IMPROVEMENTS IN ELECTRIC CONTROLLER AND INDICATOR PROVISIONAL SPECIFICATION FOR CLOCKS AND FOR OTHER PURPOSES
Year: 1882

page_text: LETTERS PATENT to Thomas Wright The Eastern Telegraph Company Malta,
for an Invention of "IMPROVEMENTS IN ELECTRIC CONTROLLER AND INDICATOR
PROVISIONAL SPECIFICATION left by the said Thomas Wright at the
Office of the Commissioners of Patents on the 29th August 1882.
THOMAS WRIGHT-The Eastern Telegraph Company Malta
"IMPROVEMENTS
"
IN ELECTRIC CONTROLLER AND INDICATOR, FOR CLOCKS AND FOR OTHER PURPOSES
I make a controller which consists of a cogwheel with two ratchet wheels fixed
on each side, working on an axis. The axis also bears two levers at one end of
each is a spiral spring, or weight, at the opposite ends are placed a click and an
armature, communicating with a small toothed wheel the axle of which also carries
a circuit closer, viz:-a wheel made of a non conducting material, with a metal
ring round it from which project branches or pawls at certain distances. On this
wheel press four steel springs, one which is connected to a terminal of the battery
rests on the metal ring, two are connected to the ends of the coils of the electro-
magnets under the levers, and the other one to the coil of the electro magnet in the
indicator, the corresponding ends of the coils being connected to the other terminal
of the battery, or to earth. When one of the projections from the ring on the
circuit closer makes contact with one of the springs connected to the coil of an
electro magnet under the armature of one of the levers the latter is drawn towards
the magnet by the current traversing the coil, but the instant the circuit is broken
by the circuit closer continuing its course the lever is set free, the click is caught
in the ratchet wheel, and the cog wheel being attached it is forced round by the
action of the spring at the other extremity of the lever, thus communicating motion
to the circuit closer.
The object of having two levers is that before the force of one spring is spent to
make the circuit closer close and open the circuit in which is the electro magnet
under the opposite lever, the latter is then brought into operation and performs the
same functions as the other in the manner described, each lever acting alternately

