IMPROVEMENTS IN THE CONSTRUCTION OF CLOCKS OR TIMEKEEPERS
Year: 1862

page_text: LETTERS PATENT to William Edward Gedge, of the Firm of John Gedge
and Son, of No. 11, Wellington Street, Strand, in the County of Mid-
dlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF CLOCKS OR TIMEKEEPERS."-A communication from abroad
by Pierre Louis Rabiet, of Châlon-sur-Saône, France.
COMPLETE SPECIFICATION filed by the said William Edward Gedge at
the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 29th November 1862, pursuant to the 9th Section of
the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD GEDGE, of the Firm of John Gedge and Son, of No. 11, Wellington
Street, Strand, in the County of Middlesex, Patent Agent, do hereby declare
the nature of the Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF CLOCKS
OR TIMEKEEPERS," (a communication to me from abroad by Pierre Louis
Rabiet, of Châlon-sur-Saône, France), and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Sheet of Drawing
hereunto annexed, and forming part of this Specification, and to the numerals
placed thereon to indicate different parts of this Invention.
For the better comprehension of these improvements and their results,
I would first remark that there are in ordinary clocks two very distinct bodies

page_text: of wheelwork placed parallel to each other, one being called the movement,
and the other the striking work. In the movement that which is properly
called the wheelwork is the arrangement of four wheels upheld perpendicularly
between two columns, where they receive motion from a weight of eight or ten
pounds. This Invention destroys the parallelism of these wheelworks, firstly,
by suppressing the two first wheels of the movement, and therefore the eight
or ten pound weight which acts on the first wheel, and then, because the two
remaining wheels of the movement (1 and 2), which are of a somewhat small
diameter for economy of work and power, are carried beneath the dial to the
front of the first column, where the point (3) or a small straight column (3*)
upholds them. The unoccupied space being thus enlarged permits the placing
of the first wheel of the striking work (4) in the centre of the clock frame or
cage. Although this wheel is the only remontoir wheel, and the principle or
source of the whole impulsion, it must, as before, tooth into the first pinion (5)
of the striking work. But previous to setting forth the means by which these
reductions are made up, I would observe that the striking wheel work is
preserved as hitherto, that is to say, that it preserves its three wheels, the star
wheel and the fly, then the pinion, which, as above stated, gears into the first
wheel of the striking work, has seven teeth and carries a star (6) which gives
fourteen hours each turn. As the striking work in working all round the
dial must strike 168 blows, it necessarily follows that the pinion and the star
must turn twelve times in twelve hours to strike this number of blows. Now,
if a second pinion with fourteen teeth (7) is placed on the first wheel of the
striking work, as the number of teeth is double that of the first pinion, it will
only turn half as many times as this latter, say, six times in twelve hours;
therefore, if the shaft of this fourteen-toothed pinion be arranged as a barrel
arbor it will be readily understood that this arbor in turning under the action
of the weight of the striking work may enrol around its cylinder six coils of a
spring of inferior strength, which is hooked to it, consequently, if this spring
is made the motor of the movement, it cannot be doubted that this motor will
be wound up regularly six turns in every twelve hours by the first wheel of
the striking work, and it follows that if a spring is used for motor the weight
is no longer required and is suppressed, and if the first wheel of the striking
work winds up this motor there is no occasion for the first wheel of the move-
ment or its accessories, they are therefore also dispensed with.
I will now explain the suppression of the second wheel of the movement.
To comprehend the. inutility of this wheel it must be known that in all clocks
the axle of the fourteen-toothed pinion above mentioned always carries two
wheels, one being the first wheel of the movement, and the other the wheel of

page_text: the dial work. These two wheels turn in the same direction, and each takeś
two hours to complete a revolution; this analogy of work rendering one of
them unnecessary, the second wheel of the movement is in this Invention
suppressed; it but served to conduct the pinion called of the crown wheel,
which the first wheel (8) of the dial work can well accomplish without
curtailing the functions of the hands, as I will demonstrate after explaining the
formation of the wheelwork. To form this wheelwork it must be remembered
that the motor is wound up by the striking work six turns in twelve hours,
and that the first wheel of the dial work makes invariably six turns in
the same lapse of time, therefore if this wheel is fixed to the arbor (9) the six
turns which this motor will develop during one circuit of the dial will always
be followed by six turns of the dial-work wheel, which will communicate the
impulsion to the pinion it has received, and this latter will necessarily transmit
it to the two wheels of the movement which follow it, and the wheelwork of
this Invention is formed.
I will next explain the movement called that of the crown wheel and of
the hands by the first wheel of the dial work. For this purpose the first
wheel of the movement is placed on a simple rod, on which is fitted the
pinion called of the crown wheel, which is retained in front by a pin.
Then, on the other side of the said pinion is placed a spring with four or six
branches (10), which, by its friction forces the wheel to turn with it as long
as the natural march of the movement continues; but if the hand is turned
the first wheel of the dialwork follows, bringing with it the pinion, which
causes the wings or flys of the spring to slide against the flat of the wheel
as long as the setting continues, and when the hand is released the whole
resume their functions. During the turning of the hand the motor obeys the
first wheel of the dial work as this obeyed the motor during the natural march
of the movement. In fact, retarding minutes, seconds, or thirds is, without
being aware of it, winding up the motor as much as the hands have been
retarded; whereas, if they are advanced the motor will unwind to an equal
extent, but in compensation it will have to that extent neared the point at
which the striking work will restore it the necessary tension. It is thus that the
reductions are made up, and instead of a movement requiring up every eight
days, this Invention offers with fewer pieces less gearing and less trouble, a
movement which will march perfectly without ever requiring winding up.
The main detent (11) is replaced by the following arrangement:-The main
detent (11) is composed of a rod placed between the columns, and a little
above the wheel which carries the large hand, from thence this rod by one of
its extremities advances a squaro, which receives a piece of steel shaped as a

