DE973238C - Method and device for dismantling a liquid-filled container made of thermoplastic material - Google Patents

Description

ISSUED DECEMBER 31, 1959

A 20905XII j 8i a

Frankfurt / M.

The methods and devices are numerous. known to be liquids, or flowable ointments fine powder in a tube made of a thermoplastic material in the way pack that of the tube closed at the bottom, containing the filling material by applying Cross-weld seams can be divided into individual containers and later separated. The weld will either with welding tools heated by resistance wires or with the help of high-frequency electrodes executed. It is known that the heated with the help of resistance wires Welding tools can be kept energized at all times, while the peculiarity of high frequency heating requires that the welding tool may only be subjected to a current surge for a few seconds.

When cross-welding a plastic hose filled with liquid, the hose, which is cylindrical or at least elliptical under the hydrostatic pressure of the product Assumes cross-section, in the intended welding zone, first graze together until the opposite walls of the hose and lie flat on top of each other in this zone. Thereby the product is turned off this press zone is displaced on both sides, and it is desirable that the displacement

909681/5

lent is complete, so that the hose walls are directly in the intended welding zone be brought into contact with each other without any parts of the filling material in between are located.

According to the working principle applied here, the known processes fall into two groups. One group works with separate tools for pressing and welding, whereby ίο a perpendicular to the hose axis movable welding tool, a plurality of separate and independent of the latter, more movable in the direction of the hose axis in front of and behind the welding tool arranged pressing tools and an abutment opposite these provided are and by pressing the pressing tools against the abutment initially on the hose a contiguous fluid-depleted zone is established. The other group uses a and so the same tools for pressing together and welding.

There are concerns about using the same tool for pressing and welding contrary, because in many cases this tool is also used as a back and forth movement Conveyor element is used to transport the pipe string by one package length after each welding operation, and both that It is advisable not to use a continuously or intermittently heated press like conveying and therefore heated organ should be run. But even if the pressing and welding tools does not simultaneously exercise a promotional function, this arrangement is disadvantageous because it the tension exerted on the walls of the pack by the internal pressure of the liquid filling itself affects into the welding point.

Furthermore, there is a device for dividing a filled plastic tube into individual containers known who works with a variety of pressing and welding tools, as a result of their chain-like arrangement are provided at the same time as organs for conveying the hose. Machines of this type have the disadvantage that as a result of. Variety of pressing and welding tools multiple disturbance possibilities are present "by, for example, the individual to the Chains moving pressing and welding tools do not face each other exactly, and that, in addition, the machine is only set to produce a single package size at a time, unless. a plurality of interchangeable Chains with different distances between the individual pressing and welding tools provided becomes, which is both cumbersome and cost-increasing.

In the devices that work with separate pressing and welding tools, are so far the working zones of the two tools in different areas of the hose, or that The welding tool must move the pressing tools on the hose towards both sides Push away in the direction of the hose axis. The latter either leads to severe mechanical stress and, if necessary, damage to the tubing material or permitted, if that Wants to protect hose material, only an imperfect displacement of the filling liquid from the Working area of the pressing and welding tools.

The invention relates to a method for perfecting the mode of operation when used separate tools for pressing and welding, as well as suitable devices for exercising this procedure.

In a method for dismantling a liquid-filled container made of plastic it is shaped an endless tube of any cross-sectional shape or a finite container formed from plastic film with or without welding in Single container closed on both sides or on all sides with the help of one only perpendicular to the hose axis movable welding tool, a plurality separately and independently of the welding tool more movable, arranged in the direction of the hose axis in front of and behind the welding tool Pressing tools and an abutment arranged opposite them, whereby by pressing the pressing tools to the abutment first on the hose a coherent fluid-emptied Zone is produced, the invention consists in leaving at least one the pressing tools by lifting off or rolling off at least one of the other pressing tools a part of the emptied zone on the hose while maintaining its emptying state is released for the engagement of the welding tool to be lowered. By doing this Press tool to release the zone in which the weld seam is to be created, only from Hose lifted off or unrolled on it, but not shifted on it, is a complete one Protection of the hose material guaranteed during the pressing operation.

