ITUD20130043A1 - HIDDEN HINGE WITH AUTOMATIC RETURN DEVICE TOWARDS A CLOSING POSITION - Google Patents

Description

"RETRACTABLE HINGE WITH AUTOMATIC RETURN DEVICE TOWARDS A CLOSED POSITION"

FIELD OF APPLICATION

The present invention refers to a hinge of the so-called retractable or invisible type, because it is not visible from the outside when it is mounted in a window or a piece of furniture, and this is in a closed position. The hinge comprises two hinging groups, articulated together by means of a central articulation pin and hinged on two corresponding containment bodies that can be inserted one into a seat of a fixed structure, such as for example a frame of the window or cabinet, and the other in a seat of a corresponding mobile structure, such as for example a door, a window, a shutter, or a leaf of a window or door or piece of furniture. The hinge allows 180 ° opening of the mobile structure with respect to the fixed structure. Furthermore, the hinge according to the present invention is provided with a device which tends to maintain it, or to automatically return it constantly to a closed position.

STATE OF THE TECHNIQUE

Concealed, or invisible, hinges are known in the sector of doors and windows, i.e. of the type in which, in the closed position, all the elements that compose them are completely inserted inside the frame, or the piece of furniture, on which they are mounted, so they are not visible from the outside.

Known concealed hinges can be substantially divided into three main categories, according to the number of fixed and mobile fulcrums of the kinematic mechanism that allows their movement between a closed position and a position of maximum opening, usually rotated by 180 ° with respect to that closed. The above three categories are: A) that of invisible hinges with 5 fulcrums, 2 of which are sliding, which is schematically represented in figures 1 and la; B) that of the hinges equipped with 6 fulcrums, one of which is sliding, which is schematically represented in figures 2 and 2a; C) that of the hinges with 7 fulcrums, of which four in a fixed position and the other three constrained to move according to the kinematics, which is schematically represented in fig. 3.

In the following the three aforesaid categories of hinges will also be called, respectively, "5 + 2", "6 + 1" and "7".

It is also known that in each of the aforementioned known hinges it is possible to obtain an automatic return action, i.e. automatic closing, thanks to the application of elastic elements, such as tension springs, torsional springs, leaf springs, or other type, on the elements constituting the kinematic mechanisms of the hinges, which vary according to the type of elastic element used and the type of hinge. In the following, some examples of known solutions to the problem of automatic closing of doors or windows through the use of invisible hinges equipped with elastic elements are illustrated. Furthermore, some possible alternative arrangements of the same will also be illustrated, such as to guarantee the functionality of an automatic return of the hinges, and therefore of the self-closing of the doors on which these devices are to be installed. It is known, for example, to obtain a closing effect with tension springs. With reference to a "5 + 2" configuration (Figures 1 and la), a traction spring, acting between each of the sliding fulcrums fa and fb and the bottom of the corresponding containment body, exerts an action opposite to that which allows the sliding of the same fulcrums fa and fb starting from the closed position, represented in figure 1. For this reason, the tension springs have a closing effect on the hinge and therefore on the corresponding moving part, for example a door, or a window, of a window or a piece of furniture.

Examples of the above known application are described in the United States patent US-A-3,004,280 and in the European patent application EP-A-0352912.

Even in a "6 + 1" type hinge (figures 2 and 2a) it is possible to obtain a closing effect by means of a tension spring, which opposes the translation of the fulcrum fb. An example of a hinge of the "6 + 1" type is described in the European patent application No. 12188173.4 of the Applicants.

Torsional springs have also been widely used to obtain the automatic return function in hinges, especially in the "not invisible" ones, as described for example in US patent US-A-1,892,584. Torsional springs can also be used for the same purpose in invisible hinges. For example, with reference to a hinge of category "5 + 2", one or more torsional springs can be inserted to exploit the rotation of one of the two fixed fulcrums fc and fd (figures 1 and la). These torsional springs, with a shank integral with the rotating elements and one inserted in the hinge housing, tend to exert a moment opposite to that which opens the hinge.

