Patent Description:
The art of keys and cylinders for locks calls for ever increasing security. The shape of the key is the first barrier that impedes the insertion of a non-authorized key into the cylinder of a lock. Insofar as the space within the lock that is able to accommodate the key is finite, such space has to be specially structured in order to allow for the maximum number of unique key shapes, namely encodings, so as to be able to develop a system of conjugate key/cylinder profiles of adequate size and complexity.

A new system of conjugate key/cylinder profiles must furthermore be different from previous systems in such a way that the encoding may be exclusive to the manufacturer and the final user may benefit from the security offered by such exclusivity.

Furthermore, the new key system must ensure optimal sliding of the key within the relative lock and must ensure the most correct positioning thereof in relation to the pin combinations (the encoding reading elements obtained on the key).

A reversible key system according to the preamble of claim <NUM> is known from <CIT>. Other reversible key systems are disclosed in <CIT> and <CIT>.

The object of the present invention is that of supplying a new key profiles system that resolves the problems of the known art and that satisfies the requirements of the sector for a reversible key, that is to say provided with a symmetrically rotated profile so that it may also be inserted into the lock when rotated by <NUM> degrees.

This purpose is achieved by means of a key system according to claim <NUM>. The dependent claims describe preferred embodiments of the invention.

The features and advantages of the key system according to the present invention will appear more clearly from the following description, given as a nonlimiting example according to the appended figures, wherein:.

The key/cylinder system according to the present invention comprises a plurality of keys <NUM> and a plurality of cylinders <NUM>.

The key <NUM>, object of the present invention, is a reversible key insofar as it is provided with a symmetrically rotatable profile, in such a way that it may also be inserted into a lock when rotated by <NUM> degrees (<FIG>). In fact, reversible keys, contrary to traditional keys, may be inserted into a lock from both sides, that is to say independently of the insertion orientation. The key <NUM> is also called a "horizontal key" insofar as it is horizontally inserted in relation to the lock <NUM>.

The key/cylinder system according to the present invention comprises a cylinder <NUM> that is part of a lock assembly <NUM> comprising a cylinder housing that supports, in a rotating manner, the cylinder <NUM> itself, and that includes, for example, pins, sliders and other mechanisms that are adapted to impede the rotation of the cylinder up and until an appropriately configured key <NUM> is inserted therewithin in order to actuate the lock <NUM>.

The key <NUM> comprises a grip <NUM> and a body <NUM>, called a pen, that is intended to be inserted, at least partially, into the cylinder <NUM> of a lock <NUM> in order to allow for the opening of the same.

The body <NUM> comprises, in proximity to the grip <NUM>, a stop <NUM> that is substantially in the form of a step and that acts as an end stop in order to limit any further insertion of the body <NUM> of the key <NUM> into the lock.

The body <NUM> comprises, starting from the stop <NUM>, a side <NUM> that is intended to be incised in order to obtain the encoding of the key <NUM>. In the case of reversible keys the encoding is obtained upon both the side <NUM> and upon the face <NUM>, and upon the mirror side and face. In the case of reversible keys the encoding is obtained by means of blind encoding holes of a varying depth, wherewith the pins of the lock assembly interact in order to obtain the combination. In the present case, the encoding holes are obtained on the backing body <NUM>.

The body <NUM> comprises a key profile <NUM> corresponding to the cross-section of the body <NUM> shown for example, in <FIG>. The key profile <NUM> allows for the pass/no-pass function of the key <NUM> within the cylinder <NUM> of the lock. Preferably, the key profile <NUM>, that is to say the cross-section of the key <NUM>, has a length A of about <NUM> and a height B of about <NUM>.

The key profile <NUM> comprises a series of longitudinal grooves that form the guide (pass/no pass) for the insertion of the key <NUM> into the lock <NUM>. The longitudinal grooves <NUM>,<NUM>,<NUM> extend for the entire portion of the body <NUM>.

The body <NUM> comprises a face <NUM> with encoding that is defined by the longitudinal grooves <NUM>,<NUM>,<NUM>, that translates to an encoded side <NUM> of the key profile <NUM>.

The body <NUM> comprises an opposite face <NUM> with an encoding that is defined by the longitudinal grooves <NUM>,<NUM>,<NUM>, which translates to an opposite encoded side <NUM> of the key profile <NUM>.

The centerline of the body <NUM> defines the axis Y, that is to say the axis that longitudinally divides in half the cross-section of the key <NUM>, and C defines the center of the centerline axis Y, as in <FIG>. The encoding of the opposite face <NUM> is the same as that of the face <NUM>, but rotated by <NUM>° in relation to the center C of the centerline axis Y. In other words, the encoding of the opposite face <NUM> is the same as that of the face <NUM>, but symmetrical in relation to the Y axis and flipped over from left to right. Therefore, insofar as the encoding of the opposite face <NUM> (encoded opposite side <NUM>) is the same as that of the face <NUM> (encoded side <NUM>), for simplicity only the encoding of the face <NUM> will be described in detail.

