CH706762A2 - Timepiece wheel with flexible teeth. - Google Patents

Abstract

The invention relates to a timepiece wheel (1) with flexible teeth, comprising a plurality of spokes each comprising at least one tooth at the distal end of a flexible arm (4) projecting from a hub around a pivot axis (D) of said wheel (1). Each said spoke comprises hooking means (6) and complementary hooking means (7), arranged to cooperate respectively with said complementary hooking means (7) or / and said hooking means (6) which comprises a said immediately adjacent radius, in traction or push contact in certain flexion positions of at least one of said arms (4) of at least one of said neighboring spokes, in order to distribute the bending forces between said radius including said arm (4 ) is flexed, and at least one of its so-called neighboring rays.

Description

Field of the invention

The invention relates to a clock wheel with flexible teeth, comprising a plurality of spokes each having at least one tooth at the distal end of a flexible arm and projecting from a hub around a pivot axis of said wheel. The invention also relates to a watchwheel comprising at least one such wheel.

The invention also relates to such a watch movement comprising at least one such gear.

The invention further relates to a watch comprising at least one such movement.

The invention relates to the field of clockwork mechanisms comprising a gear train.

Background of the invention

The advent of new technologies, such as "MEMS" and "LIGA ©" type fabrications, and new materials, such as silicon, have made it possible to develop fully or partially flexible watch wheels, which makes it possible to the design of wheels with catch-up clearance, and guaranteeing the achievement of good yields thanks to minimal friction losses.

However, these wheels, which often have thin flexible blades, have a limited resistance in service, because of unavoidable shocks on watches, or constraints brought by the manipulations of the watchmaker, for example when laying needles, and whose intensity can go beyond the resistance of such a blade.

Summary of the invention

The invention proposes to provide the clock wheels with flexible teeth of improvements to give them a higher resistance to deformation during handling, and improve their impact resistance.

The principle is the distribution of forces greater than those related to normal walking between the tooth (or teeth) in meshing, with the teeth that precede or / and follow.

For this purpose, the invention relates to a clock wheel with flexible teeth, having a plurality of spokes each having at least one tooth at the distal end of a flexible arm and protruding from a hub around a pivoting axis of said wheel, characterized in that each said spoke comprises hooking means and complementary attachment means, arranged to cooperate respectively with said complementary attachment means and / or said hooking means that comprises a said immediately adjacent radius, in traction or thrust contact in certain bending positions of at least one of said arms of at least one of said neighboring radii, for distributing the bending forces between a said radius, said arm is flexed, and at least one of its so-called neighboring rays.

The invention also relates to a clockwork comprising at least one such wheel.

The invention also relates to such a watch movement comprising at least one such wheel.

The invention further relates to a watch comprising at least one such movement.

Brief description of the drawings

Other features and advantages of the invention will appear on reading the detailed description which follows, with reference to the accompanying drawings, in which: <tb> fig. 1 <SEP> shows, schematically and in plan view, a part of a train comprising a flexible gear wheel according to the invention, in meshing position with another wheel; <tb> fig. 2 <SEP> shows, schematically and in front view, a flexible gear wheel according to the invention, comprising a first toothing and a second toothing arranged alternately with each other; <tb> fig. 3 <SEP> is a detail of FIG. 1, in normal operation; <tb> fig. 4 <SEP> represents, similarly to FIG. 3, a wheel variant according to the invention; <tb> fig. <SEP> represents the variant of FIG. 3, during a shock applied to an antagonist wheel; <tb> fig. 6 <SEP> represents, similarly to FIG. 3, a wheel variant according to the invention with a single toothing of which all the spokes are identical; <tb> figs. 7 and 8 <SEP> represent a gear train with a flexible gear wheel according to the variant of FIG. 1, where the points of contact are highlighted by arrows, and FIG. 8 is shown with more reinforcement than FIG. 7; <tb> fig. 9 <SEP> represents, in the form of a block diagram, a watch incorporating a movement incorporating a gear train with a wheel according to the invention.

Detailed Description of the Preferred Embodiments

The invention relates to the field of clockwork mechanisms comprising a cog, and, in particular, the flexible gear wheels.

