STIFFENING CROSS MEMBER FOR NON-LOAD BEARING BUILDING STRUCTURES

Abstract

 Stiffening cross member (R1, R2) suitable for being mounted astride two profiles (3) disposed in opposite and parallel position; wherein the stiffening cross member (R1, R2) comprises two brackets (1) suitable for being connected to the two opposite profiles (3), and a connection profile (2) connected to both brackets (1); the peculiarity of the stiffening cross member (R1, R2) is that each bracket (1) comprises a coupling body (10) configured in such a way to be elastically compressed to pass through a narrowed mouth (30a) of the profile and be elastically fitted into the profile.

Description

[0001] The patent application for industrial invention relates to a stiffening cross member for non-load bearing building structures.

[0002] The present patent application has been devised for application in the field of non-load bearing building structures, such as frames of partition walls, supporting frame of false ceilings or frames of trapdoors.

[0003] In particular, the present invention has been devised in the field of inspection trapdoors that are usually installed in correspondence with openings formed in walls in such a way as to allow for the inspection of a compartment disposed behind the wall. It should be noted that in the present description the term "wall" refers indifferently to both vertical walls and ceilings or floors.

[0004] Traditionally, an inspection trapdoor comprises:

• a fixed frame suitable for being fixed to the wall in correspondence with an opening of the wall;
• a door arranged internally to said fixed frame and movably connected to said fixed frame so as to be disposed in an opening position and a closing position; the door comprises a supporting frame and a panel fixed to the supporting frame.

[0005] Starting from such a conventional configuration, there has been an evolution over time with reference to how such an inspection trapdoor is fabricated.

[0006] Considering that normally a typical trapdoor has a square profile, in less recent times it has been considered to fabricate the supporting frame of the door by means of four profiles disposed two by two in opposite position, and four corner pieces connecting the adjacent profiles two by two.

[0007] In order to strengthen the frames, one or more stiffening cross members are mounted astride two opposite profiles of the frame and attached to the frame.

[0008] Such stiffening cross members comprise two brackets that support a connection profile at the ends. Each bracket of the stiffening cross member is fixed to the profile of the supporting frame and to one end of the connection profile by means of threaded connection elements, such as screws or bolts.

[0009] The use of threaded connection elements that need to be screwed is a time-consuming and complex operation for the installation of such stiffening cross members.

[0010] In fact, the operator must be equipped with an appropriate tool capable of tightening the threaded connection elements in such a way to mount the stiffening cross member and fasten it to the profiles of the supporting frame.

[0011] In the absence of an automatic screwdriver, the operator will have to use an ordinary screwdriver or an Allen wrench and will need a long time and a great effort to realize the stiffening cross member. Obviously, the operator may significantly reduce the effort and time that are necessary for the installation of the stiffening cross member by using an automatic screwdriver, which is nevertheless characterized by a higher cost and a larger volume compared to those of an ordinary screwdriver or wrench.

[0012] It is evident that the problems that occur in said doors for inspection trapdoors are also encountered in all those applications in which it is necessary to stiffen a structure composed of two profiles disposed in parallel position to each other, such as in the frames of partition walls or in the supporting frames of false ceilings.

[0013] The purpose of the present invention is to overcome the drawbacks of the prior art by devising a stiffening cross member that is simple and quick to mount on two parallel profiles of the supporting frames and does not require the use of threaded connection elements for its installation.

[0014] A further purpose of the present invention is to devise a stiffening cross member that is efficient and robust.

[0015] Another purpose of the present invention is to devise a stiffening cross member that is simple and inexpensive to make.

[0016] These purposes are achieved in accordance with the invention with the features listed in the attached independent claim 1.

[0017] Advantageous achievements appear from the dependent claims.

[0018] The stiffening cross member according to the invention is defined by claim 1.

