DE1134195B - Device for welding plastics, in particular plastic films - Google Patents
Device for welding plastics, in particular plastic filmsInfo
- Publication number
- DE1134195B DE1134195B DEF22287A DEF0022287A DE1134195B DE 1134195 B DE1134195 B DE 1134195B DE F22287 A DEF22287 A DE F22287A DE F0022287 A DEF0022287 A DE F0022287A DE 1134195 B DE1134195 B DE 1134195B
- Authority
- DE
- Germany
- Prior art keywords
- heating
- heating wire
- pieces
- welding
- resistors
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/22—Heated wire resistive ribbon, resistive band or resistive strip
- B29C65/221—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip
- B29C65/222—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip comprising at least a single heated wire
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/22—Heated wire resistive ribbon, resistive band or resistive strip
- B29C65/221—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip
- B29C65/222—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip comprising at least a single heated wire
- B29C65/223—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip comprising at least a single heated wire comprising several heated wires
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/22—Heated wire resistive ribbon, resistive band or resistive strip
- B29C65/228—Heated wire resistive ribbon, resistive band or resistive strip characterised by the means for electrically connecting the ends of said heated wire, resistive ribbon, resistive band or resistive strip
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
- B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
- B29C66/112—Single lapped joints
- B29C66/1122—Single lap to lap joints, i.e. overlap joints
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/22—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns
- B29C66/221—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns being in the form of a sinusoidal wave
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/22—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns
- B29C66/227—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns being in the form of repetitive interlocking undercuts, e.g. in the form of puzzle cuts
- B29C66/2272—Teardrop-like, waterdrop-like or mushroom-like interlocking undercuts
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/22—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns
- B29C66/227—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns being in the form of repetitive interlocking undercuts, e.g. in the form of puzzle cuts
- B29C66/2276—Other specific local geometries of interlocking undercuts not provided for in B29C66/2272 - B29C66/2274
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/22—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being in the form of recurring patterns
- B29C66/229—Other specific patterns not provided for in B29C66/221 - B29C66/227
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
- B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
- B29C66/43—Joining a relatively small portion of the surface of said articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/80—General aspects of machine operations or constructions and parts thereof
- B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
- B29C66/818—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps
- B29C66/8182—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps characterised by the thermal insulating constructional aspects
- B29C66/81821—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps characterised by the thermal insulating constructional aspects of the welding jaws
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/80—General aspects of machine operations or constructions and parts thereof
- B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
- B29C66/818—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps
- B29C66/8183—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps characterised by the thermal conducting constructional aspects
- B29C66/81831—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps characterised by the thermal conducting constructional aspects of the welding jaws
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/80—General aspects of machine operations or constructions and parts thereof
- B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
- B29C66/818—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps
- B29C66/8185—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the cooling constructional aspects, or by the thermal or electrical insulating or conducting constructional aspects of the welding jaws or of the clamps ; comprising means for compensating for the thermal expansion of the welding jaws or of the clamps comprising means for compensating for the thermal expansion of the welding jaws or of the clamps
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/24—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools characterised by the means for heating the tool
- B29C65/30—Electrical means
- B29C65/305—Electrical means involving the use of cartridge heaters
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/50—General aspects of joining tubular articles; General aspects of joining long products, i.e. bars or profiled elements; General aspects of joining single elements to tubular articles, hollow articles or bars; General aspects of joining several hollow-preforms to form hollow or tubular articles
- B29C66/51—Joining tubular articles, profiled elements or bars; Joining single elements to tubular articles, hollow articles or bars; Joining several hollow-preforms to form hollow or tubular articles
- B29C66/52—Joining tubular articles, bars or profiled elements
- B29C66/522—Joining tubular articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/80—General aspects of machine operations or constructions and parts thereof
- B29C66/81—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps
- B29C66/814—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps
- B29C66/8141—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps characterised by the surface geometry of the part of the pressing elements, e.g. welding jaws or clamps, coming into contact with the parts to be joined
- B29C66/81427—General aspects of the pressing elements, i.e. the elements applying pressure on the parts to be joined in the area to be joined, e.g. the welding jaws or clamps characterised by the design of the pressing elements, e.g. of the welding jaws or clamps characterised by the surface geometry of the part of the pressing elements, e.g. welding jaws or clamps, coming into contact with the parts to be joined comprising a single ridge, e.g. for making a weakening line; comprising a single tooth
Description
Vorrichtung zum Schweißen von Kunststoffen, insbesondere von Kunststoffolien Die Erfindung bezieht sich auf elektrisch beheizte Vorrichtungen zum Schweißen von Kunststoffen, insbesondere Kunststoffolien und Kunststoffschläuchen.Device for welding plastics, in particular plastic films The invention relates to electrically heated devices for welding Plastics, in particular plastic films and plastic hoses.
