IMPROVED SYNCHRONIZING AND TIME SIGNALLING MECHANISM FOR CLOCKS
Year: 1883

page_text: LETTERS PATENT to William Samuel Harrison of Huntingdou Street, Barnsbury
in the County of Middlesex, Clockmaker and Electrician. for an Invention of
PROVISIONAL SPECIFICATION left by the said William Samuel Harrison at
the Office of the Commissioners of Patents on the 20th July 1883.
WILLIAM SAMUEL HARRISON of Huntingdon Street, Barnsbury in the County
of Middlesex, Clockmaker and Electrician "IMPROVED SYNCHRONIZING AND TIME
SIGNALLING MECHANISM FOR CLOCKS."
The object of the present invention is to provide improved means whereby any
number of clocks of any construction may be accurately synchronized by an
impulse transmitted by electricity, air, or liquid, from a motor clock, and be
corrected to minutes and seconds for any error of say 5-minutes or more, either
fast or slow; and in cases where line wires for telephonic; telegraphic, or other
signalling purposes already exist, to enable the comparatively feeble impulses
passing through such wires, to be utilized for the purpose of setting in motion the
time signalling and synchronizing mechanism without in any way detracting from
the usefulness of the said wires for ordinary telegraphic or other purposes; before
or after the synchronizing or time signalling impulse has been transmitted, or
breaking the circuit between such wires and the electrical instruments on them.
To this end the invention consists in a separate piece of clockwork mechanism
driven by the stored energy of a wound spring or a falling weight, which may be
readily attached to the clock to be synchronized, and which-mechanism is so
constructed and arranged with respect to the works of the said clock, as first to be
automatically "set" ready for the receipt of the time signal, by the rotation of the
hour or minutes wheel or other convenient part of the clock, and then to be
liberated by the electrical or other impulse transmitted from a distance. Thus
each clock automatically prepares its synchronizing mechanism to receive the time
signal, or electrical or other impulse from the notor clock, and the only work
required to be performed by the said electrical or other impulse, is to discharge a
light lever or trigger to unlock the synchronizing or time signalling mechanism and
set it in motion.

page_text: The invention also consists in a novel arrangement of synchronizing arms which
when set in motion by the separate mechanisin above mentioned are caused to move
rapidly in opposite directions through a large angle and catch the minute hand as
they sweep round, bringing it instantly to the hour, and immediately afterwards
rising clear of its extremity, without in any way interfering with the clock
movement.
11A 1
The wide effective range of these synchronizing arms enables errors of 5 minutes,
or even more, fast or 'slow, to be corrected, and consequently clocks of cheaper
make can be used; whereas in electrical synchronizers as at present constructed
the effective range of the synchronizing arms is very slight, and the arms are liable
to miss the hand altogether if the error in time be over a minute or so in either
direction; thus necessitating the employment of rather expensive clocks.
These electrical synchronizers moreover require a very large battery power and
their arms or fingers act with great violence upon the hand to be moved, the result
being that not infrequently the teeth of the movement are injured. The residual
magnetism in the coils is also very considerable in these instruments and therefore
considerable force is required to overcome such residual magnetism, but by my
invention the coils are small, and the residual magnetism slight, and the clock itself
acting on a small spring easily overcomes what residual magnetism there may
be and forcibly detaches the armature from the coils, and sets it again ready for
action.
T
i .
By this mode of effecting the synchronizing of clocks, no derangement, of the
mechanism is possible by a current of excessive power, or by residual magnetism,
while a current of feeble strength.is sufficient for the purpose required.
The invention also relates to novel means for switching the coils out of circuit
simultaneously with the synchronizing movement thus setting free the line wires
for other purposes when so used without retaining any unnecessary resistance in the
circuit.
19.
The invention also relates to novel means for synchronizing the seconds hands of
clocks receiving electrical or equivalent impulses from a regulating motor clock at a
distance, and to means for enabling the nett cumulative deviation of a clock from
the true time during a given period, and for which it has been corrected, to be easily
ascertained and registered.
