GB2114643A - Bracelet and watch case assembly - Google Patents

Abstract

An integral recessed tab 2 on the watch case 1 is received by an aperture 11 defined by a bridging member 9 attached to the end of a bracelet 5. The bridging member has an integral deflectable detent 9b which is deflected upon insertion of the tab before engaging the recess to secure the bracelet to the watch case. The detent is struck from a plate portion of the bridging member and has a V-shaped cross-section. A flexing axis of the detent is strengthened by means of a C-shaped pressing. <IMAGE>

Description

SPECIFICATION Bracelet and watch case assembly This invention relates to a bracelet and watch case assembly and more particularly to fastening means for fastening at least one end of the bracelet to the watch case.

Typical known means for fastening the end of a bracelet to a watch case include either a bar having a resilient end portion or portions, or a rigid bar. In the case of using a resilient bar, the watch case may have a pair of spaced lugs with respective apertures for receiving each end portion of the bar. The bar is usually received in a sleeve attached to the end of the bracelet and the bar includes spring means which enable one or both of its end portions to be depressed, so as to reduce the bar length, thereby enabling the bar to be fitted to lugs of the watch case. In the case of using a rigid bar, this usually acts as a hinge pin which passes through aligned apertures in the last link of the bracelet and also in a lug or lugs on the watch case. The rigid bar is secured, for example, by peening its ends.Both of these known techniques are time consurning and do not result in a smooth junction between the ends of the bracelet and the watch case, i.e. to give a onepiece effect. Moreover, the use of a resilient bar involves additional precision engineering. Hence, these known techniques can lead to increased manufacturing costs besides detracting from a desirable one-piece effect of a bracelet and watch case.

The present invention seeks to provide fastening means having a simple construction, which can be employed to facilitate attachment of the end or ends of a bracelet to a watch case, and which can be employed to give a one-piece effect.

More particularly, the invention provides a bracelet and watch case assembly wherein the watch case has an integral tab provided with a recess, and wherein at least one end of the bracelet has a bridging member which defines an aperture for receiving said tab, said bridging member including a detent which is resiliently deflectable, upon insertion of said tab in said aperture, and which thereafter engages the recess in said tab to secure said one end of the bracelet to the watch case.

Preferably, the detent is an integral part of the bridging member, for example, it is struck from a plate portion of the bridging member and is mainly deflectable with respect to a flexing axis. In one embodiment, the flexing axis is strengthened by a pressing, suitably in the form of a generally C-shaped ridge. The detent may have a folded form with a substantially V-shaped cross-section, one of the limbs of the V-shape extending freely in a direction away from the end of the bracelet and inclined towards the inner side of the bracelet. The free limb may terminate in an edge, e.g. a sharpened edge, for engaging the corresponding corner of the recess in the integral tab. This corner engaging edge may have a central cut away portion or notch to assist in parting the integral tab from the bridging member, i.e. in order to separate the watch case from the end of the bracelet.In one embodiment, the recess is preferably substantially V-shaped. In any event, on assembly the recess would normally be aligned in the direction transverse of the inner side of the bracelet. Usually, it is not necessary to separate the end of the bracelet from the watch case, but if this is required, then a tool (such as the blade of a watch makers screw driver, or a metal rod, or the like) can be inserted in the cut away portion or notch so as to lever the detent out of securing engagement with the recess in the integral tab.

Thus, although such forceable release of the detent is possible, the detent would be rigid enough to ensure semi-permanent attachment of the bracelet to the watch case.

The end of the bracelet may define a channel for receiving the integral tab, and the tab may have a stepped profile to engage with a corresponding profile on the end of the bracelet, i.e. in the region of the bridging member, whereby a rigid engagement is provided. A flared end portion may be incorporated in the end of the bracelet to provide a smooth transition with the sides of the watch case. In another alternative arrangement, a one piece effect is achieved by providing a bevel on the watch case at the same angle to the front of the watch case as the tab, and setting the tab back from the front of the watch case by a distance corresponding to the strap thickness, so that the upper face of the strap provides a continuation of the plane of the bevel.

Embodiments of the invention will now be described with reference to the accompanying schematic drawings, in which: Fig. 1 is a perspective view of a first embodiment illustrating part of a watch case provided with a tab for insertion into an aperture defined by a bridging member secured to one end of a bracelet, Fig. 2 is a side elevation of the watch case and the end of the bracelet of Fig. 1, prior to fastening, Fig. 3 is an elevation, similar to Fig. 2, but showing the bracelet fastened to the watch case, Fig. 4 is a plan view of the end of the bracelet of Fig. 1, Fig. 5 is a perspective view similar to Fig. 1 of a further embodiment of the present invention, Fig. 6 is a side elevation of the watch case and the end of the bracelet of Fig. 5, prior to fastening, Fig. 7 is an elevation, similar to Fig. 6, but showing the bracelet fastened to the watch case, and Fig. 8 is a plan view of the end of the bracelet of Fig. 5.

Referring to the drawings, a watch case 1 has an integral tab 2 which is provided with a recess 3.

