SCREW-ON CROWN

Description

Scope of the invention

[0001] The invention relates to a screw-in crown for a watch case comprising a case body with at least one through-hole for receiving said screw-in crown, said screw-in crown comprising a tube arranged to be inserted into said hole in an axial direction around a crown axis, and said screw-in crown being arranged to seal said hole in a watertight manner, said screw-in crown comprising a sub-assembly comprising a crown body manipulable by a user, said sub-assembly being axially movable in said axial direction relative to said tube, and said sub-assembly comprising at least one spring mechanism with at least one spring mounted in compression in a chamber and extending in said axial direction.

[0002] The invention further relates to a watch case comprising at least one housing for receiving a screw-in crown, and a screw-in crown arranged to cooperate with said housing and seal it tightly.

[0003] The invention also relates to a watch comprising such a watch case.

[0004] The invention also relates to a method of mounting such a screw-on crown in a watch case. Background of the invention

[0005] Screw-down crowns are commonly used on watches to improve their water resistance at the point where a control mechanism, such as a winding or regulating stem, passes through. This type of crown has the unique characteristic of being able to assume a screw-down position, in which the watch can be wound, set, adjusted, or otherwise operated, and a screw-down position, in which the crown is screwed and locked onto a tube driven or screwed into the watch case to compress a gasket, thus improving the watch's water resistance. The screw-down position is therefore the normal position when the watch is worn and remains relatively constant, except for wear and tear on the gasket.

[0006] These screw-in crowns contain a spring, against which the screwing action is performed. Most of the time this spring is a helical spring, which bears on an inner surface of the crown, and the friction of the last strand of this spring on this surface causes wear, and therefore contamination of the crown mechanism, or even the watch, by wear particles, which must be avoided.

[0007] Document FR2987684A1, in the name of CHEVAL FRERES, describes an assembly with a screw-down crown and an associated rotating indicator bezel, known as a rehaut, designed to be positioned inside a watch case, between its crystal and the periphery of its dial. The assembly includes a control shaft for operating the rehaut and a broached tube attached to the crown. The control shaft is secured at one end to the broached tube. A fixed tube is designed to be screwed or pressed into a lateral opening in the watch case, with the control shaft passing freely through the fixed tube. A pinion is arranged at the other end of the control shaft, engaging with a toothed peripheral area of ​​the rehaut. This assembly also includes clutching and disengagement means. Initial clutching and disengagement means are interposed between one end of the crown's broached tube and one end of the control shaft.Secondary clutch-disengagement means are interposed between the other end of the same control shaft and the pinion. These first and second means act respectively as clutches and disengagements for a clockwise rotation of the ring gear, and conversely in a counterclockwise rotation, so as to drive the pinion in a unidirectional rotary motion. Summary of the invention

[0008] The invention aims in particular to overcome the drawback linked to the wear caused by the end of the spring, and thus to provide a screwed crown that is more reliable than those known to date.

[0009] Thus, the invention relates to a screwed crown according to claim 1.

[0010] The invention further relates to a watch case comprising at least one housing for receiving a screw-in crown, and a screw-in crown arranged to cooperate with said housing and seal it tightly.

[0011] The invention also relates to a watch comprising such a watch case.

[0012] The invention also relates to a method of mounting such a screw-on crown in a watch case. Brief description of the drawings

[0013] Other features and advantages of the invention will become more apparent upon reading the following description of a particular embodiment of the invention, given by way of simple illustrative and non-limiting example, and the accompanying figures, among which: there figure 1 is a longitudinal cross-sectional view of a screwed crown according to the invention; the figure 2 is a view from below of the inner part of the crown of the figure 1 ; there figure 3 is one of the tops of the crown of the figure 1 ; there figure 4 is a longitudinal cross-sectional diagram representing the crown of the figure 1 mounted on the case of a watch; the figure 5is a block diagram representing a watch with a case equipped with such a crown. Detailed description of preferred embodiments

[0014] The invention relates to a screw-in crown 100 for a watch case 200. This watch case 200 conventionally comprises a case middle 110, with at least one through-hole 90 for receiving the screw-in crown 100.

[0015] This screwed crown 100 has a tube 5, which is arranged to be inserted into the housing 90 in an axial direction around a crown axis D. The screwed crown 100 is arranged to seal the housing 90 in a watertight manner.

[0016] This screw-on crown 100 comprises a subassembly 20, which includes a crown body 1 that can be manipulated by a user. This subassembly 20 is axially movable along the axial direction relative to the tube 5. The subassembly 20 includes at least one spring mechanism, with at least one spring 4 mounted in compression in a chamber 32 and extending along the axial direction D. This spring 4 is, in particular but not limited to, a helical spring.

