fully into a detailed description, since
sufficient has been described to enable any one skilled in the art to which this
invention appertains, to comprehend the operation of the receiving instrument in
conjunction with which the invention is used; and moreover since the novelty of
this instrument is not at all dependent upon the nature of the receiver employed.
Two of these transmitting instruments each being of the construction herein before
described are placed each respectively at one extremity of a line circuit as shown con-
ventionally in Fig. 4 which for the sake of convenience will be hereinafter referred to
as theoretically representing two stations, since the operation at the two ends of the
line is identical. The train of wheels for imparting vibrating motion to each escape-
ment lever 34 34 of the two transmitting instruments are exactly alike in construction,
pattern &c., and their actuating weights are the same; all of which is for the purpose
of maintaining perfect synchronism between any two levers 34 34 which may be
included in a line circuit; or in other words the object of this clock work motor
applied to two widely soparated escapement levers is for the purpose of making all the
vibrations of both levers relatively equal in speed, duration of time and extent of
stroke, so that when the forward free end of the lever 34 at one station is upon a
segment 18 its corresponding lever 34 at another station will be upon a correspondingly
situated segment whether both of the arms are vibrating or are stationary.
The operation of the invention is as follows:
Pre-supposing that Fig. 4 represents two stations included in the same line circuit
and that the clock-work motor of the respective transmitting instruments are operating
in synchronism :
The transmitting and receiving instruments being in the position shown in fig. 4
(which figure now represents a transmitting station) and the circuit closing switch for
the contacts 8, 8 being in the position shown in Fig. 3, and the operator at the
transmitting station desiring to convey a message; say for example, the word
"DYNAMOGRAPH" over the line 49 to a distant station, he successively de-
presses the keys 6, 6 which carry the letters comprising this stipulated message;
now in order to clearly follow this operation we will suppose that the first key,
corresponding to the letter D is that carried by the long key-lever in Fig. 2;
consequently, the depression of said key causes an electrical impulse to be dis-
charged from the battery 44, through wire 47, spacing magnets 46, wire 45, and
around the ring 43, into the printing magnet of the receiving instrument, through
which the circuit is closed by the depression of the said key energizing the same and
causing its pivoted armature to be attracted which action effects the impact of the type
lever up against the paper carried and fed by the travelling paper-roll then the said
spacing magnets 46 being more sluggish in their action than the printing magnets
the same impulse will energize said spacing magnets at a determinate instant after
the impact has been made, in the manner before stated, upon the paper-roll, and
will thereby effect the advancement of the travelling carriage one letter space, ready
for the next letter to be printed.

page_text: Simultaneously with the energization of the printing magnets and the imprint of
the letter "D" at the transmitting station, the current will traverse the particular
wire 41, connecting the printing magnet with its respective contact point 8 (see Fig. 2)
up through the contacts 7, and 8, the lever 6, the branch wire 40 a, and the wire 40, to
the particular segment 18, which corresponds to the key depressed; and the escape-
ment lever 34 vibrating as before stated, rapidly over the surface of the series of
segments 18, and being in perfect synchronism with the corresponding lever 34, at
the receiving station; the current will pass from this segment 18, through the pin 37,
spring 38, lever 34, brush 48, to the line 49, and over said line to the distant or
receiving station, which may also be conventionally represented by Fig. 4; therefore,
the current having passed over the line 49, as before stated, to the distant station, and
the circuit closing switch shown in Fig. 3, being so adjusted as to connect all the
contacts 8, 8, electrically in circuit with their respective segments 18, 18, the said
current will pass over its path 49, 48, 34, to its particular segment 18, which
corresponds both to the key depressed at the other station and to the segment 18, corro-
sponding to said koy at such station, and now, it being understood that the lever 34,
at the receiving station is in synchronism with its corresponding lever at the
transmitting station, and that the switch-lever 11 has been shifted so as to electrically
connect each contact point 8 at said receiving station, with its respective segment 18
the current may be traced over its path as follows:
From the segment 18, wire 40, screw 13, link contact plate 12, contact point 8,
wire 41, into the printing magnet of the receiving instrument corresponding to the
printing magnet at the transmitting station, which has been previously described as
being energized, thereby effecting the imprint of the particular type lever correspond-
ing to the letter "D" upon the paper-roll, and the operation of the letter spacing
mechanism in the same manner as at the other end of the line.
Thus, the operation is repeated until the end of the word "DYNAMOGRAPH" is
reached; should it now be desirable to make a space between the word completed
and the next to be printed, a spacing key (not shown) of the transmitting instrument
is depressed, thereby transmitting an electrical impulse over the line and through
both transmitting and receiving instruments and effecting a space between the words
without making an imprint upon the paper at either station.
The spacing key of the transmitting instrument is merely auxiliary in its functions,
serving only to energize the spacing magnets in the respective receivers, and to
transmit the desired electric impulse; therefore, as the means for making the desired
spaces without effecting an imprint, forms a part of the construction of the receiving
instrument forming the subject-matter of the before mentioned other applications and
patents, it will not be further dwelt upon herein.
In order to transmit from the distant station back to the transmitting station, an
inverse arrangement or the respective circuit closing switches is all that is required.
Suitable means may be provided for either separately or jointly stopping or starting
the synchronal motors when the instruments are arranged, respectively, at two or
more stations; however, this feature is designed for a separate application and will
not be described herein.
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. In a transmitting instrument the combination with a series of segments each
electrically connected with a circuit controller; of a vibrating commutator electrically
in contact with said segments and included in a line circuit; the circuit; and a
circuit controlling switch for connecting and disconnecting said segments with the
circuit.
2. In a transmitting instrument the combination with a series of current conducting
segments of mechanism for severally directing electric impulses through said segments;
an electric circuit including said segments; a circuit controlling switch for connect-
ing and disconnecting said circuit with said segments; a commutator arm vibrating

page_text: electrically in contact with said segments; and a synchronal motor for vibrating
said arm.
3. In a transmitting instrument the combination with a series of segments elec-
trically in circuit with a series of corresponding circuit closers; suitable contacts for
said circuit closers in circuit with a source of electricity; a lever-switch for severally
connecting the series of contacts with the series of segments; a vibrating arm
electrically in contact with said segments and included in a line circuit; and a line
circuit; substantially as described.
4. The combination of two instruments respectively placed at separate stations in a
line circuit, and each comprising a series of segments; circuit closing mechanism
for directing the current severally through said segments; a vibrating arm electrically
in contact with said segments; a mechanical synchronal motor for vibrating said arm;
and a circuit changing switch for cutting the source of electricity in or out of circuit
with a series of segments; substantially as described.
5. The combination with a series of contacts in circuit with a source of electricity,
of a series of segments; and a levor-switch for severally electrically connecting and
disconnecting said contacts with said segments; substantially as described.
6. The combination with a series of current conducting segments respectively in
circuit with a series of pivotted contacts; a series of pivotted contacts operated in
unison by a single movement of a lever; a shifting lever for said pivotted contacts;
and a series of stationary contacts adapted to be electrically connected with their
respective pivotted contacts by the single movement of a lover; substantially as
described.
7. The combination with a series of insulated current conducting segments charged
from a suitable source of electricity; of a moving arm provided with a spiral spring
contact electrically in circuit with said series of segments; substantially as described
Date thin 24th two of ful., 1000
W. P. THOMPSON & BOULT,
Agents.