Disengageable winding device, in particular for a timepiece barrel, with a sliding winding gear train - Patents.com

Abstract

To provide a winding device provided with a system for limiting the tightening of a spring, which replaces a system based on the sliding of a strip against notches formed in an internal wall of a drum.SOLUTION: A disengageable winding device 10, in particular for a barrel 2 provided with a spring, comprises: a ratchet 3 mounted on a winding arbor and rigidly connected to the winding arbor; and a winding gear train 40 meshing with the ratchet. Rotation of the arbor winds up the barrel. An actuating wheel set 31 meshes with the winding gear train in an engaged position. The winding gear train is mounted to be able to slide about a rotary arbor 26 out of the engaged position when a torque applied to the winding gear train is substantially greater than a threshold value, in particular when the barrel is fully wound up.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a disengageable winding device, in particular for a timepiece barrel, comprising a sliding winding gear train.

[0002] The invention further relates to a timepiece movement comprising such a disengageable winding device. [Background technology]

[0003] Most of today's self-winding mechanical watches (e.g. wristwatches, pocket watches) have an oscillating weight that drives a gear train, usually by gravity. As the oscillating weight rotates, the arbor is driven by a spring strip, or main spring, wound around an arbor within a drum, which tightens. A pawl prevents reversal and usually limits rotation to only one direction.

[0004] However, when the spring is fully wound, it is important to avoid overwinding, which can cause the spring to break or the resonator to rebound, during which the amplitude of vibration increases until the balance abuts against the horn of the pallet lever, causing the rate to vary as the balance rebounds against this abutment.

[0005] To avoid this risk, such barrels usually have a system that limits the main spring from becoming too tight.

[0006] This restriction is usually accomplished by the outermost strip of the spring sliding against the inside wall of the drum, so that when the spring is fully wound and wrapped around the winding arbor of the barrel, the outermost coil is pressed against the outside wall of the drum.

[0007] Thus, when the winding torque is greater than the friction torque against the wall of the outermost coil, this outermost coil will begin to slip. To prevent unrestrained slippage, the notches allow the ends of the strip to stop slipping once the winding torque is sufficiently reduced.

[0008] However, such a system presents challenges in the sliding friction process of the outermost coil inside the drum. Indeed, when the driving mechanism requires high torque, the bearing forces and friction between the spring strips and the wall become so large that they cause wear and deterioration of the barrel's performance, even if grease is present, which eventually disappears from the friction area after a certain time.

[0009] Also, in an automatic barrel, conflicting demands must be met, such as reducing friction between the coils to maximize efficiency, and increasing friction between the spring and drum to ensure good winding torque.

[0010] Also, deterioration of the drum, such as peeling of the coating, sludge build-up, and wall wear caused by the pressure of the fully wound spring strip, must be avoided. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention aims to overcome all or some of the above problems by providing a winding device with a system to prevent the spring from tightening, replacing systems based on sliding of the strip against notches formed in the inner wall of the drum. [Means for solving the problem]

[0012] To this end, the invention relates to a disengageable winding device, in particular for a barrel with a spring, comprising a ratchet attached to and rigidly connected to a winding arbor and a winding gear train meshing with the ratchet, the winding arbor being, for example, an arbor for winding the barrel, the rotation of which winds the barrel, the rotation of the winding gear train driving the rotation of the ratchet and of the winding arbor, the winding device comprising an actuating wheel set for actuating the winding gear train by applying a torque to the winding gear train, the actuating wheel set meshing with the winding gear train in an engaged position.

[0013] The invention is innovative in that the winding gear train is mounted such that it can slide out of an engaged position around the rotating arbor when the torque applied to the winding gear train is substantially greater than a threshold value, particularly when the barrel is fully wound.

[0014] This allows the winding gear train to move out of engagement so that the ratchet is no longer driven by the winding gear train, in effect, the winding gear train is no longer meshed with the actuating wheel set, for example, when too much torque is applied to the winding gear train by the actuating wheel set, especially when the barrel is fully wound, the winding gear train will slip and will no longer transmit rotational torque to the ratchet, causing the ratchet to not rotate.

[0015] Thanks to the invention, the risk of premature barrel wear is avoided, since the limiting device is located upstream and outside the barrel, and there is no need to use traditional winding limiting devices based on spring friction inside the barrel.

[0016] In certain embodiments of the present invention, the wound gear train and the actuating wheel set are overlapping.