Another possibility of applying torsional springs is that for which the two ends of the spring are made integral with the two arms that make up the kinematic mechanism of the hinge, with the spring coaxial to the central fulcrum f and of the hinge, as indicated in figures l and . Also in this case a torsional spring would exert a moment opposite to that which opens the hinge.

As regards a "6 + 1" category hinge (figures 2 and 2a), a torsional spring can be applied in correspondence with the three fixed fulcrums fc, fd and ff, acting between a rotating arm and the containment body of the hinge , or in correspondence with the central fulcrum fe, acting thanks to the relative rotation of the two arms. Furthermore, it is conceivable to insert a torsional spring at the fulcrum that connects the crank lever to the relative arm of the kinematic mechanism.

Finally, as regards category "7" hinges (fig. 3), a torsional spring can be inserted in correspondence with one of the four fixed fulcrums fc, fd, ff and fg with respect to the containment bodies, in correspondence with the central fulcrum fe, or again in one of the two fulcrums fa and fb which articulate the arms of the kinematics.

Leaf springs are another elastic element potentially capable of exerting a closing action. Their application is possible in all three above categories of hinges. The only difference with respect to the solutions analyzed previously is that for the application of the leaf springs it is necessary that the profile of the rotating body is suitably profiled to exert the compression action on the spring itself, mounted in contact on a or more faces of the hinge containment bodies.

However, the known hinges described above all have at least the following drawback. Whatever the type of spring used, in proximity to the hinge closing position, ie with an opening angle close to 0 °, the force exerted by the spring is minimal. In other words, for low opening angles any spring exerts an action only equal to that of a possible preload of the spring itself. This means that, in the event of high preload, it is possible to have an effective closing action, at the expense of a high effort required to open the hinge, greater assembly complexity and greater loads. Conversely, with low preloads, it is easier to open the hinge, there is also a reduction in technical complexity, but the closing action loses its effectiveness.

An object of the present invention is to provide a retractable hinge which is provided with an automatic return device towards a closing position of the hinge and that this automatic return device is simple, reliable and inexpensive.

Another object of the present invention is to provide a retractable hinge which is provided with an automatic return device which on the one hand ensures a good maintenance of the hinge itself in the closed position, and which on the other hand does not require the user to exert a high effort to move from the closed position to any open position, with a rotation from a few degrees up to 180 ° with respect to the closed position.

To obviate the drawbacks of the known art and to obtain these and further objects and advantages, the Applicants have studied, tested and implemented the present invention.

EXPOSURE OF THE FOUND

The present invention is expressed and characterized in the independent claim.

The dependent claims disclose other characteristics of the present invention.

In accordance with the aforementioned purposes, a retractable hinge according to the present invention, for door and window frames, or furniture, having a movable structure articulated with respect to a fixed structure, comprises two containment bodies hollow internally and suitable to be associated one with the fixed structure and the other to the mobile structure, or vice versa. A hinging mechanism is arranged inside the two containment bodies, in an articulated way with respect to them. At least one elastic element is associated with the aforementioned kinematic mechanism to apply a force on the latter tending to bring the aforesaid two containment bodies back to a closed position.

According to a characteristic aspect of the present invention, at least one magnetic element is provided either inside at least one of the aforementioned containment bodies, or directly on the other containment body, and acting on at least one of the moving parts that make up the aforementioned kinematic mechanism , to help maintain, or bring back, the two containment bodies in their closed position.

According to another characteristic aspect of the present invention, the aforesaid magnetic element comprises a magnet, installed in contact with a wall of one of the containment bodies.

The use of a magnetic element introduces, in fact, an additional force precisely in the operating field in which the action of the elastic element is most lacking, bones for small opening angles of the hinge, without burdening the force necessary to open it. This is due to the fact that the force exerted by a magnetic element on a metal body decreases in a quadratic manner with the distance of the body itself. For this reason, once the opening of the hinge has begun, the magnetic element does not induce additional work to the user due to the rapid decay of its action with increasing distance.

It is possible to insert magnetic elements in all three categories of hinges described above, namely "5 + 2", "6 + 1" and "7".

