Grinding device

Abstract

The invention relates to a grinding device, in particular a manual grinding device, with a carrier unit (12a; 12b) comprising a carrier body (14a; 14b), in particular a carrier block, which consists at least largely of a foam, in particular an elastomeric foam, and with at least one abrasive grinding element (16a; 16b), in particular a grinding skin, arranged on at least one side of the carrier unit (12a; 12b), which is firmly connected to the carrier unit (12a; 12b). It is proposed that the carrier body (14a; 14b) consists at least partially of a composite foam.

Description

State of the art

[0001] A grinding device with a carrier unit having a carrier body, in particular a carrier block, which consists at least to a large extent of a foam, in particular an elastomeric foam, and with at least one abrasive grinding element, in particular a grinding skin, arranged on at least one side of the carrier unit and which is firmly connected to the carrier unit, has already been proposed. Disclosure of the invention

[0002] The invention relates to a grinding device, in particular a manual grinding device, with a carrier unit which has a carrier body, in particular a carrier block, which consists at least to a large extent of a foam, in particular an elastomeric foam, and with at least one abrasive grinding element, in particular a grinding skin, which is arranged on at least one side of the carrier unit and is firmly connected to the carrier unit.

[0003] It is proposed that the carrier body be made at least partially of a composite foam. Preferably, the carrier body has at least one layer of a composite foam. Preferably, the carrier body is made entirely of a composite foam.

[0004] The inventive design of the grinding device makes it possible to provide a particularly sustainable and environmentally friendly grinding device. In particular, it allows for an advantageously high proportion of recycled material. Furthermore, user comfort when using the grinding device in at least one application state can be increased. A further advantage of the invention is that a more sustainable material is used to produce foam for the grinding device. Furthermore, the development creates an opportunity for the recycling of PU foams, which is currently one of the requirements of the foam industry.

[0005] The sanding device is preferably sandpaper, a sanding pad, a sanding fleece, or a sanding block for manual use. In the application state, a user can use and / or employ the sanding device to sand at least one workpiece and / or component, such as pieces of furniture and / or everyday objects or the like. It would also be conceivable for the sanding device to be connectable to part of a sanding machine and / or to be fastened to the sanding machine. In the application state, the sanding device could be fastened to the sanding machine. In particular, the application state is at least a sanding state in which at least the workpiece and / or component can be processed, namely sanded, by means of the sanding device.

[0006] The grinding device is formed, in particular, by a manual grinding block. The grinding device is, in particular, block-shaped. For example, the grinding device can be rectangular or square, especially if the grinding device is a grinding block. The grinding device could also be a grinding sponge. If the grinding device is designed as sandpaper or abrasive fleece, the grinding device can be plate-shaped, at least in sections. It would also be conceivable for the grinding device to be a grinding fiber or grinding finger.The term "plate-like" is to be understood as a three-dimensional object which, viewed in a developed view in a plane, has a non-circular cross-sectional area viewed in a cross-section perpendicular to the plane and, perpendicular to the plane, apart from individual recesses, in particular through holes and / or blind holes or the like, has an at least substantially constant material thickness which amounts to less than 50%, preferably less than 25%, and particularly preferably less than 10% of a surface extension of the three-dimensional object parallel to the plane, in particular a smallest surface extension of the object parallel to the plane. Preferably, a material thickness of the plate-like object corresponds to a maximum of 50%, in particular a maximum of 20%, advantageously a maximum of 10%, preferably a maximum of 5%, of a longitudinal extension and / or a width extension of the object.Furthermore, it should be understood that at least the smallest possible geometric cuboid, which just completely encloses the object, is plate-like.

