Improvements in Printing Telegraphs.
Year: 1889

page_text: Date of Application, 27th May, 1889-Accepted, 29th June, 1889
AARDEN
Improvements in Printing Telegraphs.
1, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents,
do hereby declare the nature of this invention (a communication to me from abroad
by William Francis Johnson, of 242 Purchase Street, Boston, in the County of
Suffolk, and State of Massachusetts, United States of America, Merchant) 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 the class of printing telegraph receivers in which two
series of characters are printed by means of two type wheels arranged to rotate in
different planes.
The object of this invention is to provide means by which a greater certainty in
the action of the escapement and unison mechanism may be secured and in which
delicate adjusting and liability to get out of repair will be avoided.
The Invention consists in the combination with the unison and escapement
magnets of a permanent magnet common to both the unison and escapement magnets
for polarizing the armatures of the said magnets, thus increasing the sensibility of
the said magnets and rendering them more positive in their action.
The Invention also consists in the combination with the tape-feeding mechanism,
of devices for checking the feeding roller to prevent too great a consumption of the
tape and to ensure a proper spacing of the letters and characters.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which figure 1 is a side elevation of the improved printing telegraph
receiver; Figure 2 is a rear elevation; Figure 3 is a rear sectional elevation ;
Figure 4 is a plan view, partly in section, of the scape wheels and their shafts j
Figure 5 is a horizontal section taken on line x-figure 1; and figure 6 is a detail
rear elevation of the feed mechanism. Similar letters of reference indicate
corresponding parts in all the views.
In describing this improved printing telegraph receiver, it will be unnecessary to
enter into the description of the mechanism by which the message is transmitted, it
being sufficient to describe the character and direction of the current passing through
the magnets of the machine.
The Invention will be described in connection with a machine operated by two
line wires, but some portions of the invention are equally applicable to machines
operated by a single line wire.
The frame A which supports all the parts of the mechanism of this improved
printing telegraph receiver is formed of the side frames a a¹ connected by the cross-
bars 6 6 6. In the downwardly-projecting arms c c¹ of the frame A are journaled
the two driving shafts d d¹ to which are secured the drums e e¹ and upon which are
loosely placed the spur wheels ffl. The drums e e¹ are provided with ratchets g_g'.
which are engaged by dogs h / pivoted to the wheels ff and adapted to engage the
ratchets g g', the said dogs being pressed into engagement with the said ratchets by
the springs attached to the wheels ff. In one side of the frame A are journaled
the shafts j, k, l, and in a similar manner upon the opposite side of the frame are
journalled the shafts j¹. Upon the shaft j is placed a pinion m which is engaged
by the spur wheel f and upon the same shaft is mounted a spur wheel n which engages a
pinion o on the shaft k. Upon the shaft k is mounted a spur
which
P
engages
wheel T, the office of
a pinion g on the shaft 1, and the shaft also carries a spur
which will presently be described. In a similar manner the spur wheel 1 engages a
pinion m' on the shaft j and the said shaft carries a spur wheel n' which engages a
pinion o¹ on the shaft k, the said shaft carrying a spur wheel p which meshes into
a pinion g' on the shaft P. The shaft / carries a spur wheel r, the use of which will
wheel

