CH706274A2 - Escapement mechanism for clockwork movement of timepiece, has single-piece flexible mechanism transmitting pulses between balance and escapement wheel and connected to fixture structure of timepiece or wheel by flexible blade - Google Patents

Abstract

The mechanism (100) has a single-piece flexible mechanism (500) transmitting pulses between a balance (300) and an escapement wheel (400). The mechanism has a sensor co-operating with the escapement wheel or the balance. The single-piece flexible mechanism is connected to a fixture structure of timepiece or to the escapement wheel by a flexible blade. The mechanism has an anchor or a constant force flexible bistable buckling Swiss lever. The anchor includes a rod provided with a fork with spur and a flexible rod.

Description

Field of the invention

The invention relates to an escapement mechanism for movement or timepiece comprising at least one balance and at least one escape wheel.

The invention also relates to a watch movement comprising a fixed structure and at least one such mechanism.

The invention relates to a timepiece comprising a fixed structure and at least one such mechanism, and / or at least one such watch movement.

The invention relates to the field of watch mechanisms, and in particular exhaust mechanisms.

Background of the invention

[0005] The watchmaking performance requires movements of high precision, with minimal bulk, and a small number of components, so as to control the costs of production, assembly and adjustment. "LIGA" or "DRIE" technologies make it possible to produce flexible and precise components, and to completely call into question traditional architectures, characterized by a large number of components and delicate adjustments.

Summary of the invention

The invention proposes to overcome the limitations of known architectures, providing compact mechanisms, thin, and economical to produce.

For this purpose, the invention relates to an escapement mechanism for movement or timepiece comprising at least one balance wheel and at least one escape wheel, characterized in that the pulse transmission between said at least one a rocker arm and said at least one escape wheel is made by a one-piece flexible mechanism comprising at least one probe cooperating with said at least one escape wheel or said at least one rocker respectively, and in that said one-piece flexible mechanism is connected by at least one flexible blade to a fixed structure of said timepiece, or respectively to said at least one escape wheel.

The invention also relates to a watch movement comprising a fixed structure and at least one such mechanism.

The invention relates to a timepiece comprising a fixed structure and at least one such mechanism, and / or at least one such watch movement.

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 accompanying drawings, in which: figs. 1 to 4 show, schematically and in elevation, flexible guides, linear in FIGS. 1 and 2, angular in FIGS. 3 and 4, and successively represented in the state at rest and in a state excited by a pulse force; fig. 5 is a similarly flexible bistable pivot; fig. 6 shows schematically and in plan, a centering means 60 figs. 7 to 10 illustrate a flexible Swiss anchor with constant force, bistable buckling, and FIG. 10 is a descriptive graph of the variation of potential energy of the mechanism, according to the different intermediate states shown in FIG. 9; fig. 11 illustrates an escape mechanism 110 with a zero rigidity guide; fig. 12 shows a spiral escapement mechanism, and FIG. 13 is a detail of the associated escape wheel; figs. 14 and 15 illustrate an escapement without anchor; figs. 16 to 25 illustrate different variants that can be used for carrying out such flexible mechanisms: the structure of FIG. 16comporte two leaf-spring in two orthogonal planes, and connecting two structures at right angle; the structure of FIG. 17 is a structure of the RCC (Remote Center Compliance) type with a mass suspended by two leaf springs at right angles to a fixed structure having perpendicular anchoring faces; the first structure of FIG. 18comporte a movable mass connected to a fixed anchor by two parallel spring blades, and the second structure comprises a movable mass connected to a fixed anchor by two spring blades at right angles to one another; the structure of FIG. 19, similar to the first structure of FIG. 18, shows a parabolic type translation under the effect of an additional lateral mass at right angles to the moving mass; the structure of FIG. 20comporte parallel blades with hinges circular type; fig. 21 illustrates the deformation of the second structure of FIG. 18; the structure of FIG. 22comporte a mobile mass relative to a fixed anchor, which it is connected by two leaf-spring together constituting a cross structure; fig. 23 is a variant of FIG. 17, wherein the moving mass is square, substantially parallel to the perpendicular anchoring faces; figs. 24 and 25 illustrate a bistable system with pre-stress by a load spring which strongly constrains the flexible system, FIG. 25 being a relative stiffness curve as a function of the force applied; fig. 26 represents, in the form of a block diagram, a timepiece with a movement comprising such a mechanism.

