Chronograph reset system

Abstract

The invention relates to a timepiece equipped with a system (1) for resetting a chronograph equipped with a chronograph counter gear, which includes at least one minute counter having a minute wheel (4), and a second counter, which includes a chronograph wheel (3). The system (1) includes a hammer (6) movable from an inactive position, where the hammer (6) is blocked by a locking means (11), to an active position, when the hammer (6) is released to contact the hearts (13, 14) of the wheels (3, 4) for resetting the chronograph. The system (1) includes a flexible element (10), such as an embedded spring, connected between a reset control means (12) and the hammer (6).The flexible element (10) is configured so as to store energy during a movement of the control means (12) and before the release of the hammer (6) by the locking means (11) so as to be able at the time of the release of the hammer (6) to restore this stored energy in order to drive the hammer (6) for the reset of the chronograph.

Description

Scope of the invention

[0001] The invention relates to a chronograph resetting system. The system is equipped with a chronograph counting mechanism, which includes at least one minute counter having a minute wheel, and a second counter, which includes a chronograph wheel. The system includes a hammer held in place by a locking means and movable from an inactive position, where the hammer is blocked by the locking means, to an active position, when the hammer is unblocked, for resetting the chronograph by contacting the various wheels. Background of the invention

[0002] Generally, a chronograph mechanism includes a chronograph counting train, which allows time to be counted from the second by means of a chronograph wheel or seconds counter, to the minute by means of a minute counter, and possibly to the hour by means of an hour counter. Each counter includes an indicator moving along a corresponding graduated scale. When resetting the chronograph, the indicator elements are traditionally indexed to an angular position corresponding to the zero of each graduated scale. For this purpose, each indicator element is generally mounted on the axis of a corresponding element of the train. The connection between the train element and its axis is frictional to allow these two elements independent angular movement beyond a certain torque. The indicator elements are indexed by means of corresponding heart and hammer mechanisms.The use of friction linkages and heart-and-hammer mechanisms means that the torque required when resetting the various counters can be significant, and a considerable amount of energy is consumed.

[0003] By way of comparison, in a traditional chronograph timepiece, a device known as a "buckling" mechanism is often used. Such a device creates a resistance point when a push-button is pressed, and once this resistance point is passed, the reset function is performed by inertia. It should be noted that the compressed spring, having passed the resistance point, experiences negative friction throughout its reset function, and a significant amount of energy is consumed.

[0004] Under these conditions, a way must be found to compensate for the energy consumed solely for resetting the various counters. An additional mainspring barrel could be used to provide the necessary energy, but space constraints arise in relation to the other basic components of the timepiece. It is therefore important to have alternative mechanisms for resetting the chronograph. Summary of the invention

[0005] The invention therefore aims to overcome the drawbacks of the prior art by providing a system for resetting a chronograph, particularly a timepiece. One objective of the invention is precisely to benefit from the accumulation of energy in a flexible element, such as an embedded spring, linked to a hammer, in order to release this energy when the hammer is released to reset the chronograph.

[0006] To this end, the invention relates to a chronograph reset system, which includes the features defined in independent claim 1.

[0007] Particular embodiments of the reset system are defined in dependent claims 2 to 14.

[0008] An advantage of the chronograph reset system according to the invention lies in the fact that it comprises a flexible element fixed at one end to the upper end of a hammer, and at the other end to a first portion of a control rocker mounted for rotation on a base, frame, or plate of the timepiece. During a chronograph reset operation, an external activating element, such as a push-button, is pressed on a second portion of the control rocker, causing the rocker to rotate about its axis of rotation, and thus driving the second end of the flexible element, such as an embedded spring, with a certain force so that it stores energy during this operation.

