Abstract:
A cushioning device for opening and closing of sliding shutters, particularly of sliding shutters for furniture, to be applied as a single item to each shutter or sliding partition, in order to be able to cushion an end part of their opening and closing movement. The cushioning device includes a cushioning box applied with brackets for support and sliding of the individual shutter; this box being equipped with two opposing braking devices of a rotary type, whose toothed hub directly meshes with a rack fixed to the box, each braking device being joined to its own slider guided by the box and being joined at one end by an elastic device with its opposite end joined to the other slider, both sliders being equipped with a hook for activating and deactivating the corresponding action of the final section of travel to be cushioned.

Description:
BACKGROUND 
       [0001]    This innovation concerns the design of a device to be applied to one of support brackets of any sliding door or shutter, particularly furniture or sliding partitions, in order to cushion their movement, near a point of arrival at ends of gaps or openings that these shutters open or close. 
         [0002]    The use of sliding doors or glass partitions, for example for furniture, display windows, fitted wardrobes or sliding partition walls, is particularly advantageous, compared to hinged systems, due to the fact that it allows for much larger closing and opening surfaces to be designed, without having to provide large spaces in front to allow for opening and closing. 
         [0003]    According to a well-known technique, precisely due to their considerable size, any sliding door or glass partition is usually supported by a pair of brackets or carriages fixed at its upper edges. Each carriage has a corresponding sliding wheel, whose race is joined to a track. The track is mounted on the upper surface of the item of furniture or the void to be closed, whilst a striker or a lower guide, essentially parallel to the upper track, typically forces the side opposite the shutter itself to always remain in a vertical position, even when sliding, using countless structural solutions proposed and illustrated, for example, by EP 0 001 956 dated 1978 or by U.S. Pat. No. 5,247,763 dated 1990 or by EP 0 567 262 dated 1992. 
         [0004]    This same well-known technique in fact, usually requires a pair of voids placed side by side to be closed by a pair of shutters; these, sliding on corresponding parallel tracks and guides placed side by side, allow one of the two voids to be fully opened, overlapping the opened shutter onto the shutter of the closed void, whilst, when both shutters are closing the corresponding voids, they are in any case mounted on two parallel levels, with the edge of one of their central sides ideally aligned or, more often, slightly overlapping the edge of the other shutter. 
         [0005]    All these well-known solutions typically provide for that the void can be closed and opened by pushing or drawing the shutter along its track, with a physical force proportional to the size and therefore the weight of the shutter itself. 
         [0006]    In order to prevent an excessive force pushing the shutter hard against the opening or closing doorstop, the same well-known technique envisages the application of “stoppers” or catches with narrow seat or section, within which a latch can be slotted for the travelling shutter that, due to friction, can slow down its drive, before reaching its doorstop. 
         [0007]    This method, however, has been shown to be rather ineffective, both due to wear over time and, especially, when the shutter is pushed or drawn with excessive force, given that the narrow section of the catch does not manage to retain the shutter latch, which rides over said “stopper”, bouncing against the doorstop and, tending to travel back, partly obstructing the void to be opened, with subsequent manual adjustments to the position of the shutter itself, as well as frequent damage due to vibration from parts being struck. 
         [0008]    A more recent technique aims to overcome this disadvantage, cushioning the end part of the shutter travel, when it is near full opening or closing, exploiting the absorption capacity of an elastic compression device, which is put into contact with the edge of the travelling shutter, in order to then use its reaction force to be discharged gradually into the chamber of a special piston connected to it, for example a pneumatic one, as proposed by Patents EP 1 348 828 and EP 1 426 535 for each of the two sides of the shutter itself. 
         [0009]    Nevertheless, each known cushioning solution, among those mentioned above, has highlighted problems and disadvantages that limit their effectiveness and reduce their use to a few simple cases of furniture or sliding partitions that are not subject to heavy use. 
         [0010]    A first disadvantage is the fact that, as is well-known, pistons have a life limited by the fastness to hold their seal, therefore requiring a foreseeable scheduled maintenance programme that does not seem to be justified, for example for furniture doors. 
         [0011]    A second disadvantage of linking elastic devices and pistons is that, with uncalibrated collisions and thrusting, the piston tends to deform and in any case deteriorate even more often than expected, impacting further on the limited life of the item of furniture or shutter to be closed and opened. 
         [0012]    Another disadvantage of this recent technique is the fact that, as it is well-known, a normal traction spring does not absorb and transmit a thrust uniformly, but proportionally to its expansion or extension, with a consequent increase in the force required to push the shutter at different gap opening or closing positions. 
