DE102021005940A1 - Method of making a fastener tape - Google Patents

Abstract

Method for producing a fastening strap which has a hooking part with which sections of the fastening strap can be connected to form a loop, for which the hooking part has at least one penetration slot which is provided with a latching device which interacts with at least one assignable latching part (28) of the fastening strap, as soon as the free end of the band passes through the slit, characterized by the following process steps- extruding a plastic material and at least partially introducing it into mold cavities (24) of a rotating mold roller (14) to form locking parts (28) arranged above on a carrier part (20) ,- demoulding of the latching parts (28) from the mold cavities (24) while at the same time pulling the carrier part (20) off the mold roller (14),- separating individual fastening straps from the carrier part (20), and- introducing the respective reach-through slot together with the latching device.

Description

The invention relates to a method for producing a fastening strap which has a hooking part with which sections of the fastening strap can be connected to form a loop, for which the hooking part has at least one penetration slot which is provided with a latching device which interacts with at least one assignable latching part of the fastening strap , as soon as the free end of the strap reaches through the slot.

Through EP 3 038 944 B1 a so-called cable tie is known, with a fastening strap that has a housing-like head part with which sections of the strap can be connected to form a cable tie loop for the purpose of enclosing components of any type, for which the head part has a reach-through slot that is provided with a latching device that is equipped with an assignable locking part of the fastening strap cooperates when the free end of the strap passes through the slot. To produce such a cable tie, plastic materials such as polyamide 6.6 or polyurethane are used, which result in the cable tie in the injection molding process. For this purpose, the raw material in the form of plastic granules is regularly heated to a specified temperature and liquefied and then pressed into an injection mold at high pressure, with around 50 cable ties being able to be produced in one operation. Since PA 6.6 is a hygroscopic plastic, it loses water content during the manufacturing process, so that some liquid is always added to the sales packaging of a cable tie, which is then completely absorbed by the cable tie over time as long as it is in the packaging .

Furthermore, is through DE 196 51 835 A1 a quick fastener in the manner of a band-shaped touch-and-close fastener part is known, which has individual hooking means on a carrier part and at the same time elements for engaging and hooking with the hooking means. In this case, loop-shaped elements under/or hook-shaped elements are used as elements for engaging and hooking. It is thus possible with the known solution to produce a removable adhesive fastener solely from this one adhesive fastener part, also in the form of a continuous product. Such an adhesive fastener can be used as a quick fastener in the field of medicine, e.g. orthopaedics, intensive care medicine and emergency care, for which the ends of the band-shaped adhesive fastener are guided through an eyelet and hooked around the eyelet with the part of the adhesive fastener that is not guided through the eyelet folded over, similar to the function of a cable tie, forming a loop around it.

Proceeding from this state of the art, the invention is based on the object of providing a method for producing a fastening tape in order to obtain large quantities of quick fasteners, such as cable ties, in this way in a cost-effective manner. A pertinent task is solved by a method with the features of patent claim 1 in its entirety.

• - Extrudieren eines Kunststoffmaterials und zumindest teilweises Einbringen desselben in Formhohlräume einer umlaufenden Formwalze unter Bildung von auf einem Trägerteil vorstehend angeordneten Rastteilen,
• - Entformen der Rastteile aus den Formhohlräumen unter gleichzeitigem Abziehen des Trägerteils von der Formwalze,
• - Abtrennen einzelner Befestigungsbänder aus dem Trägerteil, und
• - Einbringen des jeweiligen Durchgriffsschlitzes nebst Rasteinrichtung

durchgeführt werden, kann unter Einsatz der umlaufenden Formwalze mit ihren Formhohlräumen ein sogenanntes Chillroll-Verfahren durchgeführt werden, bei dem zunächst eine (Verbund-)Folie mittels eines Extruders mit nachgeschalteter Breitschlitzdüse produziert und dabei das Folienmaterial gleichzeitig mit den jeweils benötigten Rastteilen versehen wird. Anschließend lässt sich dann im Rahmen eines üblichen Stanzverfahrens die gewünschte Befestigungsbandgeometrie aus dem derart hergestellten flächigen Folienmaterial erhalten und vorzugsweise kann dabei gleichzeitig der Durchgriffsschlitz in das Befestigungsband mittels Einstanzen in das jeweils ausgestanzte Befestigungsband eingebracht werden. Es besteht aber auch die Möglichkeit das Ausstanzen des Befestigungsbandes nebst dem Einstanzen des Durchgriffsschlitzes in getrennten Stationen durchzuführen.The fact that according to the characterizing part of claim 1, the following steps

