EP1561543A1 - Grinding belt - Google Patents

Abstract

The grinder belt, especially for polishing ceramics, has an underlay (1a,1b) of a polymer film or a woven fabric of mixed fibers with a null bond between their ends. The ends are chamfered away from each other, and the space is filled with fibers (2). The abrasive grinding material (4), e.g. diamonds or boron nitride, is attached to the underlay by a bonding agent (3) of a polymer with a reinforcement of carbon or glass fibers or wires.

Description

The present invention relates to an abrasive belt which especially suitable for grinding ceramic parts.

Ceramic parts are used for various applications used. For example, be on panels of Building facades or reminds of flow. Ceramic parts need usually polished to mirror gloss to such for Uses to be acceptable. This makes high demands on the accuracy of the abrasive belts to be used. conventional Sanding belts for other applications meet these high demands Requirements not. In particular, the documents as well their band connections in conventional abrasive belts too uneven.

This is particularly problematic because of bumps or over-thickness in the abrasive belt to irreparable Damage to the surface of the ceramic parts lead in usually make the ceramic workpiece void. One Post-processing is for sintered ceramics for dimensional reasons not feasible. Sintered ceramics often have a gradient at porosity on (above porous than below in the sintering direction), so that the part to the respective correct step not more identical.

It was the object of the present invention, an abrasive belt to provide, which for grinding ceramic parts suitable is.

This object is achieved by a grinding belt according to the independent Claims solved.

In particular, the present invention relates to an abrasive belt, comprising a polymer film or a mixed fiber fabric as Underlay, characterized in that the units of Pad are connected to each other via a zero connection.

According to the present invention is under a Null connection a connection of two tape units which are almost none, i. not more than 5 maximum μm has excessive thickness due to a protruding band.

It has been shown that a pad, which is a polymer film and their tape units via a zero connection connected to each other for grinding Ceramic parts required accuracy with very good traction exhibit. By using a polymer film, a Underlay will be provided, which does not require sanding has disadvantageously affecting unevenness. It has but also shown that as a base mixed fiber fabric can be used, if one of the documentary units over connects a null connection.

As a material for the polymer films according to the invention preferably polyester, polyethylene or polypropylene used. According to a preferred embodiment, the pad of the Sanding belt also made of a laminate of such Polymer film and a waterproof, finished Fabric backing exist.

According to the present invention, the pad of the Sanding belt preferably a thickness of 250 to 350 microns, in the Embodiment of a laminate of polymer film and fabric a Thickness of 300 to 600 microns.

On the pad the abrasive is applied. The Abrasive must be used for grinding ceramic parts have required hardness. According to the invention Abrasives in the usual grain sizes for grinding applications used. According to the present invention that is Abrasive preferably a superabrasive such as diamond (e.g. monocrystalline resin bond, monocrystalline metal bond, polycrystalline, coated) or cubic boron nitride (cBN).

The abrasive is made by means of a binder with the Pad connected. As binders can be common in this Area used materials are used. According to the invention, the binder is preferred to a phenolic resin in a proportion of 0-20 wt .-% phenoxy resin. However, it is also possible according to the present invention Binders, by inserting very strong fibers is reinforced. Preferably, small additions of chopped fibers during preparation the binder matrix incorporated in the same. Fibers of m and / or are preferred according to the invention for this purpose p-aramid (aromatic polyamide), ultra-high-strength polyethylene, highly oriented polyester, polyester, polyamide, carbon fibers or glass fibers and stranded wires. According to the invention especially preferred is the use of m-aramid fibers derived from the company Du Pont under the brand Nomex® and from the company Teijin sold under the trademark Teijinconex®, and / or p-aramid, which from the company Du Pont under the brand Kevlar®, from the company Twaron under the brand Twaron® and from the company Teijin under the brand Technora®, and / or by Ultra-high-strength polyethylene fibers produced by the company Toyobo be sold under the brand Dyneema®. Particularly preferred according to the invention is the use of Fibers of p-polyphenylene-2,6-benzobisoxazole, which are derived from the Toyobo under the brand Zylon®. However, combinations of all of the above can also be used according to the invention mentioned materials as fiber material for reinforcing the Binder matrix can be used.

The abrasive is applied to at least one surface of the Pad applied. Depending on the type of zero connection can Abrasive but also on both surfaces of the pad be applied. Especially if the pad is a laminate comprising a polymer film and a waterproof fabric, is the application of the abrasive on both surfaces of the thus formed pad preferred. In embodiments, at which the abrasive on both surfaces of the pad can be applied, for the different surfaces respectively Another abrasive or the same abrasive with different graininess (on the one surface coarse-grained abrasive, on the other surface fine-grained abrasive) can be used. In this way an abrasive belt is provided whose two surfaces have different grinding properties. According to the invention, this can be done in particular in the embodiment be realized in which a laminate of polymer film and waterproof fabric is used as a backing.

