EP2795408A1

EP2795408A1 - Method for improving the pivotal movement of a mobile body

Info

Publication number: EP2795408A1
Application number: EP12791818.3A
Authority: EP
Inventors: Thierry Conus; Marco Verardo; Ivan Villar; Andrés Cabezas Jurin; Jean-Luc Helfer; Emmanuel Graf
Original assignee: Swatch Group Research and Development SA
Current assignee: Swatch Group Research and Development SA
Priority date: 2011-12-22
Filing date: 2012-11-30
Publication date: 2014-10-29
Anticipated expiration: 2032-11-30
Also published as: US20150198927A1; JP5820542B2; CN104169814A; EP2795408B1; EP2795409B1; HK1204497A1; CN104169814B; US9645551B2; RU2573701C1; JP2015508492A; JP5820543B2; WO2013092173A1; CN104011609B; WO2013092172A1; JP2015511307A; EP2795409A1; EP3376306A1; US9310774B2; RU2573811C1; US20140355397A1

Abstract

The invention relates to a method for improving the pivotal movement of a mobile body (1) for a scientific instrument, comprising a shaft (10) capable of pivoting or oscillating about an axis (D) of the mobile body, wherein said method comprises: statically balancing said mobile body so as to bring the center of gravity thereof onto said axis (D); determining a target value for the resulting imbalance moment of said mobile body about said axis (D), which corresponds to a predetermined target divergence between a first main longitudinal axis of inertia of said mobile body and said axis (D); rotating said mobile body about said axis (D) of the mobile body at a predetermined speed, and measuring the resulting imbalance moment relative to said axis (D); and adjusting the value of the imbalance moment of said mobile body about said axis (D) to within a given predetermined tolerance relative to said target value.

Description

Method for improving the pivoting of a mobile

Field of the invention

The invention relates to a method for improving the pivoting of a mobile or a mobile equipped for scientific instrument or timepiece, comprising at least one shaft arranged to pivot or oscillate about an axis of oscillation aligned with a mobile axis constituted by the axis of said shaft.

The invention also relates to a mobile for scientific instrument or timepiece, comprising at least one shaft arranged to pivot or oscillate about an axis of oscillation aligned on a mobile axis constituted by the axis of said shaft, and comprising less a flange connected to said movable shaft and protruding radially from said shaft, said flange being substantially perpendicular to said axis of moving.

The invention also relates to a mobile equipped for scientific instrument or timepiece comprising such a mobile.

The invention also relates to a mechanism for scientific instrument or timepiece comprising such a mobile equipped and / or such a mobile.

The invention also relates to a scientific instrument comprising such a mechanism and / or such a mobile equipped and / or such a mobile.

The invention relates to the field of precision mechanics, in particular mechanical scientific equipment, and in particular the fields of meters and precision devices comprising mechanisms for measuring, displaying or comparing a flow rate, consumption, or time, comprising components movable pivotally or oscillating about an axis.

Background of the invention

In the field of mechanical precision devices, the quality of the guides of certain components moving in rotation or oscillation about an axis is of great importance, for the reproducibility over time of the measurements made or the signals generated. Any fault at the level of the guides, between pivots of the mechanism on the one hand and on the other hand of the staves, that includes a component tree, results in poor accuracy, but also wear and degradation of performance over time. The geometric quality of the machining is a necessary condition for precision operation, but this condition is often not sufficient. Indeed, the vibration behavior, in particular in the presence of unbalance, directly influences the pressures exerted on the bearings, and therefore the lubrication constraints, and the maintenance constraints especially in case of replacement or rebuilding bearings or / and pivots to restore the quality of the guides after wear.

Static balancing of the components, bringing their center of mass back to the pivot or oscillation axis, improves the situation and makes it possible to delay wear. However, the effects induced by the inertia defects induce significant disturbances on the operation of the mechanism, and the service life in time. Summary of the invention

The invention proposes to provide a solution to ensure a reduction of friction in the guides of the rotating components of such precision mechanisms, and to improve the accuracy of operation of these mechanisms. It also seeks to allow an increase in rotation speeds and / or oscillation frequencies of the components concerned.

The search for a better precision leads to seek a better setting of the mobile, in particular by the execution of a dynamic balancing of quality.

Also the invention proposes to balance the mobile dynamically, that is to say, to bring its main axis of inertia on the axis of rotation.

