CH715969B1 - Mechanism for generating a frictional force. - Google Patents

Abstract

The invention relates to a horological mechanism (10) for generating a friction force comprising: an inverter (100), having a first surface and a second surface, and moving from a first to a second position, a reference (500) in contact with the first surface, an elastic piece (300) in contact with the second surface and exerting the frictional force on the reverser, means (400) for fixing the elastic piece to the reference piece. The watch mechanism is arranged so that the frictional force F satisfies the rotation: m g ≤ F ≤ 2m g m denoting the mass of the inverter, so as to create a rotational torque to move the inverter by the first to the second position when the reverser is actuated by an oscillating weight. The watch mechanism thus generates a friction force that is controllable and reliable over time.

Description

Technical area

The present invention relates to a watch mechanism for generating a friction force for a mechanical movement, in particular for a mechanical movement comprising an oscillating weight.

State of the art

[0002] Oscillating weights for automatic watches are well known and widely used. Typically, an oscillating mass makes it possible to ensure the winding of a movement thanks to its oscillations generated by the movements of the wearer of the watch. The mass is pivotally mounted for example by means of a bearing. As a general rule, an inverter (or walkman) ensures the transformation of the alternating movement of the mass into a one-way rotary movement. The gear trains of the winding system ensure the connection between the various elements. The rotational drive of the winding train makes it possible to arm a source of energy of the watch, for example the spring of a barrel.

[0003] Watches are known in which the oscillating weight is arranged at the bottom of the case, for example mounted on the bridge side of the watch. Watches are also known in which the oscillating weight is arranged in correspondence of the dial of the watch.

[0004] Oscillating weights are known which are not visible to the wearer of the watch. However, automatic watches are also known provided with an oscillating weight visible by the wearer on the back or front face of the watch.

[0005] Oscillating masses are known which are arranged to oscillate around the center of the watch movement. Smaller oscillating weights are also known, which are arranged to oscillate around a point of the watch movement different from its center. These oscillating masses are commonly referred to as "micro-rotors".

[0006] The reverser is arranged to move from a first position to a second position (and vice versa) when it is actuated by the oscillating mass. In other words, if the oscillating mass rotates in a first direction of rotation, the reverser occupies a first position in which it enables the source of energy of the movement to be armed, for example by meshing directly with the source of energy. When the oscillating mass rotates in a second direction of rotation opposite to the first direction of rotation, the reverser is arranged to move into a second position, in which it still allows the energy source of the movement to be armed, for example by meshing with the energy source via a mobile which allows the reversal of the direction of rotation of the movement given by the oscillating mass via the inverter. In this way, the inverter ensures the transformation of the reciprocating movement of the mass into a one-way rotary movement.

[0007] When changing the direction of rotation of the oscillating mass, the gearing of the slider is not always done correctly.

[0008] In order to improve the meshing of the reverser when changing the direction of rotation of the oscillating mass, it is known to use grease, so as to create a torque to move the reverser from the first position described above to the second position described above (and vice versa) when the reverser is actuated by the oscillating weight.

[0009] The use of grease involves various disadvantages: firstly, it is difficult to dose and consequently the resulting friction force is difficult to control. Second, it is unreliable over time.

[0010]There is therefore a need to correct the lack of meshing of the player when changing the direction of rotation of the oscillating weight in a controllable and/or reliable manner over time.

Brief summary of the invention

[0011] An object of the present invention is therefore to correct the lack of meshing of the slider when changing the direction of rotation of the oscillating weight in a controllable and/or reliable manner over time.

According to the invention, these objects are achieved in particular by means of a watchmaking mechanism for generating a friction force according to claim 1.

The watch mechanism for generating a friction force for a mechanical movement comprising an oscillating mass according to the invention comprises: an inverter, having a first surface and a second surface opposite the first surface and being arranged to move from a first position to a second position, an elastic part, arranged to exert the frictional force on the reverser by pressing (directly or indirectly, for example via another part) on its second surface, a reference part arranged to come into contact (directly or indirectly, for example via another part) with the first surface of the inverter, fixing means, for fixing the elastic part to the reference part.

According to the invention, the friction force is substantially perpendicular to the first surface and to the second surface, so as to pinch the reverser between the elastic part and the reference part.

