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
  • G04B31/00—Bearings; Point suspensions or counter-point suspensions; Pivot bearings; Single parts therefor
  • G04B31/004—Bearings; Point suspensions or counter-point suspensions; Pivot bearings; Single parts therefor characterised by the material used
  • G04B31/016—Plastic bearings
• • 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
  • G04B31/00—Bearings; Point suspensions or counter-point suspensions; Pivot bearings; Single parts therefor
  • G04B31/02—Shock-damping bearings
• • 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
  • G04B31/00—Bearings; Point suspensions or counter-point suspensions; Pivot bearings; Single parts therefor
  • G04B31/06—Manufacture or mounting processes

Definitions

• the present invention relates to a shock absorbing bearing for an axis of a mobile of a timepiece.
• the shaft comprises a beam, comprising a support, said support being provided with a housing adapted to receive a suspended pivot system in which the tigeron is inserted.
• the technical field of the invention is the technical field of fine mechanics.
• the present invention relates to bearings for timepieces, and more particularly to the type for damping shocks.
• Mechanical watch manufacturers have long designed numerous devices for absorbing the energy resulting from a shock by an axis of a mobile, by abutting against a wall of the hole of the base block through which it passes, while allowing a momentary movement of the tigeron before it is returned to its rest position under the action of a spring.
• FIG. 1 illustrates a shock absorbing device or shock absorbing bearing 1 comprising a support 2.
• This support has a housing 3 in which a pivoting system 4 is arranged, the purpose of which is to dampen, at least in part, sudden impacts. by the balance shaft 5.
• the pivot system 4 comprises elastic means 4a and a pivot module 4b.
• the elastic means are, in this example, in the form of a membrane.
• These elastic means are in the form of a base in the form of a disk comprising a lower face and an upper face and having a central orifice, the face bottom facing the bottom of the support that is to say the hole 6 in which the balance shaft terminated by a tigeron 5a passes.
• the pivot module In the center of this disc is fixed the pivot module.
• This disc comprises, at its periphery, a peripheral flange 4c extending in an axial direction, that is to say in a direction tending to move away from the upper face.
• this rim extends so that the surface of the horizontal plane to the disk increases as the height of the rim increases
• the pivot system 4 is placed on the bottom of the support and the flange of the elastic means is supported for example on a protrusion 2a of the support as shown in Figure 1.
• Such a pivot system is made of plastic so that it can be manufactured using injection and molding techniques.
• a disadvantage of such a shock absorber system is that it does not withstand shocks. Indeed, if the pivot does not break, the plastic is marked by the pivot. This marking of the plastic constituting the pivot system comes from the elastic part which has its Young's modulus which increases during the impact. However, the Young's modulus is also called modulus of elasticity (generally expressed in GPa) characterizes the resistance to the deformation of a material.
• the object of the invention is to overcome the disadvantages of the prior art by proposing to provide a shockproof timepiece system which has constant damping and friction characteristics.
• the invention relates to a shock absorbing bearing for an axis of a mobile of a timepiece, said axis comprising a tigeron, said bearing comprising a support provided with a housing provided to receive a means of suspended pivoting, said pivoting means is arranged to absorb, at least in part, the shocks suffered by the timepiece mobile, characterized in that the pivoting means is made of a metallic material and comprises a recess in which is inserted an insert made of a synthetic material and with which the tigeron cooperates.
• the insert is made of a polymeric material.
• the material of the insert is loaded.
• the polymer of the insert is chosen from the group comprising polyoxymethylene, polyamide, polyetheretherketone and polyphenylene sulfide.
• said pivoting means is a pellet comprising an annular part, a central part and elastic arms connecting the central part to the annular part, the central part comprising a recess so as to an insert with which the pivot can cooperate to rotate freely.
• the pivoting means comprises three resilient arms angularly offset by an angle of 120 °.
• the insert comprises a hole for insertion of the pivot, this hole consisting of an opening having a first straight or rectangular portion followed by a trapezoidal portion.
• the invention also relates to a method of manufacturing a shock-absorbing bearing of a mobile of a timepiece, said axis comprising a tigeron and a pivot, said bearing comprising a support provided with a housing adapted to receive suspended pivoting means, characterized in that said method comprises the following steps:
