Timepiece with mechanism for setting the hands by direct action of the pull-out piece

Analogue display timepiece comprising a mechanism for hand setting via direct action of a pull-out piece (4) on an intermediate wheel (10) mobile along a shaft perpendicular to the general plane of the plate (P) of said timepiece between at least one neutral position in which said intermediate wheel (10) is disengaged from a motion-work wheel (20) and a hand setting position in which it meshes with said motion-work wheel (20), said intermediate wheel (10) being moved from one position to the other by translation of a hand setting stem (1) by being drawn at its base (12) by resilient means (15) into the hand setting position and being brought into a neutral position by an arm (7) of the pull-out piece (4) acting directly on the head (11) of the intermediate wheel in order to oppose the resilient means (15).

BACKGROUND OF THE INVENTION 
The present invention concerns a timepiece comprising a mechanism for 
setting the hands via direct action of the pull-out piece on a motion-work 
intermediate wheel, said mechanism allowing a rocking bar to be omitted as 
a result of the particular configuration of said pull-out piece. 
The invention concerns more particularly an analogue display watch fitted 
with such a hand setting mechanism. 
In order to carry out the disengagement of a motion-work intermediate wheel 
and conversely, the engagement or meshing thereof in order to perform hand 
setting, various mechanisms have been proposed. 
For example, Swiss patent No 583 933 discloses a mechanism wherein the 
disengagement of an intermediate wheel, held in a meshed position by a 
resilient tongue, is obtained via the action of a conical shoulder at the 
end of the winding stem on the end of the intermediate wheel shaft. 
In other more common solutions, the movement imparted to the winding stem 
allows actuation of a pull-out piece which acts on an intermediate mobile 
element, generally formed by a rocking bar one arm of which causes the 
disengagement or meshing of an intermediate wheel with the motion-work 
wheel. This principle has given rise to numerous alternatives. By way of 
example, Swiss patent No 613 588 may be cited, wherein the disengaged 
position, also called the neutral position, or the meshed position for 
hand setting, is obtained via the vertical displacement, i.e. 
perpendicular to the general plane of the watch, of a sliding pinion by 
means of a bent strip acting as a rocking bar in a plane perpendicular to 
the general plane of the watch, said strip being itself acted upon by an 
arm of the pull-out piece which is controlled by the hand setting stem. 
SUMMARY OF THE INVENTION 
The mechanism according to the present invention belongs to the preceding 
category, but differs in that the kinematic chain is shorter as a result 
of a simplified construction wherein the intermediate mobile element, 
interposed between the pull-out piece and a sliding pinion to allow 
meshing or disengagement of the motion-work wheel, is omitted. 
The invention thus concerns a timepiece having at least one analogue 
display comprising a mechanism for hand setting by means of an 
intermediate wheel delimited by a head and a base mobile along a shaft 
perpendicular to the general plane of the plate of said timepiece between 
at least one neutral position in which said intermediate wheel is 
disengaged from a motion-work wheel and a hand setting position in which 
it meshes with said motion-work wheel, said intermediate wheel being moved 
from one position to the other by translation of a hand setting stem 
provided with a circular groove co-operating with a pull-out piece, 
characterised in that the intermediate wheel is drawn at its base by 
resilient means into the hand setting position and in that the pull-out 
piece comprises an arm able to act directly on the head of the 
intermediate wheel in order to oppose the resilient means and to bring 
said intermediate wheel into a neutral position. 
The resilient means are for example formed by a coupling spring. In the 
example which will be described in more detail hereinafter, the hand 
setting mechanism comprises a strip-spring one end of which is fixed onto 
the plate. 
When the pull-out piece is pivoted, the action of the pull-out piece arm on 
the head of the intermediate wheel is facilitated by giving the end of the 
arm an inclined shape outwards from the general plane of the timepiece and 
by arranging a chamfer on said end of the intermediate wheel. Equally, the 
arm of the pull-out piece may comprise a simple chamfer and the end of the 
intermediate wheel may have a conical or truncated shape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIGS. 1 and 2 show in perspective only the hand setting mechanism, 
respectively in a neutral position when the stem is pushed in and in a 
hand setting position when the stem is pulled out. The movement of the 
timepiece and its display means via hands are not shown since they are 
part of the general knowledge of the man skilled in the art. 
