| CLAIMS 1. Method of manufacturing a radiator element, in particular a radiator, comprising the phases of: providing at least one radiator tube having a longitudinal tube axis (X) ; - providing an upper radiator header and a lower radiator header, each having a box-shaped body defining a header chamber, in said box-shaped body there being a first aperture able to place said header chamber in fluidic communication with a fluid manifold and made around a transversal axis orthogonal to the longitudinal tube axis, and at least a second aperture able to receive a respective end portion of said. tube; - inserting the end portions of the radiator tube in the respective second apertures of the headers, so that one end rim of said end portions projects from the respective second aperture inside the header chamber; and - performing plastic deformation of said end rims so as to obtain a mechanical blocking of said radiator tube to the headers, said plastic deformation being performed by means of an action of deformation exerted along the transversal axis by a forming tool inserted in the header chamber through the first aperture. 2. Method according to claim 1, wherein: - the forming tool has a tool body suitable for being inserted in the header chamber and at least one forming punch which extends from said tool body; - before the phase of inserting the end portions of the tube in the respective second apertures of the headers, the forming tool is inserted in a respective header chamber in such a way that each forming punch finds itself axially aligned with a respective second aperture; - following said phase of inserting the end portions of the tube, the end rim of said end portion surrounds a respective forming punch at least partially. 3. Method according to claim 2, wherein, to perform the plastic deformation of the rims of the end portions of the tube, the forming tool is first made to advance in the opposite direction to the first aperture so as to deform a first portion of said rim and is then made to move backwards towards said first aperture so as to deform a second portion of said rim opposite the first. 4. Method according to any of the previous claims, wherein, before the phase of inserting the end portions of the tube in the respective second apertures of the headers, a sealing element is fitted on each of said end portions able to co-operate with the box-shaped body of the headers. 5. Method according to claim 4, wherein the phase of providing the at least one radiator tube comprises a phase of making an annular step between each end portion and the body of the tube, each sealing element being positioned on a respective annular step. 6. Method according to claim 5, wherein the phase of providing the radiator headers comprises a phase of making, in each secondary aperture, an annular undercut substantially complementary to the annular step made in the radiator tube,' in such a way that, following the mechanical blocking of the tube to the headers, each sealing element is compressed between said step and said undercut . 7. Method according to any of the previous claims, wherein several radiator tubes can be mounted parallel to each other to the upper and lower headers of the radiator, and wherein the forming tool is fitted with at least two forming punches so as to contemporarily perform the plastic deformation of the end rims of at least two tubes. 8. Method according to any of the previous claims, wherein each header is made in a single piece by moulding or die-casting. 9. Radiant element of a radiator comprising: - at least one radiator tube having ' a longitudinal tube axis (X) ; - an upper radiator header and a lower radiator header, each having a box-shaped body defining a header chamber, in said box-shaped body there being a first aperture able to place said header chamber in fluidic communication with a fluid manifold and made around a transversal axis orthogonal to the longitudinal tube axis, and at least a second aperture wherein a respective end portion of said tube is inserted, where the at least one radiator tube is blocked to the headers by plastic deformation of one end rim of its two end portions, characterised by the fact that the box-shaped body of each header is made in a single piece. 10. Radiant element of a radiator according to claim 9, wherein the. first aperture of the headers faces in a direction perpendicular to the direction along which a row of radiator elements extend in a radiator. 11. Radiant element of a radiator according to claim 9 or 10, wherein each radiator header has a closed wall axially opposite to the wall which the first aperture is made on . 12. Radiant element of a radiator according to any of the claims 9-1-1, wherein on each end portion of each tube a sealing gasket is fitted which co-operates with a portion of the box-shaped body which defines a respective second aperture. 13. Radiant element of a radiator according to claim 12, wherein between each end portion and the tube body there is an annular step, and wherein in each second aperture there is an annular undercut substantially complementary to said annular step, in such a way that, following mechanical blocking of the tube to the headers, each sealing element is compressed between said step and said undercut. 