Classifications

• • G—PHYSICS
  • G04—HOROLOGY
  • G04B—MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
  • G04B15/00—Escapements
  • G04B15/06—Free escapements
• • G—PHYSICS
  • G04—HOROLOGY
  • G04B—MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
  • G04B15/00—Escapements
  • G04B15/14—Component parts or constructional details, e.g. construction of the lever or the escape wheel

Definitions

• the present invention relates to the field of watchmaking. It concerns an escape mechanism and, more particularly, a free escape mechanism with direct impulses.
• the exhaust is an essential part of mechanical watch movements. It is usually placed between a cog and an oscillator.
• the train transmits to the exhaust a torque coming from the energy source, which maintains and counts oscillations of the oscillator.
• the relaxation exhaust is the one of the two which has the best energy efficiency.
• Various examples of expansion exhausts are for example described in documents CH 704 151 B1, EP 1 538 491 A1 or EP 1 710 636 A1.
• detent escapements are sensitive to high acceleration and shock with significant risks of galloping and tripping. As a result, the detent escapement is not widespread because it supports to be worn and difficult to mate with the high frequency oscillators, which tend today to prevail because of their better accuracy.
• the anchor escapement does not know these risks but has the disadvantage of a higher energy consumption due to more shocks, inertia and greater friction at the anchor.
• the present invention aims to overcome the aforementioned drawbacks by providing an exhaust that is compatible with strong accelerations of a high-frequency oscillator and the constraints of wrist-carrying while maintaining low power consumption. Disclosure of the invention
• the invention relates to a free escapement mechanism blow for timepiece as defined in claim 1, said timepiece comprising:
• a gear train intended to be driven by a drive member and comprising a mobile gear wheel movable in rotation about an axis of rotation and arranged in kinematic connection with at least one escape wheel of the exhaust mechanism, an oscillator adapted to receive a pulse of said escape wheel to maintain its oscillations.
• the escape mechanism of the invention further comprises:
• a release wheel arranged to co-operate in rotation with the escape wheel and to move, during a disengagement phase, under a pulse of the oscillator, between an engagement position in which the advance of the gear train is blocked and a release position in which the advance of the gear train is free, and
• a unidirectional drive device of the disengagement movable arranged to transmit said pulse of the oscillator to the disengagement movable from the engagement position to the disengagement position.
• the escapement mechanism of the invention is designed such that the release mobile and the unidirectional drive device are arranged to cooperate with means configured to accumulate a portion of the energy supplied by a pulse of the oscillator during the release of the disengagement mobile on the one hand and to restore it in the form of an acceleration of the escape wheel during a transmission by the escape wheel of a pulse to the oscillator on the other hand.
• the dependent claims provide other particular features of the exhaust mechanism of the invention.
• the release mobile and the cog wheel are arranged relative to each other so that there is a draw or negative between the two.
• the cog wheel and the disengagement wheel are arranged so that said portion of energy transmitted by the oscillator during the disengagement phase is accumulated in elastic form before contributing to the acceleration. of said escape wheel.
• the escape mechanism comprises a positioning stop adapted to position the release member in the engagement position, said stop being optionally fixed with reference to the axis of rotation of the mobile. clearance.
• the axes of rotation of the cog wheel, the escape wheel and the disengagement wheel are parallel and coplanar.
• the oscillator is rotatable about an axis and in that the axes of rotation of the oscillator, the cog wheel, the escape wheel and the release mobile. are parallel and coplanar when the engagement mobile is in the engagement position.
• the unidirectional drive device comprises a plurality of flexible blades each arranged in abutment on a ratchet stop, said flexible blades and ratchet stops being arranged radially in a regular angular distribution.
• the unidirectional drive device is integral with the release mobile or the oscillator.
• the release mobile is coaxial with the escape wheel.
• the exhaust mechanism comprises an elastic member, in particular a return spring, mounted between the release wheel and the escape wheel, and which tends to bring the mobile clearance in its engagement position, preferably against the positioning stop in the engagement position.
