Patent Publication Number: US-2021190128-A1

Title: Safety device

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention concerns a safety device designed to cover an element or a hole which needs to be placed in a safe condition. More specifically, the present invention concerns a safety device which makes it possible to cover an element or a hole that needs to be placed in a safe condition with a safety cover that can be removed by moving it according to a predetermined combination. 
     STATE OF THE ART 
     In different fields of application it is often necessary to cover elements which need to be placed in a safe condition, in such a way that they can be accessed exclusively by authorized operators/users. 
     By way of example, an element which needs to be placed in a safe condition may be a locking bolt or nut of a car or motorbike wheel rim. As an alternative, the element which needs to be placed in a safe condition may be the filler cap of a car or a motorbike. As another alternative, the element which needs to be placed in a safe condition may be a bolt, a nut, a button of a device. As another alternative, the element which needs to be placed in a safe condition may be a hole or a cavity such as, for example, the hole of the filler cap of a car or a motorbike, or an electric outlet, etc. More generally, the element which needs to be placed in a safe condition may be any element that must not be rotated, pushed, removed, accessed, etc. by unauthorized operators/users. 
     The invention allows such an element to be placed in a safe condition by means of a safety device that, through a safety cover, covers the element in such a way as to prevent access to the latter unless the safety cover is removed. The removal of the safety cover requires that the latter be moved according to a predetermined combination and thus allows said element to be accessed exclusively by the staff who knows the combination. 
     An embodiment of the invention may refer to a safety device designed to cover an element or a hole which needs to be placed in a safe condition, wherein the safety device comprises: a coded body, a safety cover, a first locking element and a second locking element positioned between the coded body and the safety cover, wherein the coded body comprises a first contact surface and a second contact surface, wherein the first locking element comprises a first abutting element configured in such a way that it abuts the first contact surface, wherein the second locking element comprises a second abutting element configured in such a way that it abuts the second contact surface, and wherein the first contact surface is not coplanar with the second contact  20  surface. 
     In some embodiments, the coded body may comprise a third contact surface and a fourth contact surface, wherein the third contact surface may not be coplanar with the fourth contact surface. 
     In some embodiments, the first abutting element may be longer than the second abutting element. 
     In some embodiments, the coded body may comprise a coding cavity inside which the first abutting element and the second abutting element can be at least partially positioned. 
     In some embodiments, the coding cavity can be included between the first contact surface and the third contact surface and between the second contact surface and the fourth contact surface. 
     In some embodiments, the coded body may comprise a release cavity connected with the coding cavity, through which the first abutting element and/or the second abutting element can pass. 
     In some embodiments, the safety cover may be provided with grooves. 
     In some embodiments, the distance between the first contact surface and the release cavity, and/or the distance between the second contact surface and the release cavity may depend on the position of the grooves, and may be preferably equal to the angular dimension of, a plurality of grooves, even more preferably equal to a multiple of the angular dimension of one of the grooves. 
     In some embodiments, the safety cover may comprise a first seat for the first locking element and a second seat for the second locking element. In some embodiments, the first locking element may comprise a first body, the first body may describe a first plane, wherein the first abutting element may be inclined with respect to the first plane. 
     In some embodiments, the coded body may comprise a first abutting ring and a second abutting ring, wherein the first abutting ring may comprise the first contact surface, wherein the second abutting ring may comprise the second contact surface, wherein the first abutting ring and the second abutting ring can be movable with respect to each other in a coding position of the coded body and can be fixed with respect to each other in a locking position of the coded body. 
     In some embodiments, the coded body may comprise a plurality of locking rings among which there are the first abutting ring and the second abutting ring, wherein the coded body may comprise a supporting element on which the first abutting ring, the second abutting ring and the plurality of locking rings are assembled. 
     A further embodiment of the invention may refer to a safety device designed to cover an element or a hole which needs to be placed in a safe condition, wherein the safety device comprises: a safety cover, a first locking element and a second locking element positioned between the safety cover and the element or hole to be placed in a safe condition, wherein the safety cover comprises a first contact surface and a second contact surface, wherein the first locking element comprises a first abutting element configured in such a way that it abuts the first contact surface, wherein the second locking element comprises a second abutting element configured in such a way that it abuts the second contact surface, and wherein the first contact surface is not coplanar with the second contact  20  surface. 
     In some embodiments, the safety device may comprise: at least one first sealing ring and a second sealing ring, wherein the first sealing ring may comprise an oblique surface, and wherein the second sealing ring may comprise a surface that is at least partially complementary with the shape of the abutting element. 
     In some embodiments, the safety device may comprise: a thrust ring suited to thrust the first sealing ring and the second sealing ring. In some embodiments, the safety device may comprise: at least one first sealing ring and a second sealing ring, at least one first thrust element, wherein the first thrust element is configured to thrust the second sealing ring towards the first sealing ring. 
    
    
     
       BRIEF LIST OF THE DRAWINGS 
       Further characteristics and advantages of the invention will be highlighted through the analysis of the following detailed description of some preferred but not exclusive embodiments, which are illustrated by way of indicative and not limiting example with the support of the attached drawings. In the drawings, the same reference numbers identify the same components. 
