Method and device for separating two bonded component parts made of plastic

Abstract

The invention relates to a method and a device (1) for separating component parts (2, 3) which are made of plastic and are bonded together along a boundary surface (7). Laser radiation (10) is emitted onto the boundary surface (7) in order to soften, in particular melt, at least plastic material of one of the component parts (2, 3) along the boundary surface (7), and a separating force (F) is applied to the component parts (2, 3) in order to separate the component parts (2, 3) along the softened plastic material.

Description

[0001] Method and device for separating two materially bonded plastic components

[0002] The content of the German patent application DE 10 2023 207 194.0 is incorporated herein by reference.

[0003] The invention relates to a method for separating two plastic components that are integrally connected along an interface. The components to be separated can, in particular, be welded to one another, for example, by laser welding. The invention also relates to a device for separating two component components that are integrally connected along an interface.

[0004] Plastic components have a wide range of uses. Functional components in particular combine various plastic components. Bonded joints, for example, through welding or multi-component injection molding, have proven to be economical and stable. However, it is difficult to separate bonded components. Therefore, it is often necessary to separate components made of different plastic materials into separate material types, for example, for recycling purposes or in the event of take-back obligations. In many cases, the components serve as housings for the functional parts stored within, such as battery cells and / or electronic components. Opening the plastic components, for example, for recycling or repair, regularly carries the risk of damaging the often expensive functional parts.

[0005] It is therefore the object of the present invention to provide a method for separating materially bonded component parts made of plastic, with which the component parts can be separated in a particularly simple and gentle manner.

[0006] This object is achieved by the method according to claim 1. This object is also achieved by the device having the features specified in claim 16. Advantageous embodiments are the subject of the subclaims.

[0007] The method according to the invention for separating two plastic components that are materially joined along an interface comprises the following steps:

[0008] Irradiating laser radiation onto the interface to soften at least plastic material of one of the component parts along the interface and

[0009] Applying a separating force to the component parts to separate the component parts along the softened plastic material.

[0010] The core of the process is that the plastic material of at least one of the component parts is first softened, in particular melted, along the interface. The applied separation force allows the component parts to be separated easily, precisely, and gently along the softened, in particular melted, plastic material. By directing the laser radiation onto the interface, the separation area is precisely predefined. Separating the softened, in particular melted, plastic material is possible with minimal force, thus avoiding damage to the component parts to be separated and / or other components of the component. In particular, breakage of the component parts is avoided.

[0011] A particular advantage of the process is that the component parts can be precisely separated. This allows for the separate recycling of the respective plastic materials, particularly when components are made of different plastic materials.

[0012] The gentle separation of the component parts also has the advantage that other components of the component, in particular functional parts encased in the component parts to be separated, such as electronic components and / or battery cells, are not damaged. This allows the functional parts to be reused, repaired, replaced, and / or disposed of separately. Particularly advantageously, the separated component parts can be rejoined, for example, by rewelding, after the gentle separation. This makes it possible, for example, to replace and / or repair encased functional parts. This can reduce scrap in the production of encased functional parts.

[0013] The component parts to be separated are integrally connected along an interface. The component parts can, for example, have been manufactured together, for example by multi-component injection molding. The component parts can also be manufactured separately and then connected to one another, for example by welding. For example, the component parts can be connected to one another along the interface by friction welding and / or laser welding. The interface can, for example, be in the form of a connecting contour, in particular a closed contour. The interface can, for example, be a seam, in particular a weld seam, along which the components are connected, in particular welded. The interface, in particular the seam, has, for example, a width of between 0.3 mm and 5 mm. The laser radiation is preferably irradiated only in the region of the interface.

[0014] The component parts consist of a plastic material, preferably of different plastic materials. Preferably, at least one of the component parts is made of a thermoplastic. Particularly preferably, both component parts are made of thermoplastic. This facilitates the softening, in particular melting, of the plastic material along the interface. Suitable thermoplastics include, for example, polyamide (PA), polyethylene terephthalate (PET), blends of acrylonitrile butadiene styrene and polycarbonate (ABS + PC), polybutylene terephthalate (PBT), and / or polypropylene (PP). ABS + PC, for example, is increasingly used in medical technology, while PBT and PP are used in the automotive industry.