[0019] For explanatory clarity, the description of the stiffening cross member according to the invention continues with reference to the attached drawings, which are for illustrative and non-limiting purposes only, wherein:

Fig. 1 is a rear view of an inspection trapdoor provided with a door whereon a stiffening cross member according to the invention is attached;

Fig. 1A is a rear view of the door of the inspection trapdoor of Fig. 1;

Fig. 2 is a partial detailed view of a first embodiment of the stiffening cross member according to the invention applied to a door of the inspection trapdoor;

Fig. 3 is an axonometric view of two brackets of the first embodiment of the stiffening cross member shown in Fig. 2;

Fig. 4 is a front view of one of the two brackets shown in Fig. 3;

Figs. 5-5C are diagrammatic step-by-step views of the way in which the stiffening cross member of the first embodiment is connected to two parallel profiles;

Fig. 6 is a partial detailed view of a second embodiment of the stiffening cross member according to the invention applied to a door of an inspection trapdoor;

Fig. 7 is an axonometric view of two brackets of the second embodiment of the stiffening cross member shown in Fig. 6;

Fig. 8 is a front view of one of the two brackets shown in Fig. 7;

Figs. 9-9B are diagrammatic step-by-step views of the way in which the stiffening cross member of the second embodiment is connected to two parallel profiles.

[0020] With reference to Figs. 1-9B, a stiffening cross member according to the invention is described.

[0021] Specifically, two embodiments of the stiffening cross member are shown in the attached figures, namely a first embodiment of the stiffening cross member (R1) shown in Figs. 2-5, and a second embodiment of the stiffening cross member (R2) shown in Figs. 6- 9.

[0022] Referring to Figs. 1 and 1A, the stiffening cross member (R1, R2) according to the invention is applied to a supporting frame (Q) for a panel (P). Specifically, the supporting frame (Q) and the panel (P) define a door (S) of an inspection trapdoor (B).

[0023] Again with reference to Figs. 1 and 1A, the inspection trapdoor (B) comprises a fixed outer frame (H) suitable for being fixed on a wall opening and a door (S) movably mounted relative to the fixed outer frame (H) between an opening position and a closing position. Movable connection means (C) are provided between the fixed outer frame (H) and the door (S) to let the door (S) move relative to the fixed frame (H), whereas locking means (M) are provided to lock the door (S) in closing position relative to the fixed frame (H).

[0024] The general structure of the fixed outer frame (H), of the connection means (C) and of the locking means (M) is considered to be generally known. By way of example, document WO2022167230A1 in the name of the same applicant discloses a conventional inspection trapdoor (B) having the fixed outer frame (H), the connection means (C) and the locking means (M). However, for the realization of said elements, reference can be made to any inspection trapdoor of the prior art.

[0025] On the contrary, only those elements of particular importance and interest for the purposes of the realization of the present invention will be described in detail below.

[0026] With reference to Fig. 1A, the supporting frame (Q) of the door (S) comprises four profiles (3, 3') disposed two by two in opposite parallel position, and four corner pieces (4), each one connecting two adjacent profiles at right angle so as to define a frame.

[0027] Said four profiles (3, 3') comprise two first profiles (3) in opposite parallel position and two second profiles (3') in opposite parallel position.

[0028] Referring to Figs. 1A, 2 and 6, each profile (3, 3') comprises a body (3a) having a C-shaped cross-section and comprising a longitudinal seat (30) that is defined by a bottom wall (31), an inner side (32) facing the other profile (3, 3'), and an outer side (33) opposite and parallel to the inner side (32).

[0029] The sides (32, 33) comprise upper teeth (321, 331) that define a narrowed mouth (30a) of the longitudinal seat (30). The narrowed mouth (30a) is shown in Figs. 5 and 9.

[0030] Referring to Figs. 2 and 6, the bottom wall (31) has a first face (311) facing the longitudinal seat (30) from which said sides (32, 33) protrude, and a second face (312) opposite said first face (311).

[0031] An undercut (35) is provided between the upper tooth (331) of the outer side (33) and the bottom wall (31).

[0032] The panel (P) has a quadrangular shape that corresponds to the shape of the supporting frame (Q), and comprises four side edges (P0), a first face (P1) and a second face (P2). The second face (P2) of the panel is attached, preferably by means of adhesives and the like, to the second faces (312) of the bottom wall (31) of the bodies (3a) of the four profiles (3, 3').

[0033] Preferably, each profile (3, 3') comprises a wing (3b) protruding orthogonally from the second face (312) of the bottom wall (31) of the body (3a) coplanar to the outer side (33) of the body (3a). Each wing (3b) is suitable for covering a corresponding side edge (P0) of the panel (P).

