The present invention refers to an anti-theft device for objects equipped with at least one arm member, particularly for eyeglasses.

WO-A-02061222 of the same Applicant of the present application discloses an anti-theft device for eyeglasses that is the closest prior art for the device of the present application. The device in WO-A-02061222, that features scarce encumbrance, practicality and easy handling, has a wheel for adjusting the grip onto the arm that is accessible for a user and therefore, in particularly difficult environments, could be tampered with tools adapted to force it or to break it.

Object of the present invention is solving the above prior-art problems, by providing an anti- theft device in which the gripping pressure adjusting means onto the arm can be driven by a wheel that can be blocked through sturdy locking means that prevent or make it very difficult to

tamper with it by an unauthorised person.

A further object of the present invention is providing an anti-theft device of the above- mentioned type that has a scarce encumbrance, a light weight, a sturdy seal against thefts and an easy activation by the sales personnel that must place it onto the objects to be protected.

The above and other objects and advantages of the invention, as will appear from the following description, are obtained by an anti-theft device as claimed in Claim 1. Preferred embodiments and non-trivial variations of the present invention are claimed in the dependent Claims.

The present invention will be better described by some preferred embodiments thereof, given as a non-limiting example, with reference to the enclosed drawings, in which:

Figure 1 is a perspective view of an embodiment of the anti-theft device of the present invention;

- Figure 2 is an exploded perspective view of the main components of the anti-theft device of Fig. 1;

- Figure 3 is a sectional perspective view of the anti-theft device of Fig. 1;

- Figure 4 is a side sectional view of the anti-theft device of Fig. 1 in a closed position;

- Figure 5 is a side sectional view of the anti-theft device of Fig. 1 in an open position;

- Figure 6 is a perspective cut-away view that better shows the arrangements of the main components of the device of Fig. 1; and

- Figures 7 and 8 are two perspective views similar to Fig. 1, that show two other construction variations of the device of the invention.

With reference to the Figures, preferred embodiments of the anti-theft device of the present invention are shown and described. It will be immediately obvious to the skilled people in the art that numerous variations and modifications (for example related to shape, sizes and parts with equivalent functionality) could be made to the described device without departing from the scope of the invention as claimed in the enclosed claims.

The Figures show the anti-theft device 1 of the present invention in its most common application for protecting eyeglasses (not shown) . It will be immediately obvious to the skilled people in the art that such device 1 can be applied with a like efficiency to any item equipped with

elongated members, arm members, etc., whose protection is needed.

With reference to the Figures, the anti-theft device 1 for objects equipped with at least one arm member (not shown) , particularly for eyeglasses, comprises:

- tightening means 10, 11, 12, 13, 14 of the arm member, in which such tightening means 10, 11, 12, 13, 14 are adapted to assume an open position in which they receive therein or free therefrom the arm member and a closed position in which they are immovably tightened against the arm member;

control means 2 of the tightening means 10, 11,

12, 13, 14, in which such control means 2 are adapted to move the tightening means 10, 11, 12,

13, 14 between their two opening and closing positions;

containing means 3 that contain therein anti- theft means (not shown) ;

- engaging means 5, in which the engaging means 5 allow an operating connection between the control means 2 and the tightening means 10, 11, 12, 13, 14; and

locking and unlocking means 6, 7, in which the locking and unlocking means 6, 7 in a first position are adapted not to engage the control means 2 by assuming a locking position in which the engaging means 5 and the tightening means

10, 11, 12, 13, 14 are not operatively connected to the control means 2, while the locking and unlocking means 6, 7 in a second position are adapted to engage the control means 2 by assuming an unlocking position in which the engaging means 5 and the tightening means 10,

11, 12, 13, 14 are operatively connected to the control means 2.

In particular, in the preferred, but not limiting, embodiment shown, the tightening means 10, 11, 12, 13, 14 are composed of a lower body 10, 11 supporting at least one lower plate 13 and an upper pin 12 supporting at least one upper plate 14, one (13 in the Figures) of the plates 13, 14 being fixed and another one (14 in the Figures) of the plates 13, 14 being movable approaching and going away to and from the fixed plate 13 respectively for tightening and freeing the arm member between them.

Further in particular, each one of the plates

13, 14 is wholly composed of or is equipped with at least one layer of rubber adapted to improve a grip onto the arm member to be tightened.