[0015] With the help of the irradiated laser radiation, at least the plastic material of one of the two components, in particular the plastic material of both component components, is softened, preferably melted, along the interface. The irradiated laser radiation heats the plastic material, causing it to soften. For example, the plastic material of at least one of the component components can be heated above a softening temperature. Suitable measures for the softening temperature are, for example, the heat deflection temperature (HDT) and the Vicat softening temperature (VIST). HDT can be measured in particular according to DIN EN ISO 75-1, -2, -3. VIST can be measured in particular according to DIN EN ISO 306.

[0016] Preferably, at least the plastic material of one of the component parts, in particular the plastic material of both component parts, is melted, in particular by heating the plastic material along the interface above the respective melting temperature. The applied separation force allows the component parts to be separated along the molten plastic material.

[0017] Laser radiation of any wavelength can be used, in particular laser radiation with wavelengths that have proven effective for processing the respective plastic materials, for example in laser welding. Laser radiation in the visible and / or infrared range is particularly suitable. The laser radiation can, for example, have wavelengths between 400 nm and 2,500 nm. A spot diameter of the laser radiation can preferably be adapted to a width of the interface, in particular to the width of a seam, for example a weld seam. The laser power can be selected, in particular, depending on the plastic materials used, a desired irradiation duration, and / or a contour length of the interface, for example between 50 W and 400 W, in particular between 50 W and 200 W, for example between 50 W and 100 W.

[0018] The application of a separating force within the meaning of the present method is understood to mean the application of a force designed to separate the component parts from one another. For example, one of the component parts can be subjected to a force directed away from the other component part. The other component part can be held in position, for example, by means of a component holder, or can also be subjected to an opposing force. The separating force can be applied, in particular, mechanically, pneumatically, and / or hydraulically.

[0019] According to a preferred aspect of the method, the plastic material is heated along the interface by means of the irradiated laser radiation above its melting temperature but below its decomposition temperature. This enables reliable melting of the plastic material of at least one of the component parts without decomposing the plastic material. Material loss, in particular destruction of the plastic material, is also avoided along the interface. This improves the recyclability and / or reusability of the separated component parts. Furthermore, the energy input is reduced, which improves the efficiency of the method.

[0020] According to a preferred aspect of the method, the component parts consist of different plastic materials, which in particular have different transmission properties for the laser radiation. The separation of component parts made of different plastic materials is particularly advantageous for the pure recycling of the plastic materials. Different transmission properties enable the targeted irradiation and absorption of the laser radiation on the interface between the component parts in a particularly advantageous manner. Particularly preferably, the respective plastic materials of the component parts have overlapping melting point ranges. In particular, the melting temperatures of the respective plastic materials are close to one another, differing, for example, by a maximum of 50 °C, in particular by a maximum of 25 °C.This simplifies the softening, in particular melting, of the plastic materials of both component parts by irradiating them with laser radiation.

[0021] For example, the plastic materials of the component parts can be based on a common base material, which, however, contains different additives in the respective component parts. For example, the absorption behavior of the plastic material for the laser radiation can be adjusted using specific additives. In particular, one of the component parts can contain additives in the plastic material that promote the absorption of the laser radiation, for example, soot particles. Particularly suitable base materials are thermoplastics, for example, polyamide (PA), polyethylene terephthalate (PET), blends of acrylonitrile butadiene styrene and polycarbonate (ABS + PC), polybutylene terephthalate (PBT), and / or polypropylene (PP).

