IMPROVEMENTS IN CHRONOMETERS
Year: 1828

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
GOTTLIEB ULRICH, of Cornhill, in the City of London, Chronometer. Maker,
send greeting.
WHEREAS His most Excellent Majesty King George the Fourth, by
Ilis 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 Nineteenth day of April, in the ninth year of His reign, did give and
grant unto me, the said John Gottlieb Ulrich, my exors, adñors, and assigns,
His especial licence, full power, sole privilege and authority, that I, the said
John Gottlieb Ulrich, my exors, admors, and assigns, or any of them, during
the term of years therein expressed, might make, use, exercise, and vend,
within that part of the United Kingdom of Great Britain and Ireland called
England and Wales, and the Town of Berwick-upon-Tweed, my Invention
of "IMPROVEMENTS IN CHRONOMETERS;" in which said Letters Patent there 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 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 the nature of my said Invention, and

page_text: the manner in which the same is to be performed, by the following description
thereof, reference being had to the Drawings hereto annexed (that is to say) :—
My present improvements in chronometers are designed, in the first place,
to reduce the labour of the balance; secondly, to govern the action of the
escape wheel; thirdly, to lock the train detant; fourthly, to discharge the train
detant; and fifthly, to construct a compensating balance upon a superior plan
to those which have been heretofore made; which improvements are to be
considered as variations of the principles set forth in the Specification of my
former Patent, dated 25 March 1825, for an improved remontier detached
escapement (to which Specon I refer), and also additions to the same. The mode
by which I reduce the labour of the balance is by diminishing the strength of
the impulse detant, and applying an auxiliary spring lever for the purpose of
giving stability to the detant at the time that the impulse spring lever is locking.
The action of the escape wheel is governed by a bar or balance attached to the
axis of the alternating pallets. This bar carries two adjustable weights near
its extremities, which being placed nearer to or further from the centre,
causes it to oscillate faster or slower. To lock the train detant a spring guard
is attached to the escapement plate which is kept by the impulse spring
lever when locked behind it, and by that means the train detant is prevented
from being thrown out of the teeth of the escape wheel, but when the impulse
spring lever is unlocked, the said spring guard is released, and the train detant
set at liberty. To discharge the train detant a bent lever is attached to the
alternating pallet piece, at one end of which lever a pin is fixed, and the impulse
spring lever striking against the pin causes an arm extending from the lever to
remove the train detant from the teeth of the escape wheel. Before describing
the novel construction of my improved compensation balance, I shall explain
the details appertaining to the four first heads of my Invention, as above stated,
and exhibit the forms, positions, and actions of the several parts.
b
Fig. 1 of the accompanying Drawings shew the escapement in a quiescent
state, drawn upon a scale of about three times larger than the real instrument;
a is the balance axle, which being moved round in the direction of the arrow,
the small discharging pallet 6 upon that axle will be enabled to escape freely
past the spring c without disturbing any of the mechanism, but on the return
of the balance (that is, its movement the reverse way to that of the arrow),
the pallet b comes in contact with the end of the spring c, which is in that
direction stopped against a small projecting arm extending from the impulse
detant d; consequently the impetus of the balance causes the pallet 6 to carry
the impulse detant d back with it, and by that means to withdraw the pallet l
at the end of the impulse detant from the point of the impulse spring lever f