In the context of the present invention, the pad of the Abrasive belt, whether polymer film, mixed fiber fabric or laminate, also be provided with a backside coating. The Tape units of the pad together with the Back coating will be with a neutral connection connected. The backside coating is preferably made a synthetic resin and preferably has a thickness of 100 to 200 μm.

Particularly advantageous is the backside coating with Supplements provided. These can be organic or inorganic Be particles, e.g. Minerals, plastic granules or cork. As a result, for example, a damping during processing be achieved. With such an abrasive belt arise less Excessive scratches, as a grain or the entire sanding belt at Oversizes in the band can retreat.

The abrasive belt of the present invention is made by first providing the document and then the abrasive by means of a binder with the pad combines. The pad is made by connecting several Documentation units provided via a null connection. The Generation of these zero connections is described below with reference to FIG preferred embodiments explained in more detail.

According to the present invention, there are four different types of zero compounds is preferred. Preferred embodiments of Sanding belts according to the invention with these zero connections are shown in the non-limiting figures.

Show it:

Fig. 1

a grinding belt with a zero connection according to a first preferred embodiment,

Fig. 2

a grinding belt with a zero connection according to a second preferred embodiment,

Fig. 3

a grinding belt with a zero connection according to a third preferred embodiment,

Fig. 3A

another sanding belt with a zero connection according to a third preferred embodiment,

Fig. 4

a grinding belt with a zero connection according to a fourth preferred embodiment, and

Fig. 5

a grinding belt with a zero connection according to a fifth preferred embodiment.

A zero connection according to a first preferred Embodiment according to the present invention is characterized realized that two film units are shaped such that at least a portion of the surface of the film units, which adjacent to the other film unit, from the other Foil unit is beveled away and in the thus formed Space a fiber material is introduced.

As a fiber material, each may be conventionally fiber reinforced Foil used fiber material are used. According to the invention, it is preferably an aramid fiber (Keflar®).

The zero connection of the first preferred embodiment of present invention is produced by firstly at least a portion of the surface of the film units which adjacent to the other film unit, from the other Beveled foil unit away. This can be done on conventional, the Skilled art known manner, for example, by grinding the slides. According to the invention, each film unit is preferred in this case over a distance of 5-15 microns, preferably 5 to 10 microns beveled. The bevel can be over the entire width or only over a part of the width of each film unit available be. In this way, a wedge-shaped space between the produced two film units.

In this wedge-shaped space, a fiber material is introduced. According to the invention, this fibrous material preferably has a thickness from 50 to 100 μm. The length of the fiber material is so too choose that between the two foil units in the connected Condition on the side on which the film units on come next, a maximum gap of 1 mm available is. The fiber material is pressed into the wedge-shaped space, so that part of this space and this as possible the entire protruding space through the fiber material substantially is completely filled out. The fiber material is with the glued to both film units. Here the bonding is like that make sure that there is no excess thickness. For this can Any adhesive used for bonding Polymer parts with fiber parts is traditionally used. According to the invention, preference is given to a polyurethane-based adhesive.

The zero connection formed in this way can be loaded up to one Tensile force of about 200 N / cm.

A preferred example of this first embodiment of the The abrasive tape according to the invention is shown in FIG. Two Film units 1a and 1b were ground so that they over a distance a are bevelled. The bevel is in this Example not across the entire width of the film units educated. In the wedge-shaped cavity thus formed was a part made of fiber material 2 introduced. The fiber material 2 was pressed into the space between the film units 1a, 1b, so that the space between the straight sections of each other adjacent surfaces of the film units 1a, 1b as possible completely filled by the fiber material 2 and thus a the exactest possible connection between the film units 1a, 1b is guaranteed. The fiber material 2 was with the Foil units 1a and 1b glued, so that a solid Connection was formed. Here was the emergence of a Over-thickness avoided.

On the surface of the formed from the units 1a, 1b Underlay, which has as possible no gap, was then the abrasive 4 by means of a binder. 3 bound. In the present example it was the Abrasive 4 microns superabrasive and binder 3 microns Phenolic resin in a proportion of 0-20 wt .-% phenoxy resin.

A zero connection according to a second preferred Embodiment according to the present invention is characterized realized that the contiguous surfaces of the Film units beveled and glued to each other accurately are. This can be done in a conventional manner known to those skilled in the art done, for example, by grinding the slides. According to the invention, each film unit is preferably transferred over here a distance of 10-30 microns, preferably 10 to 20 microns bevelled. For gluing the film units, any adhesive used for bonding polymer parts conventionally used. Here the bonding is like that make sure that there is no excess thickness. According to the invention, preference is given to a polyurethane-based adhesive.