[0022] According to a preferred aspect of the method, one of the component parts is transparent to the laser radiation, and the laser radiation is irradiated through the transparent component part onto the interface. Particularly preferably, the other component part is highly absorbent for the laser radiation. Irradiation through the transparent component surface ensures that the laser radiation interacts with the plastic material of the component part essentially only in the area of ​​the interface. Separation can be carried out particularly precisely along the interface. This variant of the method can be used particularly easily and efficiently on laser-welded components. However, it is also possible to use other material-bonded component parts with corresponding transmission or absorption properties.

[0023] According to a preferred aspect of the method, the component parts to be separated are directly bonded to one another. Additional binders or connecting layers, for example, adhesives or adhesive films, are not arranged between the component parts. Component parts bonded in this way are difficult to separate, so that the present method can be used particularly advantageously with such components. In particular, the component parts cannot be separated by dissolving and / or softening the binder, for example, the adhesive. At the same time, any influence of the binder on the softening, in particular melting, of the plastic material of at least one of the component parts with the aid of the laser radiation is excluded.

[0024] According to a preferred aspect of the method, the component parts to be separated were joined together in a material-to-material bond by means of multi-component injection molding or plastic welding, in particular by means of laser welding. This allows the component parts to be joined directly to one another in a particularly reliable manner. Component parts joined in this way are particularly difficult to separate, so that the present method can be used particularly advantageously for such components. During plastic welding and / or multi-component injection molding, defined interfaces form between the component parts without the need for an additional binding agent, for example an adhesive. The component parts therefore cannot be separated by dissolving and / or softening the binding agent, for example the adhesive.At the same time, any influence of the binder on the softening, in particular melting, of the plastic material of at least one of the component parts with the aid of laser radiation is excluded.

[0025] According to a preferred aspect of the method, the plastic material of both component parts is softened, in particular melted, by means of the irradiated laser radiation. This ensures a particularly gentle separation of the component parts, in particular without damaging either component part. In particular, directly connected component parts, for example, welded component parts, can be reliably separated.

[0026] According to a preferred aspect of the method, the laser radiation is irradiated simultaneously or quasi-simultaneously onto the interface. This enables uniform and simultaneous softening, in particular melting, of the plastic material along the interface. Component distortion is avoided. Particularly preferably, the laser radiation is irradiated quasi-simultaneously using a laser scanner, for example a so-called galvo scanner. For example, the interface can be scanned once or several times with at least one laser beam, in particular with a laser beam feed rate between 100 mm / sec and 5,000 mm / sec, in particular between 500 mm / sec and 5,000 mm / sec. According to a preferred aspect of the method, the irradiation of the laser radiation and the application of the separating force occur with a temporal overlap, in particular parallel to one another. This ensures efficient separation of the component components.For example, if the separation force is applied in parallel, the component parts can be separated precisely when the plastic material along the interface has softened sufficiently, or in particular, melted sufficiently. This prevents excessive softening, or in particular melting, of the plastic material. The process is energy-efficient.

[0027] Preferably, the separation force is applied staggered in time after the start of laser radiation. In particular, the separation force is only applied when the plastic material of at least one of the component components, in particular the plastic material of both component components, has already softened to a certain degree. This prevents the separation process from starting too early and thus, in particular, the formation of plastic threads. Such plastic threads can lead to contamination of the component components or functional parts stored therein. In addition, the interfaces, in particular welding webs, would be damaged, thus impairing subsequent reuse of the component components.

[0028] The time delay between the start of laser radiation and the application of the separation force can be selected depending on the specific plastic materials and / or the laser power used. For example, the temperature of the plastic material along the interface can be used as a control parameter for applying the separation force. The temperature can be selected, for example, depending on the properties of the specific plastic materials.

[0029] It is also possible to separate the irradiation of the laser radiation and the application of the separating force in time. For example, the separating force can only be applied after the irradiation has ended. This is advantageous, for example, if the separating force is applied using suitable gripping tools, for example using suitable linear axis systems and / or suitable robotics, which could interfere with the beam path of the laser radiation to be irradiated. It is particularly advantageous to apply the separating force shortly after the end of the irradiation in order to reduce, and in particular to avoid, any interim cooling and thus hardening of the plastic material. For example, there can be a maximum time interval of 30 s between the end of the irradiation of the laser radiation and the application of the separating force.