Fig. 1 shows the underside of the watch case whereby the recess 3 faces inwardly, i.e. towards the wrist of the wearer. The tab 2 is of planar construction and the recess 3, which is provided in its major surface, has an undercut or inclined side wall 4 adjacent the leading end of the tab. This leading end has a thinner section relative to the thicker section adjacent the watch case 1 (as best seen in the cross-sectional views of Figs. 2 and 3).

This thickened section has a stepped profile with step faces 2a, 2b (referred to below).

The bracelet 5, as illustrated, is of a type comprising an outer elongate metal cover 5a having a sequence of parallel slits giving the appearance of links, the cover 5a being secured to an elongate perforate metal inner member 5b by means of two rows of turned-down ears 5d, i.e.

along the side edges of the bracelet. A base-plate portion Sc is secured to the inner member 5b (Fig. 3), part of this baseplate portion being seen in Fig. 1. Portion Sc has a cut-out for accommodating part of the thickened section of the integral tab 2 (i.e. having the stepped profile), whereby the tab is supported laterally.

The bracelet 5 also has a metal end portion 6 which is smoothly continuous with, and similar in appearance to the metal cover 5a and which is flared, as shown in Figs. 1 and 4, to provide a smooth transition with the sides of the watch case 1.

A bridging member 7 has integral shoulders 8 which are situated one on each side of a central plate portion 9. Each shoulder 8 is firmly secured to the base-plate portion Sc and the end of the inner member 5d by turned down ears 8a, at each side of the bracelet, which are integral with shoulder 8. Two of these ears 8a, one on each side of the bracelet (i.e. depending from respective shoulders 8), are schematically indicated by broken lines in Fig. 1. The end portion 6 is secured to the shoulders 8 of the bridging member 7 by means of turned down ears 10, shown in Fig. 1, and each shoulder has a lug portion 8b which projects between adjacent pairs of ears 10 to prevent any pull-out.The turned down ears 8a and 10 are pressed or clamped firmly to secure the bridging member 7 and the end portion 6 to the end of the bracelet 5.

As shown in Fig. 3, the step faces 2a, 2b of the stepped profile of the integral tab 2 engage with a corresponding profile on the end of the bracelet 5.

Step face 2a engages with the end of the inner member 5b, and step face 2b engages with edge 5e of the cut-out in the base-plate portion 5c. This assists in providing a rigid and secure engagement between the end of the bracelet and the watch case when these parts are secured to one another as shown in Fig. 3 (and as described below).

The central plate portion 9 is integral with side walls 9a which define an aperture 11 for receiving the tab 2 (see Fig. 2). The central plate portion 9 also includes a folded part or detent 9b, which is struck from the plate portion 9. The detent 9b has a generally V-shaped cross-section with one of the limbs of the V extending freely in a direction away from the end of the bracelet and inclined towards the inner (i.e. wrist-facing) side of the bracelet.

This free-limb terminates in a sharp edge 9c which is intended to cooperate with the undercut or inclined wall 4 of the recess 3 in the tab 2. The detent 9b is strengthened, across its flexing axis 12, by a generally C-shaped pressing 13. This pressing raises a C-shaped ridge 1 3 on the upper surface of the plate portion 9, as shown in Figs. 1 and 2 (the section in Fig. 2 does not pass through the pressing 13). The effect of this pressing 13 is to strengthen flexure of the detent 9b in the region of axis 12.

In the plan view of Fig. 4, an arcuate cut away portion 14 of the bridging member 7, i.e. which is cut away from the plate portion 9, can be seen more clearly. This results in the curved edge shown in Fig. 1. Fig. 4 also shows a small cut away or notch 1 5 in the leading edge 9c of the detent 9b. This notch 15 is provided to facilitate parting of the edge 9c of the detent 9b from the undercut or inclined side wall 4 of the recess 3 in the tab 2, i.e. to separate the watch case 1 from the end of the bracelet 5. By inserting a tool (such as the blade of a watchmaker's screwdriver, or a metal rod, or the like) in notch 1 S and by levering against the detent 9b, using the side wall 4 as a fulcrum, the detent 9b can be flexed and disengaged from the wall 4 of the recess 3 in the tab 2. However, notch 15 is optional and it may be omitted.

As shown in Fig. 2, the watch case 1, having its front face 1 6 pointing downwardly as shown in the drawing, is located so that the tab 2 is ready for insertion into the aperture 11 of the bridging member 9 on the bracelet 5. On inserting the tab 2, the detent 9b is deflected upwardly until the edge 9c passes over the edge of the side wall 4 of the tab recess 3. The edge 9c then springs resiliently into the recess 3 whereby the sharpened edge 9c engages the corner of the recess 3 adjacent the inclined wall 4, i.e. as shown in Fig. 3. This results in a close fit between the leading edge of the end portion 9 of the bracelet and the side of the watch case (i.e. in the region marked 17 in Fig. 3) to give a pleasing one-piece effect.

Fig. 5 shows the underside view of an alternative embodiment of a watch case and strap assembly according to the invention. This assembly, though much simpler than the embodiment described above (particularly in respect of the strap end construction), functions in a similar manner.