Detailed Description of the Preferred Embodiments

Many watch mechanisms can be realized with a reduced number of components, and preferably using components made of silicon, or a LIGA or DRIE process, including flexible zones.

These flexible zones can be used to carry out guidance, especially pivoting, and / or to achieve elastic return means. In the remainder of the description, "flexible guides" are termed linear or rotary guides comprising one or more flexible blades. Their advantages are numerous, and one will quote in particular: precision, absence of friction, absence of hysteresis, absence of wear, no need of lubrication, absence of seizing, monolithic manufacture. The most frequent limitations are: limitation of displacements, weak intensity of forces or restoring torques, sometimes complex kinematics, limitation of the supported load. Figs. 1 to 4 illustrate such flexible guides. They are linear in figs. 1 and 2 where a mobile mass 11 is suspended relative to a fixed anchor 12 by means of a set of spring blades 13 substantially parallel to each other interposed, on the one hand between the fixed anchor 12 and an intermediate mass 14, and secondly between the intermediate mass 14 and the moving mass 11, FIG. 1 represents the system at rest, and FIG. 2constrained stress on the moving mass; the linear displacement of the intermediate mass 14 is here half of the displacement of the moving mass 11. Similarly, FIGS. 3 and 4, at rest and under stress, illustrate a similarly constructed rotary guide, but where the blades 33 develop radially about a virtual pivot axis A; the angular displacement of the intermediate mass 34 is half of the displacement of the mobile mass 31.

The flexible guides can be modified to have a zero rigidity or to have a bistable state in the case of a component working in buckling under the action of forces exerted on both sides "of a mean direction, on either side of which this component can occupy two different stable states. Figs. 24 and 25 illustrate such a bistable system which can be: - is rigid in the absence of load spring; - bistable if a load spring R strongly constrains the flexible system; - Zero rigidity if a load spring R forced an intermediate value guiding, as shown in FIG. Where the relative stiffness curve passes through the zero value for a load value corresponding to that of the pre-stress due to the spring R.

A first watch application relates to a bistable flexible pivot 50, as visible in FIG. 5, and which can be implemented as guidance of an anchor, or Swiss anchor, or another watchmaking element. The application of a force F on the flexible pivot 50, at a moving mass 51, creates a bistable behavior. This force can be created by a flexible spring. As in figs. 3 and 4, sets of radial leaf springs 53 couple in pairs a fixed anchor 52, an intermediate mass 54, and the moving mass 51. It can be seen that the virtual pivot axis A and the moving mass 51 can, according to the need, be on the same side of the fixed anchor as in fig. 3, either side of it as in FIG. 5.

Another application visible in FIG. 6concerne a centering means 60, in particular silicon or the like, acting as a stone for centering an axis 61, with a plurality of elastic fingers 62. Such a flexible element overcomes the problem of frolicking in the pivots. Such flexible centering fingers 62, in particular silicon, are not strictly speaking flexible guides because they are in constant friction with the axis 61 which they ensure the centering. The integration of stops 63 makes it possible to avoid any breakage of the flexible elements 62.

In a particularly advantageous manner, the invention is applicable to an exhaust mechanism 100 for movement 900 or timepiece 1000 comprising at least one balance wheel 300 and at least one escape wheel 400.