[0030] According to a preferred aspect of the method, the separation force is applied essentially perpendicularly to a plane spanned by the interface. This enables a particularly efficient use of the separation force.

[0031] According to a preferred aspect of the method, the separation force is applied substantially uniformly along the entire interface. This enables uniform and efficient separation of the component parts. Excessive stress on individual areas of the component parts is avoided. For example, the separation force along the interface can deviate by a maximum of 50%, in particular by a maximum of 25%, of a maximum value.

[0032] Alternatively, it is also possible to vary the separation force along the interface, particularly by applying the separation force locally. This allows the component components to be separated locally with minimal force. For example, the component components can be separated successively along the interface by applying local forces. It is also possible to utilize the inherent rigidity of at least one of the component components to ensure a uniform force application along the interface, even with local separation forces.

[0033] According to a preferred aspect of the method, an overpressure is generated in an interior space formed between the component parts to apply the separating force. This enables a particularly uniform and gentle penetration of the separating force into the component parts. External damage to the component parts due to the application of mechanical force is avoided. Generating an overpressure is particularly suitable for separating component parts that form a housing, for example, for functional parts to be housed therein. For example, welded housings, especially laser-welded ones, can be easily separated this way.

[0034] The overpressure can be selected depending on the required separation force. In particular, the overpressure can be selected such that functional parts housed in the components to be separated are not damaged. The overpressure can be selected, in particular, depending on the geometry of the components. The overpressure can, for example, be between 0.1 bar and 20 bar, in particular between 0.5 bar and 10 bar, in particular between 0.5 bar and 2 bar, in particular approximately 1 bar.

[0035] The overpressure can be generated, for example, via a pressure connection in the interior. For example, an opening for the pressure connection can be provided in one of the component parts. It is also possible to create a corresponding opening in one or both component parts in a preparatory step, for example, by providing at least one of the component parts with a corresponding bore.

[0036] According to a preferred aspect of the method, the separating force is applied at least partially mechanically, in particular by means of a gripping tool, for example by means of a robotic gripping tool and / or a linear axis system with one or more linear axes. For example, at least one of the component parts to be separated can be gripped with the aid of a gripping tool in order to apply a mechanical force, in particular a tensile force, to it. For example, the component can be gripped and subjected to force with the aid of a vacuum gripper and / or suction cup. Alternatively or additionally, tool engagement can take place via engagement points on at least one of the component parts. Particularly suitable engagement points can be formed by undercuts in one component part, in both component parts, or between the component parts, in particular in the region of the interface.For example, a tensile force can be exerted on one of the component parts via the tool engagement. Additionally or alternatively, the tool can be inserted between the component parts, thereby cutting through the softened, particularly molten, plastic material in the area of ​​the interface.

[0037] According to a preferred aspect of the method, the components to be separated form a housing enclosing an interior space, wherein the laser radiation is irradiated in such a way that no laser radiation enters the interior space. This ensures that the laser radiation does not impair or damage functional components located in the interior space, such as battery cells or electronic components. The incidence of the laser radiation into the interior space can be achieved, for example, by a suitable selection of the beam guidance, beam dimensions, and / or beam shading.

[0038] Particularly preferably, the separating force is applied in such a way that functional components located inside the housing are not affected. For example, it can be ensured that the separating force only acts on the outside of the component parts.

[0039] According to a preferred aspect of the method, at least one of the separated component parts is rejoined, in particular welded, to a component part along the interface. Particularly preferably, both previously separated component parts are rejoined, in particular welded. The separated component parts can be reused, which is environmentally friendly and economical. For example, remnants of a welding web in the region of the interface can be used for this purpose. It is also possible to provide additional welding webs to enable the component parts to be rejoined after they have been separated. A component having the component parts integrally bonded along the interface is preferably designed such that the component parts can be easily separated using the method described above.Particularly preferably, the component is designed such that at least one of the component components can be rejoined, in particular rewelded, after separation. For example, the component or its component components can have one or more of the following properties:

[0040] At least one of the component components is made of a thermoplastic material. Preferably, both component components are made of thermoplastic material.

