Crown shaft of a tight wristwatch case, and this enclosing wristwatch case

Description

TECHNICAL FIELD

[0001] The present invention relates to a control element, such as a crown stem of a waterproof watch case, particularly for a diving watch.

[0002] The invention also relates to a watch case comprising a control organ, such as a crown stem for setting time parameters or other functions for a diving watch. TECHNOLOGICAL BACKGROUND

[0003] To ensure the underwater use of a mechanical or electronic watch, the watch case, which houses a timekeeping movement or module, must be completely watertight. This is achieved by having a case back securely attached to one side of the case middle and a crystal attached to the opposite side. Sealing gaskets are used to assemble the case back, case middle, and crystal. A control or adjustment mechanism for the watch's functions is also mounted securely through the case middle when the watch is not in use.

[0004] Watch cases, including those with a control or adjustment mechanism, are generally not designed or assembled to withstand high water pressures, such as those encountered during diving, because the pressure inside the watch case is close to atmospheric pressure. Simple gaskets used on traditional watches are insufficient to guarantee a watertight seal for the case during dives to great depths.

[0005] Patent application CH 690 870 A5 describes a waterproof watch case. The watch case consists of a crystal fixed on its upper side to a case-bezel and a case back fixed to the case by screwing it into an internal threaded hole in the case. The crystal is secured to the case by a toroidal, annular sealing gasket resting against an edge of the case. A sealing gasket is also provided between an outer edge of the case back and a lower surface of the case. Since the threaded hole can be damaged under high water pressure, a resistant metal cup is also provided, resting against an inner surface of the case back and against an inner edge of the case. However, even with this watch case design, it does not guarantee a good seal during dives to very great depths underwater, which is a drawback.

[0006] Swiss patent CH 372 606 describes a waterproof watch case with a central case body surrounding a case back and closed by a crystal. A threaded ring rests against an inclined outer surface of the case back to retain it and is screwed into a mounting part connected to the case body. This arrangement, however, does not guarantee a watertight seal for the case during dives to great depths, which is a drawback.

[0007] Patent application EP 3 432 084 A1 describes a control device, such as a crown stem, mounted through the case of a watch. The crown stem includes a threaded portion for screwing into a tapped hole in a through-hole of the case. An upper portion of the stem, larger in diameter than its threaded portion, rests in its resting position against a wedge in the bottom of a housing for the upper part of the stem. A toroidal sealing gasket is disposed in an annular groove in the upper part of the stem and in contact with the inner wall of the housing to ensure water resistance. However, this arrangement does not guarantee a good seal between the case and its control device during dives to very great depths underwater, which is a drawback.

[0008] Utility model DE 16 15 029 U and patent application CH 291565 A describe a stem-crown for a water-resistant watch case for a diving watch. The stem-crown comprises a stem inserted into a tubular opening in the case middle, and a crown, which includes a first portion connected to the stem internally and a second manipulator portion externally. The first portion includes an annular contact surface inclined at an angle less than 90° to a longitudinal central axis of the stem-crown to contact an annular receiving surface of the case middle of complementary shape.

[0009] Patent application GB 309 485 A describes a crown stem, which includes a first portion for coming into contact with an external surface of the watch case, and a second portion for manipulating the crown stem.

[0010] French patent application FR 1 491 824 A describes a crown that can be screwed onto a fixed part of a watch case for a waterproof diving watch. SUMMARY OF THE INVENTION

[0011] The main purpose of the invention is therefore to overcome the disadvantages of the prior art described above by proposing on the one hand a control element, such as a crown stem of a water-resistant watch case, and on the other hand a water-resistant watch case adapted to withstand the high water pressure for diving to great depths underwater.

[0012] For this purpose, the present invention relates to a control element, such as a crown stem of a water-resistant watch case, which comprises the features of independent claim 1.

[0013] Specific embodiments of the control element are defined in dependent claims 2 to 6.

