Fitting for connecting two tubular elements and method for producing same

Abstract

Fitting for connecting two tubular elements (2, 3), having an inner sleeve (4) provided with two outer coupling flanges (14, 15) and a locking nut (16) provided with a hooking flange (19), which in an initial configuration has an inner diameter (D4) greater than the outer diameter (D2, D3) of the coupling flanges (14, 15), in order to allow the locking nut (16) to slide along the inner sleeve (4), the coupling flange (19) has an outer diameter (D2, D3) and has an inner diameter (D5) smaller than the outer diameters (D2, D3) of the two coupling flanges (14, 15) in a final configuration in order to allow the coupling flange (19) to be axially locked between the coupling flanges (14, 15).

Description

[0001] Cross - Reference to Related Applications

[0002] This patent application claims priority to Italian Patent Application No. 102022000020499, filed on October 5, 2022, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present invention relates to a fitting for connecting two tubular elements. Background Art

[0004] In particular, the present invention relates to a fitting for connecting two tubular elements of the type including an inner sleeve having a longitudinal axis and bounded axially by a first end face and a second end face opposite to each other.

[0005] The inner sleeve includes a first part and a second part. The first part extends from the first end face and is designed to receive and hold a first tubular element. The second part extends from the second end face and is generally provided with an external coupling flange.

[0006] Typically, the first part of the inner sleeve is bounded by an outer surface having a conical shape provided with a plurality of annular teeth that extend around the longitudinal axis and are distributed along the longitudinal axis.

[0007] The fitting further includes a locking nut, particularly a hexagonal locking nut, which is designed to receive and hold a second tubular element and is provided with an internal hooking flange.

[0008] The locking nut is assembled around the inner sleeve starting from the first end face and moved forward along the inner sleeve so that the hooking flange substantially contacts the coupling flange and is axially locked on the inner sleeve using a locking ring.

[0009] Known fittings for connecting two tubular elements of the above type have some drawbacks, mainly due to the relatively large number of components required due to the presence of the inner sleeve, the locking nut, and the locking ring. Summary of the Invention

[0010] It is an object of the present invention to provide a fitting for connecting two tubular elements that does not have the above drawbacks and is simple and economical to manufacture.

[0011] According to the present invention, there is provided a fitting for connecting two tubular elements as described in claims 1 to 3.

[0012] The present invention further relates to a method for manufacturing a fitting for connecting two tubular elements.

[0013] According to the present invention, there is provided a method for manufacturing a fitting for connecting two tubular elements as described in claims 4 to 8. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will now be described with reference to the accompanying drawings, which show non-limiting embodiments of the present invention, in which:

[0015] Figure 1 is a schematic side view of a preferred embodiment of the fitting of the present invention, in which the components are in cross-section;

[0016] Figure 2 is a schematic side view of two tubular elements connected together using the fitting in Figure 1 , in which the components are in cross-section; and

[0017] FIG. 3 schematically shows a method for manufacturing the fitting in Figure 1 . DETAILED DESCRIPTION

[0018] Referring to Figure 1 and Figure 2 , reference numeral 1 generally denotes a fitting for connecting two tubular elements 2, 3 together.

[0019] The fitting 1 includes an inner sleeve 4, the inner sleeve 4 having a longitudinal axis 5 and being axially bounded by two end faces 6, 7 substantially perpendicular to the axis 5.

[0020] The sleeve 4 is bounded by an inner surface 8 having a cylindrical shape coaxial with the axis 5 and includes a first portion 9 extending from the face 6 and a second portion 10 extending from the face 7, the first portion 9 being designed to receive and hold the first tubular element 2.

[0021] The face 8 is smooth and without cavities, in particular annular, and ensures that the sleeve 4 has a relatively high resistance.

[0022] The portion 9 is bounded by an outer surface 11 having a conical shape and is provided with a plurality of annular teeth 12 extending around the axis 5 and distributed along the axis 5.