[0009] Another advantage of the chronograph reset system according to the invention lies in the fact that it includes a hammer locking means, preferably a hook-shaped element rotatably mounted on a base, frame, or plate of the timepiece. This element locks the hammer by means of a fixed pin mounted on the hammer when the hook at one end engages with the pin. Before pushing the second end of the hook-shaped element with one end of the second portion of the control lever, this end of the second portion of the control lever is initially positioned away from and opposite the second end of the hook-shaped element. Thus, when the push-button is pressed, pushing the second portion of the control lever, the flexible element is stressed and stores energy even before the second end of the hook-shaped element is pushed.This flexible element continues to store energy until the hook at the first end of the hooked mechanism is no longer in contact with the locking pin. After this point, the hammer is driven by the first end of the flexible element, which has stored enough energy to release and reset the chronograph.

[0010] Thus, the system allows energy to be stored via the flexible element to perform a chronograph reset function, and also allows a clean, frictionless triggering via the hook element when unlocking the hammer for the chronograph reset. Brief description of the drawings

[0011] The purposes, advantages and characteristics of the chronograph reset system will become clearer in the following description, particularly with regard to the drawings in which: <tb> <sep>Figures 1a and 1b represent a bottom view and a three-dimensional bottom view of the chronograph reset system before the chronograph reset operation according to the invention, <tb> <sep>Figure 2 shows a bottom view of the chronograph reset system just before the release of a hammer for the chronograph reset operation according to the invention. <tb> <sep>Figures 3a and 3b represent a bottom view and a three-dimensional bottom view of the chronograph reset system during the chronograph reset operation once the hammer is unlocked according to the invention, <tb> <sep>Figure 4 represents a three-dimensional view of a chronograph counting gear, mainly showing a minute counter gear of the reset system according to the invention, and <tb> <sep>Figure 5 represents a three-dimensional view of a chronograph counting gear, mainly showing a minute / hour counter gear of the reset system according to the invention. Detailed description of the invention

[0012] In the following description, elements of a chronograph reset system, which are well known in this technical field, will only be described summarily.

[0013] Figures 1a and 1b show a bottom view of the main components of a chronograph reset system 1 in a position prior to the reset operation. It normally also includes a chronograph counter gear 2 shown in more detail in Figures 4 and 5 described below. The reset system 1 can be mounted in a timepiece comprising a basic timekeeping movement and a chronograph movement, which can be self-contained with its own movement and therefore its own mainspring barrel. However, it can also be intended to use the basic movement of the timepiece with the chronograph.

[0014] The reset system 1 includes a chronograph hand 3, which is normally the seconds hand, forming part of the chronograph counter gear 2 shown in Figures 4 and 5. This chronograph counter gear includes, in particular, a minute counter, which includes a minute hand 4, and a second counter, which includes a chronograph hand 3. The chronograph counter gear may also include an hour counter, which includes an hour hand 5. The chronograph or seconds hand 3 has a cam-shaped core 13 mounted on the central axis 23 of the chronograph hand. The minute hand 4 has a cam-shaped core 14 mounted on the central axis 24. Finally, the hour module 5 has a cam-shaped core 15 mounted on the central axis 25.

[0015] It should be noted that a timepiece equipped with a chronograph usually includes chronograph components, which are mounted to pivot by friction on a frame or plate of the timepiece. This means that when resetting the chronograph, it is possible to rotate the components, held only by friction by their axis in an opening provided for this purpose, with sufficient torque until the chronograph reset indication is reached.

[0016] The reset system 1 mainly comprises a flexible element 10, which may be an embedded spring, connected between a reset control means 12 and an end portion of the hammer 6, which is used for resetting the chronograph. The flexible element 10 is configured to store energy during a movement of the control means 12 and before the release of the hammer 6, which is blocked by a locking means 11, so that, upon release of the hammer 6, it can release this stored energy and drive the hammer 6 to reset the chronograph.

[0017] Primarily, the flexible element 10 is connected by a first end 10a to the hammer 6, for example, to an end portion of the hammer 6 used for resetting the chronograph. A pin 19 is inserted into the first end 10a of the flexible element 10 and is housed in an elongated opening 9 made in a flat upper end of the hammer 6. The second end 10b of the flexible element 10 is attached to the control means 12, which is mounted on the base, frame, or plate of the timepiece, and is used during the chronograph reset operation. The flexible element 10, such as the integrated spring, is arched between its first end 10a and its second end 10b. This arched shape towards an external activation organ B, such as a push-button, which can act on the control means 12, can be adapted to improve the energy stored before the chronograph is reset.