• - Extruding a plastic material and at least partially introducing it into mold cavities of a revolving mold roller to form locking parts arranged above on a carrier part,
• - demolding the locking parts from the mold cavities while simultaneously removing the carrier part from the mold roller,
• - Detaching individual fastening straps from the carrier part, and
• - Introducing the respective reach-through slot together with the locking device

are carried out, a so-called chill-roll process can be carried out using the rotating forming roller with its mold cavities, in which a (composite) film is first produced using an extruder with a downstream slot die and the film material is simultaneously provided with the required locking parts. The desired fastening strap geometry can then be obtained from the flat film material produced in this way using a conventional stamping process, and the access slot can preferably be introduced into the fastening strap by stamping into the respective punched fastening strap. However, there is also the possibility of punching out the fastening strap and punching in the reach-through slot in separate stations.

Thermoplastics can be used as plastic materials in the manufacturing process, in particular polyolefins, polyamides, aramides, PPS, PVC. The processing of thermoplastic elastomers is also possible.

However, biodegradable polymers are used in a particularly advantageous manner, in particular PLA, PHA, PHB, starch and polyolefin-based, biodegradable formulations. Such is the fastening tape or the Cable ties are biodegradable as a whole and thus meet increasingly strict modern environmental regulations. Since cable ties latched in the latched position only release the goods fixed in their enclosing loop for further use by cutting or prying them open and are then often carelessly thrown away when their function is destroyed, it is good for the environment if, as provided according to the invention, the plastic material for the Cable ties biodegrade. Particularly in the area of consumer goods that are manufactured and traded for private use or consumption, it is advantageous if the packaging, including the cable ties used, can be disposed of in an environmentally friendly manner.

The devices used in the chill roll process are state-of-the-art and can be seen in DE 100 39 937 A1 and EP 1 126 764 B1 described. In particular, with the relevant shaping technology, the individual locking parts of the fastening strap can be obtained in the form of hooking structures on a millimeter to nanoscale, which can lead to small fastening straps and cable ties, which can then be used in a space-saving manner for a large number of practical applications are.

The invention also relates to a fastening strap produced according to this method in the manner of a cable tie, which has a hooking part with which sections of the fastening strap can be connected to form a loop, for which the hooking part has at least one penetration slot which is provided with a latching device which has at least interacts with a latching part of the strap, with the fastening strap being formed from a film-like carrier part which, on at least one side as a respective latching part connected to it in one piece, has a head that is widened compared to a stem part, a pure stem part, a nub or a latching rib. The fastening tape obtained in this way is designed as a film product that can be produced continuously and that can be extremely flexibly adapted to a wide variety of applications. Despite the possible low film thickness, the fastening tape is sufficiently tear-resistant and able to securely hold products received in their tape-shaped enclosing space in their position or to securely attach a technical component of any kind to another assignable component.

Furthermore, there is the possibility of equipping a fastening strap with "intelligence" in the form of a transponder, which can be part of a known passive RFID system. In this way, the fastening strap according to the invention, equipped with such identification systems, can be fastened to the wrist of the respective patient, for example also for identifying patients and/or for achieving a dosed medication delivery.

• 1 eine Vorrichtung für den Erhalt eines Befestigungsbandes;
• 2 exemplarisch einen Ausschnitt des mit der Vorrichtung nach der 1 erhaltenen Folienmaterials mit vorstehenden Rastteilen;
• 3 eine weitere Vorrichtung für den Erhalt eines gegenüber der 2 geänderten Befestigungsbandes;
• 4 und 5 mögliche Folienstrukturierungen, wie sie mit der Vorrichtung nach der 1 bzw. der 3 erhaltbar sind;
• 6 ein Stanzbild für den Erhalt möglichst vieler Befestigungsbänder aus einer Folie, wie sie mit einer Vorrichtung nach den 1 oder 3 erhalten ist; und
• 7, 8,9 unterschiedliche Einstanzungen betreffend den Erhalt eines Durchgriffschlitzes im jeweiligen Befestigungsband in einfacher Schlitzform, in H-Form oder in laschenförmiger Bügelform.