As can be seen in the Figures, the upper pin 12 is further equipped with a projection 15 for an operating connection to the engaging means 5, as will also be described below.

According to the shown embodiment, moreover, the control means 2 are composed of a wheel equipped with grasping grooves 20, in which the wheel 2 is adapted to house therein both the engaging means 5 and the locking and unlocking means 6, 7, to allow a greater compactness and sturdiness for the device 1.

In order to better perform their function, the engaging means 5 can be composed of at least one threaded stud bolt adapted to slide into threadings obtained into the lower body 10, 11 and adapted to be operatively connected to the projection 15 in order to perform the tightening and freeing positions of the arm member.

Still preferably, the locking and unlocking means 6, 7 are composed of at least one gear-shaped pin 6 operatively connected to at least one, suitably shaped nail 7 to perform a lifting and

lowering movement along a longitudinal axis of the device 1. The gear-shaped pin 6, that is integral with the engaging means 5 (through the engagement between the teeth of the gear-shaped pin 6 and the grooves of the engaging means 5, as can be better seen in Fig. 6) is adapted to cooperate with or be detached from the upper grooved part of the control means 2 (through engagement in the grooves 25) , to allow or prevent an engagement of the control means 2 themselves with the tightening means 10, 11, 12, 13, 14.

Moreover, the containing means 3 are composed of a ring-shaped body containing the anti-theft means, which are commonly composed of at least one electric wire that is spirally wound (of the radio- frequency type) and is adapted to activate theft- detecting means (not shown) upon passing inside a magnetic field generated by the theft-detecting means, an activation of the theft-detecting means in turn activating acoustic or light signalling means (not shown) , that are common in premises where this type of global anti-theft system is installed.

Figures 7 and 8, instead, show two further possible variations of the device 1 described

above: the only differences with respect to what has been described before are given by . the configurations of the containing means 3, that, in the embodiment shown in Fig. 7, are composed of an elongated box-shaped body adapted to contain anti- theft means of a magneto-acoustic or an electromagnetic type (commonly shaped as an elongated strip) , while, in the embodiment shown in Fig. 8, they are composed of a box-shaped body that is shorter than the previous one, and is adapted to contain anti-theft means of a magneto-acoustic or radio-frequency type with cylindrical configuration with a wire wound thereon.

With reference now to Figures 4 and 5, the two operating steps will be described to detach the anti-theft device 1 from the eyeglasses; it is obvious that, by suitably reversing the steps, the attachment of the device 1 to the arm of the eyeglasses to be protected can be performed.

Fig. 4 shows the closure position, in which the nail 7 is inserted into the wheel 2, which latter one "idly" rotates and does not allow any movement of the device 1, since there is no meshing between the upper grooved part 25 of the wheel 2 and the gear-shaped pin 6 (that is integral with

the nail 7) and is meshing- with the engaging means 5.

Fig. 5,. instead, shows that, when the nail 7 is attracted upwards (as seen in the Figure) (for example through external attraction means of the magnetic type, not shown) , also the gear-shaped pin 6 is attracted upwards, the upper part of the pin 6 coming now to engage the grooves 25 of the wheel 2 in such a way that, when the wheel 2 itself is rotated, the whole nail 7 - pin 6 - stud bolt 5 assembly rotates, and therefore the movable pin 12 is lifted and is moved away from the fixed body 10, 11, thereby allowing to enlarge or narrow the ^■ space available for inserting or removing the eyeglasses arm and then tighten the device 1, after its possible insertion.

The nail 7 remains in a lifted position due to its particular configuration, in which one part of its elongated body is enlarged and has a greater diameter, in order to engage suitable holding tongues 23 (preferably provided in a number equal to three or four, but also as a circular crown) of the wheel 2, that keep the nail 7 in its lifted position preventing it from going back into the wheel 2. Only when on the nail 7 (for example with

the fingers of a hand) a pressure is exerted that is enough to make it win the resistance of the tongues 23, it is enable to go back into the wheel 2, where it remains inserted, again due to its partially enlarged configuration that abuts against the tongues 23, this time in order to keep it inside the wheel 2 till its following magnetic attraction outwards.

Obviously, through a suitable configuration of the holding values of the tongues 23 and the magnetic force values of the external magnetic means, an undesired removal of the nail 7 from the wheel 2 by using common magnets can be prevented.