Method for producing an abrasive flap disk, and abrasive flap disk

Abstract

The invention relates to a method (100) for producing an abrasive flap disk (300), the abrasive flap disk (300) comprising abrasive flaps (204) and a carrier plate (200), the carrier plate (200) having an axis of rotation (230), and the method (100) comprising: - forming an integral bond (203) of the abrasive flaps (204) to the carrier plate (200) at a bond target point (205), in particular a circular bond target point, by means of an adhesive, - sealing the bond target point (205) toward the axis of rotation (230) before forming the integral bond (203), in order to prevent the adhesive from flowing from the bond target point (205) toward the axis of rotation (230) during the forming of the integral bond (203), the sealing being accomplished by means of a sealing element (210) which is separate from the carrier plate (200), and - removing the sealing element (210) from the integral bond (203) after the integral bond (203) has been formed.

Description

[0001] Method for manufacturing a flap grinding wheel and flap grinding wheel

[0002] Description

[0003] The invention relates to a method for manufacturing a flap grinding wheel. Furthermore, the invention relates to a flap grinding wheel.

[0004] The publication EP 1 142 673 A2 discloses a grinding wheel for a grinding tool, wherein the grinding wheel comprises a carrier plate and grinding elements attached to the carrier plate. The grinding flaps extend over part of the circumference around the axis of rotation and are arranged overlapping like roof tiles on the annular carrier section. The grinding flaps form an annular coating on the carrier section, with the individual grinding flaps being attached by means of an adhesive.

[0005] A disadvantage of conventional grinding wheels is that the abrasive elements can detach from the backing plate during operation of the grinding tool due to high centrifugal forces. This can render the grinding wheel partially unusable or cause injuries. Therefore, the secure attachment of the abrasive elements to the backing plate is of paramount importance for safety. Particularly when using a metallurgical bond between the abrasive elements and the backing plate, a considerable amount of adhesive is used to ensure a sufficiently strong connection. However, this results in excessive adhesive consumption and high costs.

[0006] The object of the present invention is to provide a method for manufacturing a flap disc which forms a particularly reliable, material-bonded connection between the abrasive elements and the backing plate and / or reduces the amount of adhesive required to form the material-bonded connection. A further object is to provide a flap disc.

[0007] The problem concerning the method is solved by a method with the features according to claim 1. Advantageous