[0041] The component parts are made of different plastic materials, whereby the different plastic materials preferably have overlapping melting point ranges.

[0042] One of the component parts is transparent to laser radiation, in particular to laser radiation with wavelengths between 400 nm and 2500 nm, so that the laser radiation can be irradiated through the transparent component part onto the interface. The thickness of the transparent component in the regions to be irradiated is preferably between 200 pm and 5 mm. Particularly preferably, the thickness of the transparent component in the region to be irradiated is essentially constant, in particular the thickness fluctuates by a maximum of a factor of 2. The thickness of the transparent component is in particular dimensioned such to enable the transparent component to be rejoined. For example, the thickness of the transparent component can be selected such that it is at least twice the thickness of a weld nugget created when the plastic material is melted.

[0043] One of the component parts is absorbent for the laser radiation, in particular for laser radiation with wavelengths between 400 nm and 2500 nm. In particular, the absorbing component part has a defined optical penetration depth for the laser radiation, preferably between 10 pm and 500 pm.

[0044] The interface along which the two component parts are firmly bonded forms a closed contour, particularly in the form of a seam, such as a weld seam. The contour preferably has a width between 0.2 mm and 5 mm.

[0045] Areas of the interfaces on opposite sides of the component parts have an angle between 0° and 120° to each other.

[0046] At least one of the component parts has engagement points that enable a targeted application of a separating force, in particular perpendicular to a plane in which the interface runs. For example, engagement points can be formed by undercuts into which gripping tools can engage. In the case of welded component parts, in particular laser-welded component parts, a welding web can be dimensioned such that it enables multiple welding. For example, at least one of the materially bonded component parts can have a residual welding web that enables re-welding of this component part after the separation of the component parts. The height of a residual welding web can, for example, be at least 0.05 mm, in particular between 0.05 mm and 0.7 mm.Additionally or alternatively, several welding bars may be present which are used for welding in the respective joining processes.

[0047] The design of a component from materially connected component components according to one or more of the above-mentioned features represents an independent aspect of the invention described here.

[0048] The device according to the invention for separating two plastic component parts that are materially joined along an interface comprises an irradiation device for irradiating laser radiation onto the interface to soften at least plastic material of one of the component parts along the interface, and a force application device for applying a separating force to the component parts to separate the component parts along the softened plastic material. The device is particularly suitable for carrying out the method described above. The advantages and optional features of the device correspond to those described above with regard to the method. The device can, in particular, comprise a holding device for holding the component, in particular one of the component parts.For example, the device may comprise a component receptacle for placing and holding the component and / or one of its component parts therein.

[0049] The device can, in particular, comprise a protective device for protecting the irradiation device from damage caused by the components to be separated. For example, a shielding device transparent to the laser radiation, for example in the form of a glass plate, can be arranged between the irradiation device and the components to be separated, in particular a component holder for this purpose.

[0050] According to a preferred aspect of the device, the irradiation device comprises a laser scanner for scanning the interface once or repeatedly with the laser radiation, in particular for quasi-simultaneous irradiation of the laser radiation onto the interface. The laser scanner can be, for example, a galvo scanner.

[0051] According to a preferred aspect of the device, the force application device comprises a pressure device for generating overpressure in an interior space between the component parts to be separated. The pressure device can, in particular, comprise a compressed air connection and / or a compressed air generator.