To this end, the invention relates to a method for improving the pivoting of a mobile or a mobile equipped for scientific instrument or timepiece, comprising at least one shaft arranged to pivot or oscillate about an axis of oscillation aligned on a mobile axis constituted by the axis of said shaft, characterized in that:

- Static balancing of said mobile to bring its center of gravity on said mobile axis; a target unbalance moment value resulting from said moving body is determined around said mobile axis, corresponding to a predetermined target divergence between a first principal axis of longitudinal inertia of said mobile, and said axis of the mobile;

said mobile is rotated at a predetermined speed about said mobile axis, and its resulting unbalance moment is measured with respect to said mobile axis;

- An adjustment of the value of the unbalance moment resulting from said mobile about said mobile axis in a given given tolerance with respect to said target value.

According to another characteristic of the invention, said adjustment is made by adding or / and displacement or / and removal of asymmetrical material with respect to a plane defined by the other two main axes of inertia of said mobile or equipped mobile.

The invention also relates to a mobile for scientific instrument or timepiece, comprising at least one shaft arranged to pivot or oscillate about an axis of oscillation aligned on a mobile axis constituted by the axis of said shaft, and comprising less a flange connected to said movable shaft and protruding radially from said shaft, said flange being substantially perpendicular to said axis of moving, characterized in that it comprises, of manufacture, a first main axis of longitudinal inertia adjacent to said axis of mobile or confused with it, and two other main axes of inertia together defining a median plane, and in that said flange comprises a plurality of housings each receiving a movable mass adjustable in position in said housing concerned, or only in a parallel direction said axis of mobile, or only in a plane perpendicular to a radial end of said mobile axis.

According to a feature of the invention, said median plane is located in the thickness of said flange.

The invention also relates to a mobile equipped for scientific instrument or timepiece comprising such a mobile, characterized in that it further comprises a drive means, or / and a means of recall or elastic repulsion, and / or a means of return or magnetic repulsion, or / and a means of return or repulsion electrostatic. The invention also relates to a mechanism for scientific instrument or timepiece comprising such a mobile equipped and / or such a mobile.

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 appended drawings, in which:

- Figure 1 shows, schematically and in longitudinal section, an example of mobile equipped according to the invention;

- Figure 2 shows, schematically and in section along a plane passing through the axis of the mobile, different machining variants 2A to 2F achievable for the implementation of the static and dynamic balancing method according to the invention;

- Figures 3 to 1 1 show, schematically and partially, other mobile variants according to the invention:

- Figure 3A in perspective with breakable weights and / or pliable distributed on either side of a median plane of a flange of the mobile, as shown in Figure 3B in section along a plane passing through the axis mobile;

FIG. 4A, in plan view, and FIG. 4B, in section, with movable masses on or under rails incorporated in windows of a flange of the mobile,

- Figure 5, in section, with a deformable blade with a component in the axial direction of the mobile, the deformation of each blade being printed by a set screw;

- Figure 6 with a mass orientable angularly with respect to a window that includes a flange of the mobile, and having an arc resting on a first edge and under a second edge of this window;

- Figure 7 with adjusting screws in a flange of the mobile, mounted parallel to the axial direction of the mobile;

- Figure 8 with screws similar to those of Figure 7, arranged alternately on and under a flange of the mobile; - Figure 9 with adjusting screws in the thickness of a flange of the mobile, mounted in the median plane of the flange in radial directions relative to the axis of mobile, these screws having heads which are not of revolution, but which are symmetrical with respect to the axis of screwing;

- Figure 10 similar to Figure 9, but with screws whose head is asymmetrical with respect to the axis of screwing;

- Figure 1 1 with a flange having a peripheral portion connected to an axial core by fasteners, the peripheral portion being slotted and deformable at the different portions thereof, each carried by one of these fasteners;

FIG. 12 is a diagrammatic sectional view along a plane passing through the axis of the mobile, a smooth mass adjustable in axial position in a housing, FIG. 13 is a grooved mass, and FIG. mass trapped relative to a flange of the mobile.

FIG. 15 schematically and schematically shows a scientific instrument comprising a mechanism with a mobile equipped according to the invention;

FIGS. 16A and 16B show, in end and side view, a pre-realization of a mobile with a moment of impending unbalance imposed or forced.

Detailed Description of the Preferred Embodiments

The invention relates to the field of mechanical scientific equipment, and in particular to the fields of meters and precision devices comprising measurement or time comparison mechanisms, comprising components that are pivotally or oscillating about an axis .

More particularly, the invention is concerned with the optimal balancing of a mobile 1 or a mobile equipped 40.