The preparation.or setting of the separate synchronizing mechanism, by the clock
itself may be effected by means of a pin on the minute or hour wheel actuating a
lever which unlocks the train, clears the armature from the coils, and locks the, fly
of the synchronizing mechanism until the receipt of the time signal, whereupon the
armature releases the train, the synchronizing arms sweep together, and set the
hands accurately to time, and the armature coils are switched out of circuit. They
may then be switched into circuit automatically, or by means of a cord or chain
operated by hand on receipt of a warning signal, ready for the next synchronizing
impulse.
'
4
The wheels in the train are so proportioned and arranged as to set the clock
twice for every revolution, and 'two pins on a disc suffice to raise a bell hammer and
keep it raised until the fly is released by an electro,magnet acting on a lever, when
the hammer will fall and, strike, a bell. These two pins or their equivalent also
serve to actuate a lever and cut the coils out of circuit simultaneously with the
synchronizing of the clock, to save the resistance of these coils on wires used for
telegraphic or other electrical purposes as above described..
".
The locking device of the separate synchronizing mechanism may be very similar
to that used in striking clocks, except that its final release or discharge is effected
by the armature lever..
For synchronizing the seconds hand and making the clock indicate the true time
to seconds, I disengage, the seconds arbor from the seconds hand by means of a
lever operated by a separate action of the synchronizing mechanism.
4
A lever fitted with rollers lifts the seconds pipe which carries the seconds hand
from the seconds. arbor on which is fixed a crown wheel turning with the said

page_text: arbor, and by means of a heart-piece fixed on the said pipe the seconds hand is
moved backward and forward as required to synchronize the clock to seconds, a
light spiral spring serving to bring the parts again in contact when the lifting
lever is released.
A pin fixed to the pipe is adapted to fall into the teeth of the crown wheel
after this synchronizing movement has been effected, and puts the parts in gear
again.
1
i.
The smooth action of the heart-piece is ensured by its resting when in the
raised position, upon two rollers carried by the lifting lever and so placed that their
axes are in line, and that a line drawn through their axes cuts the axis of the
seconds arbor at right angles.
:
=
To enable the clocks to be regulated by hand, I form the pin which passes
through the arbors of the minute and seconds hands with an extension in the
form of a small pointer or index hand and arrange it so that in setting the clock,
the said pointer or hand will be in line with the minute hand at a certain hour,
and after the hand has been shifted by the synchronizing arms during a given
period the difference in direction of the smaller and larger hands will be a measure
of the cumulative deviation, from true time. It will then only be necessary to
note where the long hand is, and to move it over the dial into line with the
index hand above mentioned to read off the extent of the nett cumulative
error during the said period, and enable the pendulum to be regulated accordingly.
By the above improvements clocks intended to be synchronized can be made.
cheaper, stronger, and of greater durability than heretofore.
All striking clocks to which the above mechanism is applied will be caused to
strike the first blow of the hour simultaneously, and non-striking clocks may have
a time gong fitted which will indicate true time within one tenth of a second.
The stored energy of the main-spring of the separate synchronizing and time
signalling apparatus will suffice for the daily regulation of a clock for more than
a month, so that a minimum of attention will be necessary to keep the apparatus
in going order, and no derangement of or interference with the clock movement,
except for regulating the seconds hand, will be necessary.
The time signals may be transmitted by the impulse of air, water, or liquids,
such as paraffin and benzine:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and of an
Order of the Lord Chancellor filed by the said William Samuel Harrison in
the Patent Office on the 11th February 1884...
WILLIAM SAMUEL HARRISON, of Huntingdon Street, Barnsbury, in the County
of Middlesex, Clockmaker and Electrician, "IMPROVED SYNCHRONIZING AND TIME
SIGNALLING MECHANISM FOR CLOCKS
"
The object of the present Invention is to provide improved means or mechanism
applicable to clocks of any construction whereby such clocks may-be accurately.
set to time or synchronized upon receipt of a time signal or impulse transmitted by
electricity, air, or liquid from a motor or regulator clock at a distance and common
to any convenient number of clocks to be synchronized.
