The present invention relates to an anti-intrusion cylinder for locks, in particular in order to prevent, using the lock alone, the key from being cloned by making a perfect impression of the internal components for coding the lock.
Currently locks exist that comprise a cylinder (within which the key must be inserted for opening) provided with a stator and with a rotor which are mutually coupled by way of a plurality of pins and counterpins that can slide within stator and rotor channels: each channel of the stator is facing and aligned with the respective channel of the rotor when the cylinder is in the locked configuration (key taken out, or inserted but not rotated with respect to the insertion configuration).
Between the bottom of the channel of the stator and the lower surface of the counterpin there is an elastic element that has an axial action designed to keep the counterpin away from the bottom, unless external actions entail lowering the counterpin (for example the insertion of the key in the cylinder).
The key, by way of its contoured (encoded) profile, acts on the upper surface of the pins, lowering them and bringing the discontinuity surface that separates the bottom of the pin from the apex of the counterpin into perfect alignment with the discontinuity surface present between rotor and stator, which can be substantially mutually disengaged (with the key inserted).
The rotor (with the key inserted, therefore with the pins lowered according to the coding) can be rotated by turning the head of the key which protrudes from the cylinder: in this manner the opening of the lock is permitted.
It is known that if an impression of the key is available, it is possible to obtain a perfect working copy thereof.
Methods are further known that make it possible to copy the key starting from the lock.
A non-encoded key is used, of the same type as that associated with a determined cylinder. Such key has previously been shaped by making a succession of grooves of depth equal to or deeper than the maximum depth present in the original key and filling such grooves with plastic elements (wax and plasticine) with a predefined degree of elasticity and ductility.
One then proceeds by alternately turning, clockwise (the direction for opening) and anticlockwise (the direction for locking), the rotor by way of such key, thus determining the oscillation of the pins of the cylinder.
Following a certain number of successive alternate rotations, clockwise and anticlockwise, of the key, the individual pins, under the thrust of the respective elastic elements, gouge the plastic filling element of the respective grooves, advancing until they bring the discontinuity surface that separates the bottom of the pin from the apex of the counterpin into perfect alignment with the discontinuity surface present between rotor and stator (the position in which the rotor can be rotated by turning the head of the key which protrudes from the cylinder: in this manner the opening of the lock is permitted).
One can succeed therefore in acquiring, with only the lock available, a perfect impression of the internal encoding components of the lock and therefore in making, starting therefrom, a perfect copy of the original key.
Conventional construction solutions, although adapted to block any intrusion actions perpetrated on the cylinders, do not make it possible to guard against the possibility of cloning the key from the lock alone, with consequent intrinsic lack of security against tampering with conventional cylinders.
Document D1 discloses an anti-intrusion cylinder for locks according to the preamble of claim 1. Furthermore, in this document a single contoured annular body is fitted, with mechanical play, to the over the mushroom-shaped terminal of a pin shank.
The aim of the present invention is to solve the above mentioned drawbacks, by providing an anti-intrusion cylinder for locks which is highly secure against methods of cloning the key from the lock alone.
Within this aim, an object of the invention is to provide an anti-intrusion cylinder for locks which is low cost, easily and practically implemented and safely applied.
This aim and these and other objects which will become better apparent hereinafter are achieved by an anti-intrusion cylinder for locks of the type comprising a stator which is provided with a substantially cylindrical longitudinal cavity for accommodating a rotor with a longitudinal seat for the insertion of a key, said rotor and said stator comprising a plurality of channels, which are substantially aligned and facing when the cylinder is in the locked configuration, said channels accommodating respective pins, counterpins and optional elastic means which are adapted to prevent the rotation of the rotor in the stator in the absence of the key from said longitudinal seat, at least one of said pins comprising a shank, said shank being provided with a mushroom-shaped terminal with a diameter smaller than the diameter of said shank, said terminal being faced toward and proximate to the corresponding counterpin, characterized in that at least two contoured annular bodies with a substantially similar diameter to the diameter of said channel are mutually arranged in a column and are fitted, with mechanical play, over said mushroom-shaped terminal.
Further characteristics and advantages of the invention will become better apparent from the detailed description of a preferred, but not exclusive, embodiment of the anti-intrusion cylinder for locks according to the invention, which is illustrated by way of non-limiting example in the accompanying drawings, in which:
With reference to the figures, the reference numeral 1 generally indicates an anti-intrusion cylinder for locks.
The cylinder 1 comprises a stator 2 which is provided with a substantially cylindrical longitudinal cavity 3 for accommodating a rotor 4.
