CERTAIN IMPROVEMENTS IN CHRONOMETERS
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GOTTLIEB ULRICH, late of Nicholas Lane, in the City of London, but now of
Red Lion Street, in the Parish of Saint Mary, Whitechapel, and County of
Middlesex, Chronometer. Maker, send greeting.
WHEREAS His late most Excellent Majesty King William the Fourth, by
His Royal Letters Patent, under the Great Seal of Great Britain, bearing
date at Westminster, the Twenty-second day of April, in the seventh year of
His reign, and in the year of our Lord One thousand eight hundred and
thirty-seven, did, for Himself, His heirs and successors, give and grant unto
me, the said John Gottlieb Ulrich, His especial license, full power, sole privilege
and authority, that I, the said John Gottlieb Ulrich, my executors, adminis-
trators, and assigns, or such others as I, the said John Gottlieb Ulrich, my
executors, administrators, or assigns, should at any time agree with, and no.
others, from time to time and at all times during the term of years therein
mentioned, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of
"CERTAIN IMPROVEMENTS IN CHRONOMETERS;" in which said Letters Patent is
contained a proviso, obliging me, the said John Gottlieb Ulrich, by an instru-
ment in writing, under my hand and seal, particularly to describe and ascertain
the nature of my said Invention, and in what manner the same is to be per-
formed, and to cause the same to be inrolled in His Majesty's High Court
of Chancery within six calendar months next and immediately after the date
of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said John
Gottlieb Ulrich, do hereby declare that the nature of my said Invention, and

page_text: the manner in which the same is to be performed, are particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
My improvements in chronometers apply to several constructions of instru-
ments for measuring time, and have for their object, first, a mode of ensuring
a continued action of the balance of a chronometer, by means of improved
escapements or mechanism, which prevent the liability of the works being
brought to rest by any sudden shock or circular motion of the instrument in
the plane of the balance, which are effected by means of novel constructions
of detents.
Second, self-acting regulators, or modes of compensating for the expansion
and contraction of the balance spring under variations of temperature, which
also afford the means of employing a material for the balance which will not
be subject to magnetic influence; and also a mode of adjusting the compen-
sating parts of the pendulum of an astronomical timekeeper.
Third, an improved mechanism for stopping the hands of a watch without
interrupting the action.
Fourth, a new mode of locking and unlocking the striking parts of such
chronometers as report the time.
Fifth, a mechanism for discharging the striking parts of an alarm or warning
watch.
And sixth, a mode of preventing the oxidation of the springs of chronometers,
by covering them with a thin coat of some metal which is not liable to become
oxidated.
These improvements are more particularly set out and exhibited in the
acccompanying Drawings, and will be made evident by the following explana-
tions and descriptions of the details of the several heads above mentioned
(that is to say) :-
Fig. 1 is a plan or horizontal representation of one of my improved escape-
ments, drawn upon a large scale; Fig. 2 is another representation of the same,
the parts being in different positions to those in Fig. 1; and Fig. 3 is an
elevation or edge view of the same. The escapement wheel is shewn at a, a, a,
having a series of elevated teeth 1, 2, 3, &c., which act upon the detent pallet;
the balance b, b, is fixed on the axle c, which axle also carries the impulse
pallet d, the discharging pallet e, and the circular guard f, f. The balance
spring g is attached to the pendulum collet at one end and to the stud at the
other, in the usual way. The spring detent h, h, fixed into the stud i carries
the ruby pallet k, which pallet, by coming in contact with the teeth 1, 2, 3, &c.