The improved means consist in an arrangement of clockwork mechanism
(independently driven or actuated in its synchronizing operation by the stored
energy of a wound spring or of its equivalent such as a falling weight) which can
be readily and detachably attached to any clock to be synchronized in such a
manner with relation to the works or movement thereof so that it shall be at any
predetermined regular periods automatically unlocked or prepared by some part of
such works or movement and set ready for the receipt of the electrical or other
time signal or impulse from the regulator clock, upon the receipt of which the
synchronizing mechanism is finally liberated, when it has its instant independent
action and operation by means of which the hands of the clock are set to indicate
the true hour or time.
The Invention comprises as a material feature in cases where electricity is used
for transmitting the time signals or impulses from the regulator clock and in which
ordinary line wires are used for transmitting such signals, novel means for
automatically switching the coils of a small electro magnet into circuit with the
line wire for the receipt of the time signal by the said operation of the clock in
preparing or setting the synchronizing mechanism ready for the receipt of the time
signal, or by the consequent but independent operation of the synchronizing
mechanism in being thus prepared and set, and for switching the said coils out of
circuit with the line wire simultaneously with and by the said independent operation
of the synchronizing mechanism, or by the operation of the clock movement in again
locking the synchronizing mechanism after its independent operation, thus setting
free the line wires for other purposes when so used without retaining the resistance
of the coils in the circuit.
Thus, according to the present Invention, each clock to which the improved
synchronizing mechanism is adapted, automatically prepares such mechanism to
receive the electrical or other impulse constituting the time signal from the motor
clock, and the only work required to be performed by such impulse is to discharge
means such as a light. lever or trigger to finally liberate the synchronizing
mechanism and allow it to have its independent synchronizing action.
The improvements also comprise as a material feature a novel arrangement of
synchronizing arins or levers which are directly actuated by the independent
operation of the synchronizing clockwork, and are thereby caused to rapidly sweep
through a large angle in opposite directions and towards each other with a
comparatively powerful but gentle action until they are in line, the one or other of
them gently catching the minute hand as they sweep round and bringing it
instantly to indicate the exact hour, and without in any way interfering with the
clock movement, and immediately after which, the arms are caused, by a reversing
motion adapted to the synchronizing mechanism, to return to their normal positions
clear of the hand.

page_text: The direct action of the synchronizing clockwork mechanism upon these
synchronizing arms allows of a wide, effective range of movement being given to
them and enables large errors of deviation, of 5 minutes or even more, fast or slow,
being easily corrected, without injuring the dial motion, and consequently clocks
of cheaper make can be used; whereas, in electrical synchronizing mechanism as
hitherto constructed in which arms are actuated by the action of an electro magnet,
the effective range of the synchronizing arms is very slight, and the arms are liable
to miss the hand altogether if the deviation from a true indication be over a
minute or so, fast or slow, thus necessitating the employment of rather expensive
clocks. Such electrical synchronizing instruments, moreover, require a very
considerable battery power, and their arms act with great violence upon the hands
to be moved, with the result, that, at times; the teeth of the wheels of the clock
movement are injured. The residual magnetism in the coils in these instruments
is also a frequent source of inconvenience, and considerable force is required to
overcome it, but the coils used with my improved electrical synchronizing
mechanism, in which the arms are acted upon by the independent operation of the
synchronizing clockwork, are small, as the electrical impulse has only. to discharge
the said light lever and the residual magnetism is slight, and the independent
action of the synchronizing clockwork, or the operation of the clock movement in
the manner hereinafter described, acting on a small spring, easily overcomes what
residual magnetism there may be, should the said light lever or armature not clear
itself from the coils, and detaches it therefrom, setting it again in position ready
for its action in preventing the final liberation' of the synchronizing mechanism
and its independent operation, until receipt of the time signalling iinpulse.
By this mode of effecting the synchronizing of clocks, no derangement of the
mechanism is possible by a current of excessive power; or by residual magnetism,
while a current of feeble strength is sufficient for the purpose required.
The Invention further relates to novel means to be used in combination with
and to be operated by the said synchronizing mechanism, for synchronizing the
seconds hands of clocks, to which such synchronizing mechanism is applied; and
to the combination of a bell, gong, or flashing signal with such synchronizing
mechanisin as is herein described, to cause the same to audibly or visually indicate
the true time within a small fraction of a second; and to means for enabling the
nett cumulative deviation of a clock from the true time during a given period for
which it has been corrected; to be registered and easily ascertained, for facility in
properly regulating the pendulum.