[0052] According to a preferred aspect of the device, the force application device comprises a gripping tool for gripping one of the component parts and for exerting a mechanical force thereon. The gripping tool can be designed, in particular, to exert a tensile force on one of the component parts. For example, the gripping tool can comprise a vacuum gripper or a suction cup. Alternatively or additionally, the gripping tool can comprise a tool that grips into engagement points, in particular undercuts, formed in one of the component parts or between the component parts. The gripping tool can also promote the separation of softened, in particular molten, plastic material, for example, by the gripping tool being insertable into the softened, in particular molten, plastic material in the region of the interface.The gripping tool may comprise a displacement device, for example a robotic arm and / or a linear axis system with one or more linear axes.

[0053] Further features, details, and advantages of the invention will become apparent from the following description of several embodiments with reference to the accompanying drawings. They show:

[0054] Fig. 1 shows a schematic cross-section through a device for separating component parts made of plastic that are bonded together along an interface,

[0055] Fig. 2 schematically shows another embodiment of a device for separating the component parts and

[0056] Fig. 3 schematically shows another embodiment of a device for separating the component parts. Corresponding parts are provided with the same reference numerals in Figs. 1 to 3. Details of the embodiments explained in more detail below may also constitute an invention in themselves or be part of a subject matter of the invention.

[0057] Fig. 1 schematically shows an embodiment of a device 1 for separating integrally connected component parts 2, 3. The component parts 2, 3 form a component 4, which is placed in a component holder 5 of the device 1. Fig. 1 shows a longitudinal section through the component 4 and the component holder 5.

[0058] Components 2, 3 form a housing enclosing an interior space 6. Functional components not shown, in particular battery cells or electronic components, can be arranged in the interior space 6. In the illustrated embodiment, component 3 serves as the housing base, and component 2 serves as the cover.

[0059] The component parts 2, 3 are firmly bonded along a circumferential interface 7. In the illustrated embodiment, the component parts 2, 3 are welded by plastic welding, in particular by laser welding. The interface 7 forms a weld seam. A residual weld land 8 of the component part 3 is present in the area of ​​the weld seam. The weld seam has a width of, for example, between 0.3 mm and 5 mm.

[0060] The device 1 has an irradiation device 9 for irradiating laser radiation 10 onto the interface 7. The irradiation device 9 has a laser scanner 11 in the form of a galvo scanner for the targeted irradiation of the laser radiation 10. The laser radiation 10 can, for example, have a wavelength between 400 nm and 2,500 nm, in particular a wavelength in the infrared range. A spot diameter of the laser radiation 10 is preferably adapted to the width of the interface 7. The laser power, depending on the plastic materials of the component parts 2, 3, the desired irradiation duration, and / or the contour length of the interface 7, is, for example, between 50 W and 400 W, in particular between 50 W and 200 W, for example between 50 W and 100 W.

[0061] The component parts 2, 3 are made of different thermoplastic materials that have different transmission properties for the laser radiation 10. Component part 2 is transparent to the laser radiation 10. Component part 3 absorbs the laser radiation 10.

[0062] The device 1 has a force application device 12 for applying a separating force to the component parts 2, 3. The force application device 12 has a pressure device 13 for generating overpressure in the interior space 6. For this purpose, the pressure device 13 is fluidly connected to the interior space 6 via a pressure connection 14 formed in the component holder 5 and an opening 15 in the component part 3. The opening 15 can be provided as an integral part of the component part 3 during its manufacture. It is also possible to introduce the opening 15 for separating the component parts 2, 3 into the component part 3, for example, in a preparatory step. For example, the opening 15 can be introduced as a bore in the component part 3. To separate the component parts 2, 3, the laser radiation 10 is irradiated through the transparent component part 2 onto the interface 7 with the aid of the irradiation device 9.In the illustrated embodiment, the irradiation occurs quasi-simultaneously. The laser radiation 10 is absorbed in the component 3 and heats the plastic materials of the components 2, 3. The quasi-simultaneous irradiation results in homogeneous and simultaneous heating along the interface 7.

[0063] The laser radiation 10 is irradiated onto the interface 7 in such a way that the laser radiation 10 is prevented from irradiating the interior 6. This prevents any interaction of the laser radiation 10 with any sensitive functional components in the interior 6. Damage to the functional components by the laser radiation 10 is excluded.

