HIGH SECURITY CYLINDER LOCK AND KEY THEREFOR

Abstract: The security cylinder lock is characterized by the existence of a system of interlocking circumferential grooves (21) and ridges (5) affecting both cylinder shell (4) and the rotatable plug (6), and by a cylindrical key (10) with a plurality of "V"-shaped skew cut bits (12). Given that each spring-biased (3) tumbler pin (1) and driver (2) pair is placed inside radially-oriented holes (11) intersecting the circumferential grooves (21) and ridges (5), the ability of the rotatable plug to rotate within the outer shell, depends upon the angular and elevational positioning of each tumbler pin/driver pair, which, upon the insertion of the properly bitted key, assumes a positioning that allows their interlocking contact surfaces (15, 19) to align themselves with the circumferential grooves (21) and ridges (5) in each location that a tumbler pin hole (11) intersects a groove and a ridge.

Description: HIGH SECURITY CYLINDER LOCK AND KEY THEREFOR TECHNICAL FIELD This invention relates to cylinder-type locks and more specifically to those of the type with dual locking mechanisms having reciprocating and rotating tumbler pins. In particular, the rotation of the rotatable plug inside the cylindrical shell depends on two variables: - the elevational position of tumbler pins and drivers; the angular orientation of said tumbler pins and drivers inside their housing. SUMMARY DESCRIPTION OF THE INVENTION The new high security cylinder-type lock contains a cylindrical plug (6)- hereinafter called the rotatable plug- which rotates inside a cylindrical shell (4) - hereinafter called the outer shell- with a keyway configured to receive a key, as well as a set of radially- oriented tumbler pin holes (11) with spring-biased tumbler pins (1) and drivers (2) placed inside these holes. The lock is also provided with a cylindrical-shaped key (10) having a plurality of skew cut bits (12) along its cylindrical surface. The lock also features a unique dragging system mechanism (9). On the internal surface of the outer shell, which is in contact with the external surface of the rotatable plug, circumferential grooves (21) are found. These circumferential grooves have a profile configured to interlock with corresponding circumferential ridges (5) found on the external surface of the rotatable plug. Each tumbler pin has at its upper tip a ridge (15) configured to fit inside a groove (19) at the lower tip of its corresponding driver. The shape in side-section of the tumbler pin ridge has the same shape in side-section of the circumferential ridge found on the external surface of the rotatable plug. Similarly, the shape in side-section of the groove at the lower tip of each driver is of the same shape in side-section of the circumferential groove found on the internal surface of the outer shell. The key includes a bow portion (17), designed to be grasped by a user, and a cylindrical portion (10) extending away from the bow portion. The cylindrical portion has a number of "V"- shaped skew cut bits ( 12) along its cylindrical surface. These skew cuts differ from one another in: their position along the longitudinal axis and around the circumference of the cylindrical portion of the key; - their varying depth; their angular orientation with respect to the longitudinal axis of the cylindrical portion of the key. The essential concept of the invention "A high security cylinder lock with dual locking mechanism controlled by circumferential grooves and ridges and a three-dimensional key therefor " is based on the exclusive principle of functioning that we call "principle of functioning with a system of interlocking circumferential grooves and ridges ". By means of such principle, this invention has introduced relevant innovations with respect to prior art in dual-locking function cylinder lock. The above mentioned exclusive principle is now described in more technical detail. Given that each tumbler pin and driver pair can be rotated, as well as moved axially inside its radially-oriented hole, the control of its elevational and angular positioning is made possible by the circumferential grooves (21) and ridges (5) found along the contact surfaces of both the outer shell (4) and the rotatable plug (6). The geometrical continuity of these circumferential grooves and ridges, and consequently, the ability of the rotatable plug to rotate within the outer shell, depends upon the angular and elevational positioning of each tumbler pin and driver pair, which, upon the insertion of the properly bitted key, assume a positioning that allows their contact surfaces (15; 19) to align themselves with the circumferential grooves (21) and ridges (5) in each location that a tumbler pin hole (11) intersects a groove and a ridge. The above-described exclusive principle of functioning can operate as a result of special technical features existing in each part of this high security cylinder lock. The description of the above mentioned special technical features will now be presented more in detail