[0014] One advantage of the control mechanism of a water-resistant watch case lies in its stem-crown design, the crown of which comprises a first portion and a second manipulator portion. The first portion has an annular contact surface inclined at a defined angle less than 90° to a longitudinal central axis of the stem-crown so that it can contact a corresponding annular receiving surface on the case, which has a complementary shape. In this way, once the stem-crown is mounted on the watch case, any difference in water pressure compared to the pressure inside the watch case tends to close any gaps between the inwardly inclined contact surfaces.

[0015] To that end, the present invention also relates to a water-resistant watch case with at least one control element, such as a crown stem, which includes the features of independent claim 7.

[0016] Forms of embodiment of the water-resistant watch case are defined in dependent claims 8 to 11.

[0017] Advantageously, the crown has an annular contact surface, which is inclined at a defined angle less than 90° with respect to a longitudinal central axis of the stem-crown to come into contact with an annular receiving surface of the case, which is of complementary shape in a rest position. BRIEF DESCRIPTION OF THE FIGURES

[0018] The purposes, advantages, and characteristics of the control mechanism, such as a crown stem of a water-resistant watch case, and the watch case itself, will be more clearly shown in the following non-exhaustive description, with reference to the drawings in which: there figure 1 represents, in a simplified manner, a cross-section of a water-resistant case of a diving watch according to the invention, the figures 2a And 2b represent on the one hand a detailed cross-section of the watertight box at the level of the control element in the rest position according to the invention, and on the other hand a detailed cross-section of the watertight box at the level of the control element in the adjustment position according to the invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] In the following description, all the components of a waterproof watch case, particularly a diving watch, which are well known to a person in the trade in this technical field, are only related in a simplified way.

[0020] There figure 1 represents a watch case 1, which can be used for a diving watch. The watch case 1 essentially comprises a crystal 3, which may be made of sapphire or mineral glass, fixed to one upper side of a case middle 2, optionally a case back 4 mounted on one lower side of the case middle 2, and at least one control organ 9, such as a crown stem as shown. The control organ 9 may be mounted watertight in its resting position on or through the case middle 2 or in its setting position as explained in more detail below with reference to figures 2a And 2bThis control element 9 can be used to set the time, date, or other functions for a dive watch. A bezel 7 can also be mounted on the upper side of the case 2. A movement or watch module 10 is housed in the watch case 1 within a casing ring 8.

[0021] The control organ 9 is presented as a stem-crown 9. It mainly comprises a stem 11 and a crown 13 capable of being manipulated by a user's hand outside the watch case 1. In the rest position as shown in the figure 1 The stem 11 passes through a tubular opening 12 in the case 2. This stem 11 is extended by another internal stem to provide access to the interior of the watch case 1 for adjusting time settings or other functions of a dive watch. According to the invention as defined in the accompanying drawing, the stem 11 is held by a retaining means 23 in the tubular opening 12 of the case 2 or at its opening in the watch case. Preferably, the stem 11 is held in a rest position without adjustment. Preferably, the stem 11 includes, at one end facing the interior of the watch case 1, a threaded portion 11' for screwing into an internal thread 23, as a retaining means, in the tubular opening 12 of the case 2.The rod 11 further includes an annular groove 18 with a toroidal sealing gasket 17 in contact with the inner surface of the tubular opening 12, which has a diameter slightly larger than the diameter of the rod 11. The annular groove 18 is disposed between the threaded portion 11' and the crown 13, and preferably closer to the threaded portion 11', such that in the adjustment position the sealing gasket 17 remains in contact within the tubular opening 12.

[0022] The crown 13 comprises a first portion directly connecting the stem 11 and a second manipulator portion. The first portion includes an annular contact surface 21, which is inclined at a defined angle less than 90° with respect to a longitudinal central axis of the stem-crown 9, extending from the connection of the stem 11 to the first portion of the crown 13 outwards from the second portion of the crown 13 or the watch case 1. According to the invention as defined in the attached drawing, the first portion of the crown further comprises a second annular groove 29 housing a second toroidal (Butadiene Rubber Nitrile) sealing gasket 19, located near the connection between the first portion and the second manipulator portion of the crown 13.The second annular groove 29 can have a rectangular cross-section for holding the second sealing gasket 19 in the groove in the adjustment position of the stem-crown 9.