14. Radiant element of a radiator according to any of the claims 9-13, comprising a beam of tubes formed of at least two radiator tubes parallel to each other which extend between the two upper and lower headers, wherein the box-shaped body of each header and the relative header chamber extend mainly along a header axis perpendicular to the tube axis, in the plane formed by said beam f tubes, and wherein the first aperture is made at one end of said box-shaped body. 15. Radiant element of a radiator according to claim 14, wherein each header is a substantially tubular shape, where the header chamber is substantially cylindrical and where the first aperture has the same through section as the transversal section of said chamber. 16. Radiant element of a radiator according to claim 15, wherein each second aperture is made in an emergent connection portion of the box-shaped body which extends orthogonal to the extension axis of the header. 17. Radiator comprising a plurality of radiant elements according to any of the claims 9-16 flanking each other along a horizontal radiator axis (Z) , an upper fluid manifold in fluidic communication with the upper headers and a lower fluid manifold in fluidic communication with the lower headers. 18. Radiator according to claim 17, wherein each header extends between two opposite ends along a header axis perpendicular to the tubes of the radiator and to the horizontal radiator axis, and wherein each manifold is attached to one end of said headers. 19. Radiator according to claim 18, wherein each manifold comprises a tubular body which extends parallel to the horizontal radiator axis and which has, on the side facing the headers, a substantially flat wall coupling to the box-shaped body of the headers, along said flat wall there being a plurality of holes, each of which able to place the header chamber in fluidic communication with the inside of the manifold. 20. Radiator according to claim 19, wherein, on each header, in said flat wall there is a hole for the passage of an attachment screw of the manifold to the box-shaped body. |
"Method for manufacturing a radiator element, radiator element and radiator"
[0001] . The present invention relates to a method for manufacturing a radiant element of a radiator, heated towel rack or similar heating system based on the circulation of a hot fluid, such as water. The present invention also relates to the radiant element and radiator obtained using such method.
[0002] . Merely for the purposes of explaining the present invention, the description below will be made with reference to the radiator of a hot water heating system.
[0003] . As known, the radiant elements of a hydraulic system are often composed of two parallel tubular manifolds, for example upper and lower, connected fluidically by a plurality of tubes positioned transversally to said manifolds. The two manifolds themselves are often composed of modular elements, connectable to each other known as "headers" of the radiant element. The headers of the end elements of the radiator are connected to the heating system. The production of radiant elements of different sizes according to need is thus made possible, with which, for example, rooms can be heated via the circulation of hot water.
[0004] . In one embodiment, to manufacture this type of known radiator, lateral holes are made on each element of the two manifolds to connect them to the adjacent elements and further holes are made, calibrated to the diameter of the tubes connecting the upper and lower manifolds. Once the elements of the manifolds have been prepared and the sections of tube have been cut to the desired length, they are connected by welding. This type of connection has the advantage of being water-tight and resistant to the stress caused by the supply pressure of the system which can reach considerable intensity.
[0005] . However the connection by welding of the components of the radiator entails a series of difficulties during manufacturing. First of all, calibration of the holes on the manifolds depending on the diameter of the connection tubes, cutting of the sections of such connection tubes and preparation of the surfaces to apply the welding bead to, are all operations which must be extremely precise to ensure a good weld. Added to this is the fact that despite careful preparation, the quality of the weld is not always satisfactory from a structural, functional and/or aesthetic point of view.
[0006] . In another embodiment, described for example in WO2005/014199, each tube is first subjected to a first plastic deformation of its connection ends to the headers, so as to obtain a shoulder on each of said ends. The manifold elements, or headers, are composed of' a box- shaped body open on one side wherein a lateral hole is made on each of two side walls of said box-shaped body, adjacent to the open side and opposite each other, at least one hole is made on the wall opposite the open side, able to receive one end of a respective tube, said hole having a stop complementary to the shoulder of said tube end.