The magnetic elements, located for example on the bottom of the containment bodies, can exert a recall action both on the translating parts, as in the "5 + 2" hinge, or in the sliding pin of the "6 + 1" hinge, and on the levers with crank in rotary motion, as in the kinematics of the "6 + 1" or "7" hinges.

ILLUSTRATION OF DRAWINGS

These and other characteristics of the present invention will become clear from the following description of preferential embodiments, provided by way of non-limiting example, with reference to the attached drawings in which:

- fig. 1 is a schematic and plan view of a concealed hinge according to the known art, of type A, ie of the "5 + 2" type, in the closed position;

- fig. la is a schematic and plan view of the hinge of fig. 1 in a 90 ° opening position;

- fig. 2 is a schematic and plan view of a concealed hinge according to the known art, of type B, ie of the "6 + 1" type, in the closed position;

- fig. 2a is a schematic and plan view of the hinge of fig. 2 in an open position

- fig. 3 is a schematic and plan view of a concealed hinge according to the known art, of type C, ie of type "7", in the closed position; - fig. 4 is a schematic front view of a concealed hinge according to the present invention, of the "5 + 2" type, in the closed position;

- fig. 5 is a section along the line V-V of fig. 4;

- fig. 6 is an axonometric view of the hinge of fig. 4, in an open position at 90 °;

- fig. 7 is a front view of the hinge of fig. 6;

- fig. 8 is a section along the line VIII-VIII of fig. 7;

- fig. 9 is an axonometric view of the hinge of fig. 4, in a position of maximum opening at 180 °;

- fig. 10 is a front view of the hinge of fig. 9;

- fig. 11 is a section along the line XI-XI of fig. 10;

- fig. 12 is a schematic front view of a retractable hinge according to the present invention, of the "6 + 1" type, in the closed position;

- fig. 13 is a section along the line XIII-XIII of fig. 12;

- fig. 14 is an axonometric view of the hinge of fig. 12, in an open position at 90 °; - fig. 15 is a front view of the hinge of fig. 14;

- fig. 16 is a section along the line XVI-XVI of fig. 15;

- fig. 17 is an axonometric view of the hinge of fig. 12, in a position of maximum opening at 180 °;

- fig. 18 is a front view of the hinge of fig. 17;

- fig. 19 is a section along the line XIX-XIX of fig. 18;

- fig. 20 is a schematic front view of a retractable hinge according to the present invention, of the type "7", in the closed position;

- fig. 21 is a section along the line XXI-XXI of fig. 20;

- fig. 22 is an axonometric view of the hinge of fig. 20, in an open position at 90 °; - fig. 23 is a front view of the hinge of fig. 22;

- fig. 24 is a section along the line XXIV-XXIV of fig. 23;

- fig. 25 is an axonometric view of the hinge of fig. 20, in a position of maximum opening at 180 °;

- fig. 26 is a front view of the hinge of fig. 25;

- fig. 27 is a section along the line XXVII-XXVII of fig. 26.

To facilitate the understanding of the present invention, identical reference numbers have been used, where possible, to identify identical or similar common elements in the different embodiments. It should be understood that elements and features of one embodiment can be conveniently incorporated into other embodiments without further specification.

DESCRIPTION OF THREE PREFERENTIAL FORMS OF

REALIZATION

Figures 4 to 11 show schematically, but in a way that is sufficiently clear and complete for a person skilled in the art to make it, a hinge 10, of the retractable type, according to the present invention, in accordance with a first embodiment , of the "5 + 2" type.

The hinge 10 comprises two containment bodies 11 and 12, internally hollow and suitable to be associated one with a fixed structure and the other with a movable structure of a window or cabinet, or vice versa. A hinging mechanism 13, of a known type and therefore not described in detail, is arranged inside the two containment bodies 11 and 12, in an articulated manner with respect to them. The hinging mechanism 13 comprises five fulcrums 14a, 14b, 14c, 14d and 14e. The fulcrums 14a and 14b slide on pairs of straight grooves 15 obtained on the two containment bodies 11 and 12. The fulcrums 14c and 14d are fixed, while the fulcrum 14e acts as the central fulcrum of the hinging mechanism 13.