The invention is applicable to different wheel geometries, of which only a non-limiting example is illustrated in the figures. The invention is, in particular and not limited to, applicable to wheels made according to processes of the "MEMS", "LIGA ©" or similar type, and / or in materials such as silicon, or its oxides, or mono diamond. or polycrystalline, or the like.

The principle of the invention consists in the distribution of forces greater than those related to normal walking between the tooth (or teeth) in meshing, with the teeth that precede or / and follow.

Thus, the invention relates to a clock wheel 1 with flexible teeth, having a plurality of spokes 2. Each spoke 2 comprises at least one tooth 3 at the distal end of a flexible arm 4. This flexible arm 4 protrudes from a hub 5 about a pivot axis D of the wheel 1, either radially as shown in the figures, or according to a particular profile, in an arc or curve, or in profile. S, or other.

In a particular application illustrated in FIGS. 1 to 5, 7 and 8, the wheel 1 comprises a plurality of such teeth 10 different from each other, coplanar in the same plane P perpendicular to the pivot axis D, and arranged alternately with each other. Such a wheel 1 with at least two different teeth, including a first toothing 11 and a second toothing 12, is common in the known watchmaking achievements, which is why it is illustrated in more detail. Fig. 2 shows a general case with two sets of teeth 11 and 12, the first toothing comprises teeth 31A to 31F carried by arms 41A to 41F, the second set of teeth 32A to 32F carried by arms 42A to 42F.

In another application illustrated in FIG. 6, the wheel 1 has a single set of teeth 10, with radii 2 all identical. In the particular and nonlimiting application of FIG. 6, these spokes 2 are arranged with a constant angular pitch at the periphery of the wheel 1.

According to the invention, each spoke 2 comprises hooking means 6 and complementary attachment means 7, which are arranged to cooperate respectively with complementary attachment means 7 and / or attachment means 6 that includes another radius 2 immediately next door. These attachment means 6 and complementary gripping means 7 of two neighboring spokes cooperate in pulling or pushing contact, in certain bending positions of at least one of the arms 4 of at least one of these two neighboring spokes 2 , to distribute the bending forces between a radius 2 whose arm 4 is flexed, and at least one of its neighboring radii 2.

Preferably, in the free state, the attachment means 6 of a radius and the complementary attachment means 7 of the neighboring radius are not in contact with each other, and are separated by a corresponding game at least at the normal bending of the arms 4 of these spokes during the transmission of energy between the wheel 1 and a counter-wheel 50.

The hooking cooperation can be done between firstly a first radius 2 subjected to a disturbance resulting in a significant flexion of its arm 4, in particular during an impact on at least one of the two wheels 1 , 50, and secondly a second radius 2AM upstream and / or a third radius 2AV downstream of the first radius. Depending on the magnitude of the disturbance and therefore the deflection of the first radius, the latching cooperation can still be done with other rays, upstream of the second upstream beam 2AM, and / or downstream of the third downstream radius 2AV.

This cooperation in contact with two radii with each other, in certain flexion positions of their arms 4, thus allows the bending forces to be distributed on the neighboring radii 2 of the one or those whose arm 4 has sagged.

In a particular embodiment and preferred illustrated by the figures, but not limited to, this toothing 10, or each toothing 10 if there are several, has a plurality of teeth 30 identical to each other and distributed equidistantly to the periphery of the wheel 1.

In a particular and preferred embodiment illustrated by the figures, but not limited to, at least one toothing 10 comprises a plurality of spokes 20 identical to each other and distributed equidistantly around the wheel 1.

In the embodiment of FIGS. 1 to 5, 7 and 8, the wheel 1 comprises a plurality of teeth 10 different from each other, coplanar in the same plane P perpendicular to the pivot axis D of the wheel 1, and arranged alternately with each other. The figures illustrate the example of a first toothing 11 and a second toothing 12, it is nevertheless possible that the wheel 1 has a greater diversity of teeth distributed over its periphery.