[0023] The annular contact surface 21 of the first portion of the crown 13 is inclined at a defined angle to come into contact with an annular receiving surface 22 of the case 2 in its rest position. This annular receiving surface 22 has a shape complementary to the annular contact surface 21 and normally has the same angle of inclination as the annular contact surface 21. In the case where the annular contact surface 21 of the first portion of the crown 13 is conical in shape, just like the annular receiving surface 22 of the case 2, the angle of inclination α of the surfaces 21, 22 can be on the order of 55° ± 10°, but preferably at 55°, or even at 65°.

[0024] It should also be noted that the first and second portions of the crown 13 form a single solid piece, for example in a material such as titanium, as also for example the case 2. The stem 11 can also come from the same material as the crown to form a single piece.

[0025] The case back 4 includes an annular rim 14 with an internal thread for screwing onto a threaded hole 15 on the lower side of the case 2. An annular bearing surface of the case back 4 contacts an annular inner surface of the case 2, the shape of which is complementary to the bearing surface, when the case back 4 is mounted on the case 2. The bearing and inner surfaces are inclined at a predetermined angle with respect to an axis perpendicular to a plane of the watch case 1. In the case of a generally cylindrical case, the bearing and inner surfaces are conical and inclined inwards towards the watch case 1 at a predetermined angle with respect to a central axis of the watch case 1. The lower side of the case 2 further includes an annular groove 16 housing a toroidal sealing gasket 6 (Butadiene Rubber Nitrile) that contacts the bearing surface when the case back 4 is mounted. on the 2nd build.For a case 2 and a case back 4 made of a material such as titanium, the angle can be approximately 60° ± 5° relative to the central axis. This allows for good stress distribution between the case back 4 and the case 2 due to water pressure during deep underwater diving.

[0026] The crystal 3 is attached to the case 2 according to the same principle as the mounting of the case back 4 to the case 2. To this end, the crystal 3 comprises an annular peripheral surface to be fixed by means of a fixing gasket 5 to an annular inner surface on the upper side of the case 2. The annular inner surface is complementary in shape to the annular peripheral surface. The annular peripheral surface 13 of the crystal 3 is inclined at a defined angle less than 90° to an axis perpendicular to a plane of the watch case 1. Preferably, the annular inner surface is inclined generally towards the interior of the watch case 1 at the same angle as the annular peripheral surface to a central axis. If the case 2 is generally cylindrical, the annular inner surface and the annular peripheral surface are conical.The defined angle of inclination of the surfaces can be approximately 43° ± 5° relative to the central axis. This ensures good stress distribution between the crystal 3 and the case 2 due to water pressure during deep underwater diving. The difference in water pressure compared to the pressure inside the watch case 1 tends to close any gaps between the surfaces in contact with the gasket 5, thanks to the inward inclination of the contact surfaces within the watch case 1. This guarantees a good seal and resistance to high pressures.

[0027] The shown fixing seal 5 can be made of amorphous metal or an amorphous metal alloy. The fixing seal 5 is annular in shape for the airtight sealing of the lens 3 onto the frame 2. For a generally cylindrical frame 2, the fixing seal 5 comprises a conical portion surmounted by a cylindrical portion attached to an annular inner wall of the frame 2 and an annular outer wall of the lens 3. The lens 3 is fixed to the frame 2 via the amorphous metal seal following a hot-fixing operation.

