An Improved Mode of Driving Clock Mechanisms.
Year: 1893

page_text: Date of Application, 9th Jan., 1893
Complete Specification Left, 9th Oct., 1893-Accepted, 6th Jan., 1894
PROVISIONAL SPECIFICATION.
An Improved Mode of Driving Clock Mechanisms.
I, ROBERT HARKNESS TWIGG of 14, Victoria Street in the City of Westminster,
Civil Engineer, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to drive clock mechanisms through the intervention
of periodic currents of electricity, and thus dispense with the weights or usual
springs which have hitherto constituted the motive power.
In carrying out my invention, I retain the escapement movement, with the
pendulum or hair spring to regulate the movement, as heretofore.
The means which I employ for producing the periodic currents of electricity, are
preferably those described in the Specification of my Patent dated 11th Sept. 1891,
No. 15440.
The invention consists in the combination with the escapement wheel, of a train
of gear wheels and pinions, to which motion is transmitted by means of a spring
finger, which is periodically operated by electricity.
The escapement wheel, say, of 60 teeth, has a pinion of 6 teeth on its arbor,
which gears into a toothed wheel of 60 teeth. This wheel has a pinion of 60 teeth,
gearing with a second toothed wheel of 60 ratchet teeth. This last wheel will
be rotated by the spring, which is drawn up or down by a magnet periodically, as
the current passes (say, once a minute), to take a fresh tooth, and so soon as the
current is shut off, the spring will resume its normal position (viz., one of slight
tension), and turn the wheel the distance of one tooth.
This movement will be communicated, through the multiplying gear above
described, to the escapement wheel, which in turn will act on the pendulum or hair
spring, and keep it swinging. It will be evident that the driving springs may be
duplicated if necessary.
By this means, the clock mechanism is practically driven by electricity, and
when once regulated, will keep perfect time, & work continuously for months
without any winding up, provided the current of electricity is maintained at sufficient
strength.
To start the clock, it will be only necessary to turn the current maker, to make
contact, and start the pendulum.
A clock actuated in this manner will be especially useful for electric meters, as
the current it has to measure is the means of driving the clock mechanisms of the
same.
It may be here remarked, that the means employed in carrying out my invention
may be varied, without departing from the essential feature of the same, which is
to drive the clock mechanism, not by the intervention of weights or springs in the
ordinary way, but by the periodic action of a current of electricity, suitably com-
municated to the clock mechanism, independently of the pendulum or other
regulating device.
Dated this 9th day of January 1893.
NEWTON & SUN,
Agents for the Applicant.

page_text: An improved mode of Driving Clock Mechanisms.
I ROBERT HARKNESS TWIGG of 14 Victoria Street in the City of Westminster,
Civil Engineer, 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 object of this invention is to drive clock mechanisms through the inter-
vention of periodical currents of electricity, which are utilized to raise weights
or wind up springs acting direct on the " centre wheel axle of the clock
mechanism.
"
In carrying out my invention, I retain the escapement with a pendulum or hair
spring to regulate the movement as heretofore, and I also employ the ordinary
train of gear wheels and pinions from the "centre" wheel to the escape wheel, and
the invention consists in the mode of applying the power to this train of wheels to
ensure the swing of the pendulum or the hair spring.
To this end I employ either a light spring or a weight, or both, to push up or
draw down (as the case may be) a pawl or a hooked catch, so as to rotate the
"centre" wheel axle either by acting directly on the teeth of the "centre" wheel,
or through a ratchet wheel fixed on the axle, or in any other convenient manner.
The shifting of the pawl to a fresh tooth is caused (every minute, more or less) by
a periodic current of electricity energising a pair of electro magnets, or a solenoid,
which attract the armature (practically the weight), and winds up the spring, or
raises the weight, or effects both operations. The electric circuit is completed by
means of a suitable contact maker controlled by the clock mechanism.
And in order that my invention may be clearly understood, will proceed to
fully describe the same, reference being had to the accompanying drawing, in
which―
:
Fig. 1 is a back view of the clock mechanism, and
Fig. 2 is a side view.
Figs. 3 and 4 are details of a mercury contact maker; and
Fig. 5 is a diagram showing the clock mechanism, battery, and two dials, in
circuit.
A A' are a pair of clock plates holding the clock mechanism, the said plates being
kept at the proper distance apart by spacing pillars B in the usual way.
"
C is the " centre wheel, which, through a train of pinions and wheels, 1, 2, 3,
actuates the escape wheel D, which is provided with the usual escapement
connected with the crutch of the pendulum.
So far I have described an ordinary clock mechanism.
E is an axle or arbor which projects through the plate A, and through a spring
box F containing a light coiled spring, which is attached in the ordinary way to the
box and the arbor, a fixed pawl holding the box stationary. On the same arbor is
fixed a lever G, having at one end a pawl or catch, which I will term the driving
pawl or catch a, and the other end an armature b, which extends across the
poles of two electro magnets H, and may serve as a weight for driving the train of
wheels..
"
The pawl a may take direct into the teeth of the "centre wheel, but I prefer
that the pawl shall act on a ratchet wheel I, mounted on the same axle or arbor, as
being more suitable for the purpose, and because it can be more conveniently placed
in relation to the other parts of the mechanism.
The weight of the armature b, and the action of the coiled spring F, causes the
driving pawl a to press up (or the the catch to draw down, as the case may be) the