[0018] The control means 12 is preferably a control rocker, for example a flat one, which is rotatably mounted by a fastening element 22, which is more likely a screw 22 passing through a central opening in the control rocker and which is screwed fixedly into a corresponding threaded hole in the base, frame, or plate of the timepiece. This control rocker 12, which is rotatably mounted about the axis defined by the screw 22, comprises a first portion on one side of the axis, to which the second end 10b of the flexible element 10 is fixed by studs 40 or other fastening means. The control rocker 12 further comprises a second portion on a second side of the rotation axis opposite the first side, and at one end of which a push-button B can be actuated to reset the chronograph. As explained later according to the invention, in a locked position, the hammer 6 is held locked by a locking means 11.Just before the chronograph is reset, the push-button B presses the second portion of the rotary control rocker 12 and, as a result, acts first on the flexible element from its second end 10b to carry out an accumulation of energy before the actual release of the hammer 6, which occurs by pressing the push-button B even further.

[0019] The hammer 6 is preferably a metal plate, and is mounted in translation with a first longitudinal opening 7 and a second longitudinal opening 8 in which are placed fixed rods 17, 18, which are for example a first screw 17 and a second screw 18. These two screws 17, 18 can be screwed into threads provided for this purpose on a base or frame or plate of the watch part not shown, but leaving the hammer free to move between an inactive blocking position and an active reset position. The two longitudinal openings 7, 8 are preferably of the same length and on the same line along the length of the hammer 6. The length of the longitudinal openings is adapted so that the hammer 6 can occupy an inactive blocking position and an active chronograph reset position in contact with the different hearts 13, 14 of the mobiles 3, 4 and also the heart 15 of the mobile 5 explained below.

[0020] The locking means 11 for the hammer 6 is preferably a hook member 11 rotatably mounted on the hammer 6. The flat-shaped hook member 11 comprises a central opening through which the second screw 18 passes. The screw 18 has a threaded hole in the second longitudinal opening 8 of the hammer 6, defined as the upper side of the hammer 6, where the push button B acts. The hook member 11 comprises, at a first end 11a, a hook for engaging a pin 26 fixed vertically on the hammer 6 near the second longitudinal opening 8 and between the two longitudinal openings 7 and 8 of the hammer 6. The second end 11b of the hook member 11, which is located on the opposite side with respect to the axis of rotation of the second screw 18, comprises a rod 21 by which a first free end of a return spring 31 of the hook member 11 can act to return the hook organ 11 in a hammer 6 locking position.A second end of the return spring 31 can be fixed by a screw 51 screwed into a corresponding threaded hole made in the base or the frame or the plate of the timepiece.

[0021] For a chronograph reset operation, an inner end 12' of the second portion of the rotating control rocker 12 is positioned opposite and away from the second end 11b of the hook member 11. When the push-button B is pressed for a chronograph reset operation, the flexible element 10 first stores energy by the rotation of the control rocker 12 following the pressing of the push-button B. The flexible element 10 stores energy even before the inner end 12' of the second portion of the control rocker 12 pushes the second end 11b of the hook member 11, and this continues until the hook of the first end 11a of the hook member 11 no longer catches the pin 26 of the hammer 6, which allows for a clean triggering without additional friction.In this state, the hammer 6 is no longer in a locked position and can more easily reset the chronograph thanks firstly to the release of energy stored by the flexible element 10 and subsequently by the pressure of the push-button B by a user.

