HK1206114B - Micrometric adjustment of the endshake of a timepiece wheel set - Google Patents

Description

Micrometric adjustment of the axial play of a timepiece wheel set

Technical Field

The invention concerns a timepiece movement including at least one structure carrying at least one wheel set, wherein the axial play (endshake) of said at least one wheel with respect to said at least one structure is adjustable along a pivot axis, such adjustment being possible by means of an axial play adjustment device or by means of a fitted casing, said adjustment device including at least one pivot bearing for the wheel set, said at least one bearing defining, in the axial direction of the axis, at least one axial stop for the wheel set, the adjustment device including at least one first smooth adjustment stage having a variable thickness in the axial direction, the first adjustment stage including a first part provided with a pivoting drive device that can be driven by a tool and that carries the bearing, and a second part onto which the first part is pushed by at least one elastic return device, the second component is fixed to the structure directly or via at least one housing, wherein the elastic return means is supported on the structure directly or via at least one housing; the equipped housing comprises the adjusting device and comprises the housing accommodating at least one of the first adjusting stages, wherein the second component is integrally fixed with the housing and the elastic return device is supported inside the housing.

The invention also concerns a timepiece including at least one movement of this type.

The present invention relates to the field of timepiece movements, and more particularly to the field of supporting and adjusting a timepiece wheel set.

Background

The adjustment of the axial play of the timepiece wheel set is a difficult operation performed by highly qualified professionals, usually by elastic deformation of structural elements, splints or the like, or by removing the jewel bearing and then nailing it back. The mechanism incorporates little adjustment means, since the adjustment range required is small, at most a few microns or hundredths of a millimeter, which is not possible with conventional micrometric means (e.g. male-female threads) because the required operating clearance is greater than the required adjustment range. Moreover, the space necessary for any adjustment mechanism is rarely compatible with that of a timepiece movement.

Swiss patent application No.339136A to burea techiniqued ERARD describes a timepiece bearing comprising a concentric arrangement of an element forming a bearing body and a central element carrying at least one jewel aperture. The axial position of the central element can be adjusted by rotating the central element relative to the bearing body.

Swiss patent application No.356090A to SEITZ & CO describes a bearing having an axial stop removably mounted in a bearing body which includes one of the projections which cooperates with a helical ramp contained in a nest forming the axial stop.

United states patent application No.4192136A to ROBINSON describes an axial adjustment mechanism in a timepiece based on the mating of spiral bevel segments.

U.S. patent application No.2010/188941a1 to seiko (full jieda hisgshi) describes a bearing structure having a fully axial adjustment configuration that rotatably supports the forward end of the spindle of a wheel relative to a base body, the bearing structure comprising: a bearing, a bearing support body on the outer peripheral surface of the arbor of the wheel, which bearing support body carries the bearing and has a male threaded portion, and an adjustment nut provided with a female threaded portion in threaded engagement with the male threaded portion of the bearing support body, which adjustment nut is adjusted in the timepiece movement by the base body portion in the direction of extension of the arbor of the wheel and is adapted to adjust the position of the bearing relative to the direction of extension of the arbor by means of the bearing support.

Disclosure of Invention

The invention proposes to incorporate the micrometric endshake regulating function into a clockwork within a more compact thickness, at the same time having a sensitivity that allows regulation of several microns, and being applicable to existing movements, requiring only limited and low-cost modifications of the structural parts that house the wheel set bearings whose axial play needs to be regulated. The present invention must be able to make axial clearance adjustments by external manipulation using a tool without disassembling the pre-assembled components.

The invention therefore concerns a timepiece movement including at least one structure carrying at least one wheel set, wherein the axial play of said at least one wheel set with respect to said at least one structure is adjustable along a pivot axis, such adjustment being possible by means of an axial play adjustment device or by means of a fitted case, said adjustment device including at least one pivot bearing for the wheel set, said at least one bearing defining, in the axial direction of the arbour, at least one axial stop for the wheel set, the adjustment device including at least one first smooth adjustment stage (adjustment stage) of variable thickness along the axial direction, the first adjustment stage including a first part provided with a pivoting drive which can be driven by a tool and which carries the bearing, and a second part onto which the first part is urged by at least one elastic return means, the second component is fixed to the structure directly or via at least one housing, wherein the elastic return means is supported on the structure directly or via at least one housing; said equipped casing comprising the adjustment means and comprising said casing housing at least one of said first adjustment stages, wherein the second component is fixed integrally with said casing and the elastic return means are supported inside said casing, characterized in that said at least one structure comprises a counterbore for receiving at least one of said first smooth adjustment stages, wherein the first component and the second component are guided into the bore of the counterbore, the second component is fixed directly to the structure and the elastic return means are supported on the bottom of the counterbore.

