The present invention relates to a break-in resistant lock cylinder for a cylinder lock and to an associated key.

The lock cylinder constitutes the principal active component of a, lock: it is constituted by a stator which is integral with the lock and inside which a rotor is selectively rotatable. The rotor is provided with an opening for the insertion of a coded key: interposed between the rotor and the stator are adapted pins of predefined length, which are kept elastically in a position of interference between the rotor and the stator. The coding pattern of the key enables the alignment of the end edge of each pin with the surface for interfacing between the stator and the rotor, with consequent freedom of the rotor to rotate with respect to the stator.

The coding pattern of the key consists of the provision of a contoured profile thereof which is provided with a pattern such that, once the key is completely inserted in the opening of the respective rotor, each pin, pushed by a respective portion of the contoured profile of the key in contrast with the elastic means, has its edge aligned with the interface surface between rotor and stator.

Among cylinder locks, much interest is shown in locks that have a seat for accommodating the key which is substantially flat (as is therefore also the associated key), with the pins, which detect the key, operating in a direction that is substantially transverse with respect to the seat (therefore acting on flat portions of the key).

Such locks are usually identified by the type of key associated with them, and are called "flat key locks".

The risk of forcing the lock is guarded against with complex encoding of both lock and key: particular break-in techniques make it possible to actuate the pins in order to open the lock, even in the absence of the original key. Given the small dimensions of a lock of the type in question it is not substantially possible to increase the number of pins in order to ensure greater security against forcing. As with any lock, furthermore, it is necessary to guard against break-in actions, carried out with lockpicks, the goal of which is to lower the pins in sequence thus making it possible to free the rotor with respect to the stator and, therefore, to open the lock.

The principal aim of the present invention is to solve the above mentioned drawbacks, by providing a break-in resistant lock cylinder for a cylinder lock which is particularly secure against break-in attacks and lock- picking.

Within this aim, an object of the invention is to provide a break-in resistant lock cylinder with a simple structure and a high level of security.

Another object of the invention is to provide a key for break-in resistant lock cylinders which increases the level of security of the cylinders with which it is mated.

Another object of the invention is to provide a break-in resistant lock cylinder and a key for break-in resistant lock cylinders which have a structure and a geometry which are alternative and different with respect to conventional ones.

Another object of the present invention is to provide a break-in resistant lock cylinder and an associated key that are low cost, easily and practically implemented, and safe in use.

This aim and these and other objects which will become better apparent hereinafter are achieved by a break-in resistant lock cylinder for a cylinder lock, of the type comprising a stator which is provided with a substantially cylindrical accommodation for a rotor, said rotor and said stator being affected by at least one channel for at least one respective pin, which is slideably moveable inside it, the arrangement, for locking, of said at least one pin partly in said rotor and partly in said stator resulting in the immobilization of said rotor, the arrangement, for opening, with the alignment of an end edge of said at least one pin with the interface surface between stator and rotor, which is obtained by way of the insertion of an adapted key with a contoured profile into an opening of the rotor facing onto the at least one channel, resulting in the free rotation of said rotor with respect to said stator, characterized in that said at least one pin comprises an ogive which is provided with a contoured cavity and a peg which is provided with two mutually opposite protruding appendages and with a central rim acting as an abutment shoulder, said at least one channel of said rotor comprising a first section with a substantially larger diameter than the diameter of said central rim and a second section with a substantially smaller diameter than the diameter of said central rim and larger than the diameter of a first protruding appendage, the front of said first protruding appendage, upon the insertion of said key into said opening of said rotor, being accommodated in a respective profiled groove, which has different depths at different longitudinal sections of said key, with consequent substantially complete insertion of the second protruding appendage into the cavity of said ogive according to said open arrangement.

This aim and these and other objects are also achieved by a key for break-in resistant lock cylinders which is characterized in that it comprises, on at least one flat surface thereof, at least one profiled groove, which has different depths at different longitudinal sections of said key, the groove being arranged between the end tip of the key and the region thereof which is intended for alignment with the front surface of the respective lock cylinder, when said key is inserted therein.

