SAFETY LOCK

Abstract: A safety lock for use in jewel and ornament chains and for purposes in which a particularly high locking reliability is required from the lock. The lock is integral in structure and it comprises a locking flap (1), a locking bow (2) and a flexible ring (3). The locking operation of the safety lock takes place in two stages. The first locking stage is carried out in the inner space of the lock by locking the locking bow (2) inside a connection ring (6), whereas the second stage is based on the flexible properties and compression of the locking flap (1), whereby the connection ring (6) can be displaced from the inner space of the lock through the T-shaped opening of the locking flap (1) into the final connection point of the locking bow (2), whereafter the locking flap (1) is pressed against the locking bow (2), simultaneously closing the connection ring within the locking bow (2).

Description: Safety lock The invention relates to a safety lock for jewel and ornament chains as well as for purposes in which the locking effect of the lock should be especially reliable, the lock being manufactured of a flexible precious metal or other metal material resis¬ tant to shaping by bending with various techniques in such a way that the safety lock is structurally inte¬ gral and comprises a locking flap, a locking bow and a flexible ring. In order that the safety lock could be attached to the chain reliably and without deterio¬ rating the flexibility of the lock by thermal treat¬ ment, the safety lock is further provided with a so called connection lock the reliability of the locking effect of which is equal to that of the safety lock. The connection lock can be manufactured of the same materials with the same techniques as the safety lock. The connection lock is shaped so as to be structurally integral, and it comprises two lock housings which are passed into the safety lock position simultaneously. With a few exceptions, the locking reliability of the locks of ornament chains has proved to be poor. Many of them are broken even after a short-time use or get into disorder and inoperative in some other way. The object of the invention is to eliminate these common disadvantages of jewel and ornament chains and to make the lock not only easy to operate and easy to use but also so reliable that the locking will not fail at any stress stage, with the exception of intentional breakage through violence. For the achievement of this object, the safety lock described in the beginning is characterized in that the flexible ring comprises the flexibly yielding locking flap, which is provided with a T-shaped open- ing, the rather broad shape of the locking flap being determined by the width of the T-shaped opening of the locking flap, the width of the T-shaped opening being determined partly at the manufacturing stage by the width of the locking tip when the locking bow is bent so as to be passed within the locking flap and partly by the space required by a connection ring of the chain when it is being passed through the T-shaped opening of the locking flap into the inner space of the safety lock; and the locking bow, which is so shaped that the tip portion widens in an arched manner into a droplike silhouette shape, being outwardly curved at the tip thereof, and the locking bow is bent so that said widened tip portion of the locking bow is in a closed position near to the inner surface of the locking bow, which goes through the T-shaped opening of the locking flap in an arched manner, and adjacent to the T-shaped opening inside the safety lock, and that the first stage of the connection locking is car¬ ried out in such a manner that the connection ring of the chain is positioned behind the widened portion of the tip of the locking bow, whereafter the connection ring is pulled and displaced past the tip in such a manner that the locking bow is locked within the inner space when the lifted locking tip returns to the closed position, whereafter at the second stage by pressing down the locking flap, the connection ring can be freely displaced out through the T-shaped open¬ ing into the final locking position, whereby the lock¬ ing reliability so obtained is such that the same steps as at the locking stage in reverse order are re¬ quired for unlocking. For the attachment of the safety lock to a chain without deteriorating its flexibility, the in¬ vention is further concerned with a so called connection lock. This connection lock, which can be fastened to the safety lock already at the manufactur¬ ing stage, should not only be easy to attach but also possess an especially high locking reliability. The connection lock can be manufactured of any flexible precious metal or other metal resistant to tensile stress and to shaping by bending by various tech¬ niques. The connection lock is manufactured in such a way that it is structurally integral and comprises two lock housings which can be passed into the safety locking position simultaneously. For the achievement of this object, the connection lock is characterized in that the connection housing positioned at one end of the body and provided with a lock housing at the tip of the body thereof is fastened