Improvements in and relating to Electric Ship Logs and Speed Indicators.
Year: 1894

page_text: Date of Application, 10th, Oct., 1994
Complete Specification 'left. 9th July, 1895-Accepted, 28th Sept., 1895
PROVISIONAL SPECIFICATIỤN.
Improvements in and relating to Electric Ship Logs and Speed
Indicators.
".
WILLIAM DAVID WHYTE Nautical Instrument Maker 144 Broomielaw Street
Glasgow, and DAVID MUIRITEAD Engineer 244 Cumberland' Street Glasgow,
do hereby declare the nature of this invention to be as follows:-
This invention is for the purpose of ascertaining the distance run by ships at sea,
also the speed at any given moment, by means of an electro mechanical indicator
which may be placed either on the bridge, or in the wheel house, or other suitable
place.
The indicator is constructed as follows:
:-
An electro magnet is attached to a brass seat & attached to the magnet is the
usual iron armature, on the loose end of the armature is fixed a pawl, or clutch,
then a steel spindle with a worm on the centre, and a ratchet wheel at the end, this
is fixed on the brass seat on a parallel line a short distance from the armature
supported by two upright sockets, so that it will revolve freely, & placed in position
so that the pawl or clutch will grip the teeth of the ratchet wheel.
The pawl is pressed on the ratchet wheel by means of a small steel spring, so
that when the armature is moved towards the magnet the pawl pulls round the
ratchet wheel one tooth and causes the spindle to revolve slightly.
Fixed into the worm is a pinion wheel placed in an upright position so that when
the spindle revolves the worm causes the pinion wheel to revolve and indicates by
means of a hand fixed on the end of the pinion the miles, or parts of miles
on a dial.
Revolving with this pinion wheel is a brass arm about one inch long, and at
a suitably placed position is another pinion wheel with suitable number of teeth
so constructed that when the brass arm makes one complete revolution the arm
comes in contact with this large pinion wheel, and moves it round one tooth
which indicates by a smaller hand on the, dial fifty miles, that is to say one
revolution of the first pinión wheel with suitable number of teeth will register
fifty miles, and nt the same time press round the second pinion wheel which
will register fifty miles, the arm on the first pinion wheel disengages itself from
the second pinion wheel, and continues to register the miles, and parts of miles
from one to fifty, and the second pinion. wheel from fifty to two thousand, or
more as may be required.
In cases where. a very large mileage is required we prefere doing away with
the chronograph movement for registering the fifty miles on the small dial, and
substatuting this arrangement.
A worm is arranged on the centre, spindle, and geared into a pinion wheel, which
wheel is again geared to another worm, and fits into a toothed wheel, which indicates
on a small dial the total mileage.
The whole movement is fitted in a brass casc, so that it can be hung up
anywhere,
The second combination of improvements are connected with the propeller,
break, and contact mechanism.
A propeller is fitted into a frame shaped, so as to allow it to rotate freely inside,
it is resting on a bearing pin, or rollers at the bottom of the frame, and fits by
means of a shaft into a water tight bush at the top, and then passes into a

page_text: water tight chamber, and connects itself to a worm, into which is fixed a wheel with
teeth constructed to fit into the worm, so that when the propeller revolves it turns
this worm, and so causes the wheel to revolve, conected to this wheel is a pin on
the under side, when this wheel has made one revolution the pin comes in contact
with another wheel, so constructed that the pin fits into one of the teeth, or spokes,
and causes this wheel to revolve until the piu disengages itself.
This wheel is fixed on a shaft which passes through a bulk head, (which
separates another chamber) where the break, and contact springs are placed, on
the other end of this shaft (in the second chamber) is fixed in a suitable position a
pin, or spoke, which when one revolution has been made by the shaft it presses
against a spring, and causes it to touch another spring, both of these springs being
the two poles of an electrical battery are conected, and so causes the circuit of
electricity to become complete, and pulls the armature on the magnet in the
indicator, (bichis conected by wires in the usual way) and causes it to make the
motion which indicates the part, or parts of a mile as already described. This
frame with the propeller, and contact, and break mechanism in two water tight
compartments is towed after the ship either from the side, or from behind in the
usual way.
in it n
In some cases we prefer to have the contact, and break mechanism separated
from the propeller by simply doing away with the frame, and having the case
containing the contact, and break mechanism on the taffrail, and connects the shaft
to a rope with the propeller at the other end, and towed after the ship in the usual.
way.
The insulated wires are conected from the mechanism on the taffrail to the
indicator on the bridge, or other place. The electric force is generated in a number
of Laclanche batteries, conected in the usual
-
way.
When the springs are released by the pin disengageing itself from them, the
current ceasing, the armature in the indicator springs back, and, is ready, for
the next contact.
1717
When the frame with the propeller complete is towed along side the ship, it is
so attached to the cable that it lies at an angle in the water, and to prevent it
knocking against the 'ships' side it has a rudder so fixed as to steer, it out from the
side.
•
Dated this Sixth day of October 1894
-T
1. 14
WILLIAM DAVID WHYTE.
DAVID MUIRHEAD.
"
"
Improvements in and relating to Electrio Ship Logs, and Speed
Indicators,
71.
.
WILLIAM DAVID WHYTE Nautical Instrument Maker 144 Broomielaw Street
Glasgow, and David Muirhead Engineer 244 Cumberland Street Glasgow do
hereby declare the nature of this invention, and in what manner the same is to
De performed, to be particularly described and ascertained in and by the following.
statement:-
*200*
This invention is for the purpose of ascertaining the distance, run by ships at sea,
also the speed at any given moment, by means of an electro, mechanical indicator
which may be placed either on the bridge, or in the wheel house, or other suitable
'place. By means of this system the navigator is enabled to see at a glance the
distance the ship.bas travelled, also the speed the vessel is going without leaving
his position on the bridge, thereby saving another person going to the stern of the
vesel to note the log, as is the common practice, and so save time, also, prevent's
those annoying mistakes which are so common when running a course, or a four
111.

