CH713302A2 - Device for converting displacements, for example for automatic winding systems of timepieces. - Google Patents

Abstract

The invention relates to a displacement conversion device (1) adapted to convert an input rotation in any direction into an output rotation in a single predetermined direction, comprising: an eccentric (5) arranged to be driven by said input rotation; an output mobile (23) having a driving surface (23a); a frame (17) carrying a set of drive arms (21) arranged to drive said output mobile (23) in said single predetermined direction, said eccentric (5) being arranged to move in translation said frame (17). According to the invention: said set of driving arms comprises at least three drive arms (21) whose ends are arranged to cooperate with said drive surface (23a); and said frame (17) is guided by a flexible guide (25) comprising at least four flexible blades (25a, 25d, 25f, 25g) arranged as an X-Y table to impart to said frame (17) substantially two degrees of freedom in translation and substantially no degree of freedom in rotation. The invention has for example as a field of application the automatic winding systems of timepieces.

Description

Description TECHNICAL FIELD [0001] The present invention relates to the field of displacement converters. More particularly, it relates to a displacement conversion device which serves to convert a rotation in any direction into a rotation in a single predetermined direction. This type of device finds particularly, but not exclusively, its application in automatic winding timepiece systems.

State of the art [0002] The document CH 336 755 describes an automatic winding device comprising an oscillating mass pivotally mounted on a support and rotatably connected to an eccentric cam. This cam rotates in a slot that includes a slide. The latter comprises a pair of nozzles which interact with a wheel röchet which is in kinematic connection with a motor member such as a mainspring, in order to reassemble it. The slide is guided so that it can perform reciprocating movements in a single degree of freedom in translation, that is to say rectilinear displacements, under the control of the eccentric cam. The nozzles are located on either side of the ratchet wheel to ensure that it is rotated in a single direction of rotation when the slide moves, regardless of the direction of displacement.

In doing so, when the oscillating mass pivots, the slide is driven in translation by the eccentric cam, and the ratchet wheel is driven by the nozzles.

However, if the rotation of the eccentric cam is represented by a right vector whose point of application is the center of the cam and whose direction is perpendicular to the line connecting the axis of rotation of the cam in the center of the cam, only the component of this vector parallel to the direction of movement of the slider is converted into rotation of the ratchet wheel, the perpendicular component being lost. Therefore, the effectiveness of such an arrangement is not satisfactory because of the lost path of the oscillating mass.

Moreover, the slide rubs on its guide system and on the frame on which it is mounted, which is also detrimental to its performance.

The object of the present invention is to overcome the aforementioned drawbacks, and thus to provide a displacement conversion device having an improved performance.

Disclosure of the Invention [0007] More specifically, the invention relates to a displacement conversion device adapted to convert an input rotation in any direction into an output rotation in a single predetermined direction. This device comprises an eccentric arranged to pivot according to said input rotation, an output mobile having a driving surface (which may be cylindrical, planar, similar to a polygon, or other), and a frame carrying a game drive arms arranged to directly or indirectly drive said mobile output in said single predetermined direction, said eccentric being arranged to move in translation said frame.

According to the invention, said set of drive arms comprises at least three drive arms, the ends of which are arranged to cooperate with said drive surface. Said frame is guided by a flexible guide comprising at least four flexible blades arranged as an X-Y table in order to confer on said frame substantially two degrees of freedom in translation along its plane and substantially no degree of freedom in rotation.

This arrangement ensures that the output mobile is rotated independently of the position of the eccentric, to greatly reduce the lost path of the eccentric, and the energy losses due to friction are minimized by the use of a flexible guide instead of a conventional guide since the frame is suspended and therefore does not rub on pads or the like. In doing so, the efficiency of the device is significantly improved. Furthermore, the claimed arrangement is relatively simple to assemble and compact, In addition, it requires relatively few parts and allows freedom and flexibility of construction that offer new perspectives when developing or adapting a caliber. The output mobile may be intended to be kinematically connected, for example, with a cylinder containing a mainspring, with a generator associated with an accumulator, or the like.

