CERTAIN IMPROVEMENTS IN WATCHES AND OTHER TIME-KEEPERS
Year: 1856

page_text: LETTERS PATENT to Alexandre Tolhausen, of No. 7, Duke Street, Adelphi,
London, County of Middlesex, Sworn Interpreter at the Imperial Court
of Paris, for the Invention of "CERTAIN IMPROVEMENTS IN WATCHES AND
OTHER TIME-KEEPERS," a communication from Jacob Muma, of Hanover,
United States.
Sealed the 5th September 1856, and dated the 27th March 1856.
PROVISIONAL SPECIFICATION left by the said Alexandre Tolhausen
at the Office of the Commissioners of Patents, with his Petition, on
the 27th March 1856.
I, ALEXANDRE TOLHAUSEN, of No. 7, Duke St., Adelphi, London, County
of Middlesex, Sworn Interpreter at the Imperial Court of Paris, do hereby
declare the nature of the said Invention for "CERTAIN IMPROVEMENTS IN WATCHES
AND OTHER TIME-KEEPERS," being a communication from Jacob Muma, of Hanover,
United States, to be as follows:-
These improvements consist,-1st. In an escapement of novel character,
which is not influenced by shaking the watch, and is therefore more regular in
its action than any of the existing or known forms of escapement. 2nd. In a
novel device for compensating for the tendency to variation of the balance
consequent upon changes of temperature. 3rd. In certain novel arrangements
of the barrel, main spring, fusee, and chain, for the purpose of reducing the
friction on the fusee pivots and equalizing the friction on the barrel.

page_text: The first of these is composed of an escape wheel, to which two balances are
applied. To the staff of each of these balances is applied a segment of a
cylinder concentric to its respective balance; each balance receives in its turn
an impulse from the escape wheel working across the chord of its cylindrical
segment, and gives motion to its fellow by means of very fine teeth cut in their
periphery.
The second improvement consists in a stout ring of brass surrounded by a
closely fitting coil of spring steel, one end, of which is secured to the ring, the
other receiving the hair spring. The expansion and contraction of the brass
ring, caused by changes of temperature, being greater than that of the steel,
makes it move in a circumferential direction, and thus to diminish or increase
the effective lengths of the hair spring.
The other differences of arrangement between this watch and that heretofore
adopted are, 1st. The position of the chain relatively to the barrel and fusee,
so that the drag of the chain is on the side of the fusee from which the power
is transmitted. 2nd. The arrangement of the fusee in a manner the reverse of
that now used, so that when the watch is. wound up, and consequently the
spring at its greatest power, the chain drags equally on the two pivots of the
fusee instead of dragging nearly all on one point.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexandre Tolhausen in the Great Seal Patent Office on the
9th September 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDRE
TOLHAUSEN, of No. 7, Duke Street, Adelphi, London, County of. Middlesex,
Sworn Interpreter at the Imperial Court of Paris,, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria; by: Her- Letters
Patent, bearing date the Twenty-seventh day of March, in the year-of our
Lord One thousand eight hundred and fifty-six, in the nineteenth year. of
Her reign, did, for Herself, Her heirs and successors,-give and grant.
me, the said Alexandre Tólhausen, Her special licence that I the said
Alexandre Tolhausen, my executors, administrators, and assigns, or such
others as I, the isaid Alexandre Tolhausen, my-executors, administrators;
and assigns, should:iat any time agree-with, and no others, from time to
time and at all times thereafter during the term therein expressed, should
and lawfully might make, use; exercise, and vend, within the United Kingdom
"

page_text: of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
"Invention for "CERTAIN IMPROVEMENTS IN WATCHES AND OTHER TIME-KEEPERS," a
communication from Jacob Muma, of Hanover, United States, upon the con-
dition (amongst others) that I, the said Alexandre Tolhausen, my executors
or administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature of
the said Invention, and in what manner the sanie was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexandre Tolhausen, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement:-
The first of these improvements cousists in an escapement of novel character,
which is uninfluenced by shaking the watch, and is therefore more regular in
its action than any of the existing or known forms of escapement. A second
improvement consists in a novel device for compensating for the tendency
to variation of the balance consequent upon changes of temperature. And a
'third improvement consists in certain novel arrangements of the barrel, fusee,
main spring, and chain, for the purpose of reducing the friction on the fusee
pivots and equalizing the friction on the barrel.
The Invention is illustrated in the accompanying Drawing, in which Fig. I
is a plan of a watch movement with my improvements; Fig. 2 is a plan of the
same, having some parts removed to shew the arrangement of the main spring
and chain and the construction of the escapement; Fig. 3 isla side view of the
escapement and compensating device; Figs. 4 to 8, inclusive, are Diagrams
illustrating the action of the escapement; Fig. 9 exhibits a modification of the
escapement wheel; Fig. 10 is a side view of the barrel. and fusee; and Fig. 11
is a plan of the hair spring and compensating device. Similar letters of
reference indicate corresponding parts in the several Figs.
.
The escapement being the most important feature of the Invention.will be
first described. The escape wheel A may have its teeth a, a, either of the form
shown in Figs. 1 and 2, or that shown in Fig. 9, and may be made either. of
metal, or of ruby or other jewel. If made of metal, I make them of the form
shown in the former Fig.; but if made of jewel, I make them of the form shown
in the latter Fig. In the former case they have their two sides c, c, parallel to
a radial line passing through the centre of the tooth, and in the latter case
their sides form portions of circles e, e, described from equidistant points in a
circle d, circumscribing the inner edges of the faces of the teeth. In either

