Watch Movements

Abstract

1. A timepiece movement comprising: a main frame serving as a support for a power source and at least one base gear train arranged to be driven by said power source; and at least one levitating bridge mounted in cantilever fashion on a member of said main frame and extending over said main frame, said levitating bridge carrying at least one functional member dynamically connected to said base gear train via a levitating gear train, said functional member and at least some members of said levitating gear train being entirely supported by said levitating bridge.

Description

TECHNICAL FIELD TO WHICH THEINVENTION BELONGS

[0001] The present invention relates to the field of watchmaking, and more particularly to a watch movement having a particular frame structure. [Background technology]

[0002] In so-called "complex" watches, i.e. watches that include several additional mechanisms, one of the problems often encountered is the lack of volume in the movement to place the various mechanisms and / or to place the display elements, animations, and other visual elements on the dial. When a movement is crowded, the most commonly used solution is to place the mechanisms at (a set of) additional heights, by increasing the thickness of the movement. This results in a very thick movement and therefore a large watch case. The MB&F "Legacy Machine" series solves this problem to some extent. In this construction, the balance and balance spring assembly is mounted between a first bearing conventionally placed on the frame and a second bearing carried by a pair of cantilever arms that carry the mechanism and constitute a levitating bridge. However, the escapement system is still placed on the frame in a relatively conventional way, requiring a passage for the balance shaft. The conventional placement of one of the bearings for the balance shaft on the frame implies the constraints of the conventional construction regarding the pivoting on the frame as well as the placement of the escapement.

[0003] When placing visual elements, animations, etc., a common solution is to place some of these visual elements on the back of the watch so that they are visible through a transparent caseback, but these elements are not visible when the user is wearing the watch, and it is necessary to remove the watch and turn it over to be able to see these displays. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE DISCLOSURE The object of the present invention is therefore to propose a timepiece movement in which one or other of the aforementioned drawbacks is at least partially overcome. [Means for solving the problem]

[0005] More specifically, the invention relates to a timepiece movement as defined by claim 1, said movement comprising: - a main frame, typically including a plate and at least one bridge, which serves as a support for a power source and at least one base gear train arranged to be driven by said power source; - at least one levitation bridge cantilevered onto a member of said main frame and extending over said main frame; Equipped with.

[0006] According to the invention, the levitation bridge carries at least one functional member, such as a display member, a regulating system (such as a balance-hairspring-escapement system), a rotor seat, etc., dynamically connected to the base gear train via a levitation gear train. Moreover, the functional member and at least some members of the levitation gear train are entirely supported by the levitation bridge. In other words, the members are pivoted only by the levitation bridge, without using any bearings arranged on the main frame.

[0007] By these means, the functional elements, whether the display elements, the regulating device (or elements thereof) or other elements, can be arranged superimposed on the main frame, without the need for supported bearings. This creates space in the movement without many steps on the main frame, not only on the main frame but also on the levitating bridge, thus giving the manufacturer more freedom. In fact, when the movement is packed, the levitating bridge extends in the gap between the main frame and the glass (or alternatively the caseback - which can also be transparent), thus using space that would not normally be used.

[0008] Advantageously, the entire levitation gear train is fully supported by the levitation bridge.

[0009] In one particular embodiment, the movement can include at least two levitation bridges, each carrying a respective levitation gear train. These levitation gear trains can be independent of each other or can engage with each other at a respective gear of each levitation gear train in order to transmit torque from one side of the main frame to the other. In particular, this engagement can be performed at the level of the last gear of each levitation gear train.

[0010] The invention also relates to a timepiece comprising a case closed on at least one side by a glass, and a movement as described herein and mounted on said case, in which said functional members and said levitating bridge are arranged between said main frame and said glass. [Brief description of the drawings]

[0011] Other details of the invention will become clearer on reading the following description, made with reference to the accompanying drawings, in which: [Figure 1] 1 is a schematic cross-sectional view showing a part of a timepiece movement according to the present invention; [Diagram 2]FIG. 2 is an isometric view of a portion of another variant of a clock movement according to the invention, including two levitation bridges carrying intermeshing levitation gear trains. [Diagram 3] 1 is a schematic diagram of a part of another variant of a timepiece movement according to the invention, in which a levitating bridge carries the regulating system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 1 shows diagrammatically part of a timepiece movement 1 according to the invention, which comprises a main frame 3 including a plate and at least one bridge, as is generally known and therefore does not need to be described in detail.

