The present invention relates to a glazing shattering device, which in general is intended to break one or more panes made of glass, or of similar shatterable material, which implement the glazing, and then it is used, for example, to shatter the glazing of windows and portholes of vehicles such as trains or buses, or windows of palaces with the purpose of guaranteeing, in case of emergency, a way out for evacuating people or a passage for air.

Generally, a glazing shattering device substantially comprises at least a hammer provided with at least a ferrule, usually made of stainless steel, or made of very hard ceramic material, placed at one end of the hammer of said hammer head, which can assume several shapes. The most common shape provides that the hammer has a "T"-like shape with two ferrules each one placed on the side ends of the hammer head.

Currently, the glazing shattering devices which are available onboard vehicles can be manual, that is real hammers which are inserted in a respective seat at sight, therefrom they can be collected, after having broken a seal, even by unskilled personnel, to hit the glazing of a nearer window, or however a window more suitable to create an escape path.

To increase the chances of the manoeuvre being successful, on the glass panes onboard the vehicles indications are provided about which glazing is the most suitable to create an escape route, and often also the point on which one must hit is indicated, studied to implement a complete destruction of the glazing.

However, the use of these hammers often depends upon the initiative and lucidity of people even untrained to intervene in a similar event, thus causing uncomplete shattering, in case of glazing's which are the less suitable to create an escape route, and with timing which depends upon the excitement of the moment and then which could be delayed or anticipated with respect to the optimal moment .

These difficulties are aggravated by the fact that the seats in which the hammers are arranged, are not often at hand, even to avoid an improper use thereof, in inappropriate situations or in real vandalism: this forces the untrained personnel or the passengers themselves to do a frantic search for the tool with which a glazing can be shattered .

To obviate to these objective drawbacks, devices operating automatically have been proposed, which are already arranged in close proximity to the glazing to be shattered, in a suitable position, at least a hammer being actuated by an actuator, with a snap operation and with a predetermined force, then planned to be able to be actuated in simpler and safer way, to implement a shattering of the glazing .

An example of glazing shattering device of this type is described in the British patent Nr. GB 2,396,651 A, wherein a hammer head is revolvingly assembled on a frame and it is pushed by a linear actuator, actuated by a preloaded spring which provides the force required for the wished shattering .

However, once actuated, in the glazing shattering device it is not provided that the hammer head returns in an operating position, and then the device cannot be re actuated if, due to some positioning defect or defect in calculating the force, a second attempt is required.

In other words, the operation of this device is irreversible and produces one single impact with the glass pane: to make the device to operate again, complex maintenance procedures are required, which can be performed by specialized personnel.

This problem is felt above all when the hammer acts on the edge of the glass instead of on its flat surface: in this case often the hammer causes a partial shattering of the glazing, with a propagation of cracks, and then the people near the glazing have to assume the task of shattering the glazing .

In fact, it is impossible to provide that the ferrule assembled in the device could shatter a respective pane of the glass with several hits rather than one hit only, and a wrong, unvoluntary or inappropriate use of the device would surely cause the partial and in case unwished shattering of the pane, but in case not a complete shattering .

The technical problem underlying the present invention is to provide a glazing shattering device and a safety system allowing to obviate the drawbacks mentioned with reference to the known art.

Such problem is solved by a glazing shattering device as specified above and as defined in the enclosed independent claims .

In particular, the glazing shattering device according to the invention comprises a supporting frame which can be shaped like a casing, which in turn has an open side which is apt to be positioned facing towards the glass pane to be broken, so that the mechanisms inside thereof cannot be reached .

Moreover, the device is provided least with a hammer having a hammer head with at least a ferrule, made of suitable material, to shattering a respective glass pane; the hammer is hinged in said supporting frame thereby it is movable between a respective rest position, in which said at least a ferrule is spaced apart from its target glass pane, and an impact position, in which said at least a ferrule interferes with said glass pane. It can be provided that the ferrule impacts the target glass pane at an edge thereof, in one or more points of such edge, and it can even be provided that one single hammer is arranged to impact against the edge of several glass panes simultaneously.

The hammer even comprises a preloaded elastic element, which keeps it in said rest position, when it is not stressed.

The device, at last, comprises a linear actuator which is inserted in said casing including it completely, and which can be actuated by any actuation control arranged outside the casing or on the casing itself, for example a button or a lever suitably highlighted and provided with a seal hindering its inappropriate use.

It is further to be meant that the operation control can include a signal sent remotely, in case even automatically, when predetermined conditions occur, without requiring the intervention of personnel on site.

The linear actuator preferably comprises a piston head which is snap movable between a respective rest position, in which it does not interfere with said at least a hammer, and a break position, in which said piston head pushes one or more hammers simultaneously through said open side in said break position, wherein a mechanism for returning the piston head in said respective rest position is provided.