According to a particular feature of the invention, the elastic return means are supported on the structure via at least one of said housings, and the second component is fixed to said housing in a fixed position and in a fixed angular position along said axial direction.

According to a particular feature of the invention, the elastic return means comprise first indexing means (indexing means) for indexing the angular position of the elastic return means with respect to the casing, the casing comprising complementary first indexing means, and second indexing means for the angular positioning of the elastic return means with respect to the first component.

According to a feature of the invention, the first part comprises a first contact surface progressive along the axial direction according to an angular position and the second part comprises a second contact surface progressive along the axial direction according to an angular position, the second contact surface being in contact engagement with the first contact surface under the action of the elastic return means.

According to a particular feature of the invention, at least the first contact surface or the second contact surface comprises at least one annular helical cam path tangent to each radial line perpendicular to the axial direction over the entire width of the first contact surface or the second contact surface.

According to a particular feature of the invention, the first contact surface and the second contact surface each comprise at least one annular helical cam path tangent to each radial line perpendicular to the axial direction over the entire width of the first contact surface and the second contact surface.

According to a particular feature of the invention, the first contact surface and the second contact surface each comprise the same number of cam paths having the same angular amplitude and having the same cam pitch, and the first contact surface and the second contact surface are provided with complementary profiles.

The invention also concerns a timepiece including at least one movement of this type.

Drawings

Other features and advantages of the present invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:

fig. 1 shows a schematic perspective view of a micrometric axial play adjustment device for a timepiece wheel set according to the invention, made in the form of a first variant of an assembled casing, comprising means for axially adjusting the position of the bearing, which can be operated in the slot by a tool.

Fig. 2 shows a schematic exploded perspective view of the component parts of the assembled housing of fig. 1.

Fig. 3 shows a schematic perspective view of a first part comprising a first progressive contact surface formed by three helical cam segments.

Fig. 4 shows a schematic perspective view of a second part comprising a second progressive contact surface formed by three helical cam segments, complementary to the first contact surface of fig. 3.

Fig. 5 shows a schematic perspective view of at least one elastic return means, made in the form of a stamped spring that pushes the first part of fig. 3 onto the second part of fig. 4, which together form a first axial clearance adjustment stage.

Fig. 6 shows a schematic perspective view of a second variant of the assembled housing with two adjustment stages.

Fig. 7 shows a schematic exploded perspective view of the component parts of the assembled housing of fig. 6.

Fig. 8 shows a schematic cross-sectional view of the assembled housing of fig. 1 through the pivot axis of the wheel set.

Figure 9 shows a schematic cross-section through the pivot axis of the wheel set of a structure comprising a counterbore incorporating the bearing axial play adjustment device according to the invention.

Fig. 10 shows a partial view of an advantageous embodiment of the invention in a similar manner to fig. 8.

Fig. 11 shows, in block diagram form, a timepiece comprising a timepiece movement having a structure carrying a wheel set, the axial clearance of which with respect to the structure can be adjusted by means of a micrometric adjustment device according to the invention.

Detailed Description

The invention concerns the field of guiding and adjusting a timepiece wheel set.

The invention is described by way of example with respect to the adjustment of the axial play of a single pivot guide bearing for a wheel set. Of course, each pivot guide bearing of the wheel set may be equipped with a similar mechanism.

The invention also concerns a timepiece movement 100 comprising at least one structure 3 carrying at least one wheel set 2. The axial play of the at least one wheel set 2 relative to the at least one structure 3 is adjustable along the pivot axis D by the micrometric axial play adjustment device 1 or by the equipped housing 20.

The micrometric axial play adjustment device 1 comprises at least one pivot bearing 4 for the wheel set 2. The at least one bearing 4 defines at least one axial stop for the wheel set 2 in the axial direction D. The device 1 comprises at least one smooth adjustment stage 5 (i.e. without internal or external thread) with a variable thickness along the axial direction. The adjusting stage 5 comprises a first part 6 and a second part 8, the first part 6 being provided with a pivoting drive 7 which can be driven by means of a tool and which carries the bearing 4, and the first part 6 being pushed onto the second part 8 by at least one elastic return 9. The second component 8 is fixed to the structure 3 directly or by means of at least one housing 10. The elastic return means 9 are supported on the structure 3 directly or through at least one housing 10.