page_text: hook scapement (12), while the other extremity of this same rod carries a
band or arm with heel (13), which at the beginning of the working goes to
and across the pin (14) carried by the pinion of the fly (15), as soon as the
wheel (16) of the fly is by the heel sufficiently freed from the catch (17).
Then the wheelwork is held in this state, firstly, until the fall of the rack (18),
and when this falls there follows a further retard, during which the functions of
the striking work further form until the hook scapement escapes from the pin
(19) which presses it. Lastly, as soon as the hook scapement becomes free, the
detent falls again into its place, not only brought back by its weight, but also
pushed by the fly which it held before completing the setting of the striking
work. All this is effected in two minutes, at moments so distinctly fixed,
and with so much certainty, that it would be impossible to doubt the action of
this striking work. If by inadvertance in striking the hour the hand should
be carried beyond the repeating point, it may be brought back, and when it
has repassed the same point all will be repaired. With this object in view, a
small spring is placed behind the hook scapement, otherwise this. agent would
be useless to the detent, which, although extremely light, suffices for all the
work with which it is charged.
I will now describe the repeating:-The repeating is effected very nearly
according to the preceding rules by a pin (20) placed in the centre of the
hook scapement, which to repeat crosses an acute angle (21) projecting above
the wheel which carries the large hand. I have above stated that these effects
resemble entirely those of the hour.
The next part of this Invention which I will proceed to set forth is the
fitting of the spring before the seventh hour, and its slight developement. If
the strokes of the hammer during a circuit of the dial be divided into two
periods, counting the hours and the quarters, it will be found that the greatest
depression or running down of the motive power of the striking work must be
fixed a little before the seventh hour. In fact, if starting from seven o'clock,
the striking work goes on until after twelve is struck, it will have given 119
blows. As the movement only requires fourteen each hour to keep it going
during this first period, it will have acquired 35 strokes more than it has
expended, and the motor will be at its apogee; but thenceforth the striking
work, returning, to its point of departure, will during this second period strike
but 49 blows, and then the movement will have lost the 35 strokes that the
motor had acquired. It is, therefore, a little before seven o'clock that the
greatest depression of the motive power takes place, and it is from this point
the motor should be started. If we now examine the value of the 35 strokes
of the hammer which remain with the motor from the first period of the going

page_text: of the striking work, we shall ascertain the slight developement it takes. I
have above stated that fourteen strokes suffice to keep the movement going for
one hour, therefore the 35 strokes of the hammer which carry the winding up.
of the motor to its apogee represent two hours and a half of the working of
the movement,, which is equivalent to a tension of one turn and a half more,
than when set. Such is the solution which establishes that the movement
forming part of this Invention more nearly approaches a constant power than
any other pieces of spring clockwork.
The next part of this Invention which I will.describe is the stop piece. To
render the action of this piece apparent, wind up the mechanism, set the
spring two turns. before the seventh hour, by turning the large hand four turns
once for all, that is to say, wind up the movement for twenty or twenty-five
years, during which time it will keep going without repairs; lastly, suspend
the weight, start the pendulum or balance, the hand gives the hour, the
hammer strikes it, and the movement works conjointly with the striking work
as long as the weight. has, not run down; but if this weight were not raised
again at the end of eight days the striking would cease, and the movement
deprived of its help would only keep going, losing strength at each vibration
until the end of the tension of the motor, therefore, if, as above stated, the
movement marches conjointly with the striking work, it must stop at. the same
time. There is consequently placed between two columns of the cage or frame
a rod with pivots (22); which carries a band of metal (23), the end of which
bent into a square extends to, the pendulum or balance, as the cord of the
counterweight passes through an oval in this band the ring of the counter-
weight; which is larger than the oval, lifts: it at the last stroke of the hammer,
and the rod in form of square arrests the movement by touching two or three
pieces of spiral, united by a pin or bolt (24), carried interiorly by the arm. of
the balance. But as soon as the counterweight is pulled, the piece described
falls again into its place, and everything is. again set going. The purchaser.
requires no special instructions, only as the key is suppressed he will pull the
counterweight every eight days; the rest is mechanical, and is accomplished
unperceived.
:
I will now describe three escapements which form part of this Invention.. A
cross (25) is made of flat steel, its upper part being rounded to form a short
rod. The stem of the cross bar (26) is then, taken in the line of the short
rod, and is left definitively square. A square (27), is then formed, at the end
of which is the next short rod... Now if it is desired that the escapement take
four teeth of the wheel that conducts it, trace on the cross. bar two separate
lines of the breadth of these four teeth, leaving the upper short rod in the

