IMPROVEMENTS IN TRANSMITTING AND RECEIVING APPARATUS FOR TYPE PRINTING TELEGRAPIIS
Year: 1881

page_text: LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for an
Invention of IMPROVEMENTS IN TRANSMITTING AND RECEIVING APPARATUS
FOR TYPE PRINTING TELEGRAPIIS." A communication from abroad by Henry
Van Hoevenbergh of Elizabeth in the State of New Jersey United States of
America, Electrical Engineer
PROVISIONAL SPECIFICATION left by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 27th December 1881.
"IMPROVEMENTS IN
SYDNEY PITT of Sutton in the County of Surrey
TRANSMITTING AND RECEIVING APPARATUS FOR TYPE PRINTING TELEGRAPHS."-
[A communication from abroad by Henry Van Hoevenbergh of Elizabeth in the
State of New Jersey United States of America, Electrical Engineer.]
This Invention relates to type-printing telegraphs in which the type wheels of
the receiving instruments are impelled by a weight or spring, acting through
suitable intermediate wheel-work and the progressive movements of said type-
wheels are controlled by a series of electrical pulsations alternately of opposite
polarity, which are transmitted over the main line from the sending station.
These pulsations cause the rapid to and fro vibration between electro magnets of
an armature, suitably constructed to be actuated by such alternating currents and
the vibrating in turn controls the type wheel, by means of a step by step escapement,
of well known construction.
In the improved apparatus the printing is effected by increasing the strength of
the electric current during some one of the pulsations without reference to its
polarity, at the instant the required division or character of the type wheel is
opposite the platen, and this action takes place without retarding the progressive
movement of the type wheel, or interrupting the regular succession of electric
pulsations. The momentary stoppage of the type-wheel shaft at the termination

page_text: of each vibration of the step-by-step escapement, affords sufficient time to permit
an impression to be taken from the type wheel by means of proper mechanism.
The receiving or printing instrument is provided with a double type-wheel
consisting of two type-wheels fixed side by side upon the same axis, and an
oscillating printing platen is made use of by means of which either one of the two
type wheels may be printed from at the will of the transmitting operator.
In the organization of electric circuits for operating the apparatus, two inde-
pendent main lines are required. The currents transmitted over the first line
control the progressive movement of the type wheels, and also actuate the printing
mechanism. The currents over the second line control the angular position of the
oscillating platen, and thus determine from which of the two type-wheels a given
impression shall be taken, and the currents upon this line also actuate the unison;
mechanism, by means of which the synchronism between the transmitting and
receiving instruments is maintained.
The oscillating printing platen, herein before referred to is governed in its
movements by a clutch lever, in such a manner that either one of the three
different results may be produced by a given movement of the printing mechanism,
that is to say, either the letters of the alphabet upon one type wheel or the
numerals and other miscellaneous signs upon the other type wheel may be printed
or spaces or blanks may be made in the printed record, without the necessity of
waiting for the type wheels to reach the zero point.
The unison mechanism by means of which the synchronism between the
transmitting and the receiving instrument is maintained, is preferably actuated by
means of the same clutch that controls the oscillating platen hereinbefore referred
to, and its function is to automatically adjust the position of the_type_wheels-of-the-
-receiving-instrument when out of correspondence with the transmitter, by the
normal operation of the instrument acting at a particular point once during each
complete revolution of the type wheel.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Sydney Pitt in the Great Seal Patent Office on the 27th June 1882.
SYDNEY PITT of Sutton in the County of Surrey. IMPROVEMENTS IN
TRANSMITTING AND RECEIVING APPARATUS FOR TYPE PRINTING TELEGRAPHS"
A communication from abroad by Henry Van Hoevenbergh of Elizabeth in the
State of New Jersey, United States of America Electrical Engineer
This Invention relates to that class of printing telegraphs in which the type-
wheels of the receiving instruments are impelled by a weight or spring acting
through suitable intermediate wheel work, and the progressive movements of said
type-wheels are controlled by a series of electrical pulsations, alternately of opposite
polarity, which are transmitted over the main line from the sending station.
These pulsations cause the rapid to and fro vibration between electro magnets of
an armature suitably constructed to be actuated by such alternating currents, and
the vibrating armature in turn controls the type-wheel by means of a step-by-step
escapement of well known construction.
In the improved apparatus, hereinafter described, the printing is effected by
increasing the strength of the electric current during some one of the pulsations
without reference to its polarity at the instant the required division of the type
wheel is opposite the platen, and this action takes place without retarding the
progressive movement of the type wheel or interrupting the regular succession of
electric pulsations. The momentary stoppage of the type wheel shaft at the
termination of each vibration of the step by step escapement affords sufficient
time to permit an impression to be taken from the type wheel, by means of proper
mechanism. The receiving or printing instrument is provided with a double type
wheel, consisting of two type-wheels fixed side by side upon the same axis, and
an oscillating printing platen is made use of, by means of which either one of the
two type wheels may be printed from at the will of the transmitting operator.
In the organization of electric circuits for operating the improved apparatus
two independent main lines are required. The currents transmitted over the first
line control the progressive movement of the type wheels, and also actuate the
printing mechanism. The currents over the second line control the angular position
of the oscillating platen and thus determine from which of the two type wheels a
given impression shall be taken, and the currents upon this line also actuate the
unison mechanism by means of which the synchronisin between the transmitting
and receiving instruments is maintained.