[0023] The portion 10 is bounded by an outer surface 13 coaxial with the axis 5 and is provided with a first coupling flange 14 which projects radially outwards from the face 13 and forms a single piece with the sleeve 4.

[0024] The portion 10 is further provided with a second coupling flange 15 which is formed between the face 7 and the first flange 14, projects radially outwards from the face 13 and forms a single piece with the sleeve 4.

[0025] The fitting 1 includes a locking nut 16 which has a hexagonal shape, is designed to receive and hold the second tubular element 3, and is bounded by a plurality of external locking faces 17, six faces 17 in this case.

[0026] According to some variants not shown, the nut 16 has a plurality of faces 17 other than six, for example from four to eight.

[0027] The faces 17 have a height H1 measured parallel to the longitudinal axis 18 of the nut 16, which height H1 is equal to the height H2 of the nut 16 also measured parallel to the axis 18.

[0028] The nut 16 is provided with an internal hooking flange 19 which projects radially inwards from the inner surface 20 of the nut 16, is formed as a single piece with the nut 16, and is made at one end of the nut 16.

[0029] As shown in Figure 3, the flange 19 has an initial internal diameter D1 (Figure 3a) which is smaller than the external diameter D2 of the flange 14 (Figure 3e) and the external diameter D3 of the flange 15 (Figure 3f).

[0030] The nut 16 is axially locked in the base 21, and the flange 19 is widened by inserting a punch 22 into the nut 16 and the base 21 (Figures 3a, 3b and 3c).

[0031] Regarding the above description, it should be noted that the punch 22 includes a guiding portion 23 and a widening portion 24, the diameter of the guiding portion 23 being close to the internal diameter D1, the widening portion 24 having a frustoconical shape and being designed to engage the flange 19 and widen it to an intermediate internal diameter D4 (Figure 3d) which is larger than the external diameter D3 of the flange 15.

[0032] At this time, the nut 16 is inserted onto the sleeve 4 starting from the face 7 and is moved along the sleeve 4 so as to arrange the flange 19 between the two flanges 14, 15 (Figure 3e).

[0033] Finally, the nut 16 is deformed at least at the flange 19 using a pressing device 25 including at least two pressing elements 26, the pressing elements 26 being evenly distributed around the axis 18 and being movable transversely to the axis 18 to compress the nut 16 and deform the flange 19 to a final internal diameter D5 (Figures 3e and 3f) which is smaller than the external diameters D2, D3 of the flanges 14, 15.

[0034] As a result, the nut 16 is axially locked along the sleeve 4 by the engagement of the flange 19 between the flanges 14, 15, and the fitting 1 has a relatively small number of components.

[0035] According to a variant (not shown), the nut 16 is first manufactured, for example by molding, to have an intermediate inner diameter D4 in an initial configuration and is thus deformed by the pressing device 25 so as to have a final inner diameter D5 in a final configuration.

Claims

1. A fitting for connecting two tubular elements (2, 3), the fitting comprising an inner sleeve (4) having a longitudinal axis (5), the inner sleeve being axially delimited by two end faces (6, 7) and further comprising a first part (9) and a second part (10), the first part (9) extending from the first end face (6) and being designed to receive and hold the first tubular element (2), the second part (10) extending from the second end face (7) and provided with a first external coupling flange (14) made in one piece with the inner sleeve (4); and a locking nut (16), in particular a hexagonal locking nut (16), the locking nut being designed to receive and hold the second tubular element (3) and provided with an internal hooking flange (19); characterized in that: The second part (10) is provided with a second outer coupling flange (15), which is obtained between the first coupling flange (14) and the second end face (7) and is made in one piece with the inner sleeve (4); The locking nut (16) is defined by a plurality of outer locking surfaces (17), the outer locking surfaces having a height (H1) measured parallel to the longitudinal axis (5) of the inner sleeve (4), the height (H1) being equal to the height (H2) of the locking nut (16) also measured parallel to the longitudinal axis (5) of the inner sleeve (4); and The hooking flange (19) has an inner diameter (D4) greater than the outer diameter (D3) of the second coupling flange (15) in the initial configuration, so as to allow the locking nut (16) to slide along the inner sleeve (4) starting from the second end face (7), and has an inner diameter (D5) smaller than the outer diameters (D2, D3) of the two coupling flanges (14, 15) in the final configuration, so as to allow the hooking flange (19) to be axially locked between the coupling flanges (14, 15).