[0064] The power of the laser radiation 10 and the irradiation duration are dimensioned such that the plastic material of at least component 3 is heated to a temperature above its melting temperature. However, the plastic material is not heated to its decomposition temperature. The plastic material of at least component 3 is melted by the laser radiation 10. Preferably, the plastic material of both component components 2, 3 is melted along the interface 7. Particularly preferably, the melting point ranges of the plastic materials of component components 2, 3 overlap.

[0065] Parallel to the irradiation of the laser radiation 10, the pressure in the interior space 6 is increased via the force application device 12. For example, an overpressure of approximately 1 bar is generated in the interior space 6. This overpressure creates a separation force F. The separation force F acts on the component 2 in the direction of the arrow shown in Fig. 1. The generation of the separation force F by means of overpressure ensures a uniform application of the separation force along the interface 7.

[0066] Due to the applied separation force F, component 2 separates from component 3 along the molten plastic material. Components 2, 3 are thereby gently and precisely separated along the interface 7. Any other damage to components 2, 3 or any functional parts arranged in the interior 6 is avoided. Components 2, 3 and any functional parts can be recycled, repaired, and / or reused separately.

[0067] In particular, it is possible to reuse at least one of the component parts 2, 3. For example, the component parts 2, 3 can be joined again along the interface. For this purpose, the residual welding web 8 can be used, for example. The residual welding web 8 can be dimensioned such that it enables the component part 3 to be welded again to the component part 2 or to another suitable component part. For example, the residual welding web 8 can have a height of at least 0.05 mm. It is also possible to provide the component parts 2, 3, in particular the component part 3, with an additional welding web that was not used in the first welding process. The additional welding web can then be used to rejoin the component part 3 after it has been separated. Fig. 2 shows a further embodiment of a device 1a for separating the component parts 2, 3.The device 1a differs from the device 1 according to Fig. 1 only in the force application device 12a. The force application device 12a has a gripping tool 16 for gripping the component 2. The gripping tool 16 has a robotic arm 17, which enables displacement in the transverse direction t and in the vertical direction v. At the end of the robotic arm 17, a vacuum gripper 18 is arranged for gripping the component 2. By displacing the vacuum gripper 18 with the aid of the robotic arm 17, in particular in the vertical direction v, the separating force F can be exerted on the component 2.

[0068] In other embodiments, a suction cup may be present instead of a vacuum gripper 18. Other configurations of the robotic arm are also possible, for example, configurations that allow displacement in only one direction. In addition to or as an alternative to the robotic arm, other displacement devices may also be used, for example, linear axis systems with one or more linear axes.

[0069] The force application device 12a enables gripping and exerting a mechanical force on the component parts 2, 3 without the component parts having to be specially designed.

[0070] In the embodiment shown in Fig. 2, no pressure device is present. The component holder 5a therefore has no pressure connection. However, it is also possible to combine the gripping tool 16 with a corresponding pressure device. Fig. 3 shows a further embodiment of a device 1b for separating the component parts 2, 3. The device 1b differs from the previously discussed devices in the design of the force application device 12b. The force application device 12b has a gripping tool in the form of engagement tools 19, which engage in a groove 20 formed between the component parts 2, 3. The engagement tools 19 can apply the separating force F locally to the component parts 2, 3 at the engagement points along the interface 7.

[0071] In the illustrated embodiment, the engagement tools 19 are wedge-shaped. The component 2 can therefore be lifted by successively inserting the engagement tools 19 into the groove 20. This also facilitates the cutting of the molten plastic material in the area of ​​the interface.

[0072] In the embodiment shown in Fig. 3, the engagement tools 19 engage in a groove 20 formed between the component parts 2, 3. It is also possible to allow the engagement tools 19 to engage at suitable engagement points on one or both of the component parts 2, 3. For example, suitable projections and / or grooves can be provided in one or both of the component parts 2, 3.