The oscillating printing platen hereinbefore referred to is governed in its
movements by a clutch lever in such a manner that either one of three different
results may be produced by a given movement of the printing mechanism-that
is to say, either the letters of the alphabet upon one type wheel or the numerals
and other miscellaneous signs upon the other type wheel may be printed, or spaces
or blanks may be made in the printed record without the necessity of waiting for
the type wheels to reach the zero point, as in apparatus of this kind heretofore
constructed.
The unison mechanism, by means of which the synchronism between the
transmitting and the receiving instrument is maintained, is preferably actuated by
means of the same clutch that controls the oscillating platen herein before referred
to, and its function is to automatically adjust the position of the type-wheels of the
receiving instrument, when out of correspondence with the transmitter, by the
normal operation of the instrument acting at a particular point once during each
complete revolution of the type wheel.

page_text: In the accompanying Drawings, Figure 1, is a plan view of a portion of the
transmitting apparatus. Figure 2 is a front elevation of the same. Figure 3 is a
transverse vertical section of the key board which forms a portion of the trans-
mitting apparatus and Figure 4 is a plan of said key board, (the last two Figures
being on a reduced scale.) Figure 5 is a detached view of the pole changing
circuit-closer which transmits currents over the second line wire. Figure 6 is a
detached view showing certain details of the transmitting apparatus. Figure 7 is
a front elevation of the receiving and printing mechanism Figure 8 is a side
elevation of the same. Figure 9 is a front elevation showing the scape wheel
and its controlling mechanism. Figure 10 is a front elevation showing the
printing mechanism. Figure 11 is a side elevation of the same. Figure 11º is a
similar view showing the oscillating platen in a different position. Figure 12 is a
theoretical diagram illustrating the organization of the electric circuits and their
relation to the mechanical portions of the transmitting apparatus and Figure 13
is a diagram illustrating the construction of the electro-magnet of the receiving
apparatus.
The transmitting apparatus may conveniently be regarded as composed of four
divisions. The first of these controls the transmission of the alternate positive and
negative electrical pulsations by which the intermittent rotation of the double
type wheel of the receiving-instrument is effected.-The second produces a printed
impression of the required character upon the type wheel at the proper point in its
revolution. The third determines the specific character of the impression thus
produced at any given point in the revolution of the type wheel, and the fourth
readjusts, when necessary, the position of the type wheel at the receiving station,
and thus maintains its synchronism with the transmitting apparatus at the
sending station.
The first-part-of-the-transmitting-apparatus-consists-of-a-pole-changing-or-
battery reversing commutator, which is driven at a determinate and uniform rate
of speed by some suitable mechanical means. This "pole-changer," as it will be
hereinafter termed, is shown in Figures 1, 2 and 12. A shaft 1 is mounted in
suitable stationary bearings upon standards 2, 2 upon which shaft is fixed a piece
of hard rubber or other like insulating material 3. Upon this latter are mounted
four metallic contact points, 4, 5, 6, 7. Two metallic spring fingers, 8 and 9, are
so arranged with reference to the four contact points upon the hard rubber block 3
that when the shaft 1 is in one position (which is that shown in Figures 2
and 12) the spring 8 rests upon the contact 5 and the spring 9 upon the contact 7.
If, however the shaft 1 be rotated a short distance in the direction indicated by
the arrow in Figure 2, the spring 8 will be brought into contact with and will
rest upon the contact 4, and will be thereby lifted from the contact 5, and in like
manner the spring 9 will rest upon the contact 6 and be lifted from the contact 7.
The spring 8 is electrically connected through the post 10, wire 12, and binding-
Ecrew 13, with the positive pole of the main battery 14, and the spring 9 is in like
manner connected with the negative pole of the main battery 14 through the
post 11 wire 15, and binding screw 16. The contacts 5 and 6 are electrically
united with each other by a short conductor 17, and also with the line-wire 18,
through the wire 19 and binding post 20. In like manner the contacts 4 and 7
are united by the conductor 21, and are also connected through the wire 22, and
binding post 23 with the earth-wire 24. The line-wire 18, hereinafter termed the
first line wire," extends to the distant station or stations, as shown in the
diagram Figure 12, and there passes through the different electro-magnets which
control the movements of the type wheel and the printing mechanisin, respectively,
of the receiving instrument or instruments, as will be hereinafter described and
explained in detail. Thus it will be understood that if the shaft 1 hereinafter
termed a "rock-shaft" be caused to oscillate backward and forward, alternate
positive and negative pulsations from the main battery 14 will be transmitted over
the line 18, for the reason that the connections between the poles of the battery
and the line and earth wires are interchanged at each oscillation,
"

page_text: In practice any required number of separato or independent lines may be
operated from one key board and system of transmitting mechanism by making use
of as many separate commutators or pole changers as there are independent
lines to be operated and by mounting all these pole changers upon a single
rock shaft, which may be of any required length and will actuate all the lines in
unison.