Das Verschweißen von Kunststoffen erfolgt bekanntlich, indem die zu verbindenden Kunsfstoffbahnen so aufeinandergelegt werden, wie sie nach dem Verschweißen zusammengefügt sein sollen. Dann werden, nachdem oder während an den zu verschweißenden Stellen die Temperatur des Kunststoffes auf einen Bereich erhöht ist, in dem der Kunststoff sich in einem gewissen plastischen oder zähflüssigen Zustand befindet, die zusammenzufügenden Kunststoffteile unter Druck miteinander verbunden. Hierzu werden meist Vorrichtungen verwendet, mit deren Hilfe eine mehr oder weniger lange Schweißnaht oder eine größere Zahl in Reihe angebrachter punktförmiger Schweißstellen in einem Arbeitsgang oder einer Folge erzeugt wird. It is known that plastics are welded by the To be connected Kunsfstoffbahnen be placed on top of each other as they are after welding should be put together. Then, after or during to the to be welded Set the temperature of the plastic to an area where the Plastic is in a certain plastic or viscous state, the plastic parts to be joined together under pressure. For this devices are mostly used, with the help of which a more or less long Weld seam or a larger number of spot welds attached in a row is generated in one operation or in a sequence.
Das Verschweißen von Kunststoffen wirft nun bezüglich der Anordnung und Ausbildung der elektrischen Heizwiderstände in den für die Verschweißung benutzten Vorrichtungen besondere technische Probleme auf. Diese ergeben sich aus den speziellen Anforderungen, welche die Anbringung einer einwandfreien Kunststoffschweißnaht an die Ausbildung der Schweißvorrichtung bzw. an das hierbei zur Anwendung kommende Verfahren stellt. So ist es erforderlich, daß die Heizwiderstände der Schweißvorrichtung durch einen kurzen Stromimpuls auf die gewünschte Temperatur, also Schweißtemperatur, gebracht und nach Beendigung des Stromimpulses sofort wieder abgekühlt werden können. Es kommt weiterhin darauf an, daß jede Stelle des Heizleiters dieselbe Temperatur hat. Die Gewährleistung einer solchen Temperaturkonstanz ist jedoch bei der Herstellung von langen geraden oder kurvenförmigen Schweißnähten, insbesondere solchen, die eine geschlossene Kurve bilden, schwierig. Es ist deshalb bereits vorgeschlagen worden, bei elektrisch beheizten Schweißstempeln die Stromzufuhr zu den der Form der Schweißnaht angepaßten Heizwiderständen an verschiedenen Stellen erfolgen zu lassen, also eine Anzahl hintereinander in Reihenfolge angeordneter Widerstände parallel zu schalten. Trotzdem bieten die Längenausdehnung der Widerstände und die infolgedessen in diesen auftretenden Schubkräfte Schwierigkeiten, da sie Knickungen und Verformungen der Widerstände verursachen können und daher deren Lebensdauer herabsetzen. Tatsächlich sind selbst kurze Widerstände vielfach bereits nach einem kurzen Gebrauch an der linken oder rechten Anschlußseite beschädigt. Es ist auch nicht möglich, diesen Nachteil dadurch zu beheben, daß die einzelnen Widerstände mit gewissen Zwischenräumen aneinandergereiht werden, denn dadurch würde die Temperatur des Kunststoffes an den Stoßstellen der Widerstände niedriger sein als im übrigen Bereich derselben. Da bekanntlich für die Schweißung von Kunststoffen nur ein geringer Temperaturbereich zur Verfügung steht, hat ein solcher Unterschied in der Beheizung, insbesondere bei einer längeren Schweißstelle, eine ungleichmäßige Schweißung zur Folge, denn entweder ist die Temperatur an den Stoß stellen zu niedrig oder innerhalb des von der Elektrode selbst überdeckten Bereiches zu hoch. The welding of plastics now raises with regard to the arrangement and design of the electrical heating resistors in those used for welding Devices on special technical problems. These result from the special Requirements, which the application of a perfect plastic weld seam the design of the welding device or the one used here Procedure provides. So it is necessary that the heating resistors of the welding device by a short current pulse to the desired temperature, i.e. welding temperature, brought and can be cooled down again immediately after the end