An Improved Electric Clock.
Year: 1893

page_text: Date of Application, 25th Jan., 1893
Complete Specification Left, 24th Oct., 1893-Accepted, 20th Jan., 1894
An Improved Electric Clock.
We, GUSTAV BINSWANGER, of 71 Queen Victoria Street, in the City and
County of London, Electrician, and HERBERT JOHN COATES, of 11 Nelson
Street, Braughton, Manchester, in the County of Lancaster, Electrical Engineer,
do hereby declare the nature of this invention to be as follows:-
Our invention relates to an improved electric clock, having for its objects the
attainment of a regular and uniform impulse to the pendulum of practically
unvarying force, although the strength of the electric current, driving it may vary
considerably, thus ensuring correct timekeeping independently of said current.
In carrying our invention into practice, we attach to the frame, carrying the
necessary train of wheels, a bracket, holding the pendulum, and its driving
mechanism hereinafter to be described. Said bracket and the pendulum is
insulated from the rest, of the mechanism, of the clock. A weighed lever, or
gravity arm is pivotted behind the pendulum, and the arbor or spindle thereof, is
as nearly as possible arranged, to coincide with the point of suspension of the
former. Said gravity arm may either be bent outwards, or be fitted with an
extension carrying an adjustable weight, so that the centre of gravity may be
arranged by formation, or adjustment to afford the impulse with the least possible
friction. At a certain distance from the point of suspension of the pendulum
attached a platinum, or other contact piece, a corresponding contact piece being
fitted to the gravity arm, so that electrical contact is established between them
during a part of the period of oscillation. An electro-magnet is attached to the
frame, and carries a pivotted armature (preferably placed vertically) to which is
fixed a lifting arm, so arranged that by means of a pin, can raise the gravity arm
by striking it at its lower extremity. The upper part of the pivotted armature
carries a pawl, which engages with the teeth of a ratchet wheel, upon the spindle
of which is a pinion which gears with the clock train. One end of the coils of the
electro-magnet is connected to the insulated support of the pendulum, and the other
end to one terminal, coupled with the source of current, the other end being
connected through the gravity arm to the opposite terminal thereof, or any
equivalent means for coupling may be provided.
The action may briefly be described as follows:―
When the current is applied, and the pendulum started, the contact piece thereon
touches that of the gravity arm thus lifting it off the pin of the armature, and
carries it with it as it swings in one direction, also closing the circuit of the electro-
magnet while they swing in unison. The electro-magnet is vitalised directly the
pendulum lifts the gravity arm, the armature is attracted, and the extension thereof
is depressed, and remains so while the pendulum and gravity arm strikes the pin on
the extension, the motion is arrested while the pendulum continues to swing, and
the electrical contact is broken, therefore the armature assumes its normal position,
either by the action of gravity, or by a suitable spring, and the extension or lifting
lever attached to it, raises the gravity arm to its highest position thereby storing
sufficient energy to give an impulse to the pendulum, when it is released, said
impulse being due to the fall of said gravity arm from such position to that deter-
mined by the position of the pin on the extension or lifting lever, when the armature
is attracted by the electro-magnet.
The pawl connected to the other end if the armature engages, either during the
forward stroke of said armature, or when desirable, during the back stroke thereof,

page_text: with a tooth in the ratchet wheel, so that for each complete oscillation of said
armature, the wheel is turned by the amount of one tooth. Thus, by providing
this wheel with a suitable number of teeth, the number of beats made by the
pendulum can, by means of the pinion before described and the gearing in con-
nection therewith be recorded in the usual way. By allowing the armature to open
and close the electric circuits of secondary clocks, one standard clock may be
caused to operate any number thereof synchronously, from a single central source
of electricity.
Instead of the clectromagnet becoming energised by the contact of the gravity
arm and pendulum, it may be connected (through proper resistances) in such a
manner that it is normally energised or magnetic, the armature being held to the
poles, the lifting pin consequently resting at its lower position. The gravity and
said lifting pin being suitably insulated from each other the terminal wires of the
electro-magnet are also connected, one to the gravity arm, and the other to the
lifting pin aforesaid, so that when, during the swing of the pendulum, the gravity
arm, and lifting pin are in contact, the coils are short circuited, and therefore
demagnetised. The armature thus falling from the poles, raises the extension or
lifting arm, and pin lifting the gravity arm to its highest position. The backward
swing of the pendulum raises said gravity arm from the pin, carrying it with it in
its' motions, and the contact between said gravity arm and lifting pin is thereby
broken, and the coil is no longer short circuited and it again becomes energised
bringing the lifting pin to its lower position.
Dated this 20th day of January 1893.
FREDK. WALKER,
11, Furnival Street, Holborn, London, E.C., Agent for the Applicants.
An Improved Electric Clock.
We GUSTAV BINSWANGER, of 71 Queen Victoria Street in the City and County
of London, Electrical Engineer and HERBERT JOHN COATES, of 11, Nelson Street
Manchester in the County of Lancaster do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
Our invention relates to an improved electric clock having for its objects the
attainment of a regular and uniform impulse to the pendulum, of practically
unvarying force, although the strength of the electric current driving it may vary
considerably, thus ensuring correct time keeping independently of said current
strength, and its variations.
In order that our invention may be clearly understood, we have appended the
accompanying sheet of drawings in which Figures 1. 2 and 3 represent the different
modifications embodied in our Specification describing our said invention.
Similar letters of reference indicate corresponding parts in the several views.
In carrying our invention into practice, we attach to the base plate, or frame
carrying the train of wheels, a bracket or split block A, which is insulated from
s:id frame. A gravity arm C is shewn pivotted in Figure 1, and suspended by a
flexible spring in Figures 2 and 3, the centre of motion of the said arm being
arranged to coincide approximately with that of the pendulum B. Said gravity
arm may be bent outwards as shewn by the drawings, or may be provided with an
extension arm carrying a weight or counterbalance, so that the centre of gravity
may be correctly arranged by formation, or by adjustment when required, so that
the desired force may be obtained for the impulse at each stroke of the pendulum.
Referring to Figure 1 a platinum or other suitable contact piece is fixed upon the

