EP2536903B1

EP2536903B1 - Break-in resistant lock

Info

Publication number: EP2536903B1
Application number: EP10711736.8A
Authority: EP
Inventors: Marco Loli; Fausto Fustini
Original assignee: CISA SpA
Current assignee: CISA SpA
Priority date: 2010-02-18
Filing date: 2010-02-18
Publication date: 2014-06-04
Anticipated expiration: 2030-02-18
Also published as: WO2011101877A8; EP2536903A1; EA201290805A1; WO2011101877A1; EA027077B1

Description

Technical field

The present invention relates to a break-in resistant lock adapted to hinder any attempt at forcing, in particular a lock of the type adapted to be operated with a double-web key.

Background art

Locks associated with double-web keys are constituted by a main box-like body which is provided with a (substantially transverse) seat that is adapted for insertion of the key.
The key, once inserted, is arranged so that its combination-bearing portion is aligned with a plurality of combination plates (normally known as tumblers), which can perform a partial translational motion along preset directions.
The rotation of the key in the seat entails a movement of the plates (tumblers), which is matched by the disengagement of a rod (which is normally engaged by interference on the plates): such rod can thus be moved with a translational motion by the rotary motion of the key in the seat.
The bolts are stably coupled on the front portion of the rod: the translational motion of the rod entails the exit of the bolts from the front edge of the lock, with consequent stable engagement thereof in the receptacles of the jamb, to ensure correct closure of the door in which the lock is installed.
This type of lock ensures a good level of protection against break-in attempts of a destructive type, since the generous size allows to provide embodiments of the armored type.
More specifically, specific types are known for these locks which provide for the possibility to change the combination that corresponds to the key required for opening.
If the keys are lost or if it is necessary to give them temporarily to the people of unconfirmed trustworthiness, it is possible to change the combination of the lock in order to associate it with a new key.
Key changing can be performed simply, without disassembling the lock or parts thereof, and an unlimited number of times.
The double-web key operates respective combination plates, each of which is constituted by a lamina and by a respective complementary lamina, which mate with each other stably: the rotation of the key causes the exit or retraction of the bolts associated with the plates.
During combination changing, by using a suitable tool on an internal lever system, it is possible to apply a force to the complementary laminas in order to disconnect them from the respective laminas. The subsequent mating of each lamina with the respective complementary lamina is possible by adopting, as an element adapted to define their mutual position, a new key with a different combination: in this manner, the lock assumes the combination of such key.
However, it is possible to access the internal lever system, although this is a complex and difficult activity, with specific forcing tools, through the key access hole, in order to move it into the position that disconnects the laminas from the respective complementary laminas: in this position it is simple to move the lock to the open configuration because it is possible to adopt any key to "recode" the lock.
This possibility of break-in is a severe problem for this type of lock.
Locks with changeable codes are known, for example, from documents EP 0 943 761 A1 and DE 20 2007 016 675 U1 , wherein EP 0 943 761 A1 discloses a lock according to the preamble of claim 1.

Disclosure of the invention

The aim of the present invention is to solve the above-mentioned drawbacks, by providing a break-in resistant lock in which it is not possible to operate the lever systems by accessing from the keyhole with forcing tools.
Within this aim, an object of the present invention is to provide a break-in resistant lock that has low costs, is relatively simple to provide in practice and is safe in application.
This aim and this object, as well as others which will become better apparent hereinafter, are achieved by a break-in resistant lock, according to the present invention, that has the features set forth in claim 1.

Brief description of the drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of the break-in resistant lock according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a sectional perspective view of a portion of a break-in resistant lock according to the invention;
Figure 2 is a sectional perspective view of the portion of the break-in resistant lock of Figure 1 during preparation for combination changing;
Figure 3 is a sectional side view of a detail of the lever system for actuating the setting of a new combination of a break-in resistant lock according to the invention in the inactive configuration, while a break-in attempt consisting in lifting a contoured arm is in progress;
Figure 4 is a sectional side view of the detail of the lever system for actuating the setting of a new combination of a break-in resistant lock according to the invention in the active configuration.

