IMPROVEMENTS IN PRINTING TELEGRAPHIC APPARATUS, AND IN THE ÅBRANGEMENT OF THE CIRCUITS TO BE USED IN CONNECTION THEREWITH
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Charles Adams Randall at the
Office of the Commissioners of Patents, with his Petition, on the
12th November 1872.-Partly a communication from abroad by
Theodore Marshall Foote, of New York.
I, CHARLES ADAMS RANDALL, of the City, County, and State of New
York, United States of America, and at present of Great Portland
Street, in the County of Middlesex, do hereby declare.the nature of the
said Invention for "IMPROVEMENTS IN PRINTING TELEGRAPHIC APPARATUS, AND
IN THE ÅBRANGEMENT OF THE CIRCUITS TO BE USED IN CONNECTION THEREWITH," to
be as follows :—
This Invention relates to that class of telegraph instruments known as
reporting instruments, and to an automatic transmitting apparatus, and
also to the arrangement of circuits to be used in connection with the
same.
The improvements in the recording instrument consist :—
1st. In mechanism for changing or shifting a single type wheel on
its shaft so that it may be changed by the sending operator, and made

page_text: to print either figures or letters at will. For this purpose the type
wheel is provided with two sets of characters arranged alternately, and
to enable the said wheel to be changed so as to cause it to print with
the one or the other set of characters it is made to shift on its shaft,
and is connected to fixed arms thereon by jointed rods, whereby it is
moved sufficiently to cause the one or the other set of characters to be
brought into position for printing as the type wheel is rotated, the said
connections serving also to lock the wheel in the one or the other
position on the shaft.
2ndly. In the combination of said mechanism with the printing lever
or any part connected thereto, whereby to effect directly by the action of
the printing magnet or the printing current the said change of the type
wheel, a key or keys being provided in the transmitter for the purpose,
the change being made by the movement of the printing lever when
the type wheel is in a certain position.
3rdly. In the construction of the propelment or mechanism to produce
the rotation of the type wheel. The type wheel shaft carries two ratchet
wheels actuated alternately by pallets or pawla jointed to the opposite
extremities of a rock lever, connected to and operated by the electrically
polarized armature of the type wheel magnets herein-after referred to.
4thly. In the combination with a type wheel capable of being so
changed or shifted upon its shaft of an automatic unison or stop for
arresting the type wheel, and so bringing the receiving instrument into
unison with any other instruments in the same circuit.
The improvement in the transmitting instrument consists in so
arranging the lettered keys of an automatic current transmitter, that
the manipulation of said keys and of the printing key (when a special
current to print is employed) may be easily and rapidly accomplished
with one hand. For this purpose the keyboard is arranged in a circular
form, having in the centre an extra key, the depression of which effects
the transmission of the current for printing.
The Invention further consists in the arrangement of the batteries
and circuits in such a manner that a current passing over a circuit may
pass through a helix or a number of helices, thereby charging or
polarizing one or more soft iron armatures with a known polarity (and
thus dispensing with the use of a permanent steel magnet), and by
sending a current from another battery, or an extra power over the

page_text: same wire, the printing magnets in said circuit may be charged, and
the printing from the wheel effected, thereby attaining two results with
the one wire.
In combination with the electrically polarized armature are electro-
magnets in a circuit, over which reversed currents are caused to pass,
by which combination and the herein-before described mechanism the
rotation of the type wheel is effected.
By another arrangement of circuits and batteries a common soft iron
non-polarized armature is employed, vibrating between the two type
wheel magnets, and currents are caused to pass alternately through the
type wheel magnets, and one helix of the printing magnets for rotating
the type wheel, the printing being effected by a current passing
simultaneously over both circuits, using both wires as a metallic circuit
or with earths.