IMPROVEMENTS ON ELECTRO-MAGNETIC CLOCKS, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO MECHANICAL CLOCKS
Year: 1869

page_text: LETTERS PATENT to John Matthias Augustus Stroh, Mechanician, of
Twenty-nine, Toliners Square, Hampstead Road, Loudon, County
of Middlesex, for the Invention of "IMPROVEMENTS ON ELECTRO-MAGNETIC
CLOCKS, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO MECHANICAL
CLOCKS."
Sealed the 3rd December 1869, and dated the 18th October 1869.
COMPLETE SPECIFICATION filed by the said John Matthias Augustus
Stroh at the Office of the Commissioners of Patents, with his
Petition and Declaration, on the 18th October 1869, pursuant to
the 9th Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
MATTHIAS AUGUSTUS STROH, Mechanician, of Twenty-nine, Tolmers
Square, Hampstead Road, London, County of Middlesex, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS ON
ELECTRO-MAGNETIC CLOCKS, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO
MECHANICAL CLOCKS," and have petitioned Her Majesty to grant unto me,
[Price 8d.]

page_text: my executors, administrators, and assigns, Her Royal Letters Patent for
the same, and have made solemn Declaration that I am the true and first
Inventor thereof.
NOW KNOW YE, that I, the said John Matthias Augustus Stroh, do
hereby declare that the following Complete Specification, under my
hand and seal, fully describes and ascertains the nature of the said
Invention, and in what manner the same is to be performed, in and
by the following statement :-
The first part of my Invention relates to a new construction of clocks,
in which the pendulum is employed for the production of magneto-
electric currents for the purpose of communicating motive power to a
number of other clocks in connection by means of an electric circuit with
the said clock, which I will call the driving clock.
Figs. 1 and 2 are front and side elevations of a driving clock, similar
letters of reference indicating corresponding parts in the two Figures.
This clock has, like an ordinary clock, a weight, multiplying wheels,
escapement, and pendulum. For the usual pendulum bob is sub.
stituted one or more hollow coil or coils of insulated wire L oscillating
over the pole or poles of a permanent magnet M, or over the similar
poles of two magnets. An electric current is produced at each oscilla-
tion of the pendulum, which current is in one direction when the coil
passes from left to right, and in the opposite direction when it proceeds
from right to left. The counter action exerted by the magnets on the
coils renders it necessary to apply a heavier weight to the train, and as
in this case an escapement of any of the usual constructions would be
subject to greater wear from the friction of the teeth of the scape wheel
on the pallets I have devised the following method by which the
friction is wholly confined to the centres on which the pallets move:-
Fig. 1, A is the scape wheel; B, B, the pallets with their pivots working
in holes at each end of the pallet frame C which is fixed on the arbor
carrying the fork K' connecting it with the pendulum K. The spiral
springs D, D, on the axis of the pallets are for the purpose of restoring
them to their normal positions when released by the scape wheel. At
each beat or oscillation of the pendulum a tooth of the scape wheel
comes in contact with the face of a pallet, and after giving an impulse
to the pendulum the pallet on its withdrawal from the tooth of the
scape wheel will spring back into its normal position. Each pallet is
brought into action alternately, and as the rolling friction between the