According to the invention, the watch mechanism is arranged so that the friction force F satisfies the following relationship: m g ≤ F ≤ 2m g in which m denotes the mass of the reverser and g denotes the acceleration of gravity, so as to create a rotational torque to move the reverser from the first position to the second position when the reverser is actuated by the oscillating weight .

[0016] This solution has the particular advantage over the prior art of doing away with the use of grease, which is unreliable over time and difficult to dose. Thanks to the watch mechanism according to the invention, it is thus possible to correct the lack of meshing of the slider when changing the direction of rotation of the oscillating mass by generating a controllable and reliable friction force over time, to create a torque of rotation to move an inverter from a first position to a second position.

[0017] In one embodiment, the mechanism comprises a force distribution plate between the elastic part and the reverser, in order to distribute the frictional force generated on each zone or part of the reverser.

[0018] In one embodiment, the elastic part is arranged to come into contact with the distribution plate in correspondence of at least two bearing points or bearing zones.

[0019] In one embodiment, the distribution plate comprises a through opening to limit the displacement of the inverter between the first position and the second position.

In one embodiment, the two support points are in correspondence of two opposite edges defining the through opening of the distribution plate.

In one embodiment, the reference part comprises two cavities, the distribution plate comprises two elongated ends cooperating with these cavities, in order to guarantee correct positioning of the plate in the reference part.

[0022] In another embodiment, the elastic part comprises at least part of the plate of the mechanical movement.

[0023] In another embodiment, the reference part comprises at least part of a bridge of the mechanical movement.

In another embodiment, the elastic part is a first elastic part, the reference part comprising a second elastic part or a portion of the first elastic part.

In another embodiment, the distribution plate is a first distribution plate, the reference part comprising a second distribution plate or a portion of the first distribution plate.

In another embodiment, the watch mechanism comprising a mechanical reaction system making it possible to reduce the frictional force when the reverser is in the first position or in the second position.

The invention also relates to a mechanical movement comprising: the watch mechanism according to the invention, and the oscillating weight.

[0028] In another embodiment, the mechanical movement comprises a cavity to house the timepiece mechanism.

In another embodiment, the cavity has a depth substantially equal to the thickness of the timepiece mechanism in order to minimize the total thickness of the mechanical movement comprising the timepiece mechanism.

The invention also relates to a watch comprising the timepiece mechanism according to the invention or the mechanical movement according to the invention.

Brief description of figures

Examples of implementation of the invention are indicated in the description illustrated by the appended figures in which:

[0032] Figure 1 illustrates a perspective view of an embodiment of a mechanical movement comprising an embodiment of the timepiece mechanism according to the invention, in which the timepiece mechanism is shown exploded.

[0033] Figure 2 illustrates a perspective view of the embodiment of the mechanical movement of Figure 1, in which the timepiece mechanism is also shown in perspective and mounted in the mechanical movement.

Figure 3 is a detail of Figure 1, in particular it illustrates an exploded view of an embodiment of the timepiece mechanism according to the invention.

[0035] Figure 4 illustrates a bottom view (dial side) of the embodiment of the mechanical movement of Figure 1.

[0036] Figure 5 illustrates a top view (bottom side) of the embodiment of the mechanical movement of Figure 1.

[0037] Figure 6 illustrates a top view of part of the mechanical movement of Figure 1.

[0038] Figure 7 illustrates a bottom view of the part of the mechanical movement of Figure 6.

[0039] Figure 8 illustrates a side view with the bottom side of the part of the mechanical movement of Figures 6 and 7.

[0040] Figure 9A illustrates a sectional view of an embodiment of the mechanical movement according to the invention, in which the reverser is driven by the barrel ratchet via a first mobile, a second mobile and also via a mobile intermediate.

[0041] Figure 9B illustrates a sectional view of another embodiment of the mechanical movement according to the invention, in which the reverser is driven by the barrel ratchet via a first mobile and a second mobile.

[0042] FIG. 10A illustrates a bottom view of part of the mechanical movement according to another embodiment of the invention, in which the inverter occupies a first position.

