DE202005012029U1 - Ultrasonic unit to thermo-fix and/or polish woven and/or fiber strip materials, for motor vehicle safety belts, has a passage opening between the sonotrode and anvil with an exit width equal to the workpiece final width - Google Patents

Abstract

The assembly (1) to thermo-fix and/or polish the woven and/or fiber structure of a workpiece (W) has an ultrasonic unit (2) to generate the required energy. At least one sonotrode (3) is at one side of the workpiece, with an anvil or a second sonotrode at the other side. The workpiece travels (V) through the gap (S) between them. The anvil or the second electrode has an opening with an exit width equal to the final workpiece width.

Description

The Invention relates to a device for thermosetting for Deformation and / or smoothing the weave and / or fiber structure of a workpiece, in particular a rope, band or web-shaped Workpiece with an ultrasonic device for generating ultrasonic vibrations for introducing the heat-setting for deformation and / or smoothing the weave and / or fiber structure of the rope, band or web-shaped workpiece required energy, wherein on the first side of the workpiece at least one sonotrode and a second side of the workpiece, opposite the sonotrode, an anvil or another sonotrode is arranged.

Heat-setting devices are known and serve the dimensional stability of synthetic fibers and tissues trained workpieces to improve and protect against unwanted shrinkage. The Thermofixation of such workpieces is carried out in such a way that this workpieces in a warming room be introduced, with temperature and residence time by the type the fiber can be determined. Preferably takes place in the heat chamber still an extension of the workpieces, by providing that the Entry speed of the band or web-shaped workpieces smaller is as their exit speed. After going through this warmth rate will be in the heat chamber reached state fixed by placing the workpiece in a cooling stage becomes.

The known devices for heat setting for deformation and / or smoothing have the weave and / or mesh structure of such workpieces the disadvantage that the each used heating chambers require a lot of space, which disadvantageously leads to known heat-setting devices build voluminous.

One Another, even more serious disadvantage is that the heating chambers require a long preheating time and / or a long cooling time. This results in disadvantageous Way to that at a defect, in particular in a tearing of the band or web-shaped workpiece in the Heating chamber, this cooled first Need to become, before it is possible is to remedy the defect, in particular a new workpiece web in to introduce the heating chamber. At this conversion process includes Then turn in a disadvantageous way a renewed heating the one for conversion cooled heating chamber at.

One Another disadvantage of the known thermofixing devices for deformation and / or smoothing the weave and / or mesh structure of a workpiece is that they have a relatively high energy consumption, not least because of that the Heating chambers voluminous build, so that for an appropriate Heat load of the workpiece not only the energy needed which is required to treat the workpiece, but about that There is still a big one out there Proportion of needed Total energy to heat the chambers is to spend.

The EP 1 283 294 Applicant proposes to avoid the disadvantages of the above-mentioned devices for thermosetting that the energy required for thermosetting the workpiece is provided by ultrasonic vibrations. Such a device is characterized by its low energy consumption, since it is no longer necessary by the introduction of heat energy by ultrasonic vibrations to use voluminous building and energy-consuming heating chambers. Furthermore, it is no longer necessary to preheat the heat-setting device for deforming and / or smoothing the weave and / or mesh structure, since it is possible to direct the ultrasonic vibrations generated by a sonotrode of an ultrasound device directly to the workpiece. Since it is also no longer necessary to heat or cool heating chambers, no preheating or cooling times are to be taken into account in the implementation of the method, so that rapid retooling and rapid workpiece replacement, in particular in the case of defects, are easily possible.

At the Thermofixing of woven or knitted, rope, web or strip-shaped workpieces reduced their width: typically is at a starting width of 50 mm, the bandwidth of the heat-set workpiece about 47 mm. Furthermore, the output width of such a workpiece varies from Loom to loom, since the initial width of the voltage curve in the chain and of various others occurring during weaving Factors dependent is. Also depends the final width of such a heat-set workpiece thereof whether stretched, held or shrunk during thermosetting becomes. Thermofixed workpieces therefore have a certain width tolerance.

It Object of the present invention, a device of the initially so-called type such that a reduction in the tolerance of Final width of the heat-set workpiece is achieved.

To achieve the above object, it is provided in the device according to the invention that the anvil and / or the further sonotrode has a recess whose output-side width is substantially equal to the final width of the heat-set workpiece.

By the measures according to the invention will achieved in an advantageous manner that the width tolerance of rope, strip or web-shaped, heat-set workpieces is reduced in an advantageous manner. This particular for workpieces, in safety-relevant facilities, such. B. in restraint systems for vehicles, to be used, an advantage.

advantageous Further developments of the invention are the subject of the dependent claims.

Further Details and advantages of the invention are the embodiments to be taken, which are described below with reference to the figures. Show it:

1 FIG. 2 is a schematic front view of a first embodiment of a device for carrying out a heat-setting process, FIG.

2 the device of 1 in a side view,

3 the device of 1 and 2 in a plan view,

4 a top view of an ultrasonic device together with a workpiece,

5 a front view of the 4 .

6 a section along the line AA the 4 .

7 a second embodiment of the device in a front view, and

8th the second embodiment in a plan view,

The device for heat setting for deformation and / or smoothing of the weave and / or mesh structure of rope, band or sheet-like workpieces having fibers with a semi-crystalline, over-molecular structure, will now be described in the following with reference to the 1 to 3 illustrated schematically first embodiment.

The generally with 1 designated device is in principle divided into a known per se and therefore no longer described ultrasonic device 2 with a sonotrode 3 which over an anvil 4 is arranged. In a gap S between sonotrode 3 and anvil 4 which during the operation of the ultrasonic device 2 when elastic workpieces W preferably kept constant and is delivered to non-elastic workpieces W for pressurizing the workpiece W, the heat-setting workpiece W is feasible and by the sonotrode 3 emitted ultrasonic vibrations can be acted upon with ultrasonic energy.

In the 1 - 3 not shown is a known per se feeding device in which the rope, band or web-shaped workpiece W to be treated is received and the workpiece W at a defined feed rate of the device 1 supplies, as well as a Abtransporteinrichtung whose working speed is less than or equal to the feed rate, so that the band or web-shaped workpiece W as it passes through the device 1 is stretched or shrunk or kept equal due to the different or the same speeds of the two aforementioned transport devices.

The energization of the workpiece W by the sonotrode 3 emitted ultrasonic vibrations now leads to a heating of the fibers of the workpiece W, which causes the molecules of the fibers to align and thus the known advantages of for the purpose of deformation and / or smoothing of the woven and / or fiber structure heat-set workpieces are achieved.

Now, if the inlet velocity of the workpiece is smaller than its outlet speed, the workpiece is stretched between the two transport devices and the workpiece is in the range of the ultrasound applied by the sonotrode 3 under a more or less strong tension. This, in conjunction with the ultrasound application, results in alignment of the molecular structure of the workpiece to be treated.

is now the inlet velocity equal to the outlet velocity, this is the workpiece in the field of ultrasound application under a uniform voltage, whereby a solidification and / or a smoothing of the surface of the workpiece can be achieved is.

in the Case of one opposite the discharge speed greater inlet velocity, So with a tension-free workpiece transport, the workpiece is in the ultrasonic range shrunk. This makes it possible in an advantageous manner, the to reduce or eliminate so-called washing or in workpiece W get a certain amount of stretch.

By the above measures, the weave and / or mesh structure is caused by the ultrasonic treatment in its structure and / or becoming more uniform in their structure. Production-related differences of the workpiece material can thereby be compensated in an advantageous manner and the tendency of the workpiece to roll up, is reduced.

The use of ultrasonic vibrations to supply the energy required for thermosetting the workpiece W has the advantage that the described device consumes only a fraction of the energy, as in the case of known devices in which the heat application of the workpiece W takes place in a heating chamber, the case since the energy required for thermosetting the workpiece W in an advantageous manner directly over that of the sonotrode 3 emitted ultrasonic vibrations is supplied and not - as in known devices - indirectly by a heating chamber is heated. This direct, direct energy input of the ultrasonic energy through the sonotrode 3 furthermore has the advantage. that in the described device in an advantageous manner no heating times occur. Since the supply of the ultrasound energy required for thermosetting through the sonotrode 3 , which does not heat itself significantly, is feasible in the device 1 No cooling times to observe, so that a quick retooling is easy to carry out.

As in the 4 to 6 illustrated, it is provided that the anvil 4 the ultrasonic device 2 a recess 10 , which is formed in the case shown here as a groove, whose output-side width 10 ' is substantially equal to the final width of the heat-set workpiece W is. The side walls of the recess 10 form lateral guides 10a . 10b for the workpiece W and cause that from the ultrasonic device 2 exiting, heat-set workpiece W has a defined end width. In addition, this solidification of the tissue is achieved and the lateral guidance of the workpiece W also causes a more advantageous distribution of the ultrasonic effect and the introduced ultrasonic energy in an advantageous manner. The lateral guidance of the workpiece W also has an advantageous effect on the transverse rigidity of the workpiece W.

How best of the 4 it can be seen, it is provided that the inlet-side width 10 '' the recess 10 greater than the bandwidth of the heat-setting workpiece W is and the width of the recess 10 continuously to the output width correlated with the end width of the heat-set workpiece W 10 ' narrows. Such a configuration has the advantage that in this way a continuous reduction of the bandwidth of the workpiece W can be achieved in a simple manner.