[0034] It should be noted that even if the supporting frame (Q) is shown with four profiles (3, 3') and four corner pieces (4), in alternative embodiments of the invention said frame (Q) may be composed of:

• only two first profiles (3) parallel to each other; or
• a single monolithic frame consisting of the first profiles (3) and of the second profiles (3') that are made in one piece.

[0035] The stiffening cross member (R1, R2) is suitable for being mounted astride two profiles (3, 3') disposed in opposite parallel position.

[0036] Specifically, the stiffening cross member (R1, R2) is mounted astride the first two profiles (3) of the supporting frame (Q).

[0037] The stiffening cross member (R1, R2) comprises two brackets (1) connected to the first two opposite profiles (3) and a connection profile (2) with ends (20) connected to the two brackets (1)

[0038] Referring to Figs. 3, 4, 7 and 8, each bracket (1) comprises:

• a coupling body (10) having a longitudinal axis (Y) suitable for being arranged in parallel position to the profile (3),
• a retention foot (14) that protrudes laterally from the coupling body (10) of the bracket (1) and is suitable for being engaged in the undercut (35) defined by the upper tooth (331) of the outer side (33) of the body (3a) of the profile; and
• connection means (13) that protrude from the body (10) on the opposite side from the side where the retention foot (14) protrudes and that protrude beyond the inner side (32) of the body (3a) of the profile (3).

[0039] The coupling body (10) is suitably configured to be elastically compressed toward the longitudinal axis (Y) so as to let the retention foot (14) approach the connection means (13) until it reaches a position that lets it pass through the narrowed mouth (30a) of the profile along a coupling direction that is orthogonal or incident to the bottom wall (31) and then be elastically fitted into the undercut (35) defined by the upper tooth (331) of the outer side (33) of the body (3a) of the first profile (3).

[0040] In both embodiments of the stiffening cross member (R1, R2), the coupling body (10) of the bracket (1) is hollow with cavity facing the bottom wall (31) of the body (3a) of the first profile (3) and comprises:

• a first leg (11) suitable for resting on the first face (311) of the bottom wall (31) and from which said retention foot (14) protrudes externally;
• a second leg (12) that rests on the first face (311) of the bottom wall (31) and from which the connection means (13) protrude externally.

[0041] The first leg (11) is shaped in such a way to be elastically flexible so that it can approach the second leg (12) to let the retention foot (14) pass beyond the upper tooth (331) of the outer side (33) and be elastically fitted into the undercut (35).

[0042] The retention foot (14) comprises an invitation surface (141) that is configured in such a way to intercept the upper tooth (331) of the outer side (33) of the body (3a) of the profile (3) during the attachment of the bracket (1) to the profile (3), thus favoring the bending of the first leg (11) toward the second leg (12) and letting the retention foot (14) pass beyond the upper tooth (331) of the outer side (33). Preferably, the retention body (10) has a substantially inverted U-shape comprising:

• the first lateral leg (11);
• the second lateral leg (12); and
• a curved section (110) that connects the two lateral legs (11, 12).

[0043] According to the preferred embodiment of the invention, the second lateral leg (12) comprises a first section (121) that is connected to the curved section (110) and from which the connection means (13) protrude, and a second section (122) that is suitable for resting on the bottom wall (31) of the body (3a) of the profile (3).

[0044] The second section (122) can be defined as a supporting appendage for said second lateral leg (12)

[0045] The second section (122) of the second lateral leg (12) does not extend for the entire length of the body (10), as shown in Fig. 7. It should be noted that the length of the coupling body (10) is the extension of the coupling body (10) along its longitudinal axis (Y).

[0046] The coupling body (10) also comprises anti-misalignment means configured so as to firmly maintain the coupling body (10) positioned with its longitudinal axis (Y) parallel to the profile (3) whereto it is attached.

[0047] Said anti-misalignment means comprise surfaces (s1, s2) formed on the first leg (11) and on the second leg (12) of the coupling body (10) that are suitable for abutting against front faces (321a, 331a) of the upper teeth (321, 331) of the two sides (32, 33).