[0013] The main frame 3 carries a power source 5, here shown as a conventional barrel, which houses a mainspring. Other types of power source 5, such as an electric motor, may also be used in the movement 1 according to the invention. The power source 5 may be pivotally mounted between the two frame members, or it may be mounted in a levitating manner, supported on only one of its sides, as is commonly known.

[0014] A power source 5 drives a partially illustrated main gear train 7 (the remainder of which is shown diagrammatically by the bold arrow), which is supported by a frame and includes a number of gears, one or more belts, chains, or the like, or a combination of such members, as is commonly known. Furthermore, the type of gear tooth profile may be straight cut, as well as helical, inclined, crowned, or the like, depending on the needs of the construction and the geometry of the bridge.

[0015] In this case, the gear train 7 also drives a regulating system 9 attached to the main frame 3, for example any kind of balance-hairspring-escapement type, one-axis, two-axis or three-axis tourbillon, carousel or any other known regulating system used to determine the speed of the movement. Furthermore, each of the regulating systems may or may not be inclined with respect to the plane of the main frame 3.

[0016] The timepiece movement also includes a floating bridge 11 mounted in a cantilever manner on the mainframe 3, in particular on a bridge or on a plate of the mainframe 3. In other words, the floating bridge has one end fixed to the mainframe 3 and one end free. The floating bridge 11 extends over the mainframe 3 and carries at least one functional member 13, in this case hands arranged to display timepiece information such as seconds, minutes, hours, day of the week, date, week number, moon phase, etc. Instead of hands, it is also possible to provide disks or other types of display members. Likewise, the display mechanism may be, for example, retrograde, jump, or any type of mechanism known to the person skilled in the art.

[0017] This functional member 13 is entirely supported by the levitating bridge 11, by a pair of bearings 15a, 15b arranged on either side of the levitating bridge 11, or by any other special arrangement serving to support it. It is clear that any type of bearing may be envisaged, for example a ball bearing or any other type of bearing known to the person skilled in the art.

[0018] The functional member 13 is rotatably fixed to member 17a of a levitation gear set 17 consisting of three gears 17a, 17b, 17c, each of which is entirely supported by the levitation bridge 11. The gears form a gear train which is driven by a drive wheel 7a attached to the main frame 3 and by the power source 5. In the illustrated embodiment, the gears 17a, 17c each comprise a single toothed gear and the gear 17b comprises a gear and pinion, although other combinations of toothed members are possible. By "fully supported" we mean that the gears 17a, 17b, 17c pivot exclusively on the levitation bridge without the use of any bearings located on the main frame 3.

[0019] As shown, all of the gears 17a, 17b, 17c are mounted on the underside of the levitating bridge 11 facing the main frame 3, although it is possible for all to be mounted on the opposite side of the bridge 11 facing the user. Additionally, a combination of toothed members on both sides of the levitating bridge 11 is also possible, in which case at least some of the gears include toothed members on both sides of the bridge, which may be connected to each other by shafts, tubes, etc.

[0020] It is also possible to provide several function members 13, each fixed for rotation with a different gear 17a, 17b, 17c of the levitation gear train 17. By appropriately adapting the gear ratios, the levitation gear train can function as a dial train, for example displaying the hours by a function member 13 fixed for rotation with gear 17a and the minutes by a function member fixed for rotation with or driven by gears 17b or 17c. In this way, depending on the inclination of the gears 17a, 17b, 17c of the levitation gear train, it is possible to have additional function members fixed to some (or indeed all) of the latter, each with a different inclination, parallel to the axis of the respective gear. This can give the watch a unique appearance.

[0021] As shown in FIG. 2, where the parts carried by the main frame 3 are not shown, it is also possible to provide several levitation bridges 11 and levitation gear trains 17, which can engage with each other at their last gear 17a. Alternatively, it is also possible that two levitation gear trains 17 do not directly cooperate with each other. Such an arrangement allows the watchmaker to provide, for example, a space in the middle of the movement 1, the majority of whose parts form part of the levitation gear train 17. This space may be transparent and may contain any object (sculpture, animation, game device, etc.).

