CH710892A2 - chronograph mechanism for watch movement. - Google Patents

Abstract

The present invention relates to a chronograph mechanism including "return in flight", comprising a driving kinematic chain for connecting a driving wheel to a chronograph counter (6), a clutch device (8) comprising a body transmission device (10) movable between a first disengaged position, in which the driving kinematic chain is interrupted and a second engaged position, in which the driving kinematic chain is functional, a movable brake (30) for locking the chronograph counter (6), a resetting hammer (50) movable between a first resting position and a second resetting position, and comprising a first neutralizing portion (80) engageable with the transmission member (10) to force it to leave its engaged position when the reset hammer (50) is actuated, a second neutralization portion (84) capable of cooperating with the brake (30) to force it to leave its locking position when the reset hammer (50) is actuated.

Description

Technical area

The present invention relates to a chronograph mechanism, for a watch movement, comprising a driving kinematic chain capable of establishing a kinematic connection between a driving wheel of the watch movement and at least one chronograph counter, a clutch device comprising at least one movable transmission member between a first disengaged position, in which the driving kinematic chain is interrupted and a second engaged position, in which the drive kinematic chain is functional, a movable brake between a first position, in which it acts on the chronograph counter to lock it, and a second position, in which it is located away from the chronograph counter to leave it free to rotate, at least one reset hammer movable between a first rest position and a second reset position in which it cooperates with the chronograph counter to place it in a predefined configuration, first and second control members arranged to respectively control, on the one hand, the clutch device and the brake and, on the other hand, the reset hammer.

State of the art

Such chronograph mechanisms have been known for a long time and may have various constructions.

For example, the book entitled "Theorie d'horlogerie", of C.-A. Reymondin et al., Published by the Federation of Technical Schools (Switzerland), ISBN 2-940-025-10-X, pages, provides examples, including pages 232 to 244.

In these chronograph mechanisms, current type, the reset chronograph counters can be performed only when the mechanism is stopped in STOP configuration. For this purpose, the reset hammer generally has a spout arranged to cooperate with the control member of the clutch device and the brake and prevent actuation of the hammer when the measurement of a time is in progress. In addition, the hammer generally cooperates with the brake to lift it when actuating the reset.

An alternative embodiment of these mechanisms is known thanks to which a reset is also possible during the measurement of a time. These mechanisms are called "flyback".

In this case, it is necessary to provide a device for acting on the clutch device if the reset is actuated while the measurement of a time is in progress, to neutralize it and thus avoid causing damage to the mechanism.

The present invention relates to such a mechanism wherein the reset hammer is arranged in such a way that it is susceptible to be actuated independently of the respective positions of the transmission member and the brake, to force the brake to leave its first position, and to force the transmission member to leave its engaged position.

[0008] Patent CH 183 262 shows an example of construction of a "flying-back" type chronograph mechanism. In this mechanism, the reset hammer is arranged to act directly on the brake, if necessary during resetting operations, as in standard chronograph mechanisms, while a specific rocker is provided to act on the device. clutch and place it in its disengaged configuration if a reset is operated during the measurement of a time. Indeed, the reset hammer is generally remote from the clutch device, in the chronograph mechanisms, and the implementation of an intermediate specific rocker is necessary to transmit the movements of the hammer to the clutch device . In the construction disclosed in this patent, the reset hammer carries a pin therethrough from one side to act, on one side, on the brake and, on the other side, on the intermediate lever.

However, such a construction results in an increase in the number of components of the chronograph mechanism and makes it difficult to focus the latter. In addition, the increase in the number of components implies that they are distributed over several levels, depending on the thickness of the chronograph mechanism, which also leads to an increase in the total thickness of the mechanism, which is already important by default.

Disclosure of the invention

A main object of the present invention is to provide an alternative construction known constructions of the prior art, by proposing a chronograph mechanism of the type "return in flight" having a thickness and a difficulty of focusing limited with reference to known constructions.

For this purpose, the present invention relates more particularly to a chronograph mechanism of the type described above, characterized in that the hammer comprises a first neutralization portion capable of cooperating with the transmission member when the hammer is actuated, a second neutralization portion capable of cooperating with the brake when the hammer is actuated.