The Invention is illustrated on the accompanying drawings, in which, Fig; 1,
represents a rear elevation of the improved synchronizing mechanism, adapted to
be operated by electrical impulses received from the regulator clock, showing it in
its normal position ready, to be unlocked by the operation of the clock to which it
is adapted. Fig; 2, represents a similar view of the mechanism, showing it in the
position its parts assume when it has been unlocked by the operation of the clock,
and showing the coils of its electro-magnet as automatically switched into circuit
with the line-wire by the operation of the synchronizing mechanism consequent
upon its being set by the operation of the clock movement ready for the receipt of
the electrical time signal' or impulse. "In this Figure, the dotted position of the
armature indicates the position it assumes upon receipt of the time-signal through-
the coils of the electro magnet, and in, which position it liberates the fly of the
synchronizing clockwork, which then has its independent operation in effecting the
instant and true setting of the hands of the clock. Fig; 3, represents in dotted
lines the pitch lines of the wheel gearing of the synchronizing mechanism, and
which gearing is situated between and supported by two opposite parallel plates
the rear one of which is shown as removed in this Figure. Fig'; 4' represents a
plan view of the synchronizing mechanism, showing in full lines the normal position
of the synchronizing arms, and in dotted lines the position for correcting the hands
the operation of the mechanism causes them to assume. Fig; 5, represents'
sufficient of the dial- of an ordinary clock to illustrate the application of the

page_text: improved synchronizing mechanism thereto, illustrating its mode of operation upon
the minute hand.
The synchronzing mechanism illustrated in the above referred to Figures is
adapted only to operate upon the minute hand.
Fig; 6. is a front elevation, illustrating the additional mechanism used when the
synchronizing mechanism is adapted to a clock with a seconds hand, which it is
required shall be synchronized. Fig 7. is a side elevation of the mechanism
illustrated in Fig; 6.
The improved synchronizing mechanism is constructed with two trains of gearing,
both deriving their movement from a coiled spring within a case 1. The wheels
and pinions 2, 3, 4, 5, 6, 7, constitute one train, and operate the fly 8, and the
wheels and pinions 2, 3, 9, 10, 11, 12, 13, 14, constitute the other train, and operate
the synchronizing arms 15. The spindles of all the wheels and pinions are carried
by opposite front and back plates 16, 17. kept apart by pillars 89. The spindle 18;
connected to the spring within the case 1, projects through the plate 16, and is
squared at 19, and can be wound up through an aperture 20, in the dial 21, and it
is retained by a ratched 22, and spring pawl 23, The rear end of the spindle 24,
carries a locking disc 25, which has recesses at 26, and is provided on its face with
pins 27. The rear end of the spindle 28, also carries a locking disc 29, which is
notched at 30. The spindle 31, carries the fly 8, and its rear end carries a locking
disc 32, which has a pin 33, The spindles 34, 35, project through the plate 16, and
through the dial 21, which is spaced apart from the plate 16. by short pillars or
lugs 90, and on the face of the dial each spindle carries one of the synchronizing
arms 15. In the case of turret clocks, the arms 15, may be arranged at the rear of
the dial and operate on a false hand on the arbor of the minute hand for correcting
the indication of the latter. The plates 16, 17, also support a spindle 36, the rear
end of which carries a lever 37, provided with locking pins 38, 39, 40, which
respectively engage with the recesses 26, 30, and the pin 33, of the discs 25, 29, 32,
when the lever 37, is in its normal position; the front end of the spindle 36, carries
a wire, rod, or bar 41, or any equivalent connection which extends to the minute
wheel 42, or to the hour wheel, or to any convenient part of the movement of the
clock by which it can be operated at any desired regular periods.
43, represents the light lever or trigger hereinbefore referred to, and which is
centred at 44, and has a pin 45, which engages with a pin 33, and retains the fly 8,
of the synchronizing clockwork, after the pin 33, has escaped from the pin 40, and
the synchronizing clockwork has been unlocked by the operation of the clock, until
the time signal or impulse has been received, and which causes the lever 43, to shift
its position so that its pin 45, frees the pin 33, and thus finally liberates the fly
and allows of the independent operation of the synchronizing mechanism. In the
modification illustrated on the accompanying drawings, the lever 43, consists of the
armature of a small pair of electro-magnets 46, carried by a cock 47, screwed to
the plate 17, and through which the electrical time signals are received by the
connections 48, from the motor or regulator clock.
