Lock intended for limiting the axial displacement of a moving part of a timepiece movement and timepiece movement comprising same

Abstract

The invention relates to a lock (10) intended to limit the axial movement of a moving part (21) of a watch movement (20), said lock (10) being characterized in that it comprises a head (11) arranged at the end of a rod (12) extending along a longitudinal axis of revolution, said head (11) extending radially with respect to the rod (12) and comprising on a portion of its periphery, a radial projection (110) intended to be arranged opposite said moving part (21), and comprising, at the interface with the rod (12), a support base (111) by which the lock (10) is intended to rest against a structure (22) of the watch movement (20).

Description

Technical field of the invention

[0001] The invention falls within the field of watchmaking, and relates more particularly to a lock intended to limit the axial movement of a moving part of a watch movement.

[0002] In a particularly advantageous application of the present invention, the moving part is constituted by the hour wheel. Technological background

[0003] In a watch movement of a timepiece, the vertical play, that is to say the axial movement, of a moving part, for example a wheel, is generally limited by the dial or by a structural element of the watch movement, such as a bridge or a plate.

[0004] More specifically, in the case of a moving part consisting of the hour wheel, the axial movement is generally limited by the dial, or when the timepiece does not have a dial, for example in the case of a so-called "skeleton watch", the axial movement of the hour wheel is limited by the minute bridge.

[0005] While generally satisfactory for providing axial stops for the moving part, these solutions require relatively lengthy and tedious procedures to remove the moving part from the watch movement, for example, during maintenance. Indeed, it is first necessary to remove the dial or structural element before the moving part can be removed.

[0006] Furthermore, these solutions can generate difficulties in controlling mechanical play, and more specifically in controlling the value of the limit of the permissible axial movement of the moving part, due to possible dimensional uncertainties or possible deformations of the dial or structural element.

[0007] Document EP 3 070 345 A1 on behalf of Rolex SA describes a rivet intended to limit the axial movement of a watch movement. Summary of the invention

[0008] The invention solves the aforementioned drawbacks by proposing a solution that allows a moving part to be axially maintained in a watch movement while facilitating a possible removal operation of said moving part.

[0009] Another objective of the invention is to contribute to controlling the value of the limit of the permissible axial deflection of the moving part.

[0010] To this end, the present invention relates to a lock intended to limit the axial movement of a moving part of a watch movement, said lock comprising a head arranged at the end of a rod extending along a longitudinal axis of revolution.

[0011] The head extends radially from the stem and has, on a portion of its periphery, a radial projection intended to be positioned opposite the moving part. The head also has, at its junction with the stem, a support base on which the lock is intended to rest against a structure of the watch movement.

[0012] According to the invention as claimed, the base has a central overthickness extending around the stem so as to limit the bearing surface of said base on the structure of the watch movement.

[0013] In particular embodiments, the head has a relief adapted to cooperate with a tool so as to subject said head to a moment of force around the longitudinal axis of the rod.

[0014] In particular embodiments, the stem has an annular groove attached to the head.

[0015] In particular embodiments, the stem has an annular boss.

[0016] In particular embodiments, the radial projection includes a chamfer or fillet intended to be opposite the moving part.

[0017] In particular embodiments, the head has a flat surface parallel to the longitudinal axis of the stem, intended to be arranged to bear against a bearing surface of the structure of the watch movement.

[0018] In particular embodiments, the free end of the rod has a chamfer.

[0019] According to another object of the present invention, the present invention also relates to a clock movement comprising a moving part arranged on a structure of said clock movement, said structure comprising a housing in which a lock as described above is engaged.

[0020] The lock is engaged in the housing in a movable way by rotation around the longitudinal axis of the rod, between a position called "disengagement position", in which the radial projection is set back from the moving part, and a position, called "locking position", in which the radial projection is opposite the moving part.

[0021] In particular embodiments, the lock is configured so that, when arranged in the locking position, the radial projection is arranged at a distance from the moving part.

[0022] In particular embodiments, the structure includes at least two housings distributed around the mobile, in each of which a lock is engaged. Brief description of the figures

[0023] Other features and advantages of the invention will become apparent from the following detailed description, given by way of non-limiting example, with reference to the accompanying drawings in which: there figure 1 represents a perspective view from below of a lock according to a preferred embodiment of the invention; the figure 2 represents a top-down perspective view of the lock of the figure 1 ; there figure 3 represents a top view of part of a watch movement featuring a lock according to the figure 1 ; there figure 4 represents a cross-sectional view of a lock according to the figure 1 fixed to a clockwork mechanism according to the figure 3 . Detailed description of the invention

[0024] There figure 1 shows a lock 10 intended to limit the axial movement of a mobile 21 of a clock movement 20. Such a mobile 21 can be made up of an hour wheel, a date disc, a moon phase disc, etc.