[0017] According to the invention, the subassembly 20 comprises, bearing on at least one distal end of the spring 4 on a first side, a support washer 9. This support washer 9 has a boss on a second side opposite to the first side, and more particularly this boss is or comprises a spherical cap 99, which is centered on the axis of the crown D. And this spherical cap 99 is arranged to bear on a bearing surface 290 which comprises a constituent of the subassembly 20.

[0018] In a variant which is not part of the invention, the crown body 1 directly comprises the bearing surface 290.

[0019] According to the invention, and as seen on the figure 1 , the component which includes this bearing surface 290 is a cap 2, which is arranged to be fixed to the crown body 1.

[0020] According to the invention, this cap 2 is arranged to cooperate by screwing with the crown body 1 and / or to surround the tube 5 in a sealed connection by axial compression of a sealing gasket 25 in a fully screwed position of the subassembly 20 on the tube 5.

[0021] More specifically, this cap 2 has a cap thread 21, which is arranged to cooperate in a complementary way with a body thread 11, which is included in the crown body 1.

[0022] More particularly, the cap 2 surrounds the tube 5, and it includes a groove or a housing 24, for receiving at least one first sealing gasket 25, which is arranged to bear against a bearing surface 57 that comprises the tube 5. The tube 5 also advantageously includes a gasket bearing surface 56, in particular inclined with respect to the axis of the crown D, and which is arranged to compress at least axially the first sealing gasket 25 in a fully screwed position of the subassembly 20 on the tube 5.

[0023] More specifically, this cap 2 has a circlip groove 23, which is arranged to receive a cap circlip 26 for the axial stop of the first sealing gasket 25, along the axial direction D.

[0024] In the particular variant illustrated by the figures, and in no way limiting, since the invention is applicable to many models of screwed crowns, the subassembly 20 comprises, directly or indirectly attached to the crown body 1, a fixed barrel 3 which extends along the axial direction D, and which comprises a first thread 31, which is arranged to cooperate with a first tapping 51, which comprises the tube 5, for screwing the subassembly 20 onto the tube 5.

[0025] And this subassembly 20 includes a movable barrel 7, which includes fastening means 71, which are arranged for fixing the screwed crown 100 to a control member housed in a box 200. This movable barrel 7 is axially movable along the axial direction D against the spring 4 in the chamber 32, which is defined on the one hand by the fixed barrel 3 and on the other hand by the crown body 1 or by a cap 2 integral with the crown body 1. The movable barrel 7 is captive mounted in this chamber 32.

[0026] More specifically, sub-assembly 20 is non-removable.

[0027] In particular, the crown 2 is fixed in a non-removable manner to the crown body 1, for example by bonding with a two-component resin, or similar.

[0028] More specifically, the fixed barrel 3 is fixed in a non-removable way to the cap 2, for example by laser welding, or other means.

[0029] More specifically, the subassembly 20 includes the crown body 1 surrounding the cap 2, which carries the fixed barrel 3 with which it defines the chamber 32 in which are mounted captive the support washer 9 in support by its spherical cap 99 with the bearing surface 290, which comprises the cap 2, the spring 4, and the movable barrel 7.

[0030] More specifically, the cap 2 includes a trunnion 29 which guides a bore 39 which includes the fixed barrel 3. More specifically, this trunnion 29 includes the bearing surface 290, which extends substantially perpendicularly to the axis of the crown D.

[0031] More specifically, the tube 5 has at least one sealing groove 54 for receiving at least one second sealing gasket 55, which is arranged to cooperate with a housing 90 of a box 100.

[0032] More specifically, the tube 5 has an end machining 52, which is arranged to cooperate with axial locking means 53 for the axial locking of the screwed crown 100 when it is in the service position in a housing 90. In one embodiment, this end machining 52 is a circlip groove arranged to cooperate with a locking circlip constituting the axial locking means 53. In another embodiment, the end machining 52 is a thread, or respectively a tapped hole, arranged to cooperate with a tapped hole, or respectively a thread, that comprises a nut constituting the axial locking means 53.

[0033] More specifically, the tube 5 has a shoulder 59, the projection of which onto a plane perpendicular to the crown axis D is not of revolution, and which is arranged to cooperate with a shaped housing in a case 110. figure 2shows such a four-sided shoulder 59, arranged to cooperate with a square recess in the case. Thus, it is not necessary for the tube 5 to be screwed or driven into the recess 90 of the case 110; it is then held angularly by this shoulder 59, and axially by the axial locking means 53. Naturally, a conventional mounting, driven and / or screwed, along the axial direction D, of the tube 5 in the recess 90 of the case 110 is also possible.

[0034] More specifically, as seen on the figure 3, the screwed crown 100 is a screwed crown which has a pattern on an end face of the crown body 1 or in its vicinity, and this pattern 19 is arranged to take, in the fully screwed position of the subassembly 20 on the tube 5, as many indexed positions as the cooperation of the shoulder 59 with a housing of complementary shape that the case 110 has, here four positions in the embodiment illustrated by the figures.

