Improvements in Electric Motors for Self-winding Clocks.
Year: 1888

page_text: Improvements in Electric Motors for Self-winding Clocks.
A communication from abroad by DANIEL W. EDGECOMB, of Whitestone, Queens
County, New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool & 6 Bank Street, Manchester, both in
the County of Lancaster, and 323 High Holborn, in the County of Middlesex, 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 invention relates to rotating electric motors, and more especially to their
application to that class of self-winding clocks which are so organized that a circuit,
is completed through the rotary motor at proper intervals, say once an hour, and the
revolutions of the armature will wind the clock spring a predetermined amount, then
automatically sever the circuit-connections.
It is evident in such cases that, when the circuit through the motor is interrupted,
the tendency of the main spring which it has wound, is always to turn the motor-
arinature backward until the spring is unwound. To avoid this it has been customary
to apply to some part of the clock movement a dog or locking pawl which shall
prevent the spring from unwinding when the current through the electro magnet has
ceased. Such pawl or dog will arrest the armature in any position which it may
chance to occupy, and unless the motor is so carefully built and adjusted that it has
no dead points, it is liable to stop in such a position that upon the next closing of the
circuit, it will be unable to start, and in consequence the clock will presently stop.
The invention consists in dispensing with the usual dog or locking pawl applied to

page_text: the clock movement, and applying to the motor itself a device which arrests the
armature-drum in any of one or more predetermined positions when its current has
ceased. This consists of a lever or detent which may be thrown into the path of the
armature when the latter commences to revolve backward. This detent is so located
with reference to the electromagnets of the motor, that, when arrested, the armature-
drum shall stand in such a position that a forward movement will be insured upon
the next completion of the circuit.
The invention consists, therefore, not in removing dead or neutral points from the
motor but in causing the armature-drum always to stop, after performing its work,
in a definite predetermined position where there is no neutral or dead point to
interfere with its starting when the current is applied.
In the accompanying drawings, figure 1 is a top view or plan of a motor
equipped with a device of the character mentioned. Figure 2 is a- front elevation of
the same.
Referring to the figures, E represents the electric motor having an armature E¹.
This consists of the central post o carrying a series of bar armatures e¹ e¹, supported
upon a non-magnetic drum e. There is shown here but one magnet F through which
circuit connections are completed by means of the commutator spring hand a suitable
commutator H. When the circuit is closed through the magnet the armature tends
to revolve to the right in figure 2. Upon the pinion or shaft o there is carried a
flange o against the inner surface of which there presses an arm or detent u¹ which
is pivoted at u. This arm and flange may serve to better conduct the current from
the frame of the clock to the commutator of the motor. There is also carried by, or
attached to the arm u₁ an arresting arm u² which is designed to be thrown into the
path of the armature bars. As the armature is revolved this arm is thrown upward
out of the path of the armature-bars by reason of the friction between the arm u¹
and the flange o¹. When, however, the motor has ceased to operate and the spring
of the clock-work tends to turn the armature in the other direction, the friction
between the flange and the arm u³ throws the arm into the path of the armature-
bars as shown in Figure 2. When, therefore, the armature has turned back to a
predetermined position as shown in figure 2, it will be arrested. This position is
such that the armature-drum will start when the circuit is again closed through the
motor, as at this point there is no
"dead point'
to interfere, inasmuch as the
armature e is in a position to be attracted by the magnet when the circuit is again
completed.
"
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that I am aware of the Specification of
Letters Patent granted to J. G. Lorrain No. 10785 A.D. 1887 and I wish it to be
understood that I lay no claim to anything therein described and illustrated, but what
I claim is:
1. The combination with a clock-mechanism and an electric motor-armature for
winding the same, of a detent for arresting the armature in a predetermined
position with reference to the magnetic field of the motor upon its retrograde
movement, substantially as set forth.
2. In a self-winding clock having an electric motor with a rotating armature, the
combination with the armature-drum, of a pivoted arresting detent intercepting the
path of the armature-drum upon the backward movement of the same, and a frictional
connection between the armature-shaft and said detent for throwing the same out of
the path of the armature-drum during the forward movement of the latter, substantially
as set forth.
3. In a self-winding clock having a rotating electric motor, the combination with
the motor of an arresting device for the armature of the same stopping the armature
in a predetermined position other than a dead or neutral point upon the cessation of
the winding, substantially as set forth.
4. In a self-winding clock-mechanism having a rotating electric motor for winding

page_text: the same; the combination with the driving spring of the clock tending to normally
reverse the direction of rotation of the motor upon the cessation of winding, of an
arresting device acting in conjunction with said spring to arrest the armature of the
motor in a predetermined position, other than a dead point of the motor, at the
cessation of the winding, substantially as described.
Dahi 07th danc Ammend 1000
WM. P. THOMPSON & Co.,
Agents for the Applicant.