       In particular: 
         FIGS. 1A to 1G  schematically show a safety device  1000  according to an embodiment of the invention; 
         FIG. 2  schematically shows a method of use of the safety device  1000 ; 
         FIGS. 3 to 5  schematically show safety devices  3000 ,  4000 ,  5000  according to alternative embodiments of the invention; 
         FIGS. 6, 6A, 7 and 8  schematically show locking elements  6200 ,  7200 ,  8200  and a safety device  6000  according to alternative embodiments of the invention; 
         FIGS. 9A to 9D  schematically show a coded body  9100  according to an alternative embodiment of the invention; 
       Figure schematically shows a method of use of the coded body  9100 ; 
         FIGS. 11, 12, 13, 14A and 14B  schematically show safety devices  11000 ,  12000 ,  13000 ,  14000  according to alternative embodiments of the invention; 
         FIG. 15  schematically shows a safety device  15000  according to an alternative embodiment of the invention and the respective method of use; 
         FIG. 16  schematically shows locking elements according to alternative embodiments of the invention; 
         FIGS. 17A and 17B  schematically show a safety device  17000  according to an alternative embodiment of the invention; 
         FIG. 18  schematically shows a safety device  18000  according to an alternative embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1A to 1G  schematically illustrate an embodiment of the invention.  FIG. 1A  schematically shows an exploded view of the safety device  1000 , while  FIG. 1B  schematically shows the application of a safety device  1000  to an element S which needs to be placed in a safe condition. In the case illustrated in  FIG. 1B , the element S to be placed in a safe condition is a bolt. However, the present invention should not be considered limited to this type of elements to be placed in a safe condition but, for example, it can be used to place in a safe condition any element that must not be rotated, pressed, removed or accessed. 
     As can be seen in  FIG. 1A , the safety device  1000  comprises a coded body  1100 , a safety cover  1400  and one or more locking elements  1200 ,  1300 . In the embodiment illustrated in  FIG. 1A , the number of locking elements is two; however, according to the following description, it is clear that a different number of locking elements can be used. Generically, the locking elements  1200 ,  1300  are configured in such a way as to allow the safety cover  1400  to be removed from the coded body  1100  through a simple movement of the safety cover  1400  according to a predetermined combination. 
     In the embodiment illustrated herein, the safety cover  1400  comprises an inner cover  1410 , an anti-perforation element  1420  and an outer cover  1430 . However, it can be understood that the safety cover  1400  can be made as a single element, as clearly explained in the following description. The inner cover  1410  will be described in greater detail in the remaining part of the description in order to illustrate the characteristics which make it possible to lock and release the safety device  1100 . 
     The anti-perforation element  1420  has the function to prevent the perforation of the safety cover  1400  by staff who is not authorized to remove it. Thus, the anti-perforation element  1420 , for example, may be a special plate made of an anti-perforation metal. It will therefore be clear that the anti-perforation element  1420  is to be considered as an optional, since embodiments will be possible in which resistance to perforation may  20  be considered unnecessary, or embodiments will be possible in which the inner cover  1410  and/or the outer cover  1430  are made of an anti-perforation metal. 
     The outer cover  1430  has a similar function of protecting the inner cover  1410 , in addition to facilitating the production of the device, since it makes it possible to use different materials and/or moulds for the inner cover  1410  and for the outer cover  1430 . However, as in the case of the anti-perforation element  1420 , the outer cover  1430  is to be considered as an optional and it will be possible to provide an embodiment in which the function of the outer cover  1430  is served by the inner cover  1410 . 
     The locking element  1200  and the locking element  1300  are positioned between the coded body  1100  and the safety cover  1400 . Specifically, in the embodiment illustrated herein, they are positioned between the coded body  1100  and the inner cover  1410 . Even more specifically, in the embodiment illustrated herein and as better clarified in the description below, they are previously inserted in the inner cover  1410 , inside respective seats, so that when the safety cover  1400  is placed on the coded body  1100  they come to be positioned between the two elements. 
     For this purpose, in the embodiment illustrated herein, the locking elements  1200 ,  1300  have a substantially circular shape and/or a shape that allows their elastic compression. More specifically, in the embodiment illustrated herein, the locking elements  1200 ,  1300  are snap rings, which means that they behave elastically, as is known. Specifically, they can be compressed, inserted in their respective seats and released, so that the elastic thrusting action they exert on the safety cover  1400  maintains them in position with respect to the safety cover  1400 . Specifically, their insertion in their respective seats prevents them from moving in the longitudinal direction of extension of the cavity of the safety cover  1400 . On the contrary, even though they are pressed against the safety cover  1400 , they can rotate with respect to the latter, as described here below, following the application of sufficient force. As can be seen in  FIG. 1B , the application of the safety device  1000  to the element to be placed in a safe condition S is obtained through a first application of the coded body  1100  to the element to be placed in a safe condition S, followed by the application of the safety cover  1400 , inside which the locking elements  1200  and  1300  were previously positioned, to the coded body  1100 . Specifically, in the embodiment illustrated herein, as can be seen in  FIG. 1C  which shows several views of the coded body  1100 , the coded body  1100  comprises a fixing element  1110  whose shape allows it to be restrained in the element to be placed in safety condition S. In the embodiment illustrated herein, the fixing element  1110  is constituted by a plurality of small blades which are compressed by inserting them in a corresponding hole provided in the element to be placed in a safe condition S, in such a way as to ensure the union between the coded body  1100  and the element to be placed in a safe condition S. It will be clear, however, that different embodiments of the fixing element  1110  are possible. For example, it will be possible to make the fixing element  1110  with a different shape, which however should make it possible to join the coded body  1100  to the element to be placed in a safe condition S in such a way that they are substantially integral with each other. In alternative embodiments, it will also be possible to glue or weld the safety device  1000  onto the element to be placed in a safe condition S, so that the fixing element  1110  consists of glue, a weld or similar systems. In some embodiments, the component  1100  and the component S, instead of being joined to each other, can be replaced by a single piece constituted, for example, by a mould. 
     As shown in  FIG. 1D , the coded body  1100  is provided with a contact surface  1130  and a contact surface  1140 . In the embodiment illustrated herein, the contact surface  1130 , as well as the contact surface  1140 , extends in a substantially radial direction with respect to the longitudinal axis of extension of the coded body  1100 . This embodiment, however, is not necessary. In fact, it will be sufficient for the contact surface  1130  and/or the contact surface  1140  to have such a shape that they can lock the movement of the locking elements  1200 ,  1300 , as is clear from the following description. 