In a variant, said eccentric may be linked to said frame via at least one ball bearing, which further reduces the energy losses due to friction present in the device whose performance is thus still improved. Throughout this specification, the term "bound" includes not only direct links (at least partially integral elements, elements from the same coin, or other), but also indirect links (elements connected by a gear train, or other ).

Alternatively, said drive arm, said frame, and possibly also at least a portion of said flexible guide can be from the same room, and may possibly be in the same plane.

In a variant of construction, the displacement conversion device comprises an eccentric arranged to rotate according to said input rotation, a mobile output, and a frame carrying a set of drive arms arranged to drive directly. or indirectly said mobile output according to said single predetermined direction.

According to this variant of construction, said frame is integral in rotation with said output mobile, and said set of driving arms comprises at least three drive arms whose ends are arranged to cooperate with a driving surface ( which can be cylindrical, planar, comparable to a polygon, or other). Said driving surface is guided by a flexible guide comprising at least four flexible blades arranged as XY table in order to give to said driving surface substantially two degrees of freedom in translation along its plane and substantially no degree of freedom in rotation said eccentric being arranged to translate said driving surface.

In this variant, the positions of said frame carrying said set of drive arms and said drive surface have been reversed with respect to the first variant, without affecting the overall operation of the device or the above-mentioned advantages. .

In a variant, said eccentric may be connected to said driving surface via at least one ball bearing, which further reduces the energy losses by friction present in the device whose output is thus found further improved.

Alternatively, a movable member comprises said drive surface, said movable member and at least a portion of said flexible guide can be from the same room, and may possibly be in the same plane.

In a variant, said drive arms and said frame can be from the same room, and may possibly be located in the same plane.

In each of the aforementioned variants, the driving surface may be an inner or outer cylindrical surface.

In each of the aforementioned variants, said flexible guide may comprise a first pair of flexible blades, parallel to each other, and a second pair of flexible blades, also parallel between them, the blades of the first pair and the blades of the second pair forming an angle different from 0 ° between each pair, said angle preferably being substantially 90 °.

In each of the aforementioned variants, said drive arms may be evenly distributed angularly, that is to say that, for a number N of arms, the arms are distributed at the rate of one arm par3607N around a point, the angle formed by two successive arms is therefore also 3607N.

In a variant, said ends of said drive arms may each comprise a spout or a hook, said drive surface then having a serrated toothing.

In an alternative embodiment, said ends of said drive arm may each comprise a first friction surface, said drive surface then having a second friction surface.

In a variant, the device may be arranged in such a way that said first friction surface and said second friction surface can not slide relative to one another during the driving of one of said friction surfaces by the other. In doing so, no anti-return system should be provided as the arms and surface act as a self-locking one-way drive.

Alternatively, the device can be arranged in such a way that said first friction surface and said second friction surface can slide relative to one another during the driving of one of said friction surfaces by the other when a critical tangential force is exceeded. Here, the arms can disengage from the surface when a critical torque is reached. In doing so, the device can provide over-spring protection for a motor-spring, and thus a slippery flange (or the like) is rendered superfluous. Therefore, the portion of the volume in a barrel that is typically occupied by the sliding flange and the final turn of the mainspring is available for the mainspring. The available energy can thus be increased, possibly by arranging a system preventing the mobile from rotating in the wrong direction, such as a driving surface, which may comprise a sawtooth or a friction surface, arranged to interacting with the end of a drive arm, which may comprise a spout or a friction surface, this device may be on the output mobile, on the drive member or between these two components.

Advantageously, at least one of said ends of said drive arm is in contact with said drive surface at any time, since a loss of contact generates a loss of efficiency.

Said device can be integrated with an automatic winding system to raise a mechanical accumulator (such as a motor-spring) or electric (such as a battery or a capacitor), the system may further comprise a steering wheel. kinematic connection with said eccentric.

Finally, this automatic winding system can be included in a portable object such as a timepiece (which can be a mechanical watch, an electronic watch, or other), a mobile phone, or other. In this case, said flexible guide can be rotatably mounted around the axis of rotation of said mobile output and relative to a fixed portion of said portable object, to also allow manual winding. One could consider, for example, to bind the guide kinematically to a rotating bottom, a rotating bezel, or a winding crown.

