Horological regulating member having a balance spring and provided with temperature- compensation means

Abstract

A regulating member (1) for a horological movement including an oscillating weight, for example a balance, and a balance spring including a flexible strip (2) wound about itself in a plurality of turns, the strip (2) having a predefined rigidity to allow the oscillating weight to undergo a rotary oscillatory motion, the strip (2) including an outer end (9), wherein the regulating member (1, 10) includes a temperature-compensating resilient device configured to adapt the stiffness thereof as a function of the temperature to compensate for the effect of temperature on the regulating member (1, 10), the resilient device including a resilient element (5) connecting the outer end (9) to a first support (7) that is stationary relative to the horological movement, as well as preloading means (6) for applying a variable force or torque to the resilient element (5) as a function of the temperature.

Claims

1. A regulating member for a horological movement comprising an oscillating weight and a balance spring comprising a flexible strip wound about itself in a plurality of turns, the strip having a predefined rigidity to allow the oscillating weight to undergo a rotary oscillatory motion, the strip comprising an outer end, wherein the regulating member comprises a temperature-compensating resilient device configured to adapt the stiffness thereof as a function of the temperature to compensate for the effect of temperature on the regulating member, the resilient device comprising: a resilient element connecting the outer end to a first support that is stationary relative to the horological movement, and preloading means for applying a variable force or torque to the resilient element as a function of the temperature, wherein the resilient element is connecting the outer end to the preloading means.

2. The regulating member according to claim 1, wherein the preloading means comprise a spring part connected to the resilient element, the spring part transmitting the force or torque to the resilient element.

3. The regulating member according to claim 1, wherein the preloading means comprise a body that can deform as a function of temperature, the deformable body being at least partially in contact with the spring part during the deformation.

4. The regulating member according to claim 3, wherein the deformable body is an elongate bimetallic attachment.

5. The regulating member according to claim 4, wherein the spring part comprises a first flexible blade connected to the resilient element.

6. The regulating member according to claim 5, wherein the spring part comprises a translation stage connected to the first flexible blade, the deformable body being in contact with the translation stage.

7. The regulating member according to claim 5, wherein the spring part comprises a second flexible blade connected to the thermally deformable body.

8. The regulating member according to claim 1, wherein the regulating member extends substantially in one and the same plane.

9. A regulating member for a horological movement comprising an oscillating weight and a balance spring comprising a flexible strip wound about itself in a plurality of turns, the strip having a predefined rigidity to allow the oscillating weight to undergo a rotary oscillatory motion, the strip comprising an outer end, wherein the regulating member comprises a temperature-compensating resilient device configured to adapt the stiffness thereof as a function of temperature to compensate for the effect of temperature on the regulating member, the resilient device comprising a resilient element connecting the outer end to a first support that is stationary relative to the horological movement, as well as preloading means for applying a variable force or torque to the resilient element as a function of the temperature, and wherein the resilient element comprises a suspended point-shaped body and a pair of non-crossing blades connecting the suspended point-shaped body to the first stationary support.

10. The regulating member according to claim 9, wherein the preloading means are connected to the suspended point-shaped body so as to exert the force or torque on the suspended point-shaped body.

11. A regulating member for a horological movement comprising an oscillating weight and a balance spring comprising a flexible strip wound about itself in a plurality of turns, the strip having a predefined rigidity to allow the oscillating weight to undergo a rotary oscillatory motion, the strip comprising an outer end, wherein the regulating member comprises a temperature-compensating resilient device configured to adapt the stiffness thereof as a function of temperature to compensate for the effect of temperature on the regulating member, the resilient device comprising a resilient element connecting the outer end to a first support that is stationary relative to the horological movement, as well as preloading means for applying a variable force or torque to the resilient element as a function of the temperature, and wherein the regulating member further comprises means for regulating the preloading means so as to apply a variable force to the preloading means.

12. A horological movement comprising a regulating member according to claim 1.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The purposes, advantages and features of the present invention will become apparent after reading several embodiments, which are provided for purposes of illustration only and not intended to limit the scope of the invention, given with reference to the accompanying drawings, wherein:

(2) FIG. 1 is a diagrammatic top view of a regulating member according to a first embodiment of the invention, and

(3) FIG. 2 is a diagrammatic top view of a regulating member according to a second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(4) FIGS. 1 and 2 show two embodiments of a regulating member according to the invention.