According to the invention, the transmission of pulses between said at least one balance wheel 300 and said at least one escape wheel 400 is formed by a one-piece flexible mechanism 500. This flexible one-piece mechanism 500 comprises at least one probe 600 for cooperation with said at least one escape wheel 400 or respectively said at least one rocker 300. This flexible one-piece mechanism 500 is connected by at least one flexible blade 700, or preferably by a plurality of flexible blades constituting return means elastic, to a fixed structure 800 of said timepiece 1000, or respectively to said at least one escape wheel 400.

An interesting application relates to an anchor, in particular a flexible Swiss anchor constant force, as shown in Figs. 7 to 10, which works according to the bistable principle in buckling. The anchor 70 comprises a rod 71 provided with a fork 72 with dart (not shown in the figures) similar to a Swiss anchor. The anchor 70 has a flexible rod 73 which pivots at 74 and is guided at 75 (rotation and vertical translation). A displacement Δx of the guidance at 75 induces a permanent bistable state. The anchor 70 cooperates with a two-level escapement wheel, represented here only by pins 77, 78, which it comprises on these two respective levels.

An ankle 76, on a second level of the anchor 70, allows the escape wheel to move the anchor 70 near its tipping point.

The race of the anchor 70 is limited by pins or limit stops 79, 80.

The pendulum and small and large trays, not shown, are similar to those of a classic Swiss anchor.

FIG. 10 is a descriptive graph of the variation of potential energy of the mechanism, where the flexible anchor 70 is represented by a ball 81 which rolls on a bump of potential energy 82. The stroke is limited by the pins 79 and 80. The operation is explained for a movement in the direction S1 of the fork 72, corresponding to the direction S2 of the flexible rod 73, according to the different intermediate states shown in FIG. 9 and symbolized in FIG. 10.

Step P1 corresponds to the recharge of the constant force. This state is of very short duration, because the escape wheel pushes, via its pegs, to the position P2, where the anchor 70 is just before the bistable tilting point.

The passage from the P2 position to the P3 position corresponds to the release of the anchor 70. The pendulum plate pin rocker anchor 70 on the other side of the bistable state.

The passage from the position P3 to the position P4 corresponds to the impulse phase of the anchor 70 on the balance: the rod 73 of the anchor 70 carries the pulse with a constant force; indeed, only the energy stored in the rod 73 is restored.

In the P4 position, the balance is free, the plateau pin leaves the fork 72, and the oscillator is completely free.

The transition from the P4 position to the P5 position corresponds to the release of the escape wheel: the anchor rod 73 ends to bend, and it emerges from the escape wheel, this without influencing the movement the balance that is already free.

The transition from the position P5 to the position P6 corresponds to the return: the escape wheel advances a tooth pitch, and brings the anchor 70 in the position P6, where the anchor 70 is ready to accommodate the plateau pin for a new cycle.

The system can not create a pulse during an impact because the dart, not shown in the figures, prevents overturning. The system has all the security features of a Swiss lever escapement.

Another application is illustrated in FIG. 11, and relates to an exhaust mechanism 10 with a zero rigidity guide. This mechanism 110 comprises a movable frame 111 articulated by flexible blades 113 relative to fixed anchors 112. The movable frame 111 comprises a load spring giving it a zero rigidity, as described above. This mobile frame 111, which is the equivalent of an anchor, carries a fork 114 with horns 115 and a dart 116. This fork 114 is similar to that of a Swiss anchor, with all the anti-rebate and anti security -gallop. An escape wheel 118 has teeth 118A, B, C, D, arranged at 90 ° from each other, which can cooperate with teeth 118A, B, C, D, of the movable frame 111, also arranged at 90 °. each other. The pendulum and the small and large trays are similar to those of a classic Swiss anchor.

When the plate pin 117 comes into contact with the input horn, a tooth 119A of the movable frame 111 releases without recess the escape wheel 118, and the tooth 118B of the escape wheel 118, substantially to the square of the tooth 119A, makes a tangential pulse on the movable frame 111 of the anchor at a tooth 119B. At the end of the pulse, the tooth 118C of the escape wheel is stopped by the corresponding tooth 119C on the anchor. The pulse cycle reproduces similarly with teeth 118D and 119D.