of the current pulse. It is also important that every point on the heating conductor has the same temperature Has. The guarantee of such a temperature constancy is, however, in the production of long straight or curved welds, especially those that Form a closed curve, difficult. It is therefore already proposed been, in the case of electrically heated welding dies, the power supply to the form the weld seam adapted heating resistances take place at different points leave, i.e. a number of resistors arranged one behind the other in sequence to connect in parallel. Nevertheless, the linear expansion of the resistors and the As a result, difficulties occurring in these shear forces, since they are buckling and deformations of the resistors and therefore their service life reduce. In fact, even short resistances are often after one short use damaged on the left or right side of the connection. It is also not possible, to remedy this disadvantage that the individual resistors be strung together with certain gaps, because that would increase the temperature of the plastic at the joints of the resistors must be lower than the rest Area of the same. As is well known, only a small amount for welding plastics Temperature range is available, has such a difference in heating, especially with a longer weld, an uneven weld for Consequence, because either the temperature at the joints is too low or within of the area covered by the electrode itself is too high.
Die vorstehenden Ausführungen zeigen, daß die Konstruktion von für die Kunststoffschweißung geeigneten Vorrichtungen ganz spezielle Fragen aufwirft, die mit denjenigen, wie sie bei den üblichen Heizgeräten, wie Heizplatten, Heizkörpern usw., auftreten, überhaupt nicht vergleichbar sind, so daß auch dem Fachmann durch die auf diesem Gebiet bekannten Maßnahmen keine Anhaltspunkte für die Lösung der der Erfindung zugrunde liegenden Aufgabe vermittelt werden konnten. Abgesehen davon wären die von den verschiedenen Heizgeräten her bekannten Arbeitsmittel bei ihrer Übertragung auf das Gebiet der vorliegenden Erfindung nicht geeignet, den sich aus vorstehendem ergebenden und an eine Schweißvorrichtung für Kunststoffe zu stellenden Anforderungen gerecht zu werden. So benötigen die Heizeinrichtungen bei den bekannten Heizgeräten eine verhältnismäßige lange Zeit zum Anheizen und Abkühlen. Soweit hierbei flach gewickelte Leiter zur Anwendung kamen, waren diese nicht derart ausgebildet, daß bei einer mit einem solchen Leiter etwaig durchgeführten Verschweißung von Kunststoífen jede Stelle auf dieselbe Temperatur hätte erhitzt werden können, was jedoch im Hinblick auf die Anbringung einer einwandfreien Schweißnaht wichtig ist; denn bei vielen Kunststoffen ist, wie bereits erwähnt, das Temperaturintervall, das für die Verschweißung des Kunststoffes weder unter- noch überschritten werden darf, sehr eng. The foregoing shows that the construction of for the devices suitable for plastic welding raise very specific questions, those with those as they are with the usual heating devices, such as hot plates, radiators etc., occur, are not at all comparable, so that even the expert through the measures known in this area do not provide any indication of the solution to the the object underlying the invention could be conveyed. Apart from this would be the work equipment known from the various heating devices with her Transfer to the field of the present invention does not suit the itself the above and to be placed on a welding device for plastics To meet requirements. So need the heating devices in the known Heating appliances take a relatively long time to heat up and cool down. So much for this flat-wound conductors were used, they were not designed in such a way that that with one with such a head performed welding plastic could have heated every point to the same temperature, but this is important with regard to the creation of a perfect weld seam is; because with many plastics, as already mentioned, the temperature interval is that are neither exceeded nor fallen below for the welding of the plastic may, very tight.