The equipped housing 20 comprises the device 1 and comprises the housing 10, the housing 10 accommodating at least one first adjusting stage 5, wherein the second part 8 is integrally fixed with the housing 10 and the elastic return device 9 is supported inside the housing 10.

According to the invention, said at least one structure 3 comprises a counterbore 30 for receiving at least one of said first smoothing stages 5, wherein the first component 6 and the second component 8 are guided into a bore 32 of the counterbore 30, the second component 8 is fixed directly to the structure 3, and the elastic return means 9 are supported on a bottom 31 of the counterbore 30.

The timepiece wheel set 2 thus pivots relative to the carrier structure 3 about the pivot axis D. Device 1 for micrometric axial clearance adjustment of wheel set 2 with respect to structure 3 comprises at least one pivot bearing 4 for wheel set 2. This bearing 4 defines, in the axial direction of axis D, at least one axial stop for wheel set 2. In a broad sense, "bearing" 4 refers to the function of the guide wheel set 2: guiding the actual pivoting, any axial support, any shock-resistant damper, the bearing 4 is made in one or more parts, in particular a single part made of silicon which can be made by the "Liga" or "MEMS" process, which combines radial guiding, axial support and damping.

According to the invention, the device 1 comprises at least one first regulation stage 5, which regulation stage 5 is smooth (without any internal or external thread) and has a variable thickness in the axial direction according to the relative regulation of the components comprised in the regulation stage, wherein said components are a first component 6 and a second component 8: said first part 6 is provided with a pivoting drive 7 drivable by means of a tool (screwdriver or wrench or the like) and carrying the bearing 4, said first part 6 being pushed onto said second part 8 by at least one elastic return means 9.

The second component 8 is fixed directly to the structure 3, as shown in the variant in fig. 9, or to the structure 3 via at least one housing 10, as shown in fig. 1, 2, 6 and 8. It is also conceivable to fix the component 8 via at least one further adjustment stage 50, as shown in fig. 6 and 7, with a variable thickness in the axial direction, provided that each adjustment stage can be locked in the angular direction.

The elastic return means 9 are supported directly on the structure 3, as shown in the variant in fig. 9, or on the structure 3 via at least one housing 10, as shown in fig. 1, 2 and 6-8.

In the case of fig. 1, 2 and 6-8, the elastic return means 9 are thus supported on the structure 3 via at least one housing 10, and the second component 8 is fixed on this housing 10 in a fixed position in the axial direction and in a fixed angular position.

In a particular embodiment, as shown in fig. 2, 5 and 9, the elastic return means 9 (which are in particular made in the form of a stamped spring) comprise first indexing means 91, for example peripheral jaws or notches, for the angular positioning of the elastic return means 9 with respect to the casing 10, the casing 10 comprising complementary first indexing means 11, for example notches or bosses. The elastic return means 9 also comprise second indicator means 92, such as lugs or notches, for the angular positioning of the elastic return means 9 with respect to the first part 6, which first part 6 comprises opposite complementary means (such as notches or lugs), which are not shown to avoid complicating the drawing.

In a preferred embodiment shown in the figures, the first part 6 comprises a first contact surface 16 that is progressive axially according to the angular position, and the second part 8 comprises a second contact surface 18 that is progressive axially according to the angular position. The second contact surface 18 is in contact engagement with the first contact surface 16 under the action of at least one elastic return means 9.

It will be appreciated that the contact surface corresponds to a particular height, depending on the relative angle formed by the first and second components 6, 8, and therefore the overall thickness of the conditioning stage 5 formed by stacking these two components is dependent on the angular offset between the two components. Advantageously, the contact surface is designed so that a given offset angle corresponds to a specific overall thickness value, which provides reproducibility and, if necessary, allows the visible face of the second component 8 to be graduated against the drive means 7 (here a straight radial slot) in order to indicate to the user the resulting change in axial clearance.

In a preferred variant shown in the figures, at least the first contact surface 16 or the second contact surface 18 comprises at least one annular helical cam path which is tangential, over the entire width of the contact surface, to each radial line perpendicular to the axial direction. The opposing contact surface may comprise a relief element such as another cam, a series of steps, or a series of projections or recesses, or the like. Furthermore, each contact surface can be made according to one of these examples, but a variant of the cam with a very small pitch is preferred by the invention, since it allows continuous adjustment, very small axial variations for large angular clearances and thus high sensitivity. In addition, a small cam slope ensures that there is sufficient friction to hold the cam in place. The friction provided by the elastic return means 9 achieves the same position holding function.