[0028] Several types of amorphous metal alloys can be used to fabricate the entire 5, 5' one-piece metal gasket. In most cases, the amorphous metal alloy is primarily composed of zirconium, allowing the gasket to be formed at temperatures exceeding 350°C, i.e., above the alloy's glass transition temperature. Zirconium-based amorphous metal alloys can be composed of Zr (52.5%), Cu (17.6%), Ni (14.9%), Al (10%), and Ti (5%). Other zirconium-based amorphous metal alloys can include Zr (58.5%), Cu (15.6%), Ni (12.8%), Al (10.3%), and Nb (2.8%). The amorphous zirconium-based metallic alloy may also include Zr(44%), Ti(11%), Cu(9.8%), Ni(10.2%) and Be(25%), or finally Zr(58%), Cu(22%), Fe(8%) and Al(12%).Preferably, to facilitate the production of such a joint, the amorphous metal alloy can be primarily composed of platinum (Pt), allowing the joint to be formed at a temperature above 230°C. The platinum-based amorphous metal alloy can comprise Pt (57.5%), Cu (14.7%), Ni (5.3%), and P (22.5%). Alternatively, the one-piece metal joint 5, 5' can be made from an amorphous metal alloy primarily based on palladium (Pd), allowing the joint to be formed at a temperature above 300°C.

[0029] Other examples of amorphous metal alloys can be cited. A titanium-based amorphous metal alloy might include Ti (41.5%), Zr (10%), Cu (35%), Pd (11%), and Sn (2.5%). A palladium-based amorphous metal alloy might include Pd (43%), Cu (27%), Ni (10%), and P (20%), or Pd (77%), Cu (6%), and Si (16.5%), or finally Pd (79%), Cu (6%), Si (10%), and P (5%). A nickel-based amorphous metal alloy might include Ni (53%), Nb (20%), Ti (10%), Zr (8%), Co (6%), and Cu (3%), or Ni (67%), Cr (6%), Fe (4%), Si (7%), C (0.25%), and B (15.75%), or finally Ni (60%), Pd (20%), P (17%), and B (3%). An amorphous iron-based metal alloy may include Fe (45%), Cr (20%), Mo (14%), C (15%), and B (6%), or Fe (56%), Co (7%), Ni (7%), Zr (8%), Nb (2%), and B (20%). An amorphous gold-based metal alloy may include Au (49%), Ag (5%), Pd (2.3%), Cu (26.9%), and Si (16.3%).

[0030] THE figures 2a And 2brepresent in more detail, on the one hand, a cross-section of the watch case at the level of the control organ 9 in its rest position in the case 2 ( figure 2a ), and on the other hand a cross-section of the watch case at the level of the control organ 9 in the adjustment position, partly outside the opening 12 in the case 2 ( figure 2b ). For the sake of simplicity, only the elements related to the control organ 9 and the case 2 will be described, as all the elements of the watch case have already been mentioned above with reference to the figure 1 .

[0031] In this embodiment, the annular contact surface 21 of the first portion of the crown 13 is considered to be conical in shape, as is the annular receiving surface 22 of the case 2, which is complementary in shape to the annular contact surface 21. figure 2a The first portion of the crown 13 is placed in a conical bearing position within the annular receiving surface 22 of the case 2, once the threaded portion 11' of the stem 11 has been screwed into the internal thread 23 of the tubular opening 12 of the case 2. The angle of inclination α of the surfaces 21, 22 can be on the order of 55° ± 10°, and preferably 55°, or even 65°. In this rest position, the second sealing gasket 19 rests against the annular receiving surface 22 of the case 2. Watertightness is maintained by this, but when the diving watch is at great depths underwater, the conical contact arrangement between the crown 13 and the case 2 allows any gap between the contacting surfaces to be hermetically sealed with a better distribution of stress.

[0032] For adjusting time settings or other functions for a dive watch as shown in the figure 2bThe crown 13 is rotated to unscrew portion 11' of the threaded hole 23 in the tubular opening 12, and the crown 13 is pulled outwards from the watch case. Normally, the stem 11 is connected to the inside of the watch case by another internal stem to a component for adjusting time settings or other functions of the dive watch, but only the stem-crown 9 has been explained as part of the watch case.

[0033] IlIt should also be noted that the cross-section of the first portion of the ring 13 can be square, rectangular, or polygonal. This means that the annular contact surface 21 of the ring can be formed by several inclined plane portions joined together to create the annular bearing surface. Under these conditions, the retaining means 23 in the tubular opening 12 can no longer be a threaded hole, but a stop, hook, or other retaining means.