By "mobile" is meant, in the following description, any tree component movable pivoting or oscillation about a so-called mobile axis D, corresponding to the axis of the tree portion. This mobile may, if necessary, but not necessarily, have teeth, gears, other drive means such as grooves or bearings, as well as fastening or cooperation elements with a driving means, and / or elastic return or repulsion means, and / or magnetic return or repulsion means, and / or an electrostatic booster or repulsion means, or the like. Here is called "mobile equipped" 40 a subset or a mechanical assembly comprising at least one such mobile 1, and all or part of a drive means, and / or a means of return or elastic repulsion, or / and a magnetic return or repulsion means, and / or an electrostatic booster or repulsion means, or the like. FIG. 1 illustrates a nonlimiting example of such an equipped mobile 40, consisting on the one hand of a mobile 1, and on the other hand of magnetic repulsion means 41. The mobile 1 comprises a shaft 10 of axis D, in this example a toothed wheel 42 and a pinion 43, and a flange 2 carrying adjustment means 4, here represented in a radial implantation in a radial direction R to the axis D and in a so-called median plane P corresponding to the theoretical secondary axes of inertia, the theoretical principal axis of inertia coinciding with the axis D.

The term "flange" a projecting portion substantially radially, preferably of revolution about the axis of the mobile, and of diameter greater than that of the shaft. The same mobile can naturally include several such flanges, some of which may have particular functions, such as gears, pulleys, or the like.

The invention proposes to dynamically balance the mobile 1, or the mobile equipped 40. that is to say, to bring its main axis of inertia on the axis of rotation. The various embodiments, non-limiting, and the figures illustrate the application of the invention to a mobile 1 naked, and are naturally applicable to a mobile equipped 40.

In addition to this search for a perfect balance, it is also possible to create a controlled imbalance, that is to say to incline the principal axis of inertia of the mobile of a certain angle in a certain direction, relative to :

- to the axis of the mobile;

- A plane passing through this mobile axis and materialized by a functional reference, particularly preferably an angular reference of the mobile.

For this, two steps are necessary:

- measure dynamic imbalance - correct this imbalance, either to cancel it or to bring it to a well-defined value.

To this end, the invention relates to a method of improving the pivoting of a mobile 1 or a mobile 40 equipped for scientific instrument or timepiece. This mobile 1 comprises at least one shaft 10 arranged to pivot or oscillate about an axis of oscillation aligned on a mobile axis D constituted by the axis of this shaft 10, and preferably at least one flange 2 of space diametrical to that of the shaft 10. In the case where the mobile is reduced to the shaft 10 alone, it remains possible to perform a dynamic balancing using certain implementation variants of the invention, applicable to such a device. tree ; only the variants, described below, which require components bearing on either side of a web of low thickness, and which are difficult to implement on a substantially cylindrical arbaceous part, will instead be reserved for mobile having a flange substantially flat and substantially perpendicular to the axis of mobile.

This mobile 1 or mobile equipped 40 is arranged to oscillate about an axis of oscillation aligned on this axis of mobile D.

According to the invention:

static balancing is performed on this mobile or mobile equipped to bring its center of gravity onto the mobile axis D;

a target unbalance moment value is determined, describing its dynamic unbalance, of the mobile or mobile equipped around the mobile axis, corresponding to a target divergence, in particular in certain applications a target divergence, predetermined between a first main axis; longitudinal inertia of the mobile, and the axis of the mobile D;

this mobile or mobile equipped around the mobile axis D is rotated at a predetermined speed, and its resulting unbalance moment with respect to the mobile axis D is measured with at least one measurement;

- An adjustment is made of the value of the unbalance moment resulting from the mobile around the axis of mobile in a given determined tolerance with respect to the target value. The effect of this adjustment is to bring the first main axis of longitudinal inertia on the one hand, of the mobile axis on the other hand, below the predetermined target divergence. In a particular application, the predetermined tolerance range comprises an upper bound corresponding to the target value. In other applications, the tolerance range is around this target value.

Preferably, said target unbalance moment target value is determined in the form of a maximum allowable unbalance moment value resulting from the mobile or mobile equipped around the mobile axis, this maximum value corresponding to a predetermined maximum angular divergence between a first main axis of longitudinal inertia of the mobile or mobile equipped on the one hand, and the axis of the mobile on the other hand. The adjustment of the value of the dynamic balancing moment of the mobile or equipped mobile then has the effect of bringing the first main axis of longitudinal inertia of the mobile axis, below the predetermined maximum angular divergence.

In a particular embodiment of the invention, this adjustment is made by adding or / and displacement or / and removal of asymmetrical material with respect to a plane defined by the other two main axes of inertia of the mobile or mobile equipped .

In a particular embodiment, an addition is made and / or displacement and / or removal of material at the level of at least one flange that includes the mobile, protruding radially relative to its shaft.

In a particular embodiment, an addition is made and / or displacement or / and removal of material at the shaft of the mobile.