by pressing the tip portion of the lock against the body of the lock after the connection, whereby the first connection housing is formed, while the chain connection housing of the connection lock remains in the open position, which connection housing is pressed to the closed po¬ sition after having been attached to the chain, whereby the second housing is formed when both housings of the lock are passed to the safety locking position simultaneously, by which measure the locking reliability of the lock equals to that of the safety lock, and the lock unlocks only by releasing the lock¬ ing tip from the lock housing by means of a lifting movement. In the following a few embodiments of the safe¬ ty lock according to the invention will be described in more detail with reference to the attached drawing, wherein Figure 1 is a side view of the safety lock in the initial position and of the starting stage of the locking operation when a connection ring 6 of the chain is pushed beside a locking bow 2 into the T- shaped opening of a locking flap 1. Figure la illustrates the following stage of the locking operation, wherein the connection ring 6 of the chain is pressed sufficiently deep inside the lock for a widened tip portion 2* of the locking bow 2 of the safety lock to be snapped into the inner space of the connection ring 6 of the chain. Figure lb illustrates the most important stage of the locking operation, that is, the passing of the locking bow 2 inside the connection ring 6 of the chain at the middle stage of the passing step. By means of the connection ring 6 of the chain, the arched, rather broad tip portion 2' of the locking bow 2 is lifted upwards so that it is possible to turn the connection ring 6 of the chain into an opening be¬ tween the tip portion 2* and the locking bow 2. Figure 2 illustrates a locking stage at which the locking bow is displaced within the inner space of the connection ring of the chain. Figure 2a illustrates the locking procedure. In the figure, the locking flap 1 is pressed down into the extreme point allowed by the flexible ring 3, whereby the gap at the connecting point 3' of the flexible ring 3 is closed. When the locking flap 1 is in the down-pressed position, the connection ring 6 of the chain can be freely passed through the locking flap 1, turned into a normal transverse position and released from the compression of the locking flap 1, while the locking flap 1 is returned to the initial position. Figure 3 illustrates the end result of the locking operation, whereby the lock has returned to the initial position after completed connection. Figure 3a is a top view of the same end result of the locking operation as in Figure 3. This figure also shows the locking flap 1 from the top and the T- shaped opening. The widened portion of the T-shaped opening is needed at the manufacturing stage of the lock in order that the widened tip portion 2* of the locking bow 2 could be passed inside the lock when the product is being shaped by bending. Figure 3b is a top view of the safety lock and a connection lock attached to it. The connection lock is not closed and passed into the safety locking po¬ sition until the chain has been attached thereto. Figure 3c is a cross-sectional view of the safety lock along the line a-a shown in Figure 3b when the lock is in the initial position. The figure shows the shape of the tip portion 2' of the locking bow 2 and the width thereof as compared with the width of the opening of the locking flap 1. In the following a few embodiments of the con¬ nection lock according to the invention will be de¬ scribed in more detail with reference to the attached drawing, wherein Figure 4 is a side view of the connection lock according to the invention at a bending stage when the locking tips 7' and 8' of the connection lock are apart from the body for enabling the connection. The broader half of the connection lock is indicated with the reference numeral 7, the lock housing end thereof with the reference numeral 7', the narrower half with the numeral 8, and the locking end correspondingly with the numeral 8' . Figure 4a is a side view of the connection lock after the completion of the connection of the connection lock to the flexible ring 3 of the safety lock and after the tip portion provided with the lock housing 7' has been pressed against the inner body of the connection lock into a closed position and at which stage the first lock housing is formed while the locking tip 8' further remains in an open position. Figure 4b is a side view of the connection lock after a chain has been connected to the locking bow 8, and the tip portion 8' of the locking bow has been pressed inside the lock housing 7' into the safety locking position. It further appears from the figure that the connection lock comprises two separate lock housings which are formed by the locking tips 7' and 8' . The function of the separate lock housings is to prevent the rotary motion of the ring. Figure 4c is a top view of the connection lock in the closed locking position. It appears from the figure that the lock can be shaped so that when the connection is made to a larger ring, in this particu¬ lar case to the flexible ring 