         [0013]    Finally, all the well-known forms of cushioning with springs and pistons, as above, at most allow the application of only two shutters, given that the devices are applied directly onto the track, thus preventing the translation of the cushioning devices of a possible third sliding shutter. 
       SUMMARY 
       [0014]    The main task of this innovation is in fact being able to construct a single device for the final cushioning of the travel when opening and closing the sliding shutters, on items of furniture for example, without having to apply one per bracket or in any case one for the opening side and one for the closing side of the same shutter. 
         [0015]    In this task, another aim of the innovation is always being able to balance the action of the braking device with the reaction of an adequate elastic device, in order to regulate the final travel of the shutter, independently of its mass and of the variability of the force of the thrust or traction required, as well as of the maximum extension of the elastic device, albeit without having to resort to cumbersome block systems to limit the travel. 
         [0016]    Another aim of this innovation is to be able to construct a cushioning device that is adjustable, adaptable and interchangeable for each type of sliding shutter. 
         [0017]    Another aim of this innovation is to ensure, over time, the efficiency and constancy of operation of the device for the automatic attenuation of the thrust or drawing force, avoiding the damage currently caused each time a shutter collides with its doorstop. 
         [0018]    Another important aim of this innovation is that it does not require scheduled or frequent maintenance, due to wearing of the seals of the current pistons, as well as their fragility against blows or collisions due to undue thrusting. 
         [0019]    A further aim of this innovation is to be able to place this cushioning device onto items of furniture or voids with three or more shutters, without creating obstructions that inhibit the corresponding proper opening and closing operation. 
         [0020]    These and other aims are achieved with a cushioning device according to features of claim  1 . 
         [0021]    A cushioning device for opening and closing of sliding shutters, particularly of sliding shutters for furniture, to be applied as a single item to each shutter or sliding partition, in order to be able to cushion an end part of their opening and closing movement, is characterised by the fact that it is essentially made up of a cushioning box, to be applied with its own brackets or even on brackets for the support and sliding of the individual shutter; this box being equipped with two opposing braking devices, of a well-known viscous fluid rotary type, whose toothed hub directly meshes with a rack fixed to the box itself; each braking device being joined to its own slider guided by the box itself and being joined at one end by an elastic device with its opposite end joined to the other slider, both sliders being equipped with a hook for activating and deactivating the corresponding action of the final section of travel to be cushioned. 
         [0022]    Especially, such a device is characterised by the fact that a cushioning box is made up of a structured box base, with a longitudinal lower slit, on the lower side and with one of its flanks closed by an edge or guiding wall of a cover, said lower slit being capable of connecting the internal cushioning part of the box with the external activation part, for hooking and unhooking, vis-á-vis some strikers mounted near tracks for translation of one or more of the shutters. The structured box or base may have a longitudinal void capable of containing and guiding the longitudinal translation of a pair of sliders in cooperation with the cover that delimits said longitudinal void of the base. Each slider can have the braking device of a viscous fluid rotary type, whose toothed pinions directly mesh with teeth of a rack joined longitudinally to the box. In such device the rack may be integral to the cover. 
         [0023]    In such device the sliders can be joined together by the elastic device working by traction, used to bring the same sliders closer together, overcoming the braking force of their devices. The elastic device is made up of a double helical traction spring, made out of a particularly elastic material, one of the springs being equipped with head hooks or eyelets and the other spring being a internal and coaxial spring and being equipped with head hooks or eyelets that can hook onto the two sliders. 
         [0024]    The lower slit of the box structure can have a pair of lateral slots and/or housings mounted near its two ends. 
         [0025]    The cover may have a small side wall or edge being a little shorter than the length of the lower slit of the box base. 
         [0026]    Especially, the sliders are linked to their corresponding hooks, which are external to the box and can activate a traction action of the elastic device as well as the braking action of the braking devices, due to the contact of these hooks with strikers mounted in a suitable position, near tracks for the sliding and translation of the shutters. 
         [0027]    Following the external or manual opening or closing of such a shutter, the hooks can be housed in their corresponding slots or housings of the lower slit, remaining engaged there until a new contact with the same strikers, acting on their contact housings makes them rotate on the hinge, releasing them from their slot or housing, together with their corresponding sliders, causing the desired cushioning, with the traction reaction of the elastic device and the braking element of the braking devices. 
         [0028]    Following the external or manual opening or closing of a shutter, crooks of the hooks can hook onto the ends of a/the small side wall of the cover, and can remain engaged there until a new contact with the same strikers, acting on their contact housings makes them rotate on their hinge, releasing said crooks at the ends of the small side wall, together with their corresponding slider, causing the desired cushioning, with the traction reaction of the elastic device and the braking element of the corresponding devices. 
