Classifications

• • G—PHYSICS
  • G04—HOROLOGY
  • G04D—APPARATUS OR TOOLS SPECIALLY DESIGNED FOR MAKING OR MAINTAINING CLOCKS OR WATCHES
  • G04D3/00—Watchmakers' or watch-repairers' machines or tools for working materials
  • G04D3/0002—Watchmakers' or watch-repairers' machines or tools for working materials for mechanical working other than with a lathe
  • G04D3/0061—Watchmakers' or watch-repairers' machines or tools for working materials for mechanical working other than with a lathe for components for protecting the mechanism against external influences
• • G—PHYSICS
  • G04—HOROLOGY
  • G04D—APPARATUS OR TOOLS SPECIALLY DESIGNED FOR MAKING OR MAINTAINING CLOCKS OR WATCHES
  • G04D3/00—Watchmakers' or watch-repairers' machines or tools for working materials
• • 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
  • G04B37/00—Cases
  • G04B37/04—Mounting the clockwork in the case; Shock absorbing mountings
  • G04B37/05—Fixed mountings for pocket or wrist watches
  • G04B37/055—Fixed mountings for pocket or wrist watches with shock damping means including the winding stem
• • 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
  • G04B37/00—Cases
  • G04B37/08—Hermetic sealing of openings, joints, passages or slits
  • G04B37/081—Complete encasings for wrist or pocket watches also comprising means for hermetic sealing of the winding stem and crown
• • 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
  • G04B37/00—Cases
  • G04B37/22—Materials or processes of manufacturing pocket watch or wrist watch cases
• • 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
  • G04B37/00—Cases
  • G04B37/22—Materials or processes of manufacturing pocket watch or wrist watch cases
  • G04B37/223—Materials or processes of manufacturing pocket watch or wrist watch cases metallic cases coated with a nonmetallic layer