[0007] . The manufacturing method entails inserting the ends of the tubes in the respective holes of the manifold elements; said ends are then subjected to a second plastic deformation so as to obtain mechanical blocking of the tubes to the manifold elements 3. Lastly, the box- shaped bodies of said manifold elements are attached to the body by special covers, preferably by screwing.
[0008] . The manufacturing method described above allows to obviate some of the drawbacks complained of in relation to fully welded radiators. In fact, by not using welding phases, the strict need to check the tolerance of the couplings · no longer exists. In particular, the key coupling between the connection tubes and manifold elements, thanks to blocking by plastic deformation of the ends of the tubes, does not require strict control of the tolerances. This way, the manifold element, which is preferably manufactured by die-casting, does not require further machine processing.
[0009] . It has been seen however that against the advantages mentioned above, the fact of making the manifold elements in two pieces, the box-shaped body and relative closure cover, which must be attached to each other at the end of the manufacturing process for example by screwing and with the interposition of a sealing gasket, considerably influences the production costs of the radiator and in any case constitutes a possible cause of leakage of the heating fluid.
[0010] . The purpose of the present invention is to excogitate and render operative a manufacturing method of a radiant element for radiators which makes it possible to overcome the drawbacks mentioned with reference to the prior art. The aim at the basis of the invention is also to manufacture a radiator with structural and functional characteristics such as to satisfy the aforesaid requirements . [0011]. Such · problems are resolved by a manufacturing method of a radiant element according to claim 1, by a radiant element of a radiator according to claim 9 and by a radiator according to claim 17.
[0012] . Further characteristics and advantages of the method and of the device according to the invention will be clear from the description below made by way of a non- limiting example of some preferred embodiments, with reference to the attached drawings, wherein:
[0013] . Figure 1 is an exploded view, in longitudinal section, of the upper part of a radiant element of a radiator (the lower part is identical) ;
[0014] . Figure 2 is a longitudinal section of the radiant element assembled;
[0015] . Figure 3 shows, in longitudinal section, a tube and two headers of the radiant element, before assembly;
[0016] . Figure 4 shows, in longitudinal section, the upper portions of the tubes of a radiant element after assembly to a header;
[0017] . Figure 5 is a section of the header in Figure 4 along the section line A-A;
[0018] . Figure 6 is a longitudinal section of the radiant element in Figure 4 along the section line B-B;
[0019] . Figures 7-10 show, in longitudinal section, the same number of. assembly phases of a radiant element;
[0020] . Figure 11 shows a radiator according to the invention, from a side view; and
[0021]. Figure 12 shows the radiator seen from above.
[0022] . With reference to the attached drawings, the radiant element of a radiator according to the present invention, globally denoted by reference numeral 1, comprises at least one radiator tube 10 having a longitudinal tube axis X; preferably, the radiant element 1 comprises a plurality of tubes 10, lying parallel to each other, for example three tubes 10, as shown in the drawings. Each tube 10 has two end portions 11.
[0023] . The radiant element 1 comprises, in addition, an upper radiator header 20 and a lower radiator header 20'. Said headers are. the same as each other and couple to the tubes 10 in the same way. As will be explained further below, the upper header 20 connects to an upper fluid manifold 40; the lower header 20' connects to a lower fluid manifold 40' . Further on in the description reference will be made to the upper part of the radiant element and of the radiator, the lower part being the same and symmetrical in relation to a median axis.
[0024]. Each header 20, 20' has a box-shaped body 22 defining a header chamber 24. In said box-shaped body 22 a first aperture 26 is made, able to place said header chamber 24 in fluidic communication with the fluid manifold 40, 40' , and at least a second aperture 28 in which a respective end portion 11 of a radiator tube 10 is inserted. The first aperture 26 is made around a transversal axis Y orthogonal to the longitudinal tube axis X.
[0025] . Advantageously, the box-shaped body 22 of each header is made in one piece. In other words, said box- shaped body 22 has no screwed or soldered parts but is made directly in one piece by moulding or die-casting, depending on the material used.