The mechanical instrumentalities for imparting motion to the rock shaft and
pole changer herein before described consists of a shaft 25, (see Figures 1 and 12)
which is mounted upon suitable standards or bearings 26 26, and is provided
with a pulley 27 around which passes a belt or band from another shaft, (not
shewn in the Drawings) which latter shaft may be driven by any suitable motor
as for example an electro motor. By this means the shaft 25 is kept in continuous
and uniform rotation and the oscillation of the rock shaft 1 and its attachments
is effected thereby through the medium of certain mechanism which will now be
described. Upon the shaft 25 is fixed a wheel 28 hereinafter termed a "scroll-
wheel," the periphery of which is formed into alternate recesses or projections of a
wave like form as best seen in Figure 12.
Directly beneath and in the same plane of rotation with the wheel 28 is
mounted another precisely similar scroll-wheel 29. The number of projections
and recesses upon each of these wheels, taken together, is made equal to the
number of positive and negative impulses, taken together, which are necessary to
effect one complete revolution of the type wheel of the receiving instrument as
hereinafter described. The scroll wheels 28 and 29 are compelled to revolve
isochronously by means of spur gearing 30, consisting of two toothed wheels
having each a like number of teeth the upper wheel (seen in Figure 1) being fixed
to the shaft 25, and cominunicating motion therefrom to the lower wheel which is
directly beneath it upon the axis of scroll wheel 29. The scroll wheels 28 and 29
are so mounted with reference to each other that the projections of one wheel are
directly opposite the recesses of the other as they revolve, as will be understood by
reference to Figure 12. The space between the scroll wheels 28 and 29 is just
sufficient to admit a pin 32 which is inserted in the arm 33 of a right angled or
bell-crank lever 33, 34 mounted upon an axis, 35, the other arm 34 of which is
connected by a rod 36 with a crank-arm 37 fixed to the rock shaft 1. It will be
understood, therefore, that as the scroll wheels 28 and 29 revolve in the direction
denoted by the arrows an oscillatory motion will be communicated to the pin 32
which will be transmitted to the lever 33, 34, and thence to the rock shaft I, upon
which the pole-changer is mounted, and hence that the number of oscillations of
the latter during each revolution of the shaft 25 will be determined by the number
of projections and recesses upon the scroll wheels 28 and 29. From this it
necessarily follows that so long as the shaft 25 is kept in continuous rotation a.
determinate number of alternate positive and negative electric pulsations will be
transmitted over the line during each revolution which it makes. By means
hereinafter to be described the type wheel of the receiving instrument is caused to
revolve synchronously with the shaft 25 and its attachments.
The impression of any particular character upon the paper is effected at the
receiving station by increasing the strength of the electric pulsation which occurs
at the same moment the required character upon the rotating type wheel is
opposite the printing platen. The transmission of a pulsation of increased strength
at the proper time and in the proper sequence if effected by the following
mechanism (see Figures 1, 2 and 12.) Upon an upright plate 38 of hard rubber
or other suitable insulating material is mounted a segmental ring 39, technically
ternied a "sunflower." This consists of a number of metallic segments insulated
from each other and arranged in a circle, as shewn in Figure 2 These segments
are equal in number to the whole number of projections and recesses taken
together upon the scroll wheels 28 and 29. Upon a spring arm, 40, fixed upon the
shaft 25 is mounted a sliding contact point 41 hereinafter terined a " traveler"
which revolves within the segmental circle or sunflower and thus comes in

page_text: contact successively with the inner edge of all the segments during each of its
revolutions.
The key board is shown in cross section in Figure 3 and in plan Figure 4 both
of which Figures are on a reduced scale. The keys of the key board are arranged
in three rows, 42, 43 and 44 as seen in Figure 4. I prefer to place twenty eight
keys in each row, this being a sufficient number to provide for all the letters of the
alphabet, as well as the numerals and others characters ordinarily employed in
commercial telegraphy. The letters of the alphabet are arranged in the first
row 42, the numerals punctuation points and other signs in the third row 44
while the second row 43 consists of keys whose sole office it is to form blank
spaces between words or wherever needed in the communication to be printed. The
electrical connections of the key board will be best understood by reference to
Figures 3 and 12.
Each key consists of a vertical pin having a knob or button at
the top by means of which it may be depressed by the finger of the operator and
In spring for returning it to its normal position. The keys in row 42 are all
mounted in a long metallic rack, 45, and each one when depressed by the operator,
falls upon a corresponding tooth of the metallic comb 46 which extends the whole
length of the row of keys with its teeth extending underneath them. In like
manner the keys 44 are mounted in a separate rack 47, and act upon the teeth of
a comb, 48. The middle row of keys 43 are likewise mounted in a similar
rack 49; but when depressed they fall upon and make contact with a series of
insulated metallic springs 50 there being one such spring for each key in the row.
Each one of the series of springs 50 is permanently fastened to the base of the
apparatus at both of its ends, and extends underneath the ends of a tooth of the
combs 46 and 48, respectively, as will be understood_by_reference-to-Figures-3-
and 12. The springs 50-are electrically connected by means of a correspending
number of separate conducting wires, 51, with the corresponding insulated segments
of the sunflower 39.
