Improvements in and Connected with Spring Barrels for Watches and the like.
Year: 1888

page_text: Date of Application, 13th Oct., 1888
Specification Accepted, 30th Nov., 1888
COMPLETE SPECIFICATION.
Improvements in and Connected with Spring Barrels for Watches
and the like.
I, PAUL PERRET, of Chaux de Fonds in Switzerland, Watch Manufacturer, 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, reference being had to the accompanying drawings and to the letters and
figures marked thereon, that is to say :-
My invention relates to a construction of spring barrels, and to a system of fixing
the main-spring to the spring barrel, which are important features for the purpose of
having a regular and complete working of the main-spring.
In the drawings, Figs. 1 and 2 shew in section, and in plan, a main-spring barrel
of my improved construction. Figs. 3 and 4 shew in plan, and in elevation, the end
of the main-spring which is to be attached to the improved barrel. Figs. 5, 6 and 7
shew different variations of the same construction.
In all the figures the same letters refer to the same pieces.
g
On the main-spring axis a, are adjusted the barrel t, and its cover c. The latter is
provided with two recesses into which are placed the stop finger d and the star wheel m.
The pivot of the latter is formed by a cylindrical projection 9 with which is provided
the corresponding recess; no screw is used for this purpose and the said pivot is
stronger than the usual pivot screws. The winding-up wheel T,
which is affixed to the
main-spring axis, prevents the withdrawal of the stop finger d, and of the star wheel m.
In order to cause the barrel to turn freely, a small space is left between the stop
finger d and the cover c, and also between the star wheel in and the wheel r.
This described construction of barrel may, at will, be placed into the watch so as to
have the stopping train turned upward or downward.
To obtain a good working of the main-spring, this latter must have its windings
very regularly disposed in the barrel. For this purpose, I have devised the system
of, or means for fixing the spring to the barrel, as shewn in Figs. 3 and 4. To the
end of the main-spring f, 1 fix, by means of a rivet or pin e, a bridle b, of the shape
shewn in Fig. 4.
The purpose of the conical shape given to it being to render the
said bridle more elastic at its end. A projection i, with which the bridle b is provided,
enters a corresponding hole in the cover c, so as to prevent the unhooking of the
main-spring when the cover is in place.

page_text: In view of using larger springs, the barrel may be made withont a cover, as shewn
in Figs. 5 and 6. In such cases, as the now described combination of the projection i,
with a recess of the cover, is no longer possible, I fix the main-spring to the barrel by
means of the arrangement shewn in Fig. 7, the bridle bearing against the hook or
pin e in the barrel." In the construction shewn in Fig. 5, the barrel t is rotating and
the wheel fixed when the watch is going; in the construction shewn in Fig. 6 the
barrel is fixed, and the axis and wheel r are rotating when the watch is going. For
the purpose of diminishing the friction of the teeth of the barrel t in the recess of the
bridge, the latter is provided with a steel ring t¹.
Having thus described my invention I claim :
1st. The combination of the axis a with barrel t having its cover c provided with
two recesses for the stop-finger d and the star wheel m, the pivot of the latter being
formed by a cylindrical projection with which the corresponding recess of the cover c
is provided, and with wheel which holds the stop finger d, and wheel m in their
places, substantially as described and shewn.
2nd. The combination of the main-spring ƒ with a conical bridle having a rivet e
and a projection i, with a corresponding recess in the cover of the barrel, substantially
as and for the purpose specified.
3rd. The main-spring axis a with coverless barrel t and the wheel r shewn in Fig. 5
in combination with the arrangement of the bridle b shewn in Fig. 7, substantially as
described and shewn.
4th. The combination of the main-spring axis a and coverless barrel t, with the steel
ring & diminishing the friction of the teeth of barrel t in the recess of the spring barrel
t¹
bridge, substantially as described and shewn.
Dated is on day of October 1000.
ERNEST DE PASS, Fel. Inst. P.A.,
68, Fleet Street, London,
Agent for the Applicant.