with reference to each single component of this cylinder lock. KEY (fig.2) The key for use in this invention, constructed according to a preferred embodiment of the present invention, has a bow portion (17) and a cylindrical portion (10) extending away from the bow portion. The cylindrical portion has a cone-shaped end (25) and a plurality of "V"- shaped skew cut bits (12) along its cylindrical surface. Such "V" -shaped skew cuts differ from one another in: a) their position along the longitudinal axis and around the circumference of the cylindrical portion ; b) their varying depth; c) their angular orientation with respect to the longitudinal axis of the cylindrical portion. OUTERSHELL AND ROTATABLE PLUG (fig.l) The internal surface of the outer shell interlocks with the external surface of the rotatable plug by means of circumferential grooves (21) and ridges (5), as opposed to the prior art in which the same surfaces of the outer shell and the rotatable plug are smooth and not interlocking. Figure 4 shows a preferred embodiment of the current invention, emphasizing its characteristic grooves and ridges. It must be emphasized that in the present invention the outer shell (4) has been manufactured as two semi-circular shells (as shown in figure 1) joined by a coupling flange (7) in order to: allow the rotatable plug (6) to be fitted inside the outer shell ; allow the circumferential ridges found along the external surface of the rotatable plug to interlock with the corresponding grooves found along the internal surface of the outer shell. TUMBLER PINS AND DRIVERS (fig.3) • tips that make contact with the key ( hereinafter, the "lower tips") An its lower tip, each tumbler pin (1), constructed according to a preferred embodiment of the present invention, is wedge-shaped (24), in order to allow it to fit inside its corresponding "V"- shaped skew cut bit (12) found along the cylindrical surface of the key. • tips that make contact with the drivers ( hereinafter, the "upper tips") The upper tip of each tumbler pin has a ridged surface (15) configured to fit inside a corresponding groove (19) found at the lower tip of its corresponding driver (2). The shape in side-section of the tumbler pin ridge (15) is the same in side-section of the circumferential ridge (5) on the external surface of the rotatable plug. Similarly, the groove (19) in side-section at the lower tip surface of each driver is the same in side-section as the circumferential groove (21) found on the internal surface of the outer shell. On these surfaces, more specifically where the circumferential grooves and ridges are found, radially-oriented holes (11) have placed, thus interrupting their geometrical continuity. DRAGGING SYSTEM MECHANISM f fig.l. fig.2 The key is provided with a special dragging system mechanism, which allows the transmission of the rotatory motion from the key to the rotatable plug. This technical mechanism is necessary, as the key has a cylindrical shape, which in itself could not transmit such movement without the aid of a special dragging system mechanism. The dragging system mechanism, in the preferred embodiment, consist of the following components: A two-pronged tongue (9) extending from the bow portion of the key (17); A slot (20) cut across a ring-shaped frontal projection of the rotatable plug; - A cylindrical pin (18) that holds together the bow portion (17) and the cylindrical shaft (10) of the key, passing through an oval-shaped hole (8) found on the bow portion and a hole (23) found on the tip of the cylindrical shaft of the key; The oval-shaped hole (8) functions as a "buttonhole" in that it permits the circular pin to (18) slide back and forth within it. As a result, the tongue is able to move up and down within the notch. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective, exploded view of a cylinder lock according to this invention; Figure 2 is a perspective, exploded view of a key constructed according to the invention; Figure 3 is perspective, exploded view of a tumbler pin and driver pair with its accompanying spring according to the invention, illustrating: the grooved (19) and ridged (15) interlocking surfaces; the lower tip of the tumbler pin (24), which comes into contact with the "V-shaped skew cut bit on the key surface; Figure 4 is a perspective with a side sectional view of a cylinder lock according to this invention, with the key inserted into the keyway. BACKGROUND ART Many significant technical improvements in cylinder lock art have been introduced onto the market in the last two or three decades. These have had the purpose, among others, of increasing the number of lock combinations and/ or the complexity of key duplication. Typically, improvements in increasing the number of keying combinations have been obtained by: increasing the number of tumbler pins and holes; producing keys with very complex shapes or variations in the key profiles and the corresponding keyway in the cylinder; varying the shapes of tumbler pins and drivers. Such improvements have also made lockpicking