The general principle upon which the key board sunflower and traveller act
together to increase the strength of a given electrical pulsation upon the line is
that of cutting out or short circuiting an artificial resistance normally interposed in
the main circuit during the time in which the traveller is passing over that segment
of the sunflower which corresponds to the particular key which is depressed upon
the key-board. The operation of the devices by means of which this is effected
will be best understood by reference to Figure 12. A rheostat or artificial
resistance 52 is placed in the main-line wire 18. Wires 53 and 54 are united
with the line wire 18, on each side of said rheostat. The wire 53 is connected with
the comb 48, and also, by a branch wire 55 with the comb 46. The wire 54 is
electrically connected with the shaft 25, and through that with the traveller 41.
The rack 49 of the middle row of keys 43 is also connected by a branch wire 56
with the wires 55 and 53. Hence it will be understood that whenever any key
whatsoever upon the key-board is depressed by the operator a shunt or circuit of
small resistance is closed at that point passing around the rheostat 52, which shunt
however is only completed so as to cut out the rheostat by the passing of the
traveller 41 over the segment of the sunflower corresponding to and connected with
the particular key which has been depressed; and, moreover, it is to be understood
that the shunt circuit through any particular segment of the sunflower may be
formed by either one of three different keys one in each row.
For example
referring to Figure 4 if the key lettered B is depressed, it will close the shunt
circuit, through the same segment of the sunflower as if the key marked with the
numeral 2 were depressed, or the unmarked space key immediately between the
two named. Whether the letter B, the numeral 2 or the space shall appear upon
the record at the receiving instrument is a matter that is determined by the action
of other and additional mechanism actuated through the second line wire, and
hereinafter to be described.
The mechanism for determining whether a letter, numeral or space shall be
printed by the receiving-instrument when the printing mechanism is actuated, and

page_text: for automatically securing synchronism between the transmitting and receiving
instruments, is actuated by means of an independent circuit or second line-wire,
which extends through the receiving instrument or instruments, and is preferably
operated by an independent battery at the transmitting.station. The electrical
currents or pulsations traversing this second main circuit are transmitted by a
special pole changing key, the movements of which are controlled by the apparatus
herein before described. This key consists of a horizontal metallic lever 57,
pivotted in the usual manner of a key at its centre 58. (See Figures 1, 2 and 12)
An L shaped arm 59 extends downward from the centre of the lever 57 passing
underneath or within the base and terminating in a flexible resilient upward
projection 60, which is clamped between the adjustable screws 61 and 62.
The object of this device is to maintain the key lever 57 normally in a horizontal
or central position, but to permit it to be inclined in one direction or the other in
response to the action of the electro-magnets 63 and 64 upon their armatures 65
and 66 which armatures are fixed upon the key-lever 57 at equal distance from
but on opposite sides of its fulcrum 58. The key lever 57 actuates certain pole
changing devices for transmitting electric currents, which are shewn in Figures 1,
2 and 12, but will be more readily understood by reference to Figure 5 which
shows an end view of the lever 57 in its normal or central position. When in this
position the lever 57 rests between two flexible resilient contact springs 67, and 69
which are mounted upon suitable standards 68 and 70 projecting from the base of
the apparatus. When the lever 57 is in its normal position of rest the circuit
springs 67 and 69 are both in contact with it, as shewn in Figure 5. The
standard 71 is yoke shaped at its upper extremity, and carries adjustable contact
screws 72 and 73. The contact screw 72 is so adjusted that when the end of the
lever 57 is depressed the spring 67 is brought into contact therewith and by the
same movement, the existing contact between the lever 57 and the spring 67 is
interrupted. In the same manner, when the lever 57 is clevated the spring 69
comes in contact with the screw 73 and at the same time breaks contact with the
lever 57.
The arrangement of the second main battery and second main circuit with
reference to the pole changing key last described will be best understood by
reference to Figures 5 and 12. The main battery 74 has its positive polo connected
by a wire 75, with the standard 71, and its negative pole in like manner connected
by a wire 76, with the key lever 57. The standart 68 is connected by a wire 77
with the earth and the standard 70. with the second line wire 78. extending to
the receiving station. By an inspection of Figures 5 and 12 it will be seen that
when the key lever 57 is in its normal position the line 78 is connected directly
with the earth through the standard 70, spring 69, key lever 57, spring 67,
standard 68, and wire 77. When the key lever 57 is elevated the positive or
copper current is sent to line, the circuitbeing as follows:-From the earth, through
the wire 77. standard, 68 spring 67, lever 57, wire 76, main battery 74, wire 75,
standard 71, contact screw 73, spring 69, and standard 70, to the line 78. When,
on the contrary, the key lever is depressed, a negative or zinc current is sent to
line, the route of which is as follows: from the earth to the wire 77 standard 68
spring 67, contact screw 72, standard 71, wire 75 main battery 74, wire 76, key
lever 57, spring 69, and standard 70, to the line wire 78.