An example of this type of null connection is shown in FIG. 2 shown. The two film units 1a, 1b were so bevelled that the adjacent surfaces 5a, 5b these units fit together exactly. The surfaces 5a and 5b were glued together so that it was nowhere to an oversize comes.

On a surface of the formed from the units 1a, 1b Pad was then the abrasive 4 by means of a Binder 3 bound. In this example it was in the abrasive 4 to Superabrasiv and the Binder 3 to a phenolic resin in a proportion of 0-20 wt .-% Phenoxy. In the case of the present second embodiment it is also possible to use the abrasive on both surfaces of the Apply pad.

In an inventive abrasive belt according to a third preferred embodiment, the pad additionally comprises a layer of a waterproof fabric backing, which with the polymer film is connected. The pad is thus in In this case, a laminate of two layers. A zero connection according to a third preferred embodiment according to the present invention is realized in that each other offset butt joints of 2 foil units and two each Tissue units are present and glued. In other words are in the laminate, the layers of film and fabric to each other arranged offset, so that, for example, the ends of the Foil units not directly over the ends of the tissue units lie. In this way, the ends of the corresponding units by one unit of the other Materials bridged. This will create a stable zero connection realized in each case of the film units and the tissue units.

The connection of the laminate layers can be made by a person skilled in the art For this known methods can be achieved. According to the invention preferred is a hot melt laminating.

In the case of the present third embodiment, it is possible the abrasive on both surfaces of the pad apply, so both on the free surface of the Foil units as well as on the free surface of Tissue units. The abrasive is in each case by means of a Binders bound to the surfaces. The surfaces can in this case preferably different abrasives or a Have Schleifmitttel with different graininess, so that the sanding belt surfaces with different Has grinding properties.

In Fig. 3 and 3A is an example of an abrasive belt shown according to the third embodiment. The foil units 1a, 1b and the tissue units 6a, 6b became one another arranged offset and form a laminate underlay. The Units 1a, 1b and 6a, 6b were so hot-melt laminated connected to each other, that units 1a and 1b and 6a and 6b each form a zero connection with each other.

On one of the two surfaces of the laminate pad was then, depending on the grain size used, the Abrasive 4 bonded by means of a binder 3. For Coarse grain (P80-P600 or 180 microns - 25 microns) is preferably the Tissue side covered with grain, for finer grain (P800-P3000 or 20 μm - 3 μm) preferably the film side. In the present For example, the abrasive was 4 μm Superabrasive and the binder 3 with a phenolic resin with a proportion of 0-20 wt .-% phenoxy resin.

In an inventive abrasive belt according to a fourth preferred embodiment, the pad comprises a layer from a waterproof fabric underlay, which with a layer is made of mixed fiber fabric. The pad is thus in In this case, a laminate of two layers. The waterproof Fabric backing has an increased thickness of about 50-80 microns. This is required to make a null connection of the To realize mixed fiber fabric units. Otherwise would when scraping the fabric backing to an irreparable Damage to the mixed fiber fabric. A zero connection according to a fourth preferred embodiment according to the present invention is realized in that the Waterproof fabric pad at the position below the Joint of the mixed fiber fabric units 8a, 8b is scraped off. This can be done with conventional, the expert done with known methods. In this shabby area is a fiber reinforced compound foil, which is the Connecting film according to the first embodiment corresponds, inserted and glued. For gluing the foil units Any adhesive that is suitable for bonding can be used Polymer parts with fabric parts is used conventionally. According to the invention, preference is given to a polyurethane-based adhesive.

The connection of the laminate layers can be made by a person skilled in the art For this known methods can be achieved. According to the invention preferred is a hot melt laminating.

In Fig. 4 is an example of a grinding belt according to the third embodiment shown. The mixed fiber fabric units 8a, 8b and the thick tissue units 7a, 7b became one another arranged offset and form a laminate underlay. The Units 8a, 8b and 7a, 7b were laminated by hot-melt connected with each other. Subsequently, the tissue pad was below the junction of polymer film units 8a, 8b scraped. In the resulting space was the fiber-reinforced film 9 inserted and glued so that the Units 8a, 8b formed a zero connection.

On the surface formed by the mixed fiber fabric of the Laminate pad was then the abrasive 4 bound by means of a binder 3. In the present example The abrasive 4 was superabrasive and at the binder 3 to a phenolic resin in a proportion of 0-20 Wt .-% phenoxy resin.

In Fig. 5 is an abrasive belt according to another Embodiment shown. The polymer film units 1a, 1b were provided with a backside coating 10a, 10b. in the Area of connection of the film units 1a, 1b was the Back coating excluded. In the resulting Space was a fiber-reinforced film 9 is inserted, so in that the polymer film units 1a, 1b are connected via a zero compound were connected. The depth of the recess corresponds to the Thickness of the fiber-reinforced film 9.

The inventive abrasive belt is particularly suitable for Grinding of ceramic parts such as linings of Building facades or tiles. With the inventive Abrasive belt, ceramic parts can be polished to mirror finish, what with conventional abrasive belts due to their unevenness not possible.

Claims (17)

Abrasive belt, comprising a polymer film or a mixed fiber fabric as a base, characterized in that the base units (1a, 1b, 8a, 8b) are interconnected via a zero connection. Sanding belt according to claim 1, characterized in that a zero connection is realized in that in each case two film units (1a, 1b) of the base are shaped such that at least a portion of the surface of the film units (1a, 1b), which to the respective other film unit adjacent, is bevelled away from the other film unit and in the space formed thereby a fiber material (2) is introduced. Sanding belt according to claim 1, characterized in that a zero connection is realized in that the respectively adjacent surfaces (5a, 5b) of the film units (1a, 1b) are chamfered and glued to each other precisely fitting. Sanding belt according to claim 1, characterized in that the zero connection is realized in that mutually offset butt joints of in each case 2 film units (1a, 1b) and two waterproof fabric underlays (6a, 6b), which are connected to the film units (1a, 1b), present and glued. Sanding belt according to claim 1, characterized in that the base comprises a layer of mixed fiber fabric (8a, 8b) and in addition a thick layer of a waterproof fabric backing (6a, 6b, 7a, 7b), which with the layer of mixed fiber fabric (8a, 8b ) connected is. Sanding belt according to claim 5, characterized in that the zero connection is realized in that the fabric support (7a, 7b) below the compound of the film units (8a, 8b) removed and in this space a fiber-reinforced film (9) is introduced. An abrasive belt according to any one of claims 1 to 6, comprising Abrasive (4) on one or both surfaces of the Document. An abrasive belt according to claim 7, characterized in that one of the two surfaces of the abrasive belt is coated with the abrasive depending on the grain size. Sanding belt according to claim 7 or 8, characterized in that the abrasive (4) is selected from the group of Superabrasive such as diamond (eg monocrystalline resin-bond, monocrystalline metal-bond, polycrystalline, coated) or cubic boron nitride (cBN). Sanding belt according to one of claims 1 to 9, characterized in that the abrasive (4) with a binder (3) consisting of a phenolic resin and 0-20 wt .-% phenoxy resin, attached to the pad. Sanding belt according to one of claims 1 to 10, characterized in that the binder is fiber-reinforced. Abrasive belt according to claim 11, characterized in that the fiber material for reinforcing the binder is selected from the group consisting of m- and / or p-aramid, ultra high-strength polyethylene, highly oriented polyester, polyester, polyamide, p-polyphenylene-2,6-benzobisoxazole , Carbon fibers, glass fibers and stranded wires. Sanding belt according to one of claims 1 to 12, characterized in that the base has a thickness of 250 to 350 microns or in the case of a laminate of polymer film and fabric has a thickness of 300 to 600 microns. Sanding belt according to one of claims 1 to 13, characterized in that the polymer film (1a, 1b) consists of a material selected from the group consisting of polyester, polyethylene and polypropylene. Sanding belt according to one of claims 1 to 14, characterized in that the base units (1a, 1b; 8a, 8b) are provided with a backside coating (10a, 10b). Method for producing an abrasive belt according to one of claims 1 to 16, comprising the steps: a) providing a substrate comprising a polymer film (1a, 1b) or a mixed fiber fabric (8a, 8b), b) applying an abrasive (4) by means of a binder (3), wherein in step a) the pad is provided of a plurality of pad units by either at least a portion of the surface of the film units (1a, 1b), which adjoins a respective other film unit, bevelled away from the other film unit and into the space formed thereby Fiber material (2) is introduced, or by adjoining surfaces (5a, 5b) of film units (1a, 1b) are bevelled and glued to each other precisely fit, or by staggered joint joints of a laminate of 2 film units (1a, 1b) and two water-resistant In a laminate of mixed fiber fabric (8a, 8b) and waterproof fabric backing (7a, 7b), the fabric backing (7a, 7b) is removed below the junction of the blended fiber fabric units (8a, 8b) and a fiber-reinforced film (9) is introduced into this space. Use of an abrasive belt according to one of claims 1 up to 16 for grinding ceramic parts.

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