     The locking element  1200  comprises an abutting element  1220  configured in such a way that it abuts the contact surface  1130 . In a similar manner, the locking element  1300  comprises an abutting element  1320  configured in such a way that it abuts the contact surface  1140 . In this specific embodiment, the locking elements  1200 ,  1300  are substantially provided with a body  1210 ,  1310  in the shape of a snap ring, meaning substantially the shape of an arc of a circle, with radial extension preferably included between 210 degrees and 350 degrees. 
     Always in the embodiment illustrated herein, the locking elements  1200 ,  1300  are also provided with an abutting element  1220 ,  1320 , configured in such a way that it abuts a corresponding contact surface. Specifically, in the embodiment illustrated herein, the abutting element  1220 ,  1320  is obtained through an extension of the body  1210 ,  1310  oriented in a substantially radial direction with respect to the body  1210 ,  1310 . More specifically, in the embodiment illustrated herein, the extension of the abutting element  1220 ,  1320  is oriented towards the inside of the body  1210 ,  1310 . However, the present invention is not limited to this embodiment and an extension oriented towards the outside of the body  1210 ,  1310  will also be possible. Furthermore, in the embodiment illustrated herein, the length of the abutting element  1320  exceeds the length of the abutting element  1220 . This embodiment makes it possible to obtain the contact surfaces  1130 ,  1140  in a simpler and more effective manner. However, the invention is not limited to this embodiment and it will be possible to implement it with abutting elements  1220 ,  1320  having the same length. 
     In the embodiment illustrated in  FIG. 1D , the contact surface  1130  is not coplanar with the contact surface  1140 . This characteristic, as clearly explained in the description provided below, allows the safety cover to be extracted from the element to be placed in a safe condition S only by staff who know the coding of the coded body  1100 . 
     As can be seen in  FIG. 1E , which shows a sectional view of the inner cover  1410 , the inner cover  1410  comprises seats  1412 ,  1413  in a number corresponding to the number of locking elements  1200 ,  1300 . The locking elements  1200 ,  1300  are inserted in the respective seats  1412 ,  1413  through the compression of the locking elements  1200 ,  1300 , the respective positioning of the same in the seats and their elastic release. As can also be seen in the figure, the inner cover  1410  is provided with internal grooves  1411 . The grooves  1411  have a shape that matches the external shape of the element to be placed in a safe condition S. Specifically, the shape of the grooves  1411  is such as to allow the rotation of the inner cover  1410  on the element to be placed in a safe condition S with clicks. In other words, the size of the grooves  1411  is such that it allows the movement of the inner cover  1410  with respect to the surface of the element to be placed in a safe condition S, but only through the application of a force that must be sufficient to overcome the interaction between the grooves  1411  and the external shape of the element to be placed in a safe condition S. This interaction is constituted by the clicks mentioned above which, as clearly explained below, allow the staff authorized for the removal of the safety cover  1400  to execute the combination associated with the coded body  1100  in such a way as to remove the safety cover  1400 . It will be clear, however, that the invention can be implemented also without the grooves  1411 , through a simple visual measurement of the rotation angle of the safety cover  1400 . In order to facilitate this operation, the safety cover  1400  and/or the coded body and/or the element to be placed in a safe condition S may comprise one or more alignment marks, not illustrated herein. 
     As can be seen in  FIG. 1D , the coded body  1100  comprises a coding cavity  1160  inside which the abutting element  1220  and the abutting element  1320  can be positioned. In the direction of movement of the abutting elements  1220 ,  1320 , the coding cavity is included between the contact surface  1130  and a contact surface  1131  and between the contact surface  1140  and a contact surface  1141 . In some embodiments, furthermore, the contact surface  1131  may advantageously not be coplanar with the contact surface  1141 . 
     As can be seen in  FIG. 1D , the coded body  1100  comprises a release cavity  1170  connected to the coding cavity  1160 , through which the abutting element  1220  and the abutting element  1320  can pass. Specifically, once having been aligned as described below, the locking elements  1200  and  1300 , or at least the abutting elements  1220 ,  1320 , can pass through the release cavity  1170  in order to release the safety device  1000 . 
       FIG. 1F  shows a sectional view of the inner cover  1410 , also visible in  FIG. 1E , when mounted on the element to be placed in a safe condition S.  FIG. 1G  shows a sectional view of the inner cover  1410 , also visible in  FIG. 1E , together with the remaining part of the inner cover  1410 . As can be observed, the terminal portion of the inner cover  1410  comprises one or more thrust elements  1414 , for example elastic tabs, configured in such a way as to thrust the inner cover in the opposite direction with respect to the coded body  1100 . The thrust elements  1414  are to be considered as optional, as is evident from the following description. In the embodiments including the thrust elements  1414 , these make it possible to move the safety cover  1400  away from the coded body. This advantageously makes it possible to insert a part of at least one of the locking elements  1200 ,  1300 , for example the abutting element  1320 , into apposite grooves  1120 . Consequently, this makes it possible to prevent any accidental movement of the abutting element  1320  with respect to the coded body  1100 . Specifically, as the locking elements  1200 ,  1300  are fitted elastically in the safety cover  1400 , they generate friction with respect to the safety cover  1400 . This means that when the position of the locking elements  1200 ,  1300  is fixed the safety cover  1400  can rotate in any case, if a force exceeding the friction present between these elements is applied. On the contrary, if the position of the locking elements  1200 ,  1300  is not fixed, they rotate together with the safety cover  1400 . 