The encoded side <NUM> comprises three longitudinal grooves <NUM>,<NUM>,<NUM> that are always present within the series of keys of the system according to the present invention. Advantageously, the presence of three grooves ensures the correct planar positioning of the key <NUM> within the lock <NUM>, making it possible to obtain smooth rotation of the key itself. Each groove, in fact, represents a pushing point of the key rotating within the cylinder of the lock <NUM>.

The grooves <NUM>,<NUM>,<NUM> have substantially triangular sections, with a rounded vertex V.

Preferably, the angle of inclination of the hypotenuse is the same for all three of the grooves <NUM>,<NUM>,<NUM>.

At least one pair of grooves has a right-angled triangle profile. The grooves are oriented in such a way as to be facing one another in correspondence with the vertical sides of the triangles, in such a way that the hypotenuses i converge towards the centerline axis Y. In accordance with the invention, the grooves define therebetween a centering tooth <NUM>, of a substantially square or rectangular section, and of a parallelepiped shape. Advantageously, the presence of the centering tooth <NUM>, on both of the faces <NUM>,<NUM> of the key <NUM>, helps with the centering of the key within the lock, by rendering the insertion of the key into the lock particularly smooth.

Preferably, the centering tooth has a width L of about <NUM>.

The grooves are preferably oriented in such a way that the respective hypotenuses i define converging planes <NUM> arranged on the sides of the centering tooth <NUM>. Advantageously, the presence of planes that converge at the sides of the centering tooth <NUM> helps with the auto-centering of the key within the lock. Advantageously, furthermore, the presence of converging planes reduces the risks of tampering insofar as it impedes any break-in tools from correctly reaching the rotation mechanism of the cylinder <NUM>. Said diligence renders any manipulation of the cylinder by means of lock picks more difficult.

Advantageously, the fact that the encoding of the opposite face <NUM> is the same as that of the face <NUM>, but symmetrical and flipped from left to right, renders the structure well balanced, with a centering tooth on each face <NUM>,<NUM>, which contributes to the auto-centering of the key within the lock.

Preferably, at least one pair of grooves has a triangular profile. In this example, the grooves are oriented in such a way as to be facing one another in correspondence with the hypotenuses i. The grooves define therebetween a backing body <NUM> with a substantially trapezoidal section having the larger base towards the centerline. The backing body <NUM> helps with the correct positioning of the body <NUM> (male) of the key in relation to the profile (female) of the cylinder <NUM> of the lock. Given that, upon the backing body <NUM>, encoding holes are made that interact with the combination pins, it is essential that the backing body may be correctly aligned in relation to the row of pins of the lock.

Preferably, the backing body <NUM> has a greater width than that of the centering tooth <NUM>.

Preferably, the backing body <NUM> that is present on one face <NUM>,<NUM> of the key <NUM>, is aligned with the centering tooth <NUM> that is present on the opposite face <NUM>,<NUM>.

The grooves <NUM>,<NUM>,<NUM> are of a varying depth in the series of keys of the system according to the present invention. Preferably, in the series of keys, the grooves have three different levels of depth and in particular a maximum depth, an intermediate depth, and a minimum depth. Advantageously, the presence of grooves of a varying depth makes it possible to define a pass/no-pass code that allows to insert, or not, one of the keys <NUM> of the series of keys into one or more cylinders <NUM> of the series of cylinders of the key/cylinder system according to the present invention.

Preferably, at least one of the grooves has such a depth as to reach the centerline axis Y. In this embodiment variant the profile of the key is paracentric, insofar as the grooves touch or cross, at least twice (groove on the face <NUM> and groove on the opposite face <NUM>), the central axis (or centerline axis Y) of the key <NUM>. This technical solution renders any manipulation of the cylinder <NUM> by means of lock picks more difficult.

As a reference for the description, the profile keys are described starting from the lowered edge <NUM>, which is identifiable insofar as the face <NUM>,<NUM> of the key within that area has a height that is lower in relation to the rest of the plane. Preferably, the lowered edge <NUM> is lowered by about <NUM> in relation to the rest of the plane of the face <NUM>,<NUM> of the key <NUM>.

The grooves are, starting from the lowered edge <NUM>: first groove <NUM>, second groove <NUM>, third groove <NUM>. The second groove <NUM> is the central groove.

The table reported below indicates, for each of the grooves <NUM>,<NUM>,<NUM>, the preferred depth values, wherein H1 is the depth of the first groove <NUM>, H2 is the depth of the second groove <NUM>, and H3 is the depth of the third groove <NUM>.

Preferably, the second groove <NUM>, or the central groove, has such a depth as to reach the centerline axis Y, as in <FIG> and <FIG>.

Preferably, the first groove <NUM> has a right-angled triangle section, wherein the hypotenuse is inclined by an angle α1 of about <NUM>°.

Preferably, the second groove <NUM> has a right-angled triangle section, wherein the hypotenuse is inclined by an angle α2 of about <NUM>°.

Preferably, the third groove <NUM> has a right-angled triangle section, wherein the hypotenuse is inclined by an angle α3 of about <NUM>° in relation to the vertical, and the short side is inclined by and angle α4 of about <NUM>° in relation to the vertical.