With these features, the hammer is shaped so that it can act directly on the clutch device, without the need to provide an intermediate flip-flop, thus limiting the number of components required with reference to the known mechanisms.

According to a preferred embodiment, the reset hammer comprises a return arm in flight carrying the first and second neutralization portions.

Advantageously, it can be provided that the reset hammer is substantially planar, the first and second neutralization portions being formed on a wafer of the return arm in flight.

It can then be provided that the transmission member and the brake each carry a substantially cylindrical stud intended to cooperate with one of the neutralization portions.

According to a preferred embodiment, when the reset hammer has a rotational movement to move from one to the other of its first and second positions, the first and second neutralization portions can advantageously have the shape of arcs centered on the axis of rotation of the reset hammer.

In this case, it can be provided that, in a plan view, the reset hammer is intended to be arranged substantially in a first quarter of the watch movement, while the transmission member and the brake are intended to be arranged substantially in another quarter of the watch movement. The flight return arm then advantageously has a curved shape intended to circumvent the center of the watch movement.

According to an alternative embodiment, it is possible to provide that the reset hammer comprises a base comprising a hole, defining its axis of rotation, and an actuating surface arranged to cooperate with the second control member, and from which extend at least one first arm carrying a reset surface arranged to cooperate with the chronograph counter, and the flight return arm, the latter comprising, from the base and towards its free end, a resting surface, a first inclined surface, the first neutralization portion, a second inclined surface and the second neutralization portion, and that the flight return arm is arranged in such a way that the resting surface is arranged facing one of the transmission member and the brake, and that the first neutralization portion is arranged facing the other of the transmission member and the brake, in the reset position of the reset hammer, and that the first neutralization portion is arranged facing one of the transmission member and the brake, and that the second neutralization portion is arranged facing the other of the transmission member and the brake, in the reset position of the reset hammer.

In general, the chronograph mechanism advantageously comprises a chronograph minute counter, the reset hammer comprising an additional arm carrying an additional reset surface arranged to cooperate with the chronograph minute counter for the chronograph minute. place in a predefined configuration.

The invention also relates to a watch movement comprising a chronograph mechanism that meets the characteristics that have just been exhibited, as well as a timepiece comprising such a watch movement.

Brief description of the drawings

Other features and advantages of the present invention will appear more clearly on reading the detailed description of preferred embodiments which follows, made with reference to the accompanying drawings given by way of non-limiting examples and in which: <tb> Fig. 1 <SEP> represents a simplified top view of a watch movement comprising a chronograph mechanism according to a preferred embodiment of the present invention, in a first configuration; <tb> fig. 2 <SEP> represents a simplified top view of the watch movement of FIG. 1 in a second configuration, and <tb> fig. 3 <SEP> represents a simplified top view of the watch movement of FIG. 1 in a third configuration.

Mode (s) of realization of the invention

Figs. 1, 2 and 3 show the same simplified top view of a watch movement 1 comprising a chronograph mechanism according to a preferred embodiment of the present invention, in first, second and third respective configurations, corresponding to the three operating modes. of the chronograph mechanism, that is to say respectively stop, walk and reset.

The watch movement 1 comprises a frame comprising a plate 2 and conventional bridges not shown in the figures for clarity. The watch movement 1 is represented here in a view of its platinum side, a winding stem 4 being assembled to a winding and setting mechanism (not visible) in a conventional manner, in the three o'clock position (according to convention usual based on the positions of the hours on a watch dial).

The chronograph mechanism is arranged on the plate 2, on its face oriented on the dial side.

Conventionally, a drive wheel (not visible) is provided to drive in rotation, on demand, the mobile chronograph mechanism to perform the measurement of a time.

A kinematic chain is provided to transmit, on demand, the rotational movement of the drive wheel to a chronograph seconds counter 6. The kinematic chain comprises a clutch device comprising a rocker 8 pivotally mounted on the constructing the watch movement between a first position, disengaged, and a second position, engaged.

