Improvements in Apparatus for Transmitting Telegraphic, Indicating, or other Analogous Signals or Movements.
Year: 1888

page_text: Date of Application, 23rd Oct., 1888
Complete Specification Left, 19th July, 1889-Accepted, 7th Sept., 1889
Improvements in Apparatus for Transmitting Telegraphic, Indicating,
or other Analogous Signals or Movements.
1, ANDREW BETTS BROWN, of Rosebank Iron Works, Edinburgh, in the-County
of Mid Lothian North Britain, Engineer, do hereby declare the nature of this Inven-
tion to be as follows, that is to say :-
My said Invention relates to telegraphing, indicating, and other analogous apparatus
in which signals, or movements are transmitted through a greater or less distance
by means of chains, cords, wires, rods, or similar mechanism; and it has for its
object to apply to such apparatus devices for ensuring the accurate correspondence of
the sending and receiving instruments.
In the simple case taken for example, in which the movements are transmitted by
means of an endless chain passing round pulleys at the sending and receiving stations, an
index fixed to the receiving pulley ought always to correspond in position with an
index or hand lever fixed or connected to the sending pulley, but owing to slackening
of the chain or other cause, the parts are, in practice, apt to get out of correspondence
and then the receiving instrument does not give indications precisely agreeing with
the signals or movements intended to be transinitted.
In such apparatus the parts have frequently to be in or pass through their middle
positions, and in carrying out my Invention a correcting device is arranged to operate
at such times. One or more springs or weights or an equivalent appliance is arranged
to act on the receiving pulley in a manner to move it to its middle position whenever
it is let go after being moved therefrom in either direction. The sending pulley is
connected to the hand lever or part by which it is moved so as to become disengaged
therefrom whenever such actuating part is moved into its middle position. The
sending pulley and transmitting chain are then free to move; and if the receiving
pulley is not then in correspondence, that is, in its middle position, the springs or
parts acting on it move it at once into its middle position. When the next signal
or movement has to be transmitted the hand lever on being moved from its middle
position instantly engages with the sending pulley and makes it act on the transmitting
chain, and the sending hand lever and the receiving pulley and index start in exact
correspondence.
It is necessary for the transmitting chain or equivalent to preserve as uniform a
state of tension as possible, and for any slack occuring to be at once taken up. For
this purpose a tension pulley acted on by a weight or spring is applied, and is
prevented from oscillating with the variations in the tension caused by transmitting
signals or movements, by means of a ratchet-toothed bar with which a pawl or
catch engages. The catch prevents movement of the tension pulley in the slackening
direction but secures it in whatever position it assumes in taking up slack.
1000
EDMUND HUNT,
Applicant's Agent:
COMPLETE SPECIFICATION.
Improvements in Apparatus for Transmitting Telegraphic, Indicating,
or other Analogous Signals or Movements.
I, ANDREW BETTS BROWN, of Rosebank Iron Works, Edinburgh, in the County of
Mid Lothian, North Britain, Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement, that is to say :-
My said Invention relates to telegraphic, indicating, and other analogous apparatus