Ways of carrying out the invention

With reference to the figures, the reference numeral 1 generally designates a break-in resistant lock.
The lock 1 comprises a box-like containment body 2, which is provided with openings 3 along at least one of its perimetric faces. As a first approximation, it can be noted that the box-like body 2 is shaped like a transversely flattened parallelepiped: the two larger faces are mutually opposite and mutually coupled by means of the perimetric edge.
Such perimetric edge provides the openings 3, which are designed for the passage of at least one spring-latch and at least one bolt; the bolt is actuated by means of a respective translating band (normally referenced as rod and/or bolt movement element).
The translating band in turn is actuated translationally by means of the rotations of at least one key; in particular, the rotations of the at least one key are dependent upon movement into the disengagement configuration, with respect to an adapted fixed pivot (also known as square pivot as a consequence of its cross-section, which is normally square) on the translating band, of a plurality of plates with a combination.
The combination plates are provided with a portion that interferes with the stroke of the key during rotation: such interfering portion is contoured so that when the key is arranged transversely with respect to the keyhole for insertion in the lock 1 the plates lifted by the key (since the interfering portions rest on respective areas of the combination of the key) are appropriately aligned in order to allow the pivot to perform a translational motion along a convenient trajectory identified by the slots of the juxtaposed plates.
Each combination plate is constituted by a lamina and a complementary lamina, which are mutually mated and can be uncoupled by means of a lever system 4 which is actuated with a tool 5 from the outside through a respective hole 6 provided in the perimetric edge of the box-like body 2.
The lever system 4, according to a preferred embodiment, is constituted by two functionally associated elements; it in fact comprises a translating rod 7 and a contoured arm 8, which can rotate with respect to a pivoting axis 9.
The rod 7, in order to ensure correct operation of the lock 1 according to the principles of allowing the setting of a new combination for its plates, can move from a first inactive configuration, in which one of its edges 10 is substantially aligned with and proximate to a portion 11 of the arm 8, preventing its rotation, to a second enabling configuration, in which, by means of the tool 5 (which in turn is inserted in the hole 6 to apply an axial compression of the rod 7), one end 12 of the rod 7 rests on a tab 13 of the arm 8. The tab 13 is substantially eccentric with respect to the axis 9; in this second configuration the arm 8 is rotated through a predefined angle and interferes, by means of its end stem 14, with the complementary laminas for their uncoupling from the respective laminas (the uncoupling allows to change the mutual position of laminas and complementary laminas, with consequent new combination of the lock 1, i.e., the possibility to be opened by using a key other of the one used prior to uncoupling).
Inside the body 2, between the arm 8 and an opening 15, that is generally known as keyhole, for the insertion of the key, a contoured block 16 is interposed to block at least partially the passage inside the body 2 between the opening 15 and the arm 8.
The presence of the contoured block 16 hinders any break-in actions performed by inserting forcing tools in the opening 15 to grip the arm 8 and move it until the laminas are disengaged from the respective complementary laminas.
According to particular embodiment of unquestionable interest in practice and in application, the rod 7 has, proximate to its end 12, a recess 17 which is adjacent to the edge 10.
The recess 17 can be constituted by an actual hollow seat or by a simple notch obtained by machining with removal of material from the rod 7.
In particular, in the accompanying figures there is a recess 17 which has a substantially circular contour whose maximum depth is substantially less than half the thickness of the rod 7.
According the invention, the portion 11 of the arm 8 can be constituted by a protruding beak which is directed, in the assembled configuration, toward the end edge 10 of the rod 7.
In this case, the protruding beak, when the lock 1 is in the first configuration described earlier, is arranged so as to rest on the edge 10, consequently locking the rotations of the arm 8 jointly connected thereto.
When the lock 1 is in the second configuration, the protruding beak faces the recess 17, as a consequence of a translational motion of the rod 7 toward the tab 13 of the arm 8.
At this point a further translational motion of the rod 7 causes a rotation of the arm 8, which is allowed as a consequence of the free stroke of the protruding beak toward the bottom of the recess 17.
Analyzing specifically the arm 8, it is noted that such arm preferably has a pivoting hollow at the axis 9, such hollow being arranged on a band 18 which is axially offset with respect to a central portion 19 of the arm 8.
The central portion 19 has the tab 13 at its region for connection to the band 18.
In turn, the central portion 19 has an end wing 20, at the stem 14, which, when the lock 1 is in the first previously described configuration, rests with its lower surface on a reference block 21 and, when the lock 1 is in the second configuration, rests with its upper surface against an abutment pin 22.
The reference block 21 and the abutment pin 22 are jointly connected to the body 2 and constitute the lower limit and the upper limit of the rotation of the arm 8.
It is appropriate to note that in order to avoid tampering of the lock 1 by using tools that are simple to obtain, such as screwdrivers or center punches, the hole 6 and the tool 5 have complementary and conjugate profiles: only a tool 5 with a suitable profile can therefore be inserted in the hole 6 and therefore only a specific tool 5 can be used to start a change of the combination of the lock 1.
Advantageously, the break-in resistant lock 1 according to the invention does not allow the possibility to actuate the lever systems 4 by accessing from the window or keyhole 15 with forcing tools.
Conveniently, the break-in resistant lock 1 according to the invention has low costs, is relatively simple to provide in practice and is safe in application.
In the exemplary embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.
In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