[0043] Figure 10B illustrates a bottom view of the part of the mechanical movement of Figure 10A, in which the inverter occupies a second position.

[0044] Figure 11 illustrates a sectional view of another embodiment of the timepiece mechanism according to the invention.

[0045] Figure 12 illustrates a sectional and schematic view of another embodiment of the timepiece mechanism according to the invention.

Example(s) of embodiment(s) of the invention

[0046] Figure 1 illustrates a perspective view of an example of mechanical movement 1 comprising an embodiment of the timepiece mechanism 10 according to the invention, shown in an exploded view.

The mechanical movement according to the invention 1 advantageously comprises an oscillating weight 4 (visible for example in Figure 5). This oscillating weight 4 is arranged to be able to rotate freely in both clockwise and counterclockwise directions of rotation, according to the movements of its wearer.

In a preferred variant, the oscillating mass 4 is a micro-rotor. The mechanism according to the invention is indeed particularly advantageous when it cooperates with micro-rotors.

The mechanical movement 1 advantageously comprises a power source. In the illustrated embodiment, this energy source comprises a barrel, whose ratchet 2 is visible in Figure 1.

In the example of Figure 1, the watch mechanism 10 includes an inverter 100. This inverter 100 is arranged to move from a first position (visible for example in Figure 10A) to a second position (visible by example in FIG. 10B), in order to transform the reciprocating movement of the oscillating mass 4 into a one-way rotary movement.

As best seen in Figure 3, which is a detail of Figure 1 and illustrates in particular an exploded view of the watch mechanism 10 of Figure 1, the inverter 100 comprises two main surfaces, namely a first surface S1 intended to cooperate with a reference part such as for example the plate of movement 1, as will be seen, and a second surface S2 intended to cooperate (via a distribution plate 200 in the example of FIG. 3) with a part elastic 300 of the watch mechanism 10. The first surface S1 is substantially parallel to the second surface S2.

The reverser 100 also comprises a toothing 101, intended to mesh both with the pinion 40 of the oscillating weight 4 and with a mobile 7, visible for example in Figures 10A and 10B.

This toothing 101 also allows the inverter 100 to cooperate both with a first mobile (when the inverter 100 is in its first position) and with a second mobile (when the inverter 100 is in its second position ), so as to transform the reciprocating movement of the oscillating weight 4 into a one-way rotary movement.

[0054] For example and without limitation, in the example of Figure 10A the inverter 100 cooperates both with the pinion 40 of the oscillating weight 4 and with the winding ratchet 2 when it occupies its first position .

For example and without limitation, in the example of Figure 10B the inverter 100 cooperates both with the pinion 40 of the oscillating mass 4 and with an intermediate mobile 7 when it occupies its second position.

Obviously, the examples of Figures 10A and 10B are not limiting. For example, it is possible to define an embodiment in which the inverter 100 does not mesh directly with the winding ratchet 2 when it is in its first position, but via other intermediate mobiles. Furthermore, reduction mobiles can also be provided between the oscillating weight 4 and the winding ratchet 2, in order to reduce the initial speed of the oscillating weight 4 and to increase the force intended for winding the barrel spring.

As discussed, the timepiece mechanism 10 of Figure 3 also comprises an elastic part 300 arranged to exert on the inverter 100 a frictional force by pressing on the second surface S2 of the inverter 100. In the example of Figure 1, the support of the elastic part 300 on the inverter 100 is not direct, but is done via a distribution plate 200 between the elastic part 300 and the inverter 100. This plate 200 makes it possible to distribute on the reverser 100 the force exerted by the elastic part 300.

However, the presence of the distribution plate 200 is optional. For example, the watch mechanism 10 of the embodiment of FIG. 10, which will be discussed later, may be devoid of any distribution plate 200: in this example, the support of the elastic part 300 on the inverter 100 is direct, that is to say the elastic part 300 touches the reverser 100 directly, in particular its second surface S2.

In the example illustrated in Figure 3, the elastic part 300 is a spring comprising two blades 301 and 303 whose free ends 3010 respectively 3030 are substantially parallel. These two ends 3010 and 3030 are arranged to come into contact with the distribution plate 200, in correspondence of at least two points or support zones 201 respectively 203.