[0048] In particular, said surfaces (s1, s2) comprise first surfaces (s1) that are formed on projections (115) that protrude externally from the first leg (11) and are suitable for abutting against the front face (331a) of the upper tooth (331) of the outer side (33), and a second surface (s2) that is formed on the second section (122) of the second leg (12) and is suitable for abutting against the front face (321a) of the upper tooth (321) of the inner side (32).

[0049] The connection means (13) of each bracket (1) comprise a supporting partition (13a) that protrudes from the second leg (12) and lies in a plane orthogonal to the longitudinal axis (Y) of the coupling body (10) and a connection element (13b) connected to the supporting partition (13a) and suitable for being coupled with the end (20) of the connection profile (2).

[0050] The two embodiments of the stiffening cross member (R1, R2) differ in the type of connection profile (2) and in the connection element (13b) of the connection means (13) of the brackets (1).

[0051] In this regard, the peculiarities that distinguish the first embodiment of the stiffening cross member (R1) and the second embodiment of the stiffening cross member (R2) are described hereinafter.

[0052] With reference to Figs. 2, 3 and 4, in the first embodiment of the stiffening cross member (R1), the connection element (13b) of the connection means (13) of the bracket (1) is boxed and comprises a seat (130) having a front opening that faces the other bracket (1) located in the other profile (3).

[0053] The connection profile (2) has ends (20) inserted in the seat (130).

[0054] The seat (130) is an inverted U-shaped seat that is open at the front opening and also at the bottom.

[0055] In this regard, the connection profile (2) has a substantially T-shaped cross-section and has a first wing (21) inserted into the seat (130) and a second wing (22) orthogonal to the first wing (21) disposed under the seat (130). The second wing (22) is abutting against the second face (P2) of the panel (P).

[0056] In such an embodiment, the bracket (1) comprises two wings (17) arranged laterally to the connection means (13), which are suitable for passing beyond the inner side (32) of the body (3a) of the profile (3). Each wing (17) is joined to the first section (121) of the second leg (12) of the coupling body (10) and extends orthogonally to the first section (121) of the second leg (12). Each wing (17) has an ending edge (17a) that protrudes beyond the inner side (32) of the body (3a) of the profile (3) and from which supporting feet (18) resting on the second wing (22) of the connection profile (2) protrude inferiorly.

[0057] With reference to Figs. 5, 5A, 5B, 5C, the installation of the stiffening cross member (R1) according to the first embodiment provides for:

• arranging the connection profile (2) on the second face (P2) of the panel (P) with the second wing (22) resting on the second face (P2) of the panel (P), as shown in Fig. 5;
• bringing both brackets (1) closer to the first profiles (3), ensuring that the ends (20) of the connection profile (2) are inserted into the seats (130) of the connection elements (13b) of the connection means (13) of the two brackets (1) until the retention feet (14) are brought to a stop above the upper teeth (331) of the outer sides (33) of the two profiles (3), as shown in Fig. 5A;
• imposing a thrust toward the two profiles (3) on both brackets (1) such that the invitation surface (141) of the retention leg (14) of each bracket interferes with the respective upper tooth (331) of the outer side (33) and imposes a bending on the first leg (11) of the coupling body (10) of the bracket toward the second leg (12) of the coupling body (10) of the bracket that lets the retention foot (14) pass beyond the upper teeth (331) of the outer side (33) (see Fig. 5B) and engage in the undercut (35) by firmly engaging the coupling body (10) of the bracket (1) to the respective profile (3) (see Fig. 5C).

[0058] With reference to Fig. 5C, it should be pointed out that the surfaces (s1, s2) of the anti-misalignment means are abutting against the front faces (331a, 321a) of the upper teeth (331, 321) of the sides (33, 32) of the body (1a) in such a way that the bracket (1) cannot be misaligned with respect to the profile.

[0059] With reference to Figs. 6, 7 and 8, according to the second embodiment of the stiffening cross member (R2), the connection element (13b) of the connection means (13) of the bracket (1) comprises a tab (135) that protrudes from the supporting partition (13a).

[0060] In such a case, the connection profile (2) comprises a longitudinal seat (28) extending for the entire length of the connection profile (2), at the ends of which the tabs (135) of the connection means (13) of the two brackets (1) are inserted.