page_text: tooth of the ratchet wheel against which, for the time being, it is resting,
and thus drives the "centre," wheel which in turn drives the escape wheel, as
before explained.
The shifting of the pawl, as I have stated, is caused by a periodic current of
electricity, and I will now explain the means I employ for effecting this
operation.
For the purpose, I may use a mercury contact maker, of the nature shown and
described in the Specification of my Patent dated 11th September 1891, No. 15440;
or I may use a mercury contact maker of the construction shown at Figs. 3 and 4.
The mercury is contained in a length of glass tube c (preferably in vacuo), with
electrical contact (say platinum) points d projecting through one end into the tube.
This tube c I prefer to mount, by one end, in a ring e provided with pivots f, each
in electrical connection with one of the points d. The pivots will work in
metallic bearings in the electric circuit, but insulated from one another, light
springs being used to keep the pivots in proper contact. The normal position of
the mercury will be away from the points d, the tube resting at a slight inclination.
The contact will be made by the periodic tipping of the device, by means of
a tripping pawl acting on a tappet g carried by the device, the device returning to
its normal position by gravity. The ring may, however, be placed at the
centre of the tube, a counterweight being provided to return it to its normal
position.
I prefer, however, to use the contact maker shown in Figs. 1 and 2, which
consists of a metal cylinder mounted in metallic bearings (not necessarily
insulated from one another) in the electric circuit, and provided longitudinally, on
the periphery, with a platinum contact strip and a piece of insulating material.
The cylinder is provided with a tappet g, whereby it may be moved axially by a
tripping pawl, as will be presently explained, and with a counterweight i, to return
it to its normal position.
A light spring (in the electrical circuit) carrying, at its outer end, a platinium
contact point, bears continuously on the cylinder, the point normally resting on the
insulating material, so that when the cylinder h is moved axially by the pawl,
the point on the spring; is brought into rubbing contact with the platinium strip
on the cylinder, thus producing electric contact. k is the tripping pawl, which
swings loosely from one end of a lever l, mounted on a suitable arbor, and having
at the other end a catch-pallet or tooth m, which takes into a tooth of the ratchet
wheel I. This lever 1, with its tooth m, is intended to act as a retaining pawl, and
will be hereafter referred to as such, to prevent the backward motion of the
ratchet wheel I while the driving pawl a is taking another tooth, but it has an
additional duty, viz., that of actuating the contact maker.
It will be seen that the fulcrum of the retaining pawl is close to the catch end,
the long arm beyond the pivot being three or four times the length of the short
arm with the catch, so that the movement of the catch or tooth m dropping into a
tooth of the ratchet wheel, will be multiplied three or four times at the other end.
I thus obtain the requisite amount of motion to effectually tip the contact maker by
the descent of the tripping pawl k, and it will only be when the ratchet wheel I is
effectually locked by the retaining pawl 1, that the electric contact is completed
and the driving pawl a can be moved. A tail on the tripping pawl k, as the pawl
descends, comes in contact with an inclined plane n, and is thus thrown off the
tappet g.
The cylinder is thus free to return to its normal position (out of
contact), under the influence of the counterweight i.
This arrangement of tripping pawl may be adopted with the contact maker
shewn at Figs. 3 and 4, the tube c returning to its normal position by gravity, as
before explained, as soon as the tripping pawl is thrown off the tappet.
The pawl k is gradually raised to the proper position to act on the tappet g by.
the tooth m of the retaining pawl riding up the ratchet tooth.
I find the above described arrangement of contact maker to act satisfactorily,
but I would here remark that I do not intend to confine myself to this particular