This aim and these and other objects are also achieved by a lock constituted by a break-in resistant lock cylinder and a respective key, said lock cylinder being of the type comprising a stator which is provided with a substantially cylindrical accommodation for a rotor, said rotor and said stator being affected by at least one channel for at least one respective pin, which is slideably moveable inside it, the arrangement, for locking, of said at least one pin partly in said rotor and partly in said stator resulting in the immobilization of said rotor, the arrangement, for opening, with the alignment of an end edge of said at least one pin with the interface surface between stator and rotor, which is obtained by way of the insertion of an adapted key with a contoured profile into an opening of the rotor facing onto the at least one channel, resulting in the free rotation of said rotor with respect to said stator, characterized in that said at least one pin comprises an ogive which is provided with a contoured cavity and a peg which is provided with two mutually opposite protruding appendages and with a central rim acting as an abutment shoulder, said at least one channel of said rotor comprising a first section with a substantially larger diameter than the diameter of said central rim and a second section with a substantially smaller diameter than the diameter of said central rim and larger than the diameter of a first protruding appendage, said respective key comprising, on at least one flat surface thereof, at least one profiled groove, which has different depths at different longitudinal sections of said key, the groove being arranged between the end tip of the key and the region thereof which is intended for alignment with the front surface of the respective lock cylinder, when said key is inserted therein, the front of said first protruding appendage, upon the insertion of said key into said opening of said rotor, being accommodated in said profiled groove, with consequent substantially complete insertion of the second protruding appendage into the cavity of said ogive according to said open arrangement.

Further characteristics and advantages of the invention will become better apparent from the description of some preferred, but not exclusive, embodiments of the break-in resistant lock cylinder and of the associated key, according to the invention, which are illustrated by way of non-limiting examples in the accompanying drawings wherein:

Figure 1 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of a first embodiment of a break-in resistant lock cylinder and an associated key, according to the invention in a first configuration;

Figure 2 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of the break-in resistant lock cylinder and the associated key in Figure 1 , in a second configuration;

Figure 3 is a view from above of a possible embodiment of a key according to the invention;

Figure 4 is a side view of the key in Figure 3 ;

Figure 5 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of a second embodiment of a break-in resistant lock cylinder and an associated key, according to the invention in a first configuration;

Figure 6 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of the break-in resistant lock cylinder and the associated key in Figure 5, in a second configuration;

Figure 7 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of the break-in resistant lock cylinder and the associated key in Figure 5, in a third configuration;

Figure 8 is a cross-sectional view, taken along a plane that is perpendicular to the axis of the rotor of the cylinder, of the break-in resistant lock cylinder and the associated key in Figure 5, in a fourth configuration;

Figure 9 is a view from above of a further embodiment of a key according to the invention;

Figure 10 is a side view of the key in Figure 9.

With particular reference to the figures, the reference numeral 1 generally designates a break-in resistant lock cylinder for a cylinder lock, and the reference numeral 2 generally designates an associated key.

The break-in resistant lock cylinder 1 comprises a stator 3 which is provided with a substantially cylindrical seat 4 for a respective rotor 5.

The rotor 5 and the stator 3 are affected by at least one channel 6 (which is parallel to the longitudinal axis of the rotor 5) for at least one respective pin 7, which is slideably moveable inside the channel 6.

The pin 7 is arranged in a locked configuration when it is partially accommodated in the rotor 5 and partially accommodated in the stator 3, thus resulting in the immobilization of the rotor 5.

The pin 7 is arranged in an open configuration when the alignment occurs of an end edge 8 of the at least one pin 7 with the interface surface between the stator 3 and the rotor 5, which is obtained by way of the insertion of the adapted key 2 with a contoured profile into an opening 9 of the rotor 5 facing onto the at least one channel 6, thus producing the free rotation of the rotor 5 with respect to the stator 3.

The at least one pin 7 comprises an ogive 10 which is provided with a contoured cavity 11 and a peg 12 which is provided with two mutually opposite protruding appendages 13 and 14, and with a central rim 15 acting as an abutment shoulder.

The at least one channel 6 of the rotor 5 comprises a first section with a substantially larger diameter than the diameter of the central rim 15 and a second section with a substantially smaller diameter than the diameter of such central rim 15 and larger than the diameter of a first protruding appendage 13.