page_text: presently be described. To bring the gearing thus described within the compass of
the frame A, the shafts d d' and the drums and wheels mounted thereon, together
with the gearing driven by the respective shafts are oppositely arranged with respect
to each other. Upon the drums e el is wound a cable s upon which rests a sheave t
carrying the hook u, the said hook being adapted to receive a weight for
driving the two trains of gearing. In a bracket attached to the side frame a¹ is
journalled a tubular shaft B which is provided with a pinion C which is engaged by
the spur wheel r². Upon the outer end of the tubular shaft B is placed the type
wheel D and upon the said shaft between the pinion and the outer arm of the
bracket vis placed the unison arm E. Upon the inner end of the said tubular shaft B is
secured the scape wheel F. In the tubular shaft B and in supports a² 62 projecting
from the frame A is journaled the shaft G. To the inner end of the shaft G is
attached a pinion H which is engaged by the spur wheel r and to the said shaft G
between the pinion H and the scape wheel F is secured a scape wheel I. In the side
of the said scape wheel I is inserted a stud c² which is engaged by the unison
mechanism presently to be described. On the outer end of the shaft G is placed the
type wheel J in close proximity to the type wheel J. It will thus be seen the two
scape wheels I F are arranged in close proximity to each other and that they are
capable of being driven independently in the same direction by the two sets of gearing
already described.
c²
To the top of the frame A is secured the permanent magnet K having one of its
poles d² at the top of the frame while the other pole e² projects horizontally inward
toward the centre of the machine and is provided with a concave face f2. In an
arm g² placed between the inwardly-turned end of the magnet K and the upper end
of the said frame A is journalled a vertical spindle L, the upper end of which turns
in a screw h² inserted in the central part of the magnet K. Upon the spindle L
opposite to, and near, the concave face 2 of the magnet K is placed an armature 2 and
between the armature and the pole d² of the magnet K is placed an electro-magnet M
which is supported by screws passing through the end of the magnet K. The polar
extremities of the magnet M are opposite and near the armature so that when the
said magnet is energised, it is capable of acting upon the armature. To the end of
the spindle L which is prolonged below the arm g² is secured an escapement pallet N
which is capable of engaging either of the scape wheels I, F. The escapement
pallet N is of the usual form, but is arranged to vibrate in a plane at right angles to
the plane of rotation of the scape wheels. By this arrangement a single pallet is able
to control the movement of both of the scape wheels. In the upper part of the
frame A is journaled a rock shaft O which extends across the frame and carries two
arms, the said arms being provided with right angled ends for stopping the
scape wheels. The arm ² is capable of engaging the pins projecting from the face
of the scape wheel I and the arm 12 is capable of engaging the arm E carried by the
tubular shaft B. To the end of the shaft O which projects through the side frame a
is attached a forked arm m² which engages a finger n² carried by the armature o²
which is pivoted to the pole d² of the magnet K. To the side frame a is attached
the yoke p² of the magnet P, the poles q² q of the said magnet being arranged
opposite each other and upon opposite sides of the armature o². The said armature o
is polarized by contact with the end d² of the magnet K. To the bar 62 of the
frame A is adjustably secured the printing magnet R which is further held by
guides attached to the sides of the said frame A and in the frame is journalled a
rock shaft S carrying an armature lever 2 which supports an armature t2 within the
field of the printing magnet R. To the rock shaft S outside of the frame A is
attached the printing lever T formed of the boss u², the side arms and the cross
bars w². In the lever T is journalled the guide roller a³ and the printing roller 63.
The arm 3 is prolonged beyond the printing roller 63 and carries a spring actuated
pawl which engages the ratchet d³ attached to the feeding roller e³. A spring
detent secured to the side of the frame A prevents the ratchet d³ from retrograde
motion but the said spring detent f³ does not prevent the ratchet from being thrown
forward by a quick movement of the lever T.

page_text: In machines of this character, as ordinarily constructed, no provision is made for
preventing the forward movement of the feed roller e3 beyond the prescribed limit,
and in such machines the consumption of tape is much greater than is required for the
printing done by the machine. To avoid the undue forward motion of the feed roller,
I apply to the arm v3 of the printing lever T an auxiliary detent g³ which strikes into
the space between two adjacent ratchet teeth and arrests the motion of the said ratchet
as soon as the pawl c³ has moved the ratchet one notch and thus prevents the ratchet d³
from moving more than one notch at a time. The roller e³ is provided with a serrated
wheel ³ for engaging the paper guided through the machine by the said roller. In
the face of the side frame a is inserted a stud 13 which supports an angled lever m³
carrying upon one of its arms a wheel n³ which is arranged opposite the serrated
wheel. The other arm of the lever m³ carries a stud which is engaged by a
spring på secured to the edge of the frame the said spring being arranged to tilt the
lever m³ and thus bring the wheel n³ into contact with the paper tape which passes
over the roller e and the serrated wheel k³. The printing lever T is drawn downward
after each action of the magnet R by a spiral spring h³ having one end attached to
the said printing lever while the other end is connected with the thread ³ wound
around a windlass 3 which adjusts the tension of the said spring. The motion of the
printing lever Tis limited by the screws q³ ³ arranged above and below the prolongation
of the arm 3 of the printing lever. To the front of the frame A is secured an arm s³
which extends downwardly between the type wheels D, J, and prevents the paper tape
from adhering to the said wheels. To the arm 3 which supports the feeding roller e³
is attached a guide u³ for retaining the paper tape in the proper position in its passage
through the machine. To the same arm t³ is also attached a wire guide v* for guiding
the paper tape. To the cross-bar b is attached an insulating block at provided with
binding posts 6 for receiving the line wire which is connected with the printing
magnet R and the unison or shifting magnet P. To the cross-bar bis attached an
insulating piece which is provided with binding posts d for receiving the line wire,
the said binding posts being connected electrically with the magnet M. The frame A
is provided with right-angled notches e which are fitted to a suitable support for the
machine and upon the hook u is placed sufficient weight to drive the two trains of the
machine, the cord s being arranged with reference to the two trains so that they are
both driven in the same direction and produce motion in the same direction in both the
scape wheels 1, F. The type wheels D, J, are supplied with ink from felt rollers f* f
carried by the arms arranged to turn upon studs h4 h projecting from the
frame A, the said felt rollers resting by their own gravity upon the peripheries of the
said type wheels. The drums e e¹ are wound by a key placed on the squared portion
of their shafts in the usual manner, the amount of winding upon each drum being
limited by a stop motion i³.
The operation of the improved printing telegraph receiver is as follows:--when an
alternating current is sent through the line wire connected with the magnet M, the
armature is oscillated, imparting a corresponding movement to the segmental
pallet N which acts upon one or the other scape wheel I F, allowing it to move forward
with a step by step motion. One of the scape wheels I F, is always locked by its
arm k² or 2 and the wheel which is locked by the said arm cannot move until it is
released in the manner presently to be described. The other wheel moves forward
until the proper letter, figure, or character, is brought to the point of printing by the
motive power of the train. When the current through the escapement magnet ceases,
the scape wheel operated by the magnet, stops and the current is sent through the
printing magnet R, thus bringing up the printing lever carrying the paper tape into
contact with the type wheels and producing the impression of the desired letter, figure,
or character. The wheel not in use, being locked and immovable, exposes a blank
space at the point of printing, so that no printing takes place upon that wheel. So
long as the current through the printing magnet is sent in the same direction, no
shifting of the scape wheels or type wheels will take place, but when it is desired to
shift from one type wheel to the other, the current through the printing magnet and
through the unison or shifting magnet P, which is in the same direction is reversed,