page_text: teeth and pallets is very inconsiderable the friction is confined to the
pivots, and the wear is reduced to a minimum.
My second improvement consists of several contrivances for auto-
matically regulating a clock which is in mechanical or electrical
connection with a distant regulator, and which may be applied to the
driving clock of any number of other clocks in electrical communication
therewith. For this purpose an auxiliary pendulum K, Figs. 1 and 2,
mounted so as to permit it to slide up or down is placed parallel to the
governing one L, and oscillates with it by means of the forks attached
to K. The upper end is attached to an oscillating beam H by means of
a steel spring I which passes through a small hole in the pallet arbor;
to the other end of the beam a counterpoise weight J is attached. On
the axle of the beam H a crank G is fixed, and to it a rod F having a
hole F to fit the point of a cam E mounted on the arbor which carries
the minute hand. The positions of the wheels of the train are indicated
by dotted lines. The action of this arrangement is that at a certain
time the cam E will arrive at the position indicated in the Drawing, and
by special means to be herefter described the rod F is forced for a
moment against the cam E, and if the time of the driving clock
corresponds with that of the regulating clock no alteration of the
regulating pendulum or the parts connected with it will take place,
but if the driving clock is slower than the regulator when the rod F is
pulled towards the cam only the lower edge of the hole in the rod F
will touch the cam E, and by its wedge shape will draw the rod F' down
and by means of the crank G and beam H will pull the regulating
pendulum K up and shorten it, thus increasing its going rate. The
reverse takes place when the driving clock is faster than the regulator.
Instead of shortening or lengthening the auxiliary pendulum the
length of the pendulum itself may be varied by the same means, but
I consider the mode above described to be preferable.
Fig. 3 is another mode of altering the rate of a driving clock which
may be employed instead of the secondary or regulating pendulum.
N is part of the frame of a driving clock, and O, O, are projections upon
it, to which the suspension spring of the pendulum is fixed; N', N¹¹, are
guides fixed on the frame N to receive the slide P and to allow the same
to slide up and down, and thereby to lengthen and shorten the suspension
spring without altering the position of the pendulum. The beam H
connects the slide P to the regulating rod F, shown in Figs. 1 and 2.

page_text: The above-mentioned methods of regulation are equally applicable
to ordinary pendulum clocks, and to clocks with a magneto-electric
pendulum.
My third improvement consists in certain methods of effecting the
regulation of any number of clocks by means of a single regulating
clock, it being understood that the regulator possesses one of the
usual contrivances for the momentary completion of the circuit con-
necting it with the other clocks which are to be regulated by it at
certain intervals of time, say every hour, or any other periodical interval.
Each clock to be regulated must possess a maintaining power, whether
.it be in electric communication with telegraphic clocks, or acting
independently as an ordinary clock.
When the communication from the regulator to the clock to be
regulated is effected by means of electricity I employ either of the fol-
lowing methods -Fig. 4, E is a cam formed by a disc fixed on the arbor
of one of the wheels of the train, having a notch on its edge indicated
by F, and attached to it is a collar Q having a screw e near its edge,
which passes through a slot in the rod R, one end of which is fixed by
means of a screw to the pondulum rod S; the link T connects the
screw and rod F with the pendulum rod S. U is a frame which is
fixed to the frame of the clock; on its upper side an electro-magnet N
is fixed, the coils of which are in circuit with the distant regulator, and
by means of screws the pendulum S and lever V are loosely attached.
W is an armature working on pivots having a lever X; the rod F com-
municates with the beam H, Fig. 1. By the rotation of the arbor
carrying the disc E and collar Q the screw e which is placed excentrically
on its side will pull by means of the rod R the upper part of the
pendulum rod S; its upper end coming in contact with the pin Y will
cause the rod V to deflect until it passes the pin Y, when the rod V
will drop and its lower end rest on the end of the lever X connected
with the armature, and thereby on the return of the pendulum its upper
end will come into contact with the pin, which will retain it in the
position indicated by the dotted lines Z. The notch in the disc E will
arrive at the position indicated in the Drawing at a moment corre-
sponding to a certain time of the clock, say twelve o'clock, and at
exactly or nearly this moment the electric circuit will be completed by
the distant regulating clock; this will cause the magnet to attract the
armature W; the lever X will be depressed and release the rod V, and