Die vorerwähnten Nachteile und Schwierigkeiten sollen durch die Erfindung behoben werden. Hierbei geht die Erfindung von den bekannten Vorrichtungen zum Schweißen von Kunststoffen aus, deren elektrische Heizwiderstände in parallel geschaltete Stücke unterteilt sind. Erfindungsgemäß sollen nun die Widerstände aus an sich bekannten, in einer Ebene liegenden, quer zur Hauptrichtung in Windungen geführten Heizdrahtstücken mit jeweils an ihren Enden vorgesehenen Anschluß stellen an eine elektrische Leitung bestehen. Auf diese Weise wird die durch die Ausdehnung beim Erwärmen oder Verkürzung beim Abkühlen hervorgerufene Längenänderung von den wechselnden Windungen abgefangen, so daß die Temperaturänderung keinerlei ungünstige Wirkung auf die Widerstände oder auf die Schweißnaht hat. The aforementioned disadvantages and difficulties are addressed by the invention be resolved. The invention is based on the known devices for welding made of plastics whose electrical heating resistors are connected in parallel Pieces are divided. According to the invention, the resistors should now consist of known, Heating wire pieces lying in one plane, transversely to the main direction in turns with each provided connection at their ends to an electrical line exist. In this way, the expansion when heated or shortened Changes in length caused by cooling are intercepted by the alternating windings, so that the temperature change has no adverse effect on the resistors or on the weld.
Damit aber auch an den Stoßstellen der Heizdrähte keinerlei Temperaturunterschiede auftreten und die Schweißnaht durchlaufend gleiche Güte aufweist, können das Ende des einen und der Anfang des nächsten Heizdrahtstückes möglichst dicht nebeneinander eingebettet werden, so daß die beheizte Fläche praktisch kaum unterbrochen wird. Es ist auch zweckmäßig, die Heizdrahtstücke so aneinanderzureihen, daß jeweils der letzte Windungsteil eines vorangehenden Heizdrahtstückes den ersten Windungsteil des folgenden Heizdrahtstückes hintergreift, wobei jedes Heizdrahtstück getrennte, besondere Anschlußstellen für die elektrischen Anschlußleitungen besitzt. This means that there are no temperature differences at the joints between the heating wires occur and the weld seam has consistently the same quality, the end can the one and the beginning of the next piece of heating wire as close together as possible are embedded, so that the heated surface is hardly interrupted. It is also useful to string the heating wire pieces together so that each of the last turn part of a preceding heating wire piece the first turn part of the following piece of heating wire engages behind, with each piece of heating wire having separate, has special connection points for the electrical connection lines.
Gegebenenfalls können auch die aufeinanderfolgenden Heizdrahtstücke durch Löten oder auf andere Weise miteinander verbunden werden und an die Verbindungsstellen Stromzuführungen bzw. -ableitungen angeschlossen werden. Der Strom wird dann jeweils von einer solchen Verbindungsstelle durch in zwei entgegengesetzten Richtungen verlaufende Heizdrähte zu je einer Leitung mit anderer Spannung geführt, so daß beispielsweise in der Länge des gesamten Widerstandes Plus- und Minus anschlüsse abwechseln. If necessary, the successive pieces of heating wire can also be used be connected together by soldering or in some other way and to the connection points Power supply lines or leads are connected. The current is then each from such a junction by running in two opposite directions Heating wires led to one line each with a different voltage, so that, for example Alternate plus and minus connections along the length of the entire resistor.
Ein weiterer Vorteil der Widerstände nach der Erfindung besteht darin, daß diese sowohl vor als auch nach der Einbettung flexibel sind und daher nicht nur die Längenänderungen ausgleichen, sondern auch verschiedensten Nahtformen angepaßt werden können. Another advantage of the resistors according to the invention is that that these are flexible both before and after embedding and therefore not only compensate for changes in length, but also adapt to a wide variety of seam shapes can be.
Die Widerstände können in wärmeleitenden Werkstoff eingebettet werden, der flexibel oder als fester Widerstandsträger der vorgesehenen Nahtform angepaßt sein kann. Es ist zweckmäßig, diesem Widerstandsträger einen schwalbenschwanzförmigen Querschnitt zu geben, so daß er in einer plattenförmigen Vorrichtung guten Halt besitzt. Als Werkstoff für den Widerstandsträger kann Hartgewebe, Kunststoff mit höherer Wärmefestigkeit, gegebenenfalls mit Metalluntermischung od. dgl., verwendet werden. The resistors can be embedded in thermally conductive material, which is flexible or adapted as a fixed resistance carrier to the intended seam shape can be. It is advisable to give this resistor support a dovetail shape To give cross-section, so that it holds good in a plate-shaped device owns. Hard fabric, plastic can be used as the material for the resistance carrier higher heat resistance, if necessary with mixed metal or the like. Used will.
