IMPROVEMENTS IN CLOCKS
Year: 1877

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street, in the City
of London, Patent Agent and Consulting Engineer, for the Invention of
"IMPROVEMENTS IN CLOCKS." A communication from abroad by Charles
Delagrave and Louis Maximilien Grignon, both of Paris, France.
Sealed the 9th April 1878, and dated the 6th November 1877.
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn at
the Office of the Commissioners of Patents on the 6th November 1877.
<<
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. IMPROVEMENTS IN CLOCKS." A communication
from abroad by Charles Delagrave and Louis Maximilien Grignon, both of Paris,
France.
The primary object of this Invention is to make a universal geographical clock.
This clock comprises an ordinary dial of glass or crystal with its hands, the dial
allowing to be seen through it a terrestrial planisphere surrounded with a synoptical
ring on which are marked the names of the chief cities of the world. Outside this
planisphere is an annular dial of larger diameter, which turns in a reverse direction
to the hands and makes one revolution in 24 hours. This dial is divided into 24
parts; 12 divisions correspond to the hours of the day, and the other 12, which are
tinted or shaded, correspond with the hours of the night. The figure XII. on the
the white part indicates noon, and the same figure on the shaded part indicates
midnight.
In order to impart rotation to the outer dial, special mechanism, as about to be
described, is adopted.
On the central arbor or "long rod" is placed, with hard friction, the minute
wheel, the socket of which carries the minute hand; this wheel makes one revolution
every hour. The hour wheel is free on the socket of the minute wheel; its socket
carries the hour hand, and it makes one revolution in 12 hours. The minute wheel
[ Prins edil

page_text: gears with another minute wheel of the same diameter, on which is a pinion which
works the hour wheel. These are the wheels of the ordinary movement.
On the second minute wheel, above mentioned, is another wheel of smaller
diameter, but with the same number of teeth; it gears with a large wheel of double
the diameter. This latter carries a pinion which gears with another wheel; in
consequence of the difference of diameter of the two preceding wheels, this last
wheel makes only one revolution in 24 hours; it is upon the socket or arbor of this
wheel that the outer dial, before described, is fixed, and in consequence of the
arrangement of the gearing the rotation of this dial is from right to left, or the
reverse of that of the hands.
I adapt to these clocks a special remontoir which allows of winding up the barrel
of the hands or going part and the barrel of the striking part at the same time.
For this purpose the two arbors by which the winding up is effected each carry a
pinion with which gears a wheel worked by another pinion, the spindle or arbor of
which is, opposite a hole in the clock case; the arbor of the wheel carries a ratchet
wheel with a click fixed to a bridge or plate.
For some clocks I employ a rather different arrangement of remontoir but which
likewise winds up both parts at the same time; in this case the pinions on the
two winding arbors and the wheel with which they gear, as above described, have
ratchet teeth, and in connection with each of the pinions is a click. To the said
wheel is fixed another ratchet wheel of larger diameter, and on the arbor or axis of
these wheels a hand lever is fitted, this lever being provided with a click which
takes into the teeth of the larger wheel.
By giving oscillating movement to the handle, this click drives the two wheels,
and the motion is transmitted from the smaller wheel to the two pinions...

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Clayton Mewburn in the Great Seal Patent Office on the 18th
April 1878.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN CLOCKS." (A communication
from abroad by Charles Delagrave and Louis Maximilien Grignon, both of Paris,
France.)
The primary object of this Invention is to make a universal geographical clock.
This clock comprises an ordinary dial of glass or crystal with its hands, the dial
allowing to be seen through it a terrestrial planisphere surrounded by a synoptical
ring on which are marked the names of chief cities of the world. Outside this
planisphere is an annular dial of larger diameter which turns in the reverse direction
to the hands and makes one revolution in 24 hours. This dial is divided into 24
parts; 12 divisions correspond to the hours of the day, and the other 12, which are
tinted or shaded, correspond to the hours of the night. The figure XII. on
the white part indicates noon, and the same figure on the shaded part indicates
midnight.
In order to impart rotation to the outer dial special mechanism is adopted.
Figure 2 of the annexed Drawings is a front view, and Figure 3 a side view of
this mechanism.
Figure 1 represents the front or face of the clock.
The outer ring A, divided into 24 hours, turns in the direction of the arrow
under a glass disc, behind which are the ring B, on which the names of cities are
marked, the ring C divided into 12 hours like ordinary dials, and the central
planisphere D.
"
:-
The mechanism of the dials is arranged as follows:-
On the central arbor or long rod" a is placed, with hard friction, the minute
wheel b, the socket of which carries the minute hand c; this wheel makes one
revolution every hour. The hour wheel d is free on the socket of the minute
wheel; its socket carries the hour hand c¹, and it makes one revolution in 12 hours.
The minute wheel a gears with another minute wheel e of the same diameter, on
which is a pinion f which works the hour wheel d. These are the wheels of the
ordinary movement.
On the minute wheel e is another wheel g of smaller diameter but with the same
number of teeth; it gears with a wheel h of double the diameter. This latter
carries a pinion f¹ which gears with another wheel k. In consequence of the
difference of diameters of the wheels g and h, the wheel k makes only one revolution
in 24 hours; it is upon the socket or arbor of this wheel that the outer dial A is
fixed, and in consequence of the arrangement of gearing the rotation of this dial is
from right to left, or the reverse of that of the hands.
adapt to these clocks a special arrangement which allows of winding up the
barrel of the hands or going part and the barrel of the striking part at the same
time. For this purpose the two arbors i and i¹ each carry a pinion and with
which gears a wheel m worked by a pinion n, the spindle or arbor of which is
opposite a hole q (Figure 1) in the clock case; the arbor of the wheel m carries a
atchet wheel with a click s fixed to a bridge or plate p¹.
For some clocks I employ a rather different winding-up arrangement, but which
ikewise winds up both parts at the same time. This arrangement is represented
n Figure 4. The wheel and pinions m, l, and have ratchet teeth, and in con-
ection with each of the pinions 7, 1, is a click t and t¹. To the wheel m is fixed
nother ratchet wheel u of larger diameter, the two wheels being united by means
f the screws v. On the arbor or axis of these wheels a hand lever x is fitted, this
ever being provided with a click y which takes into the teeth of the larger wheel u,
eing acted upon by the spring z.

page_text: By giving an oscillating movement to the handle, this click drives the two wheels,
and the motion is transmitted from the smaller wheel to the two pinions.
I have not described the internal mechanisin of the clock as it may be of any
ordinary construction.
And having now described the nature of the said Invention and in what manner
the same is to be performed, I declare that I claim,-
First. The construction or manufacture of a universal geographical clock, con-
sisting, firstly, of an ordinary clock dial with its hands; secondly, of a terrestrial
planisphere surrounded by a synoptical ring on which the names of chief cities are
marked; and, lastly, of an outer ring divided into 24 parts, and turning in the
reverse direction to the hands, all substantially as herein-before described and repre-
sented in the annexed Drawings.
Second. The mechanism by which the outer ring is caused to make one revolution
in 24 hours, and from right to left, substantially as herein-before described and
represented in the annexed Drawings.
Third. The winding-up arrangement, herein-before described, and represented in
Figures 1, 2, and 3 of the annexed Drawings.
Fourth. The winding-up arrangement, herein-before described, and representëd in
Figure 4 of the annexed Drawings.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set my
hand and seal, this Seventeenth day of April, One thousand eight hundred
and seventy-eight.