The motion of the hammer or of the hammers by the linear actuator causes the impact between the hammer head, and in particular of the ferrule on it, with the respective target pane but, when the stress ceases, upon the piston head returning in its own rest position, the hammer head too returns in its rest position, and then it is ready for a new actuation.

In other words, the operation of the glazing shattering device is reversible. In this way, the actuation control of the linear actuator can provide that it implements not only one single stroke of the piston head, but several strokes, that is several stresses which produce as many impacts of the hammer head on the respective glass pane, but in an even very short time range.

Or, should the first impact be not successful, it is possible to perform immediately a new attempt.

The glazing shattering device as defined above is suitable to be placed in the framework of the fixture, that is of a fixture frame supporting the glazing, said open side facing towards a side edge of the glazing.

Said glazing shattering device may belong to a wider safety system, comprising a plurality of glazing shattering devices and an alarm system, as well as with a control unit which, based upon the received alarm signals, activates the linear actuators of the glazing shattering devices involved by the alarm.

The main advantage of the glazing shattering device and of the safety system defined above consists in the reversibility of their operation, which allows to repeat the impact or to plan several impacts in a selected number of devices connected to the safety system.

The present invention will be described hereinafter according to a preferred embodiment example thereof by way of example and not with limitative purposes with reference to the enclosed drawings wherein:

* figure 1 shows an axonometric view of the glazing shattering device according to the invention, an exploded view near a glazing;

* figure 2 shows an axonometric view of the glazing shattering device of figure 1 in an operating configuration, wherein the device is enlarged for better visibility;

* figure 3 shows an enlarged axonometric view of a detail of the glazing shattering device of figure 1; * figure 4 shows a side view of the glazing shattering device of figure 1 in a section making visible the inside of its casing; and

* figure 5 shows a schematic representation of a safety system using a plurality of glazing shattering devices.

With reference to figures 1 to 4, a glazing shattering device is designated as a whole with 10, positioned near a glazing 1 belonging to a window structure, that is a glass wall, a window or porthole, provided with a respective fixture frame 6 comprising a framework represented schematically and designated with 5 (figure 1), which in turn includes a supporting frame of the glazing shattering device 10, formed inside thereof.

The supporting frame comprises a fastening stirrup 4 and at least a hammer 2 connected to the stirrup 4 in the way which will be described hereinafter. The frame further includes a linear actuator, designated with 3, arranged for actuating at least a hammer 2, or for actuating simultaneously several hammers, in particular at least two hammers, each one intended to shatter a respective glass pane.

To this purpose, the glazing 1 of the present application example of the herein described glazing shattering device 10 is formed by one or more glass panes, or equivalent material as long as it is shatterable; in the present example, the glazing 1 comprises a pair of glass panes 7, separated by an intermediate cavity and kept in a position spaced apart therebetween by the fixture frame 6.

Figure 2 illustrates the position of the glazing shattering device 10 with respect to the glazing 1: it is positioned at a framework tract of the fixture frame, so that the supporting frame of the device and the framework implement a casing surrounding the hammer 2 on three sides, by leaving an open side which is facing towards the glazing to be shattered. In particular, the glazing shattering device 10 is positioned so as to act not on the flat surface of the glazing 1, but on the edge of each one of the panes 7 even if, in other embodiments, in particular those intended for glazing's with one single pane, it could act on the flat surface of one pane, in case near its edge.

According to this preferred embodiment example, the glazing shattering device 10 comprises one single hammer 2 for each respective glass pane 7 composing the glazing 1, but it is meant that the invention relates to other solutions using one single hammer for several panes, or several hammers for each pane.

Therefore, the present embodiment example provides the presence of a pair of hammers 2 placed side by side, revolvingly connected to the fastening stirrup 4 del supporting frame.

The hammer 2 comprises a tilting body 8 hinged to a supporting element 9 which in turn is fastened to the supporting frame of the device at said fastening stirrup 4; in this way, the hammer 2 is hinged to the supporting frame of the glazing shattering device 10.

It is to be noted that the supporting element 9 comprises a pair of hammer seats, each one for one single hammer 2.

The hammer 2 further comprises a hammer head 11 formed at an end of the tilting body 8, comprising one or more ferrules 12. In this embodiment example, the hammer head 11 comprises a respective ferrule 12, made of steel or another material with high hardness, such as a ceramic material .

More than one ferrule for one single glass pane may be provided, that is more than one ferrule for one single hammer, or one single hammer comprising several ferrules staggered therebetween, to hit simultaneously, with one single motion of the single hammer, several glass panes of a glazing 1. Each ferrule 12 is positioned on the respective hammer head 11 so that, when the tilting body is rotated, it impacts on the target glass pane 7 at its edge.