techniques, including impression methods of producing false keys, more difficult. Cylinder locks have also been constructed to make the reproduction of keys more complex. Such improvements have mainly consisted of unique shaped bittings and the variation of the axial and radial orientations of each tumbler pin and driver pair. As a result, keys with different shapes have been constructed (i.e. flat keys, crown-shaped keys, nailed-shaped keys, etc.). Despite improvements in the well-designed cylinder lock art, the security of these locks is still limited due to, among others, the following factors: unauthorized duplications may be easily obtained by use of conventional machines that operate on the premise of the key having one or two axes; at present, keys have a simple design and structure whose salient points may be easily interpreted by an expert and may also be reproduced by impression methods or even by use of simple cutting tools. The limited number of keying combinations is due to a series of factors such as: a) the market demand for small and thin keys, which reduce the range of lock components; b) key production being based only on one or two dimensions: the axial positioning and the depth of the key bittings; c) the technical limitation of increasing the number of tumbler pins above a certain quantity, without increasing the cost and complexity of the lock. At the present, lock mechanisms are also easily vulnerable to lockpicking techniques, including manipulation with a lockpick or with a key made of a malleable material. Once again, lockpicking techniques are possible and the security of the lock is decreased because the keys have only two dimensions and therefore, can be easily copied by exploiting the geometrical and positional tolerance of various components. Into this technological background entered the well-known Medeco Security Locks Inc. U.S. Patents n. 3.722.240, granted March 23, 1973 and n. 30.198 issued January 29,1980. The above-mentioned patents greatly improved the state of the cylindrical lock art by introducing the principle of " angular positioning of tumbler pins ", or a " double locking system". The value of the Medeco inventions are based on the introduction of the rotational positioning of the tumbler pins, in addition to the traditional elevational positioning of the pins. This factor significantly increased the number of available keying combinations. Increasing the number of key bittings incrementally resulted in a higher number of unique keys, greatly reducing the possibility of a key operating a cylinder other than its own. This invention also rendered key duplication possible only by means of special machines, able to reproduce not only the depth but also the angular positioning of the bittings. The increase of the numbers of key bittings also compromised the strength of the key blade. Specifically, the bittings were cut into the key blade at various depths and, as a result, certain areas of the key blade had more material removed from them, and were thus weaker than other areas of the blade. As a consequence the key became more susceptible to breakage or other failure. Through U.S. Patent n. 96/15000, granted on September 19, 1995, Medeco Security Locks Inc. disclosed an improved key possessing sufficient strength to prevent breakage, yet permitting the placement of both shallow and deep bittings into the key blade. Notwithstanding the above mentioned technological progress in this field, the current market demands a more sophisticated and secure cylinder lock, with a higher number of combinations, that does not permit key reproduction with conventional machines. DISCLOSURE OF THE INVENTION AND MODES FOR CARRYING OUT IT The present invention provides a unique cylinder lock mechanism, which also offers a technical solution to market demands for high security. This invention provides for, in addition to the technical features already described above, the production of cylinder locks where the radially oriented tumbler pin holes (11) have a "random" disposition (i.e., not in linear alignment with one another) along the circumference of the rotatable plug and the outer shell (as shown in fig.l). The present art does not provide this technical feature, as the tumbler pin holes have been placed in alignment with one another and run in one line that is parallel to the rotation axis of the cylinder lock. The additional feature introduced with this invention allows for the production of a more complex key, whose bits have been cut at random positions around the cylindrical surface of the key (fig.2). The present invention has introduced the innovative and exclusive principle of functioning, already disclosed in the summary, and called "principle of functioning with a system of interlocking circumferential grooves and ridges." This principle of functioning is based on an innovative technical concept that has the intrinsic ability to be expanded upon in future designs and is superior to the ones found in the present art. This principle of functioning