         [0029]    A safety hook may be joined to the hook, just as a safety hook is joined to other hook, which safety hooks are equipped with a hooked wall adjoining an inclined wall that can hook the strikers in an initial stage of the application of the device or in subsequent ones when it is newly applied to the sliding shutters. 
         [0030]    The cushioning box can be applied in any position of the upper side of shutter, as well as inverted, compared to the solution mentioned, consequently adjusting the position of the strikers. 
         [0031]    These and other aims are in effect fully achieved with especially a device, which prescribes the design of a single box for cushioning the final movement of the shutter, where the box is used for both the opening and closing phases, and where the box could be applied for example to one of the support and longitudinal sliding brackets of the shutter itself; this box having two opposing braking devices, especially of the well-known viscous fluid rotary type, whose corresponding toothed hub directly meshes with a toothing (or teeth) of a longitudinal rack integral to this box; each braking device being joined to its own slider, which is longitudinally guided by the box itself and is joined to its corresponding elastic device working by traction and with the opposite end joined to the other slider; finally this slider having a hook that activates and deactivates a corresponding cushioning section, due to its contact with corresponding strikers; these strikers being fixed to the roof of a void, near the guide rail and are mounted near shutter&#39;s full opening and closing points on the opening to be closed. 
         [0032]    Especially, the main feature of this innovation is the design of a single box for cushioning a final movement of the shutter, so that it can be used when both opening and closing the same shutter; this box could be applied for example to one of the support and longitudinal sliding brackets of this shutter, or to two independent fixing brackets on the upper side of the shutter. This box has two opposing braking devices, of well-known viscous fluid rotary type, whose corresponding toothed hub directly meshes with a toothing of a single longitudinal rack integral to the box itself; each braking device is joined to its own slider which is guided longitudinally by the box itself and is joined to its corresponding elastic device with the opposite end joined to the other slider; each slider also has a hook for activating and deactivating the corresponding cushioning section, due to its contact with fixed pins arranged near the shutter&#39;s full opening and closing points on the gap being closed. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0033]    A better understanding of the solution proposed and an underlining of the achievement of the aims indicated are described in more detail below and also illustrated, according to a purely indicative and non-restrictive structural form, with the aid of drawings, of which: 
           [0034]      FIG. 1  shows a vertical and cross-sectional view of the upper surface of an item of furniture, on which a section bar is applied with a pair of tracks and the relevant attachments to support the sliding wheels and support brackets for two or more sliding shutters, to which the device in question, for the closing and opening of as many cavities of said item of furniture, should be applied; 
           [0035]      FIG. 2  shows a vertical and cross-sectional view of an upper part of a sliding shutter for the item of furniture in  FIG. 1 , complete with a support bracket for the sliding wheel and the improved device in question, for cushioning the final opening and closing movement of the shutter itself; 
           [0036]      FIG. 3  shows a vertical and cross-sectional view of the upper surface of an item of furniture and the upper part of one of its sliding shutters, as per  FIGS. 1 and 2 , given that the bracket, sliding wheel and shutter cushioning device are already applied to one of the tracks of the upper surface of the item of furniture; 
           [0037]      FIG. 4  shows a perspective view, from above the upper surface of an item of furniture, of a part of the upper surface and one of the upper parts of a shutter and the relevant brackets with sliding and support wheels, plus the application of the cushioning device of the shutter itself to one of said brackets, according to the assembly shown in  FIG. 3 ; 
           [0038]      FIG. 5  shows a perspective and exploded view of the container box, with the cover and the other parts making up the cushioning device in question, already shown in  FIG. 4 ; 
           [0039]      FIG. 6  shows a perspective view of the same cover to be joined to the box in  FIG. 5 , the cover being shown in an overturned position; 
           [0040]      FIG. 7  shows a perspective view of the slider and its hook for activating the cushioning phase, to be placed on the left-hand side of the bottom of the box in  FIG. 4 , as shown assembled in  FIG. 5 ; 
           [0041]      FIG. 8  shows a perspective view of the slider and its hook for activating the cushioning phase, to be placed on the right-hand side of the bottom of the box in  FIG. 4 , as shown assembled in  FIG. 5 ; 
           [0042]      FIG. 9  shows a perspective view of the two left and right sliders, as per  FIGS. 7 and 8 , as well as their activation hooks, shown pulling apart the double elastic device that joins them; 
           [0043]      FIG. 10  shows a view, from below, of the box in  FIGS. 4 and 5 , joined to the parts hooking onto the fixed points activating the cushioning device in question, shown for illustration purposes with the activation hooks at the maximum distance apart; 
           [0044]      FIG. 11  shows a plan view of an item of furniture with two voids, with both shutters enclosing the corresponding void, highlighting the position of the cushioning box in  FIG. 5  applied to one of the two shutters; 
           [0045]      FIG. 12  shows a magnified plan view of the operating condition of the cushioning box in  FIG. 11 ; 
           [0046]      FIG. 13  shows a plan view corresponding to the view in  FIG. 11 , but with one shutter in its manual translation phase, having overcome the initial cushioning phase and before the final cushioning, for the full opening of its void; 
           [0047]      FIG. 14  shows a magnified plan view of the operating condition of the cushioning box in  FIG. 13 ; 
           [0048]      FIG. 15  shows a plan view of the same item of furniture in  FIG. 11 , with one shutter in its final cushioned opening stage, highlighting the position of its cushioning box as per  FIGS. 4 and 5 ; 
           [0049]      FIG. 16  shows a magnified plan view of the condition of the cushioning box as per  FIG. 15 ; 
       
    
    
       [0050]    All the figures are understood to show the same details with the same reference numbers. 