• the release mobile has idle pins, in that the cog wheel has rest pins, in that the trajectories of the rest pins and rest pins are intersecting and in that the mechanism is arranged so that the resting studs meet the rest pins by causing the stop of the gear train when the engagement wheel is in the engagement position.
• the unidirectional drive device is integral with the escape wheel.
• the escape wheel is mounted movably on the release wheel and the escape wheel has rest teeth intended to bear against a fixed rest pallet with reference to the frame of the d-piece. watchmaking.
• the mobile release is also advantageously consists of a rocker pivoted on the axis of the moving wheel.
• FIGS. 1 to 6 show a first embodiment of a turboexhaust escapement mechanism according to the invention
• FIG. 1 represents a perspective view of the first embodiment
• FIGS. 2 to 6 provide chronological views of the assembly of Figure 1, at different stages of its operation
• FIG. 7 represents a perspective view of a second embodiment of the invention
• Figures 8 to 12 provide chronological views of the assembly of Figure 7, at different stages of its operation.
• the springs of the trigger rockers are designed to exert a low restoring force.
• the increase in this restoring force would reduce the impact sensitivity and support high frequencies by accelerating the return of the rocker in its rest position but would have the disadvantage of increasing the energy consumption during the release.
• the present invention implements a particular escape mechanism in which one seeks to recover the energy necessary for the release rather than to reduce it. Like any escapement trigger, this mechanism has a single rest position, the release and the impulse occur alternately out of two, the other being a lost shot.
• FIG. 1 A first embodiment of an exhaust mechanism according to the invention is shown in Figures 1 to 6.
• the mechanism comprises a cog wheel 1 kinematically connected to an escape wheel 2 and forming with it a gear driven by a motor member not shown, typically a cylinder.
• the escape wheel comprises pulse teeth 3 for periodically giving a pulse to an oscillator here taking the form of a rocker of which only the plate 4 and the pin 5 are shown.
• the moving wheel 1 comprises resting studs 6 arranged in a circle at the end of radially extending arm.
• the exhaust mechanism further comprises a release wheel 7 in the form of a wheel pivoted on the same axis as the wheel exhaust.
• the release mobile 7 comprises idle pins 8 and a unidirectional drive device formed by flexible blades 9 extending radially and bearing against ratchet stops 10 in their rest position.
• the ratchet stops 10 are adjacent to the rest pins but could be otherwise as will be discussed later.
• the angular amplitude of the rotation of the disengagement wheel 7 with respect to the escape wheel 2 is limited by a positioning abutment 1 1 secured to the disengagement wheel 7.
• a return spring 12 disposed between the escape wheel 2 and the release member 7 tends to bring the release member 7 into an angular position defined with reference to the escape wheel 2.
• FIG. 2 represents the exhaust mechanism at rest, the rocker having just traveled freely through the supplementary arc and the pin 5 preparing to come into contact with a flexible blade 9 of the release mobile 7.
• the wheel is at the stopping, a rest pin 6 of the wheelhouse being in abutment against a rest pin 8 of the disengagement wheel 7.
• FIG. 3 shows the escape mechanism during the disengagement phase during which the disengaging wheel 7 moves from an engagement position to a disengagement position under the impulse of the beam transmitted by means of the blade.
• flexible 9. The flexible blade 9 is in abutment against the pawl stopper 10 by forming a pawl mechanism so that the pulse of the balance causes the rotation of the disengagement device 7 in the counterclockwise direction as shown in the figures.
• the bearing surfaces of the rest pin 6 and the rest pin 8 slide against each other.
• the contact surfaces of the rest pins 8 are circular base cylinder portions coaxial with the pivot axis of the disengagement wheel 7 so that the disengagement of the disengagement wheel 7 does not cause in advance This configuration corresponds to a draw angle of zero.
• the surface of the idler pins could have a positive pulling angle to secure the locking of the release wheel 7 or on the contrary a negative draft angle to facilitate its release.