[0017] In certain embodiments of the invention, the actuating wheel set is attached to the rotating arbor such that the actuating wheel set is rigidly connected to the rotating arbor.

[0018] In certain embodiments of the present invention, the actuating wheel set does not mesh with the wound gear train when the wound gear train is sliding.

[0019] In a particular embodiment of the invention, the winding device comprises return means for exerting an axial return force on the winding gear train in the direction of the actuating wheel set to hold the winding gear train in an engaged position.

[0020] In a particular embodiment of the invention, the return means comprises a spring arranged on top of the wound gear train.

[0021] In a particular embodiment of the invention, the winding gear train slides when a torque applied to the winding gear train generates an axial force that is opposite and greater than the force applied by the return means.

[0022] In a particular embodiment of the invention, the actuating wheel set and the wound gear train each have associated wolf teeth.

[0023] The invention further relates to a timepiece movement comprising a barrel and a disengageable winding device for said barrel as described above.

[0024] The objects, advantages and features of the present invention will become clear upon reading some embodiments thereof, given for illustrative purposes only and not intended to limit the scope of the invention, with reference to the attached drawings, in which: [Brief description of the drawings]

[0025] [Figure 1] 1 is a schematic cross-sectional view of a disengageable winding device according to one embodiment of the invention in an engaged position; [Diagram 2]2 is a schematic cross-sectional view of a disengageable winding device according to the embodiment of the present invention shown in FIG. 1 in a disengaged state. [Diagram 3] 2 is a schematic perspective view of a disengageable wrapping device according to the embodiment of the present invention shown in FIG. 1 in an engaged position. [Figure 4] 2 is a schematic perspective view of a disengageable winding device according to the embodiment of the present invention shown in FIG. 1 , disengaged, particularly when the main spring is fully wound; [Diagram 5] 2 is a schematic exploded perspective view of a disengageable wrapping device according to the embodiment of the present invention shown in FIG. 1; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] 1 to 5 show one embodiment of a winding device 10, in this case a barrel 2 for a timepiece, according to the invention.

[0027] The winding device 10 of the barrel 2 comprises a ratchet 3 and a winding gear train 40. The winding gear train 40 meshes with the ratchet 3 such that when the winding gear train 40 rotates in a first direction, the ratchet 3 rotates in a second direction opposite to the first direction.

[0028] The ratchet 3 is attached in a rigid connection to the winding arbor, which makes it possible to wind the barrel 2. The winding arbor is preferably cylindrical.

[0029] In this example, the winding arbor is the winding arbor that winds the barrel 2, and the ratchet 3 is disposed on the barrel 2. The ratchet 3 has a hub 7 attached to the winding arbor so as to provide a rigid connection thereto.

[0030] In an alternative embodiment not shown, the winding arbor is not attached to the barrel and the winding arbor includes a pinion that meshes with a wheel set that drives the winding arbor, which winds the barrel to wind the spring when the ratchet is not attached to the barrel.

[0031] The winding gear train 40 is arranged next to the ratchet 3 and preferably extends in the same plane as the ratchet 3 .

[0032] The ratchet 3 has a first row of external teeth 11 distributed around the ratchet 3. The first row of teeth 11 interlock with a second row of peripheral teeth 22 formed on a first wheel 28 of a winding gear train 40. The winding gear train 40 has a third row of teeth 25 disposed below the first wheel.

[0033] The barrel 2 includes a balance spring (not shown) disposed inside the barrel 2, which must be wound by an automatic or manual winding system.

[0034] For this purpose, the winding device 1 further comprises a gear system 23, which is driven, for example, by the automatic winding weight (not shown) of a timepiece movement. The gear train system 23 can also be driven by means of a winding stem (not shown) which, in the case of manual winding, can be actuated by a winding button.

[0035] The winding actuating wheel set 31 of the gear train system 23 actuates the winding gear train 40. The actuating wheel set 31 includes a second wheel 29 having a fourth peripheral tooth row 27 that interfaces with another wheel set 32 ​​of the gear train system 23. The actuating wheel set 31 includes a fifth tooth row 24 formed on the second wheel 29 that meshes with a third tooth row 25 of the winding gear train 40 in the engaged position.

[0036] Thus, by actuating the gear train system 23, torque is applied to the ratchet 3 which transmits the torque at least partially to the winding arbor via the winding gear train 40 driven by the actuating wheel set 31.

