Improvements in Telegraph Transmitters.
Year: 1886

page_text: Improvements in Telegraph Transmitters.
I GEORGE WASHINGTON BALDRIGE, Stenographer of the City of St Louis, State
of Missouri, United States of America 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, reference being had
to the accompanying drawings forming part of this Specification, and in which :-
Figure 1 is a top or plan view of my improved instrument.
Figure 2 is a side view showing one of the disks partly broken away.
Figure 3 is a detail vertical section of the apparatus.
Figure 4 is a perspective view of one of the disks looking at its face.
Figures 5 and 6 are perspective views of one of the arms; Figure 6 being an
outside and Figure 5 an inside view.
Figures 7. 8 and 9 are views of the recorder or register.
My Invention relates to certain improvements in mechanical telegraph trans-
mitters, and my invention consists in features of novelty herein after fully described
and pointed out in the claims.
Referring to the drawings A represents the base of the apparatus, to which are
secured standards B. B¹; those B having brackets or projections C, in which is
journalled a shaft D carrying disks I and being turned by means of any suitable.
motive power. I have not shown any means for turning it, as any well known
motor may be employed.
On the periphery or rim of each disk is a letter, figure or character, which may
be duplicated or triplicated, if desired,-that is to say, there is a disk for each letter,
figure and character, and this letter, figure or character may be made twice or more
times on the disk. I have shown them duplicated. In one side of each disc,
behind or back of the letter, figure or character, is a groove J adapted to receive a
pin L on an arm M, pivoted or hinged on a rod or arbor N supported by brackets O
formed upon or secured to the standards B, or it may be supported by any other
suitable means. The pins L are either non-conductors or else the arms are
isolated at O¹
By this arrangement, no matter when a letter is struck, the pin rides on the
outer rim of the disk holding the contact spring free of the type until the
revolution of the disk brings the forward end of the slot opposite the pin, when
the latter enters, thereby allowing the contact spring to strike the type only at the
forward part.
The pin continuing in the slot until the letter is completed.
This is (to illustrate) for the reason that as the telegraphic letter P is composed
of five dots, if the contact spring was allowed to descend say upon the second dot,
the remaining number. (4) would produce the letter H upon the wire. Therefore

page_text: .
the groove performs a double duty-the outer rim allows the contact spring or
brush V to touch the type only at the forward end and the inner rim acts as a stop
against the spring M
There is an arm for each disk and each arm has an upward extension M¹.
P represents the keys supported on a rod or arbor T fitting in the upper ends of
the standards B. On the front or inner ends of the keys are the finger pieces P¹
and their back or outer ends have notches P2 to receive the extensions of the arms.
When the keys are operated and the arms moved inward by the springs M², and
their extensions moved outward, the parts P' of the keys rest upon the ends of the
extensions of the arms, as shown in Figures 4 and 5 thus keeping the finger pieces
of the keys depressed until the letter is completed and the pin moved outward by
the dog and the extension of the arm again moved back to the position shown in
Figure 2, and then the finger piece will rise, thereby indicating to the operator by
sight the completion of the letter.
The outer ends of the keys are held down by suitable springs P³, and the lower
ends of the arms are forced or pulled inward toward the disks, when released by
the springs M². I have shown a rod U supported by the brackets O, to which the
outer ends of these springs M³ may be made fast. The lower ends of the springs P³
are made fast to a rod Ui
Secured to each arm is a brush or spring V (which can be made adjustable) the
free end of which bears or rides upon the periphery of the disk opposite it, while
the pin L of its arm is in the groove J of its disk (see Figure 5) to close the circuit
between the battery wire W and line wire X. As the pin reaches the end of the
groove it comes against a spring dog I¹ to throw the lower end of the arm out into
the position shown in Figure 2, to remove the spring or brush from the disk and
open the circuit, and the arm is held back until the key is again operated, as will
be understood when I explain the operation of the machine.
The dogs are pivoted to the disks by screws I* around which are coiled the
springs I made fast at one end to the disks and bearing by their other ends against
the dogs.
The electricity passes (see Figure 1) from the battery (not shown) through the
wire W to the shaft D and disks I and then to the brushes or springs V, arms M,
rod N, and out along the line wire X which is secured to the rod N as shown at N¹
Figure 1. The disks are conductors and have non-conductors I³ secured in their
peripheries to form the spaces of the letters, figures or characters or if preferred, the
disks could be non-conductors and the parts I conductors; but in this case, the
parts I would of course make the dots and dashes, of the letters, figures and
characters, and a wire or other connection would have to be made between them
and sleeves on the shaft D.
This arrangement is more particularly intended for adaptation to a polarized
circuit in which that which produces breaks in a straight circuit reverses the
polarity (but does not break the circuit), by being conducting material but
connected, as shown, with the opposite pole of the battery.
One pole is used for the dots and dashes composing the signal and the other pole
for producing the spaces.
The rods N, T and U are isolated from their supports.
Y represents the spacer-key and Y¹ its finger-bar, supported by an idle bar Y
at one end,
The spacer-key operates a peculiar type such as n and m run together. This is
to be used to indicate the completion of a word instead of a space or interval,
when sending to a mechanical receiver; the transcribing operator writing as one
word, the letters or characters found between any two of these space-signals.
Each disc preferably has a short hub I on one side by which they (the discs)
are held a short distance apart on the shaft D.
The operation is as follows:
The shaft D is first set in motion to turn the discs in the direction indicated by
the arrow, Figure 3. As soon as the key is struck its outer end will be raised