In a particular embodiment, an addition is made and / or displacement or / and removal of material at least one arm that includes said mobile between said shaft and another eccentric portion of said mobile.

In a particular mode of implementation of the invention, the static balancing is performed before adjusting the value of the dynamic balancing moment.

In another particular mode of implementation of the invention, this static balancing is performed simultaneously with the adjustment of the value of the dynamic balancing moment.

In a particular mode of implementation of the invention, this maximum value of unbalance moment resulting from the moving part is set to zero. mobile equipped around the axis of mobile, so as to coincide the first main axis of longitudinal inertia of the mobile or mobile equipped with the axis of the mobile.

In a particular embodiment of the invention for an oscillating mobile, this predetermined speed of rotation is fixed at the maximum calculated angular velocity for the mobile or equipped mobile, considered during its oscillation in service.

In a particular mode of implementation of the invention, prior to this static balancing and dynamic balancing, at the level of a flange 2, when the mobile has one, cylindrical or corrugated housings arranged to receive are machined. cylindrical or fluted masses movable in an axial direction parallel to the axis of mobile. And then performs all or part of the adjustment by displacement of such moving masses inserted in some of these housing, relative to the plane defined by the other two main axes of inertia of the mobile or equipped mobile. In the absence of flange, the machining of such housing on the shaft 10 of the mobile.

In a particular embodiment of the invention, prior to this static balancing and dynamic balancing, these mobile masses are made trapped and unmountable with respect to the flange, either during a one-piece execution of the mobile or mobile equipped together with these moving masses, or by expansion of at least one end of each movable mass to prevent the passage of the expanded zone through the housing corresponding to this mobile mass.

In a particular embodiment of the invention, all or part of the adjustment by deformation of a flange 2, which comprises the mobile or mobile equipped, asymmetrically with respect to the plane defined by the other two main axes of inertia of the mobile or equipped mobile.

In a particular embodiment of the invention, prior to static balancing and dynamic balancing, a flange 2, which comprises the mobile or mobile equipped with radial threaded housings arranged to receive screws, is machined before static balancing and dynamic balancing. asymmetrically movable head in a radial direction relative to the axis of mobil, and all or part of said adjustment is effected by moving such screws screwed into some of these threaded housing. In the absence of a flange, machining of such tapped housings on the shaft 10 of the mobile. In a particular embodiment of the invention, when a measure of unbalance moment resulting from the mobile or mobile equipped with respect to the axis of mobile, the imbalance in angular position is noted with respect to a reference mark. angular that includes the mobile or mobile equipped, such as a pin, a notch, a drilling, a reported component, a marking, or the like.

In a particular mode of implementation of the invention, prior to this static balancing and dynamic balancing, a flange, which comprises the mobile or mobile equipped, with a mal-dish of a predetermined value, is machined. In particular, in a particular embodiment, an unbalance or / and a moment of unbalance resulting in a particular angular direction is created voluntarily, and offset with respect to the median plane P. FIGS. 16A and 16B thus illustrate thicknesses 31 and 32, on either side of the plane P, and together substantially defining a plane PS passing through the axis of the mobile D. Thus a large controlled unbalance is created, which makes it easier to fine unbalance corrections for static balancing and dynamic balancing. This forces the correction in a certain zone around this plane PS passing through the axis D.

To perform the imbalance correction, it is advantageous to use the following nonlimiting methods, combinable with each other, and applicable at the level of a flange 2 or the shaft 10 of the mobile, or the connecting arm between the shaft and a peripheral mass, or at such peripheral masses:

- removal of material: machining by milling or turning or abrasion or the like, laser ablation or microlaser or nanolaser or picolaser or femtolaser, breakage of breakable elements held by fragile fasteners;

- addition of material: liquid projection for solid solidification on the mobile, especially by inkjet or the like, solid objects reported in a fixed position;

material displacement: objects with adjustable position, displacement of at least one flange portion by twisting of the flange or a part of the moving part, or an arm, displacement of a flexible blade, displacement of screw or smooth or fluted or facetted inserts, these screws or inserts can advantageously be asymmetrical with respect to their direction of insertion or screwing. The figures show, in a nonlimiting manner, adjustments made on a flange of mobile, since it is easier to make an inertia correction near the largest diameter of the mobile, allowing to make only corrections minimal mass. To simplify the representation, only this flange is illustrated, without complete representation of the mobile tree. Naturally, the arrangements described are also applicable to other forms of mobile, and machining or adjustment components can be positioned on other parts of the mobile, depending on their accessibility.

