DE1479263A1 - Device for welding one or both ends of tube sections made of plastic material - Google Patents

Description

DIPL.-INQ. H. STEHMANN «Nuremberg a BS8ENWBINSTRAS8B 4-4 DIPL.-PHYS. DR. K. 3CH WEINZER τη .: office0911.203727 private: 77 «»

TELEGRAM ADDRESS: STANDING PATENT PATENT ANWALTS

BANK ACCOUNTS:

DEUTSCHE BANK AG. NORNBEtGNS. MIIM POSTAL CHECK ACCOUNT: NORNBERG <7M1

U79263

P 14 79 263.3 Nuremberg, 1.7.68 19/47

Mr. Karl-Heinz Honsei, Bielefeld, Herford Str. 285

"Device for welding one or both ends of tube sections made of plastic material" m

The invention relates to a device for welding one or both ends of tube sections made of plastic material using a rotating drum that feeds the individual hose sections separately from one another and on the circumference of which there are several welding stations.

There is largely an endeavor to make bags and sacks, predominantly Kreuzboden- or Kreuzbodenventilsäoke, as they have been up to now single or multiple layers of paper were made under

J ₀ use plastic material to fabricate. If the same

«O Plastic bags or plastic sacks currently still in proportion co

e *> are on the market to a small extent, this is due to the fact that the

^ Processing of plastic material for the present purposes still

, “Not sufficiently economical or not with sufficient certainty m

is feasible from riohend tight welds.

\ 'OUe documents (Art. 7, Paragraph 1, Paragraph 2, No. I, Clause 3 of the Amendment Act of 4. £

909831/1006

The welding of one or both ends of a section of plastic tubing was previously carried out in such a way that the workpiece is welded at a standstill, i.e. the Welding machines used for this purpose worked discontinuously, taking into account that the welding time was Formation of a weld seam is relatively long, especially when processing thick-walled films. It is obvious that the use of such discontinuous welding machines compared to the high-performance, continuously operating machines used in the manufacture of bags and Saoken made of paper is uneconomical.

In recognition of these circumstances, it has already been proposed to use plastic films for the production of bags or sacks in continuous Rotary welding process using a rotating drum with several welding stations on its circumference are arranged. A plastic hose is continuously fed to such a welding drum. It can with this only transverse welds are carried out by means of the welding bars lying parallel to the drum axis, and only below Use of the impulse welding process. In order to make longer welding times possible, there are between adjacent sealing bars inwardly directed bulges are provided, into which the plastic tube web by means of an additional Impact device inserted and in this position on the base of the chamber depressions by suction air should be held. The plastic bags to be produced are made in the longitudinal direction of the plastic web on the drum, the plastic sheet is opened at the intended distance

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the drum with cross welds. Sa the length Such a sack is generally always larger than its width, in order to comply with the required Welding time a drum with a particularly large Durohmeseer required. Only after going through the entire scope The drum is used to separate the individual workpieces from the plastic sheet. During this cycle the Plastic sheet with its cross-weld seams under one pointed Tension that makes it impossible to create so-called sump welds power. Due to the way the additional wrapping device works, displacements can occur in the longitudinal direction of the Schlauohbahn, which make it impossible it can be that the section of the individual workpieces is carried out properly next to each weld seam after the drum circulation. This can result in rejects to a greater extent. Such a welding machine is especially durable on one movable sealing bars arranged around the rotating chain.

The invention is based on the object of creating a device which allows a continuous and thus economical production of plastic bags or sacks, but which largely avoids the shortcomings of the continuously operating welding machine described above will. With the device, all types of soot-

_ω seams can be produced and high performance can be achieved.

The invention is accordingly characterized by one of Existing lower and upper band arrangement, calibrated around the entire

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The circumference of the revolving drum is placed on the holding device, which shows the welding position of the transverse and spaced apart supplied hose sections secures and that two welding elements a welding station together with a control device for the movable welding element on the jacket or are arranged on an end face of the welding drum, wherein the control element for the movable welding element from a by a solenoid valve controlled pneumatically or hydraulically operating cylinder piston arrangement consists.

Due to the transverse position of the sole tube sections on the jacket surface of the welding drum, a larger number of tube sections can be used be accommodated on the drum shell. This means that a longer welding time is available due to this feature. Since each hose section is independent in and of itself without connection with the neighboring hose sections sioh is on the drum circumference during the welding process, Any type of welding can also be carried out, e.g. also a tail weld, which is often compared to the impulse weld ensures a closer weld seam. Duroh the relatively many welding stations on the circumference of the welding drum it is naturally possible to achieve long welding times with high output.

Duroh the feed of the individual hose sections separately from each other, namely in a transverse position to the welding drum, the prerequisite is also given that the transverse smart

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cut a one that encompasses this end at its end to be welded Plastic hoops folded in a V or U shape in cross-section before this hose section reaches its welding station. Thereby it is without additional time wall possible that the hose section is provided with a so-called lap seam on one or both of them. You can be here proceed in such a way that the transversely conveyed tube sections of the plastic strips run endlessly and that only immediately before storing the tube sections of the plastic strips is severed at the longitudinal edges of the hose sections. The device according to the invention has for the plastic strip a supply roll, a fixed Palzeinriohtung and a cutting device. The controls for the Movable welding elements can also be provided on an additional carrier disk rotating with the welding drum.

This basic structure of the welding machine according to the invention It also allows that on the outer surface of the welding drum in addition to the welding elements in the circumferential direction of the drum in a manner known per se Welding elements are arranged parallel to the drum axis. In the Transverse position of the hose sections according to the invention on the outer surface of the rotating drum, it is evident that the welding elements for the cross welds at the ends of the J £ hose sections must be designed in the shape of a circular arc. if

_ »Now to these arc-shaped welding elements, - »who have to weld the ends of the hose section, too α

Yyy there is still the possibility of attaching additional welding elements, which are arranged parallel to the drum axis, then

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Only then does the prerequisite arise that not only such bags or sacks are produced on this machine can, so the transverse welds at their ends have a Pillow format when the sack is filled, it is this interaction of transverse and longitudinal welds on the outer surface the rotating drum creates the possibility of creating such bottom closures, as is the case with cross bottoms, block bottoms or the like are known per se.

The invention also provides that the movable welding element is not designed as an active welding element. The inactive welding element then only serves as a pressure beam when performing the weld. Such an arrangement has proven to be particularly advantageous, depending on whether the wall thickness of the foils to be welded is relatively thin, or if the wall thickness of the foils to be joined represents an unequal wall thickness.

The drawing shows an exemplary embodiment of the subject matter of the invention and shows:

Fig. 1 is a schematic front view of the welding device Way presented,

Fig. 2 is a partial section through the welding drum, ^ Fig. 3 a welded sack with a lap seam, ^ Fig. 4 is a Längsschnityäurch the bag gem. Fig. 3, ο Fig. 5 a welded sack with a shrink or

^m impulse seam,

6 shows a longitudinal section through the sack according to FIG. 5,

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Pig. 7 and 8 circuit diagrams for switching the control elements of the sealing bars

The workpiece 1 is from the left of the welding machine to Pig. 1 supplied, it consists of a plastic hose section that is fed transversely to the rollers 2 and 3. The drum upper belt 4 runs around the drum 3, and a lower belt £ around the roller 2, which is returned via the roller 6. A lower drum belt 7 runs around the welding drum itself is diverted via rollers 6 and θ. Through the tape transeport between the belts 4 and 5, the workpiece is transferred via the deflecting roller 9 to the working cylinder 10 of the welding drum The working cylinder 10 has eight work stations, which are provided with the numbers I to VIII. From these workstations I to VIII is only work station I in Pig. 1 shown.

On the working cylinder 10 is the Sohweißbalkträger 11 with the insulated head pieces 12 and 13 rersohraubt. A welding beam carrier 14 presses on this welding beam carrier 11 Welding beam support 14 is attached to levers 15 and 16. These levers are screwed onto the shaft 17, which in turn is in the Bearing blocks 18 and 19 are mounted. On the shaft 17 a ο lever 20 is attached, which via an eye rod 21 with the Sohub- The piston 22 of a jereßluftzylinders 23 is connected · The Prefi-ί air cylinder 23 is on the end face of the welding drum - »Working cylinder 10 screwed. The working cylinder carries ο also an electro-magnetic a compressed air valve 24 and the η

Welding transformer 25 for the welding bands of the welding bars.

-8th-

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The control during the welding process and the actuation of the Valves will be explained further below.

After the welding has taken place, the workpiece is passed through the diverter cylinder 26 removed. The workpiece is then guided by the two belts 4 and 28 to the depository. The sputum roll 29.30 bring the workpiece to the deposit belt 31

If the workpiece, i.e. the transversely fed plastic hose, is removed provided with a lap seam, as shown in! ig. 3 and 4, an additional one is fed in Film strip 32 with the help of the roller 33, the diverting roller 34 and the loop 35. This loop 35 is attached firmly and serves to fold the additional film strip into a folded strip, which can be U- or V-shaped in cross-section like.

After the welding process has been carried out, the protruding parts of the Strip with the help of the fixed knife 36 and the rotating Knife 37, 38 cut off, the weld seams themselves are each designated by number 39. The supply of compressed air

takes place through the hollow shaft 40 with the help of an automatic to

ο Cloth sleeve, which is labeled 41. On this wave 40 <o

<»The slip rings 42 for the supply of the ^ * electrical current and the control segments 43 for the cam _o switch 44 are arranged at the same time.