In the preferred variant shown in the figures, both the first contact surface 16 and the second contact surface 18 comprise at least one annular helical cam path which is tangential, over the entire width of the contact surfaces, to each radial line perpendicular to the axial direction.

More specifically, the first contact surface 16 and the second contact surface 18 both comprise the same number of cam paths (here three) having the same angular amplitude and the same cam pitch, and the first contact surface 16 and the second contact surface 18 are arranged in complementary profiles. These cams with a small slope also have a small thickness, which is advantageous for saving space and for integrating the axial play adjustment device 1 in a flat or ultra-flat movement.

Fig. 10 shows a detail of a particular embodiment, wherein the return means 9 is a stamped spring in the shape of a spherical dome, and wherein the first component 6 comprises a guide surface 62, which guide surface 62 cooperates with an opposite surface 102 of the housing 10 for radial guidance. The first part 6 further comprises a housing cavity 61, which housing cavity 61 is intended to receive a lug 92 of the spring 9 forming an indicator means 92 and to stop the rotation of this lug 92, wherein the housing cavity 61 forms a complementary indicator means.

The invention also makes it possible to combine several adjustment stages, for example in order to obtain a greater adjustment range, while allowing adjustment at values of several microns. In this case, the second component 8 is fixed to the structure 3 via at least one further adjusting stage 50 having a variable thickness in the axial direction. The composition of the further conditioning stage 50 is preferably similar to that of the first conditioning stage 5 and comprises: in one aspect, a third part 60 of the pivoting drive 70 is provided, which can be driven by a tool, the third part 60 being integral with the second part 8 and comprising a third contact surface 160 opposite the second contact surface 18; on the other hand, a fourth component 80 carrying a fourth contact surface 180 cooperating with the third contact surface 160, the fourth component 80 being fixed to the structure 3 directly or via at least one further adjustment stage. Fig. 6 and 7 show an assembly of this type comprising two adjustment stages 5 and 50 with concentric adjustment devices 7 and 70 accessible by the operator on the same side.

The invention also relates to an equipped housing 20 comprising a device 1 of this type. The housing 20 preferably comprises a housing 10 of this type, which housing 10 accommodates at least one of the first adjusting stages 5, wherein the second component 8 is integrally fixed with the housing 10 and the elastic return means 9 are supported inside the housing 10. The equipped housing 20 forms a complete micrometric adjustment device of small thickness, apt to be housed in a hole or counter-bore of the structure 3. The housing 20 forms a special convex part (cabochon) which integrates all or part of the functions of the bearing 4 and radial guidance, axial support and damping and has the advantage of providing axial adjustment in a space of similar dimensions almost no larger than conventional convex parts. Of course, the housing 10 may include an external shoulder for assembly in a smooth bore and supported on the face of a bedplate or clamping plate. The housing 10, when assembled into the counterbore of the structure, may have a cylindrical outer diameter and be driven or secured in place by any method known to watch makers.

The invention also concerns a timepiece movement 100 comprising at least one structure 3 carrying at least one wheel set 2. The axial play of the at least one wheel set 2 relative to the at least one structure 3 is adjustable by means of a micrometric adjustment device 1 or by means of the equipped housing 20.

In the embodiment shown in fig. 9, movement 100 comprises a structure 3, which structure 3 comprises a counterbore 30 for receiving at least one first regulation stage 5, which is free of internal and external threads. The first and second components 6, 8 of the regulation stage 5 are guided into the bore 32 of the counterbore 30, the second component 8 is directly fixed to the structure 3, and the elastic return means 9 are supported on the bottom 31 of the counterbore 30. In one particular embodiment as shown, the second member 8 includes a collar 81, the collar 81 being integrally secured with the shoulder 33 contained in the counterbore 30.

The invention also concerns a timepiece 200 including at least one such movement 100.

The use of equipped housings with different adjustment ranges allows the same size of external space to be adapted to multiple types of housings (with narrow or very wide adjustment ranges). The first and second parts and the housing can be made by a micro-injection moulding or "MEMS" type process and do not require any machining, whereas the springs forming the elastic return means are advantageously formed and cut by stamping. The only machining required is the machining of the structure for receiving the adjustment device according to the invention.

