Improvements in Electrical Signalling Apparatus for Marine Purposes.
Year: 1895

page_text: Date of Application, 3rd Apr., 1895-Accepted, 11th May, 1895
[Communicated from abroad by BRADLEY ALLAN FISKE, of the "Beresford,"
New York City, United States of America, Lieutenant, United States Navy.]
Improvements in Electrical Signalling Apparatus for Marine
Purposes.
1, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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:-
The invention is an electrical signalling system for marine use.
It is an
apparatus whereby from a given station, an order may be. sent to a distant point,
and whereby, through the mechanical execution of said order, a knowledge that
the same has been obeyed will be transmitted back to the main station.
In the accompanying drawing which shows a diagrammatic view of the invention
A and B represent two arcs of conducting material. C is a movable contact
piece touching the arc A, and travelling along the curved guide D. E is a movable
contact piece touching the arc B and travelling along the curved guide F. G and
H are fixed contact pieces at the middle points of the arcs A and B. I and J are
galvanometers having identically-marked dial plates, showing angles in degrees.
The circuits are as follows:
From battery or dynamo at K, to the terminals a a¹ of are A by wires c c¹, and
also to the terminals bb of arc B by wires d d¹.
'
From contact piece C by wire e to one terminal of galvanometer J, and by
wire e from the other terminal of galvanometer J to fixed contact G.
From contact piece E by wire to one terminal of galvanometer I, and by
wire f¹ from the other terminal of galvanometer I to fixed contact H.
The operation is as follows:
The operator at the arc A moves the contact piece C toward or from the
fixed contact piece G on either side thereof. Therefore he throws into the
circuit K, c, a, C, e¹, galvanometer J, e, G, a', , K, (which I will call eignalling
circuit) a greater or less length of the arc A, and hence varies the fall of potential
between the terminals of galvanometer J, which indicates this fall by the movement
of its index-needle, say to point 30 degrees on its scale.
The operator at the are B, having the movable contact piece E, say, originally
coinciding, with the fixed contact piece H and hence bearing on the middle point
of arc B, moves said contact piece over the distance indicated by the needle of
galvanometer J and in the direction shown; that is, in the drawing; a distance
of 30 degrees to the left. When he does this he will have thrown into the
circuit K, d, b, E, f, galvanometer I, f', H, b', d', K, (which I will call indicating
circuit), exactly the same length of arc, and hence have caused therein the same
drop in potential as the operator A had previously caused in the signalling circuit,
and he will bave moved his contact piece E in the same direction as the
observer at A has moved contact piece G. Therefore the galvanometer I will
show the same deflection in the same direction as galvanometer J.
Generally stated, there must be such a definite physical relation between the
arcs A and B as that a movement of the contact piece C for a certain distance
over arc A shall cause a deflection of the needle of galvanometer J to a certain

page_text: mark on its scale, and that a corresponding movement of the contact piece over
arc B shall cause a deflection of the needle of galvanometer I to a like mark on
its scale. So long as this relation exists the actual proportions of the arcs are
immaterial, and the precise relation of the distances on them thrown into circuit
becomes immaterial.
The galvanometers I J will be marked " port" and "starboard," as shown, on
opposite sides of the datum point, and the scale, on each side of that point, will be
laid off in a suitable number of degrees of arc. The arc A with its contacts C G,
and the galvanometer I will be located on the bridge, or at any other convenient
place from which it is desired to control the helm.
The arc B, with its contacts E and H, will be placed in such suitable proximity
to the rudder of the vessel as that the latter, by any, suitable mechanism, may move
the contact E over the are B; the disposition of parts being such that the angle of
inclination of the rudder from its midship position will be indicated by the position
of the contact piece E on one side or the other of the fixed contact piece H. The
galvanometer J, is placed at the helm in convenient sight of the helmsman.
The battery K is situated in any convenient location.
Let it now. be supposed that the person controlling the vessel desires to direct
the helmsman to place his helm 30 degrees to port.
With his hand he moves the
contact Cover arc A. a distance to the left from the point G as will cause the
needle of the galvanometer J, as already explained, to point to the mark of
30 degrees to port on its scale. The helmsman seeing this indication of the
galvanometer J, manipulates the steering apparatus to place the rudder as directed;
and the movement of the rudder causes the contact piece E to travel over the
arc B for such a distance as to cause the needle of galvanometer I to point likewise
to the mark 30 to port.
Consequently the person sending the order is notified first that it has been obeyed,
second, that it has been obeyed correctly, third, the instant that it is obeyed, and
fourth, the exact position of the rudder at all times; and this by instrumentalities
which the helmsman cannot control except by exactly complying with the
directions sent him.
"
An especial advantage of this arrangement is the safe-guard which it offers
against failure of the apparatus to work, or improper working in case of accident.
If for instance, the signalling circuit be broken, the needle of the galvanometer J
at once returns to the datum point and thus the helmsman is directed to "steady
his helm or in other words, to keep the vessel in the course in which she is moving.
Hence the moment the operator at A signals a direction to change the course, he
will perceive, by the immobility of his own galvanometer needle, that it is not
obeyed, and the impairment of the apparatus is immediately revealed.
If, on the other hand, the indicating circuit is injured, that fact will be instantly
shown upon the first use of the signalling circuit, for, while the helmsman obeys
the order, the operator's galvanometer nevertheless fails to indicate the new position
of the rudder.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. A signalling and helm indicating apparatus for marine use having (1) the
elongated conductors A and B in circuit, (2) fixed contacts G and H thereon, and
(3) contacts C and E movable respectively on each side of said contacts G and H,
and (4) indicating instruments 1 and J, and (5) circuit connections: and operated
by first, moving at a transmitting station, à contact () over conductor ▲ for a
certain distance to one side or the other of the contact G, thereby actuating
instrument J at the distant station to give a deflection corresponding in direction
to the direction of movement of said contact and in extent to the difference of
potential caused between its terminals, thus conveying an order of direction and
angle of helm: second moving the helm of said vessel as directed by said deflection

page_text: and thereby simultaneously moving a contact E, over conductor B for a definite
distance on one side or the other of contact H and thus actuating an instrument [
to repeat the indication of instrument J.
Dated this 3rd day of April 1895.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.