IMPROVEMENTS IN CHRONOGRAPHIC OR STOP WATCHES
Year: 1884

page_text: I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lako & Co, Patent Agents,
Southampton Buildings, London, in the County of Middlesex do hereby declare
the nature of said invention for "IMPROVEMENTS IN CHRONOGRAPHIC OR STOP
WATCHES" to be as follows:-
This invention relates to chronographs and has for its object to avoid the usual
expensive and complicated gear work used for working the chronograph hands
without stopping the watch. Some cheap chronographs are made without the said
gear-work but they cannot be used as watches and chronographs at the same time
because, to arrest the chronograph hands it is necessary to stop the watch. By
means of this invention I avoid this inconvenience and produce a cheap chronograph
which can be worked without stopping the watch movement which continues
independently of the chronograph movement.
lu carrying the said Invention into practice I provide a thin spring which is
arranged to act with a very gentle pressure on a raised Bat shoulder of a heart-
shaped piece through which the centre arbor of the watch passes. The said thin
spring is attached at one end to the plate of the watch in any suitable manner.
The free end of the said thin spring is inclined and a pin attached to one end of a
spring arm is adapted to act thereon. This spring-arm is operated by a ratchet-
wheel, which is by means of suitable connections operated from outside the case of
the watch when it is desired to start or stop the chronograph hands.
When the said ratchet wheel is rotated, recesses or projections thereon are caused
to act upon the said spring arm forcing the same outwards and causing its pin to
slide up the incline upon the end of the thin spring and force the same downwards
upon the shoulder of the heart shaped piece which carries the chronograph hand,
thereby stopping it; when the said spring arm returns to its normal position the
pin also retreats enough to allow the thin spring to rise sufficiently to free the
heart shaped piece from pressure permitting the chronograph hands to move round
with the watch movement thus avoiding the usual expensive gear-work. This
heart-shaped piece fits on the centre arbor or post of the watch and moves round

page_text: therewith except when arrested by the thin spring as described. When arrested
the said arbor or post moves freely within this heart-shaped piece, so as not to stop
the watch movement.
Some chronographs have two heart-shaped pieces arranged upon different
arbors of the watch, in this case the thin spring is adapted to bear upon both
simultaneously.
I do not confine theso improvements to one special kind of chronograph for they
will be found effective, serviceable and preferable in many kinds. The style or the
position of the thin spring may be altered to suit varying circumstances but the
action and the object of the heart shaped pieces always remain the same.
The watch-hands can work from the arbor of the chronograph hand if desired.
Dated this Seventh day of January 1884.

page_text: In some cases I provide a chronograph with two heart-shaped pieces barranged
upon different arbors of the watch, as shewn, for instance. In this case the spring a
is adapted to bear upon both of the said pieces simultaneously.
I do not confine these improvements to one special kind of chronograph as they
will be found effective, serviceable and of advantage in many kinds of chrono-
graphs. The form or the position of the thin spring may be altered to suit varying
circumstances, but the action and the object of the heart-shaped piece always remain
the same.
The watch hands can be arranged to work from the centre arbor carrying the
chronograph hand, or from an independent arbor as in the drawing.
I am aware that other chronographic or stop watches have been constructed
wherein the chronograph hand has been adapted to act independently, that is to
Bay, withont stopping the movement of the watch. The main object of my
invention is, however, to considerably simplify and cheapen the mechanism requisite
to effect this object.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what
I claim is -
First. In a chronographic or stop watch, the combination of the spring or
piece a and one or more heart-shaped pieces b substantially as above set forth and
means for operating the same as, and for the purpose, specified.
Second. The combination of parts comprising the spring arm or picce e having
the pin or projection e¹, the ratchet-wheelf, and means for actuating the same from
the outside of the watch, substantially as, and for the purpose, set forth.