page_text: information is generally conveyed to the navigator by a second party.
The usual log consists of a series of wheels geared into each other which are set
in motion by a propeller drawn after the ship, and registers on the 'taffrail at the
extreme aft end of the ship, the friction rollers, and indicator being all in one case,
it will easily be understood that the large number of revolutions the instrument has
to perform, wears out the wheels, and other mechanical parts; so that the usefulness
of the machine is very often spoiled for want of attention in oiling, and the like; it
not being in a convenient part of the ship where it can be easily got at.
In order that our said invention, and the manner of performing, or carrying the
same into effect, or practice may be properly understood, we have hierounto
appended an explanatory set of drawings in which the same reference letters are
used' to indicate corresponding parts in all the letters where shewn:
Figure 1 is an elevation of a propeller.
Figure 2 is an elevation of the mechanism:
Figure 3 is a section of the contact compartment."
Figure 4 is an elevation of the indicator, part of the dial being broken away!
Figure 5 is a view of ratchet wheel, and pawl.
The indicator is constructed, as follows.
An electro-maguet, or electro-
magnets S are attached to a brass seat which constitutes the foundation for
screwing; or fixing the after mentioned parts on.
Attached to the maguet is the usual iron armature T, on the loose end of the
armature is fixed a pawl, or cliteli A, then a steel spindle with a worm B on the
centre, and a ratchet wheel C at the end, this fixed on the brass seat on a
parallel line a short distance from the armature, supported by two upright sockets,,
so that it will revolve freely, and placed in position that the pawl, or clutch A will
grip the teeth of the ratchet wheel C, the pawl A is pressed on the ratchet wheel C
by means of a small steel spring a, or other suitable adjustment, so that when the
armature is moved towards the magnet the pawl A pulls round the ratchet wheel C
one tooth, and causes the spindle, and worm B to revolve slightly (c is a pawl for
maintaining the wheel C in position).
Fixed into the worn B is a piuion wheel' D placed in an upright position, so that
when the spindle revolves the worm B causes the pinion wheel D to revolve
slightly, and indicates (by means of a hand fixed' on the end of the pinion) the
miles or parts of' miles on a dial:
Revolving with this pinion wheel is a brass arm E about one inch long, and at a
anitably placed position is another pinion wheel F with suitable number of teeth,
so constructed that when the brass arm E makes cue complete revolution it comes
into contact with the large pinion wheel Fand moves it round one tooth which
indicates by a smaller hand on the dial fifty, or other convenient number of miles,
that is to say, one revolution of the first pinion wheel D will register fifty miles on
the outer, or large circle on the dial, and at the same time press round the second'
pinion wheel F which will register fifty miles on tlie small, or inner circle on the
dial by the hand V.
The arm on the first pinion wheel D disengages itself from the second' pinion
wheel 'F, and continues to register the milcs, or parts of miles, as already
described.
In cases where a very large mileage is required we do away with the chronograph
movement for registering the fifty miles on the smaller dial, and substitute the
following.
A worm is arranged on the centre spindle, and geared into a pinion wheel, which
wheel is again geared into another wormn; and fixed into the toothed wheel F whichi
indicates on the small dial the total mileage, this enables us to get a much larger
record on the same size of dial.
The whole movement is fitted into a brass case with terminals s fitted for
connecting the wires.
An ordinary electric bell is connected to this indicator either in the inside, or on
1