In short, the invention achieves the following objectives: high sensitivity, easy adjustment by common watchmakers, compactness and reduction of production costs. The invention makes it possible to easily modify an existing movement, i.e. to incorporate an axial play adjustment function and to achieve improved chronograph performance and thus improve a timepiece incorporating said movement, simply by machining a hole or counter bore in a plate or bridge.

Claims (10)

1. Timepiece movement (100) comprising at least one structure (3) carrying at least one wheel set (2), wherein the axial clearance of the at least one wheel set (2) relative to the at least one structure (3) along a pivot axis (D) can be adjusted by means of a micrometric axial clearance adjustment device (1) or by means of a housing (20) equipped, wherein the adjustment device (1) comprises at least one pivot bearing (4) of the wheel set (2), the at least one bearing (4) defining, in the axial direction of the axis (D), at least one axial stop for the wheel set (2), the adjustment device (1) comprising at least one smooth first adjustment stage (5) having a variable thickness in the axial direction, the first adjustment stage (5) comprising a first part (6) and a second part (8), the first part (6) is provided with a pivoting drive (7) which can be driven by means of a tool and which carries the bearing (4), and the first part (6) is pushed onto the second part (8) by at least one elastic return device (9), the second part (8) being fixed to the structure (3) by at least one housing (10), wherein the elastic return device (9) is supported on the structure (3) via at least one housing (10); the equipped housing (20) comprises the adjusting device (1) and comprises the housing (10) accommodating at least one first adjusting stage (5), wherein the second component (8) is fixed integrally with the housing (10) and the elastic return device (9) is supported inside the housing (10), the movement (100) being characterized in that the at least one structure (3) comprises a counterbore (30) for receiving at least one smooth first adjusting stage (5), wherein the first component (6) and the second component (8) are guided into a bore (32) of the counterbore (30).

2. Timepiece movement (100) according to claim 1, wherein the elastic return means (9) are supported on the structure (3) via at least one of the housings (10), and the second component (8) is fixed on the housing (10) in a fixed position and in a fixed angular position along the axial direction.

3. Timepiece movement (100) according to claim 2, wherein the elastic return means (9) comprise first indexing means (91) for indexing the angular position of the elastic return means with respect to the case (10), the case (10) comprising complementary first indexing means (11), the elastic return means (9) further comprising second indexing means (92) for the angular positioning of the elastic return means with respect to the first component (6).

4. Timepiece movement (100) according to claim 1, wherein the first part (6) comprises a first contact surface (16) progressive along the axial direction according to an angular position, and the second part (8) comprises a second contact surface (18) progressive along the axial direction according to an angular position, the second contact surface (18) being in contact engagement with the first contact surface (16) under the action of the elastic return means (9).

5. A timepiece movement (100) according to claim 4, wherein at least the first contact surface (16) or the second contact surface (18) includes at least one annular helical cam path which is tangent to each radial line perpendicular to the axial direction over the entire width of the first contact surface or the second contact surface.

6. A timepiece movement (100) according to claim 5, wherein the first contact surface (16) and the second contact surface (18) each include at least one annular helical cam path that is tangent to each radial line perpendicular to the axial direction over the entire width of the first contact surface and the second contact surface.

7. Timepiece movement (100) according to claim 6, wherein the first contact surface (16) and the second contact surface (18) each comprise the same number of cam paths having the same angular amplitude and the same cam pitch, and the first contact surface (16) and the second contact surface (18) are provided in complementary profiles.

8. Timepiece movement (100) according to claim 4, wherein the second component (8) is fixed to the structure (3) via at least one smooth further adjustment stage (50) having a variable thickness in the axial direction, the further adjustment stage (50) comprising a third component (60) and a fourth component (80), wherein the third component (60) is provided with a pivoting drive means (70) drivable by a tool, the third component (60) being integral with the second component (8) and comprising a third contact surface (160) opposite the second contact surface (18); the third part (60) is pushed by at least one elastic return means (9) onto the fourth part (80), the fourth part (80) carrying a fourth contact surface (180) cooperating with the third contact surface (160), the fourth part (80) being fixed to the structure (3) directly or via at least one other adjustment stage.

9. Timepiece movement (100) according to claim 1, wherein the second component (8) comprises a collar (81), the collar (81) being fixed integrally with a shoulder (33) contained in the counterbore (30).

10. A timepiece (200) including at least one timepiece movement (100) according to claim 1.