       DETAILED DESCRIPTION 
       [0051]    According to the structural solution shown for illustration purposes in the various figures, an improved device for cushioning the opening and closing movement of sliding shutters, is essentially made up of a cushioning box  20 , to be applied to one of brackets  1  or  2  that are fixed to an upper edge of a sliding shutter  3 , whose smoothness is ensured by corresponding idler sliding wheels  4  and  5  running along a same track  6 , which is integral to a base plate  12  being mounted on an upper surface  7  of a void  8  that should be able to be opened or closed with said shutter  3 , as schematically shown in  FIGS. 3 and 4 . 
         [0052]    Again in accordance with the solution illustrated, the same  FIGS. 3-4  show that this cushioning box  20 , as well as being integral from one end of the bracket  1  is also fixed to the edge of the sliding shutter  3  by a second bracket  9 , whilst at the upper surface  7  a second track  6 ′ is also applied, integral to the base plate  12 , for the cushioned movement of other sliding doors. 
         [0053]    According to a traditional technique, the sliding wheels  4  and  5  are fixed to the corresponding brackets  1  and  2 , respectively, by the interposition of each a corresponding plate  10  and  11 , respectively, for adjusting the height and verticality of each shutter  3 , whilst the base plate  12 , from which the tracks  6  and  6 ′ emerge and which is fixed to the upper surface  7 , for example by means of screws  16 , has a convenient auxiliary wall  13 , that hides the tracks  6  and  6 ′ from view, and an auxiliary wall  14  that acts as a rib to strengthen the base  12 . 
         [0054]    Naturally the support brackets  1 - 2  and the regulation plates  10 ,  11  on the sliding wheels  4 ,  5  can be designed in various forms, including those already on the market, whilst not being innovations of the present solution which is instead given by the box  20  and by its attachments described below. This box  20  is able to act on both sides of the shutter  3 , cushioning a final travel section, when the void is both opened and closed  8 . 
         [0055]    With reference to  FIG. 5 , the cushioning box  20  is made up of a box shaped-base (structured box base)  21  and a cover  30 , which enclose and guide a pair of opposing sliders  40  and  50 , joined together by an elastic traction device  60 . Each of these sliders  40 ,  50  has its own viscous fluid rotary braking device  70 ′,  70 ″ acting against the traction of said elastic device  60 . 
         [0056]    In closer detail, the box shaped-base  21  has a special internal void  22  with a longitudinal open lightening slit  23  and a lower open slit  24  with a pair of recessed lateral slots  25  and  26 . The longitudinal open lightening slit  23  is arranged in a lateral wall of the box  20 . The lower open slit  24  is arranged in a bottom wall of the box  20 . The pair of recessed lateral slots  25 ,  26  may lead from the lower open slit  24  or beneath of it into the base  21  of the box  20 . 
         [0057]    There is at least one striker  28  situated in the centre of the longitudinal void  22  of the box  20 , integral with the structured box base  21 , to limit the travel of the opposing sliders  40  and  50  in a direction one to the other. 
         [0058]    The aforementioned lower open slit  24  of the box  20  is closed on one side by the overlapping cover  30  and its guiding wall  31 , by a fixing, for example self-tapping screws passing through slots  32  or openings leading through the wall  31 . 
         [0059]    This cover  30  also has a small lateral side wall  33  being a little shorter than the length of the lower open slit  24 , whilst on its opposite side it has a bar or longitudinal edge  35  on the internal side of which is a toothing of a rack  36 . Especially, as can be seen from  FIG. 6  in mounted position the small lateral side wall  33  extends downwardly from the guiding wall  31 , whilst on its opposite upper side it has the bar or longitudinal edge  35 .  FIG. 6  highlights the fact that the internal side of the cover  30  has a bar  35 , fixed to the same cover, for example with screws, with a toothed lower edge of the rack  36 . 