The movements of the pole changing key 57 are controlled by means of the two
electro magnets 63 and 64 and a local battery operated by the keys of the key
board. The connections of this local battery will be understood by reference to
Figure 12. The local battery is shewn at 79, one of its poles being connected by
a wire 80, with the key-board wires 53, and 55 which are also a part of the main
circuit, and have already been described in that connection. The other pole of the
local battery 79 is connected by means of the wire 80 and the branch wires 81
and 82 with the electro magnets 63 and 64 which operate the herein-before described
pole-changing key. The electro magnet 64 is connected by means of a wire 83
with the metallic rack 45 in which the row or series of keys 42 is mounted. In

page_text: like manner the electro magnet 63 is connected by means of the wire 84 with the
metallic rack 47 in which the row of keys 44 is mounted. Hence if any one of
the keys in the row 42 (representing the letters of the alphabet) is depressed it not
only closes the shunt of the rheostat in the first main circuit as herein before
explained, but also closes the local circuit of the local battery 79 through the
electro magnet G4, the route of the current being from the battery 79 through the
wires 80 and 81, electro magnet 64, wire 83, rack 45, key 42, tooth of metallic
comb 46, and wires 55 and 80. In precisely the same manner if any key in the
row 44, (representing the numerals or other characters) is depressed, the circuit of
the local battery 79 is closed, through the electro magnet 63, the route being as
follows from the battery 79 by the wires 80 and 82, electro magnet 63, wire 84
rack 47, key 44 tooth of comb 48, and wires 53 and 80. The general effect pro-
duced by this organization therefore is that when any one key of the row 42 is
depressed a local circuit is completed from battery 79 through the electro magnet 64
and a positive current is thereby caused to pass over the second line wire 78, from
the second main battery 74, so long as the said key is depressed, and in like
manner when any key in the row 44 is depressed a negative current is sent over
the second line-wire from the same battery, and the polarity of the current thus
transmitted over the second line-wire, through the operation of mechanism herein-
after to be described, determines whether a letter or a numeral shall be printed
from the type wheel of the receiving instrument or a space or blank produced in
the printed record.
The means which I employ_for_maintaining-correspondence-between the trans-
mitting and receiving mechanism consists in the transmission of a single electric
impulse, always of the same polarity, once in each revolution of the traveller 41
which impulses pass over the second line wire to the receiving-station. This result
is effected by means of a rotating arm 85 fixed upon the shaft 25, which carries
the traveller 41. This arm is provided with a projecting bevelled pin 86 (best
seen in the detached view Figure 6) which pin at each revolution of the arm 85
comes in contact with a similar bevilled pin, 87 upon the key lever 57 when the
latter is in its normal position of rest, but not otherwise. The effect of this
arrangement is that once during each revolution of the shaft 25, just as the
traveller 41 passes the zero point, the pin 86 passes by and depresses the pin 87,
thus elevating the opposite end of the key lever 57 and sending a momentary
positive pulsation over the second line wire 78. It will be understood therefore,
that this positive pulsation of momentary duration is transmitted at one particular
point, that is to say the zero point in each revolution of the transmitting
apparatus.
The apparatus at the receiving-station which is employed for printing the
communications may, like the transmitting apparatus, bo conveniently regarded as
consisting of four sets of mechanism. The first of these produces or controls the
intermittent rotation of the type wheel axis and type wheel. The second produces
the impression of each character as required upon the paper and moves the latter
forward to the 'type wheel, in readiness for the next impression. The third deter-
mines the particular character of the impression whether it shall be a letter
numeral or space, and the fourth maintains the synchronism of the type wheel with
the transmitting-apparatus at the sending station and restores the type wheel to
its proper position in relation to the transmitter in case it is thrown out of
correspondence by accident or otherwise.
The first part of the receiving apparatus comprises a double type wheel (see
Figures 7, 8, 10, and 11,) which consists of two separate type wheels, 88 and 89
mounted side by side upon the same arbor 90. Each of these type-wheels contains
the same number of divisions-viz, twenty eight. The type wheel 88 has twenty
eight characters corresponding with those upon the twenty eight keys of the
key board 42 in Figure 4. The type wheel 89 has a similar set of characters
consisting of numerals &c. corresponding to those of the row of keys 44 upon
the key. board. Upon the type-wheel arbor 90 is fixed a scape wheel, 91 having

page_text: fourteen teeth. The type wheel and scape wheel tend to rotate continuously in
the direction indicated by the arrow in Figure 9 being impelled by a train of
wheel work 92 which receives its motion from a barrel 93 and cord 94 to which
a weight is attached. This mechanism may be wound up as required by applying
a suitable key to the winding post 95. The type wheels 88 and 89 are held in
check by a double acting anchor escapement, 96, the pallets of which engage
alternately with opposite teeth of the scape wheel 91. The escapement 96 is fixed
to a rock shaft 97, from which projects an arm 98 carrying the armature 99.
Two electro magnets 100. and 101 are arranged with their poles facing each other
upon opposite sides of the armature 99 as best seen in Figures 7 and 9. The yoke
or back armature of each of these electro magnets consists of a permanent magnet
of horse shoe form 102 and 102 into the opposite poles of which the respective
cores of the electro magnets 100 and 101 are inserted. Each permanent magnet
induces corresponding polarity in the respective cores of its attached electro-
magnet, and thus the latter are rendered in effect permanently magnetic while of
opposite polarity.