[0022] In the variant shown, each gear 17a carries a functional member 13 such as a pointer, but it is also possible to provide only one functional member carried by one or the other of the levitation gear trains 17. In this configuration, the pointers rotate in opposite directions with an angular velocity ratio that depends on the gear ratio between the two gears 17a. It is also possible to interpose an intermediate gear between the two wheels 17a, or to mount one of the pointers, rotationally fixed by gear 17b, on one or the other of the levitation gear trains 17. Alternatively, two levitation gear trains 17 can be used to transmit torque from one to the other of the main frames, without the need for bulky gear trains or crown wheels passing through the main frames.

[0023] Figure 3, in which the parts carried by the main frame 3 are also not shown, shows yet another embodiment in which the regulating system 9 is carried by the levitating bridge 11 instead of being placed on the main frame 3. In the illustrated variant, the regulating system 9 comprises a balance 21-hairspring 23 assembly kept in oscillation by a conventional escapement system 25. The regulating system 9 is considered a functional part within the meaning of the present invention. Alternatively, other types of regulating systems (detent escapement, tourbillon, carousel, etc.) may be used.

[0024] The balance 21 may be mounted so as to be supported on only one of its faces (the "floating balance"), for example by being supported on the floating bridge 11 via a ball bearing, or the floating bridge 11 may comprise a plate (not shown) carrying a conventional bearing, which plate is fixed to the floating bridge 11 by means of screws or the like, for example cooperating with an opening 11a.

[0025] In the construction shown, wheel 17d is an escapement gear including a pinion 17d1 located on the underside of floating bridge 11 and an escapement gear 17d2 located on the above side of floating bridge 11. The escapement gear cooperates with anchor 25a in a known manner and clearly illustrates the principle that a wheel can include toothed members located on either side of bridge 11.

[0026] By these means, the balance 21-hairspring 23-escapement 25 assembly, located on the levitation bridge, regulates the speed of the base gear train 7 driven by the power source 5. These last two components are not shown in FIG. 3.

[0027] Other alternatives based on the principles described above are also possible: for example, the functional member carried by the levitating bridge 11 could be any type of animation, a device displaying any kind of horological information related to time or movement (such as power reserve), an oscillating weight arranged to wind the barrel 5, or the like.

[0028] From the above, it is clear that when the movement 1 is housed, the floating bridge 11 as well as the functional members 13, 21 are interposed between the main frame 3 and the glass, whether on the central side or on the rear side.

[0029] It should also be noted that other standard components such as the dial, the watch case, winding and / or time setting means, etc. are not represented.

[0030] Although the invention has been described above with reference to specific embodiments, other and additional modifications are also possible without departing from the scope of the invention as defined by the claims.

Claims

1. a main frame serving as a support for a power source and at least one base gear train arranged to be driven by said power source; - at least one levitating bridge mounted in a cantilever manner on a member of said main frame and extending over said main frame, the levitating bridge carries at least one functional member dynamically connected to the base gear train via a levitating gear train, the functional member and at least some of the members of the levitating gear train being entirely supported by the levitating bridge; the levitation bridge has a surface facing the main frame; The levitation gear train includes a plurality of gears; the at least one functional member and the plurality of gears of the levitation gear train are fully supported by the levitation bridge, the plurality of gears being mounted on the face of the levitation bridge facing the main frame; A movement characterized by:

2. 2. The movement according to claim 1, wherein the functional member is a display member.

3. 2. The movement according to claim 1, wherein the functional member is a regulating system.

4. 2. The movement according to claim 1, wherein the member is a pendulum seat.

5. A movement according to any one of the preceding claims, comprising at least two levitation bridges, each carrying a respective levitation gear train.

6. 6. The movement of claim 5, wherein the levitation gear trains are intermeshing.

7. 7. A movement according to claim 6, wherein the levitation gear trains engage with each other at the height of the last gear of each of the levitation gear trains.

8. A timepiece comprising a case closed on at least one side by a crystal and a movement according to any one of claims 1 to 7 and placed in said case, the functional member and the at least one levitation bridge are disposed between the main frame and the glass; clock.

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