TECHNICAL FIELD

The present invention falls into the category of accessories for locks and, more particularly, of those devices made to raise the security level of locks designed to be operated by a standard European type cylinder .

SUMMARY DESCRIPTION OF THE INVENTION

The present invention relates to a burglar-proof device for the protection and operation of locks that can be installed on all types of locks designed to be operated by a standard European type cylinder , without requiring any modification of the same locks.

This burglar-proof device consists of an outer shell whose function is to protect and contain the mechanisms, or devices, for the recognition of the key. These mechanisms can be of various types and having different operating principles and will hereinafter generically be referred to as "cylinder".

The outer shell is axially constrained to a shaft having the dual function of transmitting the rotary motion from the key to the lock as well as to be resistant against attempts aimed at forcing or extracting the outer shell, together with the whole burglar-proof device, from the lock on which the device itself is installed.

The shaft is made of high strength material and, thanks to its dual function of fastening and transmission device as described above, can occupy most of the room in the lock that in the present art is totally occupied by the standard European type cylinder.

In this way the shaft of this invention can be of such a size as to provide a mechanical strength significantly higher than the systems and components currently in use, overcoming the limitations in the present art that have and continue to compel lock producers to use other mechanical parts, placed in other parts of the lock, to fasten the cylinder to the lock in order to avoid the forced extraction of the shell and the cylinder.

The present invention does not exclude, however, that such mechanical parts, currently available in the art, can still be included in the present invention.

At the present art these mechanical parts, mostly consisting of screws or other fastening devices, cannot be built of a size big enough to guarantee a high mechanical strength since they must be placed in confined spaces with geometric and functional constraints .

Instead, the shaft of the device object of this invention in order to perform one of its dual functions, that is operating the lock , has on its outer surface a cam, rigidly attached to the shaft itself and rotating with it, the cam being of a shape and size to be able to operate the lock on which the device is mounted.

The shaft, in order to perform the other of its dual functions, that is fastening the cylinder to the lock, also has a thread on the opposite side in respect to the outer shell. Once the shaft is inserted into both the lock and the inner flange, a nut is tightened, in order to obtain the strong connection between the shell, the shaft and the lock. The device is also equipped with an anti-rotation pin located within the perimeter of the area where in the present art the standard European cylinder lock is accommodated. The anti-rotation pin has the dual function of preventing the rotation of the outer shell in respect to the lock as well as to add another fastener, represented by a screw, that is screwed to the inside end of the anti-rotation pin itself.

The burglar-proof device object of the present invention represents a significant advancement in the specific field of technology as it has a much higher resistance to being torn from the lock on which it is mounted compared to the fastening systems currently known and used in the present art .

BACKGROUND ART

At the present art the burglar-proof devices, mostly consisting of screws or other fastening elements, cannot be built of a size big enough to guarantee a high mechanical strength and, in the last few years ,they have been showing a vulnerability to attacks.

In recent years we are witnessing the spread of a burglary technique that consists in the extraction or tearing of the cylinders from their locks.

This technique is practiced mainly with screw extractors, lever pipes and other tools. These tools are simple but highly effective as they are able to download high withdrawal forces.

Technical improvements in the defense of the cylinder locks have been gradually introduced onto the market since the above burglary technique has spread. In particular steel shells have been introduced to protect the lock cylinder from physical attacks.

These steel shells, also known by the name "Defender", are anchored to the lock using various methods, mostly consisting of screws which are introduced from inside the lock and which serve to secure the protective shell of the lock itself .

Despite these improvements, such protections have proved to no longer be able to stand up to the recent burglary techniques described above for at least two reasons. One reason is the impossibility of setting the device of the type "Defender" with screws of a suitable diameter. The inability to use screws with an appropriate diameter is due both to the existence of geometric limits of the whole lock-shell, as well as the fact that in the cylinder area there are also various other mechanical parts that cannot be technically eliminated.

A second reason is identifiable in the geometric size and shape imposed by the shape of the standard European cylinder lock that does not allow the creation of cylinder locks with higher mechanical performance.

Many other technical improvements in the cylinder anti- theft protection art have been recently introduced in order to increase the mechanical strength of lock cylinders and their protective devices. Into this technological background entered the Italian Patent No. 0001377022 granted on July.S* 2010 to Mottura Serrature di Sicurezza S.p.A. The value of this invention is based on reinforcing the cylinder lock with two additional elements of reinforcement to increase the mechanical strength of the lock. This invention, however, gives poor results in terms of safety due to the small size of the reinforcement elements themselves .

With the patent application deposited in Italy with n. RM2008A000228 on April 30* 2008 by Benny System SRL, a tubular reinforcement was introduced with the purpose of protecting the shell. The practical application of the substance of this invention, however, implies the need for major modifications to both the door on which the lock is mounted and to the lock itself. The need for such significant modifications limits the effectiveness of the invention as well as its potential .market penetration.

For completeness, it is deemed important to mention the patent application deposited in Italy with n. TV2007A000195, by Oliana

Pierluigi consisting of a reinforcement and protection device for cylinder locks.