The clutch rocker 8 carries a transmission member comprising, in the present preferred embodiment of illustrative non-limiting, a vertical reference 10 including a first wheel (not visible) is intended to mesh with or not with the mobile and a second wheel 12 is intended to mesh or not with a wheel 14 of the chronograph seconds counter 6. In known manner, the wheel 14 is secured to a shaft 16 of the chronograph seconds counter 6 intended to carry a second display member of a timed time (not shown).

Thus, the kinematic chain between the drive wheel and the chronograph counter 6 is interrupted in the first position, disengaged, of the clutch rocker 8 and functional in its second position, engaged.

The clutch rocker 8 comprises an elongate nozzle 18 arranged to cooperate, on one of its sides, with a rotary control member 20 having an operating mode similar to that of a conventional column wheel.

The control member 20 comprises for this purpose a first toothing 22, control, and a second toothing 24, actuation, made by the assembly of two stars, here one to four teeth and the other to eight teeth. The first toothing 22 is intended to make it possible to rotate a step of the control member 20 in response to an action of a user on a control lever 26. The second toothing 24 cooperates with the spout 18 of the clutch lever 8 to define the angular orientation of the latter. A return spring 28 acts on the clutch rocker 8 so that its spout 18 is arranged in abutment against the control member 20.

When the second toothing 24 has a tooth facing the spout 18, it acts on the nose to move away from the center of the control member 20 (disengaged position), opposing the action of the spring 28. When the second toothing 24 has a gap, located between two teeth, facing the spout 18, the clutch lever 8 pivots in the anti-clockwise direction of rotation, so as to bring its spout 18 closer to the center of the control member 20 (engaged position).

Furthermore, the chronograph mechanism also comprises a brake 30 rotatably mounted on the frame of the watch movement and intended to act directly on the periphery of the wheel 14 of the chronograph second counter 6, to lock it angularly in the configuration. stopped. For this purpose, a spring 32 is arranged to act on the brake 30 and push it towards the wheel 14.

The brake 30 is shaped such that it can cooperate with a screw 34 carried by the clutch rocker 8 so that the latter raises the brake 30 from its disengaged position to its engaged position.

This operation occurs when the chronograph mechanism passes from its stopped configuration to its gait configuration, as is apparent from a comparison of Figs. 1 and 2 . When the clutch lever 8 moves from its disengaged position to its engaged position, it raises the brake 30 while its wheel 12 engages with the wheel 14 of the chronograph second counter 6.

Conversely, when the measurement of a time is stopped, the clutch lever returns to its disengaged position as illustrated in FIG. 1 and release the brake 30, at the same time, which locks again the wheel 14 regardless of its orientation.

In known manner, the illustrated chronograph mechanism also comprises a chronograph minute counter 36 driven from the counter chronograph seconds 6. To this end, the chronograph mechanism comprises a reference 38 arranged in permanent engagement with the wheel 14 and carrying an actuating finger 40, elastic, intended to cooperate with the teeth of a wheel 42 of the chronograph minute counter 36, to drive a step every minute of a timed time. The wheel 42 is secured to a shaft 44 of the chronograph minute counter 36 for carrying a display member timed minutes (not shown).

Furthermore, the chronograph mechanism according to the present invention comprises various return springs and jumpers which will not be described in detail, as well as their functions, since they are well known to those skilled in the art.

The chronograph mechanism comprises a reset device comprising in particular two cams heart reset 46, 48, respectively integral with the shafts 16 of the chronograph seconds counter and 44 of the chronograph minutes counter.

The cams 46, 48 are intended to cooperate with a reset hammer 50 in a conventional manner.

The resetting hammer 50 is pivotally mounted on the frame of the watch movement, by means of a bearing screw 52, for pivoting between a first resting position (FIG 1 and 2), and a second reset position (Fig. 3). For this purpose, the hammer 50 comprises a base 54 in which is formed a hole (not visible) defining the axis of rotation of the hammer and through which is arranged the screw 52.

The base 54 carries an actuating surface 56 intended to cooperate with a hammer control member having the shape of a control lever 58 pivotally mounted on the frame of the watch movement, between a rest position and a position actuating means for resetting the chronograph counters in response to pressure exerted by a user on the control lever 58.

