IMPROVEMENTS CONNECTED WITH MARINE CHRONOMETERS
Year: 1880

page_text: LETTERS PATENT to John Sellar Matheson, of Leith, in the County of
Mid Lothian, North Britain, Chronometer Maker, for an Invention of
"IMPROVEMENTS CONNECTED WITH MARINE CHRONOMETERS,"
PROVISIONAL SPECIFICATION left by the said John Sellar Matheson at
the Office of the Commissioners of Patents on the 15th June 1880.
JOHN SELLAR MATHESON, of Leith, in the County of Mid Lothian, North
Britain, Chronometer Maker. " IMPROVEMENTS CONNECTED WITH MARINE
CHRONOMETERS."
This Invention relates to certain improvements connected with marine chrono-
meters, specially designed to admit of the winding of the same without the
necessity of turning over the instrument, as is usual, for the insertion of the
winding key, with the disadvantage that its action is interfered with.
The Invention consists essentially in attaching a small toothed wheel to the
ordinary winding square, underneath and outside the chronometer case, with which
a toothed pinion, fitted in the corner of the box in which the whole is enclosed,
may be put into gear when desired.
This pinion is preferably fitted on a vertical spindle the upper end of which is
made in the form of a key, and is free to slido vertically so as to be put into gear
with the winding wheel, or entirely out of gear and quite detached from or clear of,
the chronometer case when it oscillates on its gimbals, but held up in position for
winding by means of a sliding plate fitting in a small groove formed round the
key spindle, which plate can be moved out or in towards the groove and fixed by a
pinching screw.
To prevent the oscillation of the chronometer and keep the wheel and pinion in
gear for the winding operation, a sliding plate or pin jointed to the outer caso or
box is passed through a slot in the outer gimbal ring, and enters between
projections or a depression formed in the chronometer case, which steadies it
effectually.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Sellar Matheson in the Great Seal Patent Office on the
13th December 1880.
JOHN SELLAR MATHESON, of Leith, in the County of Midlothian, North-
Britain, Chronometer Maker. "IMPROVEMENTS CONNECTED WITH MARINE
CHRONOMETERS.'
"
My said Invention relates to certain improvements connected with marine
chronometers, specially designed to admit of the winding of the same without the
necessity of turning over the instrument, as is usual, for the insertion of the winding
key, with the disadvantage that its action is interfered with.
And in order that my said Invention and the manner of performing the same
may be properly understood, I have hereunto appended for that purpose a Sheet
of explanatory Drawings, representing a marine chronometer fitted with my
improvements, which I shall now proceed to describe. The same referenco letters
are used in these Drawings to indicate the same or like parts whero repeated.
Figure 1 is a vertical section through the chronometer holder or box 1, showing
the improved chronometer inside in front clevation; Figure 2 is a plan view of the
instrument with the lid of the box removed; and Figure 3 is an inverted plan of
the same showing the new winding gear applied.
Referring to these Drawings, the Invention consists essentially in attaching a s
small toothed wheel A to the ordinary winding square, or fusce arbor A¹ under-
neath and outside the chronometer case 2, with which a toothed pinion B fitted in
the corner of the box 1, in which the whole is enclosed, may be put into gear
when desired.
The pinion B is preferably fitted on a vertical spindle B', the upper end of
which is made in the form of a key B, and is free to slide vertically in bearings or
guides formed for it in bracket plates C and C¹, fixed to the outer box casing near
the top and bottom respectively. The pinion B is thus put into gear with the
winding wheel A, or in its normal position entirely out of gear, as shown in
Figure 1, and quite detached from or clear of the chronometer case 2, when it
oscillates on its gimbals 3, 4. The pinion B is held up in its position for winding
in gear with the wheel A by means of a sliding plate D, jointed by a pin & to the
bracket C, a notch D' surrounding and fitting in a small groove 6 being formed
round the key spindle B' to hold it. This plate D can be moved out or in towards
the groove b by a knob d³, and be fixed by means of a pinching screw D² 'passing
through a slot d³ in the plate D, to the bracket C in which it is screwed.
•
b
To prevent the oscillation of the chronometer and keep the wheel and pinion in
gear during the winding operation, a sliding or oscillating plate E, or it might be a
pin jointed to a bracket E' fixed to the outer case or box 1, is provided to pass
through a slot F in the outer gimbal ring 4, and enter between projections F", or a
depression or groove formed in the upper side or edge of the chronometer case 1,
which steadies it effectually, the plato E being moved by a pin e, and fixed in
either this inner position or out of action, as shown dotted by a pinching screw G,
forming its oscillating centre. The key B' may be fitted separately from the
spindle B, so as to be removed when not required for winding the chronometer;
and instead of a spur wheel A, and pinion B, bevil wheels or pinions may be used
for communicating the motion of the winding key to the fusce arbor A' to wind the
chronometer, without inverting or turning it on its gimbal centres.
The improvements can readily be applied to marine chronometers already in use
by extending the winding square or fusee arbor to enable a toothed wheel to be
fixed on it, and inserting the pinion, winding key, spindle, and fittings as shown in
the Drawings, to enable the chronometer to be wound without inserting or turning
it over.
]

page_text: Having now particularly described the nature and mode of performing my said
Invention, I have to state that what I believe to be novel and original, and
therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent is,―
First. The application and use in a marine chronometer of a toothed wheel A on
the winding square or fuses arbor, actuated by a wheel or pinion B on a movable
key spindle detached from the instrument, and the arrangement of fittings
connected therewith for putting the pinion into or out of gear, all substantially as
and for the purposes herein described in reference to the accompanying Drawings.
Second. As means for enabling marine chronometers to be wound without
inverting or turning them in their gimbals, the construction and fitting of such
instruments with a toothed wheel on the winding square or fusee arbor beneath,
actuated by a pinion and winding key spindle detached therefrom, substantially as
heroin set forth.
In witness whereof, I, the said John Sellar Matheson, have hereunto set my
hand and seal, this Ninth day of December, in the year of our Lord One
thousand eight hundred and eighty.
JOHN SELLAR MATHESON. (L.S.)