[0026] . According to one form of embodiment, the first aperture 26 of the headers faces perpendicular to the direction along which a row of radiant elements extend in a radiator, indicated by the radiator axis Z in Figure 12.
[0027] . In particular, each radiator header 20, 20' has a closed wall 29 axially opposite the wall which the first aperture 26 is made in.
[0028] . In each of the second apertures 28 there is an annular undercut 30. In one embodiment, moreover, each second aperture 28 is made in an emergent connection portion 31 to the .tubes 10. [0029] . According to a preferred embodiment, on each end portion 11 of each tube 10 a sealing gasket 12 is fitted, which co-operates with a portion of the box- shaped body 22 defining a respective second aperture 28. In particular, between each end portion 11 and the body of the tube 10 there is an annular step 13, the sealing gasket 12 being positioned on said annular step 13. Advantageously, the annular undercut 30 of the second aperture 28 and the annular step 13 are substantially complementary to each other, that, is they form a shaped coupling. Following the insertion of the tubes in the headers, and their blocking, each sealing element 12 is compressed between said step 13 and said undercut 30.
[0030] . As mentioned above, in a preferred embodiment the radiator element 1 comprises a beam of tubes formed of at least two radiator tubes 10 parallel to each other which extend between the two upper and lower headers 20, 20' . In this case, the box-shaped body 22 of each header and the relative header chamber 24 extend mainly along a header axis Y perpendicular to the tubes axis X, in the plane formed by said beam of tubes. In this case, the first aperture 26 is made at one end of said box-shaped body 22.
[0031] . In a preferred embodiment, each header 20, 20' is a substantially tubular shape, with the header chamber 24 substantially cylindrical. In this case, the first aperture 26 has . the same through section as the transversal section of said cylindrical chamber 24. The emergent connection portions 31 to the tubes 10 extend perpendicularly from the tubular body which defines the cylindrical chamber 24, perpendicularly to the extension axis Y of the header 20.
[0032] . A radiator 50 according to the present invention comprises a plurality of radiator elements 1 flanking each other along a horizontal radiator axis Z, an upper fluid manifold 40 in fluidic communication with the upper headers 20 and a lower fluid manifold 40' in fluidic communication with the lower headers 20' . In particular, preferably, each header 20, 20' extends between two opposite ends along a header axis Y perpendicular to the radiator tubes 10 and to the horizontal radiator axis Z, and each manifold 40, 40' is attached to one end of said headers. Consequently, unlike the known radiators, the manifolds do not extend centrally in relation to the beam of tubes of each radiant element, but on one side of said beam, preferably the side nearer the wall to which the radiator is attached. [0033] . Advantageously, each manifold 40, 40' comprises a tubular body ,42 which extends parallel to the horizontal radiator axis Z and which has, on the side facing the headers 20, 20', a substantially flat wall 44 coupling to the box-shaped body 22 of the headers. Along said flat wall 44 are a plurality of passages 46, each able to place the chamber 24 of a header in fluidic communication with the inside of the manifold 40, 40' .
[0034] . Advantageously, on each header, in said flat wall 44 there is also a hole 48 for the passage of an attachment screw 49 of the manifold 40, 40' to the box- shaped body 22 of the headers.
[0035] . The method of embodiment of the radiant element and of the radiator illustrated above will now be described.
[0036] . After making the tubes 10 and the headers 20, 20' , and having preferably mounted the sealing gaskets 12 on said tubes, the end portions 11 of the radiator tubes 10 are inserted in the respective second apertures 28 of the headers 20, 20', so that one end rim 11' of said end portions 11 projects from the respective second aperture 28 inside the header chamber 24.
[0037 ] . Subsequently, a plastic deformation of said end rims 11' is performed so as to obtain a mechanical blocking of the radiator tubes 10 to the headers 20, 20' . Said plastic deformation is performed by means of a deformation exerted along the transversal axis Y, orthogonal to the tubes axis X, by a forming tool 100 inserted in the header chamber 24 through the first aperture 26.
