CH720432B1 - Device for attaching a watch strap to a watch case with a spring bar - Google Patents

Abstract

The fixing device (100) further includes an elastic return element (12), arranged to return the locking organ (15) so as to reduce the passage opening.

Description

[0001] The present invention relates generally to the field of watchmaking and jewelry, more particularly to the field of devices for attaching bracelets to watch cases having a bar.

[0002] Interchangeable systems for attaching bracelets to watch cases are known. For example, document CH715870 discloses a lock configured to engage with a gripping element, such as a bar, and maintain tension with the latter so as to press an insert against the case middle.

[0003] The prior art system has the disadvantage of being more complicated to implement and of requiring an assembly intervention on the underside of the watch case to manipulate the lock.

[0004] The present invention aims to propose a new construction of a fastening device, facilitating the manufacture and installation on the watch case, while being intuitive to use, more robust and more comfortable for the wearer of the watch.

[0005] The invention relates, in a first aspect, to a device for attaching a bracelet to a watch case having a bar, the attachment device comprising:

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a bracelet terminal link comprising a bar housing formed in the bracelet terminal link and arranged to receive the bar, the housing comprising a beak, such as a projection, boss or protrusion, so as to form a baffle;

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a locking device arranged to define, with the nozzle, a passage opening to the bar housing, and movable, preferably rotationally, between:

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an open position in which the passage opening has a passage width greater than a section of the bar, so as to allow insertion or extraction of the bar from the housing, and

- a blocking position in which the passage opening has a passage width smaller than the cross-section of the bar, so as to block the extraction of the bar;

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an elastic return element, arranged to return the locking device so as to reduce the passage opening.

[0006] This facilitates the manufacture and installation of the fastening device on the watch case, while also being more intuitive to use, more robust, and more comfortable for the watch wearer. Preferably, the user simply has to position the end link of the bracelet above the bar and press down on the end link to lock the device onto the bar.

[0007] Preferably, the bar is pressed into the housing by the locking member.

[0008] This ensures efficient locking of the bar in the housing.

[0009] Advantageously, in the locking position, the locking organ has a protruding counter-form opposite the beak.

[0010] This ensures that the passage opening has a passage width that is smaller than the cross-section of the strip, and thus prevents the strip from coming out of the housing.

[0011] Advantageously, in the open position, the locking member has a hollow counter-form opposite the beak.

[0012] This makes it easier to insert the bar into the housing, in particular when the user presents the terminal link above or opposite the bar.

[0013] Advantageously, the fastening device further includes a first portion of stop, arranged to butt against the box, on the side of a bottom of the box.

[0014] This allows the terminal link to be locked onto the watch case, while cooperating with the locking member, and in particular in the case of an extraction torque in a first direction.

[0015] Advantageously, the fastening device further includes a second stop portion, arranged to butt against the box at the level of a lateral surface (of the box).

[0016] This allows the terminal link to be locked onto the watch case, while cooperating with the locking member and with the first portion of the stop, and in particular in the case of an extraction torque in a second direction, opposite to the first direction.

[0017] According to the invention, the fastening device further comprises an elastic return element, arranged to return the locking member so as to reduce the passage opening.

[0018] Advantageously, the fastening device further includes an elastic return element, arranged to return the locking member towards or against the bar.

[0019] This ensures that the locking element presses the bar or is pulled back towards it.

[0020] Advantageously, the locking member includes a lever portion, arranged to pivot the locking member between the locking position and the open position, or from the open position to the locking position.

[0021] This makes it possible to propose a means of gripping so that the user can act on the locking member, for example for disassembly purposes.

[0022] Advantageously, the fastening device further includes a ball arranged to be pressed against the bar by a ball spring, when the locking member is in the locking position.

[0023] This allows for an additional means of fixing the bar, the ball also being called a locking ball.

[0024] Advantageously, the fastening device further includes a damping portion, preferably made of elastomer, and arranged to absorb or compensate for residual assembly play between the bracelet and the case.

[0025] Preferably, the ball is arranged to be between the bar and the damping portion.

[0026] Advantageously, the fastening device further includes a locking member arranged to lock the locking member in the locking position.

[0027] Advantageously, the locking member is arranged to lock the blocking member in the open position.

[0028] Advantageously, the locking member is arranged to switch between the open position and the locking position.

[0029] A second aspect of the invention relates to a timepiece comprising a fastening device according to the first aspect.

[0030] This makes it possible to offer a timepiece with the advantages mentioned above.

[0031] Other features and advantages of the present invention will become more apparent upon reading the following detailed description, of embodiments of the invention given by way of non-limiting example and illustrated by the accompanying drawings, in which:

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Figure 1 represents a bracelet fastening device according to the present invention, in a position in which the device is detached from a bar of a watch case,

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Figure 2 represents the device in an initial position of insertion of the strip into a slot in the device.

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Figure 3 represents the device in the final stage of inserting the bar into the housing.

