EP1597940B1 - Method and device for placing threads on a plastic substrate - Google Patents

Abstract

The invention relates to a method for placing threads on a plastic substrate,which is fixed to a support, particularly in the form of a drum, and which is moveable with the aid of a first drive,with the aid of at least one placement unit which is used to place the thread on the surface of the substrate,which is moveable with the aid of a second drive, in relation to the moveable support and independently thereof on the surface of the substrate. According to the invention, a reversible positioning drive, preferably a direct electric drive such as a torque motor, is used as a first drive in order to position the support. At least one linear motor with a guiding device for at least one cursor is used as a second drive for positioning the at least one placement unit. The inventive method and device for the implementation thereof enable, for example, the creation of occupation fields, diverging from a rectangular surface and/or the placement of threads having irregular undulations (lengths, amplitudes).

Description

The invention relates to a method and a device for laying wires on a plastic substrate, having the features of the preamble of claim 1. It also relates to a device that is particularly suitable for carrying out the method .

It has long been known to integrate in window panes for vehicles or buildings heaters, antennas, decorations or also anti-radiation screens, which are essentially formed of electrically conductive wires, which are mechanically deposited on an adhesive layer of the laminated pane according to a predetermined pattern. For the electrical contact of these wires to the outside (arrival of the heating voltage, transfer of antenna signals), both ends are generally provided with collecting conductors, which are electrically connected to all the wires. by soldering, by electrically conductive adhesives or the like.

US-A-5 891 280 discloses a method of laying thin threads and the corresponding device, with which the threads are laid on an adhesive film or the like. The method is characterized in that the films to be lined are fixed on a rotating drum, which serves for the positioning of the films under a laying unit, which is movable in a reciprocal movement parallel to the axis of the rotary drum, with a large positioning accuracy in the manner of a drawing table. Thus, the wires can in principle be deposited on tracks in any case, in particular also curves, and their mutual spacings need not necessarily remain constant. The direction and speed of rotation of the drum, however, remain constant.

The laying unit is moved in a reciprocal movement by means of a longitudinal spindle drive, which allows precise positioning, but which is in principle relatively slow in the case of large movements. The method can also be used to connect yet collector conductors on the drum with the wires, and to cut them.

An older device known from DE-A1-42 01 620, for laying fine wires on a thermoplastic film, comprises one or more laying units which can / can be moved again in the direction of the The axis of a rotating drum carrying the film, in which, however, the yarns are finally wound helically around the drum. In the finished product, this is not a problem because of the very low angle of inclination between the wires laid at very short distances from one another. This process works in the end faster than the technique mentioned above, but it does not allow the laying of son following a contour.

The two types of known devices have in common that the films are fixed on the drums by the application of a pressure difference; the side surfaces of the drums are perforated, and the pressure in the interior space of the hollow drum is reduced with respect to the atmospheric pressure by an air suction.

It is also known to deposit wires on a stationary still support using a device similar to a drawing table. Although this device can produce virtually any deposit lines, it is nevertheless relatively slow.

EP-B1-613 769 discloses a method for cutting heating wires deposited continuously on a substrate, while EP-B1-656 257 discloses a method for electrically contacting the heating arranged parallel to each other with collector conductors oriented transversely to them.

The object of the invention is to provide a method which brings together the advantages of the known devices, which in particular allows a high speed of laying while following patterns in a flexible manner, and of proposing a device which is particularly suitable for the implementation of the invention. process.

According to the invention, this problem is solved with respect to the method by the features of claim 1. The features of claim 11 indicate a corresponding device. The features of the sub-claims subordinate to the respective independent claims show advantageous embodiments of these inventions.

A particular characteristic of this process according to the invention consists in that the support is now reversible (with reversal of the direction of advance or rotation) and also that it is driven with an adjustable speed. In this way, possibilities are clearly widened, on the one hand for laying the wires on the substrate, and on the other hand for the use of other tools. For this purpose, a flat or curved support with a mass as small as possible can be used which can be driven and positioned very precisely with the aid of a positioning drive, preferably a direct drive without play with very short reaction. Such direct trainings are in themselves known. It is not absolutely necessary that they be operated electrically, but one can also use hydraulic or pneumatic positioning drives.

Instead of the preferred gearless direct drive, it would also be possible to use a drive with a gear distribution and appropriate compensation of the possible play.

This first step according to the invention is completed by the use of a linear drive fast and precise, preferably electric, for the movements of the tools transversely to the direction of movement of the support. For this linear drive at least one guide rail is required with the driving magnets and at least one slider serving as a tool carrier or as configured as such.

It is then possible to have several cursors on the same guide rail and / or to provide several guide rails distributed on the work surface. If necessary, the functions of the tools (laying, electrical connection, cutting of the son and possibly the substrate) can be distributed on different guide rails respectively on several linear drives.

Unlike the case of the previous application, however, it is also possible to use fluid-driven servomotors (pneumatic or hydraulic) as linear motors which can, with their control members, each time position a tool or several tools in a synchronous manner and parallel to each other. In this way, it is possible to achieve high adjustment speeds and precise positioning.

The complete control of the machine can be programmed, so that, to change a laying pattern, only the current control program must be modified.

With such a way of proceeding and such a laying technique, it is also possible to make specific laying patterns for the customers, for example the laying of a set of threads in a generally corner shape, that is to say that the wires finally cover a substantially trapezoidal surface, because they are not laid exactly parallel as before, but with small inclinations relative to each other. This effect can also be achieved by orienting the yarns, for example, exactly parallel to one another as before in the central area of the surface and by placing partial quantities of yarns in the edge regions of the non-rectangular surface. to garnish, with a constant intermediate angle, variable or progressively increasing between neighboring son.

It is thus possible to satisfy the demands of customers, for example in the automotive industry, who desire a surface occupation such that heating of the entire surface is possible, in parts, substantially trapezoidal developing, of the surface of -brise or rear glasses, even when the heating son extend between the two long sides (in mounted position between the upper edge or roof and the lower edge) of such panes.

According to yet another embodiment of the method, the waviness amplitude of the laid wires may finally be variable. It is certainly known in itself to lay the son in corrugated lines, however it is obtained with the known means (in which the son are deformed plastically between two toothed wheels in engagement immediately before laying on the substrate) only a uniform corrugation, even if it is visually very unclear and the wires are well hidden from view.

With the method according to the invention, on the contrary, the corresponding devices make it possible, by a suitably coordinated control of the advances of the laying units and the support, to lay the wires also in waves with variable wavelengths and / or amplitudes. . In this way, it is also possible to influence, within wide limits - by laying more or less long lengths of wire - the resistances and thus also the heating power of individual wire lines, without having to use a material made of wire of different sizes / thicknesses or with different specific resistances. In particular, a wire, which must pass only a relatively short distance between the collecting conductors in the case of a predetermined window contour, can acquire by a suitable corrugation (with a longer effective wire length as a result) a active resistance which is equal to the resistances of the "longer" wires visually mounted electrically in parallel, or in any case at least close to them.

This request can be met by replacing the mechanical drive of the known laying units, for example by stepping motors or other suitable servocontrols. The control of these drives / stepper motors is naturally synchronized with the control of the support. This produces a variable electronic distribution.

The Z axis of the movement of the tools, that is to say its component oriented more or less perpendicularly to the working surface, respectively to the surface of the substrate, can be set in translation or in rotation. For this latter variant, it can for example be provided a hollow shaft electric drive, which can first be moved and positioned along a rectilinear guide, and which can pivot about this axis in translation or an axis parallel thereto for the action of a tool that it carries, for example a cutting tool or marking.

Cutting tools can be integrated in the device both for the lengthening of the laid wires themselves (clamps, short circuit electrodes) and for cutting the substrate, for example a thermoplastic adhesive film (knife) , and be controlled with the process according to the invention. It is also possible, for example, to combine a laying unit with a cutting tool, so that after the laying of a defined length of wire, it is immediately cut conveniently before starting the laying of the wire. next (possibly neighbor). In this case, it would also be possible, unlike the known methods and devices, to pose in opposite directions of installation of the wires to be laid one after the other.

If desired, it is also possible to produce a sinuous line of the son without interruption and without transformation of the device.

Other details and advantages of the subject of the invention will become apparent from the following detailed description of an exemplary embodiment.

la Figure 1

montre une vue latérale d'un dispositif pour la mise en oeuvre du procédé conforme à l'invention ;

la Figure 2

montre une vue en plan d'un dispositif analogue.