       FIG. 2  schematically illustrates a method of use of the embodiment of the invention illustrated in  FIGS. 1A to 1G . Specifically,  FIG. 2  schematically illustrates a top section view of the locking elements  1200  and  1300 , as well as a simplified view of the part of the coded body  1100  which interacts with the locking elements  1200  and  1300 .  FIG. 2  illustrates different operating steps S 20 -S 28 . The movement of the safety cover  1400  with respect to the coded body  1100  is schematically illustrated on the left of each step. As can be seen in  FIG. 2 , in step S the safety cover  1400  is moved in the direction of the coded body  1100 , which results in the insertion of the locking elements  1200  and  1300  through the cavity  1170 . In step S 21 , the locking elements  1200  and  1300  are thus inside the cavity  1160 . From this step, a sufficient rotary movement of the safety cover  1400  to the right or to the left locks the safety cover  1400  and prevents its extraction from the coded body  1100 . 
     By way of example, in step S 22  the safety cover  1400  is rotated to the right, that is, clockwise, with respect to the coded body  1100 . Since the locking elements  1200  and  1300  are positioned inside their seats in the safety cover  1400 , in the absence of, other forces acting on them they move together with the safety cover  1400 , and parallel, as illustrated above. 
     At the end of step S 22 ; the abutting element  1320  of the locking element  1300  comes into contact with the contact surface  1140 . A successive rotation of the safety cover  1140  does not lead to the rotation of the locking element  1300 , which is prevented by the interaction of the abutting element  1320  with the contact surface  1140 . On the contrary, since the contact surface  1140  occupies a position inside the cavity  1160  which is not on the plane of movement of the abutting element  1220  of the locking element  1200 , a successive rotation of the safety cover  1400  results in a movement of the locking element  1200  leading to the contact with the contact surface  1130 , as illustrated in step S 23 . 
     At this point, the safety cover cannot be separated from the coded body  1100 . Actually, the abutting elements  1220 ,  1320  would come into contact with the grooves  1120 , or with the coded body, if the cavities  1120  were not present, thus preventing the separation of the safety cover  1400  from the coded body  1100 . The pressure exerted on the safety cover  1400  can thus be interrupted. The thrust elements  1414 , which in this case are provided, make at least the abutting element  1320  enter a groove  1120 , which advantageously prevents any accidental movement of the locking element  1300  with respect to the coded body  1100 , thanks to the frictional assembly of the locking element  1300  in the safety cover  1400 . At this point, a random clockwise or anticlockwise rotation of the safety cover  1400  does not allow the separation of the safety cover  1400  from the coded body  1100 . First of all, this happens because the rotation of the locking element  1300  would be impossible, being prevented by the fact that it is positioned in the groove  1120 . In any case, even if pressure is exerted on the thrust elements  1414 , or if these are not provided, since the two locking elements  1200 ,  1300  are not aligned any more, it is not possible to extract both the abutting elements  1220  and  1320  from the cavity  1170 . 
     In greater detail, as illustrated in steps S and S 26 , an anticlockwise movement makes the locking element  1320  rest against the contact surface  1141 . The uncontrolled continuation of the rotation would cause the locking element  1220  to rest against the contact surface  1131 , thus returning to a locked configuration. On the contrary, as illustrated in step S 27 , a controlled anticlockwise rotation results in the alignment of the locking elements  1220  and  1320 . At this point, as shown in step S 28 , it is possible to move the two locking elements  1220  and  1320  above the cavity  1170  and proceed to release the device  1000 . 
     The alignment of the locking elements  1220 ,  1320  thus depends on the relative position of the contact surfaces  1130 ,  1131 ,  1140  and  1141 , so that only those who know their position and the rotary movement or the combination required to align the locking elements  1220 ,  1320  can release the device  1000 . 
     It will be clear that, in the situation described above, in the presence of the thrust elements  1414 , the rotation steps are possible only if a thrusting action allows the locking elements  1220 ,  1320  to be released from the grooves  1120 . The use of the combination, in the presence of the thrust elements  1414 , thus requires the correct application of thrusting and rotation movements together. Furthermore, it will be clear that alternative embodiments can be implemented, in which the device can be configured in such a way that instead of thrusting the safety cover  1400  to release the locking elements  1220 ,  1320  so as to allow them to rotate together with the safety cover  1400 , it will be necessary to pull the safety cover  1400 . 
     In some embodiments, the distance between the contact surface  1130 ,  1131  and the release cavity  1170  and/or the distance between the surface  1140 ,  1341  and the release cavity  1170  depends on the position of the grooves  1411 , and is preferably equal to the angular dimension of a plurality of grooves  1411 , even more preferably equal to a multiple of the angular dimension of one of the grooves  1411 . In some embodiments, the angular dimension of the grooves  1120  corresponds to the angular dimension of the abutting elements  1220 ,  1320 . Consequently, the size of the cavity  1160  depends on the size of the grooves  1120  and the cavity  1170 . The grooves  1411  are positioned in such a way as to produce a noise, or a click, which takes place through the interference between the grooves  1411  and the external shape of the element S during rotation. The angular dimension of the grooves  1411  can thus be calculated in such a way as to obtain that the noise or click corresponds to the distance covered by the locking element  1200 ,  1300  between a groove  1120  and the successive one. This solution is particularly advantageous, since the combination, instead of being expressed in rotation angles, can be expressed as the number of clicks produced by the grooves  1411  on the element S or the coded body  1100 . Since the distances that define the combination are equal to a multiple of the angular dimension of the grooves, the combination will thus be easy to memorize as a number of clicks in one or more directions rather than as a rotation by a certain angle. 
       FIGS. 3 to 6  schematically illustrate alternative embodiments of the invention. 
     Specifically,  FIG. 3  illustrates an embodiment with three locking elements instead of the two locking elements described above. Also in this case, the lack of coplanarity between at least two of the contact surfaces results in the misaligned positioning of the respective locking elements, so that one or more rotations according to a predetermined combination are required to align the locking elements again and proceed to release the device. 
