Device for retaining movable part

Abstract

To provide a device for axially retaining two coaxial elements of which at least one rotates by inserting a clip in a radial direction.SOLUTION: A device is for retaining a moving part 2 of a timepiece movement 100 axially around a shaft 3, and the moving part 2 includes a barrel part 4 arranged so as to be coaxially mounted to the shaft 3. The device includes a clip 1 intended to be mounted to the barrel part 4 of the moving part 2, and the clip 1 includes resilient retaining means so as to cooperate with the barrel part 4, and grip the barrel part 4 over a part of an outer circumference of the barrel part. The clip 1 includes a lock beak that passes through an opening extending radially inward with respect to the barrel part 4, and the lock beak is arranged to retain the moving part 2 in a prescribed position axially in cooperation with a slot of the shaft 3.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of timepieces, and more particularly to the field of wristwatches. More specifically, the present invention relates to a device for holding and rotatably guiding the moving parts of a watch movement.

Background Art

[0002] The prior art includes numerous documents relating to devices for holding moving parts.

[0003] Methods of fastening the moving parts of a movement with screws, driving them into arbors, and using retaining rings are disclosed. For example, multiple moon-phase display disks are typically held by screws or arbors at their centers, or by guide rings, which can increase the thickness of the movement.

[0004] Another traditional method of guiding watch moving parts is to pivot the watch moving parts between two bearings, each supported by a blank (plate, cock, retaining plate, etc.).

[0005] For functional reasons, especially due to wear or lubrication, bearings are typically components assembled to the blanks, thus requiring an assembly operation. Bearings can be made of metal or minerals, and are known to be made of brass or bronze, or of ceramics or rubies, etc.

[0006] This architecture therefore requires the manufacture and assembly of various components, which is costly both economically and in terms of the space occupied by the movement.

[0007] An inexpensive way to overcome this problem is simply to remove one of these blanks. When the moving part of the problem is the hour wheel, it is inserted into the cannon pinion, which functions as a radial guide and an axial stop element only in one direction (towards the gear train side).

[0008] The hour wheel is not held in the other direction (towards the dial side) until the dial is installed. In such a case, it is not possible to provide a movement without a dial, such as a so-called "skeleton" movement. This is because without an axial stopper on the dial side, the moving part cannot be maintained in a predetermined position. Also, obviously, inserting such a movement into a watch case cannot be easily done with this type of moving part.

[0009] There are various solutions, but all have the following drawbacks. · The moving part needs to be delivered as a spare part. As a result, very delicate lubrication has to be done by the case installer (who has no experience in this field) rather than the movement assembler. · The movement needs to be delivered in a protective container, and its cover functions as a stopper. When the moving part of the problem is the hour wheel, this moving part can protrude to fit different dial thicknesses attached to this movement by existing in various lengths. This solution solves the lubrication problem, but it is necessary to use a protective container cover adapted to the length of each moving part, making the logistics very complicated. · The movement needs to be delivered with a retaining clip. This clip needs to be inserted when assembling the movement. This solution solves the problems of lubrication and the logistics regarding the protective container. However, this component needs to be manufactured and assembled only to enable the delivery of the movement to the case fitter. Considering the small size of the component, it is difficult to clean and readjust, and difficult to reuse. Finally, when removing the movement, there is a high risk of damaging the movement due to excessive force, for example, being pulled out from the wrong direction, or being scratched by the extraction pliers.

[0010] Note that none of the proposed solutions solve the problem of the movement without a dial. This is because with the solutions described, although the movement can be delivered to the case fitter, once the case is attached, the movement cannot be kept in a functional state.

[0011] Since the prior art does not provide a solution that is easy to implement at an affordable price, there is a need to provide an alternative to the existing solutions.

Summary of the Invention

[0012] The object of the present invention is to overcome the drawbacks of the prior art by proposing a device for axially retaining two coaxial elements, at least one of which rotates, by radially inserting a clip. This clip generates no or almost no frictional torque with the first element, even though the first element is integral with the second element.

[0013] That is, the present invention relates to a device for axially retaining the moving part of a watch movement around a shaft, the moving part including a cylindrical part configured to be coaxially attached to the shaft, and the device including a clip intended to be attached to the cylindrical part of the moving part.

[0014] According to the present invention, the clip includes elastic holding means configured to cooperate with a groove formed in the cylindrical portion and be held in the groove, and further includes a locking jaw that passes through an opening extending radially inward with respect to the cylindrical portion, and the locking jaw cooperates with a slot in the shaft to hold the movable part in a predetermined axial position.

