IMPROVEMENTS IN PERPETUAL CALENDARS TO BE USED EITHER SEPARATELY OR IN CONNECTION WITH WATCHES OR CLOCKS
Year: 1861

page_text: PROVISIONAL SPECIFICATION left by Samuel Berchtold at the Office of
the Commissioners of Patents, with his Petition, on the 12th July
1861.
I, SAMUEL BERCHTOLD, of Number 48, Frith Street, Soho, in the County
of Middlesex, Watch Maker, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN PERPETUAL CALENDARS TO BE USED EITHER
SEPARATELY OR IN CONNECTION WITH WATCHES OR CLOCKS," to be as follows:-
My improved perpetual calendar for indicating the days of the week, the
days of the month, the months and periods of bissextile years, may be connected
with and form part of a clock or watch, by the works of which it is actuated, or
it may be made and used independently of such watch or clock and actuated by
other machinery or by hand. The mechanism of the calendar is set in motion.
by means of a click lever, one end of which takes into the teeth of a ratchet.
wheel. This wheel is the day-of-the-month wheel, and it is made with. 31. or
more teeth, and every time the lever is drawn out of contact with the teeth
of the wheel, and by means of a spring again caused to enter between them,
which is done once each day, this wheel is moved one tooth. The day-of-the-
month wheel moves loosely on an arbor with a pinion, and to this. pinion a disc
is fixed which can turn freely in the interior of the day-of-the-month wheel.
On the rim of this disc a three armed click is attached, one arm of which hooks
into the teeth of the day-of-the-month wheel and is retained in this position by
means of a spring pressing on the second arm of the click. By means of this
click the disc is carried along with the day-of-the-month wheel, and the hand

page_text: fixed to the other end of the arbor is thus taken round through the month
from the first to the last day of the same. There is a stud fixed to the watch
plate or frame close to the circumference of the day-of-the-month wheel and
the three armed click, being carried round with the wheel as described; on the
last day of the month, the third arm of the click, which reaches beyond the
circumference of the wheel, will strike against the said stud, and cause the
second arm of the click to withdraw from the teeth of the wheel. The disc,
arbor, and hand will thereby become disconnected from the day-of-the-month
wheel, and by means of a rack or wheel segment, actuated by a spring and
gearing into the pinion, carry back the hand to the first day of the month. On
the pivot of the rack or wheel segment an arm is fixed, to the end of which a
long hook is attached, which hook takes into a wheel of twelve teeth, for indi-
cating the months. To this months' wheel a disc is fixed whose circumference
is shaped according to the number of days of each month. Now the pinion
with arbor having been liberated from the day-of-the-month wheel as de-
scribed, the wheel segment with the arm and hook will likewise move backwards,
and in doing so the long hook attached to the arm will carry along with it one
tooth of the month wheel.
Another lever fixed on an arbor hinged to the frame, and the end of which
rests on the periphery of the month disc, against which it is pressed by a spring,
is, according to the position of the month disc, raised or depressed, and a
second lever is fixed to the same arbor, having on its end three notches, each
notch corresponding in shape with the teeth of the month wheel. Then accord-
ing to the position which the periphery of the month disc causes this notched
lever to occupy, one of these notches is presented to the three armed connect-
ing disc, one, two, or three days sooner, and disconnects the month day hand
at the moment the click touches the notched lever, and thus produces the
necessary number of days of the month. For producing and indicating the
29th day of February in bissextile years there is a star or wheel with
four points or teeth, upon which teeth a stud fixed to the month wheel acts,
and from December to January moves one tooth forward. This wheel or star
also carries a disc, three parts of the circumference of which is circular, the
fourth part being enlarged and forming an excentric or cam which passing once
in four years under the end of the lever which regulates the months, causes it to
present that notch of the lever which corresponds with the twenty-ninth day
of the month. The day-of-the-month wheel of my improved calendars being
moved forward only one tooth per day, the power furnished by an ordinary
pocket watch is sufficient to keep them in motion. In the calendars hitherto
made, the wheel has to make twelve revolutions per year or 372 teeth, in

page_text: addition to which they have to be moved forward three times in four years,
four teeth at a time, which requires considerably more power than can be
spared in the work of a watch. The principal feature of my Invention consists
in the manner in which the day-of-the-month wheel is connected with the
month wheel, so that reciprocally one acts upon the other, thus producing the
necessary number of days for each month.