2. The fitting according to claim 1, wherein, The inner sleeve (4) is defined by an inner cylindrical surface (8), which is smooth and has no cavities.

3. The fitting according to claim 1 or 2, wherein, The first part (9) of the inner sleeve (4) is defined by an outer surface (11) having a conical shape, the conical shape being provided with a plurality of annular teeth (12), the annular teeth extending around the longitudinal axis (5) of the inner sleeve (4) and being distributed along the longitudinal axis (5).

4. A method for manufacturing a fitting for connecting two tubular elements (2, 3), the fitting comprising an inner sleeve (4) having a longitudinal axis (5), the inner sleeve being axially delimited by two end faces (6, 7) and further comprising a first part (9) and a second part (10), the first part (9) extending from the first end face (6) and being designed to receive and hold the first tubular element (2), the second part (10) extending from the second end face (7) and provided with a first external coupling flange (14) made in one piece with the inner sleeve (4); and a locking nut (14), in particular a hexagonal locking nut, the locking nut being designed to receive and hold the second tubular element (3) and provided with an internal hooking flange (19); the method being characterized by comprising the following steps: A second outer coupling flange (15) is obtained on the inner sleeve (4), the second outer coupling flange (15) being arranged between the first coupling flange (14) and the second end face (7) and being made in one piece with the inner sleeve (4); The locking nut (16) is manufactured such that the hooking flange (19) has an inner diameter (D4) greater than the outer diameter (D3) of the second coupling flange (15) in the initial configuration; Insert the locking nut (16) along the inner sleeve (4) starting from the second end face (7), so as to place the hooking flange (19) between the two coupling flanges (14, 15); And Deform the locking nut (16) such that the hooking flange (19) has an inner diameter (D5) smaller than the outer diameters (D2, D3) of the two coupling flanges (14, 15) in the final configuration, so as to allow the hooking flange (19) to be axially locked between the coupling flanges (14, 15).

5. The method according to claim 4, wherein, The initial configuration of the locking nut (16) is obtained by molding.

6. The method according to claim 4, wherein, The initial configuration of the locking nut (16) is obtained by widening the hooking flange (19) from a first inner diameter (D1) smaller than the outer diameters (D2, D3) of the two coupling flanges (14, 15) to a second inner diameter (D4) greater than the outer diameter (D3) of the second coupling flange (15).

7. The method according to claim 6, wherein, The hooking flange (19) is widened by inserting a punch (22) into the locking nut (16).

8. The method according to any one of claims 4 to 7, wherein The final configuration of the lock nut (16) is obtained by means of a pressing device (25) mounted on the outside of the lock nut (16) and including at least two pressing elements (26), the pressing elements (26) being able to move transversely to the longitudinal axis (18) of the lock nut (16) so as to deform the hooking flange (19).

9. The method according to any one of claims 4 to 8, wherein The lock nut (16) is defined by a plurality of outer locking surfaces (17), the outer locking surfaces (17) having a height (H1) measured parallel to the longitudinal axis (5) of the inner sleeve (4), the height (H1) being equal to the height (H2) of the lock nut (16) also measured parallel to the longitudinal axis (5) of the inner sleeve (4).

10. The method according to any one of claims 4 to 9, wherein The inner sleeve (4) is defined by an inner cylindrical surface (8), the inner cylindrical surface (8) being smooth and without cavities.

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