FR2774624A1 - Shaping fold lines in a profile body for a double glazing frame - Google Patents

Abstract

To fold a hollow profile (1), of an extruded thermoplastic material with a cladding foil (2) of aluminum on one surface and a temp. gradient from one wall of the hollow profile to the other wall (11,12), a hot shaping tool (4) is pressed against the uncoated wall (12) surface and force it against the facing wall (11). The wall compression forms a folding line across the wall (11,12) surfaces, at right angles to the cladding foil (2). The profiled body (1) is heated to its softening point. The side walls of the profile are supported while the hot shaping tool (4) is applied, and then they are shaped to conform to the folding line. The position of the folding line is determined where the profiled body has to be manipulated, where one wall surface is covered by the cladding foil (2), and within the foil area, or outside the foil area. After the folding line has been shaped, the profile body material is cooled at least at the folding line. A number of folding lines are imposed on the profile body, with simultaneous operations of heating a body section while the tool holder (3) presses the tool (4) into a folding line, to prepare the section for the next folding line. Each folding line is cooled after it has been shaped. A single shaping station is used, with the profile moved progressively through it. A cladding foil can be applied to a wall area in sequence, before the fold line is imposed. After the fold line has been formed, the side walls are folded inwards. A heated body can be inserted into the fold line, to form a pivotal part of the finished fold. The body is pushed into the heated profile by the tool holder (3), and then heated when in position, to be embedded in place when the side walls are folded inwards. The cladding foil covers the folded profile surface, and a stiffening web can be welded in place by two layers of weldable material. The insert can have an L-shaped cross section, or cylindrical, and its outer surface can be splined. The insert can also be a spiral. An Independent claim is included for a folded profile body, where an insert at the fold can be of metal or a synthetic materials.

Description

 The invention relates to a method of folding a composite profile comprising a hollow body whose contour is almost closed, in particular made of synthetic material, having approximately parallel opposite walls connected by edges, and a covering sheet fixed against a wall. of the body and the chanting regions close to this wall.

It also relates to the profiles folded by this process.

 In view of a certain number of applications, and in particular for producing bracing frames for the two panes or windows of double-glazed windows, it is necessary to bend a composite profile comprising a hollow body whose outline is completely closed or almost, made of synthetic material, with a wall coated with a sealing sheet, so as to constitute a frame of polygonal shape, generally but not necessarily rectangular.

 According to a known method, in each part of the profile in which a fold must be produced, a wall is formed in a wall thereof, having a triangular or trapezoidal section such that a fold can be formed at the angle desired, for example at a right angle, where the notch is located inside the angle, without the material tending to hinder bending. However, with this method, the profile has a zone of weakness at the fold.

 The object of the invention is to remedy this drawback by creating a folding process which can be implemented easily and which allows the manufacture of folded sections having good robustness.

 To this end, the invention relates to a method of folding a composite profile comprising a hollow body whose contour is almost closed, having approximately parallel opposite walls connected by edges, and a covering sheet fixed against a wall of the body and edge regions close to it, characterized in that a part of the profile is heated in which a fold must be made, with a temperature gradient extending from the sheet to the wall opposite to that at which the sheet is fixed, we press in this part a hot forming projection against this opposite wall to locally bring it closer or put it in contact with the wall to which the sheet is fixed and thus form the region of the future fold, we remove the projection, and, maintaining the edges of the profile to prevent them from deforming laterally thereon, at least one of the parts of the profile which are on either side is pivoted of the region formed, to form in this region formed a fold along a fold line extending transversely to the walls of the body at approximately the limit of the sheet on the edges.

 Thanks to the fact that the material is not cut at the fold, no tear initiation is created in the profile.

