This application claims priority from European Patent Application No. 11170091.0 filed Jun. 16, 2011, the entire disclosure of which is incorporated herein by reference.
The invention concerns a triple security unfolding clasp for holding both ends of a bracelet or strap, said clasp including a buckle around both sides of which are hinged a first strand and a second strand, each carrying a shouldered locking pin or eye respectively and arranged to cooperate in a closing position of said clasp with a complementary locking eye or pin respectively comprised in said buckle, and said buckle comprising a first pusher and a second pusher which can move in the same direction, each against resilient return means returning said pushers to a locking position and each arranged to control, directly or indirectly, the forward or backward movement of two bolts, which are antagonistic in said direction to opposite bolts controlled by the other of said pushers, each said bolt being arranged to immobilise, in said closing position, at said complementary locking eye or pin respectively, a constricted portion comprised in said locking pin or eye respectively, and the individual travel of each of said pushers being smaller than a release travel during which at least two antagonistic bolts release, in an opening position, said constricted portion of at least one of said locking eyes or pins respectively, and the combined travel of said pushers being greater than or equal to said release travel.
The invention also concerns a bracelet or wristband including a clasp of this type.
The invention concerns the field of securing objects, in particular to the person, and concerns more specifically the fields of horology, and jewellery.
The invention will be described more specifically for the field of horology-jewellery, for fastening bracelets, wristbands or wristwatches.
Numerous clasps are known for bracelets, in particular for wristwatches or for jewellery, which comprise unfolding moveable strands.
In many clasps, called triple clasps, i.e. including two strands hinged to a buckle on which they are folded down, each strand including a pin cooperating in a locking position with one eye of the buckle, the buckle is fitted with two resiliently mounted pushers. Often, pressure on only one of the two pushers can can cause the clasp to open, which is unsatisfactory from a safety viewpoint. Likewise, after a first strand has been locked, it is common for the closing of the other strand to have the effect, by separating the pushers, of releasing the strand which was already locked and which was providing provisional security. Certain designers have overcome this latter defect by setting a sequential closing order of the strands, which is inconvenient for the user.
Various clasp devices propose solutions to this problem. Thus CH Patent No. 670 941 in the name of CORNU & CIE SA discloses a clasp with a small number of components, which utilises the elastic deformation of pusher branches in the shape of tuning forks, the ends of which form retaining stops for the strands. EP Patent No. 0 549 846 in the name of GTF SRL discloses a bolt device comprising bolts, having concave paths on which a V-shaped spring abuts, which project outside a case to cooperate with hooks comprised in the strands, and for unlocking, a single pusher pushes ramps comprised in these bolts, against the spring which works by buckling. JP Patent No. 9000320 in the name of CITIZEN discloses a clasp with four bolts each provided with a ramp-shaped cam, arranged in pairs opposite springs and operated against these springs by two pushers each comprising two antagonistic ramps.
CN Patent No. 201278878Y in the name of HUADONG GUAN presents a clasp with two pushers pushed back by a first spring, each carrying two claws pushed outwards by a spring perpendicular to the first spring.
In short, the solutions proposed are often complex or fragile, since they are essentially based on the elasticity of certain components.
The invention proposes to make a safety clasp, which guards against untimely opening, or against reopening, when, for example, after one strand of the clasp has already been folded down and a first pin locked onto the buckle, the closing of the second strand and insertion of the pin carried thereby causes the first pin to unlock and the clasp to reopen and even the watch or object connected to the bracelet to fall.
Therefore, the invention concerns a triple security unfolding clasp for holding two ends of a bracelet or strap, said clasp comprising a buckle around either side of which are hinged a first strand and a second strand, each carrying a shouldered locking pin or eye respectively, and arranged to cooperate in a closing position of said clasp with a complementary locking eye or pin respectively comprised in said buckle, and wherein said buckle includes a first pusher and a second pusher which can move in the same direction, each against resilient return means returning said pushers towards a locking position and each arranged to control, directly or indirectly, the forward or backward movement of two bolts, which are antagonistic in said direction against opposite bolts controlled by the other of said pushers, each said bolt being arranged to immobilise, in said closing position, at said complementary locking eye or pin respectively, a constricted portion comprised in said locking pin or eye respectively, and the individual travel of each of said pushers is smaller than a release travel during which at least two antagonistic bolts release, in an opening position, said constricted portion of at least one of said locking pins or eyes respectively, and the cumulated travel of said pushers is greater than or equal to said release travel, characterized in that said first pusher simultaneously, directly and integrally drives a first primary bolt opposite a first locking pin or eye respectively, and a second primary bolt opposite a second locking pin or eye respectively, whereas said second pusher independently drives a first secondary bolt opposite said first locking pin or eye respectively, and a second secondary bolt opposite said second locking pin or eye respectively, so that only the combined actuation of said two pushers causes the movement of all of the bolts through their entire release travel to release both said first locking pin and said second locking pin or eyes respectively, and so that one of said two secondary bolts remains in the locking return position during the insertion of one of said locking pins or eyes respectively towards said complementary locking eye or pin respectively corresponding thereto, to take a locking position.