A pair of torsional springs 16, which act as elastic elements, are arranged helically around the fixed fulcrum 14d and constantly apply on the latter a force which tends to maintain, or bring back, the two containment bodies 11 and 12, and therefore the hinge 10, in the closed position, shown in Figures 4 and 5.

A magnet 17 is mounted in the containment body 11, for example on one of its internal walls, so as to cooperate with the sliding fulcrum 14a and in particular to attract it towards itself, until it contacts it, when the hinge 10 is in closed position. According to a variant not shown in the drawings, but easily understood by a person skilled in the art, a ferromagnetic element can be associated with the sliding fulcrum 14a, so that the magnet 17 will directly contact the latter, instead of the sliding fulcrum 14a.

The action of the magnet 17 increases in entity in quadratic ratio as the sliding fulcrum 14a approaches it. Therefore, since the minimum distance occurs in conditions of the hinge 10 almost closed, the magnet 17 will exert the maximum action precisely for low opening angles of the hinge 10, ie when the action of the torsional spring 16 is less effective.

When the hinge 10 is in the open positions, and in particular in those from 90 ° to 180 °, represented in figures 5 to 8 and, respectively, 9 to 11, the action of the magnet 17 loses its effectiveness, but increases that of the torsional springs 16.

Figures 12 to 19 show schematically, but in a way that is sufficiently clear and complete for a person skilled in the art to make it, a hinge 110, of the retractable type, according to the present invention, in accordance with a second embodiment , of the "6 + 1" type. The hinge 110 is similar to that described in the Applicants' European patent application No. 12188173.4, which is referred to here by reference.

Compared to the hinge 10 described above, the hinge 110 has the following differences.

The fulcrum 14a, instead of sliding, is hinged at the end of a crank lever 18, which is in turn hinged on a fixed fulcrum 14f mounted on the containment body 11.

Only the fulcrum 14b slides on a pair of grooves 15 obtained on the containment body 12, which are curved instead of straight.

The pair of torsional springs 16 is arranged in a helix around the fixed fulcrum 14f.

The magnet 17 is mounted in the containment body 11 in such a way as to cooperate with the crank lever 18 and in particular to attract it towards you, even to contact it, when the hinge 110 is in the closed position (figures 12 and 13 ). According to a variant not shown in the drawings, but easily understood by a person skilled in the art, a ferromagnetic element can be associated with the crank lever 18, so that the magnet 17 will directly contact the latter, instead of the crank lever 18. Similarly to the hinge 10, when the hinge 110 is in the open positions, and in particular in those from 90 ° to 180 °, represented in figures 14 to 16 and, respectively, 17 to 19, the action of the magnet 17 loses effectiveness, but that of the torsional springs increases 16.

Figures 20 to 27 show schematically, but in a way that is sufficiently clear and complete for a person skilled in the art to make it, a hinge 210, of the retractable type, according to the present invention, in accordance with a third embodiment , of the type "7".

Compared to the hinge 10 described above, the hinge 210 has the following differences.

The fulcrums 14a and 14b, instead of sliding, are each hinged at the end of an arm 19, respectively 20, of the hinging mechanism 13, which is in turn hinged on a fixed fulcrum 14f mounted on the containment body 11 , respectively 14g, mounted on the containment body 12.

The pair of torsional springs 16 is arranged in a helix around the fixed fulcrum 14g.

The magnet 17 is mounted in the containment body 11 so as to cooperate with the arm 19 and in particular to attract it towards itself, until it contacts it, when the hinge 210 is in the closed position (figures 20 and 21). According to a variant not shown in the drawings, but easily understood by a person skilled in the art, a ferromagnetic element can be associated with the arm 19, so that the magnet 17 will directly contact the latter, instead of the arm 19.

Similarly to hinges 10 and 110, when the hinge 210 is in the opening positions, and in particular in those from 90 ° to 180 °, shown in figures 22 to 24 and, respectively, 25 to 27, the action of the magnet 17 loses its effectiveness, but that of the torsional springs 16 increases.