49, represents a switching lever, centred at 50, and having a toe 51, which
engages with the recesses 26, of the disc 25, and an extension (49), which makes
contact with one or other of the contact pieces 52, 53, insulated from the plate 17,
by ebonite at 54, The normal position of this lever is in contact with the piece 52,
in which position it is retained by the circumference of the disc 25, acting upon its
toe 51, and keeping the coils out of circuit with the line-wire until the clock
movement unlocks the synchronizing mechanism, when the disc 25, moves suffi-
ciently to allow of a light spring 55, throwing the toe 51, of the lever 49, into the
recess 26, which presents itself, and its extension (49) into contact with the piece 53,
when the coils will be in circuit with the line wire until the time signalling impulse
is received, and the synchronizing mechanism set free, when the further rotation of
the disc 25, will again move the lever 49, and throw the coils out of circuit with
the line wire.
•
When in its normal position (vide Fig 1.), the synchronizing mechanism is locked
"

page_text: by the pins 38, 39, 40, of the lever 37, and the armature 43, is clear of the coils of
the electro-magnet, and is in such a position as to lock the fly 8, after the train of
gearing has been unlocked and prepared and set by the operation of the clock.
This primary unlocking of the synchronizing clock work may be effected by means
of a pin 56, on the minute wheel 42, of the clock, if it is desired to synchronize the
clock every hour, or on the hour wheel if it is desired to synchronize it every
twelve hours, shifting the lever 41, 36, 37, from the position indicated in Fig 1. to
that indicated in Fig 2. It will be seen on reference being had to Fig 2. that this
movement of the lever 37, lifts its pins, 38, 39, 40, out of engagement with the
recesses 26, 30, and the pin 33, of the discs 25, 29, and 32, and unlocks the train
of synchronizing gearing from the control of the clock, leaving it only under the
control of the light lever, trigger, or armature 43, which is to receive the time
signalling impulse. The armature is kept in its normal position, until receipt of
the time signalling impulse, by a light spring 57, which may be lightly acted upon.
by the pins 27, on the disc 25, or by another pin projecting under the spring from
the lever 37. In the latter case, the operation of the clock, and in the former case,
the independent operation of the synchronizing mechanism, would effect the
clearance of the armature from the coils should there be any residual magnetism
in them, so that on the synchronizing mechanism being unlocked by the operation
of the clock, the fly 8, will be certain to be arrested by the pin 45, of the
armature 43, until the latter receives the time signalling impulse-which will
liberate the fly and allow of the instant independent operation of the synchronizing.
mechanism, which will cause the synchronizing arms to sweep together and catch
the minute hand and set the hands accurately to time as will be clearly seen on
reference being had to Figs 4 and 5.-
The coils may be automatically switched out of circuit with the line wire
simultaneously with the synchronizing of the clock, and by the operation of the
synchronizing mechanism, by the rotation of the disc 25, by its recesses 26, or
pins 27, acting upon the toe 51, of the lever 49, or this may be effected by the
operation of the clock in again locking the synchronizing mechanism by means of
the lever 37, directly actuating the lever 49, The coils may be automatically
switched into circuit with the line wire either by the synchronizing mechanism as
herein before described, that is by the operation of the disc 25, and spring 55, or by
the operation of the clock, through the medium of the lever 37, directly actuating
the lever 49, or the coils may be switched into circuit by means of a wire, cord, ur
chain depending from the hole 58, and operated by hand on receipt of a warning
signal to prepare for the synchronizing impulse.
In the modification represented on the annexed drawings, the wheels or gearing
in the synchronizing clockwork are so proportioned and arranged as to synchronize.
the clock twice for every revolution of the wheel 9., but this proportioning and
arrangement of the wheels or gearing is not essential and may be varied so long
as all the working parts are properly timed to operate in the manner herein
described.
