DE8103868U1 - Device for the continuous production of endless, deformable tubes from a strip of laminate film - Google Patents

Description

PATS NTAN WALTE

ZELLENT 5 N
ZWEIIBRÜCKENSTF ?. 15 ⁴

iiOOO MUNICH 2

February 12, 1981
aiv 81038

Device for continuous production
of endless, deformable tubes made from a strip of laminate film

The invention relates to a device according to the preamble of Claim 1.

One such device is

from DE-AS 26 43 089 known. Thereafter, the formed tube formed from a multilayer laminate film tape in the Area of overlap of the edges detected by an outer and an inner belt and a high frequency induction welder fed, where heating is continued until flowable phases are present in the overlap area of the foil edges are. Then the overlap is pressed by means of a squeeze roller over the upper conveyor belt in order to remove the flowable Express phase of the laminate in terms of sealing the exposed edge of the metal foil. Then the sealed one Tube passed through the inner band through a cooling device. Because the outer band has already been removed can be cooled directly from above. This known device can be used to produce pipes of sufficiently good quality produce.

However, those required in the overlap area have become disadvantageous inner and outer conveyor belts proved that

on the one hand prevent effective rapid cooling of the seam area, on the other hand due to their elasticity a Do not allow local pressure loading to the desired extent, so that the seam with different film material does not could always be produced in the desired shape and quality. During operation, the conveyor belts also heat up, which has a negative effect on the stability of the manufacturing process. There is also the possibility of Soiling of the conveyor belts due to the phase flowing out or sticking, so that the belts have to be replaced, which is very laborious, especially with the inner belt. The construction of the mandrel is because of the inner belt complicated. Since the belt must protrude at least far into the cooling zone because of its transport function, the mandrel must also be very long, which brings friction and support problems with it.

From DE-AS 14 79 930 is a similar one

$ f Device for the continuous production of a pipe

a flat sheet of pliable weldable material

by forming an overlap seam to be welded

Ϊ-. knows, in which those described in the generic type

Γ Conveyor belts are welding elements made of thermally conductive material,

ti: with which radial pressure is exerted on the overlap area

js will. An endless belt is also used for transport.

ti, In addition to the disadvantages described in the generic type

the applicant points out in her DE-AS 1 779 266 that there are no satisfactory longitudinal seams on multilayered can produce a sheet material containing metal foil, since the cut edge of the metal foil is not covered can be. In addition, because of the overlap, step-shaped paragraphs form, which impair the appearance. A disadvantage was also stated that due to the need for adequate support of the overlap, on the other hand, however, on condition that the friction does not become too great, it is not possible to achieve satisfactory feed speeds permit.

According to the suggestion for improvement in DE-AS 1 779 266, the radial pressure should be transverse to the longitudinal seam - possibly varying unevenly be applied during heating and cooling, whereby it is smaller in the area of the inner edge than in the area the outer edge. The corresponding device provides that the conveyor belts under a pointed Angle to each other are adjustable, which is achieved by a rotary adjustment of the mandrel supported by a magnetic device is made possible.

Also result from this device

the above-mentioned problems with regard to the belt and the quality of the seam as well as with regard to today's claims completely inadequate feed speed, which is not significantly increased by the magnetic support of the mandrel could be. Magnetic support is complicated

and requires, among other things, that an HF induction welding device, for example, can only be used with great difficulty.

From DE-OS 28 49 239 a device is

for the production of a hose from an endless with at least one that can be softened by heat and connected to oneself Substance-coated non-ferrous metal foil web known whose Long edges are heat-sealed together. Here, the tube shape is between a round, non-ferrous Winding mandrel with a rod made of magnetizable material held in it and a high-frequency induction coil carried out in such a way that the tubular shape encases the mandrel and the axis of the sealing seam to be produced aligned with the axis of the rod. Here, the overlapping longitudinal edges are supposed to be carried by the known conveyor belts are compressed by melting plastic during sealing.