[0038] . Said forming tool 100 has a tool body 102 suitable for insertion inside the header chamber 24 and at least one forming punch 104 which extends from said tool body 102.
[0039] . In one preferred embodiment, before inserting the end portions 11 of the tube 10 in the respective second apertures 28 of the headers, the forming tool 100 is inserted in a respective header chamber 24 in such a way that each forming punch 104 finds itself axially aligned, along the tubes axis X, with a respective second aperture 28.
[0040] . When the end portions 11 of the tubes 10 are inserted in the headers, the end rim · 11' of said end portion 11 surrounds a respective forming punch 104 at least partially.
[0041] . Starting from this condition, to perform plastic deformation of the rims 11' of the end portions advance in the opposite direction to the first aperture 26 (in the direction of the arrow Fl in Figure 9) , so as to deform a first portion 11' a of said rim 11', and is then made to move backwards towards said first aperture 26 (in the direction of the arrow F2 in Figure 10) so as to deform a second portion ll'b of said rim 11' opposite the first. For example, the portions 11' a and ll'b of the rim 11' are semi-cylindrical portions.
[0042] . Following the translation of the tool, the rim 11' of the end portion 11 is then bent and flattened on the end 24' of the header chamber 24, to achieve mechanical' blocking of the tubes to the headers. In one preferred embodiment, each forming punch 104 has a working surface 104' of a complementary shape to the surface of the end of the header chamber. For example, in the case of the header chamber 24 of a cylindrical shape, each forming punch 104 has a semi-spherical working surface 104' .
[0043] . It should be noted that, advantageously, the forming tool 100 is configured in such a way that, when it is inserted in the header chamber 24, the tool body 102 and forming punches 104 slide respectively at least on the upper wall 23 of the box-shaped body 22, opposite the second apertures 28, and on the end 24' of the header chamber 24. This way the forming tool 100 is correctly guided in its translation inside the header chamber 24 and the rim 11' of the end portions 11 of the tubes 10 is bent and flattened so as to adhere perfectly to the end wall of the header chamber, acquiring its shape.
[0044] . In the preferred case wherein several tubes 10 can be assembled parallel to each other to the upper and lower headers of the radiator, the forming tool 100 is fitted with at least two forming punches 104 so as to contemporaneously perform the plastic deformation of the end rims 11' of at least two tubes 10.
[0045] . It should be noted that, again in the case of a number of two or more tubes, in order to limit transversal encumbrance, that is along the extension axis Y of the headers of the radiant elements 1, the rim 11' of the outermost tube, that is the furthest from the first aperture 26, can be left unbent. For example, to enable the free sliding of the forming tool 100 inside the header chamber 24, the end portion 11 of the outermost tube may be shorter than the other. tubes, so as to be aligned, when said outer tube is inserted in the header, with the end wall 24' of the header chamber 24.
[0046] . This way, said tube proves substantially aligned with the closed end wall 29 of the headers. In fact, it has been seen that once the mechanical blocking of the headers to the tubes by means of the plastic deformation of the end rims 11' of at least one tube 10 has been performed, tightness against the leakage of heating fluid from the second apertures 28 of the headers is guaranteed by the presence of the sealing gasket 12 mounted on the end portions 11 of the tubes 10.
[0047] . Lastly, as regards the assembly of the radiator, as described above it is sufficient to connect the headers of the radiant elements to the lateral upper 40 and lower manifolds 40' for example by means of screws 29.
[0048] . From the above description it is evident how thanks to the method of embodiment of the radiant element according to the invention all the advantages of weld- free radiators have been achieved while at the same time overcoming the technical and economic drawbacks related to the need to close the box-shaped body of the headers with a special cover.
[0049] . Moreover, the fact of having the manifolds lateral rather than central considerably facilitates cleaning of the radiator, in that the space between the radiant elements is free and therefore fully accessible, also making the radiator structure lighter from an aesthetic point of view.