[0025] The mobile 21 is arranged on a structure 22 of the watch movement 20 which includes at least one housing 220 in which a lock 10 is intended to be engaged in a movably rotating manner, as seen in the cross-sectional view of the figure 4 .

[0026] The lock 10 comprises a head 11 arranged at the end of a rod 12 extending along a longitudinal axis of revolution. The rod 12 is driven into the housing 220 of the structure 22 of the watch movement 20, and the head 11 is arranged to abut against said structure 22.

[0027] The rod 12 has a shape of revolution so that it can be pivoted around its longitudinal axis, relative to the structure 22 of the watch movement 20, between a locking position of the mobile 21 and a disengagement position of the mobile 21 described in detail below.

[0028] The head 11 extends radially around the rod 12 and has, on a portion of its periphery, a radial projection 110. The radial projection 110 is designed to be positioned opposite the moving part 21 when the lock 10 is in the locked position, as shown in the diagrams. figures 3 and 4 , so as to constitute a possible stop.

[0029] More specifically, as shown by the figure 4 , the lock 10 is configured so that, when arranged in the locking position, the radial projection 110 is arranged at a distance from the mobile 21 so as not to generate friction during the rotation of the latter.

[0030] As a non-limiting example, when the lock 10 is in the locking position, the lower surface 115 of the radial projection 110 is arranged to within a few tenths or hundredths of a millimeter of the moving part 21.

[0031] The lock 10 is configured so that, when it occupies the disengaged position, the radial projection 110 is set back from the mobile 21 so as not to constitute an obstacle during a possible axial displacement of the latter.

[0032] The head 11 further comprises, at the junction with the stem 12, a support base 111 by which the lock 10 is intended to rest against the structure 22 of the watch movement 20. As visible on the Figures 1 And 4 , the radial projection 110 extends radially beyond the base 111.

[0033] As shown in particular by figure 1, the base 111 may advantageously have a central overthickness 112 extending around the rod 12. The overthickness 12 is intended to constitute an axial bearing surface for the lock 10 by which it rests against the structure 22 of the watch movement 20.

[0034] The thickened section 112 has a substantially cylindrical shape of revolution whose axis coincides with the longitudinal axis of the rod 12 and comprises a cross-section whose radial dimension is reduced compared to that of the base 111 so as to limit the bearing surface of said base 111 on the structure 22 of the watch movement 20. The thickened section 112 thus reduces friction during the pivoting of the lock 10 to facilitate the rotation of the lock 10. The thickened section 112 also has the advantage of preventing damage to the structure 22 of the watch movement 20 during the rotation of the lock 10, insofar as it prevents any contact between said structure 22 and any edge or sharp corner of the head 11 during the movement of the lock 10.

[0035] In order to be able to be driven in rotation, the head 11 may have a relief 13 adapted to cooperate with a tool so as to subject said head 11 to a moment of force around the longitudinal axis of the rod 12.

[0036] In the preferred example of implementation shown on the figures 1 to 4 The relief 13 is formed by a groove designed to cooperate with the blade of a flathead screwdriver. The relief 13 is formed on an upper surface 114 of the head 11, opposite a lower surface 115 designed to be oriented towards the structure 22 of the watch movement 20.

[0037] The radial projection 110 extends radially to a free end and includes, between said free end and a surface corresponding to the lower surface 115 of the head 11, a chamfer or fillet 113 intended to be positioned opposite the moving part 21 when the lock 10 is in the locked position. This feature eliminates any sharp edge or angle that could damage the moving part 21 when the lock 10 is rotated between the locked and unlocked positions.

[0038] Advantageously, the head 11 may include at least one flat surface 116 parallel to the longitudinal axis of the rod 12, intended to be arranged to bear against a bearing surface (not shown in the figures) of the structure 22 when said lock 10 occupies the release position or the locking position.

[0039] Preferably, as illustrated on the figures 1 to 4, the head 11 has two opposite parallel flat surfaces 116 forming lateral sides of said head 11. Thus, the release position or the locking position can correspond to either of two angular positions reached by pivoting the lock 10 in one direction of rotation or the other until one or the other of the flat surfaces 116 comes to rest against a support surface of the structure 22 of the watch movement 20 provided for this purpose.

[0040] The rod 12 preferentially and advantageously includes an annular groove 120 adjacent to the head 11. This groove 120 allows to accommodate any burrs of the structure 22 of the watch movement 20 or any material chips generated during the engagement of the rod 12 in the structure 22 of the watch movement 20.

[0041] Furthermore, as shown on the figures 1, 2 And 4The rod 12 advantageously features an annular boss 121. Such a boss 121 reduces the force required to drive the rod 12 in, thus eliminating any risk of deformation of the watch movement structure 22 20 during the insertion of the rod 12. Furthermore, this feature has the advantage of reducing the torque required to rotate the lock 10, thereby preventing the risk of shearing the lock head 11 during its rotation between its locking and unlocked positions.

[0042] Advantageously, the free end of the rod 12 may have a chamfer 122 to facilitate the engagement of said rod 12 in the housing 220 of the structure 22 of the watch movement 20, in order to position said lock 10 for its insertion.

[0043] Furthermore, the portion of the rod 12 between its free end and the boss 121 also allows, due to its reduced section compared to that of said boss 121, to guide the introduction of said rod 12 into the housing 220 before the firing of said lock 10.

[0044] Preferably, the structure 22 of the watch movement 20 has several housings 220 distributed around the mobile 21, so that the watch movement 20 includes several locks 10 respectively housed in said housings 220 and adapted to limit the axial movement of said mobile 21.

[0045] More specifically, in an example of an embodiment not shown in the figures, the clock movement 20 has three locks 10 distributed around the mobile 21, for example consisting of an hour wheel.

[0046] One of the advantages of the present invention is that it allows watch movements to be supplied with the hour wheel assembled, thus saving the customer of said watch movements from having to assemble said hour wheels into the watch movements themselves.

[0047] More generally, it should be noted that the implementation and realization methods considered above have been described as non-limiting examples, and that other variants are therefore conceivable within the framework of the annexed claims.

Claims

1. A bolt (10) intended to limit the axial travel of a moving body (21) of a horological movement (20), said bolt (10) including a head (11) arranged at the end of an arbor (12) extending according to a longitudinal axis of revolution, said head (11) extending radially with respect to the arbor (12) and including over a portion of its periphery, a radial addendum (110) intended to be arranged opposite said moving body (21), and including, at the junction with the arbor (12), a bearing base (111) through which the bolt (10) is intended to rest against a structure (22) of the horological movement (20), said bolt (10 being characterised in that the base (111) has a central overthickness (112) extending around the arbor (12) so as to allow limiting the bearing surface of said base (111) on the structure (22) of the horological movement (20).

2. The bolt (10) according to claim 1, wherein the head (11) includes a relief (13) adapted to cooperate with a tool so as to subject said head (11) to a force moment about the longitudinal axis of the arbor (12).

3. The bolt (10) according to one of claims 1 or 2, wherein the arbor (12) includes an annular groove (120) contiguous to the head (11).

4. The bolt (10) according to one of claims 1 to 3, wherein the arbor (12) includes an annular boss (121).

5. The bolt (10) according to one of claims 1 to 4, wherein the radial addendum (110) includes a chamfer or a fillet (113) intended to face the moving body (21).

6. The bolt (10) according to one of claims 1 to 5, wherein the head (11) includes a planar surface (116) parallel to the longitudinal axis of the arbor (12), intended to be arranged bearing against a bearing surface of the structure (22) of the horological movement (20).

7. The bolt (10) according to one of claims 1 to 6, wherein the free end of the arbor (12) includes a chamfer (122).

8. A horological movement (20) comprising a moving body (21) arranged on a structure (22) of the horological movement (20), said structure (22) comprising a housing (220) in which a bolt (10) according to one of claims 1 to 7 is fitted, so as to be movable in rotation about the longitudinal axis of the arbor (12), between a position called "unlocking position", in which the radial addendum (110) is set back with respect to the moving body (21), and a position, called "blocking position" in which the radial addendum (110) faces the moving body (21).

9. The horological movement (20) according to claim 8, wherein the bolt (10) is configured so that, when it is arranged in the blocking position, the radial addendum (110) is arranged at a distance from the moving body (21).

10. The horological movement (10) according to one of claims 8 or 9, wherein the structure (22) comprises at least two housings (220) distributed around the moving body (21), in each of which a bolt (10) is fitted.

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