         [0060]    As already specified, in a seat formed by the void  22  of the box  20  there are a pair of the freely sliding sliders  40  and  50  that have their corresponding viscous fluid braking devices  70 ′ and  70 ″, joined together by the elastic device  60 , and that have their corresponding devices for hooking and unhooking the cushioning action. These sliders  40 ,  50  and their components have been jointly shown as  40 ,  50 . In closer detail, as shown in  FIG. 7 , the slider  40  has an oblong housing  41  containing the viscous fluid braking device  70 ′ with its toothed pinion  71 ′. 
         [0061]    The same slider  40  also has a pair of prongs  42 ,  43  shaped to form a void  44 , linked to a transverse slit  45 , and this is completed by the presence of a through hole  46 , with its end near the prong  42 , which may be of a narrower diameter than its initial part. Especially, the pair of prongs  42 ,  43  is shaped like a “C” having the transverse slit  45  leading from middle of vertical wall of “C” horizontally into the wall in direction to the oblong housing  41 . The through hole  46  leads in an vertical direction and through the transverse slit  45 . 
         [0062]    Similarly, as illustrated in  FIG. 8 , even the slider  50  has an oblong void  51  containing the viscous fluid braking device  70 ′ with its toothed pinion  71 ″, and also has a pair of prongs  52 ,  53  shaped to form a void  54 , linked to a transverse slit  55  and completed by the presence of a through hole  56 , with its end near the prong  52  that is of a narrower diameter than its initial part. 
         [0063]    The through holes  46 ,  56  of the slider  40  and of the slider  50 , respectively, are housed ends  47   a  and  57   a  of hinges  47  and  57 , respectively, under pressure, which join corresponding hooks  48  and  58  to the same sliders  40  and  50 , respectively. 
         [0064]    Given that said sliders  40  and  50  are mounted in the void  22  of the box  20 , whilst the hooks  48  and  58  must be external in order to encounter striker pins  80 , which control their operation, a collar  48   a,    58   a  is joined to the same hooks  48 ,  58 , acting as a spacer, vis-á-vis the corresponding sliders  40 ,  50  and as a guide along the lower open slit  24  of the box  20 . The hooks  48 ,  58  are roughly cylindrical, with an axial perforated collar  48   a,    58   a  and a parallel through hole  48   b,    58   b,  as well as a crook  48   c,    58   c  opposite a housing  48   d,    58   d  of a fork, as shown in  FIGS. 7 ,  8  and  10 . 
         [0065]    A safety precaution, for the operation of the hooks  48 ,  58  is again illustrated in  FIGS. 7 ,  8  and  10 , but will be specified in more detail below. 
         [0066]    As already mentioned, cavities formed by the voids  44  and  54  of the sliders  40  and  50 , respectively, are used to house the ends of the elastic traction device  60  that joins the same two sliders  40  and  50  counteracting the braking action of the two braking devices  70 ′ and  70 ″, as detailed in  FIGS. 5 and 9 , which show that said elastic device  60  is innovatively made up of a double concentric helical spring  61 ,  64 , made out of particularly elastic material, so that, when tensioned, the effort required is not excessively variable, because it is the sum of two reactions that are weak or in any case do not exceed the braking action of the devices  70 ′ and  70 ″. 
         [0067]    In particular, the external spring  61  has eyelet shaped ends  62  and  63 , just as the internal spring  64  has eyelet shaped ends  65  and  66 . The second eyelet  65  of the internal spring  64  may be internal to and concentric with the first eyelet  62  of the external spring  61 , whilst first eyelet  66  of the internal spring  64  is internal to and concentric with second eyelet  63  of the external spring  61  or vice versa. After housing the one pair of spring eyelets  63 ,  66  in the slit  45  of the slider  40  and by housing the other pair of spring eyelets  62 ,  65  of the traction springs  61 ,  64  in the slit  55  of the other slider  50 , the hinges  47  and  57  can then be inserted in the holes  46  and  56  to fix the eyelets  62 ,  63 ,  65 ,  66  in the corresponding slits  45 ,  55 . The hinges  47  and  57  are inserted into the holes  46  and  56  after having inserted the hooks  48  and  58  from the especially lower outside of the box  20 , in order to achieve the elasticised union of the same sliders  40  and  50 , allowing their minimum and maximum traction, inside the void  22  of the box  20 , as highlighted in  FIGS. 5 and 9 . Thus, the hooks  48  and  58  are turnable in a plane perpendicular to the hinges  47  and  57 . 