[0073] In the embodiments shown in Figs. 1 to 3, each of the force application devices is shown. The force application devices can also be combined. For example, a mechanical force application can be combined with a pneumatic force application using overpressure.

Claims

Patent claims 1. A method for separating two component parts (2, 3) made of plastic which are connected by a material bond along an interface (7), comprising the steps Irradiating laser radiation (10) onto the interface (7) to soften at least plastic material of one of the component parts (2, 3) along the interface (7) and Applying a separating force (F) to the component parts (2, 3) to separate the component parts (2, 3) along the softened plastic material.

2. Method according to claim 1, characterized in that by means of the irradiated laser radiation (10) the plastic material is heated along the interface (7) above its melting temperature but below its decomposition temperature.

3. Method according to one of the preceding claims, characterized in that the component parts (2, 3) consist of different plastic materials which in particular have different transmission properties for the laser radiation (10).

4. Method according to claim 3, characterized in that one of the component parts (2) is transparent to the laser radiation (10) and that the laser radiation (10) is irradiated through the transparent component part (2) onto the interface (7).

5. Method according to one of the preceding claims, in particular according to claim 3 or 4, characterized in that the Components (2, 3) are directly connected to one another by a material fit.

6. Method according to one of the preceding claims, in particular according to claim 3 or 4, characterized in that the component parts (2, 3) to be separated were joined in a materially bonded manner by means of multi-component injection molding or plastic welding, in particular by means of laser welding.

7. Method according to one of the preceding claims, characterized in that the plastic material of both component parts (2, 3) is softened, in particular melted, by means of the irradiated laser radiation (10).

8. Method according to one of the preceding claims, characterized in that the laser radiation (10) is irradiated simultaneously or quasi-simultaneously onto the interface.

9. Method according to one of the preceding claims, characterized in that the irradiation of the laser radiation (10) and the introduction of the separating force (F) have a temporal overlap, in particular take place parallel to one another.

10. Method according to one of the preceding claims, characterized in that the separating force (F) is applied substantially perpendicularly to a plane spanned by the interface (7).

11. Method according to one of the preceding claims, characterized in that the separating force (F) is applied substantially uniformly along the entire interface (7).

12. Method according to one of the preceding claims, characterized in that in order to introduce the separating force (F), an overpressure is generated in an interior space (6) formed between the component parts (2, 3).

13. Method according to one of the preceding claims, characterized in that the separating force (F) is introduced at least partially mechanically, in particular by means of a gripping tool (16; 19).

14. Method according to one of the preceding claims, characterized in that the component parts (2, 3) to be separated form a housing enclosing an interior space (6) and the irradiation of the laser radiation (10) takes place in such a way that no laser radiation (10) is incident into the interior space (6).

15. Method according to one of the preceding claims, characterized in that at least one of the separated component parts (2, 3) is joined, in particular welded, to a component part again along the interface (7).

16. Device (1; 1a; 1b) for separating two component parts (2, 3) made of plastic that are connected by a material bond along an interface (7), comprising an irradiation device (9) for irradiating laser radiation (10) onto the interface (7) to soften at least Plastic material of one of the component parts (2, 3) along the interface (7) and a force application device (12; 12a; 12b) for applying a separating force (F) to the component parts (2, 3) to separate the component parts (2, 3) along the softened plastic material.

17. Device (1; 1a; 1b) according to claim 16, characterized in that the irradiation device (9) has a laser scanner (10) for scanning the interface (7) once or several times with the laser radiation (10), in particular for quasi-simultaneous irradiation of the laser radiation (10) onto the interface (7).

18. Device (1) according to one of claims 16 or 17, characterized in that the force application device (12) has a pressure device (13) for generating excess pressure in an interior space (6) between the component parts (2, 3) to be separated.

19. Device according to one of claims 16 to 18, characterized in that the force application device (12a; 12b) comprises a gripping tool (16; 19) for gripping one of the component parts (2, 3) and for exerting a mechanical force (F) thereon.

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