[0022] Thanks to the energy accumulated by the flexible element 10 just before the hammer 6 is released, the chronograph reset operation is facilitated. The hammer 6 is pushed by the flexible element 10 from its first end 10a towards the various moving parts 3, 4, 5, particularly the moving parts 13, 14, 15. To achieve this, and in the case of the three available moving parts, the hammer 6 comprises three contact portions 16a, 16b, 16c. A first contact portion 16a, located on the hammer 6, makes contact with the heart 13 of the chronograph movement 3. A second contact portion 16b, also located on the hammer 6, makes contact with the heart 15 of the hour movement 5. The first contact portion 16a and the second contact portion 16b form an assembly mounted for rotation around an axis 37 on the hammer 6 near the first longitudinal opening 17. An angular stop 36 is provided between the first contact portion 16a and the second contact portion 16b.This stop 36 passes with some play in a central opening of the assembly, which allows for compensation of geometric defects in the components. Finally, a third contact portion 16c, located on the hammer 6 near the first end 10a of the flexible element 10, comes into contact with the core 14 of the minute wheel 4. This third contact portion 16c is connected by a U-shaped metal band, and its end opposite the contact portion is fixed by studs 43 or other fastening means to the upper end of the hammer 6. An adjusting eccentric 44 is fixed in a corresponding hole in the upper end of the hammer 6 to adjust the position of the third contact portion 16c.

[0023] The position of these three moving parts 3, 4, 5 and of the contact portions 16a, 16b, 16c at the end of the chronograph reset are explicitly shown in Figures 3a and 3b, which will not be described in further detail as they include the same elements described above in Figures 1a and 1b. Each plate of the hearts 13, 14, 15 is held in a zero position by each respective contact portion 16a, 16b, 16c. The screws or other rods 17 and 18, which are in each longitudinal opening 7 and 8, are at one upper end of the longitudinal openings 7 and 8 during the reset and before being placed in an inactive hammer-locking position 6 once the push-button B is released. The length of each longitudinal opening 7 and 8 is determined in such a way that each screw 17 and 18 can move from an inactive position when the hammer 6 is locked and an active reset position.

[0024] By way of illustration only, a minute hand 34 must be friction-connected to the shaft 24 to indicate the chronograph minutes on a dial not shown on the timepiece. An hour hand 35 must be friction-connected to the shaft 25 to indicate the chronograph hours on the dial not shown on the timepiece. The same may apply to the chronograph seconds indication, but no hand is shown.

[0025] In order to return the flexible element 10 to its initial position once the push-button B is released, another return spring 32 may be provided, one free end 32a of which contacts a housing 41 formed in the first portion of the rotating control rocker 12 under the second end 10b of the flexible element 10. The other end 32b of the return spring 32 is fixed by means of a screw 42, which is screwed into a corresponding threaded hole in the base, frame, or plate of the timepiece. Once the flexible element 10 and the push-button B are in their initial positions, the return spring 31 pushes the hook-shaped member 11 into its hammer-locking position in a conventional manner before the next chronograph reset operation.

[0026] Figure 2, which shows only the bottom view of the chronograph reset system, merely illustrates the energy stored by the flexible element 10 just before the hammer 6 is released when the hook at the first end 11a of the hook member 11 frees it from its locking position. By rotating the control lever 12, the second end 10b of the flexible element 10a tends to rotate clockwise, straightening the flexible element 10 and thus storing energy to be released when resetting the chronograph. Of course, all the other components in Figure 2 will not be repeated, as they have already been explained with reference to Figures 1a and 1b.

[0027] Figures 4 and 5 below represent a chronograph counting mechanism 2, which comprises, on the one hand, a minute mechanism in Figure 4 and, on the other hand, an hour mechanism in Figure 5. The various wheels for the minute and hour mechanisms are shown connected by dashed lines. In the case primarily of the minute mechanism, which is shown in Figure 4, a first toothed wheel 62, located on the axis 23 of the chronograph wheel 3, meshes with an intermediate wheel 63, the diameter of which is larger than the diameter of the first toothed wheel 62. A second intermediate wheel 64, of smaller diameter, is placed on the intermediate wheel 63 to drive a wheel of the hour mechanism, as explained below. A third proximal intermediate wheel 65 coaxial and of smaller diameter than the intermediate wheel 63 allows to drive a large wheel 66 mounted on the axis 24 of the minute wheel 4.The size of each wheel is of course determined according to the time counted and to be displayed to move from the second with a first indicator organ to the minute with a second indicator organ, such as a 34-point hand on a dial not shown.