Preferably, the wheel 1 according to the invention is designed to transmit the effect of a disturbance applied in any direction or direction to one or more of its spokes 2. Also preferably the means of 6 and the complementary attachment means 7 are advantageously designed to work both in traction, in which case they cooperate in a true drive engagement relationship, in compression, in which case they cooperate in abutment abutment with a antagonistic zone of adjacent radius 2, this antagonistic zone possibly consisting of the attachment means 6 and the complementary attachment means 7 of the neighboring radius, and / or in the arm 4 of the neighboring radius, and / or in a tooth 3 of the neighboring radius.

As visible in FIGS. 1 to 5, 7 and 8, the fastening means 6 and the complementary fastening means 7 are arranged to cooperate together in tension, for driving a first radius 21 of a first toothing 11 by a second radius 22 adjacent to the first spoke 21 and that comprises a second toothing 12.

In the case of a single toothing 10, as in FIG. 6, the attachment means 6 and the complementary attachment means 7 of the different adjacent radii 2 cooperate in a similar manner.

[0030] Advantageously, in the case of FIGS. 1 to 5, 7 and 8, the fastening means 6 and the complementary fastening means 7 are arranged to cooperate in abutment abutment, together and / or with the adjacent radius 20, at abutment bearing surfaces. they comprise, when a first spoke 21 is brought together with a first toothing 11 and a second radius 22 adjacent to the first spoke 21 and comprises a second toothing 12. In the case of a single toothing 10, as in fig. 6, the attachment means 6 and the complementary attachment means 7 of the two adjacent radii 2 cooperate in a similar manner in abutment abutment between neighboring radii 2.

Preferably, each spoke 2 comprises, on either side of its arm 4, on the one hand hooking means 6, and on the other hand additional fastening means 7. By convention by relative to the figures, the attachment means 6 of each spoke 2 are situated on a first so-called upstream side, and the complementary attachment means 7 are situated on a second said downstream side of the arm 4. Thus, each spoke 20, 21, 22, of each toothing 10, 11,12, comprises, on either side of an arm 40, 41, 42, hooking means 60, 61, 62, and additional attachment means 70 , 71, 72.

Preferably, all the teeth 2 of the wheel 1 are all of the same pitch diameter DP, and the various gripping means 6 and complementary gripping means 7 cooperate with each other in an annular zone of maximum diameter less than the diameter. primitive DP.

In an advantageous embodiment illustrated by FIGS. 1 to 8, the attachment means 6 or / and the complementary attachment means 7 are constituted by at least one hook 8 secured to the arm 4 that includes the radius 2 carrying the attachment means 6 or additional attachment means 7.

This hook 8 comprises a distal segment 9 which is preferably substantially radial with respect to the pivot axis D, and which carries an outer surface 91 of abutment abutment in compression and an inner surface 92 of support in traction.

Preferably, the radius 2 carries the attachment means 6 and complementary attachment means 7, in the form respectively of a first hook 86 and a second hook 87, referenced in FIG. 2: 861 for the first hook of the first toothing 11, 862 for the first hook of the second toothing 12, 871 for the second hook of the first toothing 11, 872 for the second hook of the second toothing 12.

In the case of FIGS. 1, 2, 3, 5, 7, 8 "the first hook 86 and the second hook 87 each comprise a distal segment 96, 97, substantially radial with respect to the pivot axis D, which distal segments 96, 97, are directed on the same side, either towards the outside of the wheel 1 for those of the second toothing 12, or towards the pivot axis D for those of the first toothing 11.

In the case of FIGS. 4 and 6, the first hook 86 and the second hook 87 each comprise a distal segment 96, 97, substantially radial with respect to the pivot axis D, which distal segments 96, 97 are directed in the opposite direction, one to the outside of the wheel 1 and the other to the pivot axis D. This embodiment allows to achieve 2 all identical radii.

In the case of FIGS. 1, 2, 3, 5, 7, and 8, the first hook 86 and the second hook 87 are carried by a single crosspiece 43 substantially perpendicular to the arm 4, called 4231 for the first toothing 11 and 432 for the second toothing 12.

In the case of FIGS. 4 and 6, the first hook 86 and the second hook 87 are carried by a single crosspiece 43 substantially perpendicular to the arm 4, called 431 for the first toothing 11 and 432 for the second toothing 12.