In the 7 and 8th is a second embodiment of a generally with 1' designated device, which differs from the device 1 of the first embodiment of 1 - 5 differs in that instead of the anvil 4 a second ultrasonic device 2 ' is arranged, the structure of which is substantially that of the ultrasonic device 2 corresponds, so that the workpiece W from both sides, from a first side W of the sonotrode 3 the ultrasonic device 2 and from a second side W "of the sonotrode 3 ' the ultrasonic device 2 ' can be acted upon with ultrasonic energy. Such a measure has the advantage that in this way a double-sided treatment of the workpiece W is made possible in a particularly simple manner.

The second sonotrode 3 ' has (not shown) in its working surface a recess 10 on, whose configuration corresponds to that of the first embodiment, so that reference can be made to the above statements to avoid repetition.

In the two embodiments described above, it is assumed that the heat-setting of the rope, web or strip-shaped workpiece W by a sonotrode 3 or by two opposing sonotrodes 3 . 3 ' is carried out. But it is possible that in the feed direction V of the workpiece W in series more sonotrodes 3 . 3 ' again to be arranged either only on one side W or W "of the workpiece W or on both sides W, W ', so that the heat-setting operation of the workpiece W on several ultrasonic devices 2 . 2 ' is distributed.

This allows it, on the one hand with a lower ultrasonic energy per sonotrode to work, thereby causing the by the Ultraschallalletrag caused thermosetting to deformation and / or smoothing of Web and / or mesh structure of the workpiece W essentially only on the surface of the workpiece W limited remains, resulting in a smoothing the surface and thus an increase the abrasion resistance achieved with otherwise unchanged material structure becomes. Furthermore This allows a gentler treatment of the workpiece.

On the other hand, it allows the above-described arrangement of several sonotrodes 3 . 3 ' one behind the other, to increase the intensity of the ultrasound entry, whereby, inter alia, an increase in the operating speed of the device can be achieved.

In the above description, it was assumed that the sonotrodes 3 . 3 ' or the sonotrodes 3 and the opposite Am boss 4 is arranged spaced apart with gap. It is of course also possible to reduce this gap to a lesser extent, so that the between the two opposite sonotrodes 3 . 3 ' or between a sonotrode 3 and the anvil opposite her 4 Guided workpiece W a more or less intense pressurization by the sonotrodes 3 ' . 3 is suspended. Such a measure causes a "ironing effect", whereby the smoothing of the surface and the associated improvement in abrasion resistance can be enhanced.

By approaching at least one sonotrode 3 . 3 ' to the workpiece W, the energy input into the workpiece W can be increased, resulting in an advantageous manner, a higher operating speed.

Preferably, it is also provided that in the device 1 a regulation of the amplitude of the ultrasonic vibrations takes place in such a way that the amplitude of the ultrasonic vibrations is reduced when the sonotrodes 3 . 3 ' expand by heating, so that in an advantageous manner a set energy / path window is maintained.

Surprisingly it turned out that one Humidification of the workpiece to improved results in thermosetting for the purpose of deformation and / or smoothing the weave and / or mesh structure of the workpieces leads.

Another advantage is that it is provided that the working surface of the sonotrodes 3 . 3 ' coated with Teflon. This leads in an advantageous manner to an increase and alignment of the energy input.

To conclude yet mentioned be that the Device described in particular for the production of belts for motor vehicle restraint systems are suitable.

Claims (5)

Device for thermosetting for deforming and / or smoothing the weave and / or fiber structure of a workpiece (W), in particular a rope, belt or web-shaped workpiece (W), with an ultrasonic device ( 2 ) for generating ultrasonic vibrations for introducing the heat for fixing and / or smoothing the weave and / or fiber structure of the rope, band or web-shaped workpiece (W) required energy, wherein on the first side (W ') of the workpiece ( W) at least one sonotrode ( 3 ) and a second side (W '') of the workpiece (W), the sonotrode ( 3 ) opposite, an anvil ( 4 ) or another sonotrode ( 3 ' ), characterized in that the anvil ( 4 ) or the further sonotrode ( 3 ' ) a recess ( 10 ) whose output-side width ( 10 ' ) is substantially equal to the final width of the heat-set workpiece (W). Apparatus according to claim 1, characterized in that the inlet-side width ( 10 '' ) of the recess ( 10 ) is greater than the width of the thermo-fixing workpiece (W). Apparatus according to claim 2, characterized in that the sonotrode ( 3 ) and the anvil ( 4 ) or the further sonotrode ( 3 ' ) are separated by a gap (S). Device according to one of the preceding claims, characterized in that the device has at least two sonotrodes ( 3 . 3 ' ), which are arranged one behind the other in the feed direction (V) of the workpiece (W). Device according to one of the preceding claims, characterized in that at least one sonotrode ( 3 . 3 ' ) has a coating of Teflon.