[0061] In such a case, the connection profile (2) is an L-shaped profile and comprises a first wing (25) provided with said longitudinal seat (28), and a second wing (26) that is orthogonal to the first wing (25) and is abutting against the second face (P2) of the panel (P).

[0062] With reference to Figs. 9, 9A and 9B, the installation of the stiffening cross member (R2) according to the second embodiment provides for:

• inserting the tabs (135) of the connection means (13) of the two brackets (1) at the ends of the longitudinal seat (28) of the profile (2) in such a way that the profile (2) is supported at the ends by the two brackets (1);
• positioning the brackets (1) above the two first profiles (3) parallel to each other in such a way that the retention feet (14) of the two brackets (1) rest on top of the upper teeth (331) of the outer sides (33) of the two profiles (3), as shown in Fig. 9;
• imposing a thrust toward the two profiles (3) on both brackets (1) such that the invitation surface (141) of the retention foot (14) of each bracket (1) interferes with the respective upper tooth (331) of the outer sides (33) and imposes a bending on the first leg (11) of the coupling body (10) of the bracket toward the second leg (12) of the coupling body (10) of the bracket that lets the retention foot (14) pass beyond the upper tooth (331) of the outer side (33) (see Fig. 9A) and engage in the undercut (35) by firmly engaging the retention body (10) of the bracket (1) to the respective profile (3) (see Fig. 9B).

[0063] With reference to Fig. 9B, it is worth noting that the surfaces (s1, s2) of the anti-misalignment means are abutting against the front faces (331a, 321a) of the upper tooth (331, 321) of the sides (33, 32) of the body (1a) in such a way that the bracket (1) cannot be misaligned with respect to the profile.

[0064] It should be noted that, although in the attached figures and in the present description the stiffening cross member (R1, R2) is mounted astride two first profiles (3) of a support frame (Q) of a door (S) of an inspection trapdoor (B), obviously the stiffening cross member (R1, R2) can also be mounted with the same advantages astride two profiles of a frame of a non-load bearing structure, such as a frame supporting a panel of a false ceiling or a frame supporting a panel of a vertical insulating or soundproofing wall.

[0065] In all cases where the stiffening cross member (R1, R2) is mounted astride two parallel profiles that support a panel, the stiffening cross member (R1, R2) has the dual function of stiffening both the profiles and the panel.

[0066] In addition, the stiffening cross member (R1, R2) according to the invention is also suitable for being used with the same advantages astride two parallel profiles that do not support any panel. In such a case, in order to stiffen such profiles (31, 32), the second embodiment of the stiffening cross member (R2) will have to be used since the connection profile (3) cannot slip out laterally from the tabs (135) of the connection means (13) of the brackets (1).

[0067] As a result of the above description, it is now apparent that the stiffening cross member (R1, R2) according to the invention is extremely simple and quick to be mounted between two parallel profiles (3). In fact, it is simply necessary to rest the two brackets (1) onto the profiles (3) and then to impose a slight thrust on the two brackets (1) toward the profiles (3) to let the retention feet (14) pass beyond the upper tooth (331) of the outer side (33) and engage into the undercut (35).

[0068] Although in the attached figures the brackets (1) and the connection profile (2) are made in separate pieces and coupled by means of the connection means (13) of the brackets (1), in an alternative version of the invention it is also possible to provide that the brackets (1) and the connection profile (2) are made of plastic material in one monolithic piece.

[0069] Numerous variations and modifications may be made to the present embodiment of the invention, within the scope of a technician of the field and in any case falling withing the scope of the invention as expressed by the appended claims.

Claims

1. Stiffening cross member (R1, R2) suitable for being mounted astride two profiles (3) disposed in parallel position; wherein each profile (3) comprises a body (3a) having a C-shaped cross-section and comprising a longitudinal seat (30) defined by a bottom wall (31), an inner side (32) and an outer side (33) parallel to the inner side (32); the sides (32, 33) comprise upper teeth (321, 331) defining a narrowed mouth (30a) of the longitudinal seat (30); wherein the upper tooth (331) of the outer side (33) defines an undercut (35);

wherein said stiffening cross member (R1, R2) comprises:

- two brackets (1) suitable for being connected to the two opposite profiles (3); and

- a connection profile (2) connected to both brackets (1);

wherein each bracket (1) comprises:

- a coupling body (10) having a longitudinal axis (Y) suitable for being disposed in parallel direction to the profile (3); and

- a retention foot (14) protruding laterally from the coupling body (10) of the bracket (1) and suitable for being engaged in said undercut (35) defined by the upper tooth (331) of the outer side (33) of the body (3a) of the profile; and wherein the coupling body (10) is configured in such a way to be elastically compressed toward its longitudinal axis (Y) so that the retention tooth (14) can reach a position suitable for passing through the narrowed mouth (30a) of the profile along a coupling direction that is orthogonal or incident to the bottom wall (31) of the profile (3) and for being elastically fitted into the undercut (35) defined by the upper tooth (331) of the outer side (33);

wherein the coupling body (10) of the bracket (1) is hollow and comprises:

- a first leg (11), from which said retention foot (14) protrudes externally; and

- a second leg (12);

characterized by the fact that

the coupling body (10) is substantially provided with an inverted U-shape and comprises a curved profile (110) connecting the two legs (11, 12).

2. The stiffening cross member (R1, R2) according to claim 1, wherein the coupling body (10) comprises anti-misalignment means configured in such a way to firmly hold the coupling body (10) disposed with the longitudinal axis (Y) parallel to the profile (3).

3. The stiffening cross member (R1, R2) according to any one of the preceding claims, wherein each bracket (1) comprises connection means (13) which protrude from the coupling body (10) on the side opposite to the side from where the retention foot (14) protrudes and are suitable for protruding beyond the inner side (32) of the body (3a) of the profile (3); wherein said connection profile (2) has ends (20) coupled with said connection means (13) of the two brackets (1).

4. The stiffening cross member (R1, R2) according to claim 3, wherein the connection means (13) of each bracket (1) comprise:

- a supporting partition (13a) protruding from the second leg (12) and lying on a plane orthogonal to the longitudinal axis (Y) of the coupling body (10); and

- a connection element (13b) connected to the supporting partition (13a) and suitable for being coupled with the end (20) of the connection profile (2).

5. Structure comprising:

- two profiles (3) disposed in parallel position; wherein each profile (3) comprises a body (3a) having a C-shaped cross-section and comprising a longitudinal seat (30) defined by a bottom wall (31), an inner side (32), and an outer side (33) parallel to the inner side (32); the sides (32, 33) comprise upper teeth (321, 331) defining a narrowed mouth (30a) of the longitudinal seat (30); wherein the upper tooth (331) of the outer side (33) of the body (3a) of the profile (3) defines an undercut (35); wherein the bottom wall (31) of the body (3a) of the profile (3) has a first face facing the longitudinal seat (30) and a second face (312) opposite to said first face (311);

- a panel (P) having a first face (P1) and a second face (P2) attached to the second faces (312) of the bottom walls (31) of the bodies (3a) of the profiles (3); and

- a stiffening cross member (R1, R2) suitable for being mounted astride the two profiles (3) in opposite parallel position;

wherein said stiffening cross member (R1, R2) comprises:

- two brackets (1) suitable for being connected to the two opposite profiles (3); and

- a connection profile (2) connected to both brackets (1) and abutting against the second face (P2) of the panel (P);

wherein each bracket (1) comprises:

- a coupling body (10) having a longitudinal axis (Y) suitable for being disposed in parallel direction to the profile (3); and

- a retention foot (14) protruding laterally from the coupling body (10) of the bracket (1) and suitable for being engaged in said undercut (35) defined by the upper tooth (331) of the outer side (33) of the body (3a) of the profile;

wherein the coupling body (10) is configured in such a way to be elastically compressed toward its longitudinal axis (Y) so that the retention tooth (14) can reach a position suitable for passing through the narrowed mouth (30a) along a coupling direction that is orthogonal or incident to the bottom wall (31) of the profile (3) and for being elastically fitted into the undercut (35) defined by the upper tooth (331) of the outer side (33).

6. The structure according to claim 5, wherein the coupling body (10) of the bracket (1) is hollow, has an inverted U-shape and comprises:

- a first leg (11), from which said retention foot (14) protrudes externally;

- a second leg (12); and

- a curved section (110) that connects said two legs (11, 12).