page_text: thereby causing the circuit closer to be constantly in motion.
regulated by an ordinary clock escapement,
The rotation being
The indicator having a ratchet wheel with 120 teeth also another wheel with
slots corresponding to every twelfth tooth of the ratchet wheel, these two wheels
are made fast, a little apart, to one end of a small rod, to the other end of the rod
which passes through the dial, is fastened a finger for indicating the minutes-I
also employ another ratchet wheel of the same size and number of teeth as the
other, fixed to one end of a small brass tube, the finger for indicating the hours
being at the opposite end, this tube works on the rod carrying the minute finger.
A lever in an upright position and working on a fulcrum is placed opposite the
wheels. At the lower extremity of the lever is an armature which is in close
proximity to the electro magnet under the wheels, at the other extremity of the
lever are two clicks which rest on wheels. One end of the coil of the electro
magnet being connected to the spring in the controller. As the circuit closer
revolves the projections from the ring come in contact every thirty seconds with
this spring thereby closing the circuit which has the effect of drawing that end of
the lever to which is fixed the armature towards the magnet, as soon as the contact
is broken the lever is made to resume its former position by the action of the spring
and in doing so the click falling into the teeth of the ratchet wheel moves it forward
the extent of one tooth the distance being limited by stop pins, the finger making
a corresponding movement on the dial equal to half a minute as there are 120 teeth
in the wheel which is moved the space of one tooth every thirty seconds it will
consequently make a complete revolution in one hour. The wheel being slightly
larger than the ratchet-wheel the click resting on the former does not affect the
latter, to which is attached the hour hand, except when one of the slots comes
under the click, it is then moved forward one tooth, the finger making a corre-
sponding movement on the dial. There being only ten slots in the wheel or one
to every twelve in the ratchet wheel it follows that the finger attached to the latter
is moved forward equal to half a minute on the dial, or five minutes every hour, to
six minutes, or one hour of the minute hand.
The metallic contacts on the circuit closer are arranged so that contact cannot be
made by any spring except the one intended, and also that only one circuit can
be closed at a time, thus giving the full power of the battery to each circuit.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Wright in the Great Seal Patent Office on the
23rd February 1883.
THOMAS WRIGHT of the Eastern Telegraph Company Malta.
"IMPROVEMENTS
IN ELECTRIC CONTROLLER AND INDICATOR FOR CLOCKS AND FOR OTHER PURPOSES
"
I make a controller which consists of a cog wheel with 2 ratchet wheels fixed on
each side, working on an axis. The axis also bears two levers A. A¹. at one end of
each is a spiral spring, or weight, at the opposite ends are placed a click and an
armature. Communicating either direct, or by a train with wheel B is a small
toothed wheel the axle of which also carries a circuit closer, viz: a wheel made of
a non-conducting material, with a metal ring C round it from which project
branches or pawls at certain distances. On this wheel press four steel springs, one
which is connected to a terminal of the battery rests on the metal ring, two are
connected to the ends of the coils of the electro magnets under the levers, and the
other one to the coil of the electro magnet in the indicator, the corresponding
ends of the coils being connected to the other terminal of the battery, or to
earth. When one of the projections from the ring on the circuit closer makes
contact with one of the springs connected to the coil of an electro magnet
under the armature of one of the levers the latter is drawn towards the magnet by
the current traversing the coil, but the instant the circuit is broken by the circuit
closer continuing its course the lever is set free, the click is caught in the ratchet
wheel, and the cog wheel being attached it is forced round by the action of the
spring at the other extremity of the lever, thus communicating motion to the
circuit closer.
The object of having two levers is that before the force of one spring is spent to
make the circuit closer close and open the circuit in which is the electro magnet
under the opposite lever, the latter is then brought into operation and performs the
same functions as the other in the manner described, each lever acting alternately
thereby causing the circuit closer to be constantly in motion. The rotation being
regulated by an ordinary clock escapement or other suitable means.
Figure 2 is the indicator A being a ratchet wheel, with 120 teeth B is also
another wheel with slots corresponding to every twelfth tooth of the ratchet wheel,
these two wheels are made fast, a little apart, to one end of a small rod, to the
other end of the rod which passes through the dial, is fastened a finger for
indicating the minutes. I employ another ratchet wheel A¹ of the same size and
number of teeth as the other, fixed to one end of a small brass tube, the finger for
indicating the hours being at the opposite end, this tube works on the rod
carrying the minute finger-a lever in an upright position and working on a
fulcrum is placed opposite the wheels. At the lower extremity of the lever is an
armature which is in close proximity to the electro magnet under the wheels, at
the other extremity of the lever are two clicks which rest on wheels A and B. One
end of the coil of the electro magnet being connected to the spring in the controller.
As the circuit closer revolves the projections from the ring come in contact every
thirty seconds with this spring thereby closing the circuit which has the effect of
drawing that end of the lever to which is fixed the armature towards the magnet,
as soon as the contact is broken the lever is made to resume its former position by
the action of the spring C, and in doing so the click falling into the teeth of the
ratchet wheel A moves it forward the extent of one tooth (the wheel B attached to
it of course moving as well) the distance being limited by stop pins, the finger
making a corresponding movement on the dial equal to half a minute as there are
120 teeth in the wheel which is moved the space of one tooth every thirty seconds

page_text: it will consequently make a complete revolution in one hour. The wheel B being
slightly larger than the ratchet wheel, the click resting on the former does not
affect the latter, to which is attached the hour hand, except when one of the slots
comes under the click, it is then moved forward one tooth, the finger making a
corresponding movement on the dial. There being only ten slots in the wheel B or
one to every twelve in the ratchet wheel A' it follows that the finger attached to
the latter is moved forward equal to half a minute on the dial, or five minutes every
hour, to six minutes, or one hour of the minute hand.
The metallic contacts on the circuit closer are arranged so that contact cannot be
made by any spring except the one intended, and also that only one circuit can be
closed at a time, thus giving the full power of the battery to each circuit.
The wheels in the indicator could of course be made to move by the direct action
of the electro magnet instead of by the spring, but the latter as explained is the
most suitable plan.
Having now described and ascertained the nature of my Invention and the
manner in which the same is or may be performed I would observe in conclusion
that I do not limit myself to the precise details herein given and shewn in the
accompanying Drawings as various modifications may be made therein while
retaining the essential features of my Invention, But what I claim as new and
desire to be secured to me by the hereinbefore in part recited Letters Patent is :-
1st The mode of obtaining rotary movement by means of circuit closer and
duplicate levers working in combination with electro magnets and battery in the
manner specified or any modification.
2nd The method described of causing the fingers in the indicator to move in such
manner as to indicate the hours and minutes, without the use of cog wheels, by
means of the ratchet wheels marked A. A. and the wheel with slots marked B and
the duplicate clicks attached to the lever-(the latter being actuated by the battery
in combination with the circuit closer in the controller and the manner of arranging
the same as set forth or any modification thereof.
In witness whereof I the said Thomas Wright have hereunto set my hand
and seal this Thirteenth day of February in the year of our Lord One
thousand eight hundred and eighty three.