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Figure 4 shows the device in a locked position.

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Figure 5 shows the device in another cross-sectional view, at the level of a locking ball.

[0032] Figure 1 represents a fastening device 100 for a bracelet 20 according to the present invention, in a position in which the device 100 is detached from a bar 6 of a watch case 1.

[0033] The watch case 1 includes, in a known manner, a case back 4, a crystal 3 opposite the case back 4, a case middle 2, lugs 7 and two bars 6 between the lugs 7. The watch case 1 is arranged to house a movement 5. Only a portion of the case 1 is shown here, with the device 100 on the right side of Figure 1, but it is of course possible to have a bar 6 and the fixing device 100 on the left side of Figure 1 (not shown).

[0034] The fastening device 100 includes a bracelet end link 22 which is intended to be attached to a bracelet 20 having links 21 successively attached.

[0035] The terminal link 22 includes a bar housing 19 formed in the terminal link. The bar housing 19 is arranged to receive the bar 6. The bar 6 includes a circular cross-section pin and the bar housing 19 is a housing with a circular portion, arranged to receive the bar 6. The bar 6 may be a spring bar, a screwed pin, a pressed pin, a notched pin and tube, a pin machined into the case (one piece with the lugs), it is in any case integral with the case 1.

[0036] The housing 19 further includes a beak 18 at one end thereof, on the side allowing the insertion of the bar 6 into the housing 19.

[0037] The beak 18 is thus a projection, a boss or an outgrowth. The beak 18 is arranged on the outside of the housing 19. The beak 18 thus forms a baffle.

[0038] The device 100 further includes a locking member 15. The locking member 15 is arranged to define with the beak a passage opening to the housing of the bar 19.

[0039] The locking member 15 is movable, preferably rotationally. It can switch between an open position, in which it allows the bar 6 to pass towards the housing 19 to permit the insertion of the bar 6 into the housing 19, and a locking position, in which it prevents the bar 6 from being extracted from the housing 19. It is noted that in the open position, the locking member 15 also allows the bar 6 to pass out of the housing, if it is already inserted, so as to permit its extraction from the housing 19.

[0040] In the open position, the passage opening is wider than the section of the bar 6, and in the locked position, the passage opening is less wide than the section of the bar 6.

[0041] The locking member 15 can switch between the open position and the locking position, by pivoting around an axis 14 provided for this purpose.

[0042] The device 100 further includes an elastic return element 12 (such as a spiral spring, a helical spring, or a leaf spring), arranged to return or angle the locking member 15 towards the bar 6, so as to close the passage opening. The elastic return element 12 can also press the locking member 15 against the bar 6 when the latter is in the housing 19.

[0043] The locking member 15 comprises a protruding counter-form 15p, arranged opposite the nozzle 18 in the locked position, and a recessed counter-form 15c, opposite the nozzle 18 in the open position. In other words, the locking member 15 includes a cam track, and the bar 6 can travel along the cam track during the insertion of the bar 6 into the housing 19.

[0044] The terminal link 22 further includes a first cover piece 11 for concealing the elastic return element 12 and a second cover piece 10 for concealing the housing 19.

[0045] In Figure 1, the device 100 is shown before the bar 6 is inserted into the housing 19. The locking member 15 is in the locking position because it is returned by the elastic return element 12.

[0046] The housing 19, indicated by dotted lines in Figure 1, preferably has a partial circular section in order to receive the bar 6, that is to say, the housing 19 preferably has a counter-form of the shape of the bar 6. The housing 19 can cover an arc of 180 degrees or less.

[0047] The locking member 15 comprises a bearing surface (or contact surface) which is shown in solid line in Figure 1. The bearing surface is arranged to bear against, or be in the immediate vicinity of, the bar 6 when the locking member 15 is in the locked position. The arc formed by the bearing surface of the locking member 15 and the arc of the housing 19 is preferably greater than 180 degrees, so as to block the passage of the bar 6 and prevent its extraction.

[0048] The nozzle 18 can be extended with an insertion surface, in the direction outside the housing and indicated by a bold line in Figure 1. The insertion surface of the nozzle 18 makes it easier to insert the bar 6 into the housing 19.

[0049] Figure 2 represents the fixing device 100 in the initial position of insertion of the bar 6 into the housing 19.

[0050] This initial insertion position corresponds to an open position because the passage opening is larger than the section of the bar 6 and allows the latter to be introduced into the housing 19.

[0051] When the user presses the locking member 15 against the recessed counter-form 15c against the bar 6, the locking member 15 will pivot to open the passage opening and allow the bar 6 to be inserted into the housing 19. The user must apply slight force to overcome the return force of the elastic return element 12. In positioning the recessed counter-form 15c against the bar 6, the user can be guided by a second stop portion 32, for example arranged on the first cover piece 11. In this case, the second stop portion 32 butts against the case 2 (i.e. the lateral surface of the box 1).