         [0068]    Naturally, before joining the two sliders  40  and  50  with the elastic device  60 , the braking device  70 ′ is placed in its housing  41  of the one of the sliders  40 , and the other braking device  70 ″ is housed in the void or oblong housing  51  of the other slider  50 . 
         [0069]    The cover  30  placed on to the box shaped-base  21 , already equipped with its sliders  40  and  50  and with the other parts described up to now, allows the meshing of the toothing of the hubs formed as toothed pinions  71 ′ and  71 ″ of the braking devices  70 ′ and  70 ″ with the toothing of the rack  36  of the especially laterally extending bar or edge  35 . 
         [0070]    By acting on the hook  48 , for example, it is possible to draw the slider  40  towards the left-hand edge of the housing  22 , unblocking the mesh of the toothed pinion  71 ′ from the rack  36  and also drawing the slider  50  until it strikes against the striker  28 , without substantially stressing the elastic device  60 . By continuing the manual drawing of the slider  40 , it can be taken up to the left-hand lateral edge of the box  20 , overcoming the force of the traction springs  61 ,  64 , which, with the cessation of the drawing effort, react and tend to bring the slider  40  itself towards the centre of the housing  22 , encountering the resistance of the braking device  70 ′ which thus cushions the reaction of the elastic device  60 . Similarly the elastic device  60  is cushioned by acting on the slider  50  after having drawn it towards the right-hand edge of the void  22  itself. 
         [0071]    The box  20 , essentially assembled with the components described up to now, is attached to the shutter  3 , for example using the brackets  1  and  9 , as mentioned in  FIG. 4 , and is therefore forced to translate along the track  6 , until one of its hooks  48  or  58  encounters one of the strikers  80 - 80 ′ placed at the beginning and end of the travel section for the translation of the shutter itself  3 , for the opening or closing of the void  8 , determining the beginning or the end of the section for cushioning this travel. 
         [0072]    From the above, it can be inferred that, at the stage of applying the cushioning device  20  to the shutter  3 , the hooking to the corresponding strikers  80  and  80 ′ is not automatic, given that the tension, even above the limits, of the elastic device  60  never allows the hooks  48 ,  58  to encounter said strikers  80 ,  80 ′. 
         [0073]    In order to overcome this aspect and to guarantee the maximum operating safety of the device in question, a first safety hook  90  is applied to one of the sliders  40  and a second safety hook  100  is applied to the other slider  50 . 
         [0074]    With reference to  FIG. 7 , the hook  90  is pivoted with a hinge  91  to the hole  48   b  of the hook  48  and has a hooked part  90   a  with an external slide or raiser  90   b.  A different hinge  92  is housed in a slot  90   c  of the safety hook  90 , presenting an opposite end  92   a  that can slide along a slot  93   a  made on the bottom of a guide block  93 , and wound around by an elastic spiral  94 , with an arm  94   a  striking against a cylindrical part  90   d  of the safety hook  90 . Especially, the hinge  91  extends through the cylindrical part  90   d  of the safety hook  90 . The hinges  91 ,  92  extend in a vertical direction having their axes in parallel and distanced one to the other. 
         [0075]    Similarly and with reference to  FIG. 8 , the other safety hook  100  is pivoted with a hinge  101  to the hole  58   b  of the other hook  58  and has a hooked part  100   a  with an external slide or raiser  100   b,  whilst a different hinge  102  is housed in a slot  100   c  of the safety hook  100 , presenting an opposite end  102   a  that can slide along a slot  103   a  made on the bottom of a guide block  103 , wound around by an elastic spiral  104  with an arm  104   a  striking against a cylindrical part  100   d  of the latter safety hook  100 . 
         [0076]    Said safety hooks  90  and  100  are forced to slide, together with their guide blocks  93 ,  103  and together with the ordinary hooks  48 ,  58 , along the lower slit  24  of the box  20 , as highlighted in  FIG. 10 . 
         [0077]    The same  FIG. 10  shows that with the translation of the box  20 , following the translation of the shutter  3  to which it is integrally fixed for example by means of the bracket  1 , the hooks  48  and  58 , are freed from the striker  80 ,  80 ′ that remains fixed, but are pushed by these to rotate on their hinge  47 ,  57 , translating in their housings  48   d,    58   d  and being brought to be housed in voids formed by the lateral slots  25  and  26  at the ends of the lower open slit  24  of the box  20 . 
         [0078]    When these hooks  48 ,  58  are housed in said corresponding slots  25 ,  26  the elastic device  60  remains under tension but cannot unblock them, until the same hooks  48 ,  58 , are forced to rotate on their hinge  47 ,  57 , due to their fork housing  48   d,    58   d  newly encountering a striker  80  or  80 ′, along the path for the manual drawing of the travelling shutter  3 . 