3 of the safety lock of the invention, this half of the connection lock may be broader so that it withstands better the wear exerted on the ring positioned first adjacent to the lock. The other half of the connection lock may be narrower be¬ cause the chain to be attached thereto may be very thin. The locking operation of the safety lock shown in Figures 1, la, lb, 2, 2a, 3, 3a, 3b, and 3c takes place in two stages, comprising the closing of the locking bow 2 within the connection ring 6 of the chain in the inner space of the lock, and the dis¬ placement of the connection ring 6 from the inner space of the lock through the T-shaped opening of the locking flap 1 to the final locking point of the locking bow 2. In Figure 1, the safety lock is shown in the initial position, from where the locking operation is started by passing the connection ring 6 of the chain inside the T-shaped opening of the locking flap 1 be¬ side the locking bow 2. In Figure la, the connection ring 6 of the chain is passed to the end of the locking tip 2' so as to lift the locking tip 2* in such a manner that a gap is formed between the locking bow 2 and the tip 2', the gap being such that the connection ring 6 of the chain can be displaced via the tip 2• of the locking bow 2 to the opposite side, whereby the lock¬ ing bow 2 remains within the connection ring 6 up to the first locking stage. In Figure lb, the connection ring 6 of the chain is displaced between the locking bow 2 and the tip 2' thereof after the lifting of the locking bow 2, whereby half of the displacement is completed, requiring merely a slight push in the sideward direc¬ tion. In Figure 2, the locking bow 2 is locked within the inner space of the connection ring 6, whereafter the second locking stage is completed. In Figure 2a, the connection ring 6 of the chain is displaced through the T-shaped opening of the locking flap 1 above it and turned into a transverse position relative to the longitudinal axis of the lock. During the displacement, the locking flap can be pressed lightly down, whereby the displacement can be carried out without any hindrance. When the locking flap is kept in the down-pressed position, the connec¬ tion ring can be freely displaced to the final locking point. In Figures 3 and 3a, the safety lock is shown after the completion of the locking procedure in a side and top view, respectively, at which stage the safety lock is in the initial position. In order to release the connection ring of the chain from the locking position, the same measures have to be carried out as when effecting the locking, though in reverse order. The lock cannot open by it¬ self. This is prevented both by the locking flap 1 and the locking tip 2' and the way in which these opera¬ tions are carried out both during locking and un¬ locking. Figure 3b illustrates the function of the shape of the T opening of the locking flap 1. The widened opening corresponds to the locking tip 2' in width, which is required at the manufacturing stage in order that the locking tip could be passed through the T- shaped opening of the locking flap into the inner space of the lock. The narrow portion of the T-shaped opening prevents the locking tip 2' from being passed through the locking flap 1 during a strong wrench exerted on the lock. Figure 3c shows a cross-sectional view along the line a-a. It appears from the figure that the width of the tip 2' of the locking bow 2 relative to that of the T-shaped opening of the locking flap 1 is such that the locking tip 2' cannot pass out of the locking flap 1 without breaking the lock. It further appears that the locking tip 2' widens in an arched manner, so that the locking tip 2' of the locking bow 2 is forced to the centre of the T-shaped opening of the locking flap 1 so that no kind of sideward turning of the locking bow 2 is possible. Furthermore, it can be seen from the figure that the tip 2' of the locking bow 2 is round, which is required for the successful completion of the operational stage of Figure lb. The connection procedure of the connection lock shown in Figures 4, 4a, 4b, and 4, takes place in two stages. The connection lock can be attached to the safety lock already at the manufacturing stage at the broader locking end 7 thereof. In Figure 4, the con¬ nection lock is in the initial state, whereby both locking ends are positioned in an open position for the connection. In Figure 4a, the connection lock is attached to the safety lock by pressing the lock housing tip 7' against the body into a closed position, at which stage the locking tip 8* still remains in the open po¬ sition. In Figure 4b, a chain is attached to the por¬ tion 8 of the connection lock, whereafter the locking tip 8' is pressed into the lock housing 7', at which stage both lock housings are simultaneously locked into the safety position due to the shaping by bending and the flexibility. Figure 4c shows a top view of the connection lock at its final locking stage. Being broader and more resistant to wear, the portion 7 of the connec¬ tion lock is attached to the safety lock while the chain is attached to the narrower portion 8. This shape of the connection lock is mainly determined by practical needs.