[0035] In yet another variant, the screwed crown 100 is an orientable screwed crown.

[0036] The invention further relates to a watch case 200, comprising at least one such screwed crown 100, and comprising a case 110 with at least one through-hole 90 for receiving such a screwed crown 100.

[0037] More specifically, this box 200 has a shaped housing which is not of revolution, and has a screwed crown 100 with a shoulder 59, which is arranged to cooperate with this shaped housing, in at least one indexing position.

[0038] The invention also relates to a timepiece, in particular a watch 1000, comprising such a case 200.

[0039] The invention further relates to a method of mounting such a screw-in crown 100 in a watch case, comprising the following steps: prepare the subassembly 20, by inserting the support washer 9 in support of the spring 4 in the chamber 32, and in support, by its spherical cap 99, on a bearing surface 290 which comprises a constituent of the subassembly 20; fix the fixed barrel 3 to the crown body 1 or to a component fixed to the crown body 1 in a non-removable manner; screw the tube 5 to the fixed barrel 3 by enclosing at least one first sealing gasket 25 between the tube 5 and the subassembly 20; prepare the tube 5 for its fixing in a housing 90, and equip it with at least one second sealing gasket 55.

[0040] More specifically, during the preparation of subassembly 20, the fixed barrel 3 is irreversibly fixed to the cap 2, which is irreversibly fixed to the crown body 1.

[0041] In particular, the screwed crown 100 is assembled, and the tube 5 is inserted axially along the axial direction D into the housing 90 of the case 110, it is fixed to the case 110 by screwing or driving until a screwing stop position or respectively driving position.

[0042] More specifically, when inserting the tube 5 into the housing 90, the shoulder 59, if the tube 5 has one, is aligned with the complementary shaped housing of the case 110, in a desired indexing position.

Claims

1. A screw-down crown (100) for a watchcase (200) comprising a middle (110) with at least one through-bed (90) for holding said screw-down crown (100), said screw-down crown (100) comprising a tube (5) designed to be inserted into said bed (90) in an axial direction around a crown axis (D), and said screw-down crown (100) being arranged so as to sealingly close said bed (90), said screw-down crown (100) comprising a subassembly (20), comprising a crown body (1) that can be handled by a user, said subassembly (20) being axially mobile in said axial direction relative to said tube (5), and said subassembly (20) comprising at least one spring-loaded mechanism with at least one spring (4) mounted such that it is compressed inside a chamber (32) and extending in said axial direction (D), the screw-down crown being characterised in that said subassembly (20) comprises, bearing on at least one distal end of said spring (4) on a first side, a support washer (9) comprising, on a second side opposite said first side, a spherical calotte (99) centred on said crown axis (D), said spherical calotte (99) being arranged so as to bear on a bearing surface (290) comprised in a constituent part of said subassembly, said constituent part comprising said bearing surface (290) being a cap (2) arranged so as to be fastened to said crown body (1), said cap (2) comprising a cap threading (21) designed to engage with a body tapping (11) comprised in said crown body (1).

2. The screw-down crown (100) according to claim 1, characterised in that said cap (2) surrounds said tube (5), and comprises a groove or a bed (24) for holding at least one first gasket (25) arranged so as to bear on a shoulder (57) comprised in said tube (5), which further comprises a gasket-bearing surface (56) arranged so as to at least axially compress said first gasket (25) in a position in which said subassembly (20) is fully screwed down onto said tube (5).

3. The screw-down crown (100) according to any of claims 1 or 2, characterised in that said cap (2) comprises a circlip groove (23) arranged so as to hold a cap circlip (26) for axially stopping, in said axial direction, a first gasket (25).

4. The screw-down crown (100) according to any of claims 1 to 3, characterised in that said subassembly (20) comprises, directly or indirectly attached to said crown body (1), a fixed pipe (3) which extends in said axial direction and which comprises a first threading (31) designed to engage with a first tapping (51) comprised in said tube (5) for screwing said subassembly (20) onto said tube (5), and in that said first subassembly (20) comprises a mobile pipe (7) comprising fastening means (71) arranged so as to fasten said screw-down crown (100) to a control member turned in a said case (200), said mobile pipe (7) being capable of moving axially in said axial direction against said spring (4) in said chamber (32) formed, on one hand, by said fixed pipe (3) and on the other hand by said crown body (1) or by a cap (2) attached to said crown body (1), and in which chamber (32) said mobile pipe (7) is immovably mounted.

5. The screw-down crown (100) according to claim 4, characterised in that said subassembly (20) is undetachable.

6. The screw-down crown (100) according to any of claims 1 to 5, characterised in that said cap (2) is undetachably fastened to said crown body (1).