[0052] Figure 3 represents the device 100 in the final phase of introducing the bar 6 into the housing 19.

[0053] In the final insertion phase, the bar 6 is at the bottom of the housing 19. The protruding counter-form 15p is then against the bar 6.

[0054] Figure 4 represents the device 100 in the locking position.

[0055] The elastic return element 12 caused the locking member 15 to tilt, so that the protruding counter-form 15p is arranged opposite the beak 18. The passage opening between the locking member 15 and the beak 18 is thus narrower than the cross-section of the bar 6, preventing the bar 6 from being extracted from the housing 19.

[0056] The beak 18 closes the housing 19 in such a way that it forms an obstacle to the extraction of the bar 6 from the housing 19 in cooperation with the locking member 15. In one embodiment, it can be considered as a portion of material (represented between the dotted lines) with respect to a line parallel to the direction of insertion and passing through an end of the housing opposite the locking member 15.

[0057] Figure 5 represents the device 100 in another cross-sectional view, at the level of a locking ball 17.

[0058] The ball 17, also called the locking ball, provides additional locking of the bar 6 in the housing 19. It is housed in a ball cage and supported by a damping portion 16, such as a piece of rubber or elastomer, so as to take up the residual assembly play between the bracelet 20 and the box 1. The ball 17 is pressed against the bar 6 in the locking position.

[0059] The device 100 may further include a locking member in order to lock the locking member 15 in the locking position.

[0060] The device 100 may further include a lever portion to tilt the locking member 15, and allow the user to force the tilting of the locking member 15. The lever portion may, for example, be disposed at one end of the locking member 15, on the side of the hollow counter form 15c.

[0061] The device 100 may further include a first stop portion 31 arranged on the bottom side 4 in order to block a torque applied to the device 100 in cooperation with the locking member 15. The first stop portion 31 allows a torque to be blocked in the clockwise direction in Figure 5 and the second stop portion 32 allows a torque to be blocked in the counterclockwise direction in Figure 5. The end link 22 thus forms an insert, the first stop portion 31 of which is inserted under the box 1.

[0062] It will be understood that various modifications and/or improvements obvious to a person skilled in the art can be made to the different embodiments of the invention described in this description.

[0063] In particular, reference is made to the possibility of having other shapes of bars.

[0064] It is possible to combine embodiments as much as possible or necessary, while remaining within the scope of the annexed claims.

Claims (11)

1. A device for attaching (100) a bracelet (20) to a watch case (1) having a spring bar (6), the attachment device (100) comprising: – a bracelet end link (22) including a spring bar housing (19) formed in the bracelet end link (22) and arranged to receive the spring bar (6), the housing (19) including a beak (18), such as a projection, boss, or protrusion, so as to form a baffle, – a locking member (15) (19) for defining, with the beak (18), a passage opening to the spring bar housing (19), and movable, preferably rotationally, between: – an open position in which the passage opening has a passage width greater than a section of the spring bar (6), so as to allow insertion or extraction of the spring bar (6) from the housing (19), and – a locking position in which the opening of The passage has a narrower width than the cross-section of the bar (6), so as to block the extraction of the bar (6), - an elastic return element (12), arranged to return the locking member (15) so as to reduce the passage opening. 2. Fixing device (100) according to claim 1, wherein, in the locking position, the locking member (15) has a protruding counter-form (15p) opposite the beak (18). 3. Fixing device (100) according to claim 1 or 2, wherein, in the open position, the locking member (15) has a counter-form in hollow (15c), opposite the beak (18). 4. Fixing device (100) according to any one of claims 1 to 3, further comprising a first portion of stop (31), arranged to butt against the box (1), on the side of a bottom of the box (4). 5. Fixing device (100) according to any one of claims 1 to 4, further comprising a second stop portion (32), arranged to butt against the box (1) at the level of a lateral surface of the box (1). 6. Fixing device (100) according to any one of claims 1 to 5, wherein the elastic return element (12) is arranged to return the locking member (15) against the bar (6). 7. A fastening device (100) according to any one of claims 1 to 6, wherein the locking member (15) comprises a lever portion, arranged to pivot the locking member (15) between the locking position and the open position. 8. Fixing device (100) according to any one of claims 1 to 7, further comprising a ball (17) arranged to be pressed against the bar (6) by a ball spring, when the locking member (15) is in the locking position. 9. Fixing device (100) according to claim 8, further comprising a damping portion (16), preferably made of elastomer, arranged to absorb or compensate for residual assembly clearances between the bracelet (20) and the box (1), and in which the ball (17) is arranged to be between the bar (6) and the damping portion (16). 10. Fixing device (100) according to any one of claims 1 to 9, comprising a locking member arranged to lock the locking member (15) in the locked and/or open position. 11. Timepiece comprising a fastening device (100) according to any one of claims 1 to 10 and a watch case (1) having a bar (6) cooperating with the fastening device (100).