[0007] Furthermore, the grinding device has at least two opposing grinding surfaces, which are aligned parallel to a main extension plane of the grinding device. A "main extension plane" of a component, in particular of the grinding device, is understood to be a plane that is parallel to a largest side surface of a smallest imaginary cuboid that just completely encloses the component. Preferably, the grinding device has the abrasive grinding element. The abrasive grinding element forms, in particular, a grinding surface that is designed, at least in sections, as a flat surface. In particular, the grinding surface is aligned parallel to the main extension plane of the grinding device."Parallel" is understood here to mean an alignment of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction of less than 8°, advantageously less than 5° and particularly advantageously less than 2°.

[0008] The grinding surface can be provided for contacting the grinding device with the workpiece and / or component to be machined in the application state. Preferably, the plurality of abrasive grains are arranged on the working contact surface or form it.

[0009] The carrier unit serves in particular to support the grinding element. The carrier unit comprises in particular the carrier body, which in particular forms a base body of the grinding device. The carrier body preferably occupies a large part of the volume of the grinding device. The composite foam is created in particular from the recyclable residues that arise during the processing of PU foams. Foam flakes or resulting foam residues are collected and reprocessed with various other additives that influence the properties of the composite foam. The materials to be processed are pressed and glued. The polymeric foam carrier is often made from polyurethane foams (PU foams). In an effort to deliver a more sustainable product, the new foam material is replaced with reglued foams.Rebonded foam, particularly composite foam, is produced by shredding / granulating waste material from foam production and / or discarded or used foam products. The particulate material is mixed with an adhesive, such as nitrile, PU, ​​phenol, and others, compacted to the desired density, and cured into master blocks. These master blocks can be converted into strips for production. The composite foam is preferably PU-based. However, other foams deemed appropriate by a person skilled in the art are also conceivable. The composite foam in particular has a density of 60-300 kg / m². The composite foam can also have a hardness of 6-120 kPa at 40% compression. Ideally, the compression hardness is in the range of 10-40 kPa.

[0010] It is further proposed that the grinding element at least substantially completely encompasses the carrier body in at least one plane. The grinding element is preferably configured to extend circumferentially in a plane perpendicular to a main direction of extension of the grinding device. The grinding element is preferably arranged on at least four sides of the carrier unit, in particular of the carrier body. The grinding element preferably covers four sides of the carrier unit. However, it would also be conceivable for the grinding element to be arranged on only three sides of the carrier unit. A "main direction of extension" of an object is to be understood in particular as a direction that runs parallel to a longest edge of a smallest geometric cuboid that just completely encloses the object. This allows the use of a grinding device that is advantageously versatile.Preferably, the grinding device is formed by a grinding block.

[0011] It is further proposed that the abrasive element comprise at least one support layer, in particular a base binder, made of a TPU adhesive and abrasive grains located at least partially in the support layer, in particular the base binder. In particular, the plurality of abrasive grains are conceivable as grain materials of natural and / or synthetic origin. The abrasive grains can, for example, consist at least largely of a mineral, such as flint, quartz, sand, garnet, natural diamond, and / or corundum, silicon carbides, silicon oxide, aluminum oxide, chromium oxides, cubic boron nitride, and / or a composite material. This makes it possible, in particular, to provide an advantageous abrasive element.

[0012] It is further proposed that the abrasive element be firmly bonded to the carrier unit via the supporting layer made of TPU adhesive. The TPU adhesive is formed, in particular, by a hot-melt film and / or a hot-melt adhesive that is applied to the carrier body by coating. Both reactive and non-reactive adhesives can be used. TPU-based adhesives are preferred. However, adhesives with polyolefin-based, polyester, or polyamide materials are also conceivable as alternatives. High-melting adhesives with a temperature of >140°C are preferred. The weight of the coating of the abrasive element is in particular in the range of 80-300 g / m², preferably 140-180 g / m². "Heavy-duty bonded" is to be understood, in particular, as meaning that the mass components are held together by atomic or molecular forces, such as during soldering, welding, gluing, and / or vulcanization.This makes it possible to provide, in particular, an advantageous grinding element. In particular, it is possible to provide an advantageous one-piece grinding device. "One-piece" is understood to mean, in particular, at least materially connected, for example, by a welding process, an adhesive process, an injection molding process, and / or another process deemed appropriate by a person skilled in the art, and / or advantageously formed in one piece, such as by production from a single casting and / or by production using a single- or multi-component injection molding process, and advantageously from a single blank.