In a similar manner to the previous system, a larger load of the flexible blades 113 can create a bistable system. The position of the pulse tooth 118B with respect to the tooth 119A can bring the anchor near the instability, similarly to the position P2 in FIG. 9. As a result, the anchor 111 provides a pulse via the escape wheel 118 and the energy stored in the flexible blades 113.

The system has all the security of the Swiss anchor escapement.

FIG. 12 shows a spiral escapement mechanism 120.

The principle of maintenance and regulation of the oscillator of this exhaust is very different from the conventional approach. The pendulum is no longer equipped with trays and the maintenance of the oscillation is carried out via the stud and the hairspring.

The spiral spring 121 spiral ends with a pin 122, which is movable during operation. This stud 122 is guided by a flexible guide 123, with flexible blades 124, and whose center of rotation 125 corresponds to the axis of the balance. On this pin 122 is fixed ankle 127.

The escape wheel 126 has no teeth but a path 128, or cam, which is housed the peg 127 of pin, as shown in FIG. 13. This path 128 comprises a succession of ramps 128A, 128B, oblique with respect to the radial of the escape wheel, separated by rest positions, and having the appearance of a toothed wheel centered on the axis of the escape wheel, the ramps 128A and 128B being alternately increasing and decreasing when one traverses the periphery of the escape wheel 126.

The balance does not have a plateau, and is greatly simplified.

If one imagines the behavior of the mechanism without peg pin and without escape wheel: in this case, during oscillations, the bolt 122 moves relative to its rest position under the action of the force that exerts the spiral 121 on him. However, the system stops for lack of maintenance. In the case of the complete system, the pin anchor 127, guided in the profile 128, performs the function of maintenance and regulation of the oscillation in the following manner, described during a time displacement of the pendulum in motion: When the balance is in the position corresponding to FIGS. 12 and 13, the pendulum beginning its clockwise movement, the peg pin 127 blocks the pivoting of the escape wheel 126. The pin 127 can not move in the direction SD, because the hairspring 121 holds it to the left; - When the balance and the peg are in the rest position, during the clockwise rotation of the balance, just after passing through the rest position of the spiral121, the pin 122 is driven by the pendulum. The peg 127 is disengaged from its rest 129 in the escape wheel 126, and a counterclockwise pulse recharges the hairspring 121; When the pendulum is at the end of the hourly stroke, the peg pin 127, once arrived at its next rest point 129A on the escape wheel 126, will not come out of it, because the pendulum continues to hold it in the opposite.

Figs. 14 and 15 illustrate an escapement without anchor 140. The rocker 141 comprises a plate with a pin 142. The plate comprises two pins / stops 143 and 144. An escape wheel 145 has a plurality of teeth 146. Each tooth 146 fulfills the function of a small anchor, and includes a mini-anchor 147: Each mini-anchor 147 comprises an anchor pin 148 guided by flexible blades 149. This anchor pin 148 can be actuated by a small lever 150. Each tooth 146 also comprises a pulse plane 151. The escape wheel mechanism is at two levels: a low level carries the anchor pins 148, and corresponds to the level at which the pins / stops 87 and 144 are arranged, while a high level carries the escape wheel structure 145 and the levers 150.

The operation is explained on a tooth 146 of the escape wheel 145 just after a pulse, the rocker 141 starting a time shift. During the rotation of the rocker 141 in the clockwise direction, the plate pin 142 rotates the mini-anchor 147, which passes from the position PB to the position PA of FIG. 15, and disengages from the first pin / stop plate 143. The escape wheel 146 advances a very small angle until the anchor pin 146 of the mini-anchor 147 abuts against the second pin / platinum stop 144.

When the rocker 141 pivots counterclockwise, the plate pin 142 rotates the mini-anchor 147 facing it, bringing the lever 150 to the PC position, and the anchor pin 148 bypasses the second peg The stop wheel 145 rotates to the next tooth. In this movement, the pulse plane 151 of the escape wheel 145 pulses on the plateau pin 142.