Vor oder bei der Einbettung können die aneinandergereihten Heizdrähte von einem pulverförmigen oder feinkörnigen, gegebenenfalls gepreßten, wärmeleitenden Material umgeben werden, beispielsweise von silikonvermengtem Metallstaub. Dadurch ergibt sich ein praktisch ununterbrochen fortlaufendes Heizband, das allseitig hinreichend mit dem wärmeleitenden Silikonheizbelag umgeben ist und mit diesem Belag eine der Nut des Widerstandsträgers oder der Heizplatte angepaßte Form aufweist und dabei leicht in diese Nut gedrückt werden kann. Bei dieser Einbettung sind zusätzlich Heizkörperbeläge aus Tetrafluoräthylen, silikongeschichteter Glasseide od. dgl. nicht erforderlich. Die Anordnung ermöglicht zudem ein schnelles Auswechseln von Heizdrahtstücken oder des gesamten Widerstandes, so daß bei einer Reparatur die Betriebsunterbrechung nur sehr kurz ist. Before or during embedding, the strung together heating wires from a powdery or fine-grained, optionally pressed, thermally conductive Material are surrounded, for example by silicon-mixed metal dust. Through this results a practically uninterrupted heating tape that is sufficient on all sides is surrounded by the thermally conductive silicone heating covering and with this covering one of the Groove of the resistance carrier or the heating plate has adapted shape and thereby can be easily pressed into this groove. With this embedding there are additional Radiator coverings made of tetrafluoroethylene, silicone-coated glass fiber or the like. not mandatory. The arrangement also enables quick replacement of Heating wire pieces or the entire resistor, so that during a repair the Business interruption is only very brief.
Mit derartigen Widerständen kann das bekannte Impulsschweißverfahren, auch mit Dauerbeheizung, angewendet werden. Vor allem ist der Vorteil gegeben, daß infolge des Ausgleiches der Längenänderungen auch unter hohen Temperaturen gearbeitet werden kann, also eine entsprechend ausgebildete Schweißeinrichtung auch bei Werkstoffen angewendet werden kann, deren Schweißtemperatur höher als normal liegt. Es hat sich gezeigt, daß die Vorrichtung nach der Erfindung auch bei höheren Temperaturen eine Dauerbeheizung aushalten kann, so daß einseitige Schweißungen von 1,5 mm Stärke und darüber durchgeführt werden können, ohne daß an der Schweißnaht Querschnittsveränderungen des zu verschweißenden Materials auftreten. With such resistors, the well-known pulse welding process, can also be used with permanent heating. The main advantage is that because of the compensation of the changes in length worked even under high temperatures can be, so a correspondingly trained welding device even with materials can be used whose welding temperature is higher than normal. It has shown that the device according to the invention even at higher temperatures Can withstand continuous heating, so that one-sided welds 1.5 mm thick and can be carried out over it without changes in cross-section at the weld seam of the material to be welded occur.
Es ist außerdem möglich, durch entsprechende Bemessung der Windungsbreite unterschiedliche Schweißnahtbreiten bis zur beliebig großen Flächenbildung ohne umständliches Ausgleichen und ohne zusätzliche Wärmezufuhr herzustellen. Es können daher auch leicht Figuren oder Schriften auf den Kunststoffbahnen angebracht werden. Dabei ist lediglich zu beachten, daß die einzelnen Heizdrahtstücke gleiche Länge und Wicklungsdichte aufweisen. It is also possible by dimensioning the winding width accordingly different weld seam widths up to any large area formation without cumbersome balancing and to produce without additional heat supply. It can therefore figures or writings can easily be attached to the plastic sheets. It is only necessary to ensure that the individual pieces of heating wire are the same length and winding density.
Nach der Erfindung können die Heizwiderstände auch beidseitig beschichtet und gegebenenfalls in einem Träger so angebracht werden, daß sie nach zwei Seiten beheizen können. Diese Anwendung ist besonders für das Verschweißen von Flachbeuteln, von aneinandergesetzten Schlauchstücken u. dgl. geeignet und ermöglicht es, solche Schweißungen in einem Arbeitsgang vorzunehmen. According to the invention, the heating resistors can also be coated on both sides and optionally in a carrier so that they are on two sides can heat. This application is particularly suitable for welding flat bags, of juxtaposed hose pieces and the like. Suitable and enables such To carry out welds in one operation.