Each hammer 2 is then movable between a respective rest position, in which the tilting body 8 is positioned substantially vertically and wherein the ferrules 12 are spaced apart from the respective glass pane and generally, from the glazing 1, to a break position, in which said ferrules interfere in impact with the respective glass pane 7.

The supporting element 9, which implements an assembly counter-stirrup, comprises a pin 13 which implements said hinge and which crosses said hammer seats; at such pin 13, each hammer 2 comprises a preloaded elastic element 14, in particular a torsion spring wound around the pin 14, having an end in contact with the tilting body 8 so that the hammer, if it is not stressed, is kept in the rest position.

The supporting element 9 further comprises a counterpart surface 15, opposite to the hammer seats, which is apt to be rested upon the edge of the glass panes 7.

The glazing shattering device 10 comprises, inside the casing formed in the supporting frame, a linear actuator 3, which in the present embodiment example is of electromagnetic type, but which can even be pneumatic or hydraulic.

To this purpose, it may include an electric connection to an electricity network, or a battery, in case rechargeable and connected to an electricity network, in order to be able to actuate the actuator 3 even in absence of power supply.

In case of pneumatic actuator, it can be connected to a hydraulic circuit under pressure of the vehicle.

The actuator 3 comprises a cylinder 16 including a piston, therefrom a piston head 17 projects; the piston head 17 is snap movable between a respective retracted rest position, in which it does not interfere with the above-described hammers 2, to a break position, or position interfering with the hammers 2, in which said piston head 16 pushes each hammer through said open side in said break position, by hitting the hammer head 11 which, to this purpose, has a rounded surface.

In the linear actuator 3 a mechanism for returning the piston head 17 in said respective retracted position is provided. The return mechanism can have a mechanical nature, for example a spring inside the actuator which brings the piston back to its starting position, or an electromagnetic, or hydraulic, position.

The piston head 17 then follows a rectilinear route, wholly incorporated in the casing of the glazing shattering device 10, which interferes with the hammer or hammers 2, by determining the rotation thereof. To guide the piston head 17, and avoid possible misalignments, a linear guide may be provided.

The linear actuator 3 can be actuated by acting on an actuation control arranged outside the casing of the supporting frame or on the casing itself, or substantially on or near the framework 6 delimiting the glazing.

The actuation control can consist, for example, of a button or a lever suitably highlighted and provided with a seal hindering the inappropriate use thereof.

Moreover, it is to be meant that the actuation control can include a signal sent remotely, in case even automatically, when predetermined conditions occur, without requiring the intervention of personnel on site.

The above-described glazing shattering device 10 then can generate the shattering of a glazing without the intervention of personnel. In fact, once actuated, it determines an impact with the glass panes composing the glazing, by consequently generating a crack which causes the shattering thereof. In this way, the subjective factor linked to the person intervening to break the glazing is removed. Moreover, since the device 10 is inside the window frame, it acts instantaneously, once activated, by removing the periods of time required to identify the hammer position, to break the seal and to go in front of the glazing to be shattered, and to identify the point having greater fragility.

An additional advantage is determined by the assembly inside the window framework, and preferably at an area having greater fragility, so as to ease the triggering of the crack and to speed up the glazing shattering.

Preferably, the glazing shattering device 10 is used in a safety system 100 comprising a system for generating alarms 101, or alarm signals which are routed through a control unit 102 which, when determined conditions occur, can emit an actuation signal for one or more glazing shattering devices 10.

Advantageously, the actuation signal can be transmitted, for example, through a switch placed near the windows of the transportation means, preferably with a safety cover preventing the improper use thereof.

The safety system 100 then can include a plurality of glazing shattering devices 10, linked to one single control unit 102.

Advantageously, said safety system 100 can be wholly automated, for example it could provide sensors capable of detecting accidents, or the presence of fires and through an electric circuit, thereto the control unit 102 belongs, it could activate the linear actuator 3. In this way, the safety system 100 is wholly autonomous from the human intervention and it becomes suitable to be used even in case of unconsciousness of passengers.

An additional possible solution could provide the activation remotely, wherein only the driver or some operators responsible for the means can activate one or more glazing shattering device 10.

Advantageously, the control unit 102 allows an analysis of the received actuation signals, based thereupon the glazing shattering devices 1 are or are not activated, so as to avoid useless shattering, as in case of improper use of the glazing shattering devices 1 currently present in the transportation means. To the above-described glazing shattering device and safety system a person skilled in the art, with the purpose of satisfying additional and contingent needs, could bring several additional modifications and variants, all however comprised within the protective scope of the present invention, as defined by the enclosed claims.