In the appended schematic drawings, greatly simplified of the embodiment example,

Figure 1

shows a side view of a device for carrying out the method according to the invention;

Figure 2

shows a plan view of a similar device.

In FIG. 1, a rotary drum-shaped support 1 is provided with a reversible electric direct drive 2, which acts on an axis of rotation 3 of the support 1 fixedly mounted in a frame and which can, on the one hand, drive this one around this axis of rotation 3 in both directions of rotation and on the other hand to control and position it in predetermined movement patterns. A plastic substrate 4 is fixed on the surface of the support 1 with adequate means (of a known nature).

Above the support 1, two laying units 5 of the same type have been indicated. They are intended to lay thin wires 6 on the plastic substrate 4. They are fixed on sliders 7, which can slide along guide rails 8 fixed to the frame, perpendicular to the plane of the drawing.

It is further shown schematically another tool 5 'on the left side, next to the support. This is guided on a cylindrical guide rail 8 ', and its slider 7' has a bore adapted to the guide rail 8 '. This slider can not only slide along the guide rail 8 ', but it can also pivot around it (hollow shaft pivot drive), so that the corresponding tool 5' can also perform a movement of lifting (pivoting) around it with respect to the support 1 and the plastic substrate. It is thus adjustable back and forth between a rest position (raised, drawn in solid lines) and a working position (in contact with the plastic substrate, drawn in phantom). The tool may for example be a heating tool, a cutting tool and / or a writing tool and it then comes into contact with the plastic substrate only when its function is really necessary.

Naturally, the laying units 5 can also be adjustable in height relative to their slider 7, in particular to bring them with their blocks 9 in the exactly correct position above the surface of the substrate, and further to facilitate the exchange of wire coils and insertion of new wires 6.

FIG. 2 further illustrates the relative mobility of the laying units 5 and the support 1 with the plastic substrate 4. For simplicity, there is shown in Figure 2 a guide rail 8. This, however, outside the laying unit 5, in addition to the slider 7 two more sliders 7 drawn in phantom with other tools of the type described above. The guide rail 8 extends parallel to the axis 3 and therefore perpendicular to the actual working direction of the support 1.

To the left of the device, there is shown a programmable control unit C, which coordinates the movements of the support 1 and sliders 7 with the installation units and the other tools. It is symbolically connected using control and power lines with the direct drive and the guide rail respectively with the sliders associated with it.

The laying units 5 are suitable for laying the wires 6 in the correct and safe position, independently of the direction of the relative movement between the support on the one hand and the sliders on the other hand. This is reproduced here in a very simplified way because the son 6 are guided by a block 9, whose lower face is placed as close as possible to the surface of the plastic substrate 4.

In order to reproduce at least in part the multitude of independently executable functions, the plastic substrate 4 is here divided into three sections along the width of the support 1 by two pairs of phantom lines drawn vertically.

While quite left a segment of wire 6 deposited on the plastic substrate 4 has been deposited simply in a straight line, even if slightly oblique with respect to the axis 3 of the support, the wire 6 currently manipulated by the laying unit 5 is deposited along a wavy line with increasing amplitude from top to bottom. The general direction in which the corrugated wire extends forms a small intermediate angle with respect to the wire deposited quite left.

This is possible by oscillating back and forth the cursor 7 with the laying unit 5 on the guide rail 8 following the predetermined wavy pattern, as indicated by a double arrow, while the support 1 moves below . Obviously, it is possible to thus lay son in any pattern, either rectilinear or in waves, or in loops or meanders, and parallel and / or with intermediate angles constant or variable between them.

Sinuous paths are possible, if one uses the option of the direct drive 2 to move in oscillation back and forth the support 1 itself (also indicated on the left by a double arrow) and to continue at the same time the laying of a wire 6. This variant is illustrated in the central portion of the plastic substrate 4, where is produced on the edge thereof with the wire 6 a corrugated pattern propagating parallel to the axis 3 support 1, only by the oscillation of the support 1 and at the same time the translational movement of a slider 7 carrying a laying unit in addition to the block 9.

If one still considers the option of superimposing on the oscillating movement of the support an equally oscillating movement of the slider, one can then deposit practically all the patterns of thread on the plastic substrate; these can also be made for a purely decorative purpose, for example without any electrical function.