A break-in resistant lock of the type that comprises a box-like containment body (2) provided with openings (3) along one of its perimetric faces for the passage of at least one spring-latch and at least one bolt, said bolt being actuated by means of a respective band that performs a translational motion and in turn is actuated to perform a translational motion by means of the rotations of at least one key, the rotations of said at least one key being dependent upon the movement into the disengagement configuration, with respect to an adapted fixed pivot on the band, of a plurality of combination plates, each constituted by a lamina and a complementary lamina which are mutually mated and can be uncoupled by means of a lever system (4) which is operated with a tool (5) from outside through a respective hole (6), wherein said lever system (4) comprises a translating rod (7) and a contoured arm (8) which can rotate with respect to a pivoting axis (9), said rod (7) being movable from a first inactive configuration, in which one of its edges (10) is substantially aligned with and proximate to a portion (11) of the arm (8), to a second enabling configuration, in which, by means of said tool (5) inserted in the hole (6) in axial compression of said rod (7), an end (12) of said rod (7) rests on a tab (13) of the arm (8), which is substantially eccentric with respect to the axis (9), in said second configuration said arm (8) being turned through a predefined angle and interfering, by means of its end stem (14), with said complementary laminas for the uncoupling of said complementary laminas from the respective laminas, characterized in that said translating rod (7), in said first inactive configuration in which one of its edges (10) that is substantially aligned with and proximate to a portion (11) of the arm (8), prevents rotation of said contoured arm (8).
The break-in resistant lock according to claim 1, characterized in that within said body (2), between said arm (8) and the opening (15) for inserting said key, a contoured block (16) is interposed in order to obstruct at least partially the passage inside the body (2) between the opening (15) and the arm (8).
The break-in resistant lock according to claim 1, characterized in that said rod (7) has, proximate to its end (12), a recess (17) that is adjacent to said edge (10).
The break-in resistant lock according to claim 1, characterized in that said portion (11) of said arm (8) is constituted by a protruding beak which is directed, in the assembly configuration, toward said end edge (10) of said rod (7).
The break-in resistant lock according to claims 3 and 4, characterized in that said protruding beak in said first configuration is arranged so as to rest on the edge (10), with consequent locking of the rotations of the arm (8) jointly connected thereto, and in said second configuration faces the recess (17), as a consequence of a translational motion of said rod (7) toward the tab (13) of the arm (8), a further translational motion of the rod (7) causing a rotation of the arm (8), which is allowed as a consequence of the free stroke of the protruding beak toward the bottom of the recess (17).
The break-in resistant lock according to claim 1, characterized in that said arm (8) has a pivoting hollow at the axis (9), said hollow being arranged on a band (18) which is axially offset with respect to a central portion (19) of said arm (8), said central portion (19) having said tab (13) at its region for connection to said band (18).
The break-in resistant lock according to one or more of the preceding claims, characterized in that said central portion (19) has an end wing (20), at said stem (14), which in said first configuration rests with its lower surface on a reference block (21) and, in said second configuration, rests with its upper surface on an abutment pin (22), said reference block (21) and said abutment pin (22) being jointly connected to said body (2).
The break-in resistant lock according to one or more of the preceding claims, characterized in that said hole (6) and said tool (5) have conjugate and complementary profiles.