IMPROVEMENTS IN ELECTRIC TELEGRAPHS
Year: 1885

page_text: I HENRY CHRISTOPHER MANCE of 143 Manor Road Brockley in the county
of Kent Civil Engineer do hereby declare the nature of my Invention for
IMPROVEMENTS IN ELECTRIC TELEGRAPHS and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
The object of the invention is to improve the apparatus for translation of
Telegraphic signals automatically between two circuits (cables or land line) when
relays of an extremely sensitive or unstable character are employed-although
designed more especially to meet the requirements of the Brown Allan Relay
my improvements can be worked in connection with other relays and telegraph
apparatus.
The general arrangement of the connections for Automatic Translation would
be substantially similar to that of other systems of double current Translation and
will be understood-The improvements consist of a clockwork with suitable
mechanism and contacts contrived and arranged as shewn in the drawings and
hereafter described to obviate the difficulty caused by the uncertain character of
very sensitive relays which sometimes come to rest with the local circuit open and
sometimes with it closed-this difficulty is well understood by Electricians.
I shall now proceed to describe the essential parts of the apparatus.
I require as part of the mechanism two knee pieces or catches or pieces of metal
bent at an angle and arranged in connection with an Electro Magnet so that one
end of each can be struck by the armature at every beat that is to say the end of
one catch is struck at every depression of the armature and the end of the other at
every return of the armature to its normal position-the effect being that the
upper ends of the angle pieces are at every blow struck from under the weighted
end of a lever in the clockwork which I call the starting lever. The end of this
lever can be supported by either of the angle pieces so that to ensure the weighted
end dropping there must be an up and down motion of the armature so as to strike
both angle pieces clear-The upper end of the angle piece acted on by the up
motion of the armature is a trifle shorter than the upper end of the other angle
piece which is struck out when the armature of the Electro magnet is attracted.
Now assume the armature of the Electro Magnet attracted-the longer angle
piece is struck from under the weighted end of the starting lever and the latter
falls about one thirtieth of an inch being then supported by the shorter 'angle
piece-Should there be no further motion of the armature of the Electro-magnet
(which may be that of a Morse printer or sounder) the starting lever does not fall→
the contact lever or translation switch (to be hereafter described) is not disturbed→

page_text: there is no movement in the clockwork but if the armature rises (which would
occur every time the local circuit opened) the second angle piece would be struck
from under the end of the starting lever and the latter would no longer be
prevented from falling.
It will therefore be understood that before the starting lever can drop there
must be an up and down movement of the armature so as to strike both knee
pieces clear of the end of the lever.
One function of the starting lever is to raise directly or indirectly the weight or
catch or brake which pressing against the fly wheel (or its equivalent) of the
clockwork prevents its running-a fall of the starting lever therefore starts the
clockwork.
While the clockwork is running the starting lever is continuously lifted by a
projecting pin or eccentric wheel at intervals of about three seconds so that the
angle pieces can pass under its extreme end and support it-Should however the
armature continue working the angle pieces are again struck clear and the starting
lever falls again immediately.
A second function of the starting lever is to move in its fall the Translation
switch lever (which is connected to line) from the Relay contact to the Translation
Battery contact-The Translation switch remains in contact with the sending
Batteries during the whole time of signalling and for about three seconds after the
signalling ceases after which interval the weight which acts as a brake is allowed
by an eccentric in the clockwork to fall stopping the clockwork and at the same
time releasing the Translation switch and allowing it to return by two steps to its
normal position in contact with the relay.
During such time as the Translation lever is switched to the Translation sending
batteries the local batteries of the opposite instrument are placed on short circuit
by means of suitably arranged additional contacts on the Translation switch-The
armature therefore of the opposite instrument remains immoveable notwith-
standing any movement which may take place accidentally in the opposite relay.
The Translation switch returns to its normal position by two steps-this is
arranged in the following manner-A small disc with two notches is fixed on the
axis of the translation switch-When the switch is first depressed by the fall of
the starting lever a small tongue or spring passes into the second notch holding the
switch firmly in position during the whole time the clockwork is running and the
translation is going on-When the clock work is about to stop the eccentric wheel
in the clockwork allows the brake to fall a short distance and press on the small
tongue or spring just sufficiently to clear it from the second notch-The Trans-
lation switch then rises half way when it is arrested by the small tongue catching
in the first notch-in this position the line is connected for an appreciable period
with earth the end of the switch in its middle position resting on an earth
contact-Meanwhile the eccentric allows the brake to fall still further pressing the
tongue or spring out of the first notch, the switch then returns to its normal
position and the brake falling on the fly wheel stops the clock work.
It is immaterial whether the local circuit of the Electro Magnet (acted on by the
relay) remains open or closed or sometimes one and sometimes the other after
sending terminates-What is required is that the translation switch should leave
the battery contacts-make temporary contact with earth to clear the line of
current and then rejoin line to relay at the same time setting free the locals of the
opposite instrument this takes place whenever the clockwork stops and this
stoppage of the clockwork ensues as already explained whenever the armature of
the Electro Magnet remains motionless for a few seconds either in the up or down
position.
It is important that while the Relay and armature of one instrument is working
the translation switch of that instrument controls the Electro Magnet of the
opposite instrument so as to prevent any alteration in the position of the opposite
switch this ensures that the incoming current shall not be cut off by any
accidental movement in the opposite relay.