BRIEF DESCRIPTION OF THE DRAWINGS Further details of the invention will emerge more clearly on reading the description which follows, made with reference to the appended drawings in which:

Fig. 1a-1c are various schematic views of a first variant of a displacement conversion device according to the invention;

Fig. 2a-2c are various schematic views of a second variant of a displacement conversion device according to the invention;

Fig. 3a-3c are various schematic views of a third variant of a displacement conversion device according to the invention; and

Fig. 4a-4c are various schematic views of a fourth variant of a displacement conversion device according to the invention.

Embodiment (s) of the invention [0029] FIGS. 1a-c illustrate a first variant of a displacement conversion device 1 according to the invention, in the context of an automatic winding system 3 for a timepiece. The device 1 can also be applied to other products, for example portable objects that store energy in mechanical or electrical form, such as mobile phones, or the like.

The device 1 comprises an input in the form of an eccentric 5, which is integral in rotation with a steering wheel 7 comprising a heavy sector 7a. This flywheel is mounted on a support (not shown) via a first ball bearing 9, whose inner ring is fixed to the support by a central screw, or by any other appropriate means. The eccentric may alternatively generate itself the input rotation, or may be linked to the wheel 7 by any wheel.

The eccentric 5 takes the form of a ring mounted eccentrically on the flywheel 7 so that the axis of rotation 11 of the flywheel 7 does not coincide with the geometric center 13 of the eccentric 5. Therefore, when the steering wheel 7 pivots relative to the support, the geometric center 13 of the eccentric 5 orbits around the axis of rotation 11 of the flywheel 7. The steering wheel 7 and the eccentric 5 can be secured to one another , which also applies to the other variants described.

In the opening of the eccentric 5 is fixed the outer ring of a second ball bearing 15, which links it to an opening 17a of a frame 17, via a connecting ring 19 fixed in said opening 17a, for example by driving. Alternatively, this ball bearing 15 can be omitted. In an alternative variant not illustrated, the eccentric may comprise three holes whose centers are on a virtual circle whose center is not coincident with the axis of rotation of the eccentric. Each hole carries a pin secured to a ball bearing cooperating with the frame 17. This variant also applies to each variant described here.

The frame 17 also comprises four drive arms 21, regularly distributed angularly around a mobile output 23, and interact with the periphery of this mobile output that can, in the context of an automatic winding, directly constituting a ratchet wheel of a cylinder or can be kinematically connected with such a wheel by means of a gear reducer. The last of these possibilities is the most usual, but the first is not excluded. Alternatively, the mobile output 23 can be kinematically connected to a rotor of an electric generator. For information, the drive arms 21 and the flexible blades 25a, 25d (see below), are illustrated in unconstrained state; in reality, they are bent and thus constrained. These arms 21 are all coplanar with the frame 17, but this is not mandatory, and one or more of these arms may be in a different plane.

To drive the mobile output 23, each drive arm 21 is provided with a hook at its free end, and the periphery of the output mobile 23 is a cylindrical drive surface 23a comprising a toothing. Sawtooth. The hooks and the teeth are arranged in known manner so that the hooks can drive the mobile 23 in a single predetermined direction of rotation, and block any pivoting of the latter in the opposite direction. The number of driving arms 21 can vary between three and a higher number determined by the space available inside the frame 17 and the shape of the arms 21. It should be noted that, unlike the situation in the document CH 336 755 mentioned above, in which one of the arms acts in traction and the other in compression, all the drive arms can work in the same direction, that is to say all in compression or all in traction. This last configuration makes it possible to eliminate the disadvantage that is the risk of buckling of stressed arms in compression. These drive arms 21 engage and disengage in sequence (and therefore are not necessarily all engaged or disengaged at the same time), to drive the mobile output 23, while preventing the latter from rotating in the opposite direction.