page_text: of the escape wheel, stops the rotation of the escape wheel between each
impulse. Another pallet l, intended as an auxilary to the spring detent, is
also attached thereto by means of a sinall bent arm m, which arm when the
detent escapes from the discharging pallet comes against the banking screw n
in the end of a piece o extending from the cock of the escape wheel. The
end of the detent has a right-angle arm p which carries the repassing spring q.
From the end of the detent there is also a crooked armr extending, which
carries a small guard pin at its extremity. This pin is designed, in the event of
any sudden jerk being given to the instrument, to come against the periphery.
of the circular guard f, and thereby prevent the detent pallet k from being
thrown out of the teeth of the escape wheel.
Having described the construction of one modification of my improved escape-
ment, I now proceed to explain the manner in which it operates. Fig. 1 shews
the positions of the parts of the escapement when in a state of rest, the point
of the tooth 5 of the escape wheel bearing against the detent pallet k. The
balance being now made to move round a very short distance backward (say
about four degrees) the discharging pallet e will pass the end of the repassing
spring q, and in so doing the balance spring 9 will be put into a slight degree
of tension. The balance will by these means be now disposed to return in
the opposite direction, and in so doing will strike against the end of the repass-
ing spring 9 and force the spring detent forward, which means the pallet k
and the escape wheel be
of the detent will be withdrawn from the tooth 5
allowed to move onward. By this returning movement of the balance the
impulse pallet d will be brought into the circular obit of the teeth of the
escape wheel, and the tooth 7 will now act against the impulse pallet d, and
as it passes through the angle of escapement (as shewn by dots) will impel
the balance onward and put the balance spring into a state of considerable
tension. The tooth 7 now escaping from the impulse pallet d, the tooth 6
will, by the movement of the escape wheel, be brought into the former.
situation of the tooth 5, bearing against the pallet k, and there remain until
the balance by returning repeats the same evolutions. In this way the subse-
quent tooth of the escape wheel come successively into operation upon the
pallets at equal intervals of time, and so regulate the movements of the-
chronometer. In the event of the detent not returning to its banking n in
sufficient time to catch the point of the tooth of the escape wheel, the internal
surface of the tooth would come in contact with the auxiliary pallet on the
spring detent, by which means the progress of the escape wheel would be
arrested, and the pallet, by gliding along the inclined surface at the back of
the tooth, would cause the detent to be drawn into the proper situation for the

page_text: pallet k to receive the end of the tooth as required. In order to prevent the
に
pallet upon the spring detent being thrown out of the teeth of the escape
wheel at any other time except when the impulse pallet d is acted upon, the
guard pin at the end of the bent arm r is so situated so as to come against
the periphery of the circular guard f, which consequently retains the detent
in its proper position. Fig. 4 is a separate view of these parts n the position
in which this guard pin might come into operation.
Fig. 5 represents a modification of the before-described escapement, in
which two spring detents are employed acting alternately upon the escape
wheel. The escape wheel a, a, a, has two sets of teeth; those on the face of
the wheel 1, 2, 3, &c., thirty in number, (being shaped as the upper part of a
gothic arch placed sideways,) act upon the impulse pallet; those on the under
surface 1, 2, 3, &c., fifteen in number, shewn by dots as oblique wedges,
placed at angles between the radius and the tangent, act upon the detent pallets.
The axle of the balance is shewn at b, on which are fixed two discharging
pallets c and d, two circular guards, as before described, and the impulse pallet f.
The spring detents g and h are fixed in studs, one on each side of the escape
wheel, tending towards the axis of the balance, and carrying each a detent
pallet i and . These spring detents are partially shewn above at Figures 6
and 7, removed from the instrument for the purpose of exhibiting them
more distinctly; the impulse pallet f being supposed to be moving in the
direction of the small arrow, the discharging pallet c will raise the detent g,
and lift the pallet i cut of the teeth of the escape wheel. At this moment,
the inner curved surface of the tooth 6 is beginning to act upon
the outer
curved surface of the impulse pallet f, pushing the pallet, and consequently
the balance, round in the direction of the small arrow, which brings the
balance spring into tension, and when the impulse pallet has passed away
from the tooth 6 the escape wheel a proceeds in its rotation until it is
arrested by the oblique tooth 3* coming in contact with the pallet k on the
detent h, the impulse pallet passing on through the space between the gothic-
shaped teeth 2 and 3, which will then be opposite to the course of the pallet f
From the state of tension which the balance spring has now acquired the
balance will be induced to return, carrying the impulse pallet in the direction
opposite to that of the small arrow, through the space between the teeth 2
and 8, and when it arrives at the space between the teeth 6 and 7 the dis-
charging pallet & will come in contact with the repassing spring of the detent h,
and lift the detent, so as to draw the pallet k away from the tooth 3*. The
escape wheel proceeding in its rotation, the outer curved surface of the tooth 7
will act against the inner surface of the impulse pallet f, and push it onward