page_text: The outgoing Translation currents may be sent to line from the screws or points
limiting the play of the armatures of the Electro magnet attached to the clockworks
or a detached Electro magnet may be used.
The armature can be used if required as a sounder or ink writer by the ordinary
contrivances.
DESCRIPTION OF DRAWINGS.
It will be seen that while the armature B of the clockwork works in an
up and down motion the clockwork continues to run-The small angle pieces or
catches F F are being continuously struck by the screws E, E and the starting
lever G is never permitted to permanently assume its normal position-The action
of the brake O which stops the clockwork is therefore suspended either by the
pressure of an eccentric wheel in the clockwork or the weight of the starting
lever When the latter was first allowed to drop by the movement of the sounder
armature B it depressed the weighted lever K and also the line translation switch I
thereby taking the pressure off the brake O and starting the clockwork meanwhile
connecting the line to the transmitter at S-The Translation switch lever is
retained in its depressed position by a catch N. M. which can only be acted on by
the weighted lever K. When the working of the armature ceases the starting
lever G is raised by a pin on the eccentric which revolves every three or four
seconds and remains at its highest position supported by F or F1 the latter catches
being no longer disturbed by the movement of the armature-The weighted end
of the lever K. (regulated by the eccentric wheel drops a short distance thereby
acting on the tongue or spring which liberates the Translation switch and allows
the weighted end of the latter to fall and the contact making end to rise to the
extent of one notch or step that is to say to its midway position where it is
arrested by the tongue or spring pressing into another notch-thus holding the
extremity of the Translation switch in contact with an Earth terminal R for an
appreciable time.
"
On the catch tongue or spring being again acted on by the lever (the dropping
of which is regulated by the eccentric) the contact making end of the Translation
switch I rises another step to its normal position making contact with the opposite
relay and at the same time the pressure of the weighted end of the Line Lever or
Translation switch on the Brake O or the pressure of the weighted lever K as may
be arranged stops the clockwork.
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
An improved combination and regulation of contact pieces levers and eccentric
dise substantially as described and as shewn in the drawings actuated by an
Electro Magnet and clockwork for automatically switching during translation
working first, the opposite line to the signalling batteries or transmitter secondly
the line to Earth for a short period and thirdly the line back to the opposite relay
for receiving-The Translation Switch remaining motionless in each position to
ensure perfect contact and the necessary switching taking place at the commence-
ment and cessation of signalling altogether irrespective of the position in which
the tongue of either relay or the armature of either Electro Magnet may come
to rest.