In the example illustrated in Figure 3, the elastic piece 300 also comprises a through hole 304 which cooperates with a fixing means (a screw 400 in the example illustrated), in order to fix the elastic piece 300 to a reference part (for example to the plate 500 of the movement, visible for example in Figure 1), so as to pinch the inverter 100 between the elastic part 300 and the reference part. Any other fixing means can also be used to fix the elastic part 300 to the reference part.

In the example illustrated in Figure 3, the distribution plate 200 comprises a through opening 202. This opening 202 is intended to cooperate with the axis 102 of the inverter 100, so as to limit the movement of the inverter 100 between the first position and the second position. In particular, when the inverter 100 is in its first position, the axis 102 is against the first end 2021 of the through opening. When the inverter 100 moves from the first position to the second position, the axis 102 moves in the through opening 202 until it comes against the second end 2022 of the through opening 202 when the inverter 100 is in the second position.

In the example of Figure 3, the through opening 202 has an elongated shape, the longer sides of which are defined by edges 201 respectively 203. In a preferred variant, the ends 3010, 3030 of the elastic blades 301 , 303 press directly on these edges 201 respectively 203, so as to distribute more effectively the force exerted by the elastic part 300 on the reverser 100.

In the embodiment of Figure 3, the distribution plate 200 comprises two elongated ends 205, cooperating with corresponding cavities in the plate 500 (not shown), to ensure proper positioning of the distribution plate 200 in the 500 plate.

The friction force F generated by the mechanism according to the invention is substantially perpendicular to the first surface S1 and to the second surface S2, and the watch mechanism is arranged so that the friction force F satisfies the relationship next : m g ≤ F ≤ 2m g in which m designates the mass of the inverter 100 and g designates the acceleration of gravity, so as to create a rotation torque to move the inverter 100 from the first position to the second position when said inverter is actuated by the mass oscillating 4.

The friction force F generated by the watch mechanism 10 according to the invention is reliable over time. In addition, it can be controlled, for example by acting on the modulus of elasticity (Young's modulus) of the elastic part 300; on the ground of the inverter 100; on the choice of materials for the inverter 100, the reference part 500, the distribution plate 200 and/or the elastic part 300; on the force exerted by the fixing means 400; and/or on the shape and dimensions of the inverter 100, of the reference part 500, of the distribution plate 200 and/or of the elastic part 300; etc

[0066] Figure 2 illustrates a perspective view of the embodiment of the mechanical movement of Figure 1, in which the watch mechanism 10 is also shown in perspective and mounted in the mechanical movement 1. In particular, the watch mechanism 10 is placed inside a cavity 50 arranged in the plate 500.

In one embodiment, the cavity 50 has a depth substantially equal to the thickness of the watch mechanism 10 in order to minimize the total thickness of the mechanical movement 1 comprising the watch mechanism 10.

[0068] Figure 4 illustrates a bottom view of the embodiment of the mechanical movement of Figure 1, in which it is possible to see the cavity 50 arranged in the plate 500 and receiving the watch mechanism 10.

[0069] Figure 5 illustrates a top view of the embodiment of the mechanical movement of Figure 1. In this example, the oscillating mass 4 has a center of rotation which does not correspond to the center of the mechanical movement 1. In the example of Figure 5, the ratchet 2 cooperates with a first mobile 5, which in turn cooperates with a second mobile 6.

[0070] Figure 6 illustrates a top view of part of the mechanical movement of Figure 1. Figure 7 illustrates a bottom view of the part of the mechanical movement of Figure 5. Figure 8 illustrates a sectional view part of the mechanical movement of figures 6 and 7.

In the embodiment of Figures 6 to 8, the inverter 100 cooperates both with the pinion 40 of the oscillating weight 4 and with the mobile 6. In the embodiment of Figures 6 to 8, a pawl 3 serves as a non-return to the ratchet 2, in order to prevent it from discharging. This is a leaf spring which gets stuck in a tooth of ratchet 2 and presses in the plate (not shown). This forces ratchet 2 to only turn one way. This also applies to pawl 8 which acts on mobile 6.