Mit übereinandergelagerten Heizvorrichtungen kann eine Ober- und Unterschweißung des zwischen die Heizvorrichtungen gelegten Kunststoffes in einem Arbeitsgang durchgeführt werden. Schlauchteile können gleichzeitig an den Innenseiten und von oben und unten her an den Außenseiten erhitzt werden, so daß mit Hilfe solcher unter Zwischenfügung von Kunststoffbahnen übereinander angeordneter Heizvorrichtungen ein schnelles, gründliches und gleichmäßiges Verschweißen erfolgt. Infolge der Biegsamkeit der einzelnen Heizdrahtstücke ist auch ein Schweißen mit Höhen- und Tiefenunterschieden, also ein Verschweißen unebener Flächen möglich. With superimposed heating devices, an upper and Under-welding of the plastic placed between the heating devices in one Operation to be carried out. Hose parts can be attached to the insides at the same time and heated from above and below on the outsides, so that with the help of such heating devices arranged one above the other with the interposition of plastic sheets rapid, thorough and even welding takes place. As a result of flexibility of the individual heating wire pieces is also a welding with height and depth differences, thus welding of uneven surfaces is possible.
Die Zeichnungen bringen einige Beispiele von erfindungsgemäß ausgebildeten Widerständen und ihrer Einbettung in schematischer Darstellung. The drawings bring some examples of those designed according to the invention Resistances and their embedding in a schematic representation.
Fig. 1 zeigt ein Heizdrahtstück in Aufsicht, Fig. 2 zwei aneinandergereihte Heizdrahtstücke, Fig. 3 mehrere miteinander verbundene Heizdrahtstücke in Aufsicht und Fig. 4 eine Seitenansicht zu Fig. 3; Fig. 5 stellt einen Querschnitt durch einen eingebetteten Widerstand und Widerstandsträger in einer Schweißvorrichtung dar; Fig. 6 zeigt im Querschnitt Heizvorrichtungen in Arbeitslage; Fig. 7 bringt einen Querschnitt durch eine erfindungsgemäße Vorrichtung in einem größeren Maßstab als Fig. 5, Fig. 8 einige aneinandergereihte Heizdrahtstücke und Fig. 9 einen Querschnitt durch eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung; Fig. 10 und 11 zeigen Querschnitte durch weitere Ausführungsbeispiele der erfindungsgemäßen Vorrichtung. Fig. 1 shows a heating wire piece in plan view, Fig. 2 shows two strung together Heating wire pieces, Fig. 3 several interconnected heating wire pieces in a plan view and FIG. 4 shows a side view of FIG. 3; Fig. 5 shows a cross section through a embedded resistor and resistor carrier in a welding device; Fig. 6 shows, in cross section, heating devices in the working position; Fig. 7 shows a cross section by a device according to the invention on a larger scale than Fig. 5, Fig. 8 some juxtaposed heating wire pieces and FIG. 9 shows a cross section through a another embodiment of the device according to the invention; Figures 10 and 11 show Cross-sections through further exemplary embodiments of the device according to the invention.
Das in der Fig. 1 dargestellte Heizdrahtstück 1 besteht aus einer Anzahl flach liegender Drahtwindungen mit Anschlußstellen 2 und 3. In der Fig. 2 sind zwei solche Heizdrahtstücke 1 so aneinandergereiht, daß der letzte Windungsbogen des einen Heizdrahtes den ersten Windungsbogen des zweiten hintergreift. The heating wire 1 shown in Fig. 1 consists of a Number of flat-lying wire windings with connection points 2 and 3. In FIG. 2 are two such heating wire pieces 1 lined up so that the last winding arc of the one heating wire engages behind the first winding arc of the second.
Bei den Beispielen der Fig. 3 und 4 sind mehrere Heizdrähte 1 in Reihe miteinander verbunden. An den Verbindungsstellen 2 und 3 ist bei Gleichstrom abwechselnd je eine Plusleitung 4 und eine Minusleitung 5 angeschlossen. In the examples of FIGS. 3 and 4, several heating wires 1 are in Row connected to each other. At junctions 2 and 3 there is direct current A plus line 4 and a minus line 5 are alternately connected.
