An Improved Indicator for Marking the Position and Variable Motions of Steering Gear and other Moving Apparatus.
Year: 1892

page_text: Date of Application, 14th Mar., 1892
Complete Specification Left, 14th Dec., 1892-Accepted, 4th Feb., 1893
PROVISIONAL SPECIFICATION.
An Improved Indicator for Marking the Position and Variable
Motions of Steering Gear and other Moving Apparatus.
We WILLIAM ERNEST GRAY and WILLIAM ARTHUR PRICE, both of
Silvertown in the County of Essex, Electricians, do hereby declare the nature
of this invention to be as follows:-
This invention relates to improved means for indicating, by the aid of electricity,
the positions taken up by a ship's rudder, a float, or a lever, and thereby avoiding
the misunderstanding of orders conveyed to the attendant, whether a steersman or
otherwise.
Mounted on an indicator board, is a central shaft carrying on one side of the board
an index hand, and on the other a cog wheel. Into the teeth of this wheel, and at
opposite sides thereof, take two pairs of pawls, which are carried by two vertical
bars, capable of sliding freely in bracket guides attached to the back of the
indicator board.
Projecting from each of these bars, is an arm which carries a solenoid core or
armature, and in line with each of these cores is a hollow electro magnet made fast
to brackets on the board. The wires from these magnets connect with the steering
or other apparatus, the movements of which are intended to be indicated, and
it is by the movements of such apparatus that the battery circuit for energising
the electro-magnets is made and broken.
The sliding bars have a limited vertical motion between stops, they being raised
by the attraction of their respective electro-magnets, and dropping by their own
weight when the circuit is broken. The pawls of each pair are held in contact,
as required, with the toothed wheel by a coupling spring, and rest pins are provided
on the sliding bars for taking the locking pawls out of action. Stop pins are also
provided for arresting the motion of the driving pawls, when they have advanced
the wheel the distance of one tooth. These movements of the pawls are effected as
their respective sliding bars are lifted or dropped. The rise of the one sliding bar
causes the toothed wheel to be advanced a tooth in one direction, and the rise of the
other bar gives an opposite movement to the toothed wheel. These varying
movements are presented to view by the indicator hand, which, travelling over a
dial on the indicator board, shews the position taken up by the rudder, float, or
lever.
The form of magnet which we prefer to employ in this apparatus, is a pendent
hollow cylinder of iron, containing a coil of wire, through the centre of which
depends a brass tube, which forms a guide for the armature carried by the sliding
bar. The cylinder is closed at top and bottom by discs of iron, a central opening
being made in the lower disc, for the passage upwards of the armature, which is
preferably a light tube of iron closed at top."
Dated this 14th day of March 1899
NEWTON & SON,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
An Improved Indicator for Marking the Position and Variable
Motions of Steering Gear and other Moving Apparatus.
We WILLIAM ERNEST GRAY aud WILLIAM ARTHUR PRICE, both of
Silvertown in the County of Essex, Electricians, 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 fellowing statement :-
This invention relates to improved means for indicating, by the aid of electricity,
the positions taken up by a ship's rudder, a float in a reservoir or tank, or, it
may be, a lever connected with distant apparatus, the movements of which are
required to be noted.
In the accompanying drawings,
Fig. 1 shews in elevation our improved indicating apparatus, the back of the case
being removed to show the arrangement of the mechanism for moving, by pulsations,
an index hand over a graduated dial; and
Fig. 2 is a vertical central section of the same.
In applying this indicator to a ship, for shewing the movements and positions of
the rudder, it is fixed on the bridge, and it is connected to a transmitting apparatus
to receive electric pulsations therefrom, in the manner to be hereafter described.
AA is a metal case provided to receive the indicator, and furnished with a glass
face which presents the dial to view, also with three terminals B, B', B', those
marked B and B₁ being in electrical connection with the transmitting instrument,
and B with the battery.
C is the dial plate, graduated in any approved manner, according to the use to
which the indicator is to be applied.
For marine purposes, the dial plate will be divided to correspond to the compass
card, but the divisions for indicating the movements of a float would represent
inches and feet.
D is a central shaft for carrying the index hand D¹. It has its bearings in the
dial plate C, and in a back plate C¹ made fast thereto.
Upon this central shaft D, a toothed wheel D' is fitted. Into the teeth of this
wheel, and at opposite sides thereof, take two pairs of pawls, marked respectively
ff and ff, which are carried respectively by vertical bars F F. These bars
are free to slide in bracket guides attached to the back of the dial plate C.
Projecting from each of these bars, is an arm which carries a solenoid core or
armature gg, and in line with these cores are the hollow electro magnets GG*,
made fast to brackets on the back of the dial plate. The coils of these magnets
connect respectively with the terminals B and B¹, and they have, in common,
connection with the return wire B2, which leads to the battery, or it may be to
earth.
The sliding bars have a limited vertical motion between stops 1, 1, they being
raised by the attraction of their respective electro magnets, and dropping by the
aid of springs F¹, in the case of the marine indicator, or by their own weight when
the circuit is broken. The pawls of each pair are held in contact, as required, with
the toothed wheel, by coupling springs Rest pins 2, 2, are provided on the
sliding bars F F, for holding the pendent locking pawls out of contact with the
teeth of the wheel D³, on the rising of their respective bars. The driving
pawls ffare provided with rest pins 3, 3, for retaining the pawls in a position for
acting. They are also provided with stop pins 4, 4, for arresting their motion,
when the wheel has been advanced the distance of one tooth.
The rise of the sliding bar F, under the attraction of its magnet G, causes the
toothed wheel to be advanced a tooth in one direction, and the rise of the bar F*
gives an opposite movement to the toothed wheel. It is the result of these varying
movements, caused by the change in direction of the electric current passed
4