page_text: device for ensuring the passage of periodic currents of electricity, as many others
may be devised for the same purpose.
The clock mechanism thus constructed and operated may be used for any
purpose for which it is applicable, as, for instance, the working of any number
of electric dials of suitable character, the electric current passing to the dials
when the contact maker is operated. Such an application is shown in the diagram
Fig. 5.
may, however, find it convenient, where a number of dials are in circuit, to
provide each dial with a relay and a local battery, instead of sending a sufficient
current through the clock and the whole series. Such an arrangement will be
readily understood by an electrician.
I may also find it desirable to provide means for automatically increasing the
battery power in case of need, and for indicating this fact. This may be effected
by the descent of the armature beyond its normal distance (due to the failure of
the battery power to raise it at the proper moment) and into contact with points in
a local circuit, by which the local circuit will be closed, and a switch operated to
throw other cells into the main circuit, the same being indicated by a visible or
other signal. In case of the temporary failure of the main circuit, the local
circuit may be utilized by means of electro magnets, and a system of levers to
raise the main armature to its proper position, and thus ensure the continuous
working of the clock mechanism.
I may also provide the armature, or some other independent moving part of the
apparatus, with a striker, which, on the movement of the armature or other part,
will strike against the tripping pawl k, in case it should fail to trip at the
right moment, and thus ensure the return of the contact maker to its normal
position.
I would here remark that these last named devices form no part of the
present invention; they are intended merely to indicate possible difficulties that
may arise from unforeseen causes during working, and means for overcoming
them.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. The mode of driving clock mechanisms substantially as herein shown and
described, and consisting in conveying the power derived from a light spring or
light weight direct to the axle of the centre wheel, by means of a lever and pawl,
or equivalent device, the shifting or operating of such device, to bring it into a
position to do the work, being caused by an electro magnet energised by a periodic
current of electricity transmitted through a contact maker actuated by a tripping
device controlled by the clock mechanisin, as set forth.
2. The mode of driving clock mechanisms substantially as herein shown and
described, and consisting in rotating the axle of the centre wheel by means of a
pawl, lever, or equivalent device, operated by a light spring or weight, the
rewinding of the spring and the raising of the weight being effected by an electro
magnet energised by a periodic current of electricity, as set forth.
3. In the driving of clock mechanisms as described in Claims 1 and 2, operating
a contact maker to produce periodic currents of electricity by a suitable device
controlled by the dropping of a retaining pawl into the teeth of a ratchet wheel,
as set forth.
4. In the driving of clock mechanisms as described in Claims 1 and 2, the use
of a mercury contact maker of the character described and shown with reference
to Figs. 3 and 4.
5. In the driving of clock mechanisms, producing periodic currents of electricity
by means of a mercury contact maker constructed, arranged, and operated.
substantially as herein described and shown with reference to Figs. 3 and 4 of the
drawings.

page_text: 6. The means for driving clock mechanisms substantially as herein shown and
described.
7. A clock mechanism constructed, arranged, and operated substantially as
herein shown and described.
Dated this 9th day of October 1893
NEWTON & SON,
Agents for the Applicant.