The advantage of the new process lies in its high operational reliability, which results from the fact that the filling material without the aid of the welding electrodes and without mechanical abuse of the plastic hose in the area of the welding zones is removed and that no tensile stressed wall parts of a strength-reducing Ef warming get abandoned.

The process principle described can not only be applied to liquid-filled containers in the form an endless tube of any shape, but also made of plastic film with or without welding formed finite containers apply that by way of welding to be broken down into smaller individual containers of any shape and shape. In this In this case, each individual container is bounded by a single weld seam running back into itself and locked.

. Various devices can be used to carry out the procedure Design are applied, some embodiments of which are described below will.

In one embodiment, the operation of compressing and deflating the plastic tube Transferred to a pressing unit at the pressing point, which consists of one with two pressing surfaces equipped first and one engaging between these two pressing surfaces, separately movable second press tool consists. Both pressing tools expediently form a closed one Pressing surface. The second press tool

ίο is retractable on its own while a Welding tool, the working area of which is equal to or smaller than that of the said pressing tool can, can be moved into the same job on the hose. The second press tool is included assigned the task of making the plastic hose free of liquid immediately in the zone, in which the weld seam is then to be placed. This second pressing tool is expedient in the first phase of movement, if

ao both pressing tools together on the liquid-filled Hose are brought up, a certain lead over the first pressing tool granted, so that first the second additional and only very shortly afterwards the first or Main pressing tool touches the plastic hose and compresses it. This causes the Hose through first in the relatively narrow contact zone of the second press tool Lateral displacement of the product liquid-free

■ 30 is made, and then with the setting up of the first or main pressing tool this liquid-free zone of the hose in the longitudinal direction the same is widened. The work surfaces of the two pressing tools can also

.35 lie in a common plane without leading one.

An example of such a device is shown in Fig. 1. A made of molding compound, plastic, Ceramic, hard rubber or the like. Manufactured first or main pressing tool in the form of a a narrow side standing right-edged, possibly downwardly tapered component 1 has one over its entire 'length and the entire working width extending chamber 2, in which the welding tool 3 is arranged, which is designed as a high-frequency electrode and for itself is set up independently displaceable in the vertical direction. Either serves as a counter bearing 4 a mirror image of the same unit or a simple block or table made of electrically conductive Material used as a mass or earth for the high-frequency electrode serving as a welding tool works. 5 and 5 'is the tube filled with liquid, with 5 being the already closed lower one End of hose, d. H. the last divided single pack, 5 'the upper, still open part of the Represents hose. In component 1 there is another one that extends over its entire working width narrow chamber 6 is provided, which in

<6ü runs at an angle to chamber 2 and into the lower end thereof opens in such a way that both. Chambers have a common lower opening. In this chamber 6, the second pressing tool 7 is arranged, which is made of any material, such as plastic, wood, metal, ceramic or elastic rubber.

In a preferred embodiment, this second pressing tool 7 is in the direction of the central plane the chamber 6 is set up to be elastically resilient. The suspension is by the spring 8, which is on the axle 18 works, done. The spring is omitted if the tool 7 consists of an inherently elastically yielding Material, such as rubber, is made. The extent of the suspension is measured so that the second pressing tool 7, as long as no pressure is exerted on its underside, with its lower Narrow edge around a very small piece over the lower narrow side of the main press tool acting component 1 protrudes downwards. This ensures that when the Unit against the plastic hose the ■ small pressing tool 7 initially only on the filled Hose presses and this in one of the narrow edge of the pressing tool 7 corresponding Makes width fluid-free. With the further movement of the unit against the hose occurs then also the underside of the main pressing tool ι with the hose in contact and widened the pressing and emptying zone to the right and left, while at the same time from Material resistance of the hose the resilient second pressing tool 7 with its lower edge up is pushed back in the height of the lower edge of the main pressing tool ι.