       FIG. 4  schematically illustrates an embodiment in which, contrary to the explanation provided above, the position of the contact surfaces is not symmetrical with respect to the cavity  1170 . The invention can work also in this case. 
       FIG. 5  schematically illustrates an embodiment in which there are no grooves  1120 . The invention can work also in this case, since the misaligned configuration that stops the locking elements does not depend on the presence of the grooves  1120 . 
       FIG. 6  schematically illustrate a locking element  6200 , which is a possible variant of the locking element  1200  and/or of the locking element  1300  described above. Specifically, the locking element  6200  comprises an abutting element  6220  that is not positioned at one end of the body  6210 , as described above with reference to the locking element  1200 , but rather in a part of the body  6210  which is included between its two ends, preferably in a substantially median position with respect to the two ends. It will be clear that the invention can work in a similar manner if one or more of the locking elements  1200 ,  1300  is/are replaced with a locking element  6200 . 
       FIG. 7  schematically illustrates a locking element  7200 , which is a possible variant of the locking element  1200  and/or of the locking element  1300  and/or of the locking element  6200  described above. Specifically, the locking element  7200  comprises an abutting element  7220  positioned in a part of the body  7210  which is included between the two ends of the body  7210 . In this case, the body  7210  has the shape of an arc of a circle with an angle preferably smaller than 180°, more preferably smaller than 90°. Since in this case an elastic insertion as in the cases described above is not possible, in order to prevent the locking element  7200  from moving with respect to the safety plug  7400  two sealing rings  7230 ,  7231  are used, between which the locking element  7200  is kept pressed. The pressure is obtained by means of a thrust ring  7250 , whose shape is such as to exert an elastic thrusting action in the longitudinal direction of extension of the safety cover  7400 , and of a locking ring  7240 , for example a snap ring. It will thus be clear that the safety cover  7400  comprises at least one seat for the locking ring  7240 , even if not shown. It will be clear that the invention can work in a similar manner if one or more of the locking elements  1200 ,  1300 ,  6200  is/are replaced with a locking element  7200 . 
     In some embodiments, visible for example in  FIG. 6 , the locking element  6200  comprises a body  6210  which describes a plane. In other words, there is a plane that includes the body  6210 . The abutting element  6220  can also belong to the plane or it can be inclined with respect to said plane, preferably with an angle included between 5° and 20°. The inclination of the abutting element  6220  allows the safety cover  1400  to behave elastically while being fitted on the coded body  1100  and to thrust against the grooves  1120 , or in any case against the corresponding surface if they are not provided, in response to an attempt to separate the safety cover  1400  from the coded body  1100 . This characteristic advantageously makes it possible to fit the safety cover  1400  on the coded body  1100  independently of the alignment between the abutting element  6220  and the release cavity  1170 . On the contrary, what has been described above applies for the release operation. 
     According to a further embodiment, visible in  FIG. 6A , the locking element  6200  is used in a safety device  6000  comprising the locking element  6200 , so that it is possible to lock a safety cover  6400  on the element S. The safety cover  6400  is thrust in the opposite direction with respect to the element S by a thrust element  6414 , for example a spring or magnets. Thanks to the advantageous shape of the locking element  6200 , the abutting element  6220  does not necessarily need to be inserted through the locking cavity  6170 . On the contrary, as can be seen in  FIG. 6A , it is possible to insert the abutting element  6220  in any position, thanks to its elastic behaviour. However, as in the previous examples and thanks to the shape of the locking element  6200 , its extraction will be possible only through the locking cavity  6170 . The thrusting action of the thrust element  6414  guarantees that the extraction is not possible in any other way. 
       FIG. 8  schematically illustrates a locking element  8200 ,  8300 , which is a possible variant of the locking element  1200  and/or of the locking element  1300  and/or of the locking element  6200  and/or of the locking element  7200  described above. Specifically, the locking element  8200 ,  8300  comprises an abutting element  8220 ,  8320  in a substantially spherical shape. Since also in this case an elastic insertion as in the cases described above is not possible, in order to prevent the abutting element  8220 ,  8320  from moving with respect to the safety plug  8400  two sealing rings  8230 ,  8231  are used, between which the abutting element  8220  is kept pressed. The combination of the sealing rings  8230 ,  8231  and the abutting element  8220  thus produces the locking element  8200 . Analogously, the abutting element  8320  is kept pressed between the sealing ring  8231  and the thrust ring  7250 , which works as described above. It will be clear that the invention can work in a similar manner if one or more of the locking elements  1200 ,  1300 ,  6200 ,  7200  is/are replaced with a locking element  8200 ,  8300 . 
     In the embodiment illustrated above, the safety cover  8400  comprises grooves  8411  whose function is similar to that of the grooves  1411  described above. It is clear that also in this case the invention can be carried out without the grooves  8411 . 
     In the embodiment illustrated above, the safety cover  8400  comprises one or more anti rotation teeth  841  corresponding to one or more anti rotation notches  8232  respectively provided in the sealing ring  8230 ,  8231 . These characteristics, which should be considered optional, prevent the rotation of the sealing ring  8230 ,  8231  with respect to the safety cover  8400 . 
       FIGS. 9A to 9D  schematically show a coded body  9100  according to an alternative embodiment of the invention. Specifically, the coded body  9100  differs from the coded body  1100  as it allows the combination, or the coding of the coded body, to be programmed. 