The rotor 4 in turn is affected by a longitudinal seat 5 which is intended to receive a key 6: the insertion of the respective key 6 into the seat 5 determines the ability to rotate the rotor 4 with respect to the stator 2, thus opening the lock with which the cylinder 1 is associated.
The rotor 4 and the stator 2 comprise a plurality of channels 7, which are substantially aligned and facing when the cylinder 1 is in the locked configuration.
The channels 7 accommodate respective pins 8, counterpins 9 and optional elastic means 7a which are adapted to prevent the rotation of the rotor 4 in the stator 2 in the absence of the key 6 in the longitudinal seat 5.
According to the invention, at least one of the pins 8 can positively comprise a shank 10, which is accommodated slideably in the stator portion 2 of a respective channel 7.
The shank 10 is provided, according to the invention, with a mushroom-shaped terminal 11 with a diameter smaller than the diameter of the shank 10.
The terminal 11 is faced toward and proximate to the corresponding counterpin 9, in particular the end face 12 of the counterpin 9.
According to the invention, at least two contoured annular bodies 13, which has a substantially similar diameter to the diameter of the channel 7, is fitted, with mechanical play, over the mushroom-shaped terminal 11.
With reference to a specific embodiment of undoubted practical and applicative interest, the mushroom-shaped terminal 11 can positively comprise a stem 14, which has a first diameter of a value comprised between 1/6 and 3/4 of the diameter of the channel 7, surmounted by a plug 15, which has a second diameter of a value comprised between 1/5 and 5/6 of the diameter of the channel 7.
From observing the accompanying figures it can be seen that, with reference to the cylinder shown by way of example therein, the mushroom-shaped terminal 11 can be shaped like the head of a screw engaged axially on a respective pin 8, on an end face thereof.
The contoured annular body 13 comprises an inner through opening 16 which has a diameter larger than the first diameter of the stem 14 and than the second diameter of the plug 15.
Moreover, the maximum diameter of the plug 15 can also advantageously be smaller than the diameter of the through opening 16 of the contoured annular body 13, especially if the pin 8 is made in one piece that comprises its terminal 11. In this manner it will be possible to engage the contoured annular body 13 on the pin 8 (in particular on its terminal 11) easily.
The contoured annular body 13 can move with respect to the mushroom-shaped terminal 11 (while still remaining locked between the plug 15 and the lower end of the pin 8): in particular it can perform translational movements, arranging itself according to various possible misalignments with respect to the coaxial and aligned condition, and rotational movements, inclining itself with respect to the axis of the stem 14.
Obviously the combination of the translation and rotation movements will ensure a considerably higher level of security for the cylinder 1 because, as will be seen hereinafter, the annular body 13 can be locked between the rotor 4 and the stator 2 (in the event of attempts at tampering made using a non-encoded, previously-shaped key 6a provided with encoding grooves filled with plastic elements P) according to an unlimited number of different configurations, thus preventing the fraudulent opening of the cylinder 1.
It is useful to note that the contoured annular body 13 (fitted, with a predefined mechanical play, over the stem 14 of the mushroom-shaped terminal 11) is locked between the plug 15, below, and the end face of the shank 10, above.
The locking of the contoured annular body 13 in such position is due to the fact that it is compressed, by the action of the elastic element 7a, between the counterpin 9 and the pin 8 and fitted over the terminal 11.
In this manner, besides ensuring the necessary security against tampering, the mechanical stability of the entire cylinder 1 is also ensured, since it is not possible for the annular body 13 to accidentally disengage from the mushroom-shaped terminal 11.
With reference to an embodiment of undoubted practical and applicative interest, the inner through opening 16 of the contoured annular body 13 can conveniently comprise a first through hole 17 with a diameter that is complementary to the diameter of the plug 15 (in order to prevent the accidental disengagement of the annular body 13 from the mushroom-shaped terminal 11) and an external receptacle 18 with a diameter larger than the diameter of the plug 15; such receptacle 18 is adapted to temporarily accommodate the plug 15.
Saying that the first through hole 17 has a diameter that is complementary to the diameter of the plug 15 means that it will have a measurement proximate to that of the diameter of the plug; substantially it can be slightly smaller, the same, or slightly larger.
It is useful to point out further that the contoured annular body 13 can profitably have an outer shape structure that is preferably chosen from among cylindrical, toroidal, cask-shaped, frustum-shaped, prismatic, truncated pyramid shaped, teardrop portion shaped and a combination thereof.
According to the shape selected, the annular body 13 will perform a different locking action in the event of attempts at tampering.