In another embodiment not illustrated by the figures, the first hook 86 and the second hook 87 are carried by the tooth 3 of the concerned radius at the outer end of the arm 4.

Figs. 3 and 5 illustrate the same mechanism, first in normal meshing, then in a shock simulated by an arrow and the abrupt displacement, in dashed line, of a tooth 51 of a wheel 50 antagonist of the wheel 1. This tooth 51 drives the tooth 31A of the radius 2, which causes, by traction, the radius 2AM immediately upstream, a first inner surface 65 of the hook 861 resulting in a third internal surface 67 of the hook 872. The spoke 2 further drives, by pushing , the radius 2AV immediately downstream, by supporting a fourth outer surface 68 on an arm bearing surface 69 of the arm 42N, and / or by pressing an arm bearing surface 69 of its arm 41A on a second outer surface 66 of the downstream beam 2AV.

FIG. 5 shows the variant of FIG. 3, during a shock applied to an opposing wheel. According to the invention, the stops work essentially with the teeth out of engagement.

An advantage of the invention is that the stops ensure that the following teeth, during bending, mesh correctly on the next tooth, with entry into the toothing without bracing, which ensures the pitch of the toothing when flexions of teeth.

Figs. 7 and 8 show a gear with a flexible gear wheel according to the variant of FIG. 1, in this case preferably a wheel of second, where are highlighted by arrows the contact points P, and where fig. 8 is shown with more reinforcement than FIG. 7, which is visualized by the upper flexion of the arms 4.

In a particular embodiment, as shown in FIGS. 1 and 3 to 8, all the arms 4 of the spokes 2 that includes the wheel 1 are angularly equidistant. The teeth 3 carried by these arms 4 may however not be equidistant, this is the case of FIGS. 1, 3 and 5 where the teeth 3 are offset relative to the arms 4, as shown in FIG. 3 where we see that each vertex 34 of tooth 3 is offset from the point 33 of extension of the arm 4, this offset being made alternately in the upstream and downstream direction, so that the distances between tooth tops are different two by two, alternating between a small inter-tooth space and a large inter-tooth space. Thus, in this embodiment, the teeth 2 are all of the same pitch diameter DP, and the distances measured on the pitch pitch circle DP between two successive teeth are different two by two.

FIG. 2 illustrates a case in which neither the arms 4 nor the teeth 3 are equidistant, but are in pairs periodically on the periphery of the wheel.

The invention also relates to a clockwork train 100 comprising at least one such wheel 1, in combination with at least one counter-wheel 50. FIG. 3 shows the relative displacement between the wheel 1 and the counter-wheel 50, each tooth 51 of which can occupy, because of the mechanical clearances in the different pivots, two extreme relative positions 52 and 53, corresponding to extreme virtual primitive circles DP2 and DP3 . The wheel 1 with flexible teeth has the advantage of allowing these variations of center distance, thanks to the bending of each of its spokes 2. This is also the reason why, in the free state, the attachment means 6 of a radius and the complementary gripping means 7 of the adjacent radius are preferably separated by a clearance greater than or equal to the displacement caused by these normal variations of center distance.

The invention also relates to a watch movement 200 comprising at least one said gear 100.

The invention also relates to a watch 300 comprising at least one movement 200.

The application of the invention to flexible gear wheels, in particular made, as illustrated in the figures, with hooking means in the form of hooks, allows to distribute on several teeth of the teeth a force applied locally, on a single tooth or at most on two teeth of this toothing. The biasing of each tooth is greatly reduced, and the resistance of the wheel to handling and shock is improved, without impairing its play catching properties and performance qualities. The hooks between the teeth reinforce the abutment effect between the teeth, and allow to distribute the bending forces, not only on the previous teeth, but also on the following ones.