         [0079]    When hook  48  or  58  is freed at the blocking position in the recesses  25 ,  26  of the slit  24 , the elastic device  60  reacts and tends to rapidly bring the corresponding slider  40  or  50  back to the centre of the void  22 , until it possibly encounters the striker  28  of the box  20 . Opposing this reaction of the elastic device  60  are the braking devices  70 ′ and  70 ″, present on the sliders  40  and  50 , thus achieving, with a single device formed by the box  20 , the desired cushioning of the final travel for the opening and closing of the shutter  3  on the void  8 , in accordance with the main aim proposed. 
         [0080]    The presence of the crooks  48   c  and  58   c  of the hooks  48  and  58 , respectively, enables a second simultaneous or alternative form of blocking of the same hooks  48 ,  58  in their maximum opening position as in  FIG. 9 . In fact, with the rotation of these hooks  48 ,  58 , caused by their forks  48   d,    58   d  passing onto the fixed strikers  80 ,  80 ′, together with their housing in the voids  25  and  26  of the box  20 , there is also a hooking of their crooks  48   c,    58   c  to the ends of the small side wall  33  of the cover  30 , whilst their freeing is ensured by the rotation of the same hooks  48 ,  58 , due to a subsequent passage of their fork housings  48   d,    58   d  onto the fixed strikers  80 ,  80 ′. 
         [0081]    As mentioned above, during initial installation or when forcibly removing the shutter  3 , the hooking of the forks  48   d,    58   d  to one or both fixed strikers  80 ,  80 ′ is not automatic, which is why the safety hooks  90  and  100  are provided, as already described. 
         [0082]    During the translation of the shutter  3  towards the opening and closing ends of the void  8 , the inclined or raised ends formed by the raisers  90   b  and  100   b  of the safety hooks  90 - 100 , respectively, encounter the strikers  80 ,  80 ′ and are forced to lift, rotating on their hinge  90   d,    100   d,  with a rotation regulated by pegs formed by the other hinges  92 ,  102  of the safety hooks  90 ,  100  within the slits or slots  93   a,    103   a  of the corresponding guide blocks  93 ,  103 , as can be seen from  FIG. 10 . 
         [0083]    Their rotation is also regulated by the springs  94 ,  104  for which, having overcome the obstacle of the fixed strikers  80 ,  80 ′, the springs cause the same safety hooks  90 ,  100  to lower and bring the same strikers  80 ,  80 ′ to be housed in their crook  90   a,    100   a,  drawing them, together with their sliders  40 ,  50  and their corresponding hooks  48 ,  58 , along the lower slit  24 , until the same hooks  48 ,  58  encounter a new striker  80 ,  80 ′ onto which to hook, for the normal activation of the cushioning phase already illustrated above. 
         [0084]    Having thus described the main parts making up the present innovative device for cushioning the final movement of a shutter  3 , when opening and closing a void  8 , as well as of the accessory parts to which the same device can be applied, the operation is summarised below, particularly with the aid of  FIGS. 11 to 16  on which, for simplicity of graphical representation, the tracks  6 ,  6 ′ and the other parts that can be identified by  FIGS. 3 and 4  have not been shown. 
         [0085]      FIGS. 11 and 12  highlight the position and the condition of the box  20  attached to the shutter  3 , when the shutter itself  3  is in a normal closing position on the void  8 , just as the shutter  3 ′ is normally closed on the void  8 ′. In this closing position, the first hook  48  is stopped by the striker  80  that determines the stability of this condition, whilst the second hook  58  is still housed and blocked in the housing formed of the recessed lateral slot  26  of the lower slit  24 , with the elastic device  60  in a position of minimum traction on the hook  48 . Starting the manual pushing of the shutter  3 , to open the void  8 , the box  20  also advances with the shutter  3 , to which it is fixed by the brackets  1  and  9 , with a consequent increase in the traction of the elastic device  60  on the first slider  40  and on its hook  48 , whilst the braking action of the device  70 ′, which is incorporated into the same slider  40 , slows down and delays the unhooking of the slider  40  from the striker  80 . 
         [0086]    The high elasticity of the springs  61  and  64  whose sum of action allows for a uniform distribution of the reaction to the manual pushing of the shutter  3 , relates to the prescribed braking force of the braking devices  70 ′ and  70 ″, so as to determine the correct longitudinal position of the strikers  80  and  80 ′ along the tracks  6  for the idler wheels  4  and  5  for the translation of the shutter  3 . The strikers  80 ,  80 ′ are positioned in striker tracks being arranged in parallel to the tracks  6 ,  6 ′ on the upper side of the base plate  12 . 