[0013] It is further proposed that the carrier unit have at least one compensating foam layer arranged on at least one outer side of the carrier body. The compensating foam layer is preferably arranged on at least one side of the carrier body that extends parallel to a main extension plane of the carrier body. The compensating foam layer is preferably arranged in particular on a largest side of the carrier body. The carrier body has in particular a cuboid shape. The compensating foam layer preferably has a cuboid shape, wherein a thickness of the compensating foam layer is significantly less than a thickness of the carrier body. The thickness of the compensating foam layer is preferably a maximum of 60%, preferably a maximum of 40%, and particularly preferably a maximum of 20% of a thickness of the carrier body.Preferably, the size of a largest side surface of the compensating foam layer corresponds at least approximately to the size of a largest side surface of the carrier body. The compensating foam layer consists in particular of an at least substantially homogeneous foam. The compensating foam layer preferably consists of a conventional foam, in particular a PU foam. The compensating foam layer can preferably consist of any form of polymer foam, preferably polyurethane foam of the polyether or polyester type. However, it would also be conceivable for the compensating foam layer to also consist of a composite foam. Preferably, the compensating foam layer has an advantageously homogeneous surface. The carrier body has in particular a strong structure.If the structure of the composite foam of the carrier body were to be transferred to the sanding element, it would result in a lower-quality product, as the recessed areas of the sanding element would not contribute to the sanding, and the sanding device would appear patchy. It can also compromise the quality of the surface finish of the workpiece. Using a higher density of composite foam can reduce surface irregularities because the particles are compressed more tightly, resulting in smaller particles that produce an overall smoother surface. However, as a general rule, the higher the density of the foam, the more uniform the surface. However, higher-density rebonded foams consume more material, which contradicts the concept of sustainability. Furthermore, the materials become harder as density increases.If the density is too high, the foam's flexibility drops below a level that allows the product to conform to the shape of the workpiece during sanding. The leveling foam layer is therefore preferably made of conventional foam. The leveling foam layer is different from a composite foam. The leveling foam layer is intended to compensate for unevenness in the substrate and provide a beneficially homogeneous surface.

[0014] Furthermore, it is proposed that the at least one compensating foam layer is arranged at least partially between the carrier body and the grinding element. The compensating foam layer is intended to compensate for unevenness of the carrier body and to provide an advantageously homogeneous surface for the grinding element. One solution for producing a grinding device with a surface that is well suited for grinding therefore consists in particular in designing the carrier unit as a sandwich and / or composite material. The compensating foam layer is in particular firmly connected to the carrier body, wherein the grinding element is in particular formed at least for a large part on a surface of the compensating foam layer. The compensating foam layer is preferably arranged between the carrier body and the grinding element in a direction perpendicular to a main extension plane of the grinding device.The leveling foam layer preferably contacts both the carrier body and the grinding element. This enables, in particular, an advantageously homogeneous surface of the grinding element and thus a favorable grinding result.

[0015] It is further proposed that the at least one compensating foam layer be bonded to the carrier body in a materially bonded manner, in particular by lamination. The carrier unit in particular has a sandwich structure. Preferably, the compensating foam layer is bonded to the carrier body by means of a conventional lamination process, such as flame lamination, flame lamination, and adhesive lamination. The compensating foam layer in particular has a thickness of 0.5 mm to 8 mm, preferably 1 mm to 5 mm, and particularly preferably 2 mm to 4 mm. The laminated carrier unit can in particular be processed into strips that can be coated with a suitable adhesive for the sanding unit. The coated strips can subsequently be converted into sanding blocks. This makes it possible, in particular, to produce an advantageously coherent carrier unit.Furthermore, it is particularly advantageous to apply an abrasive element to the carrier unit. This method is not limited to composite foams. The same methodology can also be applied with two different foam types, for example, to achieve different hardness profiles, different conformal behavior of the abrasive article, or to enable the use of lower-quality / lower-cost materials as fillers in foam abrasive articles.