As regards more particularly the removal of material, FIGS. 2A to 2F illustrate different variants of balancing machining performed on a flange 2 of mobile 1, FIG. 2F illustrating in particular a balancing machining hidden at the bottom of a throat for aesthetic reasons.

Advantageously, when, preferably, the main axis of theoretical inertia is constituted by the axis D of the mobile, and the median plane P is calculated to include the two secondary axes of inertia, the machining is performed from and others of this plane P. The non-limiting figures illustrate different possibilities: on either side of the median plane (FIGS. 2A, 2C, 2D, 2E), internal / external machining with respect to the flange (FIGS. 2C , 2D), volume and radial positioning different from the axis of the mobile (Figure 2B), machining performed axially from the same side of the flange (2B, 2E) or from the opposite sides (Figure 2A).

Naturally, the distribution possibilities are similar as regards the addition or the displacement of matter.

FIGS. 3A and 3B illustrate a mobile device 1 comprising breakable and / or collapsible weights 6, 6A and 6B distributed on either side of a median plane P of the flange 2. The breaking of a thin fastener 6C makes it possible to obtain a differential of inertia with respect to the axis D, and the large number of weights 6, of the order of thirty per level in the example of the figure, allows an adjustment with respect to the direction of the moment resulting unbalance measured.

FIG. 11 illustrates a flange 2 comprising a peripheral portion 2B connected to an axial core 2A by fasteners 23A, 23B, 23C, 23D, this peripheral portion 2B being slotted by slots 20, and deformable at the various portions 19A, 19B, 19C, 19D it includes, each worn by one of these fasteners. Preferably, plastic deformation of all or part of the fasteners 23A, 23B, 23C, 23D is performed to straighten or otherwise wave the flange 2. Thus, for example, a fastener 23A carries a sector-shaped section 19A whose ends 21 A and 22A are movable relative to the radial direction R of the fastener considered, here 23A, and, by twisting of this fastener, the two ends are spaced apart on either side of the median plane of the flange at rest. Each fastener 23A, 23B, 23C, 23D may be deformed independently of the others. In another variant embodiment, the fastener may be rigid, and the sector of flange deformable. In another variant, they can both be deformable, however the measurement is less easy, especially in case of reverse setting.

Figures 1, 4 to 10, and 12 to 14 illustrate mobile variants with reported components.

Figure 12 shows a smooth mass 26 adjustable in axial position in a housing 25, in a direction A parallel to the axis of mobile D. Figure 13 shows a fluted mass 27 movable in an ad hoc housing. FIG. 14 shows a prisoner mass relative to the flange 2 of the mobile 1, with a head 28 on one side of the flange 2, and a rivet 29 or a bubble expansion on the other side of the flange 2. The displacement according to FIG. the direction A allows adjustment in dynamic balancing, the smooth masses 26 or fluted 27 can, again, be graduated or notched in the direction A to facilitate adjustment, according to a calculation by a control means of the dynamic balancing process.

FIG. 7 shows adjustment screws 14 in housings 15 of the flange 2, mounted parallel in a direction A to the axial direction D of the mobile 1. Figure 8 comprises adjusting screws 14 similar to those of Figure 7, arranged alternately on (screw 14A) and under (screw 14B) the flange 2 of the mobile 1, in corresponding housings 15A and 15B. Naturally, the reverse mounting, with a nut on a threaded shaft, is also suitable. In either case, it is advantageous to use slightly different steps between the male component and the female component to improve the service life.

An attached component is advantageously mounted movably on the structure of the mobile. For this purpose, the mobile 1 comprises, slidably movable, a portion driven, or clipped, or mounted with clearance, either in rotation or axially. Providing at least one nip guide surface or the like allows the reported component to take discrete positions.

The mobility of the reported component can still be performed by screwing / unscrewing.

A setting component can thus be mounted with clearance, and tightened by a screw, for example sliding. Thus, FIGS. 4A and 4B illustrate mobile masses on or under rails 3 incorporated in windows of a flange 2 of mobile 1. These movable masses are constituted in particular by sliding stirrups 8 each comprising an immobilizing screw 7, here represented in a direction A axial parallel to the axis D of the mobile 1. The screw 7, and especially the head of this screw, can be placed on one side or the other of the mobile 1. Or it is the entire stirrup 8, equipped with its screw 7, which is placed on a rail 3 so as to present the head of the screw 7 on one side or the other of the mobile 1.

The adjustment component can also be clipped on an arm 3 or on the flange 2 of the mobile 1. For example, it may consist of a flexible object clipped on a rigid part, for example a flyweight on an axis, or a rigid object clipped into a flexible part, for example an axis in a slot.

An adjusting component may also be an additional component simply bonded, welded, or riveted to the structure of the mobile.