[0072] FIG. 9A illustrates a sectional view of an embodiment of the mechanical movement 1 according to the invention, in which the reverser 100 is driven by the barrel ratchet 2 via a first wheel set 5, a second wheel set 6 , passing through an intermediate mobile 7.

[0073] Figure 9B illustrates a sectional view of another embodiment of the mechanical movement 1 according to the invention, in which the reverser 100 is driven by the barrel ratchet 2 via a first mobile 5 and a second mobile 6.

In the examples of Figures 1 to 10B, the reference part of the watch movement 100 is the plate 500, or at least part of the plate 500, of the mechanical movement 1.

In another example (not illustrated), the reference part of the watch movement 100 is a bridge, or at least part of a bridge, of the mechanical movement 1.

[0076] Figure 11 illustrates a sectional view of another embodiment of the timepiece mechanism 10 according to the invention. The elastic part 300 in this example is a leaf spring which comes into contact with both the first surface S1 and the second surface S2 of the inverter 100, sandwiching it.

[0077] The elastic part of Figure 11 comprises a first portion 310, substantially parallel to the first surface 51 of the inverter 100, a second portion 320, substantially parallel to the second surface S2 of the inverter 100 and a third portion 340, connecting the first portion 310 to the second portion 320. In this example, the third portion 340 is substantially perpendicular to the first surface S1 and to the second surface S2. In other examples the third portion 340 can have a curved shape.

In the example illustrated the elastic piece 300 is a one-piece piece. In other examples, the different portions 310, 320, 340 are separate parts, interconnected by connection means, in a removable or non-removable manner.

The second portion 320 of the elastic part 300 comes into contact with the second surface 52 of the reverser 100: therefore it not only makes it possible to exert a force on the reverser like an elastic part, but also to distribute this force on the inverter 100 as a distribution plate.

The first portion 310 of the elastic part 300 comes into contact with the first surface S1 of the inverter 100: therefore it also makes it possible to act as a first reference part, which is connected to a second reference part ( a 500 plate for example) via a 400 screw.

The third portion 340 connects the first portion 310 to the second portion 320 and acts as a fixing means, to fix the elastic part (the second portion 320) to the reference part (the whole of the first portion 310 and of the 500 plate).

[0082] FIG. 11 illustrates a sectional and schematic view of another embodiment of the timepiece mechanism 10 according to the invention. In this example, the reverser 100 cooperates in correspondence of its second surface S2 with an elastic part 300" (schematically illustrated by a helical spring) via a distribution plate 200". The elastic piece 300" is fixed to a reference piece 500 (schematically illustrated by a ground) via connection means 400" (schematically illustrated by a line).

In this example, the reverser 100 cooperates in correspondence of its first surface S1 also with another elastic part 300' (schematically illustrated by another helical spring) via another distribution plate 200'. The elastic part 300' is fixed to the reference part 500 via other connection means 400' (schematically illustrated by a line).

In the illustrated variant, the inverter 100 comprises two axes 102' and 102", to cooperate with corresponding through openings (not shown) of the distribution plates 200' respectively 200".

In another variant, the inverter 100 comprises a single axis (102' or 102'').

[0086] In a variant (not shown), the timepiece mechanism 10 of FIG. 12 does not have a distribution plate (200' or 200").

[0087] In another variant, the two distribution plates 200′, 200″ are interconnected, thus forming a single piece (monobloc or comprising different parts interconnected, removably or non-removably).

In another embodiment (not illustrated), the watch mechanism according to the invention also comprises a mechanical reaction system making it possible to reduce the friction force F when the inverter 100 is in the first position or in the second place.

For example, this mechanical reaction system may comprise a cam cooperating with the mechanism 10 according to the invention and having a shape arranged to reduce the frictional force when the reverser 100 is in the first position or in the second position. position.

For example, this mechanical reaction system comprises an elastic part having a shape arranged to reduce the frictional force when the reverser 100 is in the first position or in the second position.

[0091] For example, this mechanical reaction system comprises an inverter having a variable thickness and arranged to reduce the frictional force when the inverter 100 is in the first position or in the second position.

The invention also relates to a mechanical movement comprising the watch mechanism 10 according to the invention, and the oscillating weight 4.

The invention also relates to a watch comprising the timepiece mechanism according to the invention or the mechanical movement according to the invention.