• the wheel set 1 is impeded in its rotation and does not transmit engine torque to the escape wheel 2 which remains in its waiting position .
• the release wheel 7 pivots with reference to the escape wheel 2 and the return spring 12 accumulates, in elastic form, kinetic energy from the beam.
• the flexible arms 9 and the rest pins 8 are arranged radially in a regular angular distribution so that the release member 7 is balanced on its axis of rotation and, therefore, insensitive to accelerations suffered by the timepiece. Furthermore, the return spring 12 tends to keep the release member 7 abuts against the escape wheel 2 in its engagement position. Thus it is not necessary to provide a positive draft angle to further secure the release mobile 7 which minimizes the disturbances caused to the oscillator during release.
• Figure 4 shows the escape mechanism in the pulse phase.
• FIG. 5 shows the escape mechanism at the end of the impulse phase and immediately before the stoppage of the wheelwork caused by the meeting of a resting stud 6 with a rest pin 8.
• Circular trajectories resting studs and idlers are secant and the mechanism is arranged for a stud 6 meets a pin 8 when the release mobile 7 is in the engagement position, that is to say when the wheel exhaust 2 has caught the release mobile 7, the positioning abutment 1 1 bears against the escape wheel 2. Therefore, the advance of the train is limited when the release mobile is in the engagement position .
• Figure 6 shows the exhaust mechanism at rest at the time of the blow lost during the next alternation.
• the rocker pivots counterclockwise and the pin 5 spreads the flexible arm 9 without rotating the release member 7.
• the flexible blade 9 constitutes with the ratchet stop 10 a ratchet-type unidirectional drive system.
• the back of the pulse teeth has a circular profile matching the shape of the balance plate to prevent accidental recoil of the escape wheel while the pendulum traverses the additional arc.
• the wheel is driven by a dual motor: the motor that propels the wheel in a conventional manner, and the return spring 12 which tows the escape wheel 2 when it starts.
• the action of the return spring 12 is more effective than it is fixed on the release mobile 7 which is itself rotated by the oscillator.
• a portion of the energy contributing to the acceleration of the train comes from the oscillator which goes against the generally accepted idea that we must avoid braking the oscillator so as not to disturb its isochronism and limit consumption energy.
• the transfer of energy from the oscillator to the wheel is optimized thanks to movable release 7 and the return spring 12 which acts as a damper and limits the loss of energy at the time of impact of the ankle on the flexible arm.
• the acceleration of the wheel is therefore given smoothly but as it is stronger than that which would be given by a single drive member, the time required for the escape wheel 2 to catch the pin 5 of the balance is reduced.
• the device can operate at higher frequencies but also that the pulse angle traveled by the pendulum in the pulse phase is greater.
• the stop of the gear is caused by the meeting of two movable elements with reference to the frame, kinematically linked in a discontinuous manner.
• the release mobile pivots always in the same direction which is also that of the given pulse by the oscillator as well as that of the displacement of the escape wheel.
• the energy accumulated in elastic form at each release in the return spring is restored when starting the escape wheel.
• the recovery of a part of the energy taken from the oscillator in the release phase characterizes a new type of exhaust that can be designated by the term "turbo-relaxation", which presents interesting performances. in terms of energy efficiency as well as frequency and dependability.
• the balance plate comprises a peg which makes the release and a pulse pad, separate from the peg, arranged to receive the impulse of the escape wheel.
• the respective angular and radial positions of the ankle and the pallet with respect to the axis of the balance define the beginning of the release and momentum phases and the angular clearance and pulse speeds.
• the angular velocity of the escape wheel is higher than the speed reached by the escape wheel at the beginning of the pulse.
• the mechanism of Exhaust according to the invention can be arranged in such a way that the kinetic energy acquired by the disengaging wheel during the disengagement phase is at least partially restored and contributes to the acceleration of the wheel.
• the unidirectional driving device could be placed on the oscillator.
• the release mobile could be connected to the escape wheel by flexible elements.