page_text: case their faces are slightly beveled inwards in the direction of their revolution,
which is indicated by arrows f, f. Two balances B, B, each having a hair
spring j, see Fig. 3, applied in the usual manner, are employed, one on each
side of the escape wheel, their axes being arranged in the same plane as the axis
of the escape wheel, and exactly in the circle d, described by the least prominent
edge of the faces i, i, of the escape wheel teeth, the said balances being geared
together to oscillate in opposite directions by very fine teeth, which are to be
cut and finished in the most accurate and smooth manner known, so as to work
together with the least possible degree of friction and without lubrication. Ou
the staff g of each balance is a cylinder, or, more properly speaking, a segment
of a cylinder h, or h", which is concentric to its respective balance, the versed
sine of the said segment being about equal to one-third of the diameter of the
cylinder, of which it forms a portion. Each balance receives in its turn an
impulse from the escape wheel by a tooth of the escape wheel working across
the chord of its cylindrical segment h, or he, and gives motion by the gearing
to its fellow in an opposite direction, and the escape wheel remains for a time
stationary between the operations on the segments in consequence of one of its
teeth resting on the cylindrical portion or are of one or other of the segments,
thus producing a perfect dead beat. The balances in their vibrations are
intended to make about one complete revolution. The escapement wheel
remains stationary during half a revolution of the balances.
The operation of the escapement is illustrated by the Figs. 2, 4, 5, 6, 7,
and 8, the Figs. from 4 to 8, inclusive, representing the cylindrical segment of
oue balance and one tooth of the escape wheel. In Fig. 2, a tooth a' of the
escapement wheel is giving impulse to the segment h of the right-hand balance
in the direction of the arrow, marked near it, and is just about escaping, having
worked nearly all across the chord of the said segment, and a tooth a" on the
opposite side of the wheel is just about to fall on the arc of the segment of the
left-hand balance, which is at the time rotating in the opposite direction to the
other seginent. It may be here observed that the escape wheel has an odd
number of teeth, so that every tooth has a space diametrically opposite to it.
To return to the operation: Fig. 4 represents the tooth a" at the time of the
escape of a having just taken place, the said tooth a" being just arrested by
falling against the arc of the segment * of the left-hand balance, which
continues rotating in the direction of the arrow, shown near it, till it has reached
the position in which it is shown in Fig. 5, by which time the force of the
impulse will have been counteracted by the action of the hair springs, which,
being coiled in opposite directions, react simultaneously upon the balances and
change the direction of the revolution of the segments, making the direction

page_text: of the revolution of h, as shown by the arrow in Fig. 6, which represents the
said segment as having gone back to the position in which it begins to receive
an impulse from the tooth a", which now presses against the inner edge of the
segment. The impulse continues as the segment turns, as is illustrated in
Figs. 6, 7, and 8, in the latter of which Figs. the tooth a" is represented about
to escape; and when this escape takes place, the segment h of the right-hand
balance will be in a condition to receive the tooth behind a', which operates
upon it in the same manner as a" has operated upon *. This alternate action
on the cylindrical segments of the two balances produces an exceedingly regular
escapement, which is not influenced by any shaking or jarring of the watch,.
for the balances being differently influenced by any movement of the watch,
the influence upon one will counteract that upon the other, and they will
vibrate their proper distance and neither more nor less, even though the watch
be violently shaken in a circular direction. This escapement requires less
impulse than a single balance escapement, owing to the peculiarly effective action
of teeth of the escapement wheel on the cylinders or cylindrical segments.
The device for compensating for the variations of the balance is applied to
each balance; it consists of a stout ring C, of brass, surrounded by a closely
fitting coil D of spring steel, as shown in Fig. 3, one end of the said coil being
secured to the ring, and the other end m being forked to receive and form a
curb to the hair spring ). The brass ring fits tightly to a fixed pivot p, which
is shown in Figs. 3 and 11, and is indicated by a dotted circle in Fig. 1. This
pivot is concentric to the staff of the balance, which passes freely through it.
The expansion and contraction of the brass ring by changes of temperature
being greater than that of the surrounding steel coil, causes the forked end of
the coil to move in a circumferential direction, and thereby to increase or
diminish the effective length of the hair spring, and thus to diminish or increase
its power, the expansion causing the effective length of the spring to be
diminished and its power increased, and the contraction causing its effective
length to be increased and its power diminished. The coils D, D, may have
one, two, or more turns round the ring C as may be requisite. The regulation
of the watch is effected by turning an endless screw q, which is fitted in suitable
bearings to gear with a toothed segment r, attached firmly to each ring C, so
as to turn both rings at once in opposite directions, and with them the coils D, D,
thus moving the forks or curbs m, m, on the springs to lengthen or shorten the
effective length of both, as may be necessary.
The arrangements of the barrel H, main spring E, fusee F, and chain G, in
my watch, differs from the arrangement of the corresponding parts of other
watches in two particulars. In the first place, the chain instead of being