[0037] When the barrel 2 is being wound, rotation of the actuating wheel set 31 and winding gear train 40 rotates the ratchet 3 and thus the winding arbor.

[0038] To avoid overwinding of the barrel 2 , the winding gear train 40 is movable out of the engaged position where it drives the ratchet 3 .

[0039] In this embodiment, the disengageable winding device 10 comprises a rotating arbor 26 on which a winding gear train 40 is slidably mounted about said rotating arbor 26. An actuating wheel set 31 is rigidly attached to the rotating arbor 26.

[0040] The winding gear train 40 meshes with the winding actuating wheel set 31 when in the engaged position and does not mesh with the winding actuating wheel set 31 when sliding along the rotating arbor 26 .

[0041] Thus, in the engaged position, the actuating wheel set 31 drives the winding gear train 40 which in turn drives the ratchet 3 .

[0042] On the other hand, after the sliding of the winding gear train 40 is completed, the actuating wheel set 31 rotates idly and does not drive the winding gear train 40 located at a position away from the actuating wheel set 31. Therefore, the ratchet 3 is no longer driven by the winding gear train 40.

[0043] The winding gear train 40 and the actuating wheel set 31 are stacked one on top of the other. The winding gear train 40 is positioned above the actuating wheel set 31 such that the fifth row of teeth 24 of the actuating wheel set 31 engages with the third row of teeth 25 of the winding gear train 40 in the engaged position.

[0044] The third and fifth rows of teeth 25 preferably have wolf-tooth teeth, i.e., one side of each tooth is less inclined than the other side, which allows the rows of teeth to slide easily against each other in the preferred direction of rotation when they are not sufficiently pressed against each other.

[0045] The winding gear train 40 is capable of sliding axially along the axis of the rotating arbor 26. Thus, the winding gear train 40 is capable of moving axially to and from an engaged position.

[0046] In the engaged position, the winding gear train 40 and the actuating wheel set 31 are in contact via the intermeshing third and fifth tooth rows 25, 24. The actuating wheel set 31 therefore drives the winding gear train 4 and thus the ratchet 3.

[0047] However, in the disengaged configuration, the winding gear train 40 and the actuating wheel set 31 are farther apart and the third tooth row 25 and the fifth tooth row 24 do not mesh with each other. As a result, the actuating wheel set 31 does not drive the winding gear train 4 or the ratchet 3.

[0048] Additionally, the second row of teeth 22 of the winding gear train 40 does not mesh with the first row of teeth 11 of the ratchet 3 when the winding gear train 40 is disengaged. In particular, as the winding gear train 40 has slid along the rotating arbor 26, the second row of teeth 22 has shifted beyond the range of the first row of teeth 11.

[0049] The winding device further comprises return means 50 for exerting an axial return force on the winding gear train 40 in the direction of the actuating wheel set 31 to hold the winding gear train 40 in the engaged position.

[0050] The return means comprises a spring 30 arranged on a wound gear train 40 .

[0051] The wound gear train 40 is attached to a spring 30 which provides an axial force to the wound gear train 40 to hold it in the engaged position.

[0052] The spring 30 is in the form of a flexible collar that is joined to the rotating arbor 26 over the wound gear train 40. The flexible collar is bent or folded over the wound gear train 40 and presses against the wound gear train 40.

[0053] The flexible collar provides an axial return force to the winding gear train 40 in the direction of the actuating wheel set 31 such that the third tooth row 25 and the fifth tooth row 24 interlock in the engaged position.

[0054] Also, when a torque applied to the winding gear train 40 generates an opposing axial force greater than the force applied by the return means 50, the winding gear train 40 slides around the winding arbor 26.

[0055] In particular, due to the wolf tooth-like teeth of the third tooth row 25 and the fifth tooth row 24, a torque applied to the winding gear train 40 generates a force pushing on the winding gear train 40 in the opposite direction to the force generated by the spring 30.

[0056] Thus, when the torque is substantially greater than the threshold value, the wound gear train 40 slides around the rotating arbor 26 out of the engaged position. From the engaged position, the wound gear train 40 slides a certain distance away from the actuating wheel set 31 by performing a substantially linear axial movement around the rotating arbor 26.