     More specifically, the coded body  9100  comprises at least one abutting ring  9133  and one abutting ring  9142 , wherein the abutting ring  9133  comprises a contact surface  9130  and wherein the abutting ring  9142  comprises a contact surface  9140 . The function of the two contact surfaces  9130  and  9140  is similar to that of the contact surfaces  1130  and  1140  described above. In addition to the above, the coded body  9100 , as illustrated, comprises an abutting ring  9132  and an abutting ring  9143 , wherein the Abutting ring  9132  comprises a contact surface  9131 , and wherein the abutting ring  9144  comprises a contact surface  9141 , whose function is similar to that of the contact surfaces  1131  and  1141 . It will be clear that, although in the embodiment illustrated above there are four abutting rings, each one with a single contact surface, it will be possible to implement two contact surfaces in a single abutting ring, thus reducing the possibility to configure the coded body, but in any way maintaining a possibility of configuration. Two different configurations of the contact surfaces are illustrated, for example, in the two examples of  FIG. 9D . 
     In order to allow the modification of the combination of the coded body  9100 , the abutting rings can be moved with respect to each other in a coding position of the coded body  9100  and are fixed with respect to each other in a locking position of the coded body  9100 . The passage between the locking position and the coding position can be obtained in different manners, for example by exerting pressure on the rings so that they are locked due to the friction that is generated or inserting locking elements in suitable slots provided in the abutting rings, not illustrated herein, in such a way as to prevent their mutual movement. In the embodiment illustrated, the coded body  9100  comprises a plurality of locking rings  9191 ,  9192 ,  9193  between which the abutting rings are positioned. The number of locking rings illustrated is three; however it is clear that the invention can also be carried out only with the locking rings  9191  and  9193 . In the embodiment illustrated, the locking rings produce friction and thus lock the abutting rings  9132 ,  9133 ,  9142 ,  9143  and are fitted on a supporting element  9194 . The supporting element  9194  can be threaded, in order to allow one or more of the locking rings  9191 - 9193 , preferably the locking ring  9191 , to be screwed therein, in such a way as to exert pressure on the abutting rings and thus pass from the coding position, when loosening, to the locking position, when tightening. 
     In the embodiment illustrated, the supporting element  9194  has a hollow cylindrical shape, in such a way as to allow access to the hole to be placed in a safe condition S. It will be clear; however, that alternatively any shape allowing the assembly of the abutting rings and the locking rings can be implemented. 
     In the embodiment illustrated, the locking rings have complementary surfaces, so that in the locking position the complementary surfaces of two adjacent locking rings mesh with each other in order to prevent the mutual rotation of the locking rings. In the embodiment illustrated, the complementary surfaces are obtained through a half-cylinder which extends from the surface of each one of the locking rings in the longitudinal direction of extension of the supporting element  9194 . This configuration advantageously makes it possible to avoid the rotation between the locking rings and, since the two complementary half-cylinders form a complete cylinder, provides also a cylinder on which the abutting rings  9132 ,  9133 ,  9142 ,  9143  can be assembled. 
     In some embodiments not illustrated herein, it will be possible to create an external surface of the half-cylinders which at least partially comprises locking teeth intended to interact with locking cavities provided in the abutting rings  9132 ,  9133 ,  9142 ,  9143 . In this way, it will be possible to lock the abutting rings in a specific position, thanks to the fixing obtained between the locking teeth and the locking cavities during the assembly of the coded body  9100 . 
       FIG. 10  schematically shows a method of use of the coded body  9100 . The method is substantially similar to that already described with reference to  FIG. 2 . In this case, the embodiment illustrated comprises two locking rings  9192 ,  9193  with two release cavities  9171 ,  9172 . It will be clear, however, that in alternative embodiments it will be possible to obtain a similar function by using a single locking ring  9193  and a single release cavity  9172 . In the embodiments illustrated in  FIGS. 9A-9D and 10 , the locking rings  9192 ,  9193  comprise grooves  9120  whose function is similar to that of the grooves  1120  described above. Therefore, the observations on the function and the optional presence of the grooves  1120  apply also to the grooves  9120 . 
       FIGS. 11, 12, 13   14 A and  14 B schematically show safety devices  11000 ,  12000 ,  13000 ,  14000  according to alternative embodiments of the invention. 
     Specifically, each one of the safety devices  11000 - 13000  comprises abutting elements  8220 ,  8320  similar to those previously described with reference to  FIG. 8 . Differently from  FIGS. 9A-9D and 10 , none of the devices  11000 - 13000  is provided with the grooves  9120  in the cavity of the coded body. It is possible, however, to prevent any accidental movement of the safety plug with respect to the coded body by applying pressure between the abutting elements  8220 ,  8320  and the coded body. In the case of  FIG. 11 , pressure is exerted by a thrust element  11414 , for example a spring, positioned between the inner cover  11410  and the outer cover  11430 . In the case illustrated in  FIG. 12 , the thrust element  12414  is constituted by two magnets positioned between the inner cover  12410  and the outer cover  12430  in such a way as to mutually repel each other and thus move the inner cover  11410  away from the outer cover  11430 . In the case of  FIG. 13 , the thrust elements  1414  described above are used. It will be clear that the thrust elements  11414 ,  12414  can be used also in embodiments comprising locking elements different from the locking elements  8200 ,  8300 . 
     In the embodiment illustrated in  FIG. 13 , it is also possible to observe grooves  13411  located on the external surface  1180  of the coded body. The function of the grooves  13411  is similar to that of the grooves  1411 ,  8411  described above, and they serve as elements suited to produce the clicks described above when the safety cover is rotated. 