permits, among other things, the following: The variation in the positioning of the tumbler pins and drivers around the cylindrical surface of both the rotatable plug and the outer shell, thus overcoming the current limitation, existing in the dual locking function cylinder locks art, of the tumbler pins being in alignment with one another and running along one line that is parallel to the rotation axis of the cylinder lock; The control of rotational positioning of both the tumbler pins and drivers. In the present art this control does not extend to the drivers; the production of a stronger key, as the bittings cut around a cylindrical surface, even if deep, leave an amount of material sufficient to allow for the mechanical integrity of the key provided by the variable positioning of these bits (see figure 2). In this way, weak points leading to key breakage have been eliminated; a key with a separate and special dragging system mechanism that allows the cylindrical key to freely rotate inside its keyway with respect to the rotatable plug. This technical detail also enormously facilitates the insertion and extraction of the key; the insertion of the key from any angular position; the production of a cylinder lock with a practically infinite number of keying combinations, even in a lock with only six tumbler pins. This would be possible because of: a) the "random" disposition of the radially-oriented tumbler pin holes around the cylindrical surfaces of the rotatable plug and outer shell, and accordingly; b) the "random" positioning of the tumbler pins and drivers and their corresponding bittings around the cylindrical surface of the key; c) the variable angular orientation of the key bittings with respect to the longitudinal axis of the key; if desired, an increase of the number of tumbler pins without adversely affecting the length of the key. In the present art, where the key bits are in linear positioning, the addition of a tumbler pin to the lock mandates an additional key bitting that lengthens the blade of the key; The limitation of key reproduction to sophisticated machines able to reproduce bits having different depths, angular positions and different positions along the cylindrical surface of the key; The production of extremely "enigmatic" keys, which are difficult to be memorized and/ or reproduced (i.e., through impression methods); The manufacture of bilateral cylinders, so that the key can be inserted into the same cylinder from both the front and the rear; Hereinafter, the preferred embodiment of the new high security lock, already briefly described in the previous paragraph, is now described, together with its functioning, in greater detail. The new high security cylinder lock contains a cylindrical plug - hereinafter called the rotatable plug (6)- which rotates inside a cylindrical shell - hereinafter called the outer shell (4)- with a keyway configured to receive a key, as well as a set of radially-oriented tumbler pin holes (11) with spring-biased (3) tumbler pins (1) and drivers (2) placed inside these holes. The lock is also provided with a cylindrical-shaped key (10), which has a plurality of "V'-shaped skew cut bits (12) extending along its cylindrical surface. The lock also contains a unique dragging system mechanism. On the internal surface of the outer shell, which is in contact with the external surface of the rotatable plug, circumferential grooves (21) and ridges (5) are found. These circumferential grooves have a profile configured to interlock with corresponding circumferential ridges made on the external surface of the rotatable plug. Each tumbler pin (1) has at its upper tip a ridge (15) configured to fit inside a corresponding groove (19) at the lower tip of its corresponding driver (2). The shape in side-section of the circumferential ridges found on the external surface of the rotatable plug have the same shape in side-section of each tumbler pin ridge found on the upper tip of the pin itself, where it makes contact with the driver. Similarly, the shape in side-section of the circumferential grooves found on the internal surface of the outer shell are of the same shape in side-section of the groove at the lower tip of each driver, where it makes contact with the tumbler pin. The ridges and grooves of the pins and drivers (19; 15), interlocking with one another, align themselves with the circumferential grooves and ridges (21; 5) found on the surfaces of the outer shell and rotatable plug, provided that each tumbler pin and driver pair (1; 2) assumes its unique elevational and rotational position upon the insertion of the properly configured key. This alignment permits the geometrical continuity of the circumferential grooves and ridges, and therefore, the ability of the rotatable plug to rotate within the outer shell. The key (fig.2) includes a bow portion (17), designed to be grasped by a user, and a cylindrical portion (10) extending away from the bow portion. The cylindrical portion has a number of "V- shaped skew cut bits (12) along its cylindrical surface. Such "V'- shaped bits differ from one another in: - their position along the longitudinal axis and the circumference of the key; their varying depth; their angle with respect to the longitudinal axis of the key. The special dragging system mechanism is necessary, as the cylindrical shape of the key cannot transmit the rotatory motion to the rotatable plug on its own. The mechanism also offers many advantages in both the insertion and extraction of the key phases allowing, among other things, the insertion and the extraction of the key from any angular orientation and the independent rotation of the key with respect to the rotatable plug to permit the tumbler pins to be moved away from the rotation axis of the key. The above-described dragging system mechanism, in the preferred embodiment, consists of the following components: A two-pronged tongue (9) extending from the bow portion of the key(17); A slot (20) cut across a ring-shaped frontal projection of the rotatable plug; A cylindrical pin (18) that holds together the bow portion (17) and the cylindrical shaft (10) of the key, passing through an oval-shaped hole (8) found on the bow portion and a hole (23) found on the tip of the cylindrical shaft of the key; - The oval-shaped hole (8) functions as a "buttonhole" in that it permits the circular pin to (18) slide back and forth within it. As a result, the tongue is able to move up and down within the notch. The entire dragging system mechanism has the following purposes: - the tongue (9), upon the insertion of the key in the lock, fits inside the corresponding slot (20) cut across a ring-shaped frontal projection of the rotatable plug thus allowing the rotation of the rotatable plug together with the key; in the phase of key extraction, the sliding motion of the tongue within the notch permits the release of the tongue from the slot of the rotatable plug and thus allows: a) the independent rotation of the key inside the rotatable plug; b) the separation of the tumbler pins from the "V'-shaped cut bittings of the key; c) the extraction of the key by means of an easy helicoidal movement ( i.e., the key may be easily rotated within the rotatable plug and moved gradually out of the keyway in a singular motion). The operation of the security lock disclosed in this invention may be described starting from the insertion of the key. The tumbler pins (1) and drivers (2) are at a resting position inside their respective housings (the radially-oriented holes (11) of the rotatable plug and outer shell), thus blocking the rotation of the rotatable plug (6) within the outer shell (4). When the key (10) is inserted into the lock, the tumbler pins and drivers move away from the key rotation axis by the thrust of the cone-shaped tip (25) of the key, the motion of which compresses and loads the springs (3). The key continues its run to the end of the keyway inside the rotatable plug. During this phase the wedge-shaped lower tip (24) of each tumbler pin fits inside its corresponding "V"-shaped bit (12) cut on the cylindrical surface of the key. Once the fitting of all tumbler pins into the corresponding bittings has taken place, each tumbler pin and driver pair assumes a position, which complies with each of three conditions imposed by a key bitting: > its position along the longitudinal axis and around the circumference of the key; > its varying depth ; > its angular positioning with respect to the longitudinal axis of the key. Only upon the insertion of a properly bitted key into the lock's keyway, does each interlocking tumbler pin and driver pair rotate and assume a unique position that allows the ridge (15) on the upper tip of the pin to align itself with the circumferential ridge (5) on the exterior surface of the rotatable plug, where the radially-oriented hole (11) housing the pin interrupts it. At the same time, the grooved (19) lower tip of its corresponding driver, which already interlocks with the ridged upper tip of the pin, aligns itself with the circumferential groove (21) of the outer shell that the radially- oriented hole (11) housing the driver interrupts in the same location. As a consequence of the above events, the geometrical continuity of the circumferential grooves and ridges has been achieved and the rotation of the rotatable plug within the outer shell has thus been enabled. Additionally, the dragging system mechanism aids this rotation in that it permits the above-described tongue (9) to fit inside its corresponding slot (20) on the rotatable plug, catching its ring-shaped frontal projection and "dragging" the entire plug with it in the rotation of the key. In the phase of key extraction, the tongue (9) is released from its corresponding slot (20), thus permitting: the key to independently rotate inside the rotatable plug, thereby thrusting the tumbler pins and drivers away from the rotation axis of the key and also favoring the extraction of the key itself; - the rejumbling of the tumbler pins and drivers, thus blocking the rotation of the rotatable plug within the outer shell.

