Improvements in Electric Clocks.
Year: 1899

page_text: Date of Application, 12th Dec., 1899-Accepted, 17th Mar.,
1900
CUMI LEIE DIECITICATION.
Improvements in Electric Clocks.
I, JOSEPH BUTCHER, of No. 177, Broadway, in the Borough of Manhattan, and
City, County, and State of New York, United States of America, Mechanician,
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 that class of electric clocks wherein the hands are
driven by a weighted arm or lever which is raised at intervals by the closing of
an electric circuit through an electromagnet; and the object of the present
invention is, in the main, to adapt this means of driving to a movement wherein
the escapement is controlled by a balance-wheel and hair-spring as distinguished
from a pendulum.
In the accompanying drawings, which illustrate an
invention-
embodiment of the
Figure 1 is a rear elevation of the clock mechanism as seen from the right
in Fig. 2, the near plate of the frame being omitted the better to illustrate the
moving parts.
Fig. 1 is a view similar to Fig. 1, but showing the moving parts in a different
position.
:
Fig. 2 is a side elevation, as seen from the left in Fig. 1. The weighted lever
is partly broken away in this view.
Fig. 3 is a fragmentary view designed to illustrate the contacts.
Fig. 4 is a somewhat diagrammatic view illustrating the circuit connections.
1 represents the frame of the clock-movement, in which is rotatively mounted
the usual clock-train. 2 is the main driving arbor, on which is fixed a ratchet
wheel, 3. On the arbor 2 is loosely mounted a sleeve, 4, which carries a weighted
arm, 5, and a spring pawl, 6, which plays over the teeth on the ratchet when
the weighted arm is thrown up, and engages said teeth and drives the arbor 2
when the weighted arm descends.
7 is the arbor which carries the hands of the clock: 8 is the arbor on which
is fixed the escapement-wheel, 9; 10 is the arbor carrying the balance-wheel, 11,
and to which is connected the hair-spring, 12; and 13 is the arbor of the escape-
ment, 14, the pallets of which engage the teeth on the escapement wheel. This
arbor 13 also carries the lever, 15, the forked end of which engages a pin, 16,
in the boss of the balance-wheel, as clearly shown in Fig. 1", from which the
hair-spring has been omitted so as to better show this feature.
Mounted in an inclined position in the frame 1, is an electromagnet, M, the
armature, a, of which is mounted on an arm, 17, fixed to an arbor, 18, mounted
in rocking bearings in the upper part of the frame.
Normally the armature hangs in the nearly vertical position seen in Fig. 1;
but when the magnet is excited its attraction draws said armature into substan-
tially the position seen in Fig. 1º, rocking the arbor 18 in its movement. When