page_text: arranged to draw on the opposite side of the fusee to that from whence the
power is transmitted Dy the,fusce wheel,s to the centre pinion t, as is illustrated
by the small diagram X, which exhibits a plan of the arrangement in other
watches, is arranged to draw on the same side as that from which the power is
given, as is illustrated in Fig. 1. In the old arrangement, shown in diagram X,
the drag of the chain is in the direction of the arrow 12, and the resistance
offered by the pinion is nearly in the direction of the arrow 13, both directions
being similar on opposite sides of, the centre of the. fusce, and the whole of
both these forces is thrown on the fusee pivots, thus producing the greatest
possible amount of friction; but in my arrangement, which is shown best in
Fig. 2, the drag of the chain, which is in the direction of the arrow 14, and
the resistance offered by the pinion, which is nearly in the direction of the
arrow 15, are in opposite directions on the same. side of the centre of the fusee,
and hence are made as nearly as possible to counteract each other in their
effect on the pivots of the fusee, and thus, the friction on the fusce pivots may be
reduced so as to average only about one-fifth of what it is in the old arrange-
ment. This new arrangement involves the arrangement. of the coil of the
main spring in a direction the reverse of what it is in the old arrangement of
the chain, and the consequent revolution of the barrel in the reverse direction.
The other point of difference in my arrangement of the barrel, main spring;
chain, and fusee, consists in reversing the positions of the larger and smaller
ends of the fusee, that is to say, placing the smaller end of the fusee next the
fusee wheels instead of the large end.. The effect of this is to bring the drag of
the chain at the time when the watch is fully wound, at which time the spring is
most powerful, opposite the middle of the length of the arbor v of the fusee,
as is illustrated in Fig. 9, which exhibits the chain fully, wound up, instead of
at one end of each, as is shown, in the diagram Y, which exhibits the old
arrangement fully wound, thus causing the friction to be equally distributed on
both ends of the barrel, and both pivots u, u, of the fusee arbor v, instead of
nearly all on one end of the barrel and one pivot of the fusee arbor. By the
above arrangements for reducing the friction on the fusee pivots, and equalizing
the friction in the barrel and on the fusee pivots, a more easy and uniform
transmission of the maintaining power is obtained, and the movement of the
chain will be regular, instead of in a series of jumps, as it is in the old arrange-
ment;. and. I am enabled to jewel the barrel, which could not be done with
safety under the old arrangement, on account of the danger of the jewels
breaking.
wt.
Having thus described the nature and particulars of the said.Invention, as
communicated to me, I desire it to be distinctly understood that I do not

page_text: confine myself to the precise details herein described, as such may be varied
or modified without departing from the principle of action thereof; but I
claim,―
1st. The escapement, consisting of a single escape wheel A, and two geared
balances B, B, with cylinders or cylindrical segments h, h*, engaging with
the said escape wheel on opposite sides of its axis, operating substantially as
herein set forth.
2nd. The compensating devices, consisting of the brass rings C, C, and the
surrounding coils D, D, of spring steel, with their forked ends m, m, applied
to the hair springs j, j, in the manner herein specified.
3rd. The arrangement of the chain relatively to the barrel and fusee, so
that the drag of the chain is on the same side of the axis of the fusee as
the resistance to the transmission of the power from the latter, as illustrated
in Fig. 2, whereby the friction on the fusee pivot is reduced, as herein set
forth.
4th. Arranging the two ends of the fusee in a position the reverse of that
heretofore adopted, as illustrated in Fig. 10, for the purpose of equalizing as
nearly as practicable the friction in both ends of the barrel and on the two
pivots of the fusee arbor at the time when the watch is fully wound, as herein
described.
In witness whereof, I, the said Alexandre Tolhausen, have hereunto set
my hand and seal, this First day of September, in the year of our
Lord One thousand eight hundred and fifty-six.
A. TOLHAUSEN. (L.S.)