The hammer comprises a first arm 60, carrying a first resetting surface 62 for cooperating with the cam 48 of the chronograph minute counter 36, and a second arm 64 carrying a second resetting surface. 66 intended to cooperate with the reset cam 46 of the chronograph seconds counter 6.

Note that the reset hammer 50 does not interact with the first control member 20 as is generally the case in simple chronograph mechanisms, which allows to operate independently of the angular position of the control member 20 and therefore the current mode of operation, that is to say that the measurement of a time is in progress or not. As mentioned above, this type of chronograph mechanism is called "flyback".

A return spring 67 cooperates with the reset hammer 50 so as to push it towards its rest position. The spring 67 has a recess 70 in which is housed a pin 72 secured to the reset hammer 50 in the rest position of the latter. At the same time, the hollow 70 makes it possible to define a notch when the reset hammer 50 is actuated. When the control lever 58 is actuated and then released by a user, the return spring 67 acts on the delivery hammer. to zero 50 to push it back to its rest position.

As has been explained in connection with the prior art, a chronograph mechanism type "return in flight" requires the implementation of an arrangement to move the brake 30 and the clutch rocker 8 of the wheel 14 during reset operations to avoid any damage that might otherwise be the chronograph mechanism.

For this purpose, the reset hammer according to the present invention comprises a flight return arm 68 intended to act on both the clutch rocker 8 and the brake 30, when the hammer 50 is actuated. to move from its rest position to its reset position.

The flight return arm 68 extends substantially in a plane and comprises on its outer edge, or slice, from the base 54 towards its free end 74, a rest surface 76 followed by a first inclined surface 78 , a first neutralization portion 80, a second inclined surface 82 and a second neutralization portion 84.

In the configuration at the stop of the chronograph mechanism (FIG 1), the rest surface 76 is located opposite a stud 86 integral with the clutch rocker 8, the latter being however out of reach hammer 50 because of its cooperation with a tooth of the control member 20. In this configuration, the first neutralization portion 80 is located opposite a stud 88 integral with the brake 30, without being against it. The brake 30 is thus free to be positioned in abutment against the wheel 14 to lock it. The second neutralization portion 84 is for its part free of any interaction in the configuration of FIG. 1.

Note that, advantageously but not limited to, the stud 86 is here directly constituted by a portion of the shaft on which are rotated the wheels of the clutch device extending slightly beyond the hub of the second. wheel 12.

When the measurement of a time is initiated by actuation of the control member 20, as illustrated in FIG. 2 in the running configuration, the clutch rocker 8 pivots to drive the wheel 14. The reset hammer 50 then has a position unchanged from the position of FIG. 1.

It is found that the rest surface 76 does not intervene in the rotation of the clutch rocker 8, the distance between them at rest is sufficiently large. The brake 30 is then raised by the clutch rocker 8 and is removed from the first neutralization portion 80 which therefore still plays no role in the operation of the chronograph mechanism.

If the control lever 58 is actuated from the running configuration of the chronograph mechanism (FIG 2), the latter passes into the reset configuration, as illustrated in FIG. 3.

The action of the control lever 58 causes the pivoting of the reset hammer 50 in the anti-clockwise direction of rotation.

The resetting surfaces 62 and 66 then come into contact with the cams 46 and 48 to reset the two counters in a predefined angular orientation corresponding to a zero measured time, in a conventional manner.

During the fall of the reset hammer 50 to its reset position, the flight return arm 68 has the same rotational movement as the hammer for, at first, push the clutch rocker 8 and the brake 30 if necessary, through its first and second inclined surfaces acting on the pads 86 and 88, then, in a second step, position the first and second neutralization portions 80 and 84 facing the pads 86 and 88 and thereby keep the clutch rocker 8 and the brake 30 away from the wheel 14 of the chronograph seconds counter 6.

Note that if the zeroing is actuated in the configuration at the stop of the chronograph mechanism (FIG 1), in which only the brake 30 is arranged in contact with the wheel 14, the brake 30 only is moved by the return arm in flight 68, the first neutralization portion 80 being placed opposite the stud 86 of the clutch rocker 8 to ensure that the latter can not go into its engaged position without it being really necessary to push it further.