[0028] Figure 5 mainly represents the hour gear train. The first toothed wheel 62, located on the axis 23 of the chronograph wheel 3, meshes with the intermediate wheel 63, whose diameter is larger than the diameter of the first toothed wheel 62. The second intermediate wheel 64, with a smaller diameter, meshes with a second intermediate wheel 68, with a larger diameter, which itself includes below it another small intermediate wheel intended to drive another large wheel 67. A proximal wheel of a smaller diameter on the same axis drives an hour wheel 69. The size of each wheel is, of course, determined according to the time to be counted and displayed to move from the second, indicated by a first indicator, to the hour, indicated by a third indicator, such as a hand 35 on a dial not shown.

[0029] As can be seen in Figures 4 and 5, the minute hand 34 and the hour hand 35 are not directly connected to their respective axes of the wheels 4 and 5. The center points 14 and 15 of the minute wheels and the hour wheels 4 and 5 are each located under wheels 66 and 69. Both the minute and hour gear trains are well known in this technical field of chronograph timepieces. No further details will be explained in more detail.

[0030] Based on the above description, multiple embodiments of the reset system for resetting a chronograph can be designed by a person skilled in the art without departing from the scope of the invention as defined by the claims. One or more flexible elements of identical or different shapes may be provided, arranged between one end of the hammer and the control lever. Furthermore, it may be envisaged to have one or more rotating hammers, rather than hammers with linear motion, for resetting the chronograph.< / sep> < / tb> < / sep> < / tb> < / sep> < / tb> < / sep> < / tb> < / sep> < / tb>

Claims

1. A chronograph reset system (1) which is equipped with a chronograph counting gear (2), which includes at least one minute counter having a minute wheel (4), and a second counter, which includes a chrono wheel (3), the minute wheel (4) having a heart (14), constituting a cam shape, mounted on a central axis (24) of the minute wheel and the chrono wheel (3) having a heart (13) mounted on a central axis (23) of the chrono wheel, the system (1) including a hammer (6) held locked by a locking means (11) and movable from an inactive position, where the hammer (6) is locked by the locking means (11), and an active position, when the hammer (6) is unlocked, for resetting the chronograph in contact with the different hearts of the wheels (3, 4),characterized in that the system (1) comprises a flexible element (10) connected between a reset control means (12) and the hammer (6) used for resetting the chronograph, and is configured such that it stores energy during a movement of the control means (12) before the hammer (6) is released by the locking means (11) so that, at the moment of release of the hammer (6), it is able to release this stored energy and drive the hammer (6) to reset the chronograph.

2. System (1) according to claim 1, characterized in that the flexible element (10) is linked by a first end (10a) to the hammer (6), which is used for resetting the chronograph, and in that a second end (10b) of the flexible element (10) is fixed to the control means (12) which is mounted on a base or frame or plate of a timepiece.

3. System (1) according to claim 2, characterized in that the first end (10a) of the flexible element (10) is connected by means of a rod or pin (19) inserted into an elongated opening (9) made at a flat upper end of the hammer (6).

4. System (1) according to claim 2, characterized in that the flexible element is arcuate in shape between its first end (10a) and its second end (10b), this arcuate shape being in the direction of an external activation member (B) of the control means (12).

5. System (1) according to any one of claims 1 to 4, characterized in that the control means (12) is a control rocker (12), which is rotatably mounted by a fixing element (22) passing through a central opening of the control rocker (12) and which is fixed in the base or the frame or the plate of the timepiece.

6. System (1) according to claim 5, characterized in that the flat-shaped control rocker (12) is rotatably mounted by a screw (22) passing through the central opening of the control rocker (12) and which is screwed fixedly into a corresponding thread in the base or the frame or the plate of the timepiece.