In the illustrated variant, the drive arms 21 are elastic (more precisely, flexible) and come integrally with the frame 17, but they can alternatively be constructed as separate pieces, pivoted on the frame 17 in a manner similar to those of the aforementioned document CH 336 755, and provided with return springs tending to keep the hooks in contact with the periphery of the mobile 23. Alternatively, they may be constituted by beams connected to the frame 17 by flexible joints .

In the variant shown, the axis of rotation 27 of the mobile 23 is offset from the geometric center 13 of the eccentric 5, so that the assembly formed by the frame 17 and the flexible guide 25 (see below) is flat and thus easily machinable from a plate of material by known manufacturing techniques. However, it is also possible to locate the mobile 23 in another plane, for example below the opening 17a, which implies a multi-level construction of the assembly 17, 25. Such manufacturing techniques include, but are not limited to wire machining, laser machining, subtractive manufacturing (DRIE), additive manufacturing (LIGA), etc.

As illustrated, the hooks are arranged to act in traction on the output mobile 23, but it is also possible to arrange the arms 21 differently, so that they have beaks adapted to push said mobile instead of the shoot.

The frame 17 is connected to the support (not illustrated) via a flexible guide 25. This flexible guide 25 comprises a first pair of parallel flexible blades 25a extending from an interface element 25b. intended to be fixed to the support, to a rigid corner 25c. This first pair of flexible blades 25a extends along the X axis and gives a degree of freedom in translation approximately along the Y axis. The rigid wedge 25c is connected directly or indirectly to the frame 17 via a second a pair of flexible blades 25d, parallel to each other, which extends along the Y axis, and gives a degree of freedom in translation approximately along the X axis. The flexible guide 25 thus constitutes an XY table. This last term designates a system in which an element can be guided substantially exclusively in translation along a plane defined by the X and Y axes. It should be noted that it is not possible to eliminate completely any deformation according to the other degrees of freedom (in rotation along the X, Y and Z axes, and in translation along the Z axis), but the stiffness of the flexible guide according to these other degrees of freedom is relatively high, such as for example 5 times, 10 times or even 20 times steeper than in translation in the XY plane. In doing so, the frame 17 is suspended by the flexible guide 25, and does not rub against fixed elements to the frame, which increases the efficiency of the device.

Alternatively, the blades may be partially flexible instead of completely flexible, for example by being made of flexible beams made via collars or other flexible parts.

On the other hand, it is not required that the flexible blades 25a, 25d have the same length (for example, the flexible blades of the pair 25a may be longer than the flexible blades of the pair 25d), or that, in a pair of flexible blades 25a, 25d, the angle formed by the straight line connecting the two recesses of the same blade and the straight line connecting the two blade recesses linked to the same other element 25b, 25c, 17 is necessarily 90 °. This also applies to all embodiments, mutatis mutandis.

Although such a blade arrangement is particularly effective, it is not mandatory that the first pair of flexible blades 25a is orthogonal to the second; the angle between these pairs can be chosen so that the two degrees of freedom are not perpendicular. For example, one could consider an angle of between 30 ° and 90 ° between the two pairs of flexible blades 25a, 25d.

With this construction, when the wheel 7 pivots, the eccentric 5 moves the frame 17 in an orbital motion in translation, without rotation. In other words, the flexible guide 25 also acts as an anti-rotation system. Regardless of the direction of the tangent of the displacement, one or more of the driving arms 21 will rotate the mobile 23. Consequently, there is no path lost by the steering wheel, which makes the device particularly difficult. effective. Moreover, since the movements of the frame 17 are small, the device amplifies the torque transmitted to the mobile 23, and can therefore avoid the use of a gear train for this purpose.

It goes without saying that the various elements of the flexible guide 25, the frame 17, and the arms 21 may be on different levels, without affecting the operation of the device 1.

Figs. 2a-c illustrate a second variant of a displacement conversion device 1 according to the invention, also in the context of an automatic winding system 3 for a timepiece. In this variant, the equivalent elements bear the same reference signs as used for FIGS. 1a-c.

