CERTAIN IMPROVEMENTS OF CHRONOMETERS
Year: 1825

page_text: ULRICH'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GOTTLIEB ULRICH, late of Bucklersbury, Cheapside, in the City of London, but
now of Upper Rosomons Street, in the Parish of St. James, Clerkenwell, in
the County of Middlesex, Chronometer Maker, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of that part of the United Kingdom
of Great Britain and Ireland called England, bearing date at Westminster, the
Twenty-sixth day of March last past, in the year of our Lord One thousand
eight hundred and twenty-five, and the sixth year of His reign, give and grant
unto me, the said John Gottlieb Ulrich, my executors, administrators, and
assigns, His especial licence, full power, sole privilege and authority, that I,
the said John Gottlieb Ulrich, my executors, administrators, or assigns, 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 OF CHRONOMETERS;" in which
said Letters Patent there is contained a proviso, that if I, the said John
Gottlieb Ulrich, shall not particularly describe and ascertain the nature of my
said Invention, and in what manner the same is to be performed, by an instru-
ment in writing under my hand and seal, and cause the same to be inrolled in
His Majesty's High Court of Chancery within two calendar months next and
immediately after the date of the said Letters Patent, that then the said.
Letters Patent, and all liberties and advantages whatsoever thereby granted,

page_text: shall utterly cease, determine, and become void, as in and by the same,
relation being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in complianco with the said proviso, I, the said
John Gottlieb Ulrich, do hereby declare that the nature of my said Invention,
and 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 Drawing annexed, that is to say :-
My improvements on chronometers will be best understood by refering to
the present construction of chronometers, and pointing out what I consider to
be their defects. Upon the present principles of construction, the impelling
power (viz.), the mainspring communicates its impulse to the balance through
a long train of wheels and pinions, whereby innumerable inaccuracies are
liable to arise from the imperfect shape of the teeth, from the varying fluidity
of the oil applied to the pivots, and from the unequal force of the mainspring
itself in the different parts of its tension. These irregularities are increased by
the multiplied velocity at the end of the train, so that the impulse given to the
balance will not be uniform, its motion being impeded by the force it is made
to exert in unlocking the train detent. To remedy these objections, I have so
constructed the escapement of my improved chronometer that the power of
the mainspring shall not immediately give impulse to the balance through the
train, but shall raise an independent remontoir spring lever, for the purpose of
striking a detached balance, and causing it to vibrate independently of the train.
I thus get rid of the irregularities, whatever they may be, of the train which
would interfere with the regular going of the chronometer, the return of the
balance releasesing the independent spring lever, which, after giving a new
impulse to the balance, proceeds by a blow to unlock the train at regular inter-
vals and effect the successive escapements.
In the Drawing bereunto annexed, Fig. 1 represents the several parts of the
improvement upon an enlarged scale (the escapement being in a state of rest).
The chronometer is constructed with a train of wheels, as usual, up to the escape
wheel a, which is moved by a pinion upon its axle; b is the train detent (shewn
detached in Fig. 2), having a ruby pallet c at its extremity, which stops the
rotation of the wheel a by locking against its teeth; d is the independent spring
lever or remontoir, for giving impulse to the balance. This is locked in a state
of tension by a ruby catch pallet e, at the end of the impulse detent f. When
the balance g (which is shewn in a vertical possession in Fig. 3) has been put
in a state of vibration, and is moving in a retrograde direction, the pallet h
upon its axle, is enabled to pass the end of the impulse lever d freely, and the
small pallet i, also upon the axle of the balance lower down, escapes past the

page_text: spring at the back of the impulse detent; but when the balance returns,
the small pallet i, coming in contact with the end of the spring k, causes the
impulse detent to be moved sufficiently far to enable the catch pallet e to
slip from its hold through a notch z, at the end of the lever d, shewn in the
vertical view, Fig. 4. The spring of the remontoir lever d now exerting its
force, throws the lever forward and causes its end to strike against the pallet h
upon 'the axle of the balance, giving it a new impulse; but it has a further
important office to perform (viz.), unlocking the train, for when the lever d
has reached the situation shown by dots, it quits the pallet and proceeds for-
ward, by which means an inclined plane y, near the end of the impulse spring
(see Fig. 4), strikes against the pallet c at the end of the train detent (shewn
separately at Fig. 5), and pushes the pallet from the tooth, permitting the
escape wheel to run. The tooth 7 of the escape wheel now pressing against
the pallet of the semicircular plate m, causes the plate to turn upon its pivots,
and bring the lifting arm n (see the detached Fig. 6) into the position shewn
by dots in Fig. 1, and with it the spring lever, which by that. means is again
locked by the pallet c. Immediately after this the tooth 9 comes against the
pallet o, and returns the semicircular plate and the lifting arm n into the
position shewn in the Drawing, Fig. 1, which brings the spring of the remon-
toir lever into a state of tension ready to give the next impulse. The tooth 15
by this time having arrived at the pallet c, the escape wheel is stopped. The
pallet i now striking again upon the end of the spring k, as before, causes
anothor tooth of the wheel a to escape, and so on; thus the regulation of the
train is effected. In order to prevent the escape wheel and the spring lever
from tripping, I have introduced two precautionary contrivances, the first of
which is a guard spring p, attached by a screw to the plate at 9, from which
spring a bent arm r extends, and when the end of the spring escapes from the
tooth of the wheel a, the bent arm comes against the side of the impulse
detent f, and prevents it from vibrating. The second contrivance is adapted
to confine the train detent and compel its pallet to lock against the tooth of
the wheel a, for which purpose a swelling piece is attached to the side of the
train detent, which so nearly fills the notch y, Fig. 4, in the spring lever that
the detent is prevented from moving.
These said precautionary contrivances form most essential parts of m
Invention, and which are hereby particularly claimed by me. As, however,
there are several parts exhibited in the Drawings which are not new, and
others that are new, which will admit of being modified and adapted in
several ways besides those shewn, I wish it to be understood that my claim
of Invention and Patent right consists,―

page_text: First, in a mode of performing the two operations of returning the spring
lever to its dent and of giving tension to its spring by the two opposite motions
of the alternating pallets.
Secondly, in unlocking the train by a force independent of the balance.
Thirdly, in the mode of preventing the train detent from jumping out of the
teeth of the escape wheel at the time the tooth comes in contact with it, and
also of preventing the escape of the impulse spring from its detent at the
period of locking, which two last-mentioned objects are of particular import-
ance to all remontoir escapements, as the accidental escape of several teeth,
commonly called tripping, is hereby effectually prevented without interfering
with the action of any of the mensurating parts of the mechanism.
In witness whereof, I, the said John Gottlieb Ulrich, have hereunto set
my hand and seal, this Twenty-sixth day of May, in the year of our
Lord One thaneand night hundead and smante fin
JOHN GOTTLIEB (L.B.) ULRICH.
AND BE IT REMEMBERED, that on the Twenty-sixth day of May, in the
year of our Lord 1825, the aforesaid John Gottlieb Ulrich came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according to
the tenor of the Statute made for that purpose.
Inrolled the Twenty-sixth day of May, in the year of our Lord One
thousand eight hundred and twenty-five.