The special shape of the pins / stops 143 and 144 integral with the plate avoid galloping. Figs. 16 to 25 illustrate different variants that can be used for carrying out such flexible mechanisms: The structure 160 of FIG. 16comporte two spring blades 161 and 162 in two orthogonal planes, and connecting two structures at right angles 163 and 164; The structure 170 of FIG. 17is a remote center compliance (RCC) type structure with a mass 171 suspended by two leaf springs 172 and 173 square to a fixed structure 174 having perpendicular anchor faces 175 and 176; The first structure 180 of FIG. 18 comprises a movable mass 181 connected to a fixed anchorage 182 by two parallel spring blades 183 and 184, and the second structure 185 comprises a movable mass 186 connected to a fixed anchorage 187 by two leaf springs 188 and 189 to the square one from the other; the structure 180 of FIG. 19, similar to the first structure 180 of FIG. 18, shows a parabolic type translation under the effect of an additional lateral mass 181A at right angles to the moving mass 181, with a value λ = 0.6 X <2> / L; The structure 200 of FIG. 20 comprises parallel blades with hinges of circular type, if the dimensioning of the radius R is less than 5 times the value of the minimum thickness Hmin, the stress concentration effects are negligible; - fig. 21 illustrates the deformed second structure 185 of FIG. 18; The structure 220 of FIG. 22 comprises a movable mass 221 relative to a fixed anchor 222, to which it is connected by two leaf springs 223 and 224 together constituting a cross structure; - fig. 23 is a variant of FIG. 17, where the moving mass 171 is square, substantially parallel to the anchor faces 175 and 176 perpendicular; - figs. 24 and 25 illustrate a bistable system with pre-stressing by a load spring R which strongly constrains the flexible system by buckling, FIG. 25 being a curve of relative rigidity as a function of the force applied.

The invention also relates to a timepiece 900 comprising at least one of the flexible mechanisms described above, and in particular having a fixed structure 800 and at least one such mechanism 100.

The invention also relates to a timepiece 1000, including a watch, comprising at least one such watch movement 900, and / or at least one of the flexible mechanisms described above, including a fixed structure 800 and at least one such mechanism 100.

Claims (7)