If the reset is actuated in the running configuration of the chronograph mechanism (FIG 2), in which only the clutch rocker 8 is arranged in contact with the wheel 14 via its wheel 12, the clutch lever 8 only is moved by the flight return arm 68, the second neutralization portion 84 being placed opposite the stud 88 of the brake 30 to ensure that the latter can not pass into position locking, bearing against the wheel 14. More specifically, as mentioned above, in the run configuration, the brake 30 is lifted from the wheel 14 directly by the clutch rocker 8, but the fact that the clutch rocker 8 being pushed back by the first neutralization portion 80 implies that the brake 30 could be free to fall on the wheel 14 without the intervention of the second neutralization portion 84 arranged to prevent it.

When the control lever 58 is released, after resetting the chronograph counters, the reset hammer 50 returns to its rest position, under the effect of the action of the return spring 67. In this movement, the flight return arm 68 has a reverse movement to what has just been described and releases the clutch rocker 8 and the brake 30 to return to the configuration of the chronograph mechanism that was in place before delivery at zero, either on or off.

Note that here the outer edge of the flight return arm 68 has different sections substantially in the form of circular arcs centered on the center of rotation of the hammer 50, with the interposition of the two inclined surfaces, to define the portions. neutralization. The flight return arm 68 therefore plays the role of a two-level cam arranged to act respectively on the clutch rocker 8 and on the brake 30.

Thus, a reset hammer construction that provides an optimal level of security for the implementation of the operation of flying back of the chronograph mechanism, but without presenting a complex structure and therefore expensive.

It will be noted in particular that the construction of the chronograph mechanism according to the present invention reduces its size in the direction of its thickness. Indeed, the reset hammer 50 can be made substantially in a plane thanks to the particular shape of its flight return arm 68 which allows the latter to co-operate simultaneously with the clutch rocker 8 and with the brake 30. In addition, the fact that the reset hammer cooperates directly with the clutch rocker rather than via an intermediate rocker as is the case in the mechanisms of the prior art, also allows to simplify the development and adjustment operations of the mechanism during its manufacture.

Furthermore, the architecture of the chronograph mechanism according to the preferred embodiment which has just been described is particularly advantageous. Indeed, the control members, respectively for on-off and reset, are arranged directly opposite the corresponding buttons, as they are typically located in timepieces chronograph function. More specifically, it is found that the control member 20 is located at two hours, substantially opposite the pusher on-off, while the actuating surface 54 of the hammer 50 is located around five o'clock, in the immediate vicinity of the pusher resetting, located him to the four o'clock position. Thanks to these characteristics, it is not necessary to use the use of intermediate intermediate rockers to retransmit the commands from the external buttons as is generally the case in known chronograph mechanisms. Such a feature contributes again to simplify the development of the mechanism during its manufacture. In addition, it can be seen from the figures that such an architecture makes it possible to arrange the reset hammer substantially in a first quarter of the watch movement, while the components involved in the running and stopping modes, in particular the flip-flop. clutch and brake, are arranged in a second quarter of the watch movement. The flight return arm then has a curved shape, intended to circumvent the center of the watch movement, to extend into the quarter in which are arranged the clutch rocker and the brake.

The foregoing description attempts to describe a particular embodiment by way of non-limiting illustration and, the invention is not limited to the implementation of certain particular features which have just been described, as for example the specifically illustrated and described forms for the components of the chronograph mechanism. In particular, it will be noted that the illustrated reset hammer has an advantageous form because the junctions between its different arms and its base are refined, thus giving some elasticity to the arms. The development and adjustment operations during the manufacture of the corresponding mechanism are again simplified.

The skilled person will not encounter any particular difficulty to adapt the content of the present disclosure to his own needs and build a chronograph mechanism of the type "return in flight" and in which the reset hammer is arranged to cooperate directly with the brake and the clutch device when a reset is actuated, without departing from the scope of the present invention.