In the device, the induction coil wraps around the entire mandrel, which should consist of a non-ferrous metal. To strengthen the induction field in the area of the seam, a rod made of magnetizable material is arranged in alignment in the mandrel. This coil forcibly heats the metal foil in the entire pipe, even if a concentration is achieved in the seam area. As a result, on the one hand, an unnecessarily large amount of energy is wasted and, on the other hand, the transport conditions are worsened, since a heated, soft film body is more difficult to transport than a cool, stiff film body; In addition, the effort for cooling increases and the transport speed increases _< igkjej.t..wij: d. because of the longer cooling

time limited. A limited local pressurization of the Seam is not possible because of the provided bands.

The object of the invention is to improve a device of the type mentioned in that a pipe with a Any seam shape of consistently high quality in less time and at higher speed on a simpler one Device can be produced.

This object is achieved by a device with the features of claim 1. Due to the adjustable arrangement of the welding device it is possible to set the optimal distance between the gluing point and the rolling point. The cross adjustment is it is possible to optimally adjust the concentration center of the induction field with regard to the respective overlap width. The lateral arrangement of the conveyor belts simplifies the drive and the rollers of the downstream welding device Rolling pairs can act directly on the seam and thus a seam with optimal quality can be produced.

The measure of claim 8 on the one hand reduces the friction and on the other hand a possible sticking to the mandrel, if molten plastic phase escapes, prevents. Through the Measure according to claims 9 and 10, the length of the insert or the plate can be varied and thus to a moving adhesive point be adapted, so that a secure holding and guiding of the overlapping edges from the exit of the molded socket to shortly is guaranteed behind the adhesive point. By choosing the material of the insert or the plate according to claim 11, the Friction is reduced and the cooling is optimally passed on. The embodiments according to claims 12 to 16 are used Improvement of the quality of the seam in terms of its shape and rigidity (cooling).

The invention is explained in more detail below using an exemplary embodiment with reference to drawings. It shows:

1 shows the essential part of a device in accordance with the invention for the continuous production of deformable tubes from a laminate film strip in plan view in schematic representation,

2 shows a part of the device in side view with partial section, on an enlarged scale,

Fig. 3 shows a cross-sectional detail along III-III in Fig. 2 _#

4 shows a section according to IV-IV in FIG. 2 on an enlarged scale and

5 shows a counter roll with a different profile shape.

The device according to the invention contains a roll of film a laminate foil tape, which for example consists of an inner metal foil layer and two outer layers made of a plastic consists. A known film of this type consists of an aluminum layer which is coated on both sides with polyethylene is.

If necessary, the foil tape is trimmed on both sides to avoid fluctuations in the width of the tape or damage of the edges, which could reduce the quality of the seam. Then the tape is funneled over an introduction (with insertion slot) of a molding device 1 for

Manufacture of a dimensionally stable tube 2 (Fig. 1,2) with it overlapping edges 3, 3 '(Fig. 3,4) supplied. The specific shape of these parts is known; they are therefore not shown. The molding device 1 consists of a molding sleeve 4 (the output end of which is indicated in FIGS. 1 and 2) and a molding mandrel The mandrel 5 consists of any material with good thermal conductivity, e.g. steel, which is preferred because of its rigidity will. The mandrel 5 has channels 6 (Fig. 3) for the passage of a coolant such as water. At the exit end of the molded socket is above the overlap area of the edges 3 of the film strip is a preferably rectangular short, extending along the The cooled HF coil 7 extending parallel to the tube axis and thus also to the overlap area and can be adjusted transversely thereto

arranges,
e ^ Through the RF coil 7, an induction field should be higher

Density can be guaranteed. The RF coil 7 has an exchangeable one Plate 8 made of a good heat-conducting, an electrical non-conductor representing material of high hardness and a low coefficient of friction. The plate 8 lies in this way on the overlapping area of the molded sleeve 4 exiting pipe 2 on that the area is guided and held together. The side emerging from the socket 4 is Tube 2 grasped on both sides by endless conveyor belts 9, each around a driven and a driven guide roller 10 circulate.

At a distance from the RF coil 7 is also in the overlap area the edges 3,3 'a pair of rollers, consisting of

-räwnr · »

• · β <

-11 -

an outer roller 11 acting externally on the area and a counter-roller 12 acting on the area from the inside. The outer roller 11 is driven and cooled with a device for regulating the roller pressure to be applied Mistake. The inner counter roll 12 is mounted in a thermally conductive manner in the cooled mandrel 5 and is cooled by this. The rollers 11, 12 can have a more or less planar shape have or also be profiled. In the embodiment according to FIG. 4, the outer roller 11 is cylindrical and the counter roller 12 provided with a trapezoidal recess 13. The counter roller 12 according to FIG. 5 has a wedge-shaped recess 14 on. Through the opening cross-section, which is formed by the profile of the rollers 11, 12, the shape of the The weld seam formed is determined, since the profile of the rollers 11, 12 can be selected as desired, and the shape of the seam is also arbitrary. The pair of rollers 11, 12 creates an ideal line contact and thus an optimal degree of deformation is guaranteed. As soon as it emerges from the molded socket 4, the mandrel 5 up to its free end in the upper part an axial groove 15 with a width that is slightly larger than the overlap area is wide.

From the beginning of the groove 15 in the area of the exit of the molded socket the closed shape of the mandrel 5 is produced by an exchangeable insert 16 (see Fig. 3). The deposit 16 consists preferably made of a material with the same properties as the plate 8 of the RF coil 7. In the exit area the RF coil 7 becomes a step due to the lack of the insert 16

formed, ie the seam area can no longer be on the
Pin 5 rest on and there is no risk of sticking.
The step should be shortly after the adhesive point in the direction of movement
lie.

The device according to the invention works as follows. The pipe 2 formed and emerging from the molded socket 4 is laterally
detected by the conveyor belt 9 and from above through the plate 8 | the RF coil 7 and held from below by the mandrel 5 I

and led. An induction field becomes higher in the RF coil 7
Density creates that the metal layer in the foil stimulates and
warmed up. This heating spreads from the metal layers in the plastic layers between the metal foils
faster in the overlap area than in the respective; * ■

Outer layers with cooled elements, on the one hand the S

Plate 8, on the other hand the insert 16 of the mandrel 5 in contact It

stand. In the inner area it comes from the softening of the S.

Plastic to glue these layers together, there will be ||

the glue point is reached. With the same power of the HF coil 7 |

this adhesive point becomes un- $ with different film materials

reached different times. Shortly after the glue point

is reached, the support of the seam area should be supported by} |

the insert 16 stop. This is no longer necessary because äjj

on the one hand in the heated and softened film no tension ^

There are openings that can cause them to deform, ψ, and the given shape is retained by gluing. |

Because the mandrel then does not have a closed outline shape, the friction is also reduced. The glued overlap area comes on when moving further of the tube 2 between the cooled rollers 11, 12, where the seam receives its final shape and at the same time securely sealed will. Because the rollers 11, 12 are cooled, the seam is immediately given a solid shape and the tube 2 is given such rigidity, that further guidance through the mandrel 5 is unnecessary, which can thus end here just like the conveyor belts 9. The mandrel 5 can, however, also be provided with a shoulder which converts the tube into a flat shape before a cross section.

The rolling of the seam should preferably take place when the heat generated in the metal foil penetrates the plastic material Has heated the outer layers sufficiently to form a seam and seal. This point in time is defined as the ideal rolling point. The rolling point can be influenced somewhat by the level of the rolling pressure applied. The spatial distance of the The glue point from the rolling point changes with the structure of the film and with the speed of movement of the pipe through the Contraption. This makes it necessary to be able to adjust this distance. To this end, according to the exemplary embodiment the RF coil 7 is arranged adjustable in the direction of movement, the adjustment of the rollers is conceivable, but more complicated. To adapt to the distance between the RF coil 7 and the molded sleeve, a longer plate 8 can be provided, which also has the Gap covered. According to the shift of the