In fact a shape structure that has a curved or roundish outer shape (for example toroidal, cask-shaped, teardrop portion shaped) will facilitate the annular body 13 in taking up inclined configurations (inclined with respect to the mushroom-shaped terminal 11) in that the absence of corner edges will enable easier rotation movements.
By contrast, a cylindrical shape structure, or one that is frustum-shaped, prismatic, truncated pyramid shaped and the like, will be more subject to translational misalignment movements of the axis of symmetry of the body 13 with respect to the axis of symmetry of the mushroom-shaped terminal 11.
Similarly, the pin 8 can also have an outer shape structure preferably chosen from among cylindrical, toroidal, cask-shaped, frustum-shaped, prismatic, truncated pyramid shaped, teardrop portion shaped and a combination thereof.
The possibility is not ruled out of adopting different shapes. For the pin 8 as well, according to the shape selected, the annular body 13 will perform a different locking action in the event of attempts at tampering.
In fact a shape structure that has a curved or roundish outer shape (for example toroidal, cask-shaped, teardrop portion shaped) will facilitate the annular body 13 in taking up inclined configurations (inclined with respect to the mushroom-shaped terminal 11) in that the absence of corner edges will enable easier rotation movements.
By contrast, a cylindrical shape structure, or one that is frustum-shaped, prismatic, truncated pyramid shaped and the like, will be more subject to translational misalignment movements of the axis of symmetry of the body 13 with respect to the axis of symmetry of the mushroom-shaped terminal 11.
According to the invention and for undoubted security against attempts at tampering, the contoured annular bodies 13 are at least two in number, mutually arranged in a column and fitted, with mechanical play, over the mushroom-shaped terminal 11.
The presence of several superimposed annular bodies 13 ensures a considerable increase of the possible locking configurations that can occur in the event of attempts at tampering, with consequent increase of the intrinsic security of the cylinder 1.
It should be noted that the contoured annular bodies 13 mutually arranged in a column can be mutually identical or different.
In the second case, at least one first contoured annular body 13 could also comprise a recess for the partial accommodation of at least one portion of at least one second contoured annular body 13, so that they can also assume a configuration of mutual mating (and optional partial accommodation of the one in the other).
The presence of such recess in the first contoured body 13 and of the corresponding portion in the second contoured body 13 is in any case not necessary for the correct operation of the invention; the contoured bodies 13 could in fact have their mutual abutment faces flat or contoured completely independently of each other.
It should be noted that the cylinder 1 according to the invention can achieve extremely high standards of security if there is a plurality (in particular at least two) of pins 8 provided with the shank 10 with a mushroom-shaped terminal 11 (of diameter smaller than the diameter of the shank 10), and with at least one contoured annular body 13 which is fitted, with mechanical play, over the mushroom-shaped terminal 11: such pins 8 according to the invention can be effectively distributed in different channels 7.
Operation of the present invention is the following.
When using the specific key 6, as shown in the accompanying
However, if an ill-intentioned individual attempts to tamper with the cylinder 1 according to the invention, through the use of a non-encoded, previously-shaped key 6a provided with encoding grooves filled with plastic elements P, the pin 8 provided with the mushroom-shaped terminal 11 will become locked.
In particular, the ill-intentioned individual will exert a mechanical moment in order to impose a rotation of the rotor 4 clockwise and, subsequently, anticlockwise, by way of such key 6a, in order to cause the oscillation of the pins 8 (as shown in the accompanying
The pin 8 under the action of the elastic element 7a will therefore compress the plastic filler element P, sliding, therefore, gradually upward inside the channel 7, until it brings the end face of the shank 10 into substantial alignment with the discontinuity surface between the stator 2 and the rotor 4 (as shown in the accompanying
In this configuration, the repeated action of rotating the rotor 4 will mean an offset of the annular body 13 with respect to the pin 8 over which it is fitted, with the impossibility of raising such pin 8 further (as shown in the accompanying
In fact, the annular body 13 will always abut with a surface thereof on the rotor 4, making a further lifting of the pin 8 inside the respective channel 7 impossible, and making it effectively impossible to make a perfect impression of the internal encoding components of the lock and therefore to make a perfect copy of the original key 6.
Advantageously the present invention solves the above mentioned problems, by providing an anti-intrusion cylinder 1 for locks which is highly secure against methods of cloning the key from the lock alone.
Positively the present invention makes it possible to provide an anti-intrusion cylinder 1 for locks relatively simply and at substantially low cost: such characteristics ensure a secure practical application of the present invention.
The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.
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.