[0016] It is further proposed that the carrier unit have at least two compensating foam layers, each arranged on opposite outer sides of the carrier body. The compensating foam layers are in particular arranged on opposite sanding sides, each aligned parallel to a main extension plane of the sanding device. The two compensating foam layers are provided in particular when the sanding device is designed as a sanding block, but other sanding articles with a foam backing are also conceivable. If only one main surface is used for sanding, only one side needs to be coated with a smoothing outer surface. The sides of the sanding device are supported by the carrier body; the loss of sanding efficiency at one edge is less important because it is used less. The edges, which are very important for a sanding process, are made from the higher quality foam.This gives them the expected high-quality surface intended for appropriate grinding devices.

[0017] Alternatively, it is proposed that the carrier unit consist entirely of the carrier body, with the abrasive element comprising at least one support layer, in particular a primer, made of a TPU adhesive, which is applied directly to the carrier body. Since the composite foam of the carrier body consists of particles, its surface is never completely flat or level. If the surface of the composite foam is transferred to the abrasive, this results in an inferior abrasive device, as the recessed areas of the abrasive device do not contribute to the grinding process and the article appears patchy. This occurs, for example, when conventional adhesives, such as solvent-based nitrile adhesives, are used.In particular, by using a high-melting TPU adhesive and coating the carrier body in a die-coating process, a film is created that minimally penetrates the structure of the carrier body, creating a film that creates a smoother and better-looking, flatter surface for the grinding unit on the carrier body. A TPU adhesive, especially one with a high melting point, is advantageous for creating a more uniform surface. Compared to conventional adhesives, TPU adhesive has unique properties that offer additional advantages and contribute to surface smoothness. The TPU adhesive is applied at a high temperature, in particular > 140 °C. This means in particular that the temperature of the TPU adhesive is much higher than that of the carrier body.As a result, the part of the TPU layer in contact with the substrate cools much faster than the part in contact with the air. The part that cools faster also solidifies, or experiences a rapid increase in viscosity. This part of the material then flows less. The other part of the TPU layer, on the other hand, cools less quickly. As a result, this material remains in a flowing state longer. The result is a layer that compensates for the unevenness of the substrate. The result is a layer in which the lower part does not penetrate as deeply into the material, while the upper part flows for longer to create a uniform surface and compensate for any unevenness. This effect can be further enhanced by applying an external heat source, such as an IR emitter, which creates an additional temperature gradient.This exposes the outer part to greater heat, allowing the outer part of the TPU adhesive to flow slightly more and smooth out further. This allows for a beneficially homogeneous grinding device to be provided, particularly with minimal manufacturing effort.

[0018] Furthermore, the invention is based on a method for producing the grinding device. In particular, it is proposed that, in at least one bonding step, at least one compensating foam layer of the carrier unit of the grinding device be laminated to at least one outer side of the carrier body of the carrier unit. Preferably, the compensating foam layer is bonded to the carrier body using a conventional lamination process, such as flame lamination, flame lamination, and adhesive lamination.

[0019] Furthermore, it is proposed that a support layer made of the TPU adhesive be applied to the carrier unit in at least one coating step. The TPU adhesive serves, in particular, as a carrier for abrasive grains. The abrasive grains are introduced, in particular sprinkled, into the TPU adhesive in a step following the coating step. However, it would also be conceivable for the abrasive grains to already be present in the TPU adhesive during a coating process. In particular, grain materials of natural and / or synthetic origin are conceivable for the plurality of abrasive grains.