[0015] According to another advantageous alternative embodiment of the present invention, · The cylindrical portion includes a groove formed in all or part of its outer circumference, · The clip has a ring body having two arms with open ends, at least one of the two arms being elastically deformable, and these arms forming the holding means, · The clip has an inner radius smaller than the radius of the cylindrical portion or the groove, so that elastic deformation of the elastic holding means is obtained and it is guaranteed that they are held in the cylindrical portion without play, · The clip includes handling means, · The jaw is arranged at one of the open ends, · The ring body has two arcs for each arm, · The locking jaw is longer than the depth of the opening, · The clip is made of wire, · The clip has an elliptical shape such that only the ends of the arms are placed in the groove facing the outer circumference of the cylindrical portion and the locking jaw is placed in the opening, · The device includes a metal foil arranged on the movable part, and the clip holds both the movable part and the metal foil.

[0016] According to another aspect, the present invention relates to a movement including the device according to the present invention.

Brief Description of the Drawings

[0017] Other features and advantages of the present invention will become apparent from the following detailed description, given by way of example with reference to the accompanying drawings and in no way limiting.

[0018]

Figure 1

Figure 2

Figure 3

Figure 4a

Figure 4b

Figure 4c

Figure 4d

Mode for Carrying Out the Invention

[0019] Here, a device for holding an hour wheel on a barrel according to the present invention will be exemplarily described with reference to FIGS. 1 to 3. For those skilled in the art, it is not difficult to adapt this device to any other type of movable part, whether it pivots around a rotating shaft or not.

[0020] According to the illustrated embodiment, the clock movement is intended for the design of a clock including a movable part that constitutes an hour display, and therefore includes a device for driving this movable part. Since the structure of such a driving device is well-known, it will not be further described here.

[0021] Needless to say, the present invention is also applicable to any type of movable part that pivots around a shaft, such as a movable part for displaying the moon age, minutes, date, a lever, or an intermediate wheel.

[0022] The present invention relates to a device for holding a movable part 2 such as a wheel of a clock movement 100 attached to a shaft 3. The device includes a clip 1. The clip 1 is intended to be attached to the barrel 4 of the movable part 2 and to cooperate with the shaft 3 between a first position and a second position.

[0023] Advantageously, the clip 1 includes elastic retaining means 10, 11 in the form of two arms intended to cooperate with the barrel 4 or with a groove 40 made in this barrel, and a locking beak 12 intended to cooperate continuously with the opening 41 of the barrel 4 and the slot 30 of the shaft 3 so as to axially hold the movable part 2 on the shaft in a first position and to axially free this movable part 2 in a second position. The clip 1 is intended to be able to move translationally between a first position called the locked position and a second position called the unlocked or free position where the clip 1 can be removed.

[0024] As shown in FIG. 1, the clip 1 is in the form of a ring body having two arms 10, 11 with open ends (or free ends). Each arm is elastically deformable so as to be gripped in the groove 40 when the clip 1 is attached to the barrel 4, and the groove 40 extends continuously (or partially) around the circumferential direction of the barrel 4.

[0025] As shown in the figure, the clip 1 further has a locking beak 12 in the same plane as the plane formed by the two arms 10, 11.

[0026] The clip 1 includes a locking beak 12 passing through the opening 41 made in the barrel 4. The end thereof fits into the slot 30 of the shaft 3 to axially hold the movable part 2 on the shaft 3. In this way, the clip 1 prevents the movable part 2 from sliding along the shaft 3.

[0027] The locking beak 12 has a length greater than the depth of the opening 41 and slightly smaller than the distance between the bottom of the slot 30 and the base of the beak 12. Thereby, friction between the beak 12 and the shaft 3 is prevented and the movable part 2 is securely held on the shaft 3.

[0028] By the cooperation of the elastic retaining means 10, 11 and the groove 40, it is possible to both guide and securely hold the clip 1 on the movable part 2. That is, once the clip 1 is in a predetermined position, axial movement of the clip 1 along the shaft 3 of the movable part 2 is prevented, so that the movable part 2 does not come off the shaft 3. Such an arrangement is particularly effective when the movement is delivered before being mounted in the case. This is because the movable part can be attached and held in a predetermined position while the movement is being delivered.

[0029] Advantageously, since the clip 1 only grips the barrel 4, the gripping torque is not transmitted to the shaft 3.

[0030] According to the embodiment shown in FIG. 2, the clip 1 has an inner radius smaller than the radius of the barrel 4 or the radius of the groove 40. Therefore, the arms 10, 11 of the clip 1 are elastically deformed and held without play at a predetermined position on the barrel 4.

[0031] Note that the clip 1 can also be used to axially hold elements other than the movable part 2, such as a metal foil 5 disposed on the movable part 2. That is, the clip 1 can be used to axially hold a plurality of elements simultaneously.