In the right part of the plastic substrate 4, finally, a cutting line 10, which is made here with the help of another slider 7 equipped with a cutting tool 5 ', for dividing the substrate of material plastic 4.

Claims (19)

1. A method for the laying of heating, antenna and/or decorative wires onto a plastic substrate (4) which is fastened to a support (1), in particular in the form of a drum, moveable with the aid of a first drive (2), with the aid of at least one laying unit (5) intended for laying the wire (6)onto the surface of the substrate, said laying unit being moveable with the aid of a second drive (7, 8) with respect to the moveable support, and independently of the latter, over the surface of the substrate, characterized in that the first drive used is a reversible positioning drive (2) for the positioning of the support (1), and in that the second drive used is at least one linear motor with a guide device (8) for at least one traveler (7) for the positioning of at least one laying unit (5).
2. The method as claimed in claim 1, characterized in that the positioning drive (2) used is a direct electrical drive, in particular a torque motor.
3. The method as claimed in claim 1 or 2, characterized in that a plurality of travelers (7) are used, which can be positioned independently of one another for the positioning of at least one laying unit (5) or of at least one other tool with the aid of one or of a plurality of linear motors.
4. The method as claimed in any one of the preceding claims, characterized in that at least one second guide device for the independent guidance of travelers (7) carrying tools is used.
5. The method as claimed in one of the preceding claims, characterized in that a first guide device is used for the guidance of wire laying units and a second guide device is used for the guidance of other tools, in particular cutting tools.
6. The method as claimed in any one of the preceding claims, characterized in that at least one partial quantity of the wires is laid one next to the other with a nonparallel orientation.
7. The method as claimed in any one of the preceding claims, characterized in that at least one partial quantity of wire parts is laid with a variable waviness, that is to say a variable wavelength and/or amplitude.
8. The method as claimed in any one of the preceding claims, characterized in that at least one partial quantity of wire parts is cut to a suitable length immediately after laying.
9. The method as claimed in any one of the preceding claims, characterized in that at least one partial quantity of adjacent wire parts is laid with the wire parts next to one another in an each time alternate direction.
10. The method as claimed in any one of the preceding claims, characterized in that at least one partial quantity of wire parts is laid in sinuous form without a break.
11. A device for the laying of heating, antenna and/or decorative wires onto a plastic substrate (4), with a support (1), in particular in the form of a drum, moveable with the aid of a first drive (2) for fastening the substrate, and with at least one laying unit (5) intended for laying a wire (6) onto the surface of the substrate, said laying unit being moveable with the aid of a second drive (7, 8) with respect to the moveable substrate, and independently of the latter, reversibly and so as to be capable of being positioned on the surface of the substrate, characterized in that the support (1) can be displaced reversibly and positioned with the aid of a positioning drive (2), and in that at least one laying unit is moveable with the aid of at least one linear motor with a guide device (8) for at least one traveler (7) carrying the laying unit (5).
12. The device as claimed in claim 11, characterized in that the working axis of the linear motor is arranged substantially transversely, preferably at an angle of 90°, with respect to the working direction of the support.
13. The device as claimed in claim 11 or 12, characterized in that the linear motor consists of a drive with fluidic, that is to say pneumatic or hydraulic, control.
14. The device as claimed in claim 11 or 12, characterized in that the linear motor consists of an electrical drive.
15. The device as claimed in claim 14, characterized in that the linear motor has a guide device (8) for a plurality of travelers (7) capable of being displaced and positioned independently of one another.
16. The device as claimed in any one of the preceding device claims, characterized in that, next to at' least one laying unit (5), other tools (5') with other functions, in particular heating tools, cutting tools or writing tools, can also be positioned with the aid of travelers (7) and of linear motors on the substrate (4) and so as to act on the latter and on the wires (6).
17. The device as claimed in any one of the preceding device claims, characterized in that pivoting drives, in particular hollow-shaft drives (7', 8'), are provided for the adjustment of tools in the general working direction perpendicular to the surface of the substrate.
18. The device as claimed in claim 17, characterized in that at least one traveler (7) can both be displaced and positioned in a straight line along a guide device (8) and be tilted about the axis of the guide device.
19. The device as claimed in any one of the preceding device claims, characterized in that the positioning drive is a direct electrical drive, in particular a torque motor.

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