The method according to the invention is explained in more detail below using device solutions together with the fastening tape obtained from them using the drawings. Here, in principle and not to scale representation show the

• 1 a device for obtaining a fastening tape;
• 2 exemplarily a section of the with the device after 1 film material obtained with protruding locking parts;
• 3 another device for obtaining a vis-à-vis the 2 modified fastening tape;
• 4 and 5 possible foil structuring, as with the device according to the 1 or the 3 are obtainable;
• 6 a stamped image for obtaining as many fastening straps from a film, as with a device according to 1 or 3 is received; and
• 7 , 8th , 9 different stampings relating to obtaining a reach-through slit in the respective fastening strap in the form of a simple slit, in the form of an H or in the form of a strap.

The 1 shows a schematic representation of the essential parts of a device for carrying out the method according to the invention with an extruder head 10, which is designed as a slot die and serves as a feed device for a plastic material in a plastic or liquid state, in particular a thermoplastic material, as the film material, the width of which corresponds to that of the fastening tapes to be produced , the gap between a pressure tool and a mold is supplied. A pressure roller 12 is provided as the pressure tool, and the forming tool is a forming roller denoted as a whole by 14 . Both reels are in the in 1 are driven in the directions of rotation indicated by arc arrows 16 and 18, so that a conveying gap is formed between them, through which the plastic film is conveyed in the direction of transport, while at the same time the plastic material is formed into the carrier part 20 with a carrier surface 22 in the gap as a shaping zone and the carrier part 20 on the on the mold roller 14 adjacent side 22 by shaping elements in the form of individual mold cavities 24 of the mold roller 14 to form individual locking parts 28 is given the required shape, these locking parts 28 being arranged vertically above on the support surface 12 .

For this shaping purpose, the shaping roller 14 has a cylindrical screen 26 with the individual shaping cavities 24 on the outer circumference. Furthermore, the individual mold cavities 24, which is not shown in more detail, are regularly distributed over the outer circumference of the mold roller 14 in the usual way, with the distribution and the number being freely selectable. Each mold cavity 24 is closed off in a largely media-tight manner from the outer circumference of the mold roller 14 viewed inwardly in the direction of the axis of rotation of the mold roller 14 .

As the 2 shows, the means of the device after the 1 film product obtained on the output side, the carrier part 20, which extends in the longitudinal and transverse direction and can be predetermined in length, which on its viewed in the direction of the 2 Seen, the upper support surface 22 carries the individual latching parts 28 which are an integral part of the film-like support part 20 in the context of the shaping process described above. The respective latching part 28 has an upwardly projecting stem part 30, the free end of which opens out into a polygonal head 32, in particular a hexagonal shape, and the head 32 protrudes at the edge essentially over the stem part 30, with all heads 32 extending along extend parallel to the support surface 22 in a common horizontal plane.

Galvanic coating processes have proven to be suitable for obtaining the aforementioned mold cavities 24 in the screen 26 with their rotationally symmetrical structure in the area of the respective stem part, in particular in the form of a hyperboloid, in which first a cylindrical mold cavity (not shown) is provided with a coating material in this way , until the convex trajectory is set, which is suggested by the representation according to the 1 results.

By means of a deflection roller 34, the flat carrier part 20 with its protruding locking parts 28 is pulled out of the mold cavities 24 of the screen 26 of the mold roller 24, with the plastic material still being in the partially plastic state during the pull-out movement, which helps to facilitate the demolding process. The film material formed in this way is then passed on after leaving the deflection roller 34 to a punching device 36 which has a stationary counter-holder plate 38 with a punch 40 arranged above it, which in the direction of view of the 1 viewed along the direction of the double arrow 42 can be moved up and down for a punching operation. The stamping die 40 has a stamping geometry as shown in 6 is reproduced, ie the 8 fastening straps 44 shown there can be obtained as part of the punching out of the foil-shaped carrier part 20 with its protruding latching parts 28 . As part of the pertinent punching process, the free tops of the heads 32 are then guided in a supporting manner along the top of the counter-holder 38 . With regard to the after 6 The die-cut image obtained is in this respect the latching parts 28 on the side of the individual fastening straps 44 that faces away from the viewing direction. However, in an embodiment that is not shown in detail, it is also possible to punch out the underside of the strip 44 by means of the punch 40 and the latching parts 28 via the counter-retaining plate 38 to be supported from above if necessary.