For example, if the chronograph mechanism that has just been described is of integrated type (the basic watch movement), the skilled person may decide to adapt the present teaching to achieve a mechanism of modular type chronograph without difficulty and without departing from the scope of the invention.

Claims (10)

1. Chronograph mechanism, for watch movement (1), comprising a driving kinematic chain capable of establishing a kinematic connection between a driving wheel of the watch movement and at least one chronograph counter (6), a clutch device (8) comprising at least one transmission member (10) movable between a first disengaged position, wherein said drive kinematic chain is interrupted and a second engaged position, wherein said drive train workout is functional, a brake (30) movable between a first position, in which it acts on said chronograph counter (6) to lock it, and a second position, in which it is located remote from said chronograph counter (6) to leave it free to turn, at least one reset hammer (50) movable between a first rest position and a second reset position in which it cooperates with said chronograph counter (6) to place it in a predefined configuration, first and second control members (20, 58) arranged for controlling respectively said clutch device (8) and said brake (30) and said reset hammer ( 50) said reset hammer (50) being arranged in such a way that it is susceptible to be actuated independently of the respective positions of said transmission member (10) and said brake (30), forcing said brake (30) to leave its first position, and forcing said transmission member (10) to leave its engaged position, characterized in that said reset hammer (50) comprises a first neutralization portion (80) engageable with said transmission member (10) when said reset hammer (50) is actuated, a second neutralization portion (84) engageable with said brake (30) when said reset hammer (50) is actuated. 2. Chronograph mechanism according to claim 1, characterized in that said reset hammer (50) comprises an in-flight return arm (68) carrying said first and second neutralization portions (80, 84). Chronograph mechanism according to claim 2, characterized in that said reset hammer (50) is substantially plane, said first and second neutralization portions (80, 84) being provided on a slice of said return arm in flight. (68). 4. Chronograph mechanism according to claim 3, characterized in that said transmission member (10) and said brake (30) each carry a substantially cylindrical stud (86, 88) intended to cooperate with one of said neutralization portions ( 80, 84). 5. Chronograph mechanism according to one of claims 1 to 4, said reset hammer (50) having a rotational movement to move from one to the other of its first and second positions, characterized in that said first and second neutralization portions (80, 84) substantially have the shape of circular arcs centered on the axis of rotation of said reset hammer (50). Chronograph mechanism according to claim 5, characterized in that, in a plan view, said reset hammer (50) is intended to be arranged substantially in a first quarter of the watch movement (1), while said transmission member (10) and said brake (30) are intended to be arranged substantially in a second quarter of the watch movement (1), and in that said flight return arm (68) has a curved shape intended to circumvent the center of the watch movement (1). Chronograph mechanism according to claim 5 or 6, characterized in that said reset hammer (50) comprises a base (54) comprising a hole, defining its axis of rotation, and an actuating surface (56) arranged to cooperate with said second control member (58). ), and from which extend at least one first arm (64) carrying a reset surface (66) arranged to cooperate with said chronograph counter (6), and said flight return arm (68), the latter comprising, from said base (54) and towards its free end (74), a resting surface (76), a first inclined surface (78), said first portion neutralizer (80), a second inclined surface (82) and said second neutralization portion (84), and in that said flight return arm (68) is arranged in such a manner said resting surface (76) is arranged facing one of said transmission member (10) and said brake (30), and said first neutralization portion (80) is arranged facing the other one of said transmission member (10) and said brake (30) in said rest position of said reset hammer (50), and said first neutralization portion (80) is arranged facing one of said transmission member (10) and said brake (30), and said second neutralization portion (84) is arranged facing the other among said transmission member (10) and said brake (30), in said reset position of said reset hammer (50). 8. Chronograph mechanism (20) according to one of the preceding claims, characterized in that it comprises a counter chronograph minutes (36), said reset hammer (50) comprising an additional arm (60) bearing an additional reset surface (62) arranged to cooperate with said chronograph minute counter (36) to place it in a predefined configuration. 9. Watch movement (1) comprising a chronograph mechanism according to one of the preceding claims. Timepiece comprising a watch movement (1) according to claim 9.