page_text: thereby shifting the position of the polarized armature o² consequently tilting the
lever m³, rocking the shaft O unlocking the type wheel which has been inactive and
locking the one which has been in use thereby permitting the escapement pallet to
act upon that scape wheel. The type wheel which was before inactive, now rotates
upon the oscillation of the segmental pallet and the printing is effected as before.
This wheel continues in action until the current is again reversed in the circuit of the
printing magnet R and in the shifting or unison magnet P.
Whenever the printing lever T after being carried up to produce an impression is
released by the printing magnet R, the downward movement of the said lever turns the
ratchet d³ one notch in the manner already described and feeds the paper forward to
receive a new character. When it is desired to move the paper without printing, both
the type wheels are brought to zero and the current is sent through the printing
magnet only, thereby causing the printing lever to oscillate and operate the feed
roller e without producing any impression upon the paper..
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a printing telegraph receiver, the combination with two scape wheels arranged
to rotate in parallel planes, of an escapement pallet common to both scape wheels,
arranged to oscillate in a plane at right angles to the planes of the scape wheels and a
magnet adapted to oscillate the escapement pallet, substantially as specified.
2. In a printing telegraph receiver, the combination with a pair of scape wheels
arranged to rotate in parallel planes, of type wheels connected with the scape
wheels, a pallet common to both scape wheels arranged to oscillate in a plane at right
angles to the planes of the scape wheels, a spindle carrying the pallet, an armature
attached to the spindle, an electro-magnet arranged to oscillate the polarized armature,
shifting mechanism for stopping one scape wheel and releasing the other, an electro-
magnet for operating the shifting mechanism, and a permanent polarizing magnet
common to the pallet operating armature and the armature of the shifting mechanism,
substantially as specified.
3. In a printing telegraph receiver, the combination with the scape wheels and scape
wheel shafts, of stop arms or pins connected with the said shafts or wheels, a rock
shaft provided with arins for engaging the said stop arms or pins, and a shifting
magnet for operating the rock shaft for locking one of the scape wheels and
releasing the other, substantially as specified.
4. In a printing telegraph receiver, the combination of two independently operated
scape wheels controlled by a single escapement pallet, a magnet placed in a line
circuit furnished with a polarized armature, and adapted to oscillate the escapement
pallet by means of an alternating current, printing mechanism operated by a second
line circuit, and shifting mechanism adapted to be operated by reversals of the current
in the printing circuit, substantially as specified.
5. In a printing telegraph receiver, the combination of two scape wheels arranged
in parallel planes, of a pallet common to both scape wheels, two type wheels connected
with the scape wheels and arranged to operate independently of each other, and a
printing lever adapted to carry the paper tape into contact with either of the type
wheels, substantially as specified.
6. In a printing telegraph receiver, the combination with the printing lever, of a
feed roller provided with a ratchet, a pawl carried by the printing lever and adapted
to act on the ratchet of the feed roller, a detent for preventing retrograde motion of
the feed roller, and an auxilliary detent attached to the printing frame for limiting
the forward throw of the feed roll, substantially as specified.
7. In a printing telegraph receiver, the combination of two trains of motor gearing,
two scape wheels propelled independently of each other by the motor gearing,
two type wheels operated by the scape wheels, a pallet common to both scape
wheels, a polarized armature, and a magnet for operating the pallet, a rock shaft
provided with arms for arresting the motion of one or other of the scape wheels,

page_text: a shifting electro magnet and polarized armature for operating the rock shaft, a
polarizing magnet common to the pallet operating armature and the armature of
the shifting magnet and the printing and paper feeding mechanism, substantially
as specified.
8. In a printing telegraph receiver the combination with the type wheels, of a
pair of inking rollers one to each type wheel arranged to press by their own
gravity on the type wheel, substantially as specified.
9. In a printing telegraph receiver the combination with the type wheels and the
printing lever, of a finger attached to the frame of the instrument and extending
between the wheels and downwardly below the periphery of the wheels for preventing
the adherence of the paper tape to the type wheels, substantially as specified.
10. In a printing telegraph receiver the combination with the printing and feeding
mechanism, of a paper tape guide, substantially as specified.
Dated this 27th day or may
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.