Improvements in Electric Clocks.
Year: 1893

page_text: Date of Application, 9th Feb., 1893
Complete Specification Left, 9th Nov., 1893-Accepted, 3rd Feb., 1894
PROVISION
Improvements in Electric Clocks.
We, HERBERT SCOTT of 27 Welbury Drive Bradford in the County of Yorks
anufacturer, and HENRY KING BURNET of 79 St. Mary's Terrace Bradford in
e County of Yorks Vitriol Manufacturer do hereby declare the nature of this
vention to be as follows:-
3
It consists of improvements in electric clocks and has reference to those clocks
which the power to drive the train of wheels is obtained by a battery acting on a
endulum, or balance wheel, through an electro-magnet.
'
The object of this invention is to simplify the construction of electric clocks and
ncrease their reliability by the use of a fixed momentary contact made by the
evolution of one of the clock shafts at regular intervals.
The pendulum is provided with a pawl acting on a ratchet wheel which is moved
one tooth by each stroke of the pendulum, this ratchet holds one or more platinum
pins or a platinum pin or other suitable contact point is fixed to the ratchet shaft
or other convenient shaft or wheel in the train and is arranged to make a momentary
connection with a fixed platinum or other contact point at regular intervals
determined by the revolution of the shaft which carries the pin. This connection
occurs at the exact moment when an armature fixed on the pendulum is approaching
an electromagnet thus sending a current through the magnet and giving the pendulum
an impetus. The swing of the pendulum carries the pin past the fixed contact
point & drives the clock till the pin is again brought round when the same is
repeated. The exact moment of contact may be adjusted by means of a regulating
screw, and if convenient two or more pins or contact points may be used where
only one has been mentioned in the foregoing.
A good connection is insured by a mercury contact with the shaft which carries
the pin, or by one or more flexible springs or wires which bear on the platinum pin,
or on the shaft, when the pin is in contact with the fixed contact point.
The clock may be regulated by means of a weight movable by a screw thread on
the pendulum rod.
To counteract the effect of any variation of the battery, the swing of the
pendulum is arranged considerably in excess of what is required to drive the clock,
and a bell crank lever pivoted on the pendulum rod has one end connected with the
driving pawl and the other with a radial rod working on a pivot, this rod being
inclined at such an angle that the motion of the pawl is limited and only one tooth
of the ratchet taken at each stroke whatever the distance travelled by the
5 pendulum. To obtain the same effect the rocking shaft of the pendulum may be
provided with a toothed wheel gearing into a smaller wheel which carries the
driving pawl & limits the motion of it.
In the case of a balance wheel clock the contact is made in the manner described
above. The balance wheel is driven by an electromagnet which is placed so as to
40 exert a pull on the balance wheel when contact is made. The impetus of the
balance wheel drives the clock till the next contact is made by the revolution o
one of the clock shafts, the circuit being momentarily closed at regular intervals a
before described. The methods employed in the pendulum clock to limit th
motion of the driving pawl may be applied in the balance wheel, clock to limit th
motion of the driving pawl which is actuated by the balance wheel.
To apply this invention to a striking clock the hour hand wheel of the clock
used to wind the spring of an ordinary striking train. The hour hand wheel

page_text: geared into a toothed wheel which fits loosely on the spring shaft of the striking
train and carries the spring. One end of the spring is fixed to the shaft and the
other end to the loose wheel; the amount of spring unwound by the striking of
the clock in twelve hours being equivalent to the amount of spring wound by
the going train.
Dated this 8th day of February 1893
COMPLETE SPECIFICATION.
Improvements in Electric Clocks.
We, HERBERT SCOTT, of 27, Welbury Drive, Manningham, in the County of
York, and HENRY KING BURNET, of 79, St. Mary's Terrace, Manningham,
aforesaid, Vitriol Manufacturer, 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 :-
This invention relates to improvements in that type of electric clocks in which
the power required to drive the clock is derived from a battery exciting an electro-
magnet arranged to intermittently attract an armature carried by the pendulum
or balance wheel of the clock. The object of the invention is to simplify the
construction as well as increase the reliability of this type of clock.
In order to fully describe our invention reference is made to the accompanying
sheet of drawings forming a part of this Specification in which similar letters of
reference indicate corresponding parts in each of the figures.
Figure 1, represents a back view of such parts of a clock as are necessary to
illustrate the application of our invention.
Figure 2, represents a side view.
Figure 3, represents a plan view.
Figure 4, represents the contact maker in the position shown in Figure 1 but on
an enlarged scale.
Figure 5, is a plan view of a balance wheel and such other parts as are necessary
to illustrate the application of our improvements to a balance wheel clock.
Figure 6, is a side view of the same looking in the direction of the arrow, with
the pawl and ratchet wheel shown in the former figure omitted.
The electro magnet A is of the horse-shoe type and the wire A' from one of its
coils is directly connected to the binding screw B fixed in the base board C which
latter is shown broken away in Figures 1 and 2 and omitted in Figure 3 to
economise space. The wire D from the other coil of the magnet is connected to
the thin metal spring D¹ fixed by the screw F to the small block F of vulcanite
(or other non-conductor) carried by the metal attachment piece F2 fixed upon
the metal bridge G connecting the two pillars G1, G2 upon which the clock is
shown to be mounted. The spring D' is provided with a platinum tip E, and a
thin platinum wire or platinum tipped wire E¹, made sufficiently long to be springy,
is connected by the screw f to the piece F2 so as to be metallically connected to the
wire D connecting the base of the metal pillar G' with the binding screw B'. A
battery composed of Leclanché or other suitable cells is connected in the usual
way to the two binding screws B and B'.
The pendulum rod H is hung in any suitable manner, and is shown in the
drawings suspended by the spring or thin strip of metal H carried by the cock or
split stud H fixed in the plate H³ attached to the back plate H* of the clock. The
pendulum has a soft iron armature H' secured to the bottom and is provided with
a regulator weight He mounted above upon the portion H' which is cut with a
screw thread.
The pendulum H has a bell crank lever J lightly pivoted to it by means of the