Preferably, the first groove <NUM> and the second groove <NUM> have a right-angled triangle profile. In this example, the first groove <NUM> and the second groove <NUM> are oriented so as to be facing one another in correspondence with the vertical sides of the triangles, in such a way that the hypotenuses i converge towards the centerline axis Y. In this example, the first groove <NUM> and the second groove <NUM> define therebetween a centering tooth <NUM>, of a substantially square or rectangular section, and of a parallelepiped shape. Furthermore, the first groove <NUM> and the second groove <NUM> define, by means of the respective hypotenuses i thereof, converging planes <NUM> arranged at the sides of the centering tooth <NUM>.

Preferably, the second groove <NUM> and the third groove <NUM> are oriented so as to be facing one another in correspondence with the respective hypotenuses i which thereby converge towards the exterior of the body <NUM>. The second groove <NUM> and the third groove <NUM> define therebetween a backing body <NUM> with a substantially trapezoidal section having a larger base towards the centerline.

The same encoding that is adopted for the key <NUM> is obtained in the cylinder <NUM> of the lock. The cylinder <NUM> therefore comprises a seat <NUM>, wherein the body <NUM> of the key <NUM> is inserted, having a cylinder profile <NUM> (shown, for example, in <FIG>) with the same encoding as that of the key profile <NUM>.

The seat <NUM> therefore comprises a profile that is defined by three ridges having the same characteristics as those of the respective grooves of the key <NUM>. The ridges, starting from the area in which the lowered edge <NUM> of the key is located, are: first ridge <NUM>, second ridge <NUM>, third ridge <NUM>. Thus, in the same way as the grooves have a varying depth, the ridges have a varying height in the series of cylinders of the system according to the present invention.

The ridges <NUM>,<NUM>,<NUM> have a substantially triangular section, with a rounded vertex V.

Preferably, the angle of inclination of the hypotenuse is the same for all three ridges.

Preferably, at least one pair of ridges has a right-angled triangle profile. In this example, the ridges are oriented such as to be facing one another in correspondence with the vertical sides of the triangles, in such a way that the hypotenuses i converge towards the interior of the seat <NUM>. In this example, the ridges define therebetween a centering recess of a substantially square or rectangular section. In this example, the ridges are oriented in such a way that the respective hypotenuses define converging planes arranged on the sides of the centering recess.

Preferably, at least one pair of ridges has a triangular profile. In this example, the ridges are oriented in such a way as to be facing one another in correspondence with the hypotenuses. The ridges define therebetween a backing recess with a substantially trapezoidal section having a larger base facing the interior of the seat <NUM>.

Preferably, the backing recess, arranged on one side of the seat <NUM>, is aligned with the centering recess arranged on the opposite side of the seat <NUM>.

In the series of cylinders <NUM> of the system according to the present invention the ridges <NUM>,<NUM>,<NUM> have a varying height. Preferably, the ridges have three different height levels and in particular a maximum height, an intermediate height, and a minimum height.

In summary therefore, the reversible key system according to the present invention comprises:.

The invention also relates to a key/cylinder system for locks comprising:.

Furthermore, the key/cylinder system comprises at least one master key, insertable into all of the cylinders <NUM> of the series, wherein all three thereof have the grooves <NUM>,<NUM>,<NUM> with the maximum level of depth.

Innovatively, a key system according to the present invention is easy to use, safe and particularly effective.

Advantageously, the key system according to the present invention ensures optimal insertion of the key into the relative lock.

Advantageously, the reversible key system permits insertion into the lock on both sides, and offers greater comfort, above all under poor lighting conditions or for visually impaired people.

Advantageously, furthermore, the system of profiles according to the present invention makes it possible to obtain large scale master key systems, exploiting the existence of key profiles that are suitable for use in multiple cylinder/lock profiles and vice versa. One practical usage example may be a large hotel where it is necessary to supply single keys for guest rooms and differing levels of master keys for service personnel. It is possible to dedicate a profile to each floor of the hotel, with a relative floor master key for the cleaning staff of the floor itself, and a master key for the security staff with such a profile that it may be inserted into every cylinder of every floor.

Claim 1:
A reversible key system for locks, comprising a series of reversible keys (<NUM>), each key (<NUM>) having:
- a body (<NUM>) provided with a grip (<NUM>), said body (<NUM>) having a face (<NUM>) and an opposite face (<NUM>), and a cross-section;
- wherein the cross-section of the body (<NUM>) has a key profile (<NUM>) defined by:
-- an encoded side (<NUM>) obtained on the face (<NUM>), having three longitudinal grooves (<NUM>,<NUM>,<NUM>), all triangular in shape, each having a varying depth in the series of keys (<NUM>);
-- an opposite encoded side (<NUM>) obtained on the opposite face (<NUM>), equal to the encoded side (<NUM>) but rotated by <NUM>°,
characterized in that two of the three grooves (<NUM>,<NUM>,<NUM>) define a centering tooth (<NUM>) with a square or rectangular section.