The device disclosed in the above invention has the limitation of having to be fixed to the lock with two screws of a reduced size, due to the limited space available, and can therefore be easily overcome with simple tools used in burglaries.

Notwithstanding the above mentioned technological progress in this field, the current market demands a more sophisticated and secure burglar-proof devices for the protection and operation of security locks. DISCLOSURE OF THE INVENTION AND DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides a unique burglar-proof device which offers a technical solution to market demand for high security.

The present invention overcomes the present art limitations outlined above by creating a device that offers a resistance to being forced much higher than currently known systems, respecting however the dimensional limits of locks imposed by the geometric shape of the space in which to accommodate standard European type cylinders. The aim is achieved through an innovative system of fastening, connection and transmission between the shell, the cylinder and the lock, consisting of a shaft having the dual function of transmitting the rotary motion from the cylinder to the lock and also to prevent the forced extraction of the whole shell-cylinder from the lock itself . The present art does not provide this technical feature, as the transmission of the rotary motion and the prevention of the forced extraction of the shell-cylinder from the lock are provided separately by using different components or parts.

In the present art some parts or components, such as the key, the rotor and the cam, are engaged in delivering the transmission , while the stator cylinder, transverse screws and fastening bolts of the protective shell are engaged in preventing the forced extraction of the device.

The high extraction resistance of the present invention is obtained through concentrating in a single component, the shaft, both functions of transmitting the rotary motion from the cylinder to the lock and preventing the forced extraction of the shell-cylinder from the lock itself .The concentration in a single component of both functions allows to add to the protective shell a fastening component with high mechanical properties in term of shape and size, compared to those components and parts used in the present art that are placed in different areas of the lock.

We now move on to describe in as greater detail as possible the preferred embodiment, but not exclusively, of the new burglar-proof device for the protection and operation of security locks, whose innovative characteristics were described above, together with the way it functions.

The invention is further described with the help of drawings .

Figure 1 shows a longitudinal section of the present invention.

Figure 2 illustrates an exploded axonometric view of the device object of this invention and the lock on which it is installed.

In the above drawings the following can be seen:

the protective outer shell (3) that contains the mechanisms, or devices, for the recognition of the key that can be of various types and having different operating principles, also referred to in the description of the invention as cylinder (7), with its key (8) .A switch (12) whose function is to connect the rotor of the cylinder (7)to the shaft (1) when the key (8) is inserted into the cylinder . The shaft (1), free to rotate in respect to the outer shell, having on one end ( A) the axial bond ( 2) and on the other end ( B) the thread (4), completed with the related nut blocking system (5) and a flange plate (10). The protective outer shell (3) is realized in two parts, or halves, in order to allow the insertion in its interior of the cylinder (7), the shaft (1), and all other shaft components.

The parts composing the protective outer shell (3) are fastened together by a proper elastic ring (14) placed in their respective circumferential grooves (15) and (16).

A cam (6), whose function is to operate the mechanism of the lock on which the device is installed, and a knob (13,) whose function is to operate the lock from the internal side, are also placed on the shaft

(1)·

The protective outer shell (3) is also provided with an anti-rotation pin (9) placed within the perimeter of the proper lock seat where a standard European type cylinder is ordinarily accommodated in the present art.

Said anti-rotation pin (9) has the functions of preventing the rotation of the protective outer shell (3) in respect to the lock in which it is installed as well as the function of adding another fastener of the whole. The fastener is represented by a screw (17), that is inserted into the threaded hole ( 18) located at its internal end (B).

Said anti- rotation pin (9) having such a shape or section that partially or completely fill the residual space available in the standard unified European cylinder section in addition to the shaft. The whole is installed on a lock designed to accomodate a standard European type cylinder (11). ^• In the inactive phase, i.e. when the key (8) is extracted from the cylinder (7), the shaft (1) carries out its function of preventing the removal or the forced extraction of the burglar-proof device, reacting and opposing, through axial constraints (2) and (5 ), attempts to remove the device from the lock (11) on which it is installed, while the anti-rotation pin (9) opposes the attempt to turn the device with respect to the lock (11).

In the active phase, i.e. during opening and closing of the lock, the shaft (1) performs its function of transmission of the rotation motion from the key (8) to the lock (11) with the switch (12), which acts connecting the rotor of the cylinder (7) to the shaft (1) when the key (8) is inserted into the cylinder (7) , or when it is internally operated by the knob (13). In, both phases the anti-rotation pin (9) is active. The present invention provides at least the following technological progress and benefits not found in the present state of the art in the specific field of application:

a) significantly increases the resistance to tearing of the cylinder locks and their protective outer shells without requiring any modification to locks designed to be operated by a standard European type cylinder;

b) Allows the installation of protective shells also on those type of locks made for European type cylinders but not having proper holes for the passage of fastening screws ;

c) The shaft, which is responsible for the mechanical strength of the device, has the maximum size possible consistent with the geometric dimensions imposed by the unification of the standard European cylinders;

d) Allows to add the resistance to tearing of this invention to other fastening systems already existing in the present art.