7. The structure according to claim 5 or 6, wherein the coupling body (10) comprises anti-misalignment means configured in such a way to firmly hold the coupling body (10) disposed with the longitudinal axis (Y) parallel to the profile (3).

8. The structure according to claim 5 or 6 or 7, wherein each bracket (1) comprises connection means (13) which protrude from the coupling body (10) on the side opposite to the side from where the retention foot (14) protrudes and are suitable for protruding beyond the inner side (32) of the body (3a) of the profile (3); wherein said connection profile (2) has ends (20) coupled with said connection means (13) of the two brackets (1).

9. The structure according to claim 8, when dependent on claim 6, wherein the connection means (13) of each bracket (1) comprise:

- a supporting partition (13a) protruding from the second leg (12) and lying on a plane orthogonal to the longitudinal axis (Y) of the coupling body (10); and

- a connection element (13b) connected to the supporting partition (13a) and suitable for being coupled with the end (20) of the connection profile (2).

10. Door (S) of an access panel (B); said door (S) comprising:

- a supporting frame (Q) comprising two first profiles (3) in opposite and parallel position, two second profiles (3') in parallel position and four corner pieces (4), each one connecting two adjacent profiles at right angle; wherein each profile (3) comprises a body (3a) with a C-shaped cross-section comprising a longitudinal seat (30) defined by a bottom wall (31), an inner side (32) and an outer side (33) opposite and parallel to the inner side (32); the sides (32, 33) comprise upper teeth (321, 331) defining a narrowed mouth (30a) of the longitudinal seat (30); wherein the upper tooth (331) of the outer side (33) defines an undercut (35); wherein the bottom wall (31) of the body (3a) of the profile (3) has a first face (311) facing the longitudinal seat (30) and a second face (312) opposite said first face (311);

- a panel (P) having a first face (P1) and a second face (P2) that is fixed to the second faces (312) of the bottom walls (31) of the bodies (3a) of the profiles (3, 3'); and

- a stiffening cross member (R1, R2) mounted astride two first profiles (3) disposed in parallel position; wherein said stiffening cross member (R1, R2) comprises

- two brackets (1) connected to the two profiles (3); and

- a connection profile (2) connected to both brackets (1) and abutting against the second face (P2) of the panel (P);

wherein each bracket (1) comprises:

- a coupling body (10) having a longitudinal axis (Y) suitable for being disposed in parallel direction to the profile (3); and

- a retention foot (14) protruding laterally from the coupling body (10) of the bracket (1) and suitable for being engaged in said undercut (35) defined by the upper tooth (331) of the outer side (33) of the body (3a) of the profile;

wherein the coupling body (10) is configured in such a way to be elastically compressed toward its longitudinal axis (Y) so that the retention tooth (14) can reach a position suitable for passing through the narrowed mouth (30a) along a coupling direction that is orthogonal or incident to the bottom wall (31) of the profile (3) and for being elastically fitted into the undercut (35) defined by the upper tooth (331) of the outer side (33) of the profile.

11. The door (S) according to claim 10, wherein the coupling body (10) of the bracket (1) is hollow, has an inverted U-shape and comprises:

- a first leg (11), from which said retention foot (14) protrudes externally;

- a second leg (12); and

- a curved section (110) that connects said two legs (11, 12).

12. The door (S) according to claim 10 or 11, wherein the coupling body (10) comprises anti-misalignment means configured in such a way to firmly hold the coupling body (10) disposed with the longitudinal axis (Y) parallel to the profile (3).

13. The door (S) according to claim 10 or 11 or 12, wherein each bracket (1) comprises connection means (13) which protrude from the coupling body (10) on the side opposite to the side from where the retention foot (14) protrudes and are suitable for protruding beyond the inner side (32) of the body (3a) of the profile (3); wherein said connection profile (2) has ends (20) coupled with said connection means (13) of the two brackets (1).

14. The structure according to claim 13, when dependent on claim 11, wherein the connection means (13) of each bracket (1) comprise:

- a supporting partition (13a) protruding from the second leg (12) and lying on a plane orthogonal to the longitudinal axis (Y) of the coupling body (10); and

- a connection element (13b) connected to the supporting partition (13a) and suitable for being coupled with the end (20) of the connection profile (2).

Drawing