Then the second pressing tool 7 is pulled up so far that the common lower opening of the chambers 2 and 6 is free, whereupon the welding tool 3 downwards to contact with the compressed and the drained hose in the nip is drawn down around the transverse weld seam in the nip of the hose 'to produce. When the welding tool as a high frequency electrode is formed, it is expedient in a manner known per se by a corresponding Switching device energized at the moment of reaching its lowest level and switched off again after the time required to produce the weld seam and returned to the top. If the welding tool is used in a different way, e.g. B. with the help of built-in Resistance wires, heated, so this exact dimensioning of the power supply is unnecessary.

Since the welding tool has no pressing work to do, it needs to move downwards just to be placed on the flat plastic tube with the pressure that is required is to allow the two plastic layers to flow together on their insides in the weld line bring to. The pressure is sufficient, for example with high-frequency welding from plastic films to handbag goods is common.

The alternating upward and downward movement of the second pressing tool 7 and 'is advantageous. of the welding tool 3 made via a common 1 * 5 drive shaft, the z. B. in space

can be arranged between the two tools and parallel to their main planes. For example, on a main shaft 18 one or more gears 9 are mounted, which mesh simultaneously with one or more gear racks 10 and 11 which sindr mounted on the facing surfaces of the one part of the second pressing tool 7, on the other hand, the welding tool 3 ¹ just as easily can Movements are effected by levers mounted on the shaft 18.

In a further embodiment of the device, the unit described is in a vertical position Mounted holder 12, through the intermediary of which it is by means of a suitable drive device up and down at the desired working rhythm and thus against the counter bearing 4 is moved.

In the in

Fig. Ι embodiment shown, the holder 12 has the shape of a right edge, which with the longitudinal walls 13, 14 extends downwards into a rectangular space that is open at the bottom. In these The space is made up of the first or main pressing tool i, the second pressing tool 7 and the welding tool 3 and the additional facilities described above existing unit inserted and mounted on the inner strips 15, 16 provided on the lower edges of the walls 13, 14. The unit is against the pressure body of the holder 12 in the vertical direction by two or several springs 17 cushioned.

Figs. 2 and 3 show two further exemplary embodiments.

In Fig. 2, the first or main pressing tool consists of a ruler-like body 1; the second Press tool 7 has the shape of a rubber or metal roller, while the welding tool 3 in the has essentially the same shape as in the embodiment of FIG. The main press tool ι is performed on the body 27, which it includes with its upper part. On the cover plate 19 of the body 27 acts vertically from above a drive member, not shown, which the body 27 pushes downwards. The welding tool 3 is vertically displaceable in such a way on the one Arranged longitudinal wall of the main pressing tool that the cover plate 19 of the body 27 at their Downward movement also moves the welding tool 3 downward. The welding tool can be arranged in a vertical continuous chamber of the Hauptpreßweckzeuges 1, similar as in the embodiment of Fig. 1, or it is by means of bolts 20, 20 on the vertical wall of the main pressing tool 1 attached and opposite this in guide slots moved through which the screw boltsea passed are. The welding tool 3 is expediently firmly connected to the cover plate 19. One exact guidance of the welding tool 3 is ensured by guide rails 21. Of the Body 27 and the main pressing tool 1 are cushioned against one another by spiral springs 22.

The second press tool has the shape of a cylinder sector 7 forming a press head Rubber or other suitable material, the longitudinal axis of which is transverse to the axis of the plastic tube runs. The pressing tool 7 is rotatable in its longitudinal axis at the lower end of a Lever or pair of levers 23 articulated, the mediation of a torsion bar 24 in the lower Half of the first or main pressing tool 1 is mounted.

In the lower half of the welding tool 3 is on ,, the one facing the main pressing tool Surface firmly connected to a pressure piece 25, which in the upper position of the welding tool 3 on the highest point of the torsion bar 24 rests. The device described works like that Device according to Fig. 1 against the working surface of a counter bearing 4. Between the two is the liquid-filled hose 5, 5 'preferably carried out horizontally. 5 'represents the lower end a liquid-filled plastic tube of any length, while 5 is one of the already illustrated by cross-welding individual packs. By in the direction of the arrow If the unit described above is brought down, the ruler-like tapering occurs first lower edge of the main pressing tool 1 with the hose in contact and presses this between itself and the working surface of the counter bearing 4 flat together, with the one in the hose at the point of contact contained filling liquid around the width of the lower edge of the main press tool ι is displaced in the direction of the filled tube 5 '.