The front of the first protruding appendage 13, upon the insertion of the respective key 2 in the opening 9 of the rotor 5, is accommodated in a respective profiled groove 18 of this key 2.

The profiled groove 18 has different depths at different longitudinal sections of the key 2.

It should be noted that the variation of the depth of the groove 18 is provided continuously, with a joined and continuous surface so that the first protruding appendage 13 of the pin 7 can slide easily thereon (during the insertion of the key 2 in the opening 9) without the possibility of phenomena of sticking arising. The possibility is not excluded of adopting grooves 18 in which the depth varies according to mutually connected consecutive flat portions: this second possibility may be simpler in terms of practical implementation.

When the key 2 is completely inserted in the opening 9, the substantially complete insertion occurs of the second protruding appendage 14 in the cavity 11 of the ogive 10 according to the configuration of the pin 7, which permits the opening of the lock cylinder 1.

In this first case the groove 18 will be linear and will have a direction of extension substantially parallel to the longitudinal axis of the key 2.

According to a particular embodiment of undoubted practical and applicative interest, it should further be noted that the central rim 15 acting as an abutment shoulder can comprise, in turn, a substantially spherical lower portion which has a maximum diameter 16 which is not less than the maximum diameter of the rim 15.

It should be noted that the hemispherical lower portion can have a maximum diameter 16 which at most coincides with the diameter of the rim 15 : in such case such spherical lower portion can have its top coinciding and perfectly joined with the rim 15, to the extent that it is not possible to distinguish the rim 15 from the upper face of the hemispherical portion.

In such case the at least one channel 6 of the rotor 5 will comprise a first section with a substantially larger diameter than the diameter of the central rim 15 and of its spherical lower portion (the maximum diameter 16 of which was defined previously) and a second section which will have a diameter comprised substantially between the diameter of the central rim 15 (including its spherical lower portion) and the diameter of a first protruding appendage 13.

It should be noted that, in any case, conveniently elastic means 19 are interposed between the ogive 10 and the peg 12 for mutually spacing apart.

The presence of the elastic means 19 will therefore have the goal of keeping under elastic force the at least one pin 7 in the preset locked configuration of the cylinder 1 ^* , in the absence of a key 2 inside the opening 9.

The contoured cavity 1 1 is shaped so as to define a seat of greater extent, which is defined starting from its edge facing toward and proximate to the peg 12 up until a point proximate to its midpoint, and a pit with a diameter slightly larger than that of the second appendage 14 of the peg 12, arranged downstream of the seat of greater extent.

This shape structure will make it possible to trap the second appendage 14 of the peg 12 upon attempts at opening executed without using the key 2 (therefore upon break-in attempts).

It should be noted that the seat of greater extent and the pit of the contoured cavity 1 1 are arranged in a mutual position which is chosen from among concentricity, parallelism without alignment, and completely skewed. In this manner it is possible to provide specific forms of encoding in which the peg 12 has a different orientation with respect to the ogive 10 (i.e. that the axis of the peg 12 and the axis of the ogive 10 are mutually inclined at the correct open arrangement, or that the peg 12 can be trapped in the contouring of the ogive 10 when inclined in directions other than the direction that would be imposed by the groove 18 of the key 2).

According to a particularly advantageous embodiment from an implementation point of view, the portion 3a, of the stator 3, of the at least one channel 6 can preferably be constituted by a recess, which is delimited by inclined planes which join with the inner walls of the cylindrical accommodation 4.

In such case, the ogive 10 will comprise a tapered end tip with an axial symmetry (for example frustum-shaped, ellipsoidal, spherical etc.) which is adapted to slide on the inclined planes, during the rotation of the rotor 5 with respect to the stator 3.

According to an embodiment of undoubted practical and applicative interest which offers high levels of security against forcing, the pins 7 can be a plurality, and are substantially aligned along the opening 9 of the rotor 5.

In such case the pegs 12 of the pins 7 will be differently shaped for the insertion of the respective first appendages 13 in the profiled groove 18 of the key 2 and for the accommodation of a respective second appendage 14 in a respective pit of a respective ogive 10.