page_text: H, and this lever has an arm J' pivoted to the
shaft or arbor J. The arbor J³ is pivoted in both the back plate H and the
at plate H and may be curved as shown for the purpose of balancing the rod J
well as to clear any of the wheels of the clock-work that may extend across the
s of oscillation. To afford a double bearing for the lever J on the pin H8 the
n J is extended by the piece J' bent round to the back of the pendulum.
e other arm J, Je of the lever J is made double one portion projecting
rectly from the root of J* and the other from the extremity of J³. A wire
wl J is pivoted between the arms Je, and its free end rests upon the ratchet
heel K. The ratchet wheel K is fixed upon the arbor K' provided with a
nion K' arranged in any convenient way to drive the train of wheels of the clock.
he arbor K also carries an arm L (balanced by the piece L' diametrically
pposite) carrying a (platinum) pin L at its extremity.
When the pendulum is put in motion the pin H carrying the lever J obviously
wings with it but the radial rod J' by confining the movement of the extremity
of the arm J to a curve concentric with J³ causes Jo, Je to vibrate in the reverse
lirection to the pendulum. And the centre J³ is so arranged in relation to the
point of suspension of the pendulum and the pin H8 that the extent of the vibration
of Je does not vary to any considerable extent notwithstanding the oscillation of
the pendulum may vary between the minimum oscillation required to operate the
ratchet K in the manner hereinafter described or a maximum oscillation caused
by a battery power over and above that required to maintain such minimum
oscillation.
When the arms Je are vibrated in this manner the pawl J' will operate the
ratchet K one tooth at each vibration and the parts are so arranged that once in
each revolution of the arbor K' the pin L' comes in contact with the springy wire E¹
and whilst rotating in contact therewith momentarily comes in contact with the
wire E thereby completing the electric circuit of the electro-magnet which is
momentarily excited. This momentary excitation of the magnet is arranged to
take place just as the armature at the end of the pendulum is approaching the
poles A2, A2 of the magnet and such amature being instantaneously attracted
thereby a sufficient impetus is given to the pendulum to enable it by continuous
The action of the pin L² in relation
vibration to impart another revolution to the ratchet wheel when it again receives
an impetus in the before mentioned manner.
5 to the wires E and E' is clearly shown in Figure 4 in which a sectional view of
the pin is shown in the position it occupies when first engaging the wire E', and
the broken lines represent said pin when by further rotation it has sprung the
wire E' aside and is on the point of engaging and passing the wire E to complete
A screw F³ fitted in the block F' is arranged to bear against the
the circuit.
40 spring D' to enable the position of the wire E to be adjusted to regulate the poin
at which contact with the pin L' takes place as well as the length of time the
A pendulous arm N having its lower end bent at right angles
are in contact.
engage the teeth of K may be provided to prevent K turning in the revers
direction to that required to drive the clock.
45
othe
any
It is obvious that the pin L2 may be carried by a wheel or attached in
convenient manner to its arbor; and that two or more pins may be used, arrange
to make two or more contacts during each revolution of the arbor.
In Figures 5 and 6 the armature H is shown placed diametrically across t
balance wheel h and the "staff" or arbor h¹ of this wheel lies midway betwe
50 the poles A2, A² of the electro-magnet. The arbor is pivoted below in t
plate ² and passes through the top plate h³. The crank is mounted upon t
end of the arbor projecting above h³ and to this crank the light rod O is pivot
The other end of the rod O is connected to the lever O' loosely mounted
arbor K2 of the ratchet wheel K or upon an adjacent stud. The lever Oca
55 a pawl O engaging the ratchet wheel K and a light spring O³ is provided to k
it in contact with the teeth. The balance wheel is fitted with the usual "ha
spring and is arranged to vibrate about 180 degrees as usual and the leve

page_text: is of such a length in relation to the crank that at each vibration the pawl O'
turns the ratchet K one tooth.
To apply this invention to a striking clock the hour hand wheel of the clock is
used to wind the spring of an ordinary striking train. The hour hand wheel is
geared into a toothed wheel which fits loosely on the spring shaft of the striking
train and carries the spring. One end of the spring is fixed to the shaft and the
other end to the loose wheel. The loose wheel is turned by the going part of the
clock. The amount of spring unwound by the striking of the clock in twelve
hours being equivalent to the amount of spring wound by the going train. But
we make no claim to this striking arrangement.
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. In a clock operated by an electro-magnet, the arrangement in which the
circuit of the electro-magnet is closed or completed at regular intervals by one of
the clock arbors carrying a contact pin or piece which on rotation is adapted to
engage a contact wire or point, substantially as herein shown and described.
2. In an electric clock, the combination with the pendulum, of a lever pivoted
thereon and provided with a pawl adapted to operate a ratchet wheel, and a radial
rod or its equivalent arranged to limit or confine the motion of said lever,
substantially as herein shown and described and for the purpose specified.
3. In an electric clock, the combination with a rotating contact piece, of a
flexible or springy contact wire, (in connection with one pole of the battery)
which the contact piece is first arranged to engage, and a second contact wire
(connected to the other pole of the battery) which the contact piece is arranged to
momentarily engage as well, substantially as herein shown and described.
4. The combination with the contact point E of the adjustment screw F³,
substantially as herein shown and described and for the purpose specified.
Dated this 7th day of November 1893.
DRACUP & NOWELL,
Bradford, Agents.