page_text: through the indicator, which it is desired to present to view on the dial by the
indicator hand, as representing the position taken up the rudder, float, or lever, as
the case may be.
The form of magnet which we prefer to employ in this apparatus, is shown in the
section Fig. 2, and consists of a pendent hollow cylinder of iron containing a coil of
wire, through the centre of which depends a brass tube, forming a guide for the
armature carried by the sliding bar F. The cylinder is closed at top and bottom
by discs of iron, a central opening being made in the lower disc, for the passage
upwards of the armature, which is preferably a light tube of iron closed at top.
The electromagnets G, G*, are energised by electrical currents transmitted from
apparatus with which the indicator is connected through its terminals, such
apparatus being itself connected with the moving part whose motion is to be
indicated. The transmitting apparatus employed in connection with our indicator,
may be made in several ways, but in every case it will contain a contact-making
piece suitable for sending an electrical current of short duration, whenever the
moving part, whose motion is to be indicated, passes one of a series of points at
equal distances from one another. Thus, if the moving part be a float in a reservoir,
the contact-making piece may be put in action whenever the float comes to one of
a series of positions distant, say, one inch apart. Or, if the moving part be a
tiller, the contact-making piece may be put in action whenever the tiller comes to
one of a series of positions one degree of angular measurement apart.
The transmitting apparatus is also arranged so that the currents are passed into
one or other of the electromagnets of the indicator, according as the moving part
whose motion is to be indicated, moves in one direction or the opposite. Thus, if
the moving part be a float, the currents are passed through one electro magnet, if
the float be rising, and through the other, if it be falling This may be done in one
of two ways. The first way is to use two wires connecting the transmitting to the
receiving apparatus, with a common return. One wire is connected to one electro
magnet, and the other to the other, and the currents are sent by the transmitter
along one wire, if the moving part whose motion is to be indicated is moving in
one direction, and along the other if it is moving in the opposite direction.
The second way is to use one wire only with a return, and to arrange the trans-
mitting apparatus so that positive currents are sent when the moving part, say, the
tiller, moves in one direction, and negative currents, when it moves in the other.
In this case, means are employed in connection with the indicating instrument for
passing positive currents through one electro magnet, and negative currents through
the other.
The construction of apparatus for attaining this result is well understood, and
need not here be described.
Referring now to Fig. 1, and assuming that the transmitting instrument above
referred to is coupled up with the terminals B B', it will be understood from the
foregoing description, that when the electro magnet G is excited on the completion
of the circuit, it will lift the bar F to the dotted position, and at the same time
cause the driving pawlf to move round the wheel D' the distance of one tooth.
On the electric circuit being broken by the continued movement of, say, the
tiller, over its contact-making piece, the attraction of the magnet will cease, and
the frame F with its driving and locking pawl will fall from the dotted to the drawn
position. The further movement of the tiller will re-establish the current, and the
like action of the driving pawl will be repeated, and so on for any given number
of times, or until the movement of the tiller is reversed, the index hand on the
shaft D making a corresponding movement over the graduated dial.
On the reversal of the tiller's movement, the electro magnet G* will, in its turn,
become excited, and, by attracting the armature of the bar F*, will cause the
pawl to drive round the wheel D³, to the left, the distance of one tooth, which
action will be repeated at every breaking and making of the current, through the
movement of the tiller in the reverse direction, the index hand in like manner
giving the corresponding indications on the dial,

page_text: From the foregoing explanation, it will be readily understood how the rise and
fall of a float will mark its changes of position on the dial, and how indications of
the varying movements, say, of distant mechanism, may be brought within the
cognizance of an inspector of the indicator.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
The improved indicator above described with reference to the drawings, in which
the movements of the index hand are controlled by a pair of electro-magnets
excited by intermittent currents transmitted by the varying movements of an
instrument connected to the moving part, (such as a tiller or a float), whose positions
it is designed to follow on the dial of the indicator.
Dated this 14th day of December 1892.
NEWTON & SUN,
Agents for the Applicants.