Having a plurality of pins 7 makes it possible to execute a more complex encoding of the key 2, by taking advantage of the variations in depth and direction of the groove 18.

The fact that the groove 18 varies its depth continuously, without defining steps, allows the first appendages 13 to easily slide along them without risk of jamming, and it enables a potentially infinite number of forms of encoding.

In fact any depth value of the groove 18 can be provided, just as it is possible to take advantage of the inclination of the bottom surface of the groove on which the front of each appendage 13 will rest: this means that pegs 12 can be designed for a specific and well-defmed depth of the groove 18 (at the cross-section thereof on which the corresponding appendage 13 lies) and/or for a specific and well-defmed inclination thereof (with which the front of the respective appendage 13 will have to suitably mate).

It should be noted that, with regard to an embodiment which is intended to further increase the level of security offered against forcing, the rotor 5 and the stator 3 comprise at least one further through hole, which is substantially opposite the channel 6 and is aligned with a second profiled groove of the key 2, for the slideable accommodation of at least one respective tumbler which is moveable.

Such tumbler is movable between a locked configuration, in which it is interposed between the rotor 5 and the stator 3, and an open configuration, in which it has an end thereof inserted in the second groove and is completely contained in the rotor 5. The presence of two elements for reading the grooves 18 present on the key (the pin 7 and the moveable tumbler) makes it possible to substantially increase the level of security against forcing.

It should be noted that the present invention also relates to a key 2 for break-in resistant lock cylinders 1 which comprises, on at least one flat surface 20 thereof, at least one profiled groove 18, which has different depths at different longitudinal sections of the key 2.

The groove 18 is arranged between the end tip 21 of the key 2 and the region 22 thereof which is intended, when the key 2 is in the configuration of insertion in the respective lock cylinder 1, to be aligned with the front surface of the lock cylinder 1.

The groove 18 will have a linear progression and can be parallel to the longitudinal axis of the key or inclined with respect thereto.

It is essential to note that, according to a particularly advantageous embodiment in terms of increasing the number of possible forms of coding that can be provided, the at least one profiled groove 18, which has different depths at different longitudinal sections of the key 2, has a substantially variable direction.

The variation of the direction can occur as a sequence of consecutive mutually inclined straight portions which are mutually connected, or as a curved line with only one concavity or with one or more consecutive bends.

It should be noted that, if it is desired to provide a key 2 that has extremely high levels of security and therefore is adapted to cooperate with a particularly secure lock cylinder 1 , the grooves 18 can be at least two in number, arranged on flat surfaces 20 which are symmetrically mutually opposite with respect to the central longitudinal axis of the key 2.

The present invention defines the protection for a break-in resistant lock which is constituted by a break-in resistant lock cylinder 1 and by a respective key 2.

The lock cylinder 1 will be of the type comprising a stator 3 which is provided with a substantially cylindrical accommodation 4 for a rotor 5.

The rotor 5 and the stator 3 will be affected by at least one channel 6 for at least one respective pin 7, which is slideably moveable inside it.

The arrangement, for locking, of partial accommodation of the at least one pin 7 in the rotor 5 and in the stator 3 results in the immobilization of the rotor 5, with consequent stable closing of the lock (and therefore of the lock cylinder I).

The arrangement for opening, which corresponds to the alignment of an end edge 8 of the at least one pin 7 with the interface surface between the stator 3 and the rotor 5, which is obtained by way of the insertion of the adapted key 2, with a contoured profile, into an opening 9 of the rotor 5 facing onto the at least one channel 6, produces the free rotation of the rotor 5 with respect to the stator 3.

According to the invention, the at least one pin 7 comprises an ogive 10 which is provided with a contoured cavity 1 1 and a peg 12 which is provided with two mutually opposite protruding appendages 13, 14 and with a central rim 15 acting as an abutment shoulder.

Such at least one channel 6 of the rotor 5 comprises, in turn, a first section with a substantially larger diameter than the diameter of the central rim 15 and a second section with a substantially smaller diameter than the diameter of this central rim 15 and larger than the diameter of the first protruding appendage 13.