Referring to FIG. 1, it is seen that the mechanism basically comprises, on 
a plate P defining a general plane of the timepiece, a stem 1 allowing a 
pull-out piece 4 to be actuated, such pull-out piece acting directly on an 
intermediate wheel 10, which is mobile on a shaft 13 --visible in the 
cross-section figures--perpendicular to the general plane of the 
timepiece, by exerting pressure along the direction of shaft 13 against 
the resilient force of a coupling spring 15, thereby holding intermediate 
wheel 10 disengaged from motion-work wheel 20. In the neutral position, 
the motion-work wheel which drives the hand display is thus completely 
disengaged from the kinematic chain of the hand setting. Pull-out piece 4 
consists of a body 5 of generally elongated shape one end of which is 
pivoted on the plate on a stud 3 and comprises a control arm 6 oriented 
substantially perpendicularly to body 5 and co-operating with a circular 
groove 2 of stem 1, and the other end of which comprises a second arm 7, 
having an end 8 which is inclined outwards from plate P. 
In the neutral position shown in FIGS. 1, 3 and 4, arm 7 abuts head 11 of 
intermediate wheel 10 by opposing the contrary force exerted by 
strip-spring 15 the free end 16 of which acts upon base 12 of the 
intermediate wheel and the other end 17 of which is attached to the plate, 
so that motion-work wheel 20 is disengaged from the intermediate wheel. 
In the hand setting position shown in FIGS. 2, 5 and 6, stem 1 has been 
pulled in the direction represented by the arrow in FIG. 2, which has 
caused the pivoting of pull-out piece 4 about stud 3, thus allowing bent 
end 8 of arm 7 to release intermediate wheel 10 which moves via the action 
of spring 15 along its shaft 13 to mesh with motion-work wheel 20. 
FIGS. 3 and 5 are top views corresponding to the positions shown in FIGS. 1 
and 2 and allowing the operation of the mechanism according to the 
invention to be better understood. 
Referring now to FIG. 4, the cross-section along the broken line IV--IV of 
FIG. 3 shows successively, from left to right, the plate, then the median 
part of the control arm 6 up until stud 3, body 5 of pull-out piece 4 up 
until arm 7 and finally intermediate wheel 10 the base 12 of which is 
acted upon by coupling spring 15 which is attached to plate P via its end 
17. It is to be noted that this strip-spring may be a resilient part 
assuring only the coupling or meshing function, or conversely, an element 
of a part assuring other functions, such as a arm of a jumper. Likewise, 
pull-out piece 4 may comprise meshing elements for other functions as is 
shown schematically by pin 9, visible in the perspective views and the top 
views. 
As regards the hand setting kinematic chain, FIGS. 3 and 4 also show a 
first intermediate wheel 21 meshed with a second intermediate wheel 22, 
which is itself permanently meshed with intermediate wheel 10, whatever 
its position along its shaft 13. 
FIGS. 6 and 7, which are respectively the views along the cross-section 
VI--VI of FIG. 5 and along cross-section VII--VII of FIG. 3, show even 
more clearly the position of the various wheels and pinions, respectively 
in the hand setting position and the neutral position. The arrows shown in 
these figures show respectively the direction in which the force of spring 
15 is exerted in the hand setting position and the direction in which the 
pressure of arm 7 of pull-out piece 4 is exerted in the neutral position. 
In a known manner, the first intermediate wheel 21 comprises a crown-like 
toothing which meshes with a pinion (not shown) mounted on a square 
portion 24 of control stem 1, said pinion being generally a sliding 
pinion. 
The hand setting mechanism according to the invention thus offers an 
economical advantage by omission of a rocking bar, a construction 
advantage by achieving a gain in space connected to said omission and an 
advantage as regards the longevity of the timepiece, given that the 
kinematic chain is at rest in the neutral position. This last point also 
contributes to reducing the driving torque of the hands by the motion-work 
wheel, and thereby the energy consumption, which constitutes a certain 
advantage, in particular in the case of an electronic timepiece supplied 
by a battery.