The method according to the invention can also have one or more of the following characteristics
- in the part of the composite profile in which a fold must be produced, the body is heated to a temperature at most equal to that at which the material which constitutes it becomes soft
- the edges of the profile are maintained to avoid their lateral deformation, when pressing the forming projection
- we begin to maintain the edges of the profile to avoid their deformation, after the approximation or bringing into contact of the wall opposite the coating and the wall provided with the coating
- the location of the fold line is determined by aligning a fold hinge pin opposite the desired location for this fold line
- the fold line is determined at approximately the limit of the sheet on the edges of the body, in an area covered by the sheet
- the fold line is determined at approximately the limit of the sheet on the edges of the body, in an area which is not covered by the sheet
- after the constitution of the fold, at least the region of it is cooled
- several operations are carried out simultaneously on the same profile, and more particularly at least one part of the profile is heated, while a projection is pressed on at least one other hot part of the profile then a fold is formed in this other part
- the profile is scrolled and immobilized in successive positions of a folding installation in which respectively, the profile is heated, it is pressed on a wall of the body and a fold is formed in the profile, and the fold region
- On the same station of a folding installation, successively, a part of the profile is heated, then a projection is pressed on this part, and a fold is formed in this part.

 The invention also relates to a profile comprising a hollow body whose contour is closed or almost closed, having approximately parallel opposite walls connected by edges, and a covering sheet fixed against a wall of the body and the regions of the edges close to this wall. , characterized in that it comprises at least one fold so that the fold determines an angle, the covering sheet being situated inside the corner, and the wall of the body opposite to that to which the sheet is fixed inside the corner a fold comprising two thicknesses of material welded against each other or in close proximity by forming a stiffening rib extending in the direction of the wall to which the sheet is fixed.

This profile may also have one or more of the following characteristics
- It comprises a fold line extending transversely to the walls of the body at right angles to the limit of the sheet on the edges of the body, in an area covered by the sheet; and
- It has a fold line extending transversely to the walls of the body at approximately the limit of the sheet on the edges of the body, in an area which is not covered by the sheet.

Other characteristics and advantages of the invention will emerge from the following description of modes and embodiments of the invention given by way of nonlimiting examples and illustrated by the accompanying drawings in which
FIG. 1 is a cross section of a profile capable of being folded by the method according to the invention,
FIG. 2 is an external side view of part of the profile of FIG. 1 and of a tool for implementing the invention before the start of a folding operation,
FIG. 3 is a longitudinal section of the profile with the tool of FIG. 2 during the action of this tool on the profile,
FIG. 4 is a longitudinal section of the part of the profile of FIGS. 2 and 3 in which a fold has been made at right angles, and
FIG. 5 is an external side view corresponding to the longitudinal section of FIG. 4.

 The composite profile intended to be folded by the method according to the invention and represented in FIG. 1 comprises a hollow body 1, the outline of which, here completely closed, has an approximately rectangular cross section, with two opposite approximately parallel walls 11, 12 connected by edges 13, 14. This profile body is made of synthetic material, for example a thermoplastic resin, extruded, and it is provided with a sealing coating in the form of a sheet 2 here made of aluminum, fixed against the one of its walls and the edge regions 13, 14 close to this wall 11. The width of the walls is of the order of a few millimeters to a few tens of millimeters depending on the application envisaged, and the edges extend over a height of a few millimeters.

 The aim of the process is to bend this composite profile at a desired angle, for example at a right angle, so that the covering sheet 2 is situated outside the angle.

 According to the invention, with a view to folding, the part of the section provided with its sealing sheet is heated, in which a fold must be produced, ensuring that there is a temperature gradient extending from the sheet. of coating 2 to the wall 12 opposite to that to which the sheet is fixed, the optimum folding temperatures for the synthetic material of the profile and for the sealing sheet being different. The temperature gradient which therefore depends on the nature of the materials constituting the body 1 and the covering sheet 2, thus has the role of preventing one or both of the two components from being at a temperature distant from the range of temperatures at which it has a ductility allowing folding without cracks or cracks.

 Preferably, the heating should not bring the body to a temperature at which the synthetic material which constitutes it becomes soft, in order to avoid undesirable spontaneous deformations, and not to interfere with its actuation from one station to another (here in the direction of the arrow in Figure 2) in the folding installation.

 To prepare the formation of the fold, use a tool 3 comprising a forming projection 4 here of generally prismatic shape with approximately triangular or ogive section, which is arranged so that the length of the prism extends transversely to the walls 11, 12 of the body of the profile, on the side of the wall 12 opposite to that which is provided with the covering sheet, this length of the prism being approximately equal to the width of the walls 11, 12.

 The composite profile being hot with a temperature gradient as mentioned above, as well as at least the projection 4 for forming the tool if not all of it, the hot projection is pressed against the wall 12 of the profile opposite to the covering sheet 2, and thus this wall 12 is pushed back to locally bring it close to or bring it into contact with the wall 11 to which the covering sheet is fixed, to form the region of the future fold. Then remove the tool with its projection 4.

 The edges 13, 14 of the profile being maintained by means of shaping elements (not shown in the diagrams), to prevent them from deforming laterally thereon, one of the two parts of the composite profile is pivoted which are on either side of the region shaped for folding, or the two parts, to constitute in this region shaped a fold along a fold line 5 (which can be seen at the end in FIGS. 4 and 5) extending transversely to the walls 11, 12 of the body, approximately at the right of the limit of the covering sheet 2 on the edges 13, 14 thereof.

 The shaping elements, for example in the form of guides forming a corridor, which hold the edges 13, 14 of the profile to prevent their deformation in a direction transverse to the walls of the body during the actual folding, can be applied against the edges only after bringing together or bringing into contact the wall 12 opposite the covering 2 and the wall 11 provided with the covering, or before contact of the forming projection 4 with the profile, so as to avoid lateral deformation of the edges when the the projection of the forming tool is supported.

 The location of the folding line 5 is defined by means of the folding device (not shown in the diagrams) which pivots at least one of the parts of the composite profile which are on either side of the region put in place. form for folding. This folding device comprises an articulation having a folding articulation axis, and it is arranged in such a way that this articulation axis extends orthogonally to the longitudinal direction of the profile and parallel to the walls of the body facing each other. screw of the desired location of the edges of the profile, to the right of which extends the line designated by the term fold line.

 In order to obtain a sharp fold, it would be necessary for this fold line 5 to be as close as possible to the part of the covering sheet 2 which covers the wall 11. However, taking into account the fact that the covering sheet also covers a certain region of the edges 13, 14, a fold line which would be located at the level of this covered region and very close to the part of the covering sheet 2 which covers the wall 11 would weaken the sheet and could be at the origin of 'a crack of it. For this reason, the fold line 5 extends transversely to the walls of the body at right angles to the limit of the sheet 2 on the edges 13, 14 thereof, whether in an area of the edges which is covered by the sheet, or in an area that is not covered.

 Thanks to the fact that the two walls 11, 12 of the body are brought into contact or brought into contact, no tear initiation is created, and, furthermore, as a result of folding, the wall of the body opposite the sheet present in the fold region, a fold 15 comprising two thicknesses of material which can be welded against each other or in close proximity; this folding determines a stiffening rib extending towards the wall 11 to which the sheet 2 is fixed and more precisely from the top of the folding angle, and these two thicknesses of material also constitute a stop opposing up to to a certain limit to accidental folding beyond the folding angle determined by the shape of the projection 4 of the forming tool 3.

 After the fold is formed, to accelerate the return of the profile to a temperature at which it can be handled without special precautions, the region of this fold can also be cooled.

 In the case of the application of the method to the production of polygonal frames, for example rectangular, it is necessary to form several folds along the same section of profile; in order to reduce the manufacturing time of the frame, it is advantageous to carry out several operations simultaneously on the same profile, and for example one or more parts of the profile are heated, while a forming projection is supported on one or more other hot parts where a fold is formed immediately.

 For example, the profile is scrolled and immobilized in successive stations of the folding installation in which respectively, the profile is heated, it is pressed on a wall of the body and a fold is formed in the profile, and cools the fold area.

 It is also possible on the same station, successively, to heat a part of the profile, then to support a projection, and to constitute the fold in this part.

 Thanks to this process, it is possible to fold profiles comprising two elements constituted respectively by a hollow body made of synthetic material and a sheet of sealing coating, for example of aluminum strip fixed to a wall of the body and the regions of the edges. close to this wall, quickly and reliably.

Claims (13)

 1. Method for folding a composite profile comprising a hollow body (1) whose contour is almost closed, having approximately parallel opposite walls (11, 12) connected by edges (13, 14), and a sheet of covering (2) fixed against a wall (11) of the body and the edge regions (13, 14) close to it, characterized in that a part of the profile is heated in which a fold must be made, with a temperature gradient extending from the sheet (2) to the wall (12) opposite to that to which the sheet is fixed, in this part is pressed a hot forming projection (4) against this opposite wall (12) for locally bring it closer or bring it into contact with the wall (11) to which the sheet is fixed and thus form the region of the future fold, the projection (4) is removed, and, maintaining the edges (13, 14) of the profile to prevent them from deforming laterally to it, we rotate at least one of the parts s of the profile which are on either side of the region formed, in order to constitute in this region formed a fold along a fold line (5) extending transversely to the walls (11, 12) of the body approximately at right angles to the edge of the sheet (2) on the edges (13, 14).  2. Method according to claim 1, characterized in that in the part of the composite profile in which a fold must be produced, the body (1) is heated to a temperature at most equal to that at which the material which constitutes it becomes soft .  3. Method according to any one of claims 1 and 2, characterized in that the edges (13, 14) of the profile are maintained to avoid their lateral deformation, when one presses the forming projection (4).  4. Method according to any one of claims 1 and 2, characterized in that one begins to maintain the edges (13, 14) of the profile to avoid their deformation, after the approximation or the bringing into contact of the wall ( 12) opposite the covering (2) and the wall (11) provided with the covering.  5. Method according to any one of claims 1 to 4, characterized in that one determines the location of the fold line (5) by aligning a fold hinge axis vis-à-vis the 'desired location for this fold line.  6. Method according to any one of claims 1 to 5, characterized in that one determines the fold line (5) at approximately the limit of the sheet (2) on the edges (13, 14) of the body (1), in an area covered by the sheet.  Method according to any one of Claims 1 to 5, characterized in that the fold line (5) is determined approximately at the edge of the sheet (2) on the edges (13, 14) of the body ( 1), in an area that is not covered by the sheet.  8. Method according to any one of claims 1 to 7, characterized in that, after the constitution of the fold, at least the region thereof is cooled.  9. Method according to any one of claims 1 to 8, characterized in that several operations are carried out simultaneously on the same profile, and more particularly at least part of the profile is heated, while a projection is pressed. (4) on at least one other hot part of the profile then a fold is formed in this other part.  10. Method according to claim 9, characterized in that the profile is scrolled and immobilized in successive positions of a folding installation in which respectively, the profile is heated, it is pressed on a wall (12 ) of the body and a fold is formed in the profile, and the region of the fold is cooled.  11. Method according to any one of claims 1 to 9, characterized in that, on the same station of a folding installation, successively, a part of the profile is heated, then a projection (4) is pressed on this part , and there is a fold in this part.  12. Profile comprising a hollow body (1) whose contour is almost closed, having approximately parallel opposite walls (11, 12) connected by edges (13, 14), and a covering sheet (2) fixed against a wall (11) of the body and the regions of the edges close to this wall (11), characterized in that it comprises at least one fold so that the fold determines an angle, the covering sheet (2) being located at outside the corner, and the wall (12) of the body (1) opposite to that to which the sheet is fixed has inside the corner a fold (15) comprising two thicknesses of material welded to it one against the other or in close proximity by forming a stiffening rib extending in the direction of the wall (11) to which the sheet (2) is fixed.  13. Profile according to claim 12, characterized in that it comprises a fold line (5) extending transversely to the walls (11, 12) of the body (1) at approximately the limit of the sheet (2) on the edges (13, 14) of the body (1), in an area covered by the sheet.  14. Profile according to claim 12, characterized in that it comprises a fold line (5) extending transversely to the walls (11, 12) of the body (1) at approximately the limit of the sheet (2) on the edges (13, 14) of the body, in an area which is not covered by the sheet.