In an alternative embodiment, it bends a flexible insert.

FIG. 5 illustrates, in a first variant, a mobile 1 with at least one deformable blade 9, with a component in the axial direction A parallel to the axis D of the mobile. The deformation of each blade 9 is printed by a set screw 7, here shown fixed in a threaded housing 7A of the rail 3. In a variant not shown, such screws can also be carried by the flange 2. Advantageously at least one blade Flexible 9 equips each side of the mobile 1. The differential adjustment of inertia is provided both by the displacement of each adjusting screw 7 according to its direction A, and by the deformation of the corresponding flexible blade 9. Preferably, as shown in the figure, the flexible blade 9 is held at one end 9E, near the axis of the mobile 1, and is free at its other end, which it advantageously comprises an additional mass 9A. It is understood that the deformable blade 9 can be designed for use in a field of elastic deformation, in the optics of setting resets, or in the field of plastic deformation, in case of unique adjustment of the mobile. If the example of the figure illustrates a deformation of the flexible blade by a screw, the deformation controlled by the mechanism of a nut, or another mobile or deformable component, is naturally conceivable.

A second variant of this adjustment by bending implements a displacement of the fixing of the flexible part, possibly provided with notches, and with a support of the flexible part against a cam or a fixed zone.

Thus, FIG. 6 illustrates a mass 130 orientable angularly with respect to a window 2F that comprises a flange 2 of the mobile 1, and comprising an arc 13 resting on a first edge 2H and under a second edge 2G of this window 2F. The mass 130 is angularly adjustable relative to the flange 3, at an angle to the center a. This orientable mass 130 comprises a bearing washer 1 1 bearing on a bearing surface of the mobile 1, in particular a bearing surface of the shaft 10. This bearing washer 1 1 is integral with an arm 12, preferably flexible, which is itself secured to the arc 13, preferably of greater rigidity in torsion than that of the arm 12. This arc 13 bears, at a first end 13A on a first edge 2H, and at a second end 13B under a second edge 2G of this window 2F. The pivoting imposed on the orientable mass 13 forces it to take a particular twisting which makes it possible to modify the dynamic balancing of the mobile 1. In another embodiment, the arm 12 is rigid, and the bow 13 deformable. In another variant, they can both be deformable, however the measurement is less easy, especially in case of reverse setting.

To avoid introducing an unbalance, it is possible to use reported components with fixed position in projection in the median plane P, and movable in an axial direction A parallel to the axis D of the mobile 1. This is particularly the case of the embodiments of Figures 7 and 8, wherein the projection on the plane P of the center of inertia of each adjusting component or screw 14 remains stationary when moving the adjustment component.

In a particular arrangement, the adjustment components are installed in symmetry two by two with respect to the axis D of the mobile 1. Thus, symmetrical adjustments of the components of such a pair do not alter the static balancing of the mobile.

If necessary, each adjustment component is movable independently of the others.

Figures 9 and 10 illustrate two cases of application. In a first case, the center of inertia of the adjustment component is located on the axis of rotation of this component, and / or this component is in translation along an axis. If the center of inertia moves along the axis for example during a screwing, and if the projection on the median plane P of the center of inertia of the component also moves, then one must carry out the symmetrical displacement of the object opposite. Otherwise, each adjustment component is movable independently.

FIG. 9 illustrates this configuration, with a mobile 1 comprising adjusting screws 16 mounted in housings 17 in the flange 2, preferably mounted in the median plane P of the flange 2 in radial directions R with respect to the axis D of mobile. These adjusting screws 12 comprise heads which are not of revolution, but which are symmetrical with respect to the screw axis R, and whose angular position of the wings 16A and 16B makes it possible to modify the dynamic balancing. In the preferred embodiment of Figure 9 for this configuration, the screw head takes the form of a bar. The projection of this bar on a plane tangent to the flange 2 is at an angle β comparable to a helix angle. Thus, the wings 16A, 16B are either both in the same plane P in a single angular position where β = 0 or on either side of this plane P for the other values of the angle β.

In a second case, the center of inertia of the adjustment component is located outside the axis of rotation of the component. It is then systematically necessary to perform a symmetrical rotation of the opposite component of the pair.

This is the case of FIG. 10, where the mobile 1 comprises asymmetric adjustment screws 18 whose head is asymmetrical with respect to the screw axis, and comprises a wing 18B with a moment of inertia greater than that of the other wing 18A relative to the radial screw axis R. In the same way as in the previous case, the screw head takes the form of a bar. The projection of this bar on a plane tangent to the flange 2 is at an angle γ comparable to a helix angle, and we see in the figure that the components are oriented in pairs symmetrically with respect to their respective radial axis R .

