US3376619A

US3376619A - Locks for bracelets

Info

Publication number: US3376619A
Application number: US560190A
Authority: US
Inventors: Brunet Louis
Original assignee: Zuccolo Rochet et Cie SA
Current assignee: Zuccolo Rochet et Cie SA
Priority date: 1965-06-30
Filing date: 1966-06-24
Publication date: 1968-04-09
Anticipated expiration: 1985-04-09
Also published as: DE1960093U; FR1448990A

Description

Apz'ifi 9, 1968 BRUNET 3,376,619

LOCKS FOR BRACELETS Filed June 24, 1966 we go INVENTOR Lou/s BRUNET' 2 3 I 4 iffy/0x 1 Unite States Patent 3,376,619 LOQKS FOR BRACELETS Louis Brunet, Annecy-le-Vieux, France, assignor to Societe Zuccolo, Rochet 8: Cie, Annecy, Haute- Savoie, France, a corporation of France Filed June 24, 1966, Ser. No. 560,190 Claims priority, application France, June 30, 1965,

22, 1 Claim. (Cl. 24-241) ABSTRACT OF THE DISCLOSURE This invention relates to resiliently extensible couplings for connecting the ends of a bracelet, watch strap or belt of the type in which one end is equipped with a resilient hooking and locking device engaging -a transverse bar attached to the other end of the strap.

This kind of booking or locking device usually c0mprices a frame attached by one of its transverse edges to the end of the watch strap, and within this frame there is guided, to slide longitudinally, that is to say in the direction of the length of the watch strap or bracelet and against the influence of a spring, a flat sleeve mounted astride the second transverse edge of the frame. On this sleeve there is hinged a cover which engages with a slotted bar attached to the other end of the strap, said cover being capable of folding back on to the sleeve, with which it locks, enclosing the bar.

A lock of this kind is rather thick and is not suitable for watch straps for very thin watches.

To eliminate this disadvantage the resilient lock according to the invention, which is of the type having a bar attached to one end of the watch strap, and a hooking or locking device which is attached to the other end of the strap and engages with said bar, is characterized in that said hooking or locking device consists of two flat elements, which slide the one within the other after the manner of a drawer in a chest of drawers, said elements containing between them a spring, the arrangement being such that the open faces of said sliding elements face in opposite directions and wherein the external sliding element is equipped in its open face with two longitudinal guide rails for retaining the internal sliding element, to which is attached a locking plate engaging with said bar and which, when in the locked position, rests between said longitudinal guide rails without adding any extra thickness.

In a preferred version of the invention, the locking plate is hinged to the internal sliding member by means of a transverse spindle and a gap is left between said spindle and the edge of the sliding member to accommodate the bar, the total height of the hinge being no greater than the height of the internal sliding member.

This gap or throat is preferably formed by bending the adjacent transverse edge of the internal sliding member at the level of the bottom of the external sliding member, in such a way that there is at the same time formed a mechanical stop for limiting the travel of the internal sliding member when the latter is fully retracted.

Finally, the length of the internal sliding member,

measured in the longitudinal direction of the bracelet or strap, is less than the length of the external sliding memher by an amount sufficient to leave a gap, between the end of the internal sliding member when the latter is fully retracted and the bar which attaches the external sliding member to the watch strap, to accommodate the locking lip of the locking plate, which preferably displays instructions indicating the direction of movement for opening the lock.

In this way there is obtained a lock which is very fiat, the total height being less than half that of the previously known locks.

There will now be described by way of example and with reference to the attached drawings, a version of the lock according to the invention.

In the drawings:

FIGURE 1 is a perspective view or" the lock in the open position, showing the two strap ends of the bracelet,

FIGURE 2 is a longitudinal cross-section of the lock in the closed position.

FIGURE 3 is a perspective view of the spring.

The exploded view of FIGURE 1 shows how end 1 of the bracelet terminates in a stirrup 2 which has two arms 3 and 4- at the sides, joined together by a. bar '5, adapted to engage with the lock. The latter is hinged to the other end 6 of the bracelet or strap by means of hinge 7 through which passes spindle 8 fixed to the lock.

The lock comprises slider 10 which slides inside guide frame 9, these two parts having openings facing in opposite directions, for example the opening of the slider .10 faces downwards whereas that of the guide frame 9 faces upwards.