7. System (1) according to claim 6, characterized in that the control rocker (12) comprises a first portion on a first side of the axis (22) on which is fixed by fastening means (40), such as studs (40), the second end (10b) of the flexible element (10), and in that the control rocker (12) comprises a second portion on a second side of the axis opposite to the first side, and at one end of which the external activation member, which is a push button (B), can act.

8. System (1) according to claim 1, characterized in that the hammer (6) is mounted in translation with a first longitudinal opening (7) and a second longitudinal opening (8) in which fixed rods are placed, which are for example a first screw (17) in the first longitudinal opening (7) of the hammer (6) and a second screw (18) in the second longitudinal opening (8) of the hammer (6), the hammer moving in a rectilinear manner from the inactive position to the active reset position, the two screws (17, 18) being screwed into threads provided for this purpose on a base or frame or plate of the timepiece.

9. System (1) according to claim 8, characterized in that the locking means (11) comprises a hook member (11) rotatably mounted on the hammer (6), the second screw (18) for guiding the hammer (6) passing through a central opening in the hook member (11) and from the upper side of the hammer (6) towards the control means (12), in that the hook member (11) comprises a first end (11a) with a hook for engaging a pin (26) fixed vertically on the hammer (6) near the second longitudinal opening (8) and between the two longitudinal openings (7, 8), and in that the hook member (11) comprises a second end (11b) on a side opposite the first end with respect to the axis of rotation (18), a rod (21) being mounted through the second end (11b) and being arranged to be pushed by a portion of the control means (12) into a reset operation.

10. System (1) according to claim 9, characterized in that the control means (12) is a control rocker (12) rotatably mounted by a screw (22) passing through the central opening of the control rocker (12) and which is screwed fixedly into a corresponding thread in the base or the frame or the plate of the timepiece, in that the control rocker comprises a first portion on a first side of the axis (22) for fixing the second end (10b) of the flexible element (10), in that the control rocker (12) comprises a second portion on a second side of the axis opposite to the first side,and at one end of which a push button (B) can act, and in that an inner end (12') of the second portion of the control rocker (12) is arranged opposite and distant from the second end of the hook member (11) in such a way as to allow the flexible element to store energy when the push button is pressed before the rod (21) of the second end (11b) of the hook member (11) is pushed by the inner end (12') of the second portion of the rocker, and until the moment when the hook of the first end (11a) is no longer hooked to the pin (26) of the hammer (6) to release the stored energy to drive the hammer (6) in resetting the chronograph.

11. System (1) according to claim 10, the chronograph further comprising an hour counter equipped with an hour wheel (5), a core of the hour wheel being mounted on a central axis of the hour wheel, characterized in that the unlocked hammer (6) is pushed by the flexible element (10) from its first end (10a) and in the direction of the various cores (13, 14, 15) of the wheels (3, 4, 5), in that the hammer (6) comprises three contact portions (16a, 16b, 16c), a first contact portion (16a) disposed on the hammer (6) coming into contact with the core (13) of the chronograph wheel (3), a second contact portion (16b) disposed on the hammer (6) coming into contact with the core (15) of the hour wheel (5), and a third contact portion (16c) disposed on the hammer (6) near the first end (10a) of the flexible element (10) coming into contact with the heart (14) of the mobile of the minutes (4).

12. System (1) according to claim 11, characterized in that the first contact portion (16a) and the second contact portion (16b) form an assembly mounted rotatably about an axis (37) on the hammer (6) near the first longitudinal opening (17), and in that an angular stop (36) is disposed between the first contact portion (16a) and the second contact portion (16b) by passing through a central opening of the assembly with a certain clearance.

13. System (1) according to claim 11, characterized in that the third contact portion (16c) is connected by a U-shaped metal band and its end opposite the contact portion (16c) is fixed by studs (43) to the upper end of the hammer (6).

14. System (1) according to claim 13, characterized in that an adjusting eccentric (44) is fixed in a hole corresponding to the upper end of the hammer (6) to adjust the position of the third contact portion (16c).