page_text: releasing its arm M, as shown in Figure 3, permitting the pin L to be brought
against its disc by the spring M³ and as soon as the groove J comes to the pin;
by the turning of the disc, the pin will enter it permitting the brush or spring to
come against the periphery of the disc (see Figure 3), and close the circuit, sending
the letter, figure or character on the disc, as above mentioned.
As the pin
approaches the ends of the groove, it comes against the spring dog I' and forces it
back against a shoulder 1' of the disc and the dog then forces the pin, arm and
brush out to the position shown in Figure 3, out of contact with the disc, and in
doing this it forces the extension M¹ of the arm inward past the notch P* of the
finger, and the spring P³ will then pull the finger down, which will hold the arm
in this position until it (the key) is again operated.
As soon as the dog has passed the pin, its free end is moved back to its inner or
normal position by the spring Is where it does not project beyond the face of the
disc, and consequently will not touch the pin again until that key is again operated
and the pin passes through the groove J.
By duplicating or triplicating the letters, figures or characters, and the grooves
and dogs on the discs, the machine is made to operate more quickly, as the pin L
will not have so far to ride on the disc, after the key is touched before entering
a groove.
W10 represents the lever for making and breaking the current of the wire W.
On my transmitter may be used any ordinary receiver or register to receive a
message from a transmitter located at another place. I have shown an ordinary
Morse receiver W", the construction of which is well known and needs no
description. W12 represents the moveable gear-wheel of the shaft D carrying the
discs I. The wheel is forced out of engagement with the wheel W13, as usual with
this form of register, by the arm W₁ (see Figures 7, 8 and 9), the free end of
which fits in a screw W15 of the shaft D and, when the arm is raised by the
armature being pulled down upon the magnets, the wheel is forced back by the
spring W16, as usual.
The receiver or register is not intended, or at least need not be connected
electrically to the transmitter, to which it is secured (its principal use being, as
stated, to receive a message sent from another transmitter located in another place),
but it may be so connected to the transmitter to which it is secured by a wire Wir
(see Figure 2), so that the message sent by this transmitter will be registered by
this receiver.
The only novel feature I claim in connection with this register, is applying it to
the disc shaft of my transmitter.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is :-
1. In a telegraph transmitter, a disk carrying letters, figures or characters and
having a way behind the letters, figures or characters, in combination with an arm
carrying a contact brush and a pin or projection, the parts being so arranged that
the pin or projection will traverse said way while the contact brush is bearing
against the letters, figures or characters, substantially as set forth.
2. A telegraph transmitter having the telegraphic letters, figures or characters
formed upon revolving disks and having suitable means for closing and breaking
the circuit to transmit the letters figures or characters and spring dogs secured to
said discs for throwing the circuit after the transmission of a character, substantially
as set forth.
3. A telegraph transmitter having the telegraphic letters figures or characters
formed upon revolving disks and having suitable moveable contact brushes or
members arranged opposite said disks and adapted to be forced into contact
there with to transmit the letter, figure or character, the disks having grooves and
dogs behind the letters, figures or characters, the grooves being adapted to receive
and hold said brushes or members against the letters figures or characters and the

page_text: dogs being adapted to force said brushes or members out of contact with the
letters, figures or characters substantially as set forth.
4. In a telegraph transmitter, the discs supported and turned by suitable means
and provided with telegraphic letters, figures or characters, back of which are
grooves to receive pins or projections on arms controlled by the keys of the
instrument and having brushes for coming in contact with the letters figures or
characters substantially as specified.
5. In a telegraphic transmitter the discs supported and turned by suitable
means and provided with letters figures or characters, back of which are grooves
and spring dogs the grooves being adapted to receive pins and projections on arms
controlled by the keys of the instrument, and having brushes or springs for coming
in contact with the discs to close the circuit, and the dogs being adapted to throw
the arms and brushes out from the discs to open the circuit, substantially as set
forth.
6. In a telegraph transmitter, the revolving discs having letters, figures or
characters, and grooves, in combination with spring dogs secured to the discs, arms
having extensions, springs acting to move the lower ends of the arms inward, keys
with notches to engage the extensions on the arms, pins or projections on the
arms to enter the grooves in the discs and brushes or springs secured to the arms
and adapted to bear against the discs on the letters, figures or characters, sub-
stantially as and for the purpose set forth.
7. In a telegraph transmitter, the discs secured to a revolving shaft and having
letters, figures or characters, in combination with spring-dogs secured to the discs,
arms supported on a rod, and having extensions, springs acting to move the lower
ends of the arms inward when the keys are operated, keys supported on a rod and
having notches to engage the extension of the arms, spring to pull the outer ends
of the keys down, pins or projections on the arms to enter the grooves in the discs
and brushes or springs secured to the arms and. adapted to bear against the discs
on the letters figures or characters, substantially as and for the purpose set forth.
8. In a telegraph transmitter, the combination of the type-discs, insulated arms
having extensions, springs and dogs for operating the arms and keys adapted to
bear against the extensions of the arms while the letter, figure or character is
being formed to hold the finger piece depressed, the dogs acting to move the arms
and extensions to permit the finger-keys to rise, substantially as and for the
purpose set forth.
9. In a telegraph transmitter, in combination with keys having finger pieces
and transmitting discs, each carrying the sign of a letter, figure or character, arms
pivoted to the stationary frame carrying brushes for contacting with said trans-
mitting disc and adapted to lock the keys until a letter figure or character is
transmitted, and means for actuating said arms, so as to lock the keys and bring
the brushes and discs into contact.
10. In combination with the shaft carrying discs, a receiver or register applied
or connected to the said shaft, substantially as and for the purpose set forth.