[0020] It is further proposed that the support layer be actively heated in at least one smoothing step following the coating step. The TPU adhesive is applied at a high temperature, in particular > 140 °C. This means, in particular, that the temperature of the TPU adhesive is much higher than that of the carrier body. As a result, the part of the TPU layer in contact with the carrier body cools much faster than the part in contact with the air. The part that cools faster also solidifies or experiences a rapid increase in viscosity. This part of the material then flows less. The other part of the TPU layer, on the other hand, cools less quickly. As a result, this material remains in a flowing state longer. The result is a layer that compensates for the unevenness of the carrier body.This creates a layer where the lower part doesn't penetrate as deeply into the material, while the upper part flows longer to create a uniform surface and smooth out any unevenness. This effect can be further enhanced by applying an external heat source, such as an IR emitter, which creates an additional temperature gradient. This exposes the outer part to greater heat, allowing the outer part of the TPU adhesive to flow a little more and smooth out further.

[0021] The grinding device according to the invention and the method are not intended to be limited to the application and embodiment described above. In particular, the grinding device according to the invention and the method can have a number of individual elements, components, units, and method steps that differs from the number stated herein to fulfill a function described herein. Furthermore, in the value ranges specified in this disclosure, values ​​within the stated limits are also to be considered disclosed and can be used arbitrarily. drawing

[0022] Further advantages will become apparent from the following description of the drawings. The drawings illustrate two exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0023] They show: Fig. 1 shows a grinding device according to the invention with a carrier unit and with an abrasive grinding element in a schematic, perspective view, Fig. 2 shows the grinding device according to the invention with the carrier unit, which has a carrier body and two compensating foam layers, and with the abrasive grinding element in a schematic sectional view, Fig. 3 shows a schematic flow diagram of a method for producing the grinding device according to the invention, Fig. 4 shows an alternative grinding device according to the invention with a carrier unit and with an abrasive grinding element in a schematic, perspective view and Fig. 5 shows a schematic flow diagram of a method for producing the alternative grinding device according to the invention. Description of the embodiments

[0024] Figure 1shows a grinding device 10a. The grinding device 10a is formed by a manual grinding device 10a. The grinding device 10a is formed by a grinding block. However, other embodiments of the grinding device 10a that would be deemed appropriate by a person skilled in the art are also conceivable, such as sandpaper, a grinding pad, or abrasive fleece.

[0025] The grinding device 10a has a support unit 12a. The support unit 12a is cuboid-shaped. The support unit 12a is cut into a suitable cuboid shape, in particular from large plates. The support unit 12a forms a base body of the grinding device 10a. The support unit 12a serves to support an abrasive grinding element 16a. The support unit 12a has a support body 14a. The support body 14a is also cuboid-shaped. The support body 14a is formed by a support block. The support body 14a consists at least largely of an elastomeric foam. The support body 14a consists entirely of an elastomeric foam. The support body 14a consists at least partially of a composite foam. The support body 14a consists entirely of a composite foam. The composite foam is created, in particular, from the recyclable residues that arise during the processing of PUR foams.Foam flakes or leftover foam are collected and reprocessed with various additives that influence the properties of the composite foam. The materials to be processed are pressed and bonded.

[0026] Furthermore, the carrier unit 12a has at least one compensating foam layer 20a, 20a', which is arranged on at least one outer side of the carrier body 14a. The carrier unit 12a has two compensating foam layers 20a, 20a', each of which is arranged on opposite outer sides of the carrier body 14a. The compensating foam layers 20a, 20a' are arranged on opposite grinding sides, each of which is aligned parallel to a main extension plane 26a of the grinding device 10a. The compensating foam layers 20a, 20a' are arranged on the two largest sides of the carrier body 14a. The compensating foam layers 20a, 20a' each have a cuboid shape, wherein a thickness of the compensating foam layers 20a, 20a' is significantly less than a thickness of the carrier body 14a. A size of a largest side surface of the compensating foam layers 20a, 20a' corresponds in each case to a size of a largest side surface of the carrier body 14a.