Claims: CLAIMS What is claimed is: 1. A high security cylinder lock with tumbler pins and drivers rotating as well as moving axially inside their radially-oriented holes, and a three-dimensional cylindrical key; the lock comprising: A cylindrical plug, hereinafter called the rotatable plug, with an internal axial- cylindrical channel into which the key is inserted, known as the keyway. The rotatable plug rotates inside a cylindrical shell, hereinafter called the outer shell; A set of radially-oriented holes intersecting the rotatable plug and outer shell converging at the keyway. The radially-oriented holes containing spring-biased tumbler pins and drivers; a cylindrical-shaped key with a plurality of "V'-shaped skew cut bits extending along and around its cylindrical surface; a dragging system mechanism; - the external surface of the rotatable plug, which is in contact with the internal surface of the outer shell, being characterized by the presence of circumferential ridge (s) of any polyangular shape; tumbler pins having wedge-shaped lower tips which come into contact with the key, while their upper surfaces contain a ridge(s) forming a profile(s) configured to interlock with a corresponding groove(s) found on the lower surfaces of their corresponding drivers; the interlocking profiles of the grooves and ridges of the pins and drivers having the same profiles as the interlocking circumferential grooves and ridges found along the surfaces of the rotatable plug and outer shell; - the radially-oriented holes containing pins and drivers and intersecting the circumferential grooves and ridges found on the contact surfaces of the rotatable plug and outer shell; the holes being aligned with the corresponding skew cut bits of the key; the holes having a "random" dispositioning within the rotatable plug and outer shell in accordance with both the above mentioned features; the internal surface of the outer shell being characterized by circumferential grooves of any polyangular shape, configured to interlock with corresponding symmetrical ridges on the external surface of the rotatable plug ; drivers being spring-biased, having at their lower tips, which make contact with the tumbler pins, grooved surfaces configured to fit inside corresponding ridged surfaces at the upper tips of the corresponding tumbler pins; the profiles of the ridges and grooves found on the tumbler pins and drivers respectively, having same profile as the circumferential grooves and ridges on the surfaces of both the outer shell and the rotatable plug; - the ridges and grooves found on the surfaces of the tumbler pins and drivers designed for contact with one another, once interlocking, creating a geometrical continuity of the circumferential grooves and ridges along the interlocking surfaces of the outer shell and rotatable plug, when, upon insertion of the proper key, each key bitting determines the proper elevational and rotational position of its corresponding pin and driver; the key having a cylindrical shape, a cone-shaped tip and a plurality of "V'- shaped skew cut bits along its cylindrical surface; such "V"-shaped bits differing from one another in their positions along the longitudinal axis and circumference of the key, in their varying depths and in their angular positioning with respect to the longitudinal axis of the key; the dragging system mechanism being able in the key insertion phase to allow the rotation of the rotatable plug within the outer shell and in the extraction phase to release the key from the rotatable plug, thus permitting the key itself, by virtue of its cylindrical shape, to rotate independently with respect to the rotatable plug; 2. A lock according to claim 1) wherein the groove(s) found on the outer shell may be conversely found on the rotatable plug, and the ridge(s) found on the rotatable plug may be conversely found on the outer shell, and wherein the tumbler pins whose ridges are designed for continuity with the circumferential ridges on the rotatable pl u conversely appear as grooves, and the grooves in the drivers designed for continuity with the circumferential grooves in the outer shell conversely appear as ridges; 3. A lock according to claim 1) and 2) wherein the key has a polyangular shape in cross- section; 4. A lock according to claim 1) and 2) wherein the axial channel ( keyway) into which