page_text: in the direction opposite to the small arrow, and thus the balance spring being
again brought into a state of tension, the balance with the impulse pallet will
return in the direction of the small arrow and perform the evolutions as
described above. Fig. 8 represents a slight modification of the last-described
mechanism, in which the only difference is in the position of the impulse pallet.
Another modification of my improved escapement is shown at Fig. 9, in
which a pivot detent is employed for arresting the rotation of the escape wheel,
in place of the spring detents, above described in reference to Fig. 5. This
Fig. 9 represents the upper surface of the escape wheel a, a, a, having a series
of thirty gothic teeth as before upon its face, and a siniilar number of segment-
formed teeth placed sideways on its under surface, as shewn by dots, but which
under surface of the escape wheel is more perfectly seen at Fig. 10, and an
elevation or edge view of Fig. 9 is represented at Fig. 11. The detent b
screwed on to the discharging piece c is formed by two arms, each carrying a
ruby pallet d and e, which together move upon the axle f. The end of the
discharging piece c is formed as a fork, shewn more evidently in the separate
Figure 12, and this forked end of the discharging piece is acted upon by two
pins in the face of the disc g, fixed on the balance axis h; upon the balance
axis is also fixed the impulse pallet i, which is acted upon by the upper circle
of teeth on the face of the escape wheel, exactly in the same way as described
in reference to Fig. 5. These Figures represent the escapement in a state of
rest, both the pallets d and e of the detent at this moment standing free from
the circle of teeth 1, 2, 8*, &c. on the under surface of the escape wheel;
the escape wheel is therefore allowed to proceed in its rotary motion in the
direction of the arrow, and in so doing the outer surface of the tooth 3 will
act upon the inner surface of the impulse pallet i, forcing it and the balance
round (as in Fig. 5) in the direction of the arrow, as shewn in the partial
representation of the escapement at Fig. 13, and by so moving the balance
axle, one of the pins in the disc g acting upon the fork of the piece c, will
cause the pivot detent to bring the pallet d behind the segment tooth 3*, into
a situation ready to arrest the progress of the escape wheel, by stopping the
tooth 4 when it arrives. By these means the balance spring will be brought
into a state of tension, which will cause the balance, with the impulse pallet i
and disc g, to return in the direction opposite to the arrow in Fig. 13, and in
so moving, the pin in the disc g will come in contact with the forked end of
the piece c, and shift the pivot detent so as to withdraw the pallet d from the
tooth 4, and bring the pallet e behind that tooth ready to arrest the progress
of the escape wheel by stopping the tooth 5* when it arrives. Thus the action
of.the.escapement is effected at regular intervals of time. The banking pins

page_text: confine the extent of action of the pivot detent, but a small pin in the end of
the piece c, intended to fall into a notch in the periphery of the disc g, prevents
the detent from shifting its position, except at the moment when the two pins
in the disc enter the fork. Fig. 14 represents a slight variation from or
modification of the last-described escapement, in which two series of small
wedge-formed teeth are placed in inclined positions round the under surface of
the escape wheel, as shown by dots. In order to correspond with the positions
of the two circles of inclined teeth, the detent pallets d and e are fixed in
angular positions in the arms of the detent. Fig. 14 represents the escape-
ment in a state of rest; and Fig. 15, which gives but a partial view of the
escape wheel, represents the escapement in a state of motion.
Fig. 16 is another modification of the plan proposed in Fig. 5, in which the
detent pallets are differently situated, but all the other parts are the same as
before described.
It is scarcely necessary for me to say, in closing this description of my
improved escapements, that the parts or principles of construction and action
thus set out are susceptible of still more variations or modifications. My first
mode of compensating for the expansion and contraction of the balace spring
of a chronometer under variations of temperature is represented at Fig. 17 in
a plan or horizontal view, and at Figure 18 in an elevation or edge view.
In these Figures, a, a, is a brass plate to bo attached to the upper plate of
the instrument; b, b, are two long bars, called pendulum studs, each having a.
spring at its stationary end. To the reverse end of each of these studs the
outer extremity of one of the two balance springs c and d is attached, the
inner extremities of these springs being made fast to two collets on the balance
axle. A straight plate of platina e, e, is affixed by screws to an adjustable
sliding piece f, mounted on the plate a; upon the platina plate two brass tubes
g, g, are mounted, the outer ends of which are made fast to the plate, but the
inner ends of the tubes are attached to the long bar pendulum studs e, e.
When the tenperature of the atmosphere, by an increase of heat, causes the
tension of the balance spring to relax owing to the expansion of the metal, the
brass tubes g, g, by expanding also, cause the ends of the pendulum studs to
approach each other, thereby drawing the springs into tension, and of course,
when the heat becomes reduced, the brass tubes by contracting will draw the
pendulum studs farther apart, and thereby partially uncoils the balance springs.
Another mode of compensating for the expansion and contraction of the
balance spring under variations of temperature is shewn in Fig. 19.
a, a, is
the brass plate carrying the compensating apparatus; the balance spring is
shewn at b, one end of which is attached to a flexible arm or stud c, the other