The invention also relates to a mobile 1 for a scientific instrument or timepiece, comprising at least one flange 2 connected, either directly or by at least one arm, to a mobile shaft 10 aligned on a mobile axis D. This flange 2 is preferably substantially perpendicular to the mobile axis D. This mobile 1 is arranged to oscillate about an axis of oscillation aligned on this mobile axis D. According to the invention, this mobile 1 comprises, of manufacture, a first main axis of longitudinal inertia adjacent to this axis of mobile D or coincident with it, and two other main axes of inertia together defining a median plane P. In a particular embodiment, this median plane P is located in the thickness of the flange 2.

And this flange 2 comprises a plurality of housings each receiving a movable mass adjustable in position in the housing concerned, or only in a direction A parallel to the axis of mobile, or only in a plane perpendicular to a radial R from the mobile axis D.

In a particular mode of implementation of the invention, each such housing or / and each such corresponding mobile mass includes stop means for allowing the maintenance of this mobile mass in several discrete positions where its center of gravity is distant from this median plane P.

In a particular embodiment of the invention, each such housing or / and each such moving mass comprises resilient return means for holding in position this mobile mass in this housing.

The invention also relates to a mobile 40 equipped for scientific instrument or timepiece comprising at least one such mobile 1, and further comprises at least one drive means, and / or elastic biasing or repulsion means, and / or magnetic return or repulsion means, or / and a means of return or electrostatic repulsion, attached to the at least one mobile.

The invention also relates to a mechanism 50 for a scientific instrument or timepiece comprising such a mobile equipped 40 or / and such a mobile 1.

The invention also relates to a scientific instrument 60 comprising such a mechanism 50 or / and such a mobile equipped 40 or / and such a mobile 1.

In a particular application, this scientific instrument 60 is a watch, which comprises a movement 50, and the mobile 1 is a pendulum whose flange 2 is constituted by a disc or a serge, the equipped mobile 40 is a balance-spiral.

The invention allows a significant reduction of the forces on the pivots, a facilitated lubrication, and an increase in the lifetime of the mechanisms, and especially the useful life, that is to say the period during which the mechanism provides a reproducible response to an identical solicitation in from a power source, or signal, or other mechanism or sensor, or the like. The invention makes it possible to improve the stability of the movement of a mobile thus dynamically balanced.

Claims

REVE NDI CATI ONS

1. A method of improving the pivoting of a mobile (1) or a mobile equipped (40) for scientific instrument or timepiece, comprising at least one shaft (10) arranged to pivot or oscillate about an axis of oscillation aligned with a mobile axis (D) constituted by the axis of said shaft (10), characterized in that:

- Static balancing of said mobile to bring its center of gravity on said mobile axis (D);

determining a target unbalance moment value resulting from said mobile about said mobile axis (D), corresponding to a predetermined target divergence between a first principal axis of longitudinal inertia of said mobile, and said axis of the mobile (D);

said mobile is rotated at a predetermined speed about said mobile axis (D), and its resulting unbalance moment is measured with respect to said mobile axis (D);

- An adjustment of the value of the unbalance moment resulting from said mobile about said mobile axis (D) in a given specific tolerance with respect to said target value.

2. Method according to claim 1, characterized in that said adjustment is made by addition and / or displacement and / or removal of asymmetrical material with respect to a plane perpendicular to said mobile axis (D) of said mobile (1) or mobile equipped (40).

3. Method according to claim 1, characterized in that said adjustment is made by adding or / and displacement or / and removal of asymmetrical material with respect to a plane defined by the two other main axes of inertia of said mobile (1) or mobile equipped (40).

4. Method according to claim 2 or 3, characterized in that an addition is made and / or displacement and / or removal of material at at least one flange (2) that includes said mobile (1) radially projecting relative to said shaft 10).

5. Method according to claim 2 or 3, characterized in that an addition is made and / or displacement and / or removal of material at said shaft (10) of said mobile (1).

6. Method according to claim 2 or 3, characterized in that an addition is made and / or displacement and / or removal of material at least one arm that comprises said mobile between said shaft (10) and another eccentric part of said mobile.

7. Method according to one of claims 1 to 6, characterized in that performs said static balancing before making said adjustment of the value of the dynamic balancing moment.

8. Method according to one of claims 1 to 6, characterized in that said static balancing is carried out simultaneously with said adjustment of the value of the dynamic balancing moment.

9. Method according to one of the preceding claims, characterized in that sets at said zero value said unbalance moment target value resulting from said mobile or mobile equipped around said axis of mobile (D), so as to coincide said first main axis of longitudinal inertia of said mobile or mobile equipped with said axis of the mobile (D).