When adapting the improved synchronizing mechanism to non-striking or to
other clocks, the pins 27, on the disc 25, may be further utilized to raise a bell
hammer 59, centred at 60, and keep it raised until the fly 8, is released as herein-
before described, when the hammer will fall and be caused by a spring 61, to
strike a bell 62, and audibly indicate the true time, or in lieu of a bell or gong for.
audibly indicating the synchronizing operation, an ordinary flashing signal may.
be caused to visually indicate it.
It will be noticed on reference being had to Figs; 4 and 5, that the gear 9 has
parts of its teeth cut away at 63, and that the spindle 35, and train of wheels 14,
13, 11, 10, 12, are operated upon by a spiral spring 64, tending to give a reverse.
motion to these wheels to that given to them by the spring within the case 1, and
that the spindle 65, has a pin 66, projecting through a semicircular slot 67, in the
plate 16, the object and effect of this arrangement is that after the synchronizing.
movement of the arms 15, is effected by the independent operation of the.

page_text: synchronizing mechanism, one of the parts 63, of the gear 9, comes opposite and
'disconnects itself from the gear 10, thus leaving the gearing 10, 11, 12, 13, 14, to
the sole control of the spring 64, which instantly reverses their movement, and
brings the synchronizing arms 15, from the synchronizing position shown in dotted
lines in Figs.
and 5, back to their normal position shown in full lines in these
Figures in which position they are arrested by a stop 91'
When applying the synchronizing mechanism to clocks having seconds hands,
'and it is wished to synchronize the seconds hands, and make the clock indicate true
time to seconds, I fit the seconds hand on a socket 68, carrying a heart shaped
cam 69, and a pin or knife edge 70, which is adapted to engage with or fall into
the teeth of a crown wheel 71, fixed on the seconds arbor 72; and on the front
end of the spindle 24; I fit a disc 73, having flanges 74, with intervening recesses
at opposite points 75, and between the spindles 24, 72, I pivot in a bridge
cock 76, a lifting lever 77, each end of which is forked and provided with small
rollers 78, 79, the former of which bear against the flanges 74, of the disc 73, and
have their normal position in the recesses 75, thereof, and the latter of which bear
in an opposite direction against the rear face of the heart cam 69. The edge of the
disc 73, may be forined with cam surfaces, or its face may be provided with
pins 80, and these cam surfaces or pins are so placed as to engage with the
arm 81, of a shifting lever centred at 82, on the face of the bridge cock 76, or
elsewhere, and the other arm of which lever carries a small roller 83. The normal
position of the lever 81, is indicated in Fig 6. in full lines, and it is retained in
this position by a light spring 84, bearing it against a stop 85.
The operation of the seconds synchronizing. mechanism is as follows. Simul-
taneously with the commencement of the independent operation of the synchronizing
mechanism herein before described as applicable to the minute hand of a clock, the
rotation of the disc 73, by means of its cam-acting flanges 74, causes the lifting
lever 77, to shift its position, and disengage the pin or knife edge 70, on the socket
of the seconds hand, from the crown wheel 71, on the seconds arbor 72, and
immediately thereafter the cams or pins 80, on the disc 73, actuate the shifting
lever 81, and cause its lower ärm and roller 83, to travel towards the centre of
notion of the seconds hand, and in its said travel, the roller 83, comes against the
edge of the heart cam 69, turning it backwards or forwards (depending upon the
position of the seconds hand, which, as an example, is illustrated in Fig; 6, as
some twenty seconds slow,) until the roller 83, falls into a locking notch 86, formed
in its edge at its smallest radius, thus causing the seconds hand to point to true
time at the cessation of the operation of the synchronizing mechanism, simul-
taneously with which, a light spiral spring 87, encircling the seconds arbor, and
contained within the seconds socket between the collet 88, and the end of the
socket 68, causes the rollers 78, of the lever -77, to fall into the recesses 75, in the
dise flange 74, allowing of the engagement of the pin or knife edge 70, with
the crown wheel 71, on the seconds arbor, putting the seconds hand in gear with
the clock movement again, and the spring 84, also causes the roller 83, of the
lever 81 to disengage itself from the peripheral notchi 86, in the heart cam 69, so
that, simultaneously with the cessation of the operation of the synchronizing
mechanism, the clock can start with all its hands indicating true time.