page_text: the outside of the indicator, and it is arranged, so that the current passes through
the indicator, and bell simultaneously, so when the indicator makes one movement the
bell rings, but should the bell not be required the current can be switched off, and
leave the indicator to work silent.
The second combination of improvements are connected with the propellor, and
the break, and contact mechanism. A propeller, or rotator G is fitted into a
frame II, so as to allow it to revolve freely on a bearing g and a bearing pin y 1,
or rollers at the bottom of the frame, and fits by means of a shaft I through a bush
into a water tight compartment J, and is there connected to a worin K, into which
the teeth of a wheel Lare geared, so that when the propeller, revolves it turns this
worm, and so causes the wheel to revolve, this wheel on a pin is fixed to the bottom
of the chamber.
Rigidly attached to this wheel is a pin M, and when this wheel has made one
revolution the pin comes in contact with one of the teeth of another wheel N, so
constructed that the pin presses upon one of the teeth, or spokes, and causes this
wheel to revolve until the pin disengages itself.
This wheel is fixed on a shaft which passes through a bulk head W which
separates another chamber O where the break, and contact springs are placed.
On the other end of this shaft (in the second chamber) is fixed in a suitable
position a pin P which when one revolution has been made by the shaft presses
against a spring Y, and causes it to touch another spring X thus forming a contact,
and completing an electrical circuit, and so causes the armature on the magnet in
the indicator (which is connected by wires in the usual way) to be attracted to
the. magnet, and this produces the motion already described, which indicates the
part, or parts of a mile.
When the springs are released by the piu P disengaging itself the current is
broken, and the armature in the indicator springs back, and is ready for the next
contact.
A brass plate covers the top of the second chamber, and another plate covers
the top of the first chamber, and is herinetically sealed, then one solid plate is
screwed over the top of the first mentioned plates, and effectually prevents the
water from entering the chambers.
The idea of having the two chambers, and the mechanism placed in them, as
before described is, because if the break, and contact springs were all in one chamber
the water has a tendency to force its way through the bush that the propeller shaft
revolves in, and gets into the first chamber, so that it would gradually find its way
between the two poles of the springs, and cause the circuit of electricity to become
complete, and would therefore cause the indications on the. indicator to become
unreliable, but the bulk head between the two chambers effectually prevents it
from entering the second chamber, and so keeps the contact springs from that
danger.
The want of the second chamber we consider has been the cause of failure in
all electric logs.
The frame H with all the parts complete is towed after the ship either from the
side, or from behind. When it is towed along side it is attached to the cable, or
wires so that it lies at an angle of about 45° in the water, and to prevent it from
knocking against the ships side it has, a rudder, so fixed, as to steer it out from
the side.
The position of the frame in the water is end on, and a fin Q is provided, so that
it cuts a way for itself through the water.
In some cases we prefer for cheapness to have the break, and contact separated
from the propeller simply by doing away with the frane, and having the case with
the working parts fitted on the taffrail, and connecting the shaft to a rope with
the propeller at the other eud, and drawn after the ship in the usual way.
The connection between the indicator, and the case on the taffrail is made by
insulated wires in the ordinary way. The electric force is generated in a number
of Leclanche battery cells.

page_text: •
To get the speed we have calculated a standard to go by namely. If the bell
rings once in 60 seconds the speed is twelve knots per hour, if it ring in 65 seconds
the speed is eleven knots, but if it rings in 55 seconds the speed is thirteen knots,
that is to say every 5 seconds fast, or slow of sixty seconds is one knot faster, or
slower, as the case may be.
Having now particularly described, and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
1. An electric ships log, or logometer in which a propeller towed by the ship
rotates, and by such rotation moves an arm which at intervals closes an electrical
circuit which includes an electro-magnet, the armature of which being attracted to
the magnet operates a pawl, which by means of intermediate mochanism moves.
one, or more hands which indicate upon a dial the number of miles traversed
substantially, as described, and shewn.
2. A propeller for an electric ships log consisting essentially of a spindle having
one, or more blades arranged, a worm, and wheel the latter having an arm which
at intervals moves a star wheel, an arm upon the spindle of the latter which at
intervals closes a contact, and thereby completes an electrical circuit substantially
as described, and shewn.
3. An indicator for an electric ships log consisting essentially of one, or more
electro magnets, an armature for the same which operates a pawl, a ratchet wheel
(moved by such pawl) which has rotating with it a worm which in turn causes a
worm wheel to rotate, an arm upon the latter which at intervals moves a toothed
wheel, and hands upon the spindles of the wheels which indicate upon a dial the
number of miles travelled substantially, as described, and shewn.
4. In an electric log separating the chamber which contains the electric contacts
from the chamber which contains the gearing by a bulkhead substantially in tho
manner, and for the purpose herein before described, and shown in the drawings
annexed.
Dated this Eighth day of July 1895.
WILLIAM D. WHYTE.
DAVID MUIRHEAD: