EP3141311A1

EP3141311A1 - Enhanced slide for a bending machine for elongated tubular elements

Info

Publication number: EP3141311A1
Application number: EP16186950.8A
Authority: EP
Inventors: Giorgio Vezzani
Original assignee: Cbc Srl
Current assignee: Cbc Srl
Priority date: 2015-09-03
Filing date: 2016-09-02
Publication date: 2017-03-15
Anticipated expiration: 2036-09-02
Also published as: ITUB20153370A1; EP3141311B1

Abstract

An enhanced slide (24) for a bending machine (10) for tubular elements (15) slidable by way of guides (22) on a support structure (12) with respect to which there is arranged a roller-shaped bending matrix (14) provided with a groove (16) featuring a circumferential development, said slide (24) comprising a support structure (32) for a counter matrix (26) and provided with movable means suitable for increasing the pressure of the deformation exerted by said counter matrix (26) onto the tubular element (15) located between the bending matrix (14) and the counter matrix (26).

Description

The present invention refers to an enhanced slide for a bending machine for elongated tubular elements.
More specifically, the present invention refers to a slide for a bending/curving machine for tubular elements suitable for bending said tubular elements both rightwards and leftwards.
It is known that the purpose of tube bending or curving is to realize well terminated forms and/or paths for a tube (for instance in the case of tubes for heat exchangers or the like) or also to impart a greater stiffness to a tubular structure.
The tubular element bending or curving process can be implemented by using manually operated devices as well as apparatuses of automatic or semi-automatic types.
Considering said automatic apparatuses more specifically, some technical solutions rather complex from the mechanical point of view implement the bending operation by using bending assemblies or heads mounted on guides or trolleys that are movable transversally to the direction of the longitudinal development of the tube and are provided with driving gears suitable for moving said assemblies equipped with shaped bending formers in the direction to and in contact with the tubular element to be deformed.
Other solutions implement the tubular element bending in a simpler manner by way of a head equipped with a fixed bending matrix and a movable bending arm rotatable about said fixed bending matrix.
Further known solutions implement the bending operation by using a bending matrix provided with a groove whose shape or configuration is selected as a function of the characteristics of the tube to be processed and a counter matrix suitable for coupling with the bending matrix and movable on a slide or trolley.
However, such known solutions feature some important drawbacks related to their structural complexity and to the need for introducing machine downtimes in order to perform bending operations according to different directions.
A further drawback consists in that such solutions, in particular in the case of thin tubular elements, do not allow to curb the deformations in the tubular element during the bending operation bound to the pressure exerted onto the tubular element enclosed between the bending matrix and the counter matrix.
A further drawback consists in that in traditional bending machines the tubular element is subject to oscillations in the terminal section not comprised between the bending matrix and the counter matrix which might result in undesired deformations in the tubular element itself.
An object of the present invention is to obviate the above mentioned drawbacks.
More specifically, an object of the present invention is to provide a bending machine for elongated tubular elements equipped with an enhanced slide suitable for allowing to curb the deformations in the tubular element during its deformation.
A further object of the present invention is to provide a tube bending machine suitable for preventing oscillations from occurring in the terminal section of the tubular element during the bending step.
A further object of the present invention is to provide a tube bending machine suitable for regulating and increasing the pressure force onto the tube during the bending step as a function of the characteristics of the tube to be bent.
A further object of the present invention is to put at users' disposal a bending machine for elongated tubular elements equipped with an enhanced slide suitable for guaranteeing high strength and reliability values over time and also such as to be easily and economically realized.
These objects and others are achieved by the invention that presents the characteristics according to claim 1.
According to the invention an enhanced slide is provided for a tubular element bending machine slidable by way of guides on a support structure with respect to which a roller-shaped bending matrix provided with a groove featuring a circumferential development is rotatably arranged, said slide comprising a support structure for a counter matrix and being equipped with movable means suitable for increasing the deformation pressure exerted by said counter matrix onto the tubular element located between the bending matrix and the counter matrix.
Advantageous embodiments of the invention are apparent from the dependent claims.
The mechanical and functional characteristics of the enhanced slide for a bending machine for elongated tubular elements according to the present invention can be better understood from the following detailed description, wherein reference is made to the attached drawing tables which represent a preferred but not limitative embodiment thereof and wherein:

figure 1 schematically shows a side view of a bending machine for elongated tubular elements provided with an enhanced slide according to the invention;
figure 2 schematically shows a top view of the bending machine equipped with the enhanced slide according to the invention;
figure 3 schematically shows an enlarged side view of a portion of the bending machine in correspondence with the enhanced slide according to the invention in a first operating position;
figure 4 schematically shows a cross-sectional view according to a plane A-A as per figure 3;
figure 5 schematically shows an enlarged side view of a portion of the bending machine in correspondence with the enhanced slide according to the invention in a second operating position;
figure 6 schematically shows an enlarged side view of a portion of the bending machine in correspondence with the enhanced slide according to the invention, said slide being in accordance with an alternative embodiment;
figure 7 schematically shows a side view of the bending machine for elongated tubular elements equipped with an enhanced slide according to a further alternative embodiment;
figures 8 thru 10 schematically show a top view of the bending machine equipped with the enhanced slide of the invention according to the further alternative embodiment of figure 7 during the tubular element bending steps.

With reference to the mentioned figures, the bending machine for elongated tubular elements equipped with the enhanced slide according to the invention, identified by the numeral reference 10 as a whole in figures 1 and 2, comprises a support structure 12 on which there is firmly located a roller-shaped bending matrix 14 provided with a groove 16 featuring a circumferential development and whose dimensions and shape are functions of the characteristics of the tubular elements 15 to be submitted to a bending process.
The groove 16 is broken at the ends in correspondence with one of which there is provided a retention means 18 for the tubular element to be bent consisting of a U-shaped element whose free ends are secured to the bending matrix 14 by way of a pivot 17 or an equivalent retention means.
The bending matrix 14 is driven into rotation by a shaft 20 driven by an electric motor (not represented in the figures).
On the support structure 12 there is also slidingly arranged, along guides 22, a slide 24 supporting a counter matrix 26 provided with a hollow 27 whose dimensions and shape are selected as a function of the dimensional characteristics of the tubular element 15 to be bent and, in any case, corresponding to those of the hollow 16 of the bending matrix 14.
The slide 24 is driven into movement along the guides 22 of the support structure 12 by way of a manually operated handwheel 28 which operates a coupling of the screw-nut screw type and a lever 30 the function of which is to lock the slide 24 with respect to the support structure 12 whenever the grooves 16 and 27 of the bending matrix 14 and of the counter matrix 26 respectively are in contact with the outer lateral surface of the tubular element 15.
The counter matrix 26 is mounted on a trolley 31 movable with respect to a support structure 32 of the counter matrix 26.
In the preferred embodiment according to figures 2 thru 4, the counter matrix 26 is organized into sectors and, more specifically, it comprises two or more counter matrix sectors 40 interchangeable with each other and secured to the trolley 31 by way of a dovetail coupling or a T-shaped slot or a similarly known one.
In the case of tubular elements featuring small diameters, the counter matrix sectors 40 of the counter matrix 26 might be replaced by one counter matrix element 42 also secured to the trolley 31 by way of a dovetail or similar coupling (as schematically shown in figure 6).
The plane of the trolley 31 on which the counter matrix 26 (either in the multi-sector configuration 40 or in the simple configuration 42 as described above) is firmly placed defines an inclined plane whose slope increases by moving in the direction of the free end of the tubular element not engaging the retention means 18.
The trolley 31 is slidable with respect to the support structure 32 of the slide 24 by way of two rollers 44 and 44' transversally and rotatably arranged with respect to said support structure 32 of the slide 24; the function of such rollers is to reduce the friction between the trolley 31 and the support structure 32 while the tubular element 15 is being bent, as better detailed below.
Pivots 46 are arranged transversally to the support structure 32 internally and coaxially to said two rollers 44 and 44' and perform the function of guaranteeing a coupling between said trolley and said support structure. The trolley 31 is also provided with a regulation means consisting of a screw 48 whose function is to regulate the stroke (identified by the letter "C" in figure 3) of said trolley 31 with respect to the support structure 32; said regulation means is preferably arranged in correspondence with an end of the trolley 31 opposite to that in correspondence with which the free end of the tubular element 15 engages the retention means 18 and according to a direction parallel to that according to which the same trolley moves.
The regulation of the stroke C (determined by the distance between the tip of the regulation screw 48 and the roller 44) of the trolley 31 takes place in the range from a maximum stroke value to a minimum stroke value or stroke zero (wherein the tip of the regulation screw 48 is in contact with the roller 44).
Said stroke regulation of the trolley 31 with respect to the support structure 32, together with the inclined plane defined by the structure of the trolley itself, makes it possible to regulate and, more specifically, to increase the pressure of the deformation exerted by the counter matrix 26 onto the tubular element 15 to be bent.
As a matter of fact, during the bending deformation of the tubular element 15, the trolley 31 slides with respect to the support structure up to getting in contact with a stop defined by the stroke regulation screw 48, as schematically shown in figure 3 (maximum stroke) and in figure 5 (end of stroke); such sliding of the trolley 31 with respect to the support structure 32, together with the inclined profile of the trolley itself which increases the deformation pressure onto the tubular element 15 and with the reduced friction due to the presence of the rollers 44 and 44' makes it possible a bending process featuring a greater and optimum curb of the deformations induced onto the tubular element itself.
In the case of tubular elements featuring small diameters, the counter matrix 26 comprising counter matrix sectors 40, might be replaced, as described before, by one counter matrix element 42 only, the deformation mode of the tubular element remaining the same.
Figures 7 thru 10 show a further alternative embodiment of the enhanced slide applied to the bending machine for elongated tubular elements.
For said further alternative embodiment, identified by the reference numeral 50 as a whole in figures 7 thru 10, the elements common to the embodiment of figures 1 thru 6 will be identified by the same reference numerals and will not be the object of any further and detailed description.
The mentioned slide 50 is, as in the case of the slide 24 according to the preferred embodiment, applied to the machine 10 for bending elongated tubular elements 15 which comprises the support structure 12 onto which there is firmly placed the roller-like bending matrix 14 provided with a groove 16 featuring a circumferential development with dimensions and shape corresponding to those of the tubular element 15 to be submitted to a bending process.
Onto the support structure 12 there is slidingly arranged a slide 50 which supports a counter matrix 26' provided with a hollow or groove 27' whose dimensions and shape are selected as a function of the dimensional characteristics of the tubular element 15 to be bent.
The slide 50 is driven into movement along the guides 22 of the support structure 12 by way of a handwheel 28 which operates a coupling of the screw-nut screw type and of the lever 30 the function of which is to lock the slide 50 with respect to the support structure 12 whenever the grooves 16 and 27' of the bending matrix 14 and of the counter matrix 26' respectively are in contact with the outer lateral surface of the tubular element 15.
The counter matrix 26' is mounted on a trolley 31' which is movable with respect to a support structure 32' of the counter matrix 26'.
The front of the trolley 31' on which the counter matrix 26' is firmly mounted is arranged on a horizontal plane and does not define an inclined plane as described with reference to the embodiment of figures 1 thru 6.
The counter matrix 26' comprises a counter matrix element 54 secured to the trolley 31' by a coupling of the dovetail type or an equivalent known type suitable for this purpose, said counter matrix element 54 consisting of one body and its groove 27' featuring a shape tangent to a radius of the tubular element 15, or the groove 27' itself of the counter matrix element 54 featuring a rectilinear shape; the shape itself of said counter matrix element 54 can feature a constant development or a conical development, this in order to improve the bending of thin tubes or standard thickness tubes featuring very narrow bending radii.
The trolley 31' is slidable with respect to the support structure 32' of the slide 50 by way of a roller 56 transversally and rotatably arranged with respect to said support structure 32' of the slide 50; in this embodiment too, the function of the roller is to reduce the friction between the trolley 31' and the support structure 32' while the tubular element 15 is being bent.
A pivot 46' is arranged transversally to the support structure 32' internally and coaxially to the roller 56 in order to guarantee the coupling between the trolley 31' and the support structure 32'.
Said roller 56 is slidable in a through passing slotted opening 58 formed on opposite side shoulders 33 of the support structure 32' with respect to which the trolley 31' slides; said slotted hollow 58 features a longitudinal development with an inclination that grows in the direction of the retention means 18 of the tubular element 15.
The trolley 31' is also provided with a regulation means consisting of a screw 60 suitable for regulating the stroke (identified by the letter "C" in figure 9) of said trolley 31' with respect to the support structure 32'; such regulation means is preferably arranged in correspondence with the end of the trolley 31' opposite to that in correspondence with which the tubular element 15 engages the retention means 18 and is positioned according to a direction parallel to the sliding direction of the trolley 31'.
The screw 60 accommodates a pivot 62 slidable internally and coaxially to said screw and an elastic element consisting of a helical spring 64 operating as an elastic return for the mentioned pivot 62.
As already described above, the regulation of the stroke C takes place in the range from a minimum stroke value or stroke zero to a maximum stroke value, the pivot 62 being permanently in contact with the roller 56; in this way, the deformation pressure exerted by the counter matrix 26' onto the tubular element 15 is regulated.
During the deformation step, the trolley 31' slides with respect to the support structure 32' as a function of the stroke "C" determined by means of the regulation screw 60 (as indicated by the arrow Y in figure 9) and the mechanical characteristics of the counter matrix element 54 make it possible to exert a very low force onto the tubular element 15 during the initial bending deformation step, which, increases (in terms of pressure) proportionally to the displacement while the tube is sliding with respect to the groove of said counter matrix element, thus deforming the tubular element minimally during the initial step so as to strongly limit the presence of stresses internal to said tube during the initial step.
Considering the movement of the roller 56 along the inclined slotted opening 58 of the support structure 32', the trolley 31', during its own sliding movement with respect to the support structure 32' driven by the tubular element 15, oscillates and follows the tubular element during the bending step, in this way guaranteeing an optimum bending of the tube, with no undesired stresses and strains in said tubular element.
In addition, in the slide according to the above described further alternative embodiment, when the machine goes back (as indicated by the arrow B' in figure 10) the trolley 31' also goes back to its initial position (also thanks to the presence of the helical spring 64) thus discharging the pressure onto the tubular element and making it possible to release said tubular element without any forcing (which might induce undesired stresses, deformations, and strains).
The above considerations make the advantages achieved by the enhanced slide according to the invention apparent.
The enhanced slide according to the invention applied to a bending machine for elongated tubular elements advantageously makes it possible to perform bending operations on tubes while curbing and reducing the residual deformations present in the tubular element during the deformation step; this is achieved thanks to the increased pressure induced onto the tubular element thanks to the movable trolley supporting the counter matrix and provided with an inclined plane, combined with the possibility of regulating the stroke of said movable trolley and with the reduced friction generated in the sliding movement of the movable trolley itself.
A further advantage of the enhanced slide according to the invention consists in that the counter matrix configuration comprises counter matrix sectors interchangeable with each other as a function of the dimensions of the tube to be bent and whose positions are interchangeable; this allows to increase the service life of the counter matrix.
A further advantage consists in that the enhanced slide according to the invention makes it possible to perform bending operations on a tubular element without causing oscillations to occur in the tubular element itself in correspondence with its terminal part not engaged between the bending matrix and the counter matrix (as indicated by the arrows X in figure 2 and in figure 8) which results in advantages qualitatively wise.
Even though the invention has been described here above with a special reference to an embodiment thereof which is provided for explanatory non limitative purposes only, numerous modifications and variants will be apparent to those skilled in this matter in the light of the above description. Therefore, the present invention is to be construed to embrace all modifications and variants that fall in the scope of the following claims.

Claims

An enhanced slide (24, 50) for a bending machine (10) for tubular elements (15) slidable by way of guides (22) on a support structure (12) with respect to which there is rotatably arranged a roller-shaped bending matrix (14) provided with a groove (16) featuring a circumferential development, said slide (24, 50) being characterized in that it comprises a support structure (32, 32') for a counter matrix (26, 26') and also comprising a trolley (31, 31') with respect to which the counter matrix (26, 26') is firmly secured, said trolley being movable with respect to the support structure (32, 32') and according to a longitudinal direction of development of the tubular element (15) to increase the deformation pressure exerted by said counter matrix (26, 26') onto the tubular element (15) located between the bending matrix (14) and the counter matrix (26).
A slide according to claim 1, characterized in that the plane of the trolley (31) with respect to which the counter matrix (26) is firmly secured defines an inclined plane.
A slide according to claim 1 or 2, characterized in that the trolley (31) is slidable with respect to the support structure (32) by way of rollers (44, 44') transversally and rotatably arranged with respect to said support structure (32).
A slide according to any of the previous claims, characterized in that the trolley (31) is provided with a regulation means consisting of a screw (48) suitable for regulating the stroke of said trolley (31) with respect to the support structure (32).
A slide according to any of the previous claims, characterized in that the trolley (31) comprises two pivots (46) arranged transversally to the support structure (32), internally and coaxially to the rollers (44, 44'), performing the function of guaranteeing the coupling between said trolley and said support structure.
An enhanced slide according to any of the previous claims, characterized in that the counter matrix (26) comprises two or several interchangeable counter matrix sectors (40) secured to the trolley (31).
A slide according to any of the previous claims, characterized in that the counter matrix (26) consists of one counter matrix element (42) secured to the trolley (31).
A slide (50) according to claim 1, characterized in that the counter matrix (26') comprises a counter matrix element (54) consisting of one longitudinally developed hollow or groove (27') mounted onto a trolley (31'), the upper front of which with respect to which the counter matrix (26') is firmly secured being arranged according to a horizontal plane and said trolley (31') being slidable with respect to the support structure (32') by way of a roller (56) transversally and rotatably arranged with respect to said support structure (32'), supported by a pivot (46') and slidable in a slotted opening (58) located on opposite side shoulders (33) of the support structure (32'), said slotted hollow (58) featuring an inclined longitudinal development.
A slide (50) according to claim 8, characterized in that the trolley (31') is provided with a regulation means consisting of a screw (60) suitable for regulating the stroke of said trolley (31') with respect to the support structure (32'), said screw (60) accommodating a pivot (62) slidable internally and coaxially to said screw (60) and an elastic element consisting of a helical spring (64) the function of which is to constitute an elastic return for said pivot (62) and for said trolley (31').
A slide (50) according to claim 9, characterized in that the hollow or groove (27') features a shape tangent to a radius of the tubular element (15).
A slide (50) according to claim 10, characterized in that the hollow or groove (27') features a rectilinear shape.
A slide (50) according to any of claims 10 thru 11, characterized in that the hollow or groove (27') features a constant development in the longitudinal direction.
A slide (50) according to any of claims 10 thru 12, characterized in that the hollow or groove (27') features a conical development in the longitudinal direction.