From the above description it is clear that the concealed hinges 10, 110, 210 comprise at least one elastic element (torsional springs 16) associated with the hinging mechanism 13 to apply to the latter a force tending to maintain, or to bring back, the two bodies of containment 11 and 12 in a closed position, and that at least one magnetic element (magnet 17) is provided inside at least one of the containment bodies 11 and 12 and acts on at least one of the moving parts (sliding fulcrum 14a, lever crank 18, or arm 19) which make up the hinging mechanism 13, to help maintain, or bring back, the two containment bodies 11 and 12 in the closed position.

It is understood that modifications and / or additions of parts may be made to the hinges 10, 110, 210 described up to now, without thereby departing from the scope of the present invention.

For example, other torsional springs, or traction springs, or even leaf springs, can be provided in addition to, or in place of, the torsional springs 16, as explained in the part relating to the state of the art.

Furthermore, adjustment members can be provided which allow the reciprocal adjustment of the two containment bodies 11 and 12.

In addition, devices for adjusting the position of the magnetic element 17 can also be provided, so as to be able to move it away from, or bring it closer to, the sliding fulcrum 14a, the crank lever 18, or the arm 19.

It is also clear that, although the present invention has been described with reference to some specific examples, a person skilled in the art will certainly be able to realize many other equivalent forms of concealed hinges having the characteristics expressed in the claims and therefore all falling within the scope protection defined by them.

Claims (9)

CLAIMS 1. Concealed hinge comprising two containment bodies (11, 12) hollow internally and suitable to be associated one with a fixed structure and the other with a mobile structure, or vice versa, a hinging mechanism (13) arranged inside of said two containment bodies (11, 12), in an articulated manner with respect to them, and at least one elastic element (16) associated with said hinging mechanism (13) to apply to the latter a force tending to maintain, or to bring , said two containment bodies (11, 12) in a closed position, characterized by the fact that at least one magnetic element (17) is provided either inside at least one of said containment bodies (11, 12), or directly on the other containment body (12, 11), and acting on at least one of the moving parts that make up said hinging mechanism (13), to help maintain, or bring back, said two containment bodies (11, 12) in said closed position. 2. Concealed hinge as in claim 1, characterized in that said magnetic element comprises a magnet (17), mounted on a wall of one of the containment bodies (11, 12). 3. Concealed hinge as in claim 1 or 2, characterized in that said elastic element comprises at least one torsional spring (16) arranged helically around a fixed fulcrum (14d, 14f, 14g) of said hinging mechanism (13) . 4. Concealed hinge as in claim 1, 2 or 3, wherein said hinging mechanism (13) comprises two sliding fulcrums (14a, 14b), characterized in that said magnetic element (17) is arranged in a first of said containment bodies (11) to cooperate with a first sliding fulcrum (14a) of said sliding fulcrums (14a, 14b). 5. Concealed hinge as in claim 4, characterized in that said magnetic element (17) is configured to contact said first sliding fulcrum (14a), or a ferromagnetic element integral with it, when said containment bodies (11, 12 ) are in said closed position. 6. Concealed hinge as in claim 1, 2 or 3, wherein said hinging mechanism (13) comprises at least one crank lever (18) hinged on one of said containment bodies (11, 12), characterized in that said magnetic element (17) is arranged in a first (11) of said containment bodies (11, 12) to cooperate with said at least one crank lever (18). 7. Concealed hinge as in claim 6, characterized in that said magnetic element (17) is configured to contact said at least one crank lever (18), or a ferromagnetic element integral with it, when said containment bodies (11 , 12) are in said closed position. 8. Concealed hinge as in claim 1, 2 or 3, in which said hinging mechanism (13) comprises at least two arms (19, 20) each hinged on one of said containment bodies (11, 12), characterized by the fact that said magnetic element (17) is arranged in a first (11) of said containment bodies (11, 12) to cooperate with a first arm (19) of said at least two arms (19, 20). 9. Concealed hinge as in claim 8, characterized in that said magnetic element (17) is configured to contact said first arm (19), or a ferromagnetic element integral with it, when said containment bodies (11, 12) they are in said closed position.