Thus the underside of watch case 21 again includes an integrally-formed tab 22 of a planar construction bearing a recess 23. In this instance, however, the recess 23, which is defined by inner face 24a and outer face 24b, has a substantially V-shaped cross-section; the outer face 24b being more nearly vertical relative to horizontal tab 22 than face 24a. Except in the region of recess 23, the thickness of the tab in this embodiment is uniform from the point at which it joins the watch case to its leading end.

The bracelet 25 may be of any appropriate construction. As an example (not shown), the bracelet may be formed of transverse first and second interlocking oppositely-facing U-shaped links. In that instance, it is contemplated that the alternate first links would form the outer surface of the bracelet and would bear tabs as extensions of the inwards-facing arms of the U-shape. The interposed second links would then include apertures in the central portion of the U-shape to accept the tabs and that portion of the U-shape would form the inner surface with the turneddown tabs. Whatever detailed construction of bracelet 25 is adopted, the end 40 adjacent to watch case 21 is formed with an inclined surface 42 intended to fit flushly against watch case 21 (as described in more detail later in respect of Figs.

6 and 7).

The bridging member 27 has integral side walls 29a which are situated one on each side of central plate portion 29. The side walls 29a are turned over to form flanges 28 which lie flat on the inner face of bracelet 25 and are firmly secured to the bracelet e.g. by brazing or welding. The inner face of bracelet 25 in that region, the side walls and the central plate portion 29 together form a tightfitting aperture 31 for receiving tab 22 (see also Fig. 6). A detent 29b is struck from the plate portion 29 of bridging member 27. This detent is of generally similar construction to detent 9b of Fig. 1, but differs from detent 9b in not including a reinforcing C-shaped pressing. In a similar way to the assembly of the previous embodiment, detent 29b terminates in a sharp edge 29c which is intended to cooperate with inclined face 24b of recess 23.

As may be seen more clearly in Fig. 8, the bridging member 27 includes outwardly extending arms 30 surrounding detent 29b. Relatively large gaps between the sides of detent 29b and arms 30 allow for minor sideways deflections of detent 29b, when it is urged upwards, without its movement being restricted by abutment against one of arms 30. As has already been described for the previous embodiment in respect of notch 15, a notch 35 allows the detent 29b to be flexed by leverage from a suitable tool and thereby to be disengaged from recess 23. However such disengagement would normally be infrequent and the attachment between watch case 21 and bracelet 25 may be regarded as semi-permanent.

Thus detent 29b whilst being formed of metal sufficiently flexible to allow such forceable disengagement to occur, is rigid enough to resist disengagement under light pressure.

As shown in Fig. 6, the watch case 21 has its front face 36 pointing downward. Tab 22 is shown ready for insertion into aperture 31 between bridging member 27 and bracelet 25. Fig. 7 is a similar view after bracelet 25 has been pushed fully home on tab 22.

In this instance, a pleasing one-piece effect is achieved by outer surface 40 of the strap 25 being in the same plane as bevel 38 on watch case 21.

To achieve this alignment, tab 22 is at the same angle to the front 36 of the watch case as the bevel 38 and is set back from the front of the watch by a distance corresponding to the thickness of watch strap 25.

The fastening means described above may be used on other forms of bracelet and watch case for semi-permanently attaching the watch case to the bracelet.

Claims (11)

1. A bracelet and watch case assembly wherein the watch case has an integral tab provided with the recess, and wherein at least one end of the bracelet has a bridging member which defines an aperture for receiving said tab, said bridging member including a detent which is resiliently deflectable, upon insertion of said tab in said aperture and which thereafter engages the recess in said tab to secure said one end of the bracelet to the watch case.

2. An assembly according to claim 1 wherein said detent is an integral part of the bridging member.

3. An assembly according to claim 2 wherein said detent is struck from a plate portion of the bridging member and is mainly deflectable with respect to a flexing axis.

4. An assembly according to any one of the preceding claims wherein said detent has a folded form with a substantially V-shaped cross-section, one of the limbs of the V-shape extending freely in a direction away from the end of the bracelet and inclined towards the inner side of the bracelet.

5. An assembly according to claim 4 wherein the free limb terminates in a sharpened edge for engaging a corner of the recess in said integral tab.

6. An assembly according to claim 5 wherein said sharpened edge has a central cut away portion or notch.

7. An assembly according to any one of the preceding claims wherein the recess in said integral tab has an inclined or undercut wall portion for engaging said detent.

8. An assembly according to claim 3 or any of claims 4 to 7 as dependent on claim 3 wherein said detent is strengthened across the flexing axis by a pressing.

9. An assembly according to claim 8 wherein said pressing is in the form of a generally C-shaped ridge.

10. An assembly according to claim 7 wherein the recess is substantially V-shaped.

11. An assembly according to any of the preceding claims in which the outer face of the bracelet and adjacent portion watch case are aligned to provide a smooth transition at their junction and thereby give a substantially onepiece appearance in that region.

1 2. A bracelet and watch case assembly substantially as herein described with reference to Figures 1 to 4 of the accompanying drawings.

1 3. A bracelet and watch case assembly substantially as herein described with reference to Figs. 5 to 8 of the accompanying drawings.