Claims (20)

1. Clockwheel (1) with flexible toothing, comprising a plurality of spokes (2) each comprising at least one tooth (3) at the distal end of a flexible arm (4) projecting from a hub ( 5) about a pivot axis (D) of said wheel (1), characterized in that each said spoke (2) comprises hooking means (6) and complementary attachment means (7), arranged to cooperate respectively with said complementary attachment means (7) and / or said attachment means (6) that comprises a said radius (2) immediately adjacent, in traction or thrust contact in certain bending positions d at least one of said arms (4) of at least one of said adjacent radii (2), for distributing the bending forces between a said spoke (2) of which said arm (4) is flexed, and at least one of its said neighboring rays (2). 2. Wheel (1) according to the preceding claim, characterized in that said wheel (1) comprises at least one toothing (10) having a plurality of teeth (30) identical to each other and distributed equidistantly to the periphery of said wheel (1). 3. Wheel (1) according to the preceding claim, characterized in that said at least one toothing (10) comprises a plurality of radii (20) identical to each other and distributed equidistantly around said wheel (1). 4. Wheel (1) according to claim 2, characterized in that said wheel (1) comprises a plurality of said teeth (10) different from each other, coplanar in the same plane (P) perpendicular to said pivot axis (D), and arranged alternately with each other. 5. Wheel (1) according to the preceding claim, characterized in that said attachment means (6) and said complementary attachment means (7) are arranged to cooperate together in traction, for the training of a first radius (21) a first (11) said toothing (10) by a second radius (22) adjacent said first radius (21) and that comprises a second (12) said toothing (10). 6. Wheel (1) according to claim 4, characterized in that said attachment means (6) and said complementary attachment means (7) are arranged to cooperate abutment abutment together or / and with a said radius (2) neighbor, at abutment abutment surfaces that they comprise, at the approach of a first radius (21) of a first toothing (11) and a second radius (22) adjacent to said first radius (21) and that comprises a second toothing (12). 7. Wheel (1) according to one of the preceding claims, characterized in that each said spoke (2) comprises, on either side of a said arm (4), a first side of said means d hooking (6) and the opposite side of said complementary attachment means (7). 8. Wheel (1) according to one of the preceding claims, characterized in that said teeth (3) are all the same pitch diameter (DP), and in that said attachment means (6) and means of complementary hooking (7) cooperate with each other in an annular zone of maximum diameter less than said pitch diameter (DP). 9. Wheel (1) according to one of the preceding claims, characterized in that said attachment means (6) and / or said complementary attachment means (7) are constituted by at least one hook (8) secured to the arm (4) that includes said radius (2) carrying said hooking means (6) or complementary attachment means (7). 10. Wheel (1) according to the preceding claim, characterized in that said hook (8) has a distal segment (9) substantially radial with respect to said pivot axis (D) and carrying an outer surface (91) of pressing abutment in compression and an inner surface (92) of support in traction. 11. Wheel (1) according to claim 9 or 10, characterized in that said spoke (2) is carrying said hooking means (6) and said complementary hooking means (7), respectively in the form of a first (86) said hook (8) and a second (87) said hook (8). 12. Wheel (1) according to the preceding claim, characterized in that said first hook (86) and said second hook (87) each comprise a distal segment (96; 97) substantially radial with respect to said pivot axis (D), which distal segments (96; 97) are directed on the same side or outwardly of said wheel (1) or toward said pivot axis (D). 13. Wheel (1) according to claim 11, characterized in that said first hook (86) and said second hook (87) each comprise a distal segment (96; 97) substantially radial with respect to said pivot axis (D), which distal segments (96; 97) are directed in opposite directions, one outwardly of said wheel (1) and the other toward said pivot axis (D). 14. Wheel (1) according to claim 11, characterized in that said first hook (86) and said second hook (87) are carried by a cross member (43) substantially perpendicular to said arm (4). 15. Wheel (1) according to claim 11, characterized in that said first hook (86) and said second hook (87) are carried by said tooth (3) of said radius (2) concerned at the outer end of said arm ( 4). 16. Wheel (1) according to one of the preceding claims, characterized in that all said arms (4) of said spokes (2) that comprises said wheel (1) are angularly equidistant. 17. Wheel (1) according to one of the preceding claims, characterized in that said teeth (2) are all of the same pitch diameter (DP), and in that the distances measured on the pitch pitch pitch circle (DP) between two successive teeth are different two by two. 18. Clockwork (100) having at least one wheel (1) according to one of the preceding claims. 19. A watch movement (200) comprising at least one said wheel (100) according to the preceding claim. 20. Watch (300) comprising at least one movement (200) according to the preceding claim.