In this variant, the eccentric 5 forming the input of the device is a stud carried by a fixed solidarity beam of the flywheel 7, which is pivotally connected to a support (not shown) via a first ball bearing 9 located inside the wheel 7. Again, the latter has a heavy sector 7a and the geometric center 13 of the eccentric 5 does not coincide with the axis of rotation 11 of the flywheel 7. This axis of rotation 11 is defined by the geometric center of the first ball bearing 9.

The geometric axis of the stud constituting the eccentric 5 is slightly offset relative to the axis of rotation of the wheel 7, and is connected to a flexible guide 25 via a second ball bearing 15 in the inner ring of which said stud 5 is located. The outer ring of this bearing 15 is fixed to a central part 25e of the flexible guide 25 by means of a connecting ring 19.

This flexible guide 25 has its central portion 25e supported by blades 25a, 25d, 25f, 25g, and allows the central portion 25e to remain parallel to its outer frame 25h. For this purpose, the central portion 25e is connected to an outer frame 25h via a first pair 25a of parallel blades extending from the same side of the outer frame and located on either side of the central portion 25e, and a second pair 25d of blades which are orthogonal to those of the first pair 25a and which also extend from another same side of the outer frame 25h on either side of the central portion 25e. To these pairs of blades are added a third pair 25f of blades, each extending parallel to a blade of the first pair 25a from the opposite side of the outer frame 25h, and a fourth pair 25g of blades, each extending also parallel to a blade of the second pair 25d from the other side of said outer frame 25h. Each individual blade is connected to three other blades, including a parallel blade located on the other side of the central portion 25e and two orthogonal blades respectively on each side of the central portion 25e. This connection is via respective connecting beams 25i, and the set of blades and beams is arranged to form an X-Y table. As is the case for the variant of figs. 1a-c, this flexible guide 25 has substantially two degrees of freedom, approximately along the X and Y axes, its translational stiffness is substantially higher along the Z axis than along the X and Y axes, and its rotational stiffness along the X, Y and Z axes is relatively high. It goes without saying that other geometries are possible to build the flexible guide 25.

This time, the drive arms 21 did not come from one piece with the flexible guide 25; on the other hand, they are carried by a separate frame 17, which is fixed to the central portion 25e of the flexible guide 25 via the intermediate ring 19, which passes through the opening in said central portion 25e. In doing so, the frame 17 is integral in rotation with the intermediate ring 19. The drive arms 21 are made flexible to their recesses in the frame 17 by collars arranged so that the connection between the arms 21 and the frame 17 is thinned to provide the desired elasticity. For information, the driving arms 21 and the flexible blades 25a, 25d, 25f, 25g are illustrated in the unconstrained state; in reality, they are bent and therefore constrained, the necks of the driving arms 21 being bent. Again, the arms 21 are all coplanar with the frame 17, but this is not mandatory, and one or more arms may be in a different plane.

In order to ensure that the frame 17 and the drive arms 21 do not rub against the flexible guide 25, a spacer 29 is positioned between the frame 17 and said central portion 25e, and around the intermediate ring 19, to maintain a separation perpendicular to the XY plane between these portions 17, 21, 25.

The frame 17 directly carries the four drive arms 21, regularly distributed angularly around the frame 17, which extend outwardly. Although it is possible to provide a spout or hook at the end of each drive arm and a sawtooth toothing on the output mobile 23, in the variant illustrated, these ends are rounded and s are supported under tension against a smooth cylindrical inner drive surface 23a that comprises the output mobile 23. The body of each drive arm is a substantially rigid beam, and is connected to the frame 17 via a portion elastic (more specifically flexible) 21a, the geometry of each drive arm 21 being selected so that the ends are constrained against said drive surface 23a, which has a friction surface.

The interaction between the drive arms 21 and the mobile output 23 is therefore by friction, and, in the direction of rotation of the eccentric being in a position in which a single arm 21 is brought to drive the mobile output, the arm 21 the most constrained or the least constrained, acts to drive the mobile output.

When the steering wheel 7 rotates, the eccentric 5 drives the central portion 25 of the flexible guide 25. The latter being fixed to the frame 17, one (or more) of the drive arms 21, is pressed more strongly against the cylindrical inner wall 23a of the output mobile 23, which drives the latter in the direction of the arrow. In this way, the ends of the drive arms 21 each comprise a first friction surface, and the wall 23a has a second friction surface.

In the case of the integration of the displacement conversion device 1 in an automatic winding 3, the output mobile 23 will be kinematically linked to the motor member so as to be able to reassemble it.

The use of an arrangement acting by friction has several advantages over hooks and toothing: - There is no threshold of displacement depending on the pitch of the toothing that must be crossed to drive the mobile 23, and, therefore, even small displacements of the input 5 generate a drive of the mobile output 23. The device then operates continuously rather than discrete, which increases its efficiency. - Since this threshold is removed, the eccentricity of the input 5 can be reduced compared to the variant of Figs. 1 a-c, because there is no minimal movement to cross for the ends of the arms 21 before the mobile output 23 is driven. Indeed, the frame 17 can undergo a smaller displacement under the effect of a larger force. In doing so, it is possible to remove all gear reducer, because the torque supplied to the output mobile may be sufficient to directly raise a mainspring. - In the case where the mobile output 23 can no longer rotate usefully, for example in the case where the mainspring is reassembled fully, the arrangement of the device, whose coefficient of friction between the friction surfaces, can be chosen such that the drive arm (s) 21 which engage with the driving surface 23a of the output mobile can disengage from this driving surface when a critical force tangential to the interface is exceeded. In doing so, any protective device used to prevent the mainspring from being raised excessively and capable of causing the breaking of one or more parts, such as a sliding flange, a torque limiting connection, etc., may be omitted, the useful internal volume of a given motor organ is thus increased, the amount of available energy is increased. However, in such a configuration, when all the drive arms 21 disengage, there is nothing that prevents the mainspring from driving the output mobile 23 in the wrong direction at least for torques greater than a critical torque . Therefore, in order to prevent such rotation, a system may be provided, such as a driving surface, which may have a sawtooth or friction surface, arranged to interact with the end of the system. a drive arm, which may comprise a spout or a friction surface, this device may be on the output mobile, on the drive member or between these two components. For example, one could provide such an arrangement between the mobile output 23 and a support member. - The work of the manufacturer is simplified because it is no longer necessary to define forms for the teeth and hooks or spouts associated with a compromise in terms of performance, safety, space, etc. Furthermore, the freedom of construction is improved in the form of the arms 21, which can thus more easily take various forms according to the designer's choice.

It goes without saying that the same comments on the shape of the eccentric 5, and the arrangement of various elements in different planes issued in the context of the embodiment of Figs. 1a-c also apply to this variant.

Figs. 3a-c illustrate a third variant of a device 1 according to the invention.

This variant is based on that of FIGS. 1a-c, of which it differs mainly in that the positions of the drive arms 21 and the drive surface 23a, 25o have been reversed.

In this variant, the drive arms 21, which resemble those of FIGS. 2a-c, and their frame 17 (formed as a hub), are integral in rotation with or from the same room with a non-illustrated output mobile whose frame 17 is coaxial. Instead of the frame carried by the flexible guide 25, the latter directly carries a drive surface 25o, which is formed as a circular opening in a movable member 25m. The latter has an opening 25n in which is fixed the connecting ring 19.

Therefore, when the eccentric 5 rotates, the drive surface 25o performs an orbital translation, guided by the flexible guide 25. This translation subsequently acts on the drive arms 21, thus constraining at least the one of these and exerting a force which serves to drive the frame 17 in rotation and thus to pivot the mobile output (not shown), in the same way as in the variant of Figs. 2a-c, mutatis mutandis.

Alternatively, the drive arms 21 may carry hooks in a manner similar to the variant of Figs. 1a-c, the drive surface 25o then having a serrated toothing.

Moreover, the same principle can be used to create a variant of the embodiment of FIGS. 2a-c, by reversing the positions of the assembly formed by the frame 17 and the drive arms 21, and the drive surface 23a.

Again, it goes without saying that the same comments on the shape of the eccentric 5, and the arrangement of various elements in different planes emitted in the embodiment of Figs. 1a-c also apply to this variant.