(5) In both embodiments, the regulating member 1, 10 comprises a balance spring provided with a flexible strip 2 wound about itself in a plurality of turns. The flexible strip 2 comprises an outer end 9 and an inner end 8.

(6) The regulating member 1, 10 comprises an oscillating weight, for example an annular balance, not shown in the figures, which is connected to the inner end 8 of the strip 2, the strip 2 having a predefined rigidity to enable the oscillating weight to undergo a rotary oscillatory motion. For example, the oscillating weight comprises an axial rotating shaft, the inner end 8 of the strip 2 being connected to said shaft.

(7) Preferably, the regulating member 1, 10 extends substantially in the same plane, except for the oscillating weight, which oscillates in a parallel plane above the balance spring.

(8) According to the invention, the regulating member 1, 10 comprises a resilient device 50 for compensating for an external parameter, which device is configured to adapt the stiffness of the resilient element 5 as a function of the temperature so as to compensate for the effect of temperature on the regulating member 1, 10.

(9) The resilient device 50 comprises a resilient element 5 connecting the outer end 9 to a support 7 that is stationary relative to the horological movement, for example to a plate. The resilient device 50 further comprises preloading means 6 for applying a variable force or torque to the resilient element 5 as a function of the external parameter.

(10) The resilient element 5 comprises, in this case, a suspended point-shaped body 3 and a pair of non-crossing blades 4 connecting the suspended point-shaped body 3 to the stationary support 7. The suspended point-shaped body 3 is, for example, a cylindrical body with a height substantially equal to the diameter, with the non-crossing blades 4 extending from the suspended point-shaped body 3 as far as the stationary support 7.

(11) The resilient element 5 is arranged in the continuation of the flexible strip 2, the balance spring and the resilient element 5 being adjacent, but while avoiding contact during the oscillation of the oscillating weight.

(12) The preloading means 6 are configured to exert the force or torque on the suspended point-shaped body 3. The preloading means 6 comprise a spring part provided with a flexible blade 11 connected to the suspended point-shaped body 3. The first flexible blade 11 extends along the axis of the resilient element, tangentially to the balance spring, and is slightly offset from the outer end 9.

(13) In the first embodiment shown in FIG. 1, the spring part of the preloading means 6 comprises a translation stage provided with a first L-shaped movable element 12 and a second support 13 that is stationary relative to the movement. The first movable element 12 is connected to the flexible blade 11 by one end of a first arm of the L shape. The second arm of the L shape includes a rounded protrusion 53 on the outer side. The translation stage comprises two substantially parallel flexible blades 14 connecting the first movable element 12 to the second stationary support 13.

(14) The preloading means 6 further include a thermally deformable body 15 that deforms as a function of temperature, the deformable body 15 exerting the variable force or torque on the movable element 12.

(15) In this example, the thermally deformable body 15 is a bimetallic attachment whose deformation is caused by temperature. The bimetallic attachment has a body that extends longitudinally, and comprises two elongate parts 51, 52 joined longitudinally with one another. The two elongate parts 51, 52 are each made of a different material, with different thermal deformation properties from one another. Thus, under the effect of heat, the bimetallic attachment deforms laterally, one end 55 of the bimetallic attachment being retained, the other end being able to move and deform the bimetallic attachment so as to bend it on one side.

(16) The bimetallic attachment is disposed perpendicular to the movable element 12, such that a first free part 54 is in contact with the protrusion 53 of the second arm of the L shape. The retained end 55 is held by a second translation stage comprising a second movable element 18 and a second pair 17 of parallel flexible blades connecting the second movable element 18 to a third support 19 that is stationary relative to the plate of the movement. The second movable element 18 is L-shaped, with one arm of the L shape supporting the retained end 55 of the bimetallic attachment, whereas the blades of the second pair 17 of blades connect the inner face 56 of the second arm to the third stationary support 19. The blades of the second pair 17 of blades are arranged perpendicular to the bimetallic attachment when the preloading means 6 are in the rest position.