In a further sequence of the film transport, the initially punched fastening straps 44 (partially shown as a punched-out part in phantom) in their position within the film web after 6 remain and are subsequently fed to a stamping device 46, which in turn has a plate-shaped counter-holder 48 and arranged above it and movable along the double arrow 42, the stamping tool 50 is present. The pertinent stamping tool 50 allows the introduction of a line-shaped penetration slot 52 after 7 , an H-shaped reach-through slot 52 after the 8th or a tab-shaped passage after the 9 , wherein preferably only one type of reach-through slot 52 is realized. It goes without saying that the reach-through slots 52 to be introduced into a widened head part 54 of each fastening strap 44 according to the representation according to FIG 6 are always to be arranged alternately in the sequence on opposite end sides of the fastening strap 44, wherein in a particularly preferred embodiment the punching device 40 for punching out the fastening straps 44 from the film-like carrier part 20 and the punching tool 50 for obtaining the penetration slots 52 on the head parts 54 of each fastening strap 44 combined in a common production tool (not shown) and can therefore be produced at the same time. A plurality of devices 40, 50 arranged in series can be provided for continuous production. However, there is also the possibility of designing the punching device 40 and the punching device 50 as a cylindrical rotary tool in order to ensure continuous production in this way.

The particular in the 7 , 8th and 9 illustrated different types of reach-through slots 52 are selected from their slot width such that the free end of the tape 6 through the end can be passed through the slot 52, the individual latching parts 28 then being latched with a latching device 58 which is formed by the wall or surface parts of the head part 54 of the fastening strap 44 delimiting the reach-through slot 52. In particular, these wall parts can form tab-shaped cutouts 60, as shown in FIGS 8th and 9 is shown, which then carry out the latching with the latching parts 28 in an elastically yielding manner with their respective free edges. The width of the fastening strap 44 is preferably selected in such a way that the width of the free end of the strap 56 fits through the reach-through slot 52 in any case. In order to ensure this, it is provided that the punched cross section of the fastening strap 44 increases in the direction of the head part 54, as is shown in FIGS 6 until 9 is shown. Otherwise, the fastening strap 44, which is designed in the manner of a cable tie, is in the initial state as in FIGS 6 until 9 shown, a sheet or foil product with a small wall thickness and the individual latching parts 28 are on top of the fastening strap 44 before. Furthermore, in an embodiment that is not shown in more detail, there is the possibility of introducing slits on the side of the fastening strip 44 at discrete distances from one another, which can then hook together with assignable edges of the respective reach-through slit 52 to form a loop.

Various embodiments of locking parts 28 are in the 4 shown, seen in the direction of this figure, on the far left, the previously described solution with handle part 30 and head 32 is reproduced in a greatly simplified representation. However, there is also the possibility, as shown on the right, of configuring the respective latching part 28 from headless pure handle parts 30 . There is also the possibility, as again shown on the right, of forming the respective latching part 28 from a latching rib 62, which can then also extend across the entire fastening strip 44, with a subdivision into partial rib pieces (not shown) also being possible in this regard. Far right according to the representation after the 4 is then an embodiment of the locking parts 28, shown in the form of individual knobs 64 in a schematic representation. It goes without saying that the respective latching parts 28 are arranged in rows and columns, also in an irregular arrangement, multiple times into the plane of the drawing on the carrier surface 22 of the carrier part 20 . Ultimately, the configuration of the respective mold cavity 24 specifies the shape of the respective locking part 28 and further configurations are conceivable here. The locking parts 28 could also be designed with stem parts 30 on the support surface 22 of the support part 20 in an inclined position in order to produce better locking with the locking device of the fastening strap 44 in this way. Depending on the choice of plastic material and the selected thickness for the carrier part 20, the fastening strap 44 can also be provided with a certain inherent elasticity, so that an elastically yielding cable tie is then realized that can act on the item to be encompassed with a pretensioning force.