page_text: which positions of these parts are shewn in Fig. 2.
The impulse pallet g
affixed to the axle of the balance is at this moment in a situation to receive
impulse, and the impulse spring lever f being now at liberty its elevated
part comes in contact with the impulse pallet g, as seen in Fig. 3, and
drives it and the balance round. The train detant guard h, which in Figs. 1
and 2 is seen standing nearly at right angles to the train detant i, and
thereby locking it, is by the advance of the impulse spring lever f allowed
to fall against the banking pin j, and by that means to unlock the train
detant, as seen in Fig. 3. The impulse spring lever f, continuing its action
on the pallet g, pushes it and the balance forward as in seen in Fig. 4, and
then escapes from it as in Fig. 5, when by the impulse spring lever f striking
against a pin a set in the end of the bent lever k, that lever is moved from the
situation shewn in Fig. 4 to that shewn in Fig. 5. An arm fixed at the back
of the bent lever k, called the discharging arm, is by the last-mentioned move-
ment of the bent lever pressed against a pallet m on an arm extending from
the train detant, which is by that means made to recede, and the pallet y on
the train detant is drawn from the tooth 1 of the escape wheel n, as shewn in
Fig. 5, thereby setting the escape wheel at liberty, which instantly moves
forward in the direction of the arrow, allowing the point of the auxiliary spring
lever o to drop behind the tooth, and the pin p at the extremity of its arm to
come against the back of the impulse detant 1, and thereby to hold it firmly ;
the tooth 7 of the escape wheel n now pressing against the face of the alter-
nating pallet g, as seen in Fig. 6, forces the pallet piece into the position
shewn in Fig. 7, carrying its adjusting bar 1, 7, into the oblique situation there
seen, which movement has caused the arms affixed to the pallet piece to carry
back the impulse spring lever into the position shewn in Fig. 1, its point being
now again held by the pallet at the end of the impulse detant. On the
tooth 7 quitting the face of the the alternating pallet q, as in Fig. 7, the tooth
9 comes in contact with the force of the other alternating pallet t, as seen in
Fig. 8, the force of which brings back the pallet piece, with the adjusting bar
and the arm s, to a state of rest in the situation shewn in the 1st Fig., which
places the impulse spring lever now held by the pallet 7 in a state of tension
ready to give the succeeding impulse to the balance in the manner. before
described. The further progress of the escape wheel causes the teeth 15 to
raise the point of the auxiliary spring lever o, and thereby to remove the pin p
from the holding the impulse detant. The tooth 15 now coming against the
pallet y at the end of the train detant, the escape wheel is stopped, and in
order to lock it and prevent tripping by any tremulous motion in the train
detant, the guard h, which has been brought back to its first situation by the

page_text: impulse spring lever, stands immediately behind the train detant and confines
it. There are two banking pins v, v, placed so as to receive the recoiling
stroke of the adjusting bar and bring it to rest... The ordinary construction of
balances applied to chronometers made of brass and steel are liable to much
interruption and irregularity of action from magnetic influence, and from the
effects of the two metals to separate from each other by their unequal expan
sions and contractions at every variation of temperature. My improved
balance is free, the former of these inconveniences not having a particle of
iron or steel about it, and is so constructed that the variable expansions and
contractions of its parts effect the compensation required. Fig. 9 is a hori
zontal representation of the balance drawn upon a scale of about twice that of
the real instrument. a, a, is a bar of platina, to which are attached by screws
the end pieces b and c. To the end piece 6 one extremity of the lateral brass
tube d is affixed, and to the other end piece c the extremity of a similar lateral
brass tube e is also affixed; from end pieces b and c the stems f. f, rise as
shewn, and to these stems f, f, are respectively connected the segments or
arms 9, 9, carrying the weights h, h, of the balance. When an increase of
temperature causes the metal of which the balance is constructed to expand,.
that expansion will be greater in the lateral brass tubes d and e than in the
platina bar a, the effects of which will be to bring the extremities of the
segments nearer toward the centre of oscillation, and consequently to increase
the velocity of the balance, tho' the parts are expanded, which expansion
would otherwise retard its velocity. The segments or arms g, g, must be con-
sidered as levers, the fulcrums of which are at f,f, and these, as well as the
extremities of the tubes d and e affixed to the end pieces b and c, may be
considered as comparatively stationary. It will now be perceived that as the
materials of which the balance is constituted expands,, the lateral brass: tubes d
and 6 elongate more than the platina bar a, and consequently the ends of
these tubes pressing against the tails of the levers or segments at i, t, the
opposite extremities of the levers or segments will be forced inwards, as shewn
by the dotted lines, the diameters of the balance thereby becoming smaller,
tho the parts have been actually expanded. It may be necessary. hero to
remark that the two end pieces b and c, and the two: segments. g, g, with the
stems f,f, and i, i, are all to be cut out of one solid piece of metal.
In witness whereof, I, the said John Gottlieb Ulrich, have hereunto set
my hand and seal, this Twenty-fourth day of July, in the year of our
Lord One thousand eight hundred' and twenty-eight.
JOHN GOTTLIEB (L.8.) ULRICH.

page_text: AND BE IT REMEMBERED, that on the Twenty-fourth day of July, in the
ninth year of the reign of His Majesty King George the Fourth, the said
John Gottlieb Ulrich came before our said Lord the King in His Chancery,
and acknowleged the instrument aforesaid, and all and every thing therein con-
tained and specified, in form above written. And also the instrument aforesaid
was stamped according to the tenor of the Statute made in the fifty-fifth year
of the reign of His late Majesty King George the Third.
Inrolled the Eighteenth day of October, One thousand eight hundred
and twenty-eight.