(17) In the event of a change in temperature, the deformable body 15, in this case the bimetallic attachment, bends or straightens, such that the first free part 54 exerts a greater or lesser force on the protrusion, and thus on the first movable element 12, which moves while being guided by the first translation stage. Thus, via the first flexible blade 11, the resilient element 5 receives a force or a torque modifying the stiffness thereof and thus the rate of the regulating member 1.

(18) Regulating means, such as a screw, can be added to exert a force 57 on the second movable element 18, in particular at the end of the second arm 58, parallel to the longitudinal axis of the bimetallic attachment. The effective length d of the bimetallic attachment can thus be regulated in order to regulate the effect of the preloading means 6 on the resilient element 5, in particular as a function of temperature. By displacing the second movable element 18, which is guided by the second translation stage, the contact between the free part 54 and the protrusion 53 is modified, thus increasing or decreasing the effective length d of the bimetallic attachment. Therefore, the greater the effective length, the more the force exerted on the first moving element 12 varies as a function of temperature.

(19) In the event of curved deformation of the deformable body 15, the free part 54 pushes the first movable element 12, such that the first flexible blade 11 transmits a force or torque to the suspended point-shaped body 3. The stiffness of the pair of non-crossing blades 4 is thus decreased. Conversely, if the deformable body 15 straightens, the force or a torque on the suspended point-shaped body 3 decreases, such that the stiffness of the pair of non-crossing blades 4 is increased.

(20) In the second embodiment, the regulating member 10 comprises a balance spring, an oscillating weight (not shown in the figure), a resilient element 5, and a first flexible blade 11 that is identical to the first embodiment.

(21) In order to exert the force or torque on the resilient element 5, the spring part of the preloading means 6 comprises a first elongate movable element 22, connected to the flexible blade 11 and disposed in the continuation thereof. A first pair of parallel flexible blades 24 connects the first movable element 22 to a second stationary support 23 to form a translation stage and guide the displacement of the first movable element 22.

(22) The spring part comprises a second pair of parallel flexible blades arranged on the same side as the first pair of parallel flexible blades 24, and connects the first movable element 22 to a second movable element 28.

(23) The second movable element 28 is laterally connected to the thermally deformable body 15 by a second flexible blade 21 substantially parallel to the first movable element 22 when the regulating member 10 is in the rest position.

(24) In this embodiment, the deformable body is preferably also a bimetallic attachment arranged perpendicular to the second flexible blade 21 and to the first movable element 22. The second flexible blade 21 is connected to the tip of the free part of the bimetallic attachment, the latter end of the bimetallic attachment being held by a fixed support 29 at the base thereof.

(25) Thus, when the bimetallic attachment bends or straightens, the second flexible blade 21 transmits a displacement to the second movable element 28, which transmits it to the first movable element 22 via the second pair of parallel flexible blades 25. The first movable element 22 is guided by the first translation stage to transmit the force or torque to the resilient element through the first flexible blade 11.

(26) In a similar way to the first embodiment, the temperature variation will cause the thermally deformable body 15 to deform, and the stiffness of the resilient element 5 to change, and thus the rate of the regulating member to change.

(27) A third pair of parallel flexible blades 26 connects the second movable element 28 to a third movable element 27. The third pair of parallel flexible blades 26 and the third movable element 27 are arranged in series with the second pair of parallel flexible blades 25 and the second movable element 28.

(28) Regulating means, such as a screw, can be added to exert a force 59 on the third movable element 27. Increasing the force 59 causes the displacement of the bimetallic attachment to be transmitted to a lesser degree to the first movable element 22, and decreasing the force causes the displacement of the bimetallic attachment to be transmitted to a greater degree to the first movable element 22. The regulating means allow the sensitivity of the preloading means 6 to be regulated as a function of temperature.

(29) The invention further relates to a horological movement, not shown in the figures, the movement comprising a rotary regulating member 1, 10 as described hereinabove.

(30) It goes without saying that the invention is not limited to the embodiments described with reference to the figures and alternatives can be considered without leaving the scope of the invention.