The smooth action of the heart piece 69, when in its disengaged position, and
when being turned by the lever 81, is ensured by its being borne by the spring 87,
against the rollers 79, of the lifting lever, which rollers are so placed that their
axes are in line, and that a line drawn through their axes will intersect the axis of
the seconds arbor at right angles.
The means herein before referred to for enabling the nett cumulative deviation of
a clock from true time during a given period for which it has been corrected to be
registered and easily ascertained so as to facilitate the proper adjustment of the
length of the pendulum, consist of a pin or pins 89, passing through the arbor, or
arbors, of the minute, or minute and seconds hands, and each of which pins is forined
as a pointer or index finger, and which I arrange in setting the clock so that the

page_text: said pointers or fingers will be in line with the minute and seconds hands at a
certain hour, and after the hands have been shifted by the synchronizing arms and
mechanism during a given period in correcting their errors of indication, the
difference in direction of the hands and pointers will be a measure of the
cumulative deviation from. true time; and it will then only be necessary to note
where the minute hand is, and to move it over the dial into line with its index
finger, to read off the extent of the nett cumulative error during the said period,
and enable the pendulum to be regulated accordingly.
By the above described improvements clocks intended to be synchronized can be
made cheaper, stronger, and of greater durability than heretofore.
All striking clocks to which the above mechanism is applied will be caused to
strike the hour simultaneously and non-striking clocks may be caused to audibly
or visually indicate true time within a small fraction of a second.
The mainspring of the synchronizing mechanism may be made of such a size as
to suffice for the daily regulation of a clock for a considerable period, so that a
minimum of attention will be necessary to keep the apparatus in going order, and
no derangement of or interference with the clock movement, except for regulating
the seconds hand, will be necessary.
In lieu of the time signals or impulses being transmitted by electricity, as
herein before described, they may be transmitted by the impulse of air, water, or
liquids such as paraffin and benzine, being caused to act by any suitable connections
upon the said light lever or trigger.
Having thus particularly described and ascertained the nature and objects of my
said Invention and in what manner the same is to be or may be performed or
carried into practical effect, I would observe in conclusion that what I consider to
be novel and original and therefore claim as constituting the Invention secured to
me by the hereinbefore in part recited Letters Patent is;-
In mechanism applicable to clocks of any construction for synchronizing such
clocks upon receipt of a time signal or impulse transmitted by electricity, air, or
liquid from a motor or regulator clock at a distance.
1. The combination of the lever 41, 37, 36, with its locking and unlocking details,
or of equivalent means which can be automatically operated at any predetermined
regular periods by some part of the works or movement of the clock to which the
mechanism is applied for partially unlocking or preparing and setting the
synchronizing mechanism ready for the receipt of the time signal; with the light
Jever, trigger, or armature 43, with its locking details, or of equivalent means
operated by the receipt of the time signal or impulse and thereupon finally
unlocking the synchronizing-mechanism; and with an arrangement of clockwork,
which, until the receipt of such time signal or impulse, is under the control of both
the clock, and of the means or time signalling details which receives the said
impulse, and which, when, released from such control is independently and
mechanically actuated in its synchronizing operation by the stored energy of a
coiled spring or of its equivalent; and with a pair of synchronizing arms or levers
acting upon the hand to be corrected or its equivalent, and directly actuated by
the independent operation of the synchronizing clockwork; and with means for
instantly reversing the synchronizing arms immediately upon the cessation of the
operation of the synchronizing mechanism; or of equivalent parts or means
operating substantially in the manner hereinbefore described, and in like manner
without in anyway interfering with the clock movement.
2. The further combination with such means and mechanism, when applied to
clocks having seconds hands which it is required shall be synchronized; of the
disc 73, flanged, recessed, and formed with cams or pins; the lifting lever 77, and
its connections; the lever 81, and its connections; the socket 68, carrying the
seconds hand, the heart shaped cam 69, and the pin or knife edge 70, and the
inner spring 87; or of equivalent means operated by the synchronizing clockwork
for lifting the seconds hand out of and into engagement with the clock movement,

page_text: and for shifting the seconds hand to its true indication when thus out of
engagement, substantially as herein before described.