[0034] From the description just given, several variants of the embodiment of the control organ, such as a stem-crown and of the watch case, can be designed by a person skilled in the art without departing from the scope of the invention defined by the claims.

Claims

1. A control organ (9), such as a stem crown (9) on a water-resistant watchcase (1), in particular for a diving watch, the stem crown comprising a stem (11) designed to be inserted into a tubular opening (12) in a middle (2) of the watchcase (1), and a crown (13) comprising a first portion connected to the stem (11) and a second handling portion, the first portion of the crown (13) comprising an annular contact surface (21), which is inclined at a defined angle of less than 90° relative to a longitudinal central axis of the stem crown (9), extending from the link between the stem (11) to the first portion of the crown (13) towards the outside of the second portion of the crown (13), the first portion of the crown being configured such that it can come into contact with an annular receiving surface (22) of the middle (2) with a complementary shape, and the stem (11) being held by a maintaining means (23) in the tubular opening (12) in the middle (2) or at the entry thereof in the watchcase (1), characterised in that a second annular groove (29) is made in the first portion of the crown (13) closer to the second portion of the crown (13) than to the stem (11), the second annular groove (29) receiving a second toroidal packing (19).

2. The control organ (9) according to claim 1, characterised in that the annular contact surface (21) is a conical surface.

3. The control organ (9) according to any of the preceding claims, characterised in that the angle of inclination of the annular contact surface (21) is on the order of 55° ± 10°.

4. The control organ (9) according to claim 3, characterised in that the angle of inclination of the annular contact surface (21) is 55° or 65°.

5. The control organ (9) according to any of the preceding claims, characterised in that one end of the stem (11) comprises a threaded portion (11') that can be screwed into a tapping (23) as a maintenance means in a tubular opening (12) in a middle (2) of the watchcase (1).

6. The control organ (9) according to claim 5, characterised in that between the threaded portion (11') and the first portion of the crown (13), a first annular groove (18) is made in the stem (11) to receive a first toroidal packing (17).

7. A watchcase (1) comprising at least one control organ (9), such as a stem crown (9) according to any of the preceding claims, the case (1) further comprising at least one back (4) fitted on a lower side of a middle (2), and a glass (3) fitted on an upper side of the middle (2), the middle (2) comprising a tubular opening (12) through which the stem (11) of the stem crown (9) runs and an annular receiving surface (22) of the middle (2) at one end towards the outside of the tubular opening (12) for receiving the first portion of the crown (13) in the lock position, and the annular receiving surface (22) of the middle (2) being of complementary shape to the annular contact surface (21), with a defined angle of inclination of less than 90° relative to a longitudinal central axis of the tubular opening (12) towards the outside of the watchcase (1), the stem (11) being held by a maintaining means (23) in the tubular opening (12) in the middle (2) or at the entry thereof in the watchcase (1), in which, when the stem crown (9) is in the locked position, the tubular opening (12) comprises an internal tapping (23) as a maintaining means into which a threaded portion (11') of the stem (11) is screwed, the annular contact surface (21) bearing against the annular receiving surface (22).

8. The watchcase (1) according to claim 7, characterised in that the annular receiving surface (22) of the middle (2) is conical in shape.

9. The watchcase (1) according to any of claims 7 and 8, characterised in that the angle of inclination of the annular receiving surface (22) is on the order of 55° ± 10° and equivalent to the angle of inclination of the annular contact surface (21).

10. The watchcase (1) according to claim 7, characterised in that a first annular groove (18) is made in the stem (11) for receiving a first toroidal packing (17) in contact with the inner surface of the tubular opening (12).

11. The watchcase (1) according to claim 7, characterised in that a second annular groove (29) is made in the first portion of the crown (13) closer to the second portion of the crown (13) than to the stem (9), the second annular groove (29) receiving a second toroidal packing (19) in contact with the annular receiving surface (22) in the lock position.