     The embodiment illustrated in  FIG. 14  differs from all the previous embodiments in that the locking elements  14200 ,  14300  are assembled on the element to be placed in a safe condition S, instead of on the safety cover, and the coded body is executed in the safety cover  14400 . In the embodiment illustrated, the locking elements  14200  and  14300  are similar to the locking elements  1200 ,  1300 , the only difference lying in that the abutting elements  14220 ,  14320  are oriented in the direction of the safety cover  14400 . In other words, the shape of the locking elements  14200  and  14300  allows them to behave elastically, so that they can be fitted on the element S through friction. In this case, the elastic force acts through compression rather than through expansion, as in the case of the locking elements  1200 ,  1300 . Consequently, the abutting elements, instead of being oriented towards the inside of the locking elements, as in the case of the locking elements  1200 ,  1300 , are oriented towards the outside of the same. The safety device  14000  can thus be used to cover an element or hole S to be placed in a safe condition, and comprises a safety cover  14400 , and a locking element  14200  and a locking element  14300  positioned between the safety cover  14400  and the element or hole S to be placed in a safe condition. It is clear that instead of one or more of the locking elements  14200 ,  14300  illustrated above it will be possible to use any of the locking elements  1200 ,  6200 ,  7200 ,  8200  with suitable modifications which will be evident to the experts in the art. 
     The safety cover  14400  comprises a contact surface which, for example, is similar to the contact surface  1130 ,  9130  and a contact surface which, for example, is similar to the contact surface  1140 ,  9140 . The locking element  14200  comprises an abutting element  14220  configured in such a way that it abuts a first contact surface and the locking element  14300  comprises an abutting element  14320  configured in such a way that it abuts a second contact surface, in a manner similar to that described above. As in the previous cases, the fact that the first contact surface is not coplanar with the second contact surface makes it possible to lock the safety cover as described, for example, in relation to  FIGS. 2 and 10 . 
       FIG. 15  schematically shows a safety device  15000  according to an alternative embodiment of the invention and the respective method of use. Specifically, the safety device  15000  presents two differences with respect to the safety devices previously described, which can also be carried out independently and even in combination with each one of the safety devices previously described. More specifically, in the safety device  15000  the sectional size of the abutting elements  15220  and  15320  is different, and furthermore the release cavities are more than one. As is clear from the previous description and as can be seen in  FIG. 15 , in order to release the safety element  15000  it is thus necessary to align the correct abutting element with the correct release cavity, for example the larger abutting element  15320  with the respective release cavity  15171 . 
       FIG. 16  schematically shows locking elements according to alternative embodiments of the invention. Specifically, as is evident from the examples illustrated in  FIG. 16  and from the preceding description, it is sufficient for the shape of the locking element, and more specifically of the abutting element, to project towards the coding cavity, or towards the respective contact surface. Therefore, any of the locking elements shown in  FIG. 16  can be used instead of any of the locking elements previously described. 
       FIGS. 17A and 17B  schematically show a safety device  17000  according to an alternative embodiment of the invention. 
     In this embodiment, the locking elements are fitted on the element to be placed in a safe condition S and the abutting elements  17220 ,  17320  are obtained by means of spheres maintained in position by sealing rings  17230 ,  17231 ,  17233 ,  17234 . As already described, instead of the spheres it will be possible to use other abutting elements, for example one of those shown in  FIG. 16 . 
     As far as the release operation is concerned, this embodiment works in a manner similar to that discussed in relation to  FIGS. 14A and 14B , in which also the locking elements are positioned on the element to be placed in a safe condition S. Also in this case, therefore, the release will take place through the alignment of the abutting elements  17220 ,  17320  in the respective cavity provided inside the safety cover  17400 . 
     Differently from  FIGS. 14A and 14B , however, this embodiment uses abutting elements  17220 ,  17320  similar to those used in the embodiments shown in  FIG. 8 , also for the purpose of clarifying how the different embodiments can be combined with each other. 
     Furthermore, this embodiment adds a characteristic that allows the abutting elements  17220 ,  17320  of this type to behave similarly to the abutting element  6220 . In other words, this embodiment makes it possible to fit the safety cover  17400  on the element to be placed in a safe condition S also in the presence of abutting elements  17220 ,  17320  not necessarily aligned with the release cavity  17170 . 
     This is possible because at least some of the locking rings are movable along the element to be placed in a safe condition S and kept pressed by the thrust ring  17250 , for example a spring. Specifically, as can be seen more easily in FIG.  17 B, when the abutting element  17320  comes into contact with the safety cover  17400 , it is pushed towards the element to be placed in a safe condition S. The movement is possible because the sealing ring  17233  can be moved to the left, thus leaving more space between the sealing rings  17233  and  17234 , in which the abutting element  17320  can be inserted. 
     When the abutting element  17320  enters the coding cavity  17460 , the thrusting force exerted by the thrust ring  17250  moves the abutting element  17320  back to its most external position, in such a way that the latter fits into the coding cavity. The same mechanism can be applied to the insertion of the abutting element  17320  in the coding cavity  17461  and to the insertion of the abutting element  17220  in the coding cavity  17460 . It is therefore possible, as in the case of the abutting element  6220 , to insert the abutting element in the respective coding cavity with no need to pass through the release cavity  17170 . 
     Furthermore, it is advantageously possible to prevent the extraction if the abutting elements  17220 ,  17320  are not aligned with the release cavity  17170 . 
     This is advantageously obtained by making the sealing rings  17230  and  17231 , as well as the sealing rings  17233  and  17234 , in an asymmetrical manner. 
     Specifically, as can be more easily seen in  FIG. 17B , the sealing ring  17230  comprises an oblique surface  17235 , while the sealing ring  17231  comprises a surface  17236  which is at least partially complementary to the shape of the abutting element  17220 . 