page_text: County, New York, United States of America.
1, WILLIAM PHILLIPS THOMPSON, F.C.S., M.L.M E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool & 6 Bank Street, Manchester, both in
the County of Lancaster, and 323 High Holborn, in the County of Middlesex, Civil
Engineer, do hereby declare the nature of this invention and in what manner the
same is to he performed, to be particularly described and ascertained in and by the
following statement :-
The invention relates to rotating electric motors, and more especially to their
application to that class of self-winding clocks which are so organized that a circuit
is completed through the rotary motor at proper intervals, say once an hour, and the
rovolutions of the armature will wind the clock spring a predetermined amount, then
automatically sever the circuit-connections.
It is evident in such cases that, when the circuit through the motor is interrupted,
the tendency of the main spring which it has wound, is always to turn the motor-
armature backward until the spring is unwound. To avoid this it has been customary
to apply to some part of the clock movement a dog or locking pawl which shall
prevent the spring from unwinding when the current through the electro magnet has
ceased. Such pawl or dog will arrest the armature in any position which it may
chance to occupy, and unless the motor is so carefully built and adjusted that it hus
no dead points, it is liable to stop in such a position that upon the next closing of the
circuit, it will be unable to start, and in consequence the clock will presently stop.
The invention consists in dispensing with the usual dog or locking pawl applied to

page_text: the clock movement, and applying to the motor itself a device which arrests the
armature-drum in any of one or more predetermined positions when its current has
ceased. This consists of a lever or detent which may be thrown into the path of the
armature when the latter commences to revolve backward. This detent is so located
with reference to the electromagnets of the motor, that, when arrested, the armature-
drum shall stand in such a position that a forward movement will be insured upon
the next completion of the circuit.
The invention consists, therefore, not in removing dead or neutral points from the
motor but in causing the armature-drum always to stop, after performing its work,
in a definite predetermined position where there is no neutral or dead point to
interfere with its starting when the current is applied.
In the accompanying drawings, figure 1 is a top view or plan of a motor
equipped with a device of the character mentioned. Figure 2 is a front elevation of
the same.
Referring to the figures, E represents the electric motor having an armature E¹.
This consists of the central post o carrying a series of bar armaturos e¹ e¹, supported
upon a non-magnetic drum e². There is shown here but one magnet F through which
circuit connections are completed by means of the commutator spring hand a suitable
commutator H. When the circuit is closed through the magnet the armature tends
to revolve to the right in figure 2. Upon the pinion or shaft o there is carried a
flange o against the inner surface of which there presses an arm or dotent which
is pivoted at u This arm and flange may serve to better conduct the current from
the frame of the clock to the commutator of the motor. There is also carried by, or
attached to the arm u² an arresting arm a³ which is designed to be thrown into the
path of the armature bars. As the armature is revolved this arm is thrown upward
out of the path of the armature-bars by reason of the friction between the arm u¹
and the flange o¹. When, however, the motor has ceased to operate and the spring
of the clock-work tends to turn the armature in the other direction, the friction
between the flange and the arm u' throws the arm u³ into the path of the armature-
bars as shown in Figure 2. When, therefore, the armature has turned back to a
predetermined position as shown in figure 2, it will be arrested. This position is
such that the armature-drum will start when the circuit is again closed through the
motor, as at this point there is no "dead point" to interfere, inasmuch as the
armature e is in a position to be attracted by the magnet when the circuit is again
completed.
Other forms and arrangements of arresting devices than that shown may be devised
and employed without departing from the spirit of the invention, but it will be
understood that the fundamental feature of the invention is the arresting of the
armature-drum in such a position with reference to the magnetic field that upon
again closing the circuit, it shall not be at a dead point.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is :-
1. The combination with a clock-mechanism and an electric motor-armature for
winding the same, of a detent for arresting the armature in a predetermined
position with reference to the magnetic field of the motor upon its retrograde
movement.
2. In a self-winding clock having an electric motor with a rotating armature, the
combination with the armature-drum, of a pivoted arresting detent intercepting the
path of the armature-drum upon the backward movement of the samo, and a frictional
connection between the armature-shaft and said detent for throwing the same out of
the path of the armature-drum during the forward movement of the latter, substantially
as set forth.
3. In a self-winding clock having a rotating electric motor, the combination with
the motor of an arresting device for the armature of the same stopping the armature

page_text: in a predetermined position other than a dead or neutral point upon the cessation of
the winding.
4. In a self-winding clock-mechanism having a rotating electric motor for winding
the same; the combination with the driving spring of the clock tending to normally
reverse the direction of rotation of the motor upon the cessation of winding, of an
arresting device acting in conjunction with said spring to arrest the armature of the
motor in a predetermined position, other than a dead point of the motor, at the
cessation of the winding, substantially as described.