According to one feature of the invention, when the user presses, said second pusher is arranged to push, in said direction and via a bearing surface comprised in said second pusher, a first bearing surface of said first secondary bolt, and a second bearing surface of said second secondary bolt, so as to move said first secondary bolt and said second secondary bolt parallel to each other.
According to another feature of the invention, in the absence of any action by the user on one of the pushers, said first secondary bolt and said second secondary bolt can move independently of each other against resilient return means.
According to yet another feature of the invention, a first said complementary locking eye or pin respectively, is delimited by the cooperation of said first primary bolt and said first secondary bolt, and a second said complementary locking eye or pin respectively is delimited by the cooperation of said second primary bolt and said second secondary bolt, and each said complementary locking eye or pin respectively constitutes a chamber of variable volume, between an opening position in which it is able to let pass a head comprised in said locking pin or eye respectively corresponding thereto, and a closing position in which it is able to grip said constricted portion of one said locking pin or eye respectively corresponding thereto, between jaws formed by bearing surfaces comprised in said bolts concerned, and immobilising said head on the opposite side to said strand carrying said locking pin or eye respectively concerned, relative to said jaws.
The invention also concerns a bracelet or wristband including a clasp of this type.
The invention will be become clearer upon reading the following detailed description, with reference to the annexed drawings, in which:
The invention concerns the field of securing objects, in particular to the person, and concerns more specifically the fields of horology, and jewellery.
The invention will be described more specifically for the field of horology-jewellery, for fastening bracelets, wristbands or wristwatches.
The invention concerns a triple security unfolding clasp for holding two ends 200, 300 of a bracelet 100 or a strap. “Strap” is to be understood in the broad sense and may be a harness, a load retaining strap or other type of strap fastener.
This description more specifically concerns a clasp 1 for a wristwatch or bracelet 100, but this preferred application is in no way limiting.
As seen in
As seen in
This buckle 10 includes a first pusher 11 and a second pusher 12 which can move in the same direction D, each against resilient return means 13, 14 returning said pushers to a locking position, and each arranged to control, directly or indirectly, the forward or backward movement of two bolts 15, 16 for the first pusher 11, two bolts 17, 18 for the second pusher 12, which are antagonistic in direction D to opposite bolts, respectively 17, 18 and 15, 16 controlled by the other pusher 12, 11. This direction D is shown in the Figures in a preferred embodiment in which, in a conventional manner, it is perpendicular to the direction of elongation of bracelet 100.
In a particular version illustrated in the Figures, the first pusher 11 and the second pusher 12 are substantially coplanar and preferably coplanar.
Each of these bolts 15, 16, 17, 18 is arranged to immobilise, in this closing position, at complementary locking eye 8, 9 or pin respectively, the constricted portion 6A, 7A of the locking pin 6, 7 or eye respectively concerned.
The individual travel of each of pushers 11, 12 is smaller than a release travel during which at least two antagonistic pins release, in an opening position, the constricted portion 6A, 7A of at least one of the locking pins 6, 7 or eyes respectively.
The combined travel of pushers 11, 12 is greater than or equal to this release travel.
According to the invention, and as particularly seen in
Whereas second pusher 12 drives, independently of each other, a first secondary bolt 17 opposite said first locking pin 6 or eye respectively, and a second secondary bolt 18 opposite said second locking pin 7 or eye respectively, so that only the combined actuation of these two pushers 11, 12 causes the movement of all of bolts 15, 16, 17, 18 through their entire release travel to release both first locking pin 6 and second locking pin 7 or eyes respectively, and so that one of the two secondary bolts 17, 18 remains in the locking return position during insertion of one of said locking pins 6, 7 or eyes respectively towards the complementary locking eye 8, 9 or pin respectively corresponding thereto, to take a locking position.
Preferably, as seen in
Preferably, according to the invention, in the absence of any action by the user on one of pushers 11, 12, the first secondary bolt 17 and the second secondary bolt 18 can move independently of each other against resilient return means. This arrangement is particularly advantageous, since it allows one of said two secondary bolts to be kept in the locking position. For example, it keeps an already engaged pin 6 or 7 locked, when the operator handles the strand carrying the other pin which is not yet engaged in the clasp, inserts the pin in the corresponding eye and consequently tends to move the bolts away from said eye to allow said other pin to pass, without, however, releasing the pin which is already engaged and locked. This also means that when, during insertion of the other pin, the first pusher moves away from the locking position, the secondary bolt which was holding the already engaged pin is not affected by this manoeuvre and remains in the locking position.