[0057] Above the threshold value, when the torque required to rotate the ratchet 3 is greater than the torque required to spread the flexible collar 26 upwards, the winding gear train 40 is pushed by the actuating wheel set 31 by virtue of the third tooth 25 and the fifth tooth 24, in particular by virtue of the wolf tooth-like tooth trains 24, 25.

[0058] That is, when the actuating wheel set 31 pushes hard against the winding gear train 40, the third wolf tooth row 25 and the fifth wolf tooth row 24 slide over each other without interlocking, causing the winding gear train 40 to move as the flexible collar extends upward along the rotating arbor 26.

[0059] As a result, the actuating wheel set 31 continues to rotate, but the winding gear train 40 and ratchet 3 no longer rotate.

[0060] 1 and 3, in the wound configuration, the winding torque provided by the actuating wheel set 31 to the winding gear train 40 is below a threshold value, so the flexible collar does not change shape. Thus, the first tooth row 12 and the ratchet 3 are driven by the winding gear train 40.

[0061] 2 and 4, when the barrel 2 is fully wound, the winding torque applied by the actuating wheel set 31 to the winding gear train 40 is greater than a threshold value, thus causing the flexible collar to expand and the winding gear train 40 to move upwards. That is, the torque required to rotate the ratchet 3 is too great for the flexible collar to retain its initial shape.

[0062] This disengagement means protects the barrel 2 from overwinding and prevents premature wear within the barrel 2. Thus, when the main spring is fully tight, the winding arbor can be blocked without risking breaking the main spring 2.

[0063] The barrel 2 further has a sixth peripheral toothing 18 adapted to cooperate with a seventh toothing of a wheel set of a timepiece movement, for example the third wheel. When wound, the barrel 2 supplies the necessary energy to operate the timepiece movement via the wheel set.

[0064] The invention further relates to a timepiece movement, not shown, comprising a barrel and a barrel winding device as defined above.

[0065] Naturally, the invention is not limited to the embodiments described with reference to the drawings, and alternative embodiments can be considered without departing from the scope of the invention. [Explanation of symbols]

[0066] 2 barrels 3. Ratchet 4-turn gear train 10-wrap device 26 Rotating Arbor 29 Second Car 30 Spring 31 Actuate car set 32 different cars set 40-turn gear train 50 Return means

Claims

1. A disengageable winding device (10) for a barrel (2) equipped with a spring, comprising: The winding device (10) comprises a ratchet (3) attached to a winding arbor for rigid connection thereto, and a winding gear train (40) meshing with the ratchet (3); The winding arbor is an arbor for winding the barrel (2), and the barrel (2) is wound by rotating the arbor; Rotation of the winding gear train (40) drives rotation of the ratchet (3) and rotation of the winding arbor; The winding device (10) comprises an actuating wheel set (31) for driving the winding gear train (40) by applying a torque to the winding gear train (40); The actuating wheel set (31) meshes with the winding gear train (40) in an engaged position; the wound gear train (40) is mounted such that it can slide out of an engaged position about the rotating arbor (26) when a torque applied to the wound gear train (40) is substantially greater than a threshold value; The actuating wheel set (31) does not mesh with the winding gear train (40) when the winding gear train (40) is sliding.

13. A winding device comprising:

2. The winding gear train (40) and the actuating wheel set (31) overlap in the engaged position.

2. The winding device of claim 1.

3. The actuating wheel set (31) is attached to the rotating arbor (26) so as to be rigidly connected to the rotating arbor (26).

2. The winding device of claim 1.

4. A return means (50) for applying an axial return force to the winding gear train (40) in the direction of the actuating wheel set (31) to hold the winding gear train (40) in an engaged position.

2. The winding device of claim 1.

5. The return means comprises a spring (30) arranged on the winding gear train (40).

5. The winding device according to claim 4.

6. The winding gear train (40) slides when a torque applied to the winding gear train (40) generates an axial force that is opposite to and greater than the force applied by the return means (50).

5. The winding device according to claim 4.

7. The actuating wheel set (31) and the winding gear train (40) each have wolf teeth (24, 25) that are interlocked with each other.

2. The winding device of claim 1.

8. The winding gear train (40) and the actuating wheel set (31) each have a second radial tooth row (22, 27).

8. The winding device according to claim 7.

9. A method for winding a barrel (2) comprising the steps of: (a) winding the barrel (2) using a winding device (10) according to any one of claims 1 to 8; A timekeeping movement characterized by:

Images