By reference to Figure 13 it will be seen that the north and south poles of the
permanent magnets 102, 102 (indicated by the letters n and s) are placed in such
relation to the cores of the electro magnets 100 and 101 that the respective similar
poles of the latter face each other upon opposite sides of the armature 99-that is
to say, two north poles face each other at one end and two south poles at the other
end of the same armature. The continuous conducting wire 18 which is included
in and forms a part of the first line wire is wound helically around these cores,
successively in the manner illustrated in the Figure. By tracing this wire in the
direction indicated by the arrows it will be observed that it is wound in one
direction around one core of the electro magnet 100 and in the opposite direction
around the other core of the same, after which it passes to that core of electro
magnet 101 whose like pole faces that of the last named core, and is wound around
it in the same direction; but its direction is again reversed in passing around the
other core of the electro magnet 101, so that its convolutions are now in the same
direction as those of the facing core of the other electro magnet. Thus it will be
understood that the conductor is wound in the same direction around the cores
whose like poles face each other and in opposite directions around the cores which
do not face each other. If therefore no current is passing through the wire 18,
the armature 99 will be attracted indifferently by either electro magnet 100 or
101; but if a current of one polarity is made to traverse the wire 18 the normal
magnetism in one of the electro magnets will be increased and that in the other
diminished, and the reverse effect will take place when a current of opposite
polarity traverses the circuit. Thus a positive current flowing in the direction
indicated by the arrows would tend to increase the normal magnetism existing in
the cores of the electro-magnet 100 and to diminish or destroy that in the electro
magnet 101, while a negative current would produce precisely the opposite effect.
Hence when alternate pulsations of positive and negative electricity are transmitted
through both electro magnets (these being included in the same circuit) the
armature 99 is caused to vibrate to and fro with great rapidity.
The printing mechanism consists of a lever 103 (see Figures 7 and 10) fixed
upon an arbor or shaft 104 which lever carries a cylindrical pad or platen 105,
and a paper-feeding mechanism 106, of the usual or of any suitable construction
by means of which a paper ribbon or tape 107 is drawn forward to receive the
impression of the successive characters from the type wheel, as required. The
paper feeding mechanism is actuated in a well known manner by the retrograde
movement of the printing lever 103 after the impression has been taken. The
electro magnet 108 actuates the printing lever, by direct magnetic attraction
exerted upon its armature 109 which armature is attached to the axis 104 of the
printing lever 103 as best seen in Figure 10.
The printing magnet 108 Figure 10, is included in the first main line circuit 18,
together with the magnets 100 and 101 Figure 9 which control the movements of

page_text: the type-wheels, and is brought into action, when required, by an increased
strength of current during the time of a single pulsation proceeding from the
transmitting station irrespective of its polarity. The printing mechanism is thus
actuated for the reason that the soft iron or neutral armature 109 responds equally
to either positive or negative currents, provided they are of sufficient strength.
The current of increased strength required for printing is transmitted from the
sending station by the short circuiting of the rheostat 52 at the transmitting
station through a key of the key board, in the manner hereinbefore explained.
The normal positive and negative pulsations traversing the first main line
although of sufficient strength, to oscillate the type wheel armature are quite
insufficient to actuate the printing mechanism. Hence the printing is effected by
simply increasing the strength of one of the pulsations whether positive or
negative at the instant the required character upon the type wheel is opposite the
platen and this is done as bereinbefore shewn without stopping the type wheel.
The mechanism which determines whether a given impression shall be taken
from one or the other of the two type wheels, or from neither of them when it is
necessary to produce a space, will now be described. The platen 105 consists of a
roller having a curved or convex face as best seen in Figures 11 and 11. This
platen is mounted in a frame 110 which is fixed upon a horizontal axis 111 which
axis is mounted in bearings 112 upon the lever 103 so as to admit of a horizontal
rocking, or oscillatory motion of the platen 105. The second main circuit 78,
coming from the transmitting station passes through the coils of an independent
electro-magnet, 112, (Figure 11) which is provided with a polarized armature 113
which latter is connected by a link 114 with a clutch lever 115 which moves
upon an axis 116. The clutch lever 115 is provided with two angular arms 117
and 118 which extend inwardly far enough to engage with one end or the other
as the case may be of the oscillating platen 105. If the clutch lever 115 is in its
central position as shewn in Figure 11 and the printing lever 103 is then actuated,
the platen 105 cannot come quite into contact with the type wheels, because it is
arrested by the projections 117 and 118 of the clutch 115; but the paper feeding
mechanism operates as usual upon the return of the platen and hence a space is
produced upon the paper. If the polarized armature 113 is deflected as indicated
by the dotted lines in Figure 11, the clutch 115 is moved to one side, as shewn by
dotted lines in Figure 11 and in the detached view Figure 11. Hence if the
printing lever 103 is actuated the platen 105 in moving toward the type wheels,
strikes against the projection 117 only and is tilted on its axis, so that its face
comes in contact with the type wheel 88, but not with the type wheel 89 as shewn
in Figure 11ª On the other hand, if the polarized armature 113 is deflected in
the opposite direction, the clutch lever 115 will be shifted and the impression will
be taken from the other type wheel 89 in the same manner. Thus it will be
understood that while the impression is produced by the action of the electro
magnet 108 the position of the polarized armature 113 determines whether that
impression shall be taken from the type wheel SS or S9, or from neither of them, and
consequently, whether the character printed shall be a letter, a numeral, or a space.