page_text: in which signals or movements are transmitted through a greater or less distance by
means of chains, wires, cords, or similar mechanism; and it has for its object to
apply to such apparatus devices for insuring the accurate correspondence of the
sending and receiving instruments.
In the simple case, taken for example, in which the movements are transmitted by
means of an endless chain passing round pulleys at the sending and receiving
stations, an index fixed to the receiving pulley ought always to correspond in position
with an index or land lever fixed or connected to the sending pulley; but owing to
the slackening of the chain or other cause, the parts are in practice, apt to get out
of correspondence, and then the receiving instrument does not give indications
precisely agreeing with the signals or movements intended to be transmitted.
In such apparatus the parts have frequently to be in or pass through their middle
positions, and in carrying out my Invention a correcting device is arranged to operate
at such times. One or more springs or weights or an equivalent appliance is arranged
to act on the receiving pulley in a manner to move it to its middle position whenever
it is let go after being moved therefrom in either direction. The sending pulley is
connected to the hand lever or part by which it is moved, so as to become disengaged
therefrom whenever such actuating part is moved into.its middle position. The
sending pulley and transmitting chain are then free to move; and if the receiving
pulley is not then in correspondence, that is, in its middle position the springs or
parts acting on it move it at once into its middle position. When the next signal or
movement has to be transmitted, the hand lever on being moved from its middle
position instantly engages with the sending pulley and makes it act on the transmitting
chain, and the sending hand lever and the receiving pulley and index start in exact
correspondence.
On an accompanying sheet of explanatory drawings are shown by way of example,
a few of the various arrangements which may be adopted in which the sending
pulley is free when the hand lever is in its middle position but is engaged with and
moved by that lever whenever it is turned from the middle position in either
direction. An arrangement is also shown for moving the receiving pulley to it middle
position when it is free to be so moved.
Figure, 1, of the drawings is a sectional elevation of the sending instrument of a
ship's engine telegraph; and figures, 2, and 3, are horizontal and vertical sections
of one modification of the engaging devices. A second modification of the engaging
devices is shown in vertical section in figure, 4; and a third modification is shown
in figures, 5, and 6, which are vertical sections' as at right angles to each other.
Figure, 7, is a vertical section showing the receiving pulley and parts for centering
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
it.
In the modification shown in figures, 1, 2, and 3, the sending hand lever, A, is
fixed on a spindle, B, passing through and fitted to turn in the dial or front plate, C,
and in the back of the casing, D. Inside the casing there is fixed on the spindle, B,
a piece made with two arms, E, to which are jointed weighted pawls, F, provided
to engage with teeth on a wheel, G, fixed to or made in the same piece with the
sending pulley, H, which is loose on the spindle, B. The pawls, F, are made with
arms, J, which are formed with slots engaging on a pin projecting from the inner
side of a spindle, K; and this spindle, is guided in a socket formed in the boss of the
arms, E, and is made with a collar to compress a helical spring, L, which surrounds
it. The outer end of the spindle, K, is made with an angular point; and in the
casing there is fixed an angular point, M, placed so as to be encountered by the
spindle, K, when the hand lever, A, is moved into its middle position, and then
having the effect of pushing in the spindle, K, and thereby taking the pawls, F, out
of gear and setting the sending pulley, H, free to turn independently of the hand
lever. The parts fixed on the spindle, B, are counterbalanced by a weight, N.
In the modification shown in figure, 4, which a section as viewed from the back
of the instrument, the pawls, F, are connected by toothed sectors and their arms, J,
are arranged to be acted on directly by a cam piece, M, fixed in the casing, D.

page_text: In the modification shown in figures, 5, and 6, a bolt, P, acted on by a spring, L,
and carried by a piece, Q, fixed on the spindle, B, is arranged to engage with the
toothed wheel, G, but is pushed out of gear when the band lever, A, is moved into
its middle position by a cain ring, R, formed or fixed on the inside of the front plate, C,
this cam acting on an arm projecting forwards from the bolt, P, through a slot in
the piece, Q.
In the receiving instrument (figure, 7) the receiving pulley, S, is fast on a
spindle, T, which has fast on it the usual external index (not shown) and also a
pinion, U, which gears with a toothed sector, V, centered on a pin fixed in the
casing. The sector, V, has jointed to it two rods, W, which have collars arranged
to compress springs, X, in boxes hinged to the casing; and these springs move
the sector, V, and through it the receiving pulley, S, to the middle position whenever
the sending pulley, H, is set free by the moving of the sending hand lever, A,
into its middle position.
It is necessary for the transmitting chain, cord, or equivalent, Y, figures, 1,
and 7, to preserve as uniform a state of tension as possible, and for any slack
occurring to be at once taken up. For this purpose a tension pulley, Z, figure, 1,
acted on by a weight or spring, 8, is applied, and is prevented from oscillating
with the variations in the tension caused by transmitting signals or movements, by
means of a ratchet-toothed bar, 9, with which one or more pawls or catches, 10,
engage. The catches, 10, prevent movement of the tension pulley, Z, in the
slackening direction, but secures it in whatever position it assumes in taking up slack..
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
In apparatus for transmitting telegraphic, indicating, or other analogous signals
or movements by means of chains, cords, wires, rods or similar mechanism, such
mechanism being acted on by means of pulleys or equivalent devices and acting on
pulleys or equivalent devices, applying springs or weights to act on the receiving
parts and place them in exact correspondence with the transmitting parts whenever
the latter are moved into or through the middle or other predetermined position, the
transmitting parts being provided with a cam or other device which disengages the
actuating parts so as to allow of the correcting adjustment, all substantially as herein-
before described.
Dated this Eighteenth day of July 1889.
EDMUND HUNT,
Applicant's Agent.