Claims: Claims : 1. A safety lock intended for use in jewel and ornament chains and for purposes in which the locking effect of the lock should be especially reliable, the lock being manufactured of a flexible precious metal or other metal material resistant to shaping by bend¬ ing with various techniques in such a way that the safety lock is structurally integral and comprises a locking flap (1), a locking bow (2) and a flexible ring (3), c h a r a c t e r i z e d in that the flex¬ ible ring (3) comprises the flexibly yielding locking flap (1), which is provided with a T-shaped opening, the rather broad shape of the locking flap being de¬ termined by the width of the T-shaped opening of the locking flap (1), the width of the T-shaped opening being determined partly at the manufacturing stage by the width of the locking tip (2' ) when the locking bow (2) is bent so as to be passed within the locking flap (1) and partly by the space required by a connection ring (6) of the chain when it is being passed through the T-shaped opening of the locking flap (1) into the inner space of the safety lock; and the locking bow (2) , which is so shaped that the tip portion (2 • ) widens in an arched manner into a droplike silhouette shape, being outwardly curved at the tip thereof, and the locking bow (2) is bent so that said widened tip portion (2') of the locking bow (2) is in a closed po¬ sition near to the inner surface of the locking bow (2), which goes through the T-shaped opening of the locking flap in an arched manner, and adjacent to the T-shaped opening inside the safety lock, and that the first stage of the connection locking is carried out in such a manner that the connection ring (6) of the chain is positioned behind the widened portion of the tip (2*) of the locking bow (2), whereafter the con¬ nection ring (6) is pulled and displaced past the tip (2') in such a manner that the locking bow (2) is locked within the inner space when the lifted locking tip (2') returns to the closed position, whereafter at the second stage by pressing down the locking flap (1) , the connection ring (6) can be freely displaced out through the T-shaped opening into the final lock¬ ing position, whereby the locking reliability so obtained is such that the same steps as at the locking stage in reverse order are required for unlocking. 2. A safety lock according to claim 1, com¬ prising a connection lock (7, 8) to be attached to the safety lock already at the manufacturing stage, the lock being manufactured of a flexible precious metal or other metal mineral or other material resistant to shaping by bending and tensile stress with various techniques in such a way that the structurally inte¬ gral lock (7, 8) comprises a connection housing (7) for connection to the flexible ring (3) and a con¬ nection housing (8) for connection to the chain, c h a r a c t e r i z e d in that the connection housing (7) positioned at one end of the body and pro¬ vided with a lock housing (7') at the tip of the body thereof is fastened by pressing the tip portion (7') of the lock (7, 8) against the body of the lock (7, 8) after the connection, whereby the first connection housing (7) is formed, while the chain connection housing (8) of the connection lock (7, 8) remains in the open position, which connection housing (8) is pressed to the closed position after having been attached to the chain, whereby the second housing (8) is formed when both housings of the lock are passed to the safety locking position simultaneously, by which measure the locking reliability of the lock equals to that of the safety lock, and the lock (7, 8) unlocks only by releasing the locking tip (8' ) from the lock housing (7*) by means of a lifting movement.

Inventors: RANTA OLAVI A, RANTA, OLAVI, A.
Applicants: RANTA OLAVI A, RANTA, OLAVI, A.
Application year: 1989
Main classification: A44C11
IPC codes: A44C5, A44C25, F16B45