The guide frame 9 has a bottom 11 and two side guides 12 and 13, which terminate in two

extended edges

14 and 15 situated in a plane parallel to the bottom 11 of the guide frame and running longitudinally, that is to say in the direction of the length of the bracelet.

These guiding

edges

14 and 15 do not extend far across the width of the bracelet, but extend far enough to form retainer rails for the slider 10, the arrangement being such that the slider 10 can slide in guided fashion within the guide frame 9. The slider 10 has a flat body portion with two flanks 14' and 15'. Between the front wall 16 of the slider 10 and rear wall 17 of the guide frame 9 there is a flat coil spring which pushes the slider 10 inwards in the guide frame 9 in the direction toward the hinge 7.

This coil spring is represented on a larger scale in FIGURE 3, and consists of a steel wire 25 coiled to conform to the internal cross-section of the lock.

The slider 10 has a rear portion 18 bent into L-shape and terminating in a bent sleeve 19 which accommodates pin 20 and thus forms the central bush of the hinge for locking plate 23. Two outer bushes 21 and 22 of this hinge are formed by bending around the ends of the locking plate 23. Thus the locking plate 23 forms a cover plate for the lock, and its resilient lip 24 engages, when the lock is closed, over the edge of the front face 16 of the slider 10. The width of the locking plate 23, which is made of rather thin sheet metal, is equal to the distance between the two

retainer flanges

14 and 15, so that the plate 23 just fits between these two flanges. To join together the two ends of the bracelet and close the lock, the locking plate 23 is first introduced between the bar 5 and the stirrup 2. The locking plate 23 is then swung inwards, bringing the bar 5 to rest in the recessed rear portion 18 of slider 10. Further rotation of the locking plate 23 brings it down between the edges of the

retainer flanges

14, 15 whereby no increased thickness of the lock results, as shown in FIGURE 2, which illustrates the lock in the closed position. The spring 25 pushes the slider It all the way into the guide frame 9.

FIGURES 1 and 2 show how the

retainer flanges

14 and 15 terminate short of the hinge 7 to leave a gap 27 between the front edge 26 of the locking plate 23 and the hinge 7, said gap being wide enough for the wearer of the bracelet or strap to insert his fingernail in order to open the lock.

, The advantage provided by the lock described here, applied to a bracelet consisting of articulated elements, bearing in mind that it can if desired be applied to a bracelet of another kind or to a belt or the like, is that the lock is very thin due to the arrangement of a slider sliding within a guide frame after the manner of a drawer in a chest of drawers, and wherein the cover plate rests between the two guiding flanges of the guide frame without producing any extra thickness.

I claim:

1. A resiliently extensible lock, particularly for watch straps, of the type which comprises a bar attached to one end of the bracelet, and a hook or lock attached to the other end of the bracelet or watch strap and engaging with said bar, the lock including a hooking or locking device consisting of two fiat elements which slide the one within the other after the manner of a drawer in a chestof-drawers, and containing between them a spring wherein the two elements have openings facing in opposite directions and wherein moreover the external element in the form of a guide frame has in its open face two longitudinal guide rails which act to retain an internal sliding member equipped with a locking plate which engages with the bar and which, when the lock is closed, rests between the two guide rails without entailing any extra thickness, said locking plate being hinged to the internal sliding member by suitable means so that there is left between said hinge and the end of said internal sliding member a throat adapted to snugly accommodate the bar, wherein the total height of the hinge is no greater than that of the internal sliding member, said throat beingv ber being less than that of the external guide frame by' an amount sufficient to leave a gap, when the internal sliding member is fully retracted, between the front edge of the internal Sliding member and the attachment bar which secures the other end of the bracelet to the external guide frame, to accommodate the locking clip of the locking plate, said bar having ,a fiat surface abuttingly engageable with the said transverse edge of the internal slider to prevent flexing of an attached watch strap from causing the said bar to pivot upwardly about the hinge means a sufficient amount to engage the under surface of the locking plate and inadvertently unlock the lock.

References Cited UNITED STATES PATENTS 1,852,462 4/1932 Johnson 2471 1,892,281 12/1932 Kestenman. 2,006,047 6/1935 Johnson 2471 2,333,048 10/ 1943 Schoeninger 24239 DONALD A. GRIFFIN, Primary Examiner.