page_text: pendulum B at a point a, a corresponding contact piece being fitted to the gravity
arm C at b, so that electrical contact is established between them during a part of
the period of oscillation. An electro magnet D is attached to the frame, and carries
a pivotted armature E to which is affixed a lifting arm F in such a manner that by.
striking the gravity arm C the latter may be raised. The end of the armature É
carries a pawl G which engages with the teeth of a ratchet wheel H, upon the
spindle of which is fixed a pinion, gearing with, and communicating motion to a
clock train, which is not shewn in the drawings. One end of the coils of the
electro-magnet D in Figure 1 is connected to the insulated bracket A, and the
other end to the source of the electric current L, and the gravity arm C is also
connected to L, or any equivalent method of coupling the parts together may be
adopted.
In the modification shewn by Figure 2 the lifting arm F carries a contact pin
instead of the pendulum B, the circuit being established when the position of said
pendulum B allows the arms C and F to touch and make contact.
In the device shewn by Figure 1, the action is as follows ;-
When the electric current is caused to traverse the circuit, and the pendulum B
is started, the contact piece a touches upon the gravity arm C, thus lifting it
away from the pin terminating the arm F, carrying it forward as it swings in one
direction, and closing the circuit of the electro magnet D during this period. Said
electro magnet D is vitalised directly the pendulum B lifts the gravity arm C;
the armature is attracted and the extension or lifting arm F is depressed and remains
so while the pendulum and the gravity arm swing together. When, however, these
swing in the opposite direction, and the gravity arm C strikes the pin of the lifting
arm F, the motion of arm C is arrested, whilst the pendulum B continues to swing,
and the electrical contact is consequently broken, therefore the armature E assumes
its normal position, and the arm Fattached to it then raises the gravity arm C to
a higher position, thereby storing sufficient energy to afford an impulse to the
pendulum when it is released, said impulse being due to the fall of the gravity
arm C from such position, to that determined by the position of the pin in the
lifting arm F when the armature is attracted by the electro-magnet D. The
pawl G engages either during the backward or forward stroke of the armature
with a tooth in the ratchet wheel H so that for each complete oscillation of
the said armature, said wheel I is rotated within the space of one tooth,
circumferentially. Thus, by properly grading the wheel I, and its connection
with the train of gearing, each beat of the pendulum B may be recorded in
the usual manner, by index points, hands, moveable figures or the like.
In the modification shewn by Figure 2, the gravity arm C falls upon the lifting
arm F, thus completing the electric circuit, when the armature E is attracted, thus
lifting the gravity arm C by the arm F to a higher position; and the pendulum B
in swinging carries the gravity arm C with it, breaking the electric circuit between
the arms C and F at the same time, and said armature E in falling takes with it
the lifting arm F restoring the latter to its lower position. In some cases of
application the lifting arm F may be separately pivotted, and so weighted that the
lifting force may be regular, the armature E raising the lifting arm, which in falling
is caused to move the gravity arm C and operate the contacts as before described.
In the modification shewn by Figure 3, instead of the electro magnet D being
energised or vitalized by the contact of the gravity arm C with the pendulum Bas
shewn by Figure 1, or by the contact between the gravity arm C and the lifting
arm F as in Figure 2, it is connected through a suitable resistance R, directly to
the source of current L, so that normally it is vitalized, and the armature E held
to its poles, the pin on the lifting arm F being at its lower position in consequence
thereof.
The coils of the electro magnet D being in connection with the source of
current L, are also connected as a shunt one to the gravity arm C, and the other to
the lifting arm F. When, during the swing of the pendulum these two arms make
contact through their separate contact pieces by reason of said shunt connection

page_text: and the coils of D are short circuited, and therefore demagnetized. The armature E
then falling from the poles raises the lifting arm F allowing the gravity arm C, to
swing to its lowest position. The backward swing of the pendulum B raises the
gravity arm C, from the lifting arm F by pressing against it, an'l the electrical contact
between the arms C and F is thereby broken, and the magnet coils being no longer
short circuited the electro-magnet D is again vitalized bringing the arm F to its
lower position.
A conspicuous advantage is in that the arrangement of the contacts obviate
sparking and the consequent oxidation and deterioration thereof.
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 ;-
First. In an electric clock, the combination of a gravity arm C, making electric
contact with a pendulum B, and lifted by an arm Fon or connected to an
armature E of an electro magnet D, with a clock train, feeding and recording
apparatus substantially as herein described with reference to the drawings.
Second. In an electric clock as referred to in the preceding claim, the
modification comprised in causing the gravity arm C making electrical contact
with the lifting arm F, substantially as and for the purposes herein set forth with
especial reference to Figure 2 of the appended drawings.
Third. In an electric clock as referred to in the preceding claims the
modification comprising the arrangement whereby the gravity arm C and lifting
arm Fare placed so as to short circuit the coils of a magnet D, substantially as
herein described with especial reference to Figure 3 of the appended drawings.
Dated this 20th day of October 1893.
FREDK. WALKER,
73, St. Stephen's Road, Upton Park, E.C., Agent for the Applicants.