the key is inserted has a polyangular shape in cross-section; 5. A lock according to claim 1) and 2) wherein the bittings of the key have any polyangular shape; 6. A lock according to claim 1) and 2) wherein the bittings of the key have a curvilinear shape; 7. A lock according to claim 1) and 2) wherein the tumbler pins have at their tips that make contact with the corresponding key bittings, any polyangular shape; 8. A lock according to claim 1) and 2) wherein the tumbler pins have at their tips that make contact with the corresponding key bittings, a curvilinear shape; 9. A lock according to claim 1) and 2) wherein the circumferential grooves and ridges found on the outer shell and on the rotatable plug have a curvilinear shape in side- section; 10. A lock according to claim 1) and 2) wherein the surfaces of the pins and drivers designed for interlock with one another are of different shapes in side-section to the surfaces of the rotatable plug and outer shell designed for interlock with one another, but nonetheless provide for continuity between these surfaces and permit the rotatable plug and tumbler pins together to rotate within the outer shell and drivers; 11. A lock according to claim 1) and 2) wherein the interlock configuration(s) between tumbler pins and drivers do(es) not permit their reciprocal axial separation; 12. A lock according to claim 1) and 2) wherein (an) additional element(s) is found between the tumbler pins and drivers having the purpose of creating a hierarchical lock and/ or providing protection from lock manipulation. AMENDED CLAIMS [received by the International Bureau on 10 May 2000 (10.05.00); original claim 1 amended ; new claim 13 added ; remaining claims unchanged (4 pages)] What is claimed is: 1. A high security cylinder-type lock with dual locking mechanism having tumbler pins and drivers rotating as well as moving axially inside their radially-oriented holes, and a three-dimensional cylindrical key; the lock comprising: - A cylindrical-shaped key (10) with a plurality of "V'-shaped skew cut bits (12) extending along and around the surface of its cylindrical portion; - A rotatable plug (6), with an internal axial-cylindrical channel into which the key is inserted, known as the keyway. The rotatable plug rotates inside a cylindrical shell, called the outer shell (4); - A set of radially-oriented tumbler pin holes (11), having a "random" dispositioning (i.e. not in linear alignment with one another) along the circumference of the rotatable plug and outer shell, intersecting them and converging at the keyway. The radially- oriented holes being aligned with the corresponding "V- shaped skew cut bits of the key; - A set of tumbler pins (1) and drivers (2) that are spring-biased (3); - a dragging system mechanism ; - the external surface of the rotatable plug, which is in contact with the internal surface of the outer shell, being characterized by the presence of circumferential ridge(s)(5) of any polyangular shape; the internal surface of the outer shell being characterized by circumferential grooves (21) of any polyangular shape, configured to interlock with corresponding symmetrical ridges (5) on the external surface of the rotatable plug ; tumbler pins (1) having wedge-shaped lower tips (24) which come into contact with the key, while their upper surfaces contain a ridge(s) (15) forming a profile(s) configured to interlock with a corresponding groove(s) (19) found on the lower surfaces of their corresponding drivers (2); the interlocking profiles of the grooves and ridges of the pins and drivers having the same profiles as the interlocking circumferential grooves and ridges (21 ;5) found along the surfaces of the outer shell and the rotatable plug, thus creating a geometrical continuity with one another, when, upon insertion of the proper key, each key bitting determines the proper elevational and rotational position of its corresponding pin and driver; The lock being characterised in that : - the cylindrical shaped portion of the key (10) is provided with a plurality of "V'- shaped skew cut bits (12) placed in a "random" dispositioning ( not in linear alignment with one another) along and around its cylindrical surface. - The "V'-shaped skew cut bits differing from one another in: a) their position along the longitudinal axis and around the circumference of the cylindrical