Definitions

• the present invention relates to a method of manufacturing a watch case comprising a middle part, a base and a support ring intended to support internal elements of the watch, in which the middle part and the support ring are manufactured separately, then the support ring is fixed inside the middle by means of an element made of elastomeric material.
• the invention also relates to a watch case which can be obtained by this method.
• the present invention aims to overcome the problems mentioned above, by providing a simple and economical manufacturing process, which allows correct and precise positioning of the movement in the middle of the watch case and compensation for any deviations in dimensions from the middle part, in particular by avoiding machining operations inside the middle part.
• the invention also aims to facilitate the production of the sealing means of the watch case.
• the invention relates to a method of the kind defined in the preamble, characterized in that at least a part of the element of elastomeric material is formed by molding in a gap between the middle part and the support ring, step during which the support ring is held in a desired position inside the middle by means of at least one core which is positioned relative to one or more reference surfaces of the middle.
• the elastomeric nature of the material molded in the gap between the support ring and the middle allows to overcome the constraints, previously very strict, in terms of shape and dimensions of interior machining of the middle.
• the support ring in particular when it is a casing circle, does not need to be positioned by pressing against interior surfaces of the middle part, in particular the surfaces which will be in contact with the elastomer. This allows to choose other places as reference surfaces for its positioning, for example external surfaces of the middle which should in any case be machined or polished, or surfaces which are decisive for the external appearance of the watch, such as the notch ice or bottom.
• the element made of elastomeric material is overmolded in said interval by injection, by transfer or by compression.
• This element can comprise at least a part which is put in place before the overmolding step.
• the element the element made of elastomeric material may constitute a seal between the middle part and the bottom of the case, and / or between the middle part and a control rod passing through the middle part, and / or between the middle part and an ice cream from the box.
• the overmolded elastomeric material is chosen so as to adhere to the material of which the middle part is made.
• FIG. 1 is a view in partial section of part of a watch case manufactured according to a first embodiment
• FIG. 2 is a view similar to FIG. 1, but at another place in the box
• FIG. 3 is a view similar to FIG. 1, showing the complete case and internal elements of the watch
• FIG. 4 is a view similar to FIG. 1, schematically illustrating the step of overmolding by injection of elastomeric material
• FIG. 5 is a view similar to FIG. 3, showing a second embodiment
• Figure 6 schematically illustrates the overmolding step in the second embodiment.
• the watch case 1 shown in FIGS. 1 to 3 comprises a middle part 2, a casing circle 3 and a base 7.
• a movement 4 and a dial 5 will be supported by the casing circle 3.
• An element made of elastomeric material molded 9 fills the entire gap between the circle 3 and the middle part 2 and is extended, in a lateral hole of the middle part, by a tubular part 9 'the interior of which forms a housing 10 intended to receive - 4 -
• FIG. 1 shows a section angularly offset from the section of Figure 1. This is how the orifice 13 of the housing 10 is outside the cutting plane.
• Figure 2 shows the location 6 of the movement 4, as well as the location 8 of the bottom 7.
• the circle 3 has a cavity 14 intended to receive a lug of the movement 4, this lug being intended to make the movement 4 integral with the circle 3.
• FIGS. 1 and 2 show a shoulder 15 of the circle 3, embedded in the elastomer element 9. This shoulder makes the circle 3 and the element 9 integral after overmolding.
• the elastomer element 9, in FIG. 3, provides a seal both between the base 7 and the middle part 2 and between the middle part and the control rod 17, thanks to the bead 12.
• the bottom 7 is fixed by clipping on the lower part of the elastomer element 9, thanks to a notch 16, which ensures a tight assembly.
• the glass 18 is sealed, in the example described, by a gasket 19 separate from the elastomer element 9 and compressed between the edge of the glass and a cylindrical surface 20 of the middle, called a notch of ice.
• a gasket 19 separate from the elastomer element 9 and compressed between the edge of the glass and a cylindrical surface 20 of the middle, called a notch of ice.
• the elastomer element 9 has a shape extending upwards, behind a flange 21 placed above the dial 5 as shown in Figure 5, to form a seal ensuring the seal between glass 18 and middle 2.
• FIG. 4 describes the step of overmolding by injection allowing the elastomer element to be formed 9.
• the surfaces of the middle part 2 and of the casing ring 3 on which the elastomer will be applied are coated beforehand with a primer liquid capable of promoting adhesion of the elastomer.
• the middle part 2 is placed in a mold whose fixed part (not shown) perfectly supports the outside of the middle part, in order to prevent it from bursting under the injection pressure, which can reach very high values.
• the drawer 24 can be - 5 -
• the elements 22 to 24 are movable in the directions indicated by the arrows.
• the elastomer is injected in a known manner through the cores 22 and / or 23, through holes being formed through the circle 3.
• the lateral positioning of the circle 3 relative to the middle part 2 is not done by pressing against the middle, but only by means of the upper core 22, guided by the notch of ice 20 serving as a reference surface on the middle.
• An upper surface 26 of the middle part can serve as a height reference surface, if necessary.
• the casing ring 3 and all the elements which it carries, in particular the movement and the dial, will occupy exactly the desired position in the watch, in particular so as to be perfectly centered at this opening, independently of any inaccuracies of the shape. interior of the middle.
• the same goes for the position of the bottom, which will be defined by the lower part of the element 9, molded by means of the lower core 23 which is guided in a conventional manner by the upper core 22.
• the drawer 24 is withdrawn towards the outside, the lower core 23 is torn down and the upper core 22 is then withdrawn upwards.
• the self-adhesion properties of the elastomeric material 9 allow it to make the circle 3 and the middle part 2 perfectly integral, by removing the constraints of internal shape of this middle part. It is understood that in certain cases, it may be preferable to constitute the element of elastomeric material 9 by assembling various elements, each coming in a portion of the interval between the circle 3, the middle part 2, the housing 10 and possibly the bottom 7.
• the tubular part 9 ′ could be produced beforehand, either by overmolding, or prefabricated and fixed in the hole of the middle before the overmolding step.
• Figures 5 and 6 show a second embodiment of the invention, the differences from which will be described with respect to the first mode.
• the elastomer element 9 is molded between the middle part 2 and a support ring formed here by the flange 21.
• the element 9 also fulfills the function of a casing circle, since its inner surface obtains by molding a precise position and dimensions, regardless of any inaccuracies inside the middle.
• the element 9 has an internal shoulder 30 in which an external thread 31 of the movement takes place.
• the elastomer element 9 extends upward to form, along the notch 20, a seal 32 between the glass 18 and the middle part.
• Figure 6 shows schematically that the elastomer element 9 shown in Figure 5 is molded in a similar manner to what has been described with reference to Figure 4, but in this case the guidance of the cores 22 and 23 is slightly different.
• the upper core 22 is guided laterally on the middle band, that is to say the peripheral surface of the middle part 2, serving as a reference surface 33.
• the lower core 23 is guided relative to the upper core 22 by vertical sliding, for example on shafts 34 passing through the two cores. The vertical positioning can be carried out by pressing on the upper surface 26 of the middle serving as a reference surface.
• the method according to the invention is applicable regardless of the method of manufacturing the middle part and the other parts of the watch case.
• machining inside the middle part is particularly advantageous when it is possible to dispense with machining inside the middle part. This is particularly the case when it is formed by molding, for example according to the MIM (Metal Injection Molding) process or when it is made of ceramic, hard metal or another material capable of being molded.
• MIM Metal Injection Molding

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Injection Moulding Of Plastics Or The Like (AREA)
• Electric Clocks (AREA)
• Gasket Seals (AREA)
• Electromechanical Clocks (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=4187766

Family Applications (2)

Family Applications Before (1)

Country Status (9)

Cited By (1)

Families Citing this family (16)

Family Cites Families (8)

• 1998
  • 1998-02-27 CH CH00471/98A patent/CH693049A5/fr not_active IP Right Cessation
• 1999
  • 1999-02-02 EP EP99102069A patent/EP0939351A1/de not_active Withdrawn
  • 1999-02-26 EP EP99904678A patent/EP0980543B1/de not_active Expired - Lifetime
  • 1999-02-26 WO PCT/CH1999/000092 patent/WO1999044104A1/fr not_active Ceased
  • 1999-02-26 CN CN99800194A patent/CN1122897C/zh not_active Expired - Fee Related
  • 1999-02-26 JP JP54300599A patent/JP4384268B2/ja not_active Expired - Lifetime
  • 1999-02-26 ES ES99904678T patent/ES2234239T3/es not_active Expired - Lifetime
  • 1999-02-26 KR KR1019997009756A patent/KR100613540B1/ko not_active Expired - Fee Related
  • 1999-02-26 DE DE69921914T patent/DE69921914T2/de not_active Expired - Lifetime
  • 1999-02-26 US US09/403,588 patent/US6213635B1/en not_active Expired - Lifetime

Non-Patent Citations (1)

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