The respective key 2, in turn, comprises, on at least one flat surface 20 thereof, at least one profiled groove 18, which has different depths at different longitudinal sections of the key 2.

The groove 18 is arranged between the end tip 21 of the key 2 and the region 22 thereof which is intended to be aligned with the front surface of the respective lock cylinder 1.

When the key 2 is inserted in the channel 6, the front of the first protruding appendage 13 is inserted in the groove 18. This will produce the consequent substantially complete insertion of the second protruding appendage 14 in the cavity 11 of the ogive 10 according to the open arrangement.

In such lock according to the invention, the central rim 15 acting as an abutment shoulder can comprise a substantially spherical lower portion with a maximum diameter 16 which is not less than the maximum diameter of the rim 15.

The at least one channel 6 of the rotor 5 in such case will comprise a first section with a substantially larger diameter than the diameter of the central rim 15 and of its spherical lower portion.

The channel 6 will further comprise a second section with a substantially smaller diameter than the diameter of the central rim 15 and of its spherical lower portion, and larger than the diameter of a first protruding appendage 13.

In such case the at least one profiled groove 18 will have different depths at different longitudinal sections of the key 2 and will also have a substantially variable direction.

Advantageously the present invention solves the above mentioned problems, by providing a break-in resistant lock cylinder 1 for a cylinder lock which is particularly secure against break-in attacks and lock-picking, by dint of the adoption of pins 7 which are constituted by an ogive 10 and a peg 1 1 (which is intended to be partially accommodated in a contoured cavity 1 1 of such ogive 10): the second appendage 14 of the peg 12 and the cavity 1 1 of the ogive 10 are shaped complementarily so as to be able to mate only following a specific geometric alignment as a consequence of a specific height of the peg 12 (such height is controlled by the particular depth of the groove 18 of the key 2).

If the groove 18 also comprises variations of its direction, the second appendage 14 of the peg 12 and the cavity 11 of the ogive 10 will be able to mate only following a specific geometric alignment as a consequence of a specific height and of a specific angular arrangement of the peg 12 (such angular arrangement is controlled by the particular shape structure of the groove 18 of the key 2).

The fact that the depth of the groove 18 can vary continuously offers the possibility of providing different forms of encoding according to a potentially infinite number of combinations, by dint of the infinite heights at which the peg 12 can be arranged in the correct open configuration.

If the variation of the depth of the groove 18, with the continuous possibilities this offers, is then combined with the fact that its direction can also vary, with the continuous possibilities this offers (thus creating tortuous and twisting patterns), it can be seen that the lock cylinder 1 according to the invention, the key 2 according to the invention and the lock that comprises them, all result in a considerable technical progress in the sector of locks, by offering extremely high levels of security, without requiring the presence on the key 2 of moveable elements, which constitute a criticality during the manufacturing step (in that they are complex and costly) and they are also delicate (they can be damaged with impacts and/or drops).

Effectively the break-in resistant lock cylinder 1 for a cylinder lock simultaneously offers a simple structure and a high level of security.

Positively the key 2 for break-in resistant lock cylinders 1 is therefore adapted to increase the level of security of the lock cylinders 1 with which it is mated.

Positively the break-in resistant lock cylinder 1 and the respective key 2 (as well as the lock constituted by the two) according to the invention have a structure and a geometry which are alternative and different with respect to conventional ones.

The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements. For example the ogive 10 can be constituted by an elongated shell (of the type of an at least partially concave bar or rod) which is provided with a plurality of internal seats which define, taken together, a specific contoured cavity 11.

Each seat would be designed to accommodate a corresponding second protruding appendage 14 of a respective peg 12.

In such case, only the condition in which all the pegs 12 are accommodated in the respective seats (they therefore being contained overall in the cavity 11 that the seats constitute) can result in the opening of the lock cylinder 1.

In the embodiments illustrated, individual characteristics shown in relation to specific examples may in reality be interchanged with other, different characteristics, existing in other embodiments.

In practice, the materials employed, as well as the dimensions, may be any according to requirements and to the state of the art.

Where the technical features mentioned in any claim are followed by reference numerals and/or signs, those reference numerals and/or signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference numerals and/or signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference numerals and/or signs.