page_text: in its normal position (Fig. 1) the armature rests against a cushion, 19, in the
frame.
G represents a battery or any other suitable electric generator, and w, w³,
the conductors of an electric circuit including said generator and the electro-
magnet M. Fig. 4 best illustrates the circuit terminals; is the terminal of
the conductor w, and the terminal of the conductor w. The terminal tis
in the nature of a pin, set in an insulating block in a metal arm, 20, carried by
the arbor 18; and the terminal is in the nature of a leaf spring, secured to the
underside of the arm 20, with its free end slightly out of contact, normally,
with the terminal t. For convenience, a block, 21, of insulating material is
mounted on the rocking arbor 18, and the circuit-wires are brought to this point,
where the connections are made in a well known way.
On the arbor 18 at the side of the arm 20, is an operating arm, 22; and in
the arm 6, which carries the pawl 6, is a laterally projecting pin, 23, the
function of which will appear from the description of the operation following.
Starting from the position of the parts seen in Fig. 1ª, which shows the
weighted arm 5 elevated to a nearly vertical position, the weight descends
gradually, driving the clock train as fast as the escapement will permit. When
it shall have descended to the position seen in Fig. 3, the pin 23, in the pawl-
arm 6, takes under the terminal spring, and presses it upward into contact
with the terminal t, thus completing the circuit through the magnet M. At the
same moment the pin 23 is brought up under the operating arm 22 (partly
broken away in Fig. 3); and the instant the circuit is closed the magnet draws
the armature a to the position seen in Fig. 1ª, with a sudden movement, which
serves to cause the arm 22 to impinge upon the pin 23 and throw the weighted
arm 5 up to the position seen in Fig. 1ª, the pawl 6 wiping over the teeth of
the ratchet wheel 3 and taking a position as at first. The circuit is now broken
by the resiliency of the spring terminal tx, and the movement begins again, to
be repeated whenever the weighted arm descends to the proper extent. There
may be a spring cushion or buffer, 24, to limit the upward movement of the
weighted arm.
The time occupied by the weight in its ascent is only a very small fraction of
a second, and it is calculated to take place when the hair-spring is under tension,
so that the movement of the clock is not in any way interfered with thereby.
The inclined position of axis of the magnet M is important, in that it allows
the armature a to swing into its normal position by gravity, thus avoiding the
necessity of a spring, which varies in tension with time and in such a situation
would be very unreliable.
The weighted arm and ratchet device are not herein claimed per se, as they
have been employed before in a pendulum clock operated electrically; but they
have not before been employed and adapted for use in a clock having a balance-
wheel and escapement device, this employment and adaptation is herein claimed.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
1. An electric clock having a balance-wheel and escapement-device, a suitable
intermediate train, a weighted arm and ratchet-device for driving, an electro-
magnet and armature, and a spring contact-device for closing the circuit through
the magnet when the weighted arm descends, substantially as set forth.
2. An electric clock having a weighted arm and ratchet-mechanism for
operating the clock, an electro-magnet, the armature of which acts when attracted
to throw up said weighted arm, and a spring contact-device adapted to be closed
by the flexure of the spring terminal at the contact when the weighted arm
descends, substantially as set forth.
3. In an electric clock, the combination with the balance-wheel and escape-
ment-device, the driving arbor, the intermediate train, the weighted arm, and

page_text: the pawl and ratchet mechanism through which said weighted arm rotates said
driving arbor, of an electro-magnet, the swinging armature of said magnet,
and means between said armature and weighted arm, whereby the former
elevates the latter, substantially as set forth.
4. In an electric clock, the combination with the balance-wheel and escape-
ment-device, the driving arbor, the intermediate train, and the weighted arm and
pawl and ratchet mechanism for rotating the driving arbor, of an electric circuit
including a generator, the inclined electromagnet M, in said circuit, the sus-
pended gravity armature a, of said magnet, circuit-closing devices actuated by
said weighted arm, and means, between the suspended armature and said weighted
arm whereby the former, when attracted, elevates the latter, substantially as
set forth.
5. In an electric clock, the combination with the balance-wheel, hair-spring,
lever, escapement-wheel, driving arbor, and intermediate train, of the weighted
arm, and the pawl and ratchet mechanism through which said weighted
arm rotates the driving arbor, the electric circuit including a generator,
the electromagnet having its coils in said circuit, a rocking arbor, the armature
lever and armature suspended from said rocking arbor in such position that said
armature may swing across the poles of the magnet, an arm on said rocking
arbor carrying the circuit terminals, and means substantially as described for
bringing the circuit terminals together when the weighted arm descends, sub-
stantially as set forth.
6. In an electric clock, of the character described, the combination with the
inclined electro-magnet M, of a rocking arbor 18, above the poles of the magnet,
the armature lever 17, suspended from said arbor, the armature a on said lever-
the arm 20, fixed to said arbor and extending therefrom at an angle with the
lever 17, an open electric circuit including a generator and the coils of said
magnet, one of the terminals of said circuit being set in said arm 20, and the
other a spring, carried by said arm, substantially as set forth.
7. In an electric clock, the combination with the balance-wheel, hair-spring,
lever, escapement, escapement-wheel, driving arbor, and intermediate train, of
the ratchet wheel on said arbor, the sleeve 4 on said arbor, the pawl carried by
said sleeve, the weighted arm carried by said sleeve, the electric circuit, includ-
ing a generator, the terminals and of said circuit, the arbor 18, the arm 20,
on said arbor and carrying said terminals, the operating arm 22, carried by said
arbor, the pin 23, carried by the sleeve 4, and adapted to complete the circuit,
the inclined electromagnet M, in said circuit, and the armature a, suspended from
the arbor 18, substantially as set forth.
Dated this 8th day of December 1899.
STEPHEN WATKINS & GROVES,
Wolverhampton, Agents for the Applicant.