Wie aus Fig. 5 zu ersehen, werden die Heizdrähte 1 zweckmäßig in einem Widerstandsträger 6 untergebracht, der aus einem wärmeleitenden Werkstoff besteht und infolge seines schwalbenschwanzförmigen Querschnittes einen festen Halt in der Platte 7 der Vorrichtung besitzt. As can be seen from Fig. 5, the heating wires 1 are expediently in housed a resistance carrier 6, which is made of a thermally conductive material exists and a firm hold due to its dovetail-shaped cross-section in the plate 7 of the device.
Die Fig. 6 zeigt Heizplatten 7 in Arbeitslage übereinander mit dazwischenliegenden Werkstoffbahnen 8. Fig. 6 shows heating plates 7 in the working position one above the other with intervening Material webs 8.
In der mittleren Heizplatte sind die Widerstände so eingesetzt, daß sie sowohl die darüberliegende als auch die darunter befindliche Werkstoffbahn 8 beheizen. Während die mittlere Heizplatte 7 beidseitig wirkt, beheizen die obere und untere Platte 7 nur einseitig die anliegende Kunststoffbahn.In the middle heating plate the resistors are inserted so that they both the overlying and the underlying web of material 8 heat. While the middle heating plate 7 works on both sides, the upper one heats and lower plate 7 only on one side the adjacent plastic sheet.
In Fig. 7 ist ein Querschnitt durch eine Heizvorrichtung gezeigt, deren Heizdraht 1 in dem angegebenen Bereich 9 auf die unter der Vorrichtung liegende Werkstofbahn wirksam ist. Der Heizdraht 1 ist in einer nicht ebenen Fläche verlegt, so daß eine Seite der Heizdrahtstücke nicht mit der Werkstoffbahn in Berührung kommt, sondern nur dazu dient, über die Klemmschrauben 10 an eine elektrische Leitung angeschlossen zu werden. Unterhalb des höherliegenden Teiles der Heizdrahtstücke ist ein der Krümmung derselben angepaßter Isolationskörper 11 vorgesehen, der auch die Köpfe der Klemmschrauben 10 in ihrer Lage festhält, so daß ein Verdrehen dieser Schrauben nicht möglich ist. In Fig. 7 a cross section through a heating device is shown, their heating wire 1 in the specified area 9 on the one below the device Material web is effective. The heating wire 1 is laid in a non-level surface, so that one side of the heating wire pieces does not come into contact with the material web, but only serves to be connected to an electrical line via the clamping screws 10 to become. Below the higher part of the heating wire pieces is one of the curvatures the same adapted insulation body 11 is provided, which also the heads of the clamping screws 10 holds in place so that turning these screws is not possible.
Statt nur nach einer Seite kann der flach gewickelte Widerstand auch nach beiden Seiten abgesetzt sein. Instead of just one side, the flat-wound resistor can also be used be offset on both sides.
Dementsprechend sind dann auch die Isolierkörper 11 doppelt vorgesehen.Accordingly, the insulating bodies 11 are then also provided twice.
Fig. 8 zeigt ein Ausführungsbeispiel einer aus miteinander verbundenen Heizdrahtstücken 1 zusammengesetzten flachen Heizwicklung, bei der die Verbindungsstellen 2 und 3 jeweils an einer Seite der Wicklung in einem abgeflachten Schlaufenteil vorgesehen sind. Fig. 8 shows an embodiment of an interconnected Heating wire pieces 1 assembled flat heating winding, in which the connection points 2 and 3 each on one side of the winding in a flattened loop part are provided.
Fig. 9 stellt eine Heizvorrichtung im Querschnitt dar, bei der die flach gewickelte Heizspirale 1 vertikal in eine isolierte Nut 12 eingesetzt ist. Der Heizstrom wird über Klemmschrauben 13 zugeführt, die in Isolationsmuffen 14 eingeschraubt sind. Als Schweißfläche wird hierbei etwa die halbe Oberfläche der unteren Drähte verwendet, so daß sich schmale Schweißnähte ergeben. Die einzelnen Bögen der Heizspirale können mit Isolationsmasse ausgefüllt werden. Fig. 9 shows a heater in cross section, in which the Flat wound heating coil 1 is inserted vertically into an insulated groove 12. The heating current is supplied via clamping screws 13 which are inserted into insulation sleeves 14 are screwed in. About half the surface of the lower Wires are used so that there are narrow welds. The individual arches the heating coil can be filled with insulation compound.