Figs. 4a-c further illustrate an embodiment of a displacement conversion device 1 according to the invention. This variant is based on that of FIGS. 3a-c, and differs from the latter with regard to the following aspects, again, the corresponding output mobile is not illustrated here.

In the first place, the frame 17, in the overall shape of a circle, carries five drive arms 21, each in the overall shape of a triangle with rounded vertices, in order to present the appearance of a star. These drive arms 21 are regularly distributed around the frame 17 and are each bonded thereto via a resilient portion 21a, in the form of a neck. Again, the drive arms 21 and the flexible blades 25a, 25d are illustrated in an unstressed state, the arms 21 thus overlapping the movable member 25m; in reality, they are bent and thus constrained, the ends of the drive arms 21 being in contact with the drive surface 25o. The movable member 25m takes the form of a ring in this embodiment, which is bonded to the interface member 25b by a flexible guide 25 whose arrangement of the blades 25a, 25d is more compact than those described above.

In this variant, the first elastic blades 25a link the interface element 25b to a two-branched element 25c which has the same function as the rigid corner of the other variants, and extend on both sides of the interface element 25b. The element 25c is shaped to bind said first elastic blades 25a to the second resilient blades 25d which are substantially perpendicular thereto in the idle state of the guide, the latter resilient blades 25d being joined to the movable member 25m.

Otherwise, this variant operates in the same way as that of FIGS. 3a-c.

In all embodiments, at least one of the drive arm 21 is in contact with the drive surface 23a, 25o at any time since a loss of contact generates a loss of efficiency. In a variant

Claims (19)

four drive arms regularly distributed angularly at a position of the eccentric for which a single drive arm 21 drives the drive surface 23a, 25o is, in the direction of rotation of the eccentric, the arm 21 the most flexed or the arm 21 the least flexed which drives the driving surface 23a, 25o, the arms moderately bent disengaging. Various other variants of the device 1 according to the invention are conceivable. For example, in the variant of FIGS. 1a-c, the drive surface 23a of the output mobile 23 may be internal or external and have a sawtooth toothing or a friction surface (as in Fig. 2a-c), each drive arm 21 then having a hook or a friction surface. Still alternatively, the variant of FIGS. 2a-c may comprise an off-center frame 17 and a movable outlet 23, and / or nipple or hook drive arms 21 and a sawtooth toothed drive surface. Its frame 17 may be external to the arms 21, as in the variant of FIGS. 1a-c, and the output mobile can be external drive surface. Furthermore, the drive arms 21 may be shaped in each variant so that they interact with a flat drive surface having a friction surface or sawtooth toothing (such as for example a toothing). edge) of the output mobile 23 or the movable member 25m, rather than with an inner or outer cylindrical drive surface as illustrated in the figures. In all the aforementioned embodiments, if the support (not shown) to which is fixed the flexible guide is movable in rotation about the axis of rotation of the output mobile and relative to a fixed element of the apparatus inside which the device 1 is arranged, a rotation of this support can rotate the mobile output, to constitute a manual winding device. To this end, the support can be kinematically linked to a rotating bottom or a rotating bezel, or to a winding crown. A system preventing the output mobile from rotating in the wrong direction, such as a drive surface, which may have a sawtooth or a friction surface, arranged to interact with the end of a drive arm , which may comprise a spout or a friction surface, can then be provided. Furthermore, the output mobile 23 can be kinematic not exclusively with a mechanical energy storage device such as a barrel containing a spring, but alternatively with an electric generator associated with a battery (such as a secondary battery, a capacitor or the like). More generally, the characteristics of each variant can be combined in multiple ways. Finally, it is noted that additional variants are also conceivable without departing from the scope of the invention as defined by the claims. claims A displacement converting device (1) adapted to convert an input rotation in any direction into an output rotation in a single predetermined direction, comprising: - an eccentric (5) arranged to be driven by said rotation of 'Entrance; - an output mobile (23) having a driving surface (23a); a frame (17) carrying a set of driving arms (21) arranged to drive said movable outlet (23) in said single predetermined direction, said eccentric (5) being arranged to move said frame (17) in translation; characterized in that: said drive arm set comprises at least three drive arms (21) whose ends are arranged to cooperate with said drive surface (23a); and - said frame (17) is guided by a flexible guide (25) comprising at least four flexible blades (25a, 25d, 25f, 25g) arranged as an XY table in order to give said frame (17) substantially two degrees of freedom in translation and substantially no degree of freedom in rotation. 2. Device (1) according to the preceding claim, wherein said eccentric (5) is connected to said frame (17) via at least one ball bearing (15). 3. Device (1) according to one of claims 1 or 2, wherein said drive arm (21), said frame (17), and optionally also at least a portion of said flexible guide (25), came from a same piece, said drive arm (21), said frame (17), and optionally also at least a portion of said flexible guide (25), being preferably in the same plane. A displacement converting device (1) adapted to convert an input rotation in any direction to an output rotation in a single predetermined direction, comprising: - an eccentric (5) arranged to be driven by said rotation of 'Entrance; - an exit mobile; - A frame (17) carrying a set of drive arms (21) arranged to drive said mobile output in said single predetermined direction, characterized in that - said frame (17) is integral in rotation with said output mobile; said set of driving arms comprises at least three driving arms (21); the ends of said driving arms (21) are arranged to cooperate with a driving surface (25o); and said driving surface (25o) is guided by a flexible guide (25) comprising at least four flexible blades (25a, 25d, 25f, 25g) arranged as an XY table to impart to said driving surface ( 25o) substantially two degrees of freedom in translation and substantially no degree of freedom in rotation, said eccentric (5) being arranged to move in translation said drive surface (25o). 5. Device (1) according to the preceding claim, wherein said eccentric (5) is connected to said drive surface (25o) via at least one ball bearing (15). 6. Device (1) according to one of claims 4 or 5 wherein a movable member (25m) comprises said drive surface (25o), said movable member (25m) and at least a portion of said flexible guide (25). have come from the same piece, said movable member (25m) and at least a portion of said flexible guide (25) being preferably in the same plane. 7. Device (1) according to one of claims 4, 5 or 6, wherein said drive arm (21) and said frame (17) came from the same room, said drive arms (21) and said frame (17) is preferably in the same plane. 8. Device (1) according to one of the preceding claims, wherein said drive surface (23a, 25o) is substantially cylindrical. 9. Device (1) according to one of the preceding claims, wherein said flexible guide (25) comprises a first pair of flexible blades (25a), parallel to each other, and a second pair of flexible blades (25d), also parallel to each other, the flexible blades of said first pair (25a) and the flexible blades of said second pair (25c1) forming an angle different from 0 ° between each of said pairs (25a, 25d), said angle preferably being substantially 90 °, 10. Device (1) according to one of the preceding claims, wherein said drive arm (21) are regularly angularly distributed. 11. Device (1) according to one of the preceding claims, wherein said ends of said drive arm (21) each comprise a spout or a hook, and wherein said drive surface (23a; 25o) comprises a toothing serrated. 12. Device (1) according to one of claims 1 to 10 wherein said ends of said drive arm (21) each comprise a first friction surface, and wherein said driving surface (23a; 25o) comprises a second friction surface. 13. Device (1) according to claim 12, arranged such that said first friction surface and said second friction surface can not slide relative to each other during the driving of one of said friction surfaces by the other. 14. Device (1) according to claim 12, arranged such that said first friction surface and said second friction surface can slide relative to each other during the driving of one of said surfaces. friction by the other when a critical tangential force is exceeded. 15. Device (1) according to one of the preceding claims, wherein at least one of said ends of said drive arm (21) is in contact with said driving surface (23a; 25o) at any time. 16. Mechanical or electrical automatic winding system (3) comprising a device (1) according to one of the preceding claims. 17. System (3) according to claim 16, further comprising a wheel (7, 7a) in kinematic connection with said eccentric (5). 18. Portable object comprising a system (3) according to one of claims 16 or 17. 19. Portable object according to claim 18, wherein said flexible guide (25) is rotatable about the axis of rotation of said mobile output (23) and with respect to a fixed portion of said portable object.