When no current whatever is passing through the electro magnet 112ª, which as
heretofore explained, is the normal condition of the second circuit, the central
position of the armature 113 is maintained by means of springs 120 and 121
mounted upon a standard 122. A pin 123 is inserted into the clutch lever 115
and plays between these two springs. The yielding of the respective springs
permits the lever to play in one direction or the other, according as the deflection
of armature 113 is produced by a positive or a negative current, and they restore
it to a central position when no current is passing. The double type wheel
supplied with ink, in the usual manner, by means of a suitable ink roller, 119.
In order to render it certain that the engraved letter upon the typ ewheel from
which the impression is to be taken shall be exactly opposite the platen when the
latter is brought into contact with it, so as to insure a clear and distinct impression
upon the paper, the type wheels 88 and 89 are not attached rigidly to the arbor 90,

page_text: but are mounted upon a sleeve 124, together with a toothed wheel 125. This
sleeve with its toothed wheel and type wheels is attached to the shaft by means
of a yielding spring 126.
Upon the printing lever 103 is fixed a corrector 127 which consists of a pro-
jecting arm or tooth, which engages with one tooth of the wheel 125 when the
printing lever rises, and holds the type-wheels in the proper position during the
instant that clapses while the impression is being made, even if the type wheel
axis 90 is moving forward at the same instant.
The unison mechanism comprises an arm 128 which is fixed upon the type-
wheel shaft 90 and revolves with it. A stop 129 projects from the upper corner
of the clutch-lever 115 into the path of the rotating arm 128, provided the clutch
lever 115 is in its normal-that is to say central position. Henco if the clutch lever
remained constantly in this position the stop 129 would arrest the motion of the,
arm 128 and consequently that of the type wheels also. So long however as the
transmitting and receiving instruments remain in correspondence the projection 129
is withdrawn from the path of the arm 128 at the proper moment by the action of
the electric pulsation which is transmitted once during each revolution of the
traveller 41, as hereinbefore explained, by the action of the arm 85 and bevelled
pin SG. If, however, the type wheels 88 and 89 are out of correspondence with
the traveller 41, the stop 129 will not be withdrawn from the path of the arm 128
at the moment of its arrival, and consequently the type wheels will be arrested
and held until the traveller arrives at the zero point in its next revolution, when
the transmission of the synchronizing pulsation will act upon the electro-magnet 112
and unlock the arm 128 permitting the type wheel to go forward. The instru-
ments at the transmitting and receiving stations may therefore be brought into
correspondence at any time when necessary by merely permitting the type wheels
to make one or more revolutions without printing.
The manner in which the apparatus is operated requires but little additional
explanation other than that which is contained in the description herein before
given. When the apparatus is to be used the shaft 25 is kept in continuous
rotation by the band passing around the pulley 27 and an uninterrupted succession
of alternate positive and negative pulsations is transmitted over the first main
line 18. These pulsations pass through the electro magnets 100 and 101 which
control the type wheels of the receiving instrument, and also through the electro-
magnet 108, which actuates the printing mechanism. The vibrating armature of
the electro magnets 100 and 101 permits the type wheel shaft 90 by the pro-
pelling force of the weight and the clock work, to revolve constantly in one
direction with a uniform rate of progression. The type wheels at the receiving-
station move synchronously with the traveller at the transmitting station and the
correspondence between the two is insured by the agency of the unison device,
which has already been described. When one of the keys upon the key-board is
depressed no effect is produced upon the first line wire until the traveller passes
over that segment of the sunflower which corresponds to the depressed key. When
this occurs however the rheostat 52 is momentarily cut out of the main circuit,
which increases the strength of the current sufficiently to actuate the printing
magnet 108 of the receiving instrument which attracts its armature momentarily
and thereby raises the platen 105 toward the type wheels 89 and 88. If the key
depressed be one of the first row, representing a letter of the alphabet, a positive
current is sent over the second wire during the time it is so depressed, which acts
upon the polarized armature 113 of the electromagnet 112 and causes the platen
to be tilted, as in Figure 11ª so as to print a letter from the type wheel 88
whereas if a key in the third row is depressed a negative current is transmitted
and a numeral is printed from the type wheel 89. If any one of the middle row of
keys is depressed no current is transmitted over the second inain circuit. Hence
the armature 113 remains in its central position and the platen 105 is prevented
from coming in contact with either of the type wheels, and a blank or space
accordingly appears upon the paper.

page_text: The improved apparatus is capable of transmitting communications with much
greater rapidity, that is to say, of printing a much greater number of characters
in a given time or by means of a given number of pulsations-than those
heretofore in use. This result is partly due to the method which is employed of
printing from the type wheel without interrupting or retarding its progressive
movement, and partly to the circumstance that a space may be printed during any
portion of the revolution of the type wheel and without reference to its position,
instead of a single point only in each revolution. Under ordinary circumstances at
least one space is required in every four or five letters. Hence it is obvious that
an important saving of time is effected by inserting the space or blank in the
printed record immediately after the last letter of any given word, and during
that portion of the revolution of the type wheel which takes place after the last
letter of one word has been printed and prior to the printing of the first letter of
the next succeeding word.