Bei dieser Vorrichtung werden zweckmäßig Heizdrahtstücke nach Fig. 8 verwendet, deren untere Bögen einen möglichst breiten geraden Teil aufweisen.In this device, heating wire pieces according to Fig. 8 used, the lower arches have as wide a straight part as possible.
Fig. 10 veranschaulicht eine Heizvorrichtung, die, ähnlich wie die Heizvorrichtung nach Fig. 9, entsprechend der Schweißfläche 15 nur eine schmale Schweißnaht erzeugt. Die Heizspirale ist in zwei Isolationskörpern 16 und 17 eingebettet und über Klemmschrauben 13 an elektrische Leitungen angeschlossen. FIG. 10 illustrates a heating device which, similar to that of FIG Heating device according to FIG. 9, corresponding to the welding surface 15, only a narrow one Weld seam generated. The heating coil is embedded in two insulation bodies 16 and 17 and connected to electrical lines via clamping screws 13.
Fig. 11 zeigt eine weitere Ausführungsform einer flachen Heizspirale, die abgewinkelt zwischen Isolierkörpern 18 und 19 eingesetzt ist und von seitlichen Klemmschrauben 20 aus mit Strom versorgt wird. Eine schwalbenschwanzförmige Nut 21 gibt dem die breite Schweißfläche 9 bildenden Teil der Heizwicklung festen Halt; außerdem dient ein bogenförmigerVorsprung 22 des Isolierkörpers 18 ebenfalls dazu, den die Heizfläche darstellenden Teil der Wicklung festzuhalten. 11 shows a further embodiment of a flat heating coil, which is angled between the insulators 18 and 19 and inserted from the side Terminal screws 20 is powered off. A dovetail groove 21 gives the part of the heating coil that forms the wide welding surface 9 a firm hold; In addition, an arcuate projection 22 of the insulating body 18 also serves to to hold the part of the winding that represents the heating surface.
Claims (8)
Priority Applications (1)
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DEF22287A DE1134195B (en) | 1957-02-06 | 1957-02-06 | Device for welding plastics, in particular plastic films |
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DEF22287A DE1134195B (en) | 1957-02-06 | 1957-02-06 | Device for welding plastics, in particular plastic films |
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DE1134195B true DE1134195B (en) | 1962-08-02 |
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DEF22287A Pending DE1134195B (en) | 1957-02-06 | 1957-02-06 | Device for welding plastics, in particular plastic films |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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DE3936218A1 (en) * | 1989-10-31 | 1991-05-02 | Pkm Kunststoffverarbeitungsmas | Welding thermoplastic foils - by contour electrode urging them on a heating element |
US20170282479A1 (en) * | 2016-03-30 | 2017-10-05 | Pregis Innovative Packaging Llc | Heat sealer |
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CH181985A (en) * | 1935-04-09 | 1936-01-31 | Hofer Hans | Process for the production of electric heating elements. |
CH224603A (en) * | 1938-12-12 | 1942-12-15 | Gen Electric Co Ltd | Electric heater. |
US2455186A (en) * | 1946-11-02 | 1948-11-30 | Gen Motors Corp | Domestic electric heater |
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CH181985A (en) * | 1935-04-09 | 1936-01-31 | Hofer Hans | Process for the production of electric heating elements. |
CH224603A (en) * | 1938-12-12 | 1942-12-15 | Gen Electric Co Ltd | Electric heater. |
US2455186A (en) * | 1946-11-02 | 1948-11-30 | Gen Motors Corp | Domestic electric heater |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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DE3936218A1 (en) * | 1989-10-31 | 1991-05-02 | Pkm Kunststoffverarbeitungsmas | Welding thermoplastic foils - by contour electrode urging them on a heating element |
US20170282479A1 (en) * | 2016-03-30 | 2017-10-05 | Pregis Innovative Packaging Llc | Heat sealer |
US10967600B2 (en) * | 2016-03-30 | 2021-04-06 | Pregis Innovative Packaging Llc | Protective packaging longitudinal heat sealer |
US11524475B2 (en) | 2016-03-30 | 2022-12-13 | Pregis Innovative Packaging Llc | Protective packaging longitudinal heat sealer |
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