Reference signs used in the figures

[0094] 1 Mechanical movement 2 Winding ratchet 3 Pawl 4 Oscillating mass 5 First mobile 6 Second mobile 7 Intermediate mobile 8 Pawl 10 Watchmaking mechanism for generating a friction force 40 Pinion of the oscillating mass 50 Cavity of the plate 100 Inverter 101 Inverter gear 102 Inverter shaft 200 Force distribution plate 201 First edge of through opening 202 Second edge of through opening 202 Through opening 2021 First end of through opening 2022 Second end of through opening 205 Extended end 300 Elastic piece 301 First elastic blade 303 Second elastic blade 310 First portion of the elastic piece 320 Second portion of the elastic piece 340 Third portion of the elastic piece 3010 End of the first elastic blade 3030 End of the second elastic blade 304 Hole 400 Means of connection 500 Reference part (plate) S1 First surface S2 Deu xth surface

Claims (14)

1. Clockwork mechanism (10) for generating a friction force for a mechanical movement (1) comprising an oscillating mass (4), said clockwork mechanism (10) comprising: – an inverter (100), having a first surface (S1) and a second surface (S2) opposite said first surface, said inverter (100) being arranged to move from a first position to a second position, – a reference piece (500), arranged to come into contact with the first surface (S1) of said inverter (100), – an elastic part (300) arranged to exert on said reverser (100) said frictional force by pressing on the second surface (S2) of said reverser (100), – fixing means (400), for fixing the elastic part (300) to the reference part (500), so as to pinch said inverter (100) between the elastic part (300) and the reference part (500) , said frictional force being substantially perpendicular to said first and second surfaces (S1, S2), said watch mechanism (10) being arranged so that said frictional force F satisfies the following relationship: m g ≤ F ≤ 2m g wherein m denotes the mass of said inverter (100) and g denotes the acceleration of gravity, so as to create a rotational torque to move said inverter (100) from the first position to the second position when said inverter (100) is actuated by the oscillating weight (4). 2. Timepiece mechanism (10) according to claim 1, comprising a distribution plate (200) of the force between said elastic part (300) and said inverter (100). 3. Timepiece mechanism (10) according to claim 2, in which the elastic piece (300) is arranged to come into contact with the distribution plate (200) in correspondence of at least two support points or support zones. . 4. Clockwork mechanism (10) according to one of claims 2 and 3, wherein the distribution plate (200) comprises a through opening (202) to limit the movement of said inverter (100) between the first position and the second position . 5. Timepiece mechanism (10) according to claims 3 and 4, wherein the two support points are in correspondence of the two opposite edges (201, 203) defining said through opening (202). 6. Timepiece mechanism (10) according to one of claims 2 to 5, the reference part (500) comprising two cavities, the distribution plate (200) comprising two elongated ends (205) cooperating with said cavities, in order to guarantee correct positioning of the distribution plate (200) in the reference part (500). 7. Timepiece mechanism (10) according to one of claims 1 to 6, the elastic part being a first elastic part, the reference part comprising a second elastic part or a portion of the first elastic part, the second elastic part being separate and connected to the first elastic piece. 8. Timepiece mechanism (10) according to one of claims 2 to 6, the distribution plate being a first distribution plate, the reference part comprising a second distribution plate or a portion of the first distribution plate, the second distribution plate being separate and connected to the first distribution plate. 9. Timepiece mechanism (10) according to one of claims 1 to 8, comprising a mechanical reaction system making it possible to reduce the frictional force when said reverser (100) is in the first position or in the second position. 10. Mechanical movement (1) comprising: – the timepiece mechanism (10) according to one of claims 1 to 9, and – an oscillating mass (4). 11. Mechanical movement (1) according to claim 10, comprising a plate (500), the reference part comprising at least a part of said plate (500). 12. Mechanical movement (1) according to claim 10, comprising a bridge, the reference part comprising at least part of said bridge. 13. Mechanical movement (1) according to claim 10, comprising a cavity (50) for housing said timepiece mechanism (10). 14. Watch comprising the timepiece mechanism (10) according to one of claims 1 to 9 or the mechanical movement (1) according to one of claims 10 to 13.