It is to be understood that any required number of independent printing
instruments at the same or different receiving stations may be included in the
circuit of the same pair of main line wires and actuated simultaneously by a single
key board and transmitting apparatus constructed and operated in the manner
herein before set forth.
Having thus described 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
claim.
First. The combination of a main lino, a main battery a series of insulated
metallic segments, a series of branch conductors, one of which is electrically
connected-with-each-of-said-segments, a series of finger keys for establishing
electrical connection between the main line and any one of said branches at the
will of the operator, a traveller and mechanism for causing the same to pass over
and make electrical contact successively with each segment in the series an
artificial resistance included in the circuit of said main line, and a branch conductor
connecting the traveller with the main line, whereby the said resistance is cut out
of the main circuit by the traveller while passing over the segment corresponding
to the particular key which is depressed.
Second. The combination of a main line, a main battery a series of insulated
metallic segments, a traveller and means for causing the same to pass successively
over each segment in the series, a pole changer mechanically connected with the
axis of said traveller or reversing the poles of the main battery with reference to
the line when the traveller passes from one segment to the next succeeding one, a
series of keys, each key of which is connected with one of said segments, and a
rheostat included in said main line, which is cut out by the traveller while passing
over the segment corresponding to the particular key which is depressed.
Third. The combination of a series of insulated metallic segments, a traveller
and means for causing the same to pass over and make contact successively with
each segment of the series, a main line extending to the distant station, a main
battery, a traveller, a pole changer, whereby the polarity of the battery with
reference to the main line is reversed when the traveller passes from one of the
segments of the series to the next succeeding one, a rotating arm rigidly connected
with the traveller, a key lever momentarily actuated by said rotating arm at the
same point in each successive revolution, a main line extending to the distant
station, and a second main battery which is connected with said line by said
key lever when the latter is momentarily actuated by the rotating arm.
Fourth. The combination of a key board having its keys arranged in three rows,
a main battery, a main line extending to the distant station, a local battery two
electro magnets, a conductor connecting said magnets with the key board and
including said local battery, and a key lever actuated by said key board and
capable of being placed in three positions, of which the first position connects the
positive and the second the negative pole of the main battery to the line, while the
third disconnects the battery from the line.

page_text: Fifth. The combination of two rigidly united type wheels, a platen mechanism
substantially such as described for causing said platen to oscillate so as to print
from one or the other of said type-wheels, an electro-magnet for impelling said
platen toward the type wheels, and an independent electro magnet for controlling
the lateral movement of the oscillating platen.
Sixth. The combination of two rigidly united type-wheels a platen mechanism
substantially such as described for causing said platen to oscillate so as to print
froin one or the other of said type wheels, an electro magnet for impelling said
platen toward the type wheel, a polarized armature for controlling the lateral
movement of the oscillating platen, and an independent electro-magnet for actuating
said polarized armature.
Seventh. The combination of two rigidlyunited type wheels a laterally oscillating
platen having a convex or curved face and mechanism substantially such as
described for controlling the lateral oscillation of said platen.
Eighth. The combination of two rigidly united type wheels a platen capable
of three positions mechanism substantially such as described for oscillating said
platen and an armature for controlling the lateral oscillation of the platen
which is capable of three positions corresponding to the respective positions of the
platen.
Ninth. The combination of two rigidly united type wheels, a laterally oscillating
platen, and a elutch lever substantially such as described for controlling the
lateral position of the oscillating platen with reference to the plane of the type-
wheels.
Tenth. The combination of a type-wheel or type wheels, a platen a paper
feeding mechanism actuated by the mechanism which moves the platen and
mechanism substantially such as described for arresting the movement of the
platen, whereby the paper feed may be actuated at any point in the revolution
of the type wheel without bringing the platen into contact with said type wheel.
Eleventh. The combination of a type-wheel or type-wheels, a platen, mechanism
for impelling said platen toward the type wheel or type-wheels a clutch and
mechanism substantially such as described for interposing said clutch between
the platen and the type wheel or type wheels, whereby the movement of the
platen may be arrested and its contact with the type wheel or type wheels
prevented.
Twelfth. The combination of a type wheel axis a sleeve mounted upon said axis,
a type-wheel or type-wheels and a toothed wheel rigidly mounted upon said sleeve,
a yielding mechanical connection between said sleeve and the type wheel axis, a
platen and a corrector or projection rigidly affixed to the printing-lever for locking
the type-wheel or type wheels by engaging with said toothed wheel while the
platen remains in contact with the type wheel.
Thirteenth. The combination of a type wheel axis, a rotating unison stop fixed
upon said axis, a clutch lever, a pin on said clutch lever, normally projecting into
the path of the rotating unison stop, an electro magnet for actuating said clutch
lever and withdrawing said pin from the path of the unison stop, a rotating arm
upon the transmitting axis and a key for transmitting a momentary current
through said electro magnet once during each revolution of the transmitter and
typewheel axis when said key is actuated by said rotating arm.
In witness whereof I the said Sydney Pitt have hereunto set my hand and
seal this Twenty seventh day of June in the year of our Lord One
thousand eight hundred and eighty two.