page_text: centre, then pierce a square hole in the middle of each of these lines, to fit in
two projecting pieces of steel passing within the cross bar, above which they
are held by small. nuts. This done, pierce a third hole in the middle of a
square reserved in the stem or rod, and which is the place for the arm of the
escapement, further retained by the means above described. Then the cross
is ground smooth, tempered, and polished before the pivots are made; the first
plane is then formed, the second is essayed on the first; and, lastly, the two
are not completed until the escapement is put in its place. It will be evident
that this escapement (25 and 25*) is removed in parts, and that the pivots
may be repolished like those of a simple rod.
Second escapement, No. 28 in the Drawing.-The right arm of the cross is
lengthened more than in the preceding escapement, and is bent on itself, so
that it's extremity attains the level of the rod, between which it leaves an
opening. This arm' is made to form the first plane, and will serve as guide
for placing the second, which is fixed by a nut. The small upper rod is then
formed in the centre, and reserving the place for the arm of the escapement,
the rod or stem is established in line with the small rod; and is definitively left
square according to the thickness of the steel. Lastly, having rounded in a
lathe the place for the pivots, the two planes are so arranged that the escape-
ment may be tried in position before tempering:
Third escapement, No. 29 in the Drawing. This escapement is the most
preferable under the conditions of the first, that which afterwards creates
a difference is that it is of one piece, that is to say, that instead of bearing
a plane, the second arm of the cross is lowered a little out of square, and it
forms the second plane. It will be evident that this escapement is very
simple, and may be made exceedingly light. Being struck, it is formed in the
rough by a few strokes of the file. It works in the Invention with the same
advantage as the preceding. If later, and contrary to all expectation, it
should be deemed desirable to increase the motive power, this may be done
without changing the spring by substituting, firstly, a twelve to the fourteen
toothed pinion which forms the barrel arbor, which will then make seven
turns in twelve hours in lieu of six, which would add one-seventh more activity
to the movement. Then instead of the wheel of the large hand carrying 42,
it will carry 49 teeth, leaving 84 to the wheel of the dialwork. And it being
necessary to accelerate the action' of the rest of the movement the power of
the seven-toothed pinion will be replaced by one with eight, which would
conduct the escapement wheel, to which sixty vibrations would be given each
revolution. Those clocks made according to this Invention, but not being
repeaters, will require no change but in the weight and the toothing, and

page_text: when the winding up is effected by a key, the stop piece suffers some slight
modifications.
Lastly, this Invention may be applied to small clocks, in which case a
spring would be substituted for the weight of the striking work, and the
pendulum would be shortened by changes in the toothing. With regard to
the stop piece above mentioned, it is replaced by a rack acted upon by
the spring of the striking work being fixed to the shaft or spindle of its
remontoir.
Having now described the nature of the said Invention, and illustrated
the same in the annexed Drawing, I will, in conclusion, recapitulate the most
important parts of this said Specification, which are,―
1. The establishment of the striking work in the centre of the cage.
2. The suppression of the first wheel of the movement.
3. Replacing this wheel, the spindle, the pulley, the clockwork, and the
weight by a watch spring, No. 37, winding up three times in the hour by the
action of the striking work.
4. Suppression of the second wheel of the movement by means of a toothed
gearing carried by the first wheel of the dial work.
5. Setting the motor by the large hand.
6. The suppression of the main detent, replaced by an extremely accurate
and certain piece.
7. The establishment of three species of anchor escapement, forming part
of this Invention.
8. Establishment of a stop piece, forcing the movement to travel conjointly
with the striking work.
9. Suppression of the key by a counterweight.
10. Establishment of a spring with four branches and reservoir.
Lastly, this Specification incontestably proves that this Invention more
nearly approaches constant power than any other spring clockwork hitherto
invented.
In witness whereof, I, the said William Edward Gedge, have hereunto
set my hand and seal, this Twenty-ninth day of November, in the
year of our Lord One thousand eight hundred and sixty-two.
W. E. GEDGE. (L.s.)
W. E. GEDGE. (L.S.)