7. The screw-down crown (100) according to claim 4 and any of claims 1 to 6, characterised in that said fixed pipe (3) is undetachably fastened to said cap (2).

8. The screw-down crown (100) according to claim 4 and any of claims 1 to 7, characterised in that said subassembly (20) comprises said crown body (1) surrounding said cap (2), which carries said fixed pipe (3) with which it forms said chamber (32) in which said support washer (9) bearing via its said spherical calotte (99) on said bearing surface (290), comprised in said cap (2), said spring (4), and said mobile pipe (7) are immovably mounted.

9. The screw-down crown (100) according to claim 4 and any of claims 1 to 8, characterised in that said cap (2) comprises a trunnion (29) which guides a bore (39) comprised in said fixed pipe (3).

10. The screw-down crown (100) according to claim 9, characterised in that said trunnion (29) comprises said bearing surface (290) extending substantially perpendicular to said crown axis (D).

11. The screw-down crown (100) according to any of claims 1 to 10, characterised in that said tube (5) comprises at least one gasket groove (54) for holding at least one second gasket (55) arranged so as to engage with a bed (90) in a said case (100).

12. The screw-down crown (100) according to any of claims 1 to 11, characterised in that said tube (5) comprises an end machining (52) arranged so as to engage with axial stop means (53) for axially stopping said screw-down crown (100) when it is in the service position in a said bed (90).

13. The screw-down crown (100) according to claim 12, characterised in that said end machining (52) is a circlip groove arranged so as to engage with a stop circlip forming said axial stop means (53).

14. The screw-down crown (100) according to claim 12, characterised in that said end machining (52) is a threading, or respectively a tapping, arranged so as to engage with a tapping, or respectively with a threading, comprised in a nut forming said axial stop means (53).

15. The screw-down crown (100) according to any of claims 1 to 14, characterised in that said tube (5) comprises a shoulder (59), the projection of which on a plane perpendicular to said crown axis (D) is non-rotational and which is arranged so as to engage with a shaped bed comprised in a said middle (110).

16. The screw-down crown (100) according to claim 15, characterised in that said screw-down crown (100) is a screw-down crown comprising a pattern (19) on an end face (18) of said crown body (1) or in the vicinity thereof, said pattern (19) being arranged so as to take, in a position in which said subassembly (20) is fully screwed onto said tube (5), as many indexed positions as allowed by the engagement of said shoulder (59) with a said shaped bed comprised in a said middle (110).

17. The screw-down crown (100) according to any of claims 1 to 14, characterised in that said tube (5) is arranged so as to be screwed or driven into said bed (90) in said axial direction.

18. The screw-down crown (100) according to any of claims 1 to 17, characterised in that said screw-down crown (100) is an orientable screw-down crown.

19. A watchcase (200) comprising at least one screw-down crown (100) according to any of claims 1 to 18, and comprising a middle (110) with at least one through-bed (90) for holding a said screw-down crown (100).

20. The case (200) according to claim 19, comprising a non-rotational shaped bed and comprising a screw-down crown (100) according to claim 15 or 16, in which said shoulder (59) is arranged so as to engage with said shaped bed, in at least one indexing position.

21. A watch (1000) comprising a case (200) according to claim 19 or 20.

22. A method for mounting a screw-down crown (100), according to claim 4 and according to any of claims 1 to 18, in a bed (90) in a watchcase, comprising the following steps: - preparing said subassembly (20) by inserting said support washer (9) bearing on said spring (4) inside said chamber (32), and bearing, via its spherical calotte (99), on a said bearing surface (290) comprised in a constituent part of said subassembly (20); - undetachably fastening said fixed pipe (3) to said crown body (1) or to a component undetachably fastened to said crown body (1); - screwing said tube (5) to said fixed pipe (3), enclosing at least one first gasket (25) between said tube (5) and said subassembly (20); - preparing said tube (5) to be fastened inside a said bed (90) and equipping the tube with at least one second gasket (55).

23. The method for mounting a screw-down crown (100) according to claim 22, characterised in that, when preparing said subassembly (20), said fixed pipe (3) is immovably fastened to said cap (2), which is immovably fastened to said crown body (1).

24. A method for mounting a case (100) according to claim 22 or 23, characterised in that said screw-down crown (100) is mounted according to claim 22 or 23 and in that said tube (5) is axially inserted in said axial direction inside said bed (90) in said middle (110), in that it is screwed or driven into said middle (110) up to a screw-down stop position or respectively to a drive stop position.

25. The method according to claim 24 for assembling a case (100) according to claim 19, when it depends from claim 15, characterised in that, when inserting said tube (5) into said bed (90), said shoulder (59) is aligned with said shaped bed, in a desired indexing position.