The length of the insert 16 must also be adapted to the adhesive point. The greater the applied energy density, the easier it is to define the glue point and the lower it is the distance from the gluing point to the ideal rolling point. The speed of propagation of the generated heat in the plastic layers can be determined by thermocouples, so that the distance depends on the selected speed from glue point to roll point and thus from HF coil 7 and pair of rollers 11, 12 can be easily determined. The drives of the conveyor belts 9 and the driven roller 11 are synchronized. The pipe 2 is not heated anywhere except in the seam area and there only from the inside; on the contrary, the pipe 2 is even heated cooled by the mandrel 5 and the coil 7 from the outside. The mandrel 5 can be made of metal, since it is on the one hand through the metal layer of the laminate is largely shielded and also intensively cooled. The mandrel 5 can thus be made of steel and since it can also be kept very short, no additional support devices are required. The lateral attack of the conveyor belts 9 in the cooled area of the tube 2 means that critical conveyor belts are unnecessary heated seam area. By adjusting the RF coil transversely, it is possible to adjust the concentration center of the induction field to optimally adapt to the respective width of the overlap of the edges.

Claims (10)

PATENTANWÄLTE ZELLENTlN ZWEIBRÜCKENSTR. 16 £ 3OOO MUNICH 2 Automation Industrielle SA 12 February 1981 Route de Savoie a ± v 81038 1896 Vouvry / Switzerland RZ / for protection claims 1. Apparatus for the continuous production of endless deformable tubes from a laminate foil strip with a metallic inner layer and at least one outer layer made of a plastic by molding a tube with overlapping edges, holding together and welding the overlapping edges by generating heat in the metallic inner layer by means of a High-frequency or ultrasonic welding device for softening the plastic and sealing the seam and its subsequent cooling, the tube being transported by driven belts, containing a feed device for the laminate film strip in a molding device consisting of a socket and a dome with a closed contour, a high-frequency or ultrasound ^ welding device ⁱⁿ the region of the shaping mandrel continues and is cooled, a cooling device and driven feed belts, characterized in that the welding device (7) in moving direction of the Pollenba ndes and crosswise to it is arranged adjustably so that the welding device (7) is followed by a pair of rollers (11, 12) is that the overlap area of the edges (3, 3 ') of the tube (2) formed between the outer roller (11) and the inner counter roll (12) of the pair of rolls is roll formed, and that the conveyor belt (9) the tube (2) Grasp both sides outside the seam area. 2. Apparatus according to claim 1, characterized in that the mandrel (5) in its upper surface, starting in the end region of the welding device (7), one up to has the free end of the mandrel (5) extending gradation in the form of an axial groove (15). 3.Vorrichtung according to claim 2, characterized in that the groove (15) is continued into the exit area of the molded sleeve (4) and in the continued area a die Has full shape restoring replaceable insert (16). 4.Vorrichtung according to any one of claims 1 to 3, characterized in that that the welding device consists of a short rectangular cooled RF coil (7) for generating a j-induction field of high energy density, which in the direct Contact area with the overlapping edges (3, 3 ') of the tube (2) formed is an electrically non-conductive having exchangeable plate (8). - 3 - 5. Apparatus according to claim 3 or 4, characterized in that that the insert (16) and the plate (8) consists of a material that is a good conductor of heat, an electrical Dielectric, has a low coefficient of friction and high hardness. 5 _m device according to one of claims 1 to 5, characterized in that the outer roller (11) is driven and its roller pressure can be regulated. 7. Apparatus according to claim 6, characterized in that the drive of the conveyor belt (9) and the drive of the outer roller (11) are synchronized. S. Device according to one of claims 1 to 7 _t characterized in that the outer roller (11) is cooled and the inner mating roll (12) is thermally conductively connected with the cooled mandrel (5). 9. Device according to one of claims 1 to 8 characterized in that at least one roller (11,12) has a profile. 10.Vorrichtung according to claim 9, characterized in that that the outer roller (11) is cylindrical and the inner counter roller (12) has a trapezoidal or wedge-shaped recess (13,14).