The film-like carrier part 20 preferably has a film thickness of between 0.1 and 1 mm, preferably between 0.2 and 0.9 mm, particularly preferably between 0.3 and 0.7 mm and the height of the respective one-piece design with the carrier part 20 Measured from its foot side, i.e. at the transition point to the carrier surface 22, the locking part is selected to be between 0.1 and 1 mm, preferably between 0.2 and 0.5 mm. Other dimensions are easily possible here as long as they do not impair the overall function of the fastening strip 44 or the cable tie. In order to be able to thread the free end of the strap 56 better into the reach-through slot 52, it can be provided that the free end of the strap is designed to be pointed or tapered. By pushing the latching device 58, i.e. by disengaging the tab-like wall parts from the gaps between adjacent latching parts 28, the cable tie can also be released again in a simple manner, specifically with low actuating forces due to the small film thickness. A destructive tearing apart or cutting apart of the fastening strap 44 is then not necessary in this respect.

The device solution after 3 relates to a method for producing the fastening strap 44, again with a large number of latching parts 28 formed in one piece with a carrier part 20, in which again a suitable plastic material in a plastic or liquid state is fed to the gap between now two drivable molding rollers 14 and these are driven in this way, that the carrier part 20 is formed in the gap and is conveyed in a transport direction in the direction of the deflection roller 34, with the locking parts 28 now being formed offset to one another on both sides of the carrier part 20 by shaping elements 24 acting on both sides of the gap. The continuous mold cavities 24 of the first screen 26 and the corresponding mold cavities 24 of a further screen 26 serve as shaping elements for this purpose 3 the respective mold cavities 24 of each sieve 26 can be of the same design, resulting in associated latching part structures according to the first three exemplary embodiments, seen from left to right in FIG 5 ; but these can also be designed differently, so that, for example, a nub structure results, such as in the 5 shown on the far right, in which the nubs 64 arranged at the top have a greater vertical spacing from the upper side of the support surface 22 than the nubs 64 arranged underneath 5 , which schematically shows the end product of the tape solution according to the 3 shows, has for the carrier part 20 two opposite parallel carrier surfaces 22 from which the locking parts 28 protrude as shown. It is understood that in an embodiment according to the 5 with latching parts 28 on two opposite sides of the carrier part 20 on both sides of the latching device 58 there is a latching with the tab-shaped cutouts 60 of the head part 54 .

At this point it should be pointed out that the groups of mold cavities 24 of the individual mold rollers 14 can also have a larger radial distance from one another on the peripheral side, so that the carrier part 20 has areas with the locking parts 28 and has areas that are free of locking parts 28 are held. In particular, for the function of a cable tie, it is only necessary for the latching parts 28 for latching with the latching device 58 to be present in the direction of the free strap end 56 of the fastening strap 44 . In the area of the fastening strap 44, which essentially forms the encircling loop of the cable tie, the latching parts 28 can also be dispensed with. However, if such snap-in parts 28 are used to position piece goods to be received in the encircling loop in the holding position, the presence of snap-in parts 28 over the entire length of the fastening strap 44 can be advantageous.

• Biologisch abbaubares Kunststoffmaterial, wie
  • - Polycaprolacton (PCL),
  • - Polybutyrat (PBAT),
  • - Polybutylensuccinat (PBS).
• Biobasierte Kunststoffmaterialien, wie
  • - Celluloseacetat (CA),
  • - biobasiertes Polyethylen (Bio-PE),
  • - Polyethylenfuranoat (PEF),
  • - biobasiertes Polyamid (Bio-PA),
  • - biobasiertes Polyethylenterephthalat (Bio-PET).
• Biobasiertes biologisch abbaubares Kunststoffmaterial, wie
  • - Polyactid (PLA),
  • - Polyhydroxyalkanoat (PHA),
  • - Thermoplastische Elastomere (TPS),
  • - Stärke,
  • - polyolefinbasierte, biologisch abbaubare Formulierungen.