page_text: end to the collet on the balance axle, as usual. A brass frame d, d, placed upon
an adjustable slide carries two steel or platina rods e, e, attached by joints, and
connected in the middle. From the junction of these rods a connecting rod f
passes up to a spring lever g, the acting end of which lever is attached to a
pair of lever arms h, h, which carry the axles of two rollers i, i; springs j, j,
act at the backs of these lever arms, for the purpose of pressing the peripheries
of the rollers i, i, together, or rather to cause them to take tight hold of the
flexible arm or stud c. In the event of the brass frame d, d, expanding, the
force of the spring lever g draws up the jointed rods e, e, and raises the arms
h, h, and rollers i, i, so as to cause the periphery of the rollers to pinch the
flexible arm or stud c higher up, by which means the tension of the spring b
becomes increased; when the frame d contracts by cold, the reverse operation
takes place, and the spring b becomes relaxed. A small piece of metal k is
fixed upon the brass plate, against the edge of which one of the rollers acts,
for the purpose of steadying them, and confining the position of the spring
arm c. The adaptation of these modes of compensating for the expansion and
contraction of the balance spring allow of the employment of such materials
for the balance as are not subject to magnetic influence, (viz.,) platina,
palliadium, glass, &c.
Fig. 20 represents part of a compensation pendulum of an astronomical
timekeeper, the pendulum being shewn in section.
a is a small escape
wheel with teeth, as in Fig. 14, intended to be actuated by clockwork behind.
At the lower end of the pendulum (which is to vibrate only about the
distance of an eighth of an inch) a small impulse pallet bis fixed, and a
forked pivot detent c with a pin and pallet are adapted, as shewn in Fig. 14
and 15, described above, which contrivance is designed to keep up the
vibratory action of the pendulum. The mode of adjusting the compensation
of this pendulum is by means of a double screw d, d, formed on the internal
and external surfaces at the end of the nut e, e, which passes into the com-
pensation tubes, and on the outside of the compensation tube a clip with a
thumb-screw fis applied for the purpose of binding the tube tight upon the
nut d.
My improved mechanism for stopping the hands of a watch without inter-
rupting the going of the works is shewn at Fig. 21. a is the seconds wheels,
turning loosely upon its axle; b is a coiled spring, attached to an arm c, fixed
on the seconds wheel axle; the other end of this spring is attached to a
stud extending from the inner part of the seconds wheel. d is a spring arm,
having a tooth at its end, which is occasionally allowed to fall into the
teeth in the seconds wheel, for the purpose of stopping its rotation. When

page_text: this stoppage of the seconds wheel takes place, the seconds hand, which
is upon the collar or shoulder of the wheel, stops also, but the axle
continues. revolving, winding the spring 6 up to tension, and when the
axle has revolved for the space of one minute; the tail of the arm c, coming
in contact with an inclined plane at the end of a spring lever e, causes
that lever to rise, and to lift the tooth of the arm d out of the ratchet teeth
of the seconds wheel and release it. The tension of the spring b now
causes the seconds wheel,to fly round and to recover its proper position, which
is determined by the point of the arm c stopping against the stud f. The
minute wheel g, situate in the centre of the plate, is mounted in a similar way
to the seconds wheel, having a coiled spring and a detaining arm h with a tooth
at its end taking into the ratchet teeth of the minute wheel. The mechanism
by which these wheels are stopped, for the purpose of holding the seconds and
minute hand, is connected with the pendant i, fixed in the socket j. A sliding
piece within the pendant acts upon a long curved lever k, l, which has its
fulcrum pin fixed in the plate at m, and a bent tail piece n extending from
this lever acts upon the longer arm o of a double lever o, t, fixed upon a disc p.
To this disc p is attached the arm d, with the tooth taking into the seconds
wheel, and to the same disc is also attached an arm q with an adjusting screw r
which forms the banking for the spring lever e. A strong spring s presses
against the tail t of the double lever, for the purpose of raising the longer arm
o of that lever, and keeping the tooth of the arm d out of the seconds wheel.
When it is required to stop the hands of the watch, the pin in the pendant is
to be pressed inward, which will act upon the lever k, l, and cause the bent
tail piece n to depress the arms and also the arm d, thereby throwing the
tooth of the arm & into the ratchet teeth of the seconds wheel for the purpose
At the same time the arm of the
of stopping its rotation, as before said.
long bent lever will be made to act upon the tail piece of the arm h, and cause
the tooth of that arm to be thrown into the ratchet teeth of the minute wheel
and stop its rotation; as long, therefore, as the pin in the pendant is pressed
inwards, the seconds and minute wheels will remain locked, excepting during
the escapement of the seconds wheel every minute, as described above, but
the moment the pressure is taken off the push pin, the force of the springs s, v,
and u will throw all the levers back out of action. When the retaining force
is thrown upon the seconds and minute wheels, as described, it will be neces
sary to put in action a spring that shall be equivalent to the retaining force.
This is done by means of a double-action spring lever w, which is thrown into
tension by the depression of the arm k, causing the catch to take into the
teeth of the fusee wheel y.
19