[0027] The compensating foam layers 20a, 20a' each consist of an at least substantially homogeneous foam. The compensating foam layers 20a, 20a' each consist of a conventional foam, in particular a PU foam. The compensating foam layers 20a, 20a' can consist of any form of polymer foam, preferably polyurethane foam of the polyether or polyester type. However, it would also be conceivable for the compensating foam layers 20a, 20a' to also consist of a composite foam. The compensating foam layers 20a, 20a' advantageously have a homogeneous surface. The compensating foam layers 20a, 20a' are integrally bonded, in particular by lamination, to the carrier body 14a. The carrier unit 12a has a sandwich structure. The carrier unit 12a has three layers perpendicular to the main extension plane 26a, namely a first compensating foam layer 20a, the carrier body 14a and a second compensating foam layer 20a'.The compensating foam layers 20a, 20a' are bonded to the carrier body 14a using a conventional lamination process, such as flame lamination, flame bonding, and adhesive bonding. The compensating foam layers 20a, 20a' each have a thickness of 0.5 mm to 8 mm, preferably 1 mm to 5 mm, and particularly preferably 2 mm to 4 mm.

[0028] Furthermore, the grinding device 10a has an abrasive grinding element 16a arranged on at least one side of the carrier unit 12a. The grinding element 16a is formed by a grinding skin. The grinding element 16a is firmly connected to the carrier unit 12a. The grinding element 16a completely encompasses the carrier body 14a in at least one plane. The grinding element 16a is formed circumferentially in a plane perpendicular to a main extension direction 28a of the grinding device 10a. The grinding element 16a is arranged on four sides of the carrier unit 12a. The grinding element 16a covers four sides of the carrier unit 12a. The compensating foam layers 20a, 20a' are each arranged between the carrier body 14a and the grinding element 16a. The grinding element 16a is arranged partially directly on the compensating foam layers 20a, 20a' and partially directly on the carrier body 14a.The grinding element 16a is arranged directly on the leveling foam layers 20a, 20a' on the two largest surfaces 30a, 30a' of the grinding device 10a. Furthermore, the grinding element 16a is arranged directly on the support body 14a on two side surfaces 32a, 32a' of the grinding device 10a. At the four edges spanned by the grinding element 16a, the grinding element 16a is arranged on the leveling foam layers 20a, 20a'.

[0029] The grinding element 16a comprises a support layer 18a made of a TPU adhesive and abrasive grains located at least partially in the support layer 18a. The support layer 18a is formed from a base binder. The abrasive grains can, for example, consist at least largely of a mineral such as flint, quartz, sand, garnet, natural diamond, and / or corundum, silicon carbides, silicon oxide, aluminum oxide, chromium oxides, cubic boron nitride, and / or a composite material. The grinding element 16a is integrally bonded to the carrier unit 12a via the support layer 18a made of the TPU adhesive. The TPU adhesive is formed in particular by a hot-melt film and / or a hot-melt adhesive that is applied to the carrier body 14a by coating. The weight of the coating of the grinding element 16a is in particular in the range of 80-300 g / m 2< , preferably 140-180 g / m 2< .

[0030] Figure 3shows a schematic flow diagram of a method for manufacturing the grinding device 10a.

[0031] The method comprises a preparation step 34a, in which the carrier body 14a and the compensating foam layers 20a, 20a' are prepared. The carrier body 14a and the compensating foam layers 20a, 20a' are prepared in large sheets or plates, from which several carrier units 12a are later cut. This is followed by a joining step 22a. In the joining step 22a, the compensating foam layers 20a, 20a' of the carrier unit 12a of the grinding device 10a are each laminated to an outer side of the carrier body 14a of the carrier unit 12a. The compensating foam layers 20a, 20a' are preferably joined to the carrier body 14a using a conventional lamination process, such as flame lamination, flame lamination, and adhesive lamination. This is followed by a first separation step 36a in which the laminated plate is cut into several strips, which in turn form several carrier units 12a.This is followed by a coating step 24a. In the coating step 24a, a support layer 18a made of the TPU adhesive is applied to the carrier unit 12a or the strips. The support layer 18a is applied circumferentially to the carrier unit 12a or the strips. Subsequently, in a step 38a following the coating step 24a, the abrasive grains are introduced into the TPU adhesive, in particular sprinkled, and fixed. Cooling then takes place. This is followed by a second separation step 40a, in which the coated strips are separated, in particular cut, into individual grinding devices 10a.

[0032] In the Figures 4 and 5A further embodiment of the invention is shown. The following descriptions and the drawings are essentially limited to the differences between the embodiments, whereby with regard to components with the same designation, in particular with regard to components with the same reference numerals, reference is also made to the drawings and / or the description of the other embodiments, in particular to the Figures 1 to 3 To distinguish the embodiments, the letter a is added to the reference numerals of the embodiment in the Figures 1 to 3 In the examples of the Figures 4 and 5 the letter a is replaced by the letter b.

[0033] Figure 4 shows a grinding device 10b. The grinding device 10b is formed by a manual grinding device 10b. The grinding device 10b is formed by a grinding block.

[0034] The grinding device 10b has a support unit 12b. The support unit 12b is cuboid-shaped. The support unit 12b is cut into a suitable cuboid shape, in particular from large plates. The support unit 12b forms a base body of the grinding device 10b. The support unit 12b serves to support an abrasive grinding element 16b. The support unit 12b has a support body 14b. The support body 14b is also cuboid-shaped. The support body 14b is formed by a support block. The support body 14b consists at least largely of an elastomeric foam. The support body 14b consists entirely of an elastomeric foam. The support body 14b consists at least partially of a composite foam. The support body 14b consists entirely of a composite foam.

[0035] The carrier unit 12b consists entirely of the carrier body 14b.

[0036] Furthermore, the grinding device 10b has an abrasive grinding element 16b arranged on at least one side of the carrier unit 12b. The grinding element 16b is formed by a grinding skin. The grinding element 16a is firmly connected to the carrier unit 12b. The grinding element 16b completely encompasses the carrier body 14b in at least one plane. The grinding element 16b is designed to extend circumferentially in a plane perpendicular to a main extension direction 28b of the grinding device 10b. The grinding element 16b is arranged on four sides of the carrier unit 12b. The grinding element 16b covers four sides of the carrier unit 12b.

[0037] The abrasive element 16b comprises a support layer 18b made of a TPU adhesive and abrasive grains located at least partially in the support layer 18b. The support layer 18b is formed from a base binder. The support layer 18b is applied directly to the carrier body 14b. The abrasive element 16b is integrally bonded to the carrier unit 12b via the support layer 18b made of the TPU adhesive. The TPU adhesive is formed in particular by a hot-melt film and / or a hot-melt adhesive that is applied to the carrier body 14b by coating. The weight of the coating of the abrasive element 16b is in particular in the range of 80-300 g / m 2 , preferably 140-180 g / m 2 .In particular, by using a high-temperature melting TPU adhesive and coating the carrier body 14b in a die coating process, a film is created that minimally penetrates the structure of the carrier body 14b and creates a film that creates a more even and better-looking, flatter surface of the abrasive element 16b on the carrier body 14b.

[0038] Figure 5 shows a schematic flow diagram of a method for manufacturing the grinding device 10b.