[0032] The clip 1 may be made of a material selected from an elastically deformable plastic material or metal.

[0033] According to an alternative embodiment shown in FIG. 4a, the ring body of the clip 1 has two arcs for each of the arms 10, 11. Such a configuration makes it possible to form a stopper notch and two positions that can be easily distinguished by the operator while preventing the loss of the clip.

[0034] Clip 1 may further include handling means such as tab 15 with an opening 16 provided optionally to facilitate handling of clip 1, as shown in FIG. 4b. Arms 10, 11 may optionally have an elliptical shape so that, as shown in FIG. 4c, only the ends of arms 10, 11 are placed in groove 40 so as to face the outer periphery of shaft 2, and serve as handling means with an opening 17 provided optionally to facilitate handling of clip 1.

[0035] According to yet another alternative embodiment shown in FIG. 4d, clip 1 is also in the form of a ring body with two arms 10, 11 having open ends, and one of the ends 10 or 11 is bent inwardly with respect to clip 1 so as to form a locking jaw 12 arranged to cooperate with opening 41 of barrel 4.

[0036] As shown in FIG. 4d, clip 1 is positioned on shaft 3 as follows. First, the bent end forming the locking jaw is placed in opening 41 of barrel 4. Next, the other open end is passed around the barrel so that the free arm extends along groove 40 and engages with groove 40 until the clip occupies the locked position.

[0037] In another alternative embodiment shown in the drawings, clip 1 is positioned on shaft 3 as follows. First, clip 1 is positioned on barrel 4 with the locking jaw facing opening 41, and the arms are pre-engaged with groove 40 so that clip 1 is guided across barrel 4. The operator then presses clip 1 against barrel 4 and passes opening 41 until locking jaw 12 enters slot 30 of shaft 3 and the clip occupies the locked position.

[0038] Clip 1 is removed in a direction opposite to its insertion. In the particular case of the alternative embodiment shown in FIG. 4c, the inner radius of the arm is not coaxial with the radius of barrel 4 or the radius of groove 40. This allows a radial stress directed towards the center of the barrel to act so as to spread away from the open ends of arms 10, 11 and facilitate removal of the clip. In such a case, opening 17 can be used to hold the end of the tool against clip 1, so there is no risk of the tool slipping and damaging the movement.

[0039] Thanks to these various aspects, the present invention provides a device for holding a moving part of a timepiece movement that is easy to attach / detach and reliably holds the moving part on its shaft during transport of the timepiece movement.

[0040] The above description corresponds to a preferred embodiment and should not be considered limiting in any situation. In particular, it should not be considered limiting with respect to the forms described for the different structural elements or their materials constituting the assembly device.

Claims

1. A device for axially holding a movable part (2) of a timepiece movement (100) around a shaft (3), said movable part (2) including a cylindrical part (4) arranged to be coaxially attached to said shaft (3), said device including a clip (1) intended to be attached to said cylindrical part (4) of said movable part (2), characterized in that said clip (1) includes elastic retaining means (10, 11) arranged to cooperate with said cylindrical part (4) and to grip said cylindrical part over a part of its outer periphery, said clip (1) including a locking jaw (12) passing through an opening (41) extending radially inwards with respect to said cylindrical part, said locking jaw (12) being arranged to cooperate with a slot (30) of said shaft (3) to axially hold said movable part (2) in a predetermined position, a device.

2. The device according to claim 1, characterized in that said cylindrical part (4) includes a groove (40) formed in all or part of its outer periphery.

3. The device according to claim 1, characterized in that said clip (1) has a ring body having two arms (10, 11) with open ends, at least one of said two arms being elastically deformable, said arms (10, 11) forming said retaining means.

4. The device according to claim 1, characterized in that said clip has an inner radius smaller than the radius of said cylindrical part (4) or said groove (40) in order to obtain elastic deformation of said elastic retaining means (10, 11) and to ensure that they are held without play in said cylindrical part (4).

5. The device (1) according to claim 1, characterized in that said clip (1) includes handling means (15, 16, 17).

6. The device according to claim 1, characterized in that said jaw (12) is arranged at one of said open ends.

7. The device according to claim 1, characterized in that said ring body has two arcs per arm.

8. The device according to claim 1, characterized in that said clip (1) is made of wire.

9. The device according to claim 1, characterized in that the clip (1) has an elliptical shape such that only the ends of the arms (10, 11) are placed in the groove (40) so as to face the outer periphery of the shaft (2), and the locking jaw (12) is placed in the opening (41).

10. The device according to claim 1, comprising a metal foil (5) arranged on the movable part (2), characterized in that the clip (1) holds both the movable part (2) and the metal foil (5).

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