page_text: consequently the pendulum S, which will by its momentum swing to
the position indicated by the dotted lines Z¹, carrying with it the con-
necting piece T and the screw F¹ which will enter the notch, and if the
time of the two clocks correspond no alteration in the position of
the beam H, Fig. 1, will take place; but if the rate is slower than the
regulating clock the screw F will only touch the upper side of the
notch in the disc E when it is drawn against it, and thereby pull
the rod F down and the regulating pendulum up, thus increasing its
going rate; the reverse action taking place when the clock is faster
than the regulator.
Fig. 5 represents another means of effecting the same purpose by
electro-magnetism which is more simple than the preceding, but does
not admit of so great a limit of adjustment. E is a disc fixed on the
arbor of one of the train wheels of a clock. a, a, are the poles of an
electro-magnet (the coils of which are in circuit with the distant
regulator) fixed thereon and revolving with it; b is a lever of soft iron
loosely attached to the rod F which forms the connection with the
beam H (Figs. 1 and 2). During the revolution of E the lever bis
merely moved up and down without affecting the rod F, but if at the
predetermined moment when the electric current from the distant
regulating clock is transmitted through the line, and the lever bis in
contact with both poles of the electro-magnet a, a, no action on the
rod F results, but should the lever b only rest upon one of the poles a, a,
it will form a fulcrum, and the other pole attracting the lever will
occasion the motion of the rod F. When the communication between
the regulator and the clock to be regulated is effected by mechanical
means either a striking movement or a substitute for it may be employed
in the former. The crank n, Fig. 1, may be connected on one side with
the rod F in connection with the beam I, and on its other end by means
of wires and cranks with a lever acted upon by a pin in the locking
plate of the striking movement of the regulator. Should it be required
to apply any of these methods of regulating to clocks already constructed,
if the maintaining power be too weak, it may be necessary to introduce
an auxiliary force to supply the deficiency.
My fourth improvement consists of a method of propelling a train of
wheels connected with the hands of a clock by means of the continued
rotation of one or more magnetized needles acted upon by galvano-
metric or other electro-magnetic coils, through
which alternately

page_text: inverted electric currents are transmitted from a driving clock. By
means of this contrivance the escapements employed in telegraphic
clocks as hitherto constructed are dispensed with, and the motions of the
hands are perfectly continuous. One advantage of this new construction
is that a second can never be gained or lost; the clock may stop
altogether from the stoppage of the driving clock or the interruption
of the circuit, but as long as it remains in motion it must indicate the
time of the driving clock accurately.
Figs. 6 and 7 represent two of the forms employed for this purpose.
Fig. 6 is in form and construction similar to a galvanometer. A
quantity of insulated wire is wound on a frame d; the space in the
middle thereof permits the maguetized needle f to rotate; the said
needle is mounted on an arbor g, which carries a pinion gearing with
a crown wheel h in connection with the train which communicates its
motion to the hands.. The alternately inverted currents proceeding
from a driving clock, such as described in my first improvement, are
caused to pass through the coil of insulated wire on the frame d, and
provided the needle f has been strarted with the proper velocity it will
be propelled for half a revolution by the current which is produced
while the pendulum of the driving clock is going from right to left,
and another half revolution while the pendulum passes from left to
right, thus describing a whole circle in one second if half a second is
required for each beat of the pendulum. The time when the needle f
after each half revolution arrives at a position at right angles with the
wire of the coil d corresponds exactly or nearly so with the moment
when the pendulum of the driving clock has arrived at its greatest
deflection from the perpendicular. It is advantageous to fix on the
arbor a second magnetized needle parallel with the first with its poles
oppositely directed outside of the coil in order that the combination
may be astatic.
Instead of the galvanometer coil with the needle rotating inside the
insulated wire may be wound on a soft iron ring or disc, as shown at
Fig. 7, and two magnetized needles may be fixed on the same arbor
parallel to each other, with their poles similarly directed one above and
one below the coils. By the action of the currents the ring or disc is
temporarily magnetized, changing its polarity at each inversion, and the
needles are thereby propelled in the manner above described.

page_text: Having now described the nature of my said Invention, and in what
Danner the same is to be performed, I hereby declare that I claim as
follows:-
Firstly. The escapement with moveable pallets represented in Fig. 1
for the purpose of diminishing the friction consequent on the employ-
ment of a heavier weight to the train.
Secondly. Altering the vibrations of a pendulum by means of a cam
placed on one of the arbors of the train of a clock, the cam being
brought into gear periodically by a motion communicated electrically
or mechanically from a distant regulator. A mode of effecting this is
described and represented.
Thirdly. Communicating motion to the traiu of wheels of a clock by
means of the continued rotation of one or more magnetized needles or
bars within or in proximity to a galvanometric or electro-maguetic
coil, this rotation being effected by electric or magneto-electric currents
alternately in opposite directions, the recurrence of which is regulated
by a distant driving clock.
In witness whereof, I, the said John Matthias Augustus Stroh,
have hereunto set my hand and seal, this Eighteenth day of
October, in the year of our Lord One thousand eight hundred and
sixty-nine.
JOHN MATTHIAS AUGUSTUS STROH. (L.S.)