Year: 1887

page_text: Date of Application, 18th May, 1887.
Specification Accepted, 22nd July, 1887.
I, JOSEPH ROBINSON, of No. 42 Canterbury Road, Croydon, in the County of
Surrey, Gentleman, do hereby declare the nature of this Invention, and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
This Invention relates to improvements in watches and the object thereof is to
prevent the same from being overwound. The Invention is specially applicable to
watches or timekeepers constructed on the 'Waterbury' principle with few working
parts and springs of unusual length.
In order that my Invention may be more fully understood I have hereto annexed a
sheet of Drawings illustrative thereof.
Figure 1 represents the back of a watch from which the outer case has been
removed so as to expose the spring plate or barrel.
Figure 2 is a front view of the spring plate.
Figures 3 and 4 are details shewing the parts in different positions.
A represents the casing of the watch which is notched around the inner rim a and
B is the spring plate or 'barrel which in this case is formed with teeth around the
periphery which gear with a small pinion C attached to the stem of the 'winding-up'
stud D as is usual in Keyless watches.
Upon the back of the spring plate is pivotted near the edge a catch E one end of
which is bent at a right angle and passes through a slot e in the plate. A spring F
having a wedge shaped end f, is let into the plate or may be cut out of the metal of
the plate itself.
It will be seen from Figure 2 that the spring G is doubled under at the end which
is attached to the projecting lug b, the spring proper passing over or outside the bent
end of the catch lever E whilst the short end G₁ of the spring presses against the
D

page_text: other side of the said part e¹ which is therefore under the influence of two springs
acting in opposite directions and being controlled by the wedge shaped end of the
spring F.
The action of the apparatus is as follows: When the watch has been wound up to
such an extent that further winding wound accelerate the speed thereof and so impair
its regularity as a timekeeper, the spring G acting on the end e¹ of the lever E
overcomes the resistance of the springs F and G₁ and causes the outer end of the
catch to project beyond the periphery of the spring plate and engage with one of the
notches in the case and so prevent further revolution of the spring plate.
The parts will remain in this position until the tension on the spring becomes so
much relaxed by the movement of the watch as to permit the spring G¹ to force the
pieco e¹ from under the end of the spring catch F and so disengage the outer end of
the lever E from the notch in the case.
It will be readily understood from the foregoing description that the extent to which
the watch can be wound-up or the amount of tension which can be put upon the
spring depends on the strength of the springs F and G as the winding must cease as
soon as the tension on the main spring G is sufficient to overcome the resistance
offered by the springs F and G¹.
I do not limit myself to the precise form of apparatus herein shewn as the same may
be slightly varied without departing from the spirit of my Invention, but
Having now fully described the nature of my Invention and the manner in which
the same is to be performed, I would have it understood that I claim :
The combination with a catch lever such as E actuated in one direction by the
mainspring G of a retaining spring such as F and a releasing spring such as G¹
operating in manner and for the purpose substantially as specified and illustrated in
the accompanying sheet of Drawings.
HUGHES, ELI & HUGHES,
76, Chancery Lane, London, W.C.,
Agents for the Applicant.