Advantageously, as seen in
It is clear that the complementary locking eyes 8, 9 or pins respectively are chambers of variable geometry, each delimited by a primary bolt actuated by the first pusher 11 and by a secondary bolt actuated by the second pusher, said primary and secondary bolts 12 being arranged to behave like jaws immobilising the corresponding locking pins 6, 7 or eyes respectively. Thus, a first complementary locking eye 8 or pin respectively is delimited by the cooperation of the first primary bolt 15 and the first secondary bolt 17 and a second complementary locking eye 8 or pin respectively is delimited by the cooperation of the second primary bolt 16 and the second secondary bolt 18. Each complementary locking eye 8, 9 or pin respectively forms a chamber of variable volume, between an opening position in which it is capable of allowing a head 6B, 7B to pass, respectively comprised in the corresponding locking pin 6, 7 or eye, and a closing position in which it is capable of gripping the constricted portion 6A, 7A of said locking pin 6, 7 or eye respectively corresponding thereto, between jaws formed by bearing surfaces comprised in said bolts concerned, while immobilising the head 6B, 7B on the opposite side to the strand 2, 3 carrying the locking pin 6, 7 or eye respectively concerned, relative to said jaws.
The first pusher 11, like the second pusher 12, can move in direction D between a first stable rest position PSR in which the extension thereof relative to buckle 10 is maximum, and in which it does not cooperate with any of locking pins 6, 7 or eyes respectively, another second intermediate stable locking position PSI in which it immobilises at least one of locking pins 6, 7 or eyes respectively, and a third transitory release position PTL when the user maintains pressure and in which the pusher tends to release locking pins 6, 7 or eyes respectively.
In a particular embodiment, the first stable rest position PSR and said second intermediate stable locking position PSI of first pusher 11 are the same. Likewise, the first stable rest position PSR and said second intermediate stable locking position PSI of the second pusher 12 are the same.
The first pusher 11 can move from its first stable rest position to its third transitory release position in a first actuating direction D1, and the second pusher 12 can move from its first stable rest position to its third transitory release position in a second actuating direction D2 opposite to first direction D1.
Only as regards the first pusher 11, this third transitory release position PTL may also be reached, not via action by the user on the pusher(s), but via action of the user on one of strands 2 or 3.
However, the particular kinematics belonging to the second pusher 12, which pushes secondary bolts 17 and 18 independently of each other, are irreversible. The complete return of one of the two secondary bolts 17 and 18 in direction D1 opposite to direction D2 has the effect of returning the second pusher 12 to its first stable rest position PSR if, at the secondary bolt concerned, the pin is not engaged with the corresponding eye, and the other secondary bolt is then entirely free to move without any effect on the bolt, which has thus pushed the second pusher 12 back to its stable rest position PSR.
The second intermediate stable rest position PSI is occupied by the second pusher 12 when each pin 6, 7 or eye respectively is engaged in the corresponding eye or pin respectively at the same time.
Preferably, each bolt tends to immobilise the corresponding pin or eye respectively in traction. Each pusher therefore drives hook-shaped bolts.
As seen in
The bearing surfaces 15A, 16A, 17A, 18A may, as seen in
This hook configuration ensuring traction locking ensures that the locking pins are held properly and also that the components of clasp 1 are kept inside said clasp.
In order to ensure both that the components are held securely and the travels are limited, the invention comprises a certain number of stop members. Thus the mobility of the first pusher 11 relative to buckle 10 is limited by the travel of a stop 24 in a chamber 23. Likewise, the mobility of the first secondary bolt 17 and the second secondary bolt 18 relative to buckle 10, or more precisely the slides 31 and 32 which carry said bolts, is limited by the travel of a stop 27, 28 in a chamber 25, 26, as seen in
Likewise, the mobility of the actual second pusher 12 relative to buckle 10 is limited by the travel of at least one stop 27, 28 in a chamber 38, 39.
In a particular embodiment, seen in
In the version illustrated in the Figures, these slides 31, 32 are called “female” since they are arranged to form guide means for the male pusher 11. Thus, buckle 10 comprises bearing surfaces 51, 52 which guide in translation in direction D, and which are arranged to cooperate with first complementary guide surfaces 31A, 32A comprised in secondary bolts 17, 18 or slides 31, 32 carrying said secondary bolts 17, 18. These secondary bolts 17, 18 or slides 31, 32 further include second guide surfaces 36B, 37B arranged to cooperate with each other, or with a guide element in direction D comprised in buckle 10 and/or second pusher 12 and/or first pusher 11.
In a particular embodiment illustrated in
In a particular embodiment illustrated in
The particular design of the pusher guide surfaces and the bolts of the clasp according to the invention guarantee flexible and precise operation without any butting.
The clasp according to the invention is also particularly robust and is well suited to fastening the bracelet of an expensive watch or piece of jewellery.
The invention also concerns a bracelet 100 including a clasp 1 of this type.
Number | Date | Country | Kind |
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11170091.0 | Jun 2011 | EP | regional |