         [0087]      FIGS. 11-13  and  15 , together with strikers  80 ,  80 ′, also show strikers  81 ,  81 ′ and must be understood to be either side of the track  6 ′, for the cushioned translation of the shutter  3 ′, which is supported by different brackets  1 ′,  2 ′ and has another identical cushioning box  20 ′ which it was not deemed necessary to show. 
         [0088]    Continuing the manual traction of the shutter  3  and also the braking action of the braking device  70 ′ of the first slider  40 , the hook  48  remains engaged with the striker  80  until the advancement of the box  20  brings the housing formed by the corresponding lateral slot  25  in line with the same hook  48  which remains housed in it, and, rotating on its hinge  47 , frees itself of said striker  80 . In this situation, the initial cushioning action on the opening shutter  3  stops, whilst the manual pushing action continues, towards the full opening of the void  8 , with the hook  48  housed in the void formed by the first lateral slot  25  and the other hook  58  housed in the opposite void formed by the other, second lateral slot  26 , at the two ends of the lower slit  24  and therefore with the elastic device  60  constantly tense, as shown in  FIG. 10  and in  FIGS. 13 and 14 . 
         [0089]      FIGS. 15 and 16 , highlight the fact that, continuing along the direction that opens the shutter  3  and its cushioning box  20 , the other hook  58  encounters the other striker  80 ′ and embeds itself with its housing  58   d,  lifting up from the recess or housing  26  and starting the final cushioning phase, in view of the arrival of the shutter  3  in its full opening position on the void  8 . 
         [0090]    In fact, the braking device  70 ″, integral to the slider  50  and to the other, second hook  58 , brakes the reaction of the elastic device  60  and of any residual manual thrust acting on the shutter  3 , slowing and regulating its final travel, until the other striker  80 ′ encounters the first hook  48  and remains entrapped, within its housing  48   d,  to ensure the stability of the condition of full opening of the void  8 . Naturally, when closing the void  8  again, it is sufficient to appropriately draw the shutter  3 , in order to unblock the first hook  48  from the other striker  80 ′, inverting the phases described so far in order to allow the desired cushioning action when closing the same void  8 . 
         [0091]    From all this, it is clear that, with a single cushioning box, it is possible to regulate the travel of a shutter, when both opening and closing a void, in accordance with the main aim proposed. 
         [0092]    The hooking of the two high elasticity spiralled springs  61  and  64  enables the elastic device  60  to react uniformly to the action of the braking devices  70 ′ and  70 ″, without having to apply boxes that are excessively long or that have blocking devices that distribute their force, consistent with yet another of the specific aims. 
         [0093]    The cushioning box  20 , complete with its attachments described above, can be joined to one of the brackets  1 ,  2  of each type that must be applied for the shutter  3  to slide, or else it can be applied to each type of bracket, as well as to any of its own brackets  9 , making itself in fact universal and applicable to any sliding shutters, consistent with yet another of the specific aims. 
         [0094]    The same cushioning box  20  also eliminates all the problems of extraordinary or scheduled maintenance due to the use of piston cushioning, consistent with yet another of the specific aims. 
         [0095]    Naturally, the structural solution described so far for illustration purposes, can also be designed in other structural forms, initially with the possibility of associating three or four shutters, adequately extending the tracks  6 ,  6 ′ and equipping them with further strikers  80 ,  81 , suitably mounted on the upper surface  7  or on the base plate  12 , just as the same improved device  20  can be used for a plurality of shutters or movable walls, again with the possibility of being applied as a single item for cushioning the final travel for opening and closing each mobile shutter or wall. 
         [0096]    Similarly, it is possible to replace the pair of spiralled springs  61 ,  64  with another elastic device  60  capable of having a corresponding effect on the uniformity and constancy of the reaction to the braking action of the braking devices  70 ′ and  70 ″, just as it is possible to invert the layout of the box  20 , by adjusting the position of the strikers  80 ,  80 ′ and  81 ,  81 ′. 
         [0097]    As already mentioned, it is also possible to ensure the blocking of the hooks  48  and  58  acting only on the lateral slots  25  and housings  26  of the lower open slit  24 , just as it is possible to ensure the same blocking just by hooking the crooks  48   c,    58   c  to the ends of the small side wall  33  of the cover  30  or of a corresponding wall of the base of the box  21 , just as the strikers  80 ,  80 ′ and/or  81 ,  81 ′ can be variously arranged on the upper surface  7  of the void  8 ,  8 ′ to be opened or closed. 
         [0098]    These and other corresponding amendments or adjustments are understood in any case to be part of the originality of the subject matter being protected.