10. Method according to one of the preceding claims, characterized in that said predetermined speed of rotation is fixed at a maximum calculated angular velocity for said mobile or equipped mobile considered during its pivoting or oscillation in use in combination with at least drive means, or / and elastic return or repulsion means, and / or magnetic return or repulsion means, and / or a particular electrostatic booster or repulsion means.

11. Method according to one of the preceding claims, characterized in that factory, prior to said static balancing and dynamic balancing, at least one flange (2), which comprises said mobile (1) or mobile equipped (40), housing (25) cylindrical or grooved arranged to receive cylindrical movable masses (26) or fluted (27) movable in an axial direction (A) parallel to said movable axis (D), and all or part of said displacement adjustment is carried out said moving masses inserted in said housings relative said plane (P) defined by the two other main axes of inertia of said mobile (1) or mobile equipped (40).

12. Method according to the preceding claim, characterized in that prior to said static balancing and dynamic balancing, said movable masses (26; 27) are made captive and unmountable with respect to said flange (2), or during a one-piece execution. said mobile or mobile equipped together with said moving masses, or by expansion of at least one end of each said moving mass (26; 27) to prevent the passage of the expanded zone through said housing (25) corresponding to said moving mass (26; 27).

13. Method according to one of the preceding claims, characterized in that all or part of said adjustment by deformation of at least one flange (2), that includes said mobile (1) or mobile equipped (40), of asymmetrical manner with respect to said plane (P) defined by the other two main axes of inertia of said mobile or equipped mobile.

14. Method according to one of the preceding claims, characterized in that factory, prior to said static balancing and dynamic balance, at the level of at least one flange (2), that includes said mobile (1) or mobile equipped (40), radial threaded housings (17) arranged to receive asymmetrical head screws (18) movable in a direction (R) radial to said movable axis (D), and to perform all or part of said adjustment by moving said screwed screws (18) into said threaded housings (17).

15. Method according to one of the preceding claims, characterized in that, when a measurement of unbalance moment resulting from said mobile or mobile equipped with respect to said mobile axis, the imbalance in angular position with respect to a angular mark that includes said mobile (1) or mobile equipped (40).

16. Method according to one of the preceding claims, characterized in that it carries out, prior to said static balancing and dynamic balancing, a flange (2), which comprises said mobile (1) or mobile equipped (40), with a moment of unbalance resulting from a predetermined value.

17. Mobile (1) for scientific instrument or timepiece, comprising at least one shaft (10) arranged to pivot or oscillate about an axis of oscillation aligned on a mobile axis (D) constituted by the axis of said shaft (10), and comprising at least one flange (2) connected to said mobile shaft (10) and protruding radially from said shaft (10), said less flaccid (2) being substantially perpendicular to said mobile axis (D), characterized in that said mobile (1) comprises, of manufacture, a first main axis of longitudinal inertia adjacent said movable axis (D) or merged with him , the two other main axes of inertia together defining a median plane (P), and in that said flange (2) comprises a plurality of housings each receiving a mobile mass adjustable in position in said housing concerned, or only according to a axial direction (A) parallel to said mobile axis (D), or only in a plane perpendicular to a radial (R) from said mobile axis (D).

18. Mobile (1) for scientific instrument or timepiece according to the preceding claim, characterized in that said median plane (P) is located in the thickness of said flange (2).

19. Mobile (1) according to claim 17 or 18, characterized in that each said housing or / and each said corresponding mobile mass comprises stop means for allowing the maintenance of said moving mass in several discrete positions where the center of gravity of said mass is remote from said median plane (P).

20. Mobile (1) according to one of claims 17 to 19, characterized in that each said housing or / and each said movable mass comprises elastic return means for holding in position said movable mass in said housing.

21. Mobile equipped (40) for scientific instrument or timepiece comprising a mobile (1) according to one of claims 17 to 20, characterized in that it further comprises a drive means, or / and a return means or elastic repulsion, or / and a means of return or magnetic repulsion, and / or a means of return or repulsion electrostatic.

22. Mechanism (50) for scientific instrument or timepiece comprising a mobile device (40) according to claim 21 or / and a mobile (1) according to one of claims 17 to 20.

23. Scientific instrument (60) comprising a mechanism (50) according to claim 22 and / or an equipped mobile (40) according to claim 21 or / and a mobile (1) according to one of claims 17 to 20.

24. scientific instrument (60) according to the preceding claim, characterized in that it is a watch, and in that said mobile (1) is a rocker, whose flange (2) is constituted by a disk or a serge, and in that said equipped mobile (40) is a balance spring.