The control of the sole welding process for the production of shrink

sewing is carried out as follows:

Each work station I to VIII is a control segment 43 assigned to the shaft 40. The control segments 43 operate cam switches 44 (see Pig. 8). When closing a Switch 44 pulls in an auxiliary contactor 49 and thus switches on the solenoid valve 24 for actuating the welding bar support 14. As a result, the working cylinder 23 is actuated, after which the Lever 21 and 20 of the welding bar support 14 presses the workpiece against the welding bar support 11. On wave 40 is still at least one control segment 47 is arranged to operate a cam switch 45 · If the cam switch 45 is closed » an electronic timing relay 50 then receives a pulse. This closes the circuit to the transformer 25. This transformer ο maintains its voltage on the primary side via the slip rings 42 and emits its tension on the secondary side to the sweat band 53 (FIG. 7). After the preselected time on the time relay 50 has elapsed, the contactor 48 is switched off, the transformer is thus de-energized and the heating-up time of the sweatband is finished. At the same time, the auxiliary contactor 49 drops, whereby the solenoid valve 24 in the initial division goes back and actuates the working cylinder 23 in the opposite direction. As a result, the Sohweißbalkentrager 14 is again from Workpiece lifted

CD
CD
(O

⁰⁰ If an impulse seam is to be made, an optional

^ sohalter 46 brewed to the switch position I. Duron this oSwitching division, the solenoid valve 24 is no longer dependent on

ojkeit controlled by the timing relay 50, but the controller is now taken over by control segment 43.

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Since the circuit described at deijbuvor the welding beam support 14 presses on the workpiece longer than the actual welding time, the weld seam has time to cool down before the Pressure of the sealing bar 14 ceases.

Due to the arrangement of eight work stations on the drum, the switching time of the timer relay 50 would normally have to be dimensioned smaller than it corresponds to the angular time of approx. 45 °. In order to extend the To be able to carry out welding time, according to a further development of the invention, two control segments 47 for actuating limit switches 45 provided. The cams of the control segments 47 are angularly offset from one another in such a way that the one segment base the welding process for work stations I, III, V, VII and the other control element disk the even-numbered ones Workstations operated. This makes it possible to reduce the welding time of a work station up to an angular time of approximately 90 ° ausudeüfen. Over a certain angular range there are then two successive workstations switched on at the same time.

- Claims 909831/1086

Claims (8)

Claims (1. ) Device for welding one or both ends of hose sections made of plastic material using a rotating drum, to which individual hose sections are fed separately from one another and on the circumference of which there are several welding stations, characterized by one of sub (5,7) and Upper belt arrangement (4), which is arranged around the entire circumference of the rotating drum (10) and which secures the welding position of the hose sections that are fed in transversely and at a distance from one another and that each two welding elements (11, 14) of a welding station (I - VIII) are arranged together with a control device for the movable welding element (14) on the jacket or on an end face of the welding drum (10), the control element for the movable welding element (14) being pneumatically or hydraulically controlled by a solenoid valve (24) working cylinder piston assembly (23). 2. Device according to claim 1, characterized by a supply roll, a fixed folding device (35) and a cutting device (36,37,38) for an endlessly fed plastic strip (32). 3 · Device according to claim 1, characterized in that the control elements (23, 24, 25) for the movable welding elements (14) on an additional rotating with the welding drum (10) -to »U *** 909831/1086 U79263 ηκ Carrier disk are provided. 4. Device according to claims 1 to 3, characterized in that on the Ma ^: eleven pools of the welding drum (10), except for the welding elements (11,14) in the circumferential direction of the drum, in a known manner additional welding elements parallel to Drum axis (40) are arranged. 5. Device according to claims 1 to 4, characterized in that only the immovable welding element (11) is designed as an active Sohweißelement. 6. Device according to claims 1 to 5, characterized in that on the welding drum shaft (40) the individual welding stations (I - VIII) associated control segments (43) and cam switches (44) for actuating a solenoid valve (24) are provided (Fig. 8th)· 7. Device according to Claim 1 or the following, in particular Claim 6, characterized by control segments (47) and JSncb switch (45) for switching on a preferably adjustable time relay (50). 8. Apparatus according to claim 6 or 7, characterized in that two control units, each consisting of a control segment (47) and a timer (45) are provided, which alternately every second welding station (I, III, ... or II "IV, ...) is assigned. 9 · Device according to claims 6 to 8, characterized by umeo holding means (46) for butt trunk or impulse seam welding · 909831/1086