• the release movement of the release mobile under the action of the oscillator could be likened to a rotation or any other path adapted to the release of the rest pins.
• These same flexible elements could also play the role of recall spring.
• Figures 7 to 12 show a second embodiment of an exhaust mechanism according to the invention.
• a cogwheel formed of a cogwheel 1 and an escapement wheel 2 kinematically connected to each other and a rocker of which the plate 4 provided with his ankle 5.
• the mechanism also comprises a unidirectional drive device consisting of a plurality of flexible blades 9 abutting on ratchet stops 10.
• the unidirectional drive device is here mounted integral with the escape wheel 2.
• the wheel exhaust is not pivoted on the frame of the timepiece but on the release mobile 7 which here takes the form of a rocker pivoted on the same axis as the mobile wheel 1.
• the mechanism also comprises a positioning stop 1 1 able to position the release member 7 in an engagement position in which the rotation of the escape wheel is limited.
• a positioning stop 1 1 able to position the release member 7 in an engagement position in which the rotation of the escape wheel is limited.
• Figure 9 shows the escape mechanism in the disengagement phase.
• the plate pin 5 has hit a flexible blade 9 resting on a pawl stop 10.
• the rotation of the escape wheel 2 being hampered by the pallet rest 13, it is composed of the release mobile 7 , the escape wheel 2 and the moving wheel 1 which is rotated in the counterclockwise direction about the pivot axis of the wheelhouse.
• the retreat of the gear train in the disengagement phase causes the re-arming of the motor unit so that the energy supplied by the oscillator during the release is stored in elastic form by the motor member before being restored to propel the wheel.
• the escape wheel 2 and the wheel are released.
• the train accelerates and the release wheel 7 returns to its position of engagement against the positioning stop 1 1.
• the rest plane of the pallet of rest is preferably an orthoradial plane with reference to the axis of rotation of the disengagement wheel which corresponds to a zero draw angle.
• the rest plane may have a different inclination or a non-rectilinear profile.
• FIG. 10 shows the escape mechanism in the impulse phase after the release mobile 7 has returned to its position of engagement in abutment against the positioning stop 1 1 and a pulse tooth 3 of the escape wheel 2 has caught the peg 5 of the pendulum.
• Figure 1 1 shows the mechanism at the end of the impulse phase and just before the stoppage of the gear caused by the meeting of the next impulse tooth 3 with the pallet rest 13.
• Figure 12 shows the mechanism at rest during the blow lost the return of the balance at the time of passage of the pawl.
• the energy provided by the oscillator during the release is at least partially restored to drive the gear train.
• this second embodiment directly uses the drive member to temporarily store, in elastic form, the energy from the oscillator during the release. It is also the driving force that keeps the release mobile 7 in the engagement position. Note that in the exhausts of the prior art, the gear back slightly back on release when the draft angle is positive, this provision for the purpose of securing the trigger and not to recover energy.
• the unidirectional drive device could comprise only one pawl and be integral with the release mobile or the oscillator.
• the release and impulse functions could be provided by separate teeth on the escape wheel and by separate palettes on the oscillator.
• the escape mobile could be translated rather than rotated. It could also be connected to the frame by a flexible element.
• the release mobile could comprise a counterweight so that the moving assembly that it composes with the escape wheel is balanced on its axis of rotation.
• the mechanism could comprise a second stop for limiting the amplitude of the movement of the disengagement wheel and a return spring to accelerate the return of the disengagement wheel in its engagement position.
• the mechanism could also include a safety device that would limit the movement of the disengagement wheel in the free oscillation phases of the oscillator.

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• General Physics & Mathematics (AREA)
• Transmission Devices (AREA)

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• 2016
  • 2016-09-07 EP EP16187711.3A patent/EP3293583A1/de not_active Withdrawn
• 2017
  • 2017-09-06 EP EP17761283.5A patent/EP3510449B1/de active Active
  • 2017-09-06 WO PCT/EP2017/072392 patent/WO2018046563A1/fr unknown

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