It is of particular advantage to produce the entire fastening strap 44 from a bio-based or biodegradable plastic material. The following plastic materials are particularly preferred for this purpose:

• Biodegradable plastic material, such as
  • - Polycaprolactone (PCL),
  • - polybutyrate (PBAT),
  • - Polybutylene succinate (PBS).
• Bio-based plastic materials, such as
  • - cellulose acetate (CA),
  • - bio-based polyethylene (bio-PE),
  • - polyethylene furanoate (PEF),
  • - bio-based polyamide (Bio-PA),
  • - bio-based polyethylene terephthalate (bio-PET).
• Bio-based biodegradable plastic material, such as
  • - polyactide (PLA),
  • - Polyhydroxyalkanoate (PHA),
  • - Thermoplastic Elastomers (TPS),
  • - Strength,
  • - Polyolefin-based, biodegradable formulations.

Irrespective of this, conventional plastic materials can also be used for production, which enable the respective fastening strap 44 with its latching parts 28 to be produced cost-effectively. Furthermore, there is the possibility of providing the individual fastening straps 44 with a transponder 66 in the manner of a computer chip for RFID technology. In this way, a wide variety of types of information can be stored and read on the transponder 66, such as product information, patient data, medication information, etc.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 3038944 B1 [0002]
• DE 19651835 A1 [0003]
• DE 10039937 A1 [0008]
• EP 1126764 B1 [0008]

Claims (10)

Method for producing a fastening strap (44) which has a hooking part (54) with which sections of the fastening strap (44) can be connected to form a loop, for which the hooking part (54) has at least one passage slot (52) which is equipped with a latching device ( 58) which interacts with at least one assignable locking part (28) of the fastening strap (44) as soon as the free end (56) of the strap passes through the slot (52), characterized by the following method steps - extrusion of a plastic material and at least partial introduction the same into mold cavities (24) of a rotating mold roller (14) with the formation of latching parts (28) arranged protruding on a carrier part (20), - removing the latching parts (28) from the mold cavities (24) while simultaneously removing the carrier part (20) from the shaping roller (14), - cutting off individual fastening straps (44) from the carrier part (20), and - introducing the respective reach-through slot (52) together with the latching device (58). procedure after claim 1 , characterized in that the individual fastening straps (44) are separated from the carrier part (20) by means of punching. procedure after claim 1 or 2 , characterized in that the penetration slot (52) is made in the fastening strap (44) by means of stamping, preferably at the same time as the respective associated fastening strap (44) is stamped out of the carrier part (20). Method according to one of the preceding claims, characterized in that the mold cavities (24) of the mold roller (14) are produced from the screen structure of at least one forming screen (26) which is drawn onto a roller body. Method according to one of the preceding claims, characterized in that to produce the fastening strap (44) with the latching parts (28) on both sides of the carrier part (20), two shaping rollers (14) arranged opposite one another are used, between which the carrier part (20) to be led. Method according to one of the preceding claims, characterized in that as part of the punching process for obtaining the fastening straps (44), the respective hooking part of a fastening strap is arranged as a head part (54) on the end thereof with a head part (54) arranged adjacent in the context of the punching pattern in between picks up a tape end (56) of a tape (44) while maintaining an edge spacing. Method according to one of the preceding claims, characterized in that the carrier part (20) forms a carrier film and has a film thickness of between 0.1 and 1 mm, preferably between 0.2 and 0.9 mm, particularly preferably between 0.3 and 0. 7 mm and the height of the respective locking part (28) formed in one piece with the carrier part (20), measured from its base side, is selected between 0.1 and 1 mm, preferably between 0.2 and 0.5 mm. Method according to one of the preceding claims, characterized in that the plastic material used for the production of the fastening straps (44) is selected at least partially from bio-based and/or biodegradable plastics. Method according to one of the preceding claims, characterized in that after receipt of the fastening strap (44) or when it is created, it is provided with at least one transponder (66), preferably in the area of the hooking part (54). Fastening strap, in particular produced by a method according to one of the preceding claims, which has a hooking part (54) with which sections of the fastening strap (44) can be connected to form a loop, for which the hooking part (54) has at least one reach-through slot (52) which is provided with a latching device (58) which interacts with at least one latching part (28) of the strap (44), characterized in that the fastening strap (44) is formed from a film-like carrier part (20) which is on at least one side (22nd ) as a respective locking part (28) connected in one piece to the carrier part (20) compared to a handle part (30) widened head (32), a handle part (30), a nub (64) or a locking rib (62).

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