• said method comprises the following steps:
• FIG. 1 schematically shows a shockproof system of timepiece of the prior art
• FIG. 2 and 3 show schematically a shockproof timepiece system according to the invention
• FIG. 4 and 5 show schematically a shockproof timepiece system according to a variant of the invention
• the present invention proceeds from the general inventive idea of providing a shock absorbing or shockproof system having greater reliability and providing better positioning.
• the damping bearing or shockproof system 100 is shown in Figure 2, which illustrates a part of a timepiece provided with bearings according to the invention.
• the damping bearing 100 shown in Figure 2 comprises a frame comprising a support 103 in which a lower bearing 101 and an upper bearing 102 are mounted. These bearings 101, 102 are mounted in holes in said support 1 03.
• a mobile 105 which may be a rocker, is mounted on an axis 120 pivotally in these bearings. This axis 1 20 is provided at both ends with tibers 121 carrying pivots 122.
• the upper bearing 102 comprises an annular piece 127 in the form of a disc having an inner peripheral wall 128. This annular piece also comprises a flange 1 29 located on the disc surface and contiguous to the wall. This annular piece 127 is pierced with a central hole 130.
• the bearing 1 02 further comprises a pivoting means 126 'disposed in the housing formed by the peripheral wall 128 and the flange 129.
• the pivoting means 126' is placed on the rim 129 at its periphery so as to be suspended.
• This pivoting means 126 ' is fixed to the annular piece 127, for example by driving, gluing, latching or held by a ring. There is therefore a space between the pivoting means 126 ', and the bottom of the housing formed by the peripheral wall 128 and the flange 129.
• the pivoting means are therefore in contact with the support 101 only at the level of the fixing with this one. The fact of being suspended allows the pivot means 126 'to be able to refocus perfectly following a displacement due to a shock.
• the lower bearing 101 is identical in design to the upper bearing 1 02 that is to say it comprises an annular piece 124 in the form of a disk having a peripheral wall. This annular piece also comprises a rim located on the disk surface and contiguous to the wall. This annular piece 124 is pierced with a central hole 125.
• the bearing 102 further comprises a pivoting means 1 26 disposed in the housing formed by the peripheral wall and the flange in a suspended manner. This pivoting means 126 is fixed to the annular piece 124 for example by driving, gluing, latching or held by a ring.
• the dimensions of the lower bearing 101 will be smaller than those of the upper bearing 102 to show that the size of the bearing is easily adjustable and can be reduced.
• the dimensions of the upper bearing 1 02 and the lower bearing 101 may be identical.
• the lower bearing 101 or greater 102 including a first non-visible variant can be arranged so that the pivot means 126, 1 26 'is directly fixed in the support 103 by driving or gluing or welding or soldering.
• Said bearing 101, 102 may comprise a piece in the form of a ring which serves to hold the pivoting means 126, 26 'and a piece in the form of a disc having a peripheral rim and pierced in its center of a hole. This pierced disc shaped piece is used as a stop and its flange is used to provide a suspended system.
• the pivoting means 126, 126 ' is thus held radially by the walls of the hole made in the support and axially by the annular piece and the disc-shaped piece pierced.
• the pivoting means 126, 126 ', visible in Figure 3 are in the form of a pellet comprising a full annular portion 126a, a central portion 126b and elastic arms 126d. These arms 126d are wound substantially spirally so that they connect the central portion 126b to the annular portion 126a.
• the pivoting means 126, 126 ' comprise three arms 126d.
• the pivoting means 126 'of the upper bearing 102 are mounted in the annular part 127 of said upper bearing 102.
• the pivoting means 126, of the lower bearing 101 are mounted in the annular piece 124 inserted into the hole of the support 103.
• the central portion of the pivoting means 126, 126 ' has a recess 126e in which an insert 1260 is placed.
• This insert 1 260 is used so as to be provided with a hole 1261 in which the axle shank is inserted.
• This configuration makes it possible to have the pivoting means 1 26, 126 'in the form of a pellet comprising a full annular portion 126a, a central portion 126b and resilient arms 1 26d, which are made of a first material and insert 1260 which is made of a second material.
• the wheel is then pivotally mounted being engaged at its pivots 1 22 in non-through holes 1261 of the insert 1260 and at its tigger 121 in the holes of the support 103.
• This configuration allows the use of a specific material for the pivoting means 126, 126 'that is to say which is suitable for the damping function and a specific material for the insert that is to say a material suitable for a pivot function with a low coefficient of friction.