"
3. The further combinations, firstly with such means and mechanism as are
claimed in claim 1, and secondly with such means and mechanism as are claimed
in claim 2, in cases in which electricity is used for transmitting the time signals,
and in which line wires used for telegraphic, telephonic, or other purposes are used
for transmitting such signals;-of a small electro-magnet for imparting the impulse
to the said lever or armature for finally unlocking and liberating such clock work
synchronizing mechanism; and of the lever 49, spring 55, contacts 52, 53, and
their respective connections; or of equivalent means for automatically switching
the coils of the electro-magnet into circuit with the line wire for the receipt of the
time signal, either by the operation of the clock, (through the medium of the lever 37,
directly acting upon the lever 49) in preparing or setting the synchronizing
mechanism ready for the receipt of the time signal, or by the consequent but
independent operation of the synchronizing mechanism (through the medium of
the disc 25, and by the aid of the spring 55,) it being thus prepared or set, and for
switching the coils out of circuit with the line wire sinultaneously with and by
the said independent operation of the synchronizing mechanism, (through the
medium of the disc. 25,) or by the operation of the clock (through the medium of
the lever 37,) in again locking the synchronizing mechanism after its independent
operation, for setting free the line wires for other purposes when so used without
retaining the resistance of the coils in the circuit, substantially as hereinbefore
described.
4. In synchronizing mechanism in which electro-magnets are used, the combination
with the light lever, trigger, or armature 43, of the spring 57, acted upon by pins
on the discs 25, or on the lever 37, or of equivalent means operated by the
independent action of the synchronizing mechanism; or by the operation of the
clock movement, for setting back the armature and avoiding the possibility of
derangement of the action of the apparatus by residuary magnetism, substantially
as hereinb fore described.
5. The combination with synchronizing mechanism, of the lever 41, 36, 37, or of
equivalent means operated by some part of the works or movement of the clock to
which the mechanism is applied, for locking the synchronizing mechanism, and for
unlocking it and preparing it for its synchronizing operation by the operation of
the clock, substantially as hereinbefore described.
31
6. In synchronizing mechanism in which the hand to be corrected or its equivalent
is acted upon and corrected by partially rotating arms actuated by the independent
operation of synchronizing clockwork, the arrangement of the trains of gearing,
and the combination of a spring or equivalent means therewith, in such a manner
as that upon the cessation of the synchronizing operation, the part of the train
directly operating the arms will be automatically disconnected and reversed by
the operation of the said spring causing the instant return of the arms to their
normal position, substantially as herein before described.
7. In synchronizing mechanism in which the hand to be corrected or its equivalent
is directly acted upon and corrected by partially rotating arms, the improved
method hereinbefore described of actuating such arms by the direct connection and
operation of synchronizing clockwork, substantially as herein before described.
8. In synchronizing mechanism consisting of or comprising an arrangement of
clockwork having its synchronizing action independently from the action of the
clock to which it is attached, or from the mechanism or means for receiving the
time signal; the combination of such means as are herein before described, or of
equivalent means, for keeping the synchronizing clockwork (until it has its
independent action) under the double control of the clock by which it is firstly
unlocked, and of the means for receiving the time signal by which it is finally
liberated, substantially as hereinbefore described.
9. The combination of a bell or gong or flashing signal with such synchronizing

page_text: mechanism as is hereinbefore described, to cause the same to audibly or visually
indicate the true time, substantially as hereinbefore described.
10. The means hereinbefore described for enabling the nett cumulative deviation
of a clock from true time during a given period for which it has been synchronized
to be registered and easily ascertained for the purpose hereinbefore mentioned,
such means consisting in the combination with the minute and seconds hands, of.
pointers or index fingers having a fixed position with relation to the arbors of the
minute hand or seconds hand, but not with relation to the minute hand or seconds
hand, substantially as hereinbefore described.
In Witness whereof, I, the said William Samuel Harrison have hereunto set my
hand and seal this 9th day of February in the year of our Lord One thousand
eight hundred and eighty four.
P
Witness. CHARLES AUBREY DAY. Fel. Inst. P.A.
Office for Patents.
W. S. HARRISON (L.S.).
321. High Holborn. London. W.C.