portion of the key, b) their varying depth, c) their angular orientation with respect to the longitudinal axis of the cylindrical portion of the key; - the radially-oriented tumbler pin holes (11), housing pins (1) and drivers (2), have a "random" dispositioning within the the rotatable plug and the outer shell in accordance with the placement of the corresponding "V'-shaped skew cut bittings (12) found on the cilindrical portion of the key. - The tumbler pins, that are wedge-shaped at their lower tips (24), being able to fit inside its corresponding "V'-shaped skew cut bits found along the cylindrical surface of the key assuming a position, upon the insertion of a properly bitted key, which complies with each of three conditions imposed by a key bitting: a) its position along the longitudinal axis and around the circumference of the key, b) its varying depth, c) its angular positioning with respect to the longitudinal axis of the key; The three conditions imposed by each "V- shaped key bitting granting a unique elevational and rotational position of each pin/ driver pair that enable the alignment of the ridges and grooves of the pins and drivers (15;19) with the circumferential grooves and ridges (21; 5) found on the surfaces of the outer shell and the rotatable plug. This alignment granting therefore the ability of the rotatable plug to rotate within the outer shell; The insertion of the key is possible from any angular position; The lock is provided with a dragging system mechanism that is able, in the key insertion and extraction phase, to allow the indipendent rotation of the key with respect of the rotatable plug. 2. A lock according to claim 1) wherein the groove(s) found on the outer shell may be conversely found on the rotatable plug, and the ridge(s) found on the rotatable plug may be conversely found on the outer shell, and wherein the tumbler pins whose ridges are designed for continuity with the circumferential ridges on the rotatable plug conversely appear as grooves, and the grooves in the drivers designed for continuity with the circumferential grooves in the outer shell conversely appear as ridges; 3. A lock according to claim 1) and 2) wherein the key has a polyangular shape in cross- section; 4. A lock according to claim 1) and 2) wherein the axial channel ( keyway) into which the key is inserted has a polyangular shape in cross-section; 5. A lock according to claim 1) and 2) wherein the bittings of the key have any polyangular shape; 6. A lock according to claim 1) and 2) wherein the bittings of the key have a curvilinear shape; 7. A lock according to claim 1) and 2) wherein the tumbler pins have, at their tips that make contact with the corresponding key bittings, any polyangular shape; 8. A lock according to claim 1) and 2) wherein the tumbler pins have, at their tips that make contact with the corresponding key bittings , a curvilinear shape; 9. A lock according to claim 1) and 2) wherein the circumferential grooves and ridges found on the outer shell and on the rotatable plug have a curvilinear shape in side- section; 10. A lock according to claim 1) and 2) wherein the surfaces of the pins and drivers designed for interlock with one another are of different shapes in side-section to the surfaces of the rotatable plug and outer shell designed for interlock with one another, but nonetheless provide for continuity between these surfaces and permit the rotatable plug and tumbler pins together to rotate within the outer shell and drivers; 11. A lock according to claim 1) and 2)wherein the interlock configuration(s) between tumbler pins and drivers do(es) not permit their reciprocal axial separation; 12. A lock according to claim 1) and 2) wherein (an) additional element(s) is found between the tumbler pins and drivers having the purpose of creating a hierarchical lock and/ or providing protection from lock manipulation. 13. A lock according to claim 1) wherein the circumferential grooves are exclusively found on the external surface of the rotatable plug or alternatively on the internal surface of the outer shell, while the opposite and interlocking surface (of the outer shell or of the rotatable plug respectively) looks smooth;

Inventors: FICCO STEFANO, FICCO, STEFANO
Applicants: FICCO STEFANO, FICCO, STEFANO
Application year: 1999
Main classification: E05B27
IPC codes: E05B19, E05B27