page_text: The mechanism for locking and unlocking the striking parts of such chro-
nometers as report the time is shewn at Fig. 22. The wheel which carries the
minute band is shown at a, taking into a corresponding wheel b, into which is
inserted a pin c, intended as it revolves to raise the lever d. To this lever is
attached the double-armed lever e, f, both turning freely upon a stud g fixed
in the plate. A detent lever hangs upon a stud at i, the extremity of which
lever bears upon the end of the arm e, and a tooth at the under part of this
lever takes into a curved rack k, forming part of a lever 1, which turns upon a
stud m fixed in the plate. A fly n fixed upon the last pinion of the striking
work is stopped by the end of one arm of a double lever o, p, which lever
turns upon a fixed stud q. The other arm p of this lever has a tooth taking
into a notch in a disc r upon the arbour of the tumbler wheel. A pin in the
arm p rests against the end of the longer arm of a lever s, which is held up
by its tail bearing upon the end of the curved rack k, and this curved rack
with its lever is confined in the position shewn in the Figure by the tooth
under the lever h standing before the last tooth in the rack. As the wheel b
revolves, the pin c is made to raise the lever d every hour as it passes, and in
so doing causes the lever d to lift the lever h and release the rack k from the
detaining tooth; the rack k is then carried forward in the direction of the
arrow, by the force of the spring't acting upon the tail piece of the lever 7,
which raises the shorter arm of the lever 1, and throws a pin near its end
against the periphery of the snail v, fixed upon the star wheel u. The receding
of the rack now allows the shorter arm of the lever & to be pressed down by
its spring w, and the longer arm of the levers to raise the arm p of the double
lever p, o, and lift its tooth out of the notch of the disc r, at the same time the
other arm o of this lever being raised, allows the fly n to revolve. The fly n
thus permitted to pass round in the direction of the arrow, giving warning, until
a pin near its end catches against the hook at the end of the now elevated
arm f of the double lever e, f, which arrests its progress until the pin c in the
minute wheel 6 has escaped from the tail of the arm d, when the levers d, e, f,
and h are allowed to fall into their proper positions. The fly being now at
at liberty revolves freely, and allows the disc r with the tumbler or gathering
pallet y to revolve also, by means of the well-known train of wheels, not shewn
in the Figures. The gathering pallet y as it goes round takes successively
into the teeth of the rack k, and thereby forces the rack back into its former
position, when the tail of the lever s again descends on to the end of the rack,
and the levers p and o fall, the one bringing its tooth into the notch of the
disc r, the other stopping the rotation of the fly.
The mechanism for discharging the striking parts of an alarm watch is

page_text: shewn at Figures 23 and 24. a is a disc, placed upon the axle of the minute
pinion; b, a similar disc upon the socket of the hour wheel. These discs are
not absolutely fixed, but fit tightly. c, d, is a double-armed lever, upon a
fulcrum e, acted upon by a spring f. At the outer end of the lever c there is
a catch, intended to arrest the rotary action of the fly g.
Fig. 23 exhibits the improved mechanism when the alarm is in a quies-
cent state, but as the ordinary works of the watch go on, the discs a and b
come round into such positions as will allow the teeth on the levers c and d to
fall into the notches of the disc a and b, as seen in Fig. 24, which liberates
the fly, and allows the alarm to go off. The alarm is set by turning the
dises round until an index upon each comes opposite to the hour or minuto
marked on the dial plate at which the alarm is required to be discharged.
My mode of preventing the oxidation of the metal composing the springs
of chronometers, by covering them with a thin coat of some metal which is
not liable to oxidation, is effected by dipping the metal, after its form is finished
and its surface polished, into an etherial solution of gold, platina, or paladium,
then instantly withdrawing it from the solution and plunging it immediately
into cold water, which will cause a deposit of the metal in the solution to
remain on the surface of the articles so treated, and leave it perfectly plated,
and defended from the action of the atmosphere.
In witness whereof, I, the said John Gottlieb Ulrich, have hereunto set
my hand and seal, this Twenty-first day of October, One thousand
eight hundred and thirty-seven.