In Fig. 2 the unit described above is shown in the position in which the first or main pressing tool 1 has just compressed the hose between itself and the counter bearing 4 with its lowermost edge. The pressure acting in the direction of the arrow on the cover plate 19 is now continued, as a result of which the body 27 is pushed downwards into the upper cavity of the main pressing tool while the spiral springs 22 are compressed. At the same time, the pressure plate 19 guides the welding tool 3 vertically downwards in the direction of the hose. Through the mediation of the pressure piece 25, the 'torsion bar 24 is pressed downwards in its guide 26'. Under the action of this pressure, the lever 23 carrying the rubber roller 7 at its lower end deviates by twisting the rod 24 in such a way that its lower ^U 5 end shifts to the right, with the rubber roller 7 compressing another length of hose and displacing the Amount of liquid contained therein on the resting on the counter bearing 4. Hose section 5 'rolls off. ia ° By this movement, a relatively wide tube portion of liquid is emptied, and also the path for the so far released after downwardly moving welding tool 3 that this is lowering to the liquid-depleted zone 5 ^ia of the compressed hose

and after it has been energized, make the transverse weld in this zone can. As soon as the weld seam is completed, the pressure acting in the direction of the arrow is released and the whole assembly goes to its uppermost position with the re-expansion of the spiral spring 22 Starting position back. The described rolling of the second press tool 7 on the Hose has an exhaustive effect, especially when this tool is made of elastic rubber lateral displacement of the product contained in the hose with absolute protection of the Hose material that does not experience any stretching.

Fig. 3 shows a variant of the device described last. Here, too, the first or main pressing tool and the welding tool 3 are telescopically pushed into one another so as to be displaceable with respect to one another and so 22 are cushioned ^{against one another by means of the spiral spring.} The second press tool 7 is rotatably mounted about a shaft 32, which in turn is arranged on the lower arm of a double-armed lever 28, which in turn is rotatably mounted about a shaft 29 which is carried by a Lageras bock 30 which is attached to the one longitudinal wall 'des Welding tool 3 is attached. A tension spring 31, which is fixed on the upper end of the lever arm 28 and on the upper part of the welding tool 3, pulls the lever 28 against one wall of the welding tool 3 in the rest position.

In Fig. 3a the device is drawn in the position in which the lower edge of the main pressing tool ι just pressed the liquid-filled hose against the counter bearing 4 and compressed has, while the second pressing tool 7 is just starting with the beginning piece of the hose section 5 'is in contact.

If you continue to apply the vertical pressure acting in the direction of the arrow, the Main pressing tool 1 and the welding tool 3 with compression of the spring 22 telescopically into each other, at the same time also the double-armed Lever 28 shifted downwards. The lever arm 28 gives way under tension of the tension spring 31 to the right and rolls the second pressing tool 7 to the right on the hose piece 5 ' away. By this movement, the second pressing tool 7 also presses a greater width of the Hose piece 5 'liquid-free and also gives the way for the downward movement of the welding edge of the welding tool 3 to compressed hose free.

In the lowest position shown in Fig. 3c the welding edge of the welding tool 3 touches the previously from the main pressing tool 1 in the Cooperation with the second pressing tool 7 of the fluid emptied hose is now under. The current is switched on and creates the weld seam in the emptied zone.

Fig. 3 b shows the device of Fig. 3 a seen in a side view from the left.

When using high frequency electrodes As a welding tool, the work surface remains relatively cool. If necessary, can in a manner known per se by arranging additional not shown in the figures Cooling devices a further cooling with compressed air or water are provided, which the The working surface of the welding tool 3 continues to cool.

Of course, the device can also be implemented in other embodiments, without deviating from the principle of work and construction according to the invention.

Claims (12)

Patent claims: i. Method for disassembling a liquid-filled Plastic container in the form of an endless tube of any cross-sectional shape or a finite container made of plastic film with or without welding in a container that is closed on both sides or on all sides Individual container with the help of a movable only perpendicular to the Schlauohachse Welding tool, a plurality of separate and independent of the welding tool more movable, arranged in the direction of the hose axis in front of and behind the welding tool Pressing tools and an abutment arranged opposite them, whereby the pressing tools are pressed against the abutment First a coherent liquid-emptied zone was created on the hose is, characterized in that leaving at least one of the pressing tools by lifting or rolling off at least one of the other pressing tools the Sahlauch part of the drained Releases zone for the intervention of the welding tool. 2. Apparatus for performing the method according to claim 1, characterized by a Pressing unit cooperating with a counter bearing, consisting of one with two First equipped with pressing surfaces and one engaging between these two pressing surfaces, separately movable second pressing tool, both tools together forming a closed pressing surface and the second Press tool is retractable, while a Sehweißwerkzeug, whose working surface is the same or smaller than that of the said pressing tool, in the same job is retractable on the hose. 3. Apparatus for performing the method according to claim 1, characterized by a Press unit with a press tool, the press head of which with its axis perpendicular is formed to the sole arranged, consisting of elastic material cylinder sector. 4. Apparatus according to claim 2 or 3, characterized in that the already closed Closest to the end of the hose 909 681/5 The pressing surface in the direction of the hose axis is narrower than the welding surface. 5. Apparatus according to claim 2 or 4, characterized in that within the first Press tool one over the whole Working width extending vertically, on the underside open chamber to Recording of the independently movable welding. tools «is provided and that in a further, also extending over the entire working width and into the lower end of the first chamber opening chamber the second independently movable pressing tool Made of metal, ceramic, plastic, elastic rubber or the like. Is arranged 6. Apparatus according to claim 5, characterized in that that the welding tool and the second pressing tool alternately, preferably via a common drive shaft, in such a way are movable that alternately the second pressing tool and the welding tool for guided lower opening of their chamber and brought into contact with the hose wall will. 7. Apparatus according to claim 6, characterized in that the second pressing tool and the welding tool on their facing sides with one or more racks are equipped, in which one or more arranged on the common drive shaft Meshing gears. 8. Apparatus according to claim 6 or 7, characterized in that the elastic Rubber existing second pressing tool is designed in its dimensions so that it is in its lowest position with its lower edge resilient slightly above the lower edge of the first Pressing tool protrudes. 9. Apparatus according to claim 2 to 8, characterized in that the power supply so set for the welding tool in a manner known per se via a contactor is that the welding tool only at the moment of touching down on the drained Hose zone electrified and after a to produce a durable. Weld is switched off again for a sufficient period of time. 10. Apparatus according to claim 2 to 9, characterized in that from the first and the second press tool and the welding tool existing overall unit is resiliently mounted in a holder which is of a suitable movement device in the respectively desired work rhythm on the Counter bearing is moved to and away from this again. 11. The device according to claim 3, characterized characterized in that the welding tool and the first pressing tool telescopically below mutual cushioning are nested and that the second press tool either on the first pressing tool or on the welding tool via levers in such a way that it can rotate and so coupled with the downward movement of the welding tool that it is through its Downward movement on the liquid-filled hose, releasing the work zone for the welding tool is rolled off. 12. The device according to claim 2 to 11, characterized by a known per se, operated with compressed air or water cooling device for the pressing tools and, if necessary, for the counter bearing. Considered publications: "Kunststoffe" magazine, year 1946, vol. 36, p. 8/9; British Patent Nos. 570451, 599 174; U.S. Patent Nos. 2,113,658, 2142505, 2166643, 2200971, 2294215, 2387812, 2441940; French patent specification No. 1 034 838. 1 sheet of drawings © 509578/305 10.55 (909681/5 12.59)