     During the insertion, the abutting element  17220  is pushed outside of the complementary surface  17236  and along the oblique surface  17235 . Thanks to the angular position of the oblique surface  17235 , this results in a thrusting action of the sealing, ring  17230  to the left, thus opening a space between the sealing rings  17230  and  17231 , as previously described. During the extraction of the safety cover  17400 , the abutting element  17220  is pushed against the complementary surface  17236 . Thanks to the fact that the external shape of the abutting element  17220  matches that of the complementary surface  17236 , the abutting element  17220  remains confined by the complementary surface  17236  and cannot move, thus preventing the extraction of the safety cover  17400 . It will be clear that this behaviour can be applied in a similar manner to the abutting element  17320 . In some embodiments, furthermore, anti-rotation notches  17215  can be 5 provided, which cooperate with anti-rotation teeth  17232  in order to avoid the rotation of the sealing rings. Furthermore, the length of the different anti rotation notches  17215  along the element to be placed in a safe condition S can be different, in such a way as to define the maximum position that can be reached by the sealing rings along the element to be placed in a safe condition S. 
       FIG. 18  schematically shows a safety device  18000  according to an alternative embodiment of the invention. 
     In this case, the thrust elements  18250 ,  18251  are positioned between the sealing rings  18230 ,  18231 ,  18233 ,  18234 . 
     At least the sealing rings  18230 ,  18232  are provided with grooves that allow the partial insertion of the abutting elements  18220 ,  18320 . Thanks to the possibility of movement offered by the thrust elements  18250 ,  18251 , for example springs or magnets, the sealing rings  18231  and  18233  can move along the element to be placed in a safe condition. In this way, it is possible to release the abutting elements  18220 ,  18320 , which otherwise are held in a fixed position between the respective sealing rings. 
     Thus, more specifically, pulling the element to be placed in a safe condition S, or the safety cover  18400 , makes the abutting elements  18220 ,  18320  rest against a surface which limits the coding cavity  18460 ,  18461 , especially along the surface which is substantially parallel to the sealing rings  18230 , 18231 ,  18233 ,  18234  and positioned, for the respective coding cavity  18460 ,  18461 , towards the direction of extraction of the abutting elements  18220 ,  18320 . In this manner, by pulling the safety cover  18400  it is possible to release the abutting elements  18220 ,  18320  from the respective sealing rings  18230 ,  18231 ,  18233 ,  18234 , thus allowing the abutting elements  18220 ,  18320  to move with respect to the element to be placed in a safe condition S. 
     In this embodiment it will consequently be possible to implement a combination according to which the safety cover  18400  is pulled and rotated so as to extract it from the element to be placed in a safe condition S. 
     Even though, for the sake of clarity, in the description provided above the different embodiments have been described independently, each with a specific set of characteristics, it is clear that subsets of characteristics of any embodiment can be implemented, in such a way as to obtain a new embodiment. It will also be clear that any number of characteristics of an embodiment can be implemented together with any number of characteristics of one or more other embodiments, in such a way as to obtain a new embodiment. Thus, the possible embodiments of the invention are not limited to those described above but include any embodiment falling within the scope defined by the following claims. 
     LIST OF THE REFERENCE NUMERALS 
     
         
           1000 : safety device 
           1100 : coded body 
           1110 : fixing element 
           1120 : grooves 
           1130 ,  1131 ,  1140 ,  1141 : contact surface 
           1150 : external surface 
           1160 : coding cavity 
           1170 : release cavity 
           1180 : external surface 
           1200 ,  1300 : locking element 
           1210 ,  1310 : body 
           1220 ,  1320 : abutting element 
           1400 : safety cover 
           1410 : inner cover 
           1411 : grooves 
           1412 ,  1413 : seat 
           1414 : thrust element 
           1420 : anti perforation element 
           1430 : outer cover 
         S: element to be placed in a safe condition 
         S 20 -S 28 : method of use 
           3000 : safety device 
           4000 : safety device  5000 : safety device 
           6000 : safety device 
           6160 : coding cavity 
           6170 : release cavity 
           6200 : locking element 
           6210 : body 
           6220 : abutting element 
           6400 : safety cover 
           6414 : thrust element 
           7200 : locking element 
           7210 : body 
           7220 : abutting element 
           7230 ,  7231 : sealing ring 
           7240 : locking ring 
           7250 : thrust ring 
           7400 : safety cover 
           8200 ,  8300 : locking element 
           8220 ,  8320 : abutting element 
           8230 ,  8231 : sealing ring 
           8232 : anti rotation notches 
           8400 : safety cover 
           8411 : grooves  8415 : anti rotation teeth 
           9100 : coded body 
           9120 : grooves 
           9130 ,  9131 ,  9140 ,  9141 : contact surface 
           9132 ,  9133 ,  9142 ,  9143 : abutting ring 
           9171 ,  9172 : release cavity 
           9191 ,  9192 ,  9193 : locking ring 
           9194 : supporting element 
           11000 : safety device 
           11410 : inner cover 
           11430 : outer cover 
           11414 : thrust element 
           12000 : safety device 
           12410 : inner cover 
           12430 : outer cover 
           12414 : thrust element 
           13000 : safety device 
           13411 : grooves 
           14000 : safety device 
           14170 : release cavity 
           14200 ,  14300 : locking element 
           14220 ,  14320 : abutting element 
           14400 : safety cover 
           15000 : safety device 
           15170 ,  15171 : release cavity 
           15220 ,  15320 : abutting element 
           17000 : safety device 
           17170 : release cavity 
           17215 : anti rotation notches 
           17220 ,  17320 : abutting element 
           17230 ,  17231 ,  17233 ,  17234 : sealing ring 
           17232 : anti rotation teeth 
           17235 : oblique surface 
           17236 : complementary surface 
           17240 : locking ring 
           17250 : thrusting ring 
           17400 : safety cover 
           17460 ,  17461 : coding cavity 
           18000 : safety device 
           18220 ,  18320 : abutting element 
           18230 ,  18231 ,  18233 ,  18234 : sealing ring 
           18240 : locking ring 
           18250 ,  18251 : thrust element 
           18400 : safety cover 
           18460 ,  18461 : coding cavity