1. Exhaust mechanism (100) for movement (900) or timepiece (1000) comprising at least one balance (300) and at least one escape wheel (400), characterized in that the transmission of pulses between said at least one balance (300) and said at least one escape wheel (400) is provided by a one-piece flexible mechanism (500) comprising at least one probe (600) for cooperation with said at least one wheel of exhaust (400) or respectively said at least one rocker (300), and in that said monobloc flexible mechanism (500) is connected by at least one flexible blade (700) to a fixed structure (800) of said timepiece (1000), or respectively to said at least one escape wheel (400). 2. Mechanism (100) according to claim 1, characterized in that said monobloc flexible mechanism (500) is an anchor (70), or a Swiss anchor, flexible constant force, bistable buckling, said anchor (70) having a rod (71) provided with a fork (72) with dart and having a flexible pivotable and guided rod (73), said anchor (70) cooperating with a two-level escapement wheel (400) having pins (77). 78) on said two respective levels, said anchor (70) still carrying, on another level than said flexible rod (73), a pin 76, arranged to cooperate with said escape wheel (400) for the displacement of said anchor (70) near its tipping point. 3. Mechanism (100) according to claim 1, characterized in that it constitutes an exhaust mechanism (110) with a zero rigidity guide, said mechanism (110) comprising a movable frame (111) articulated by flexible blades (113) relative to fixed anchors (112), said movable frame (111) has a load spring giving it zero rigidity, said movable frame (111) constituting an anchor and carrying a fork (114) with horns (115) and a dart (116), said fork 114 being similar to that of a Swiss anchor, said mechanism (100) having an escape wheel (118) having teeth (118A, B, C, D) arranged to cooperate with teeth (119A, B, C, D) of said movable frame (111), said mechanism (100) comprising a balance (300) equipped with small and large trays similar to those of a Swiss anchor and carrying a plateau pin (117), said mechanism (100) being arranged so that when the adite plate pin (117) comes into contact with an input horn (115), a tooth (119A) of said movable frame (111) releasably releases said escape wheel (118), and a tooth (118B) of the escape wheel (118) in a position substantially perpendicular to said tooth (119A) makes a tangential pulse on said movable frame (111) of the anchor, and that, at the end of the pulse, a tooth (118C ) of said escape wheel (118) is stopped by a corresponding tooth (119C) of said movable frame (111). 4. Mechanism (100) according to claim 1, characterized in that it constitutes a spiral escapement mechanism (120), with a balance (300) devoid of trays, and where the maintenance of the oscillation is performed via a pin and a spiral spring (121) which ends with a pin (122) which is movable during operation and which is guided by a flexible guide (123) with flexible blades (124), and whose center of rotation (125) corresponds to the axis of said beam (300), on said pin (122) being fixed an ankle (127), said mechanism (100) comprising an exhaust wheel (126) without teeth but having a cam path (128) which accommodates said peg pin (127), said mechanism (100) being arranged such that, during oscillations, said peg (122) moves relative to its position of resting under the action of the force exerted on him said hairspring (121), and that said peg pin (127) ), guided in said profile (128), performs the function of maintenance and regulation of the oscillation, so that during a time displacement of the pendulum in motion: - When the balance is in a first position where it starts its clockwise movement, said peg pin (127) blocks the pivoting of said escapement wheel (126), said pin (127) being retained by said hairspring (121); - When the balance and the peg are in the rest position, during the clockwise rotation of the balance, just after the passage through the rest position of the hairspring (121), said peg (122) is driven by the balance, and said pin (127) disengages from its rest (129) in said escape wheel (126), and a counterclockwise pulse reloads said balance spring (121); When the balance is at the end of the hourly stroke, said peg pin (127), once arrived at a next rest point (129A) on said escape wheel (126), remains there, being retained by the balance in the opposite direction. 5. Mechanism (100) according to claim 1, characterized in that it constitutes an escapement mechanism without anchor (140), with a rocker (141) having a plate with an ankle (142), a plate (800) having two plugs / stops (143; 144), and an escape wheel (145) having a plurality of teeth (146), each having a mini-anchor (147), which includes a guided anchor pin (148) by flexible blades (149), said anchor pin (148) being actuated by a lever (150), and each said tooth (146) also having a pulse plane (151), said wheel having two levels, a low level carrying said anchor plugs (148), and corresponding to the level at which said plugs / stops (143; 144) are disposed, and a high level carrying an escape wheel structure (145) and said levers ( 150), said mechanism (100) being arranged so that, when, just after an impu lsion, said rocker (141) beginning a time displacement, during the rotation of said rocker (141) in the clockwise direction, said plateau pin (142) rotates said corresponding mini-anchor (147), which emerges from said first pin / platinum stop (143), said escape wheel (146) then advancing at a very low angle until said anchor pin (148) of said mini-anchor (147) abuts said second pin (144), and that when said rocker (141) pivots counterclockwise, said plate pin (142) pivots said facing mini-anchor (147), causing its lever ( 150) facing said first pin / platinum stop (143, and said anchor pin (148) bypassing said second pin / platinum stop (144), said escape wheel (145) rotating to the tooth ( 146) during this movement, said pulse plane (151) impulsing said plateau pin (142). 6. Watch movement (900) comprising a fixed structure (800) and at least one said mechanism (100) according to one of the preceding claims. 7. Timepiece (1000) comprising a fixed structure (800) and at least one said mechanism (100) according to one of claims 1 to 5, and / or at least one watch movement (900) according to the preceding claim .