• the first material used for the pivoting means 126, 126 ' is a metallic material while the second material used for the insert 1260 is a synthetic material such as a plastic.
• This plastic material may be a polymer selected from the group consisting of polyoxymethylene, polyamide, polyetheretherketone, polyphenylene sulfide.
• the metals have a higher Young's modulus than for a plastic type material (for example the Young's modulus of Phynox (Cobalt Co + Chromium Cr + Nickel Ni + Molybdenum Mo) is 203 GPa, that of Titanium of 114 GPa, that of plexiglass of 2.38GPa and that of polyamide from 3 to 5 GPa).
• This difference in the value of the Young's modulus means that it is necessary to apply a higher stress for the metals so that they deform.
• the pivoting means 126, 126 'of metal will move less than the pivoting means 126, 126' of plastic.
• Metals also enable proven assemblies that are difficult to reconcile with polymers, especially by driving (no significant creep), welding or brazing (temperature).
• Another advantage of this choice of materials is that it makes it possible to have a more advantageous material for the pivot function. Indeed, the friction of a metal part on another metal part leads to heating and rapid wear of the pivot, lubrication is necessary to mitigate this heating.
• the plastic material of the insert 1260 is a charged polymer.
• charge is meant any inert, mineral or vegetable substance which, added to a base polymer, makes it possible to appreciably modify its mechanical, electrical or thermal properties or its appearance.
• the mobile 105 In the event of an axial impact, the mobile 105 is subjected to a force which is proportional to the acceleration undergone. This force is transmitted to the bearings by means of the pivots 122. The effect of this force and to deform the elastic arms 1 26d of the pivoting means 126, 126 'until the axis 120 of the wheel comes to take support, through its tigger 121, against the wall of the holes 1261. In this case, the wheel is then stopped by the axis 120 which abuts on the support 1 27, 124 serving as a stop. As the dimensions of the axis 120 are much larger than those of the pivots 122, the energy produced during the impact against the stop is thus transmitted to the axis 1 20 so as not to damage the pivots 122.
• the elastic arms 126d are dimensioned so that the tigger 121 come into contact with the annular parts as soon as an acceleration of about 500g is reached.
• the pivoting means 126, 26 ' are formed by three bent arms 1 26d whose attachment points, respectively to the annular portion 126a and the central portion 1 26b, are angularly offset by 1 20 degrees. It is obvious that the elastic function could be ensured with a different number of arms, or with other forms.
• the insert 1260 comprises a hole 1261 conical so that the end of the tigeron can be inserted to allow a difference in amplitude between the different positions of the watch minimized.
• This conical 1261 hole known from EP 2 142 965 consists of an opening having a first straight or rectangular portion that is to say having a straight or rectangular profile followed by a trapezoidal portion that is to say having a profile trapezoidal.
• the rounded tip of the pivot 122 is dimensioned so that its rounded surface can bear against the inclined edge of the trapezoidal profile portion.
• the invention also relates to a method of mounting such a shock absorbing bearing 100.
• a method consists in separately producing the pivoting means 126, 126 'and insert 1260.
• the insert 1260 is placed on the axis 120 at its two ends of tibernums 121 bearing pivots 122.
• This arrangement of the insert 1 260 serves to protect the pivots 122 so that the latter do not receive no shocks.
• the method consists of:
• the inserts 1260 are directly made on the axis 120.
• the pivots 122 of the axis 120 are placed in the molds used to make the inserts 1260.
• the synthetic material used for the inserts 1260 is then injected into the molds to form the inserts 1260.
• This variant is advantageous because it makes it possible to have the inserts 1260 and the pivots 122 of the axis 120 which cooperate perfectly.
• the method therefore consists of:

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Pivots And Pivotal Connections (AREA)
• Sliding-Contact Bearings (AREA)
• Vibration Dampers (AREA)
• Purses, Travelling Bags, Baskets, Or Suitcases (AREA)
• Electromechanical Clocks (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Publications (2)

Family

ID=49876367

Family Applications (2)

Family Applications Before (1)

Country Status (6)

Families Citing this family (7)

Family Cites Families (12)

• 2013
  • 2013-12-11 CH CH02054/13A patent/CH708936B1/fr unknown
  • 2013-12-11 EP EP13196736.6A patent/EP2884348A1/de not_active Withdrawn
• 2014
  • 2014-12-05 JP JP2016537496A patent/JP6147437B2/ja active Active
  • 2014-12-05 CN CN201480067082.XA patent/CN105814496B/zh active Active
  • 2014-12-05 US US15/102,104 patent/US10012955B2/en active Active
  • 2014-12-05 WO PCT/EP2014/076783 patent/WO2015086472A2/fr not_active Ceased
  • 2014-12-05 EP EP14811820.1A patent/EP3080666B1/de active Active

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