[0039] The method comprises a provision step 34b in which the carrier body 14b is provided. The carrier body 14b is provided in particular in large sheets or plates, from which a plurality of carrier units 12b are later cut out. This is followed by a first separation step 36b in which the plate is cut into a plurality of strips, which in turn form a plurality of carrier units 12b. This is followed by a coating step 24b. In the coating step 24b, a support layer 18b made of the TPU adhesive is applied to the carrier unit 12b or the strips. The support layer 18b is applied circumferentially to the carrier unit 12b or the strips. The support layer 18b is applied in a die coating process using a high-melting TPU adhesive. The TPU adhesive is applied at a high temperature of in particular > 140°C.This means, in particular, that the temperature of the TPU adhesive is much higher than that of the carrier body 14b. As a result, the part of the TPU layer in contact with the carrier body 14b cools much faster than the part in contact with the air. The part that cools faster also solidifies, or rather, experiences a rapid increase in viscosity. This part of the material then flows less. The other part of the TPU layer, on the other hand, cools less quickly. As a result, this material remains in a flowing state longer. The result is a layer that compensates for the unevenness of the carrier body 14b. This creates a layer in which a lower part does not penetrate as deeply into the material and the upper part flows longer in order to create a uniform surface and compensate for unevenness. In a smoothing step 42b following the coating step 24b, the support layer 18b is then additionally actively heated.This can further enhance the smoothing effect. A heat source, such as an IR radiator, creates an additional temperature gradient. This exposes the outer part to greater heat, allowing the outer part of the TPU adhesive to flow a little more and smooth itself further. Subsequently, in a step 38b following the coating step 24b, the abrasive grains are introduced into the TPU adhesive, in particular sprinkled in, and fixed. Cooling then takes place. This is followed by a second separation step 40b, in which the coated strips are separated, in particular cut, into individual grinding devices 10b.

Claims

1. Grinding device, in particular manual grinding device, with a carrier unit (12a; 12b) which has a carrier body (14a; 14b), in particular a carrier block, which consists at least to a large extent of a, in particular elastomeric, foam, and with at least one abrasive grinding element (16a; 16b), in particular a grinding skin, arranged on at least one side of the carrier unit (12a; 12b), which is firmly connected to the carrier unit (12a; 12b), characterized in that the carrier body (14a; 14b) consists at least partially of a composite foam.

2. Grinding device according to claim 1, characterized in that the grinding element (16a; 16b) at least substantially completely encompasses the carrier body (14a; 14b) in at least one plane.

3. Grinding device according to claim 1 or 2, characterized in thatthe abrasive element (16a; 16b) comprises at least one support layer (18a; 18b), in particular a base binder, made of a TPU adhesive and abrasive grains located at least partially in the support layer (18a; 18b).

4. Grinding device according to claim 3, characterized in that the grinding element (16a; 16b) is materially connected to the carrier unit (12a; 12b) via the support layer (18a; 18b) made of the TPU adhesive.

5. Grinding device according to one of the preceding claims, characterized in that the carrier unit (12a) has at least one compensating foam layer (20a, 20a') which is arranged on at least one outer side of the carrier body (14a).

6. Grinding device according to claim 5, characterized in that the at least one compensating foam layer (20a, 20a') is arranged at least partially between the carrier body (14a) and the grinding element (16a).

7. Grinding device according to claim 5, characterized in thatthe at least one compensating foam layer (20a, 20a') is materially connected to the carrier body (14a), in particular by lamination.

8. Grinding device according to one of the preceding claims, characterized in that the carrier unit (12a) has at least two compensating foam layers (20a, 20a'), which are each arranged on opposite outer sides of the carrier body (14a).

9. Grinding device according to one of the preceding claims, characterized in that the carrier unit (12b) consists entirely of the carrier body (14b), wherein the grinding element (16b) has at least one support layer (18b), in particular a base binder, made of a TPU adhesive, which is applied directly to the carrier body (14b).

10. A method for producing a grinding device (10a; 10b) according to one of the preceding claims.

11. Method according to claim 10, characterized in thatin at least one connecting step (22a) at least one compensating foam layer (20a, 20a') of the carrier unit (12a) of the grinding device (10a) is laminated onto at least one outer side of the carrier body (14a) of the carrier unit (12a).

12. Method according to claim 10, characterized in that in at least one coating step (24a; 24b) a support layer (18a; 18b) made of the TPU adhesive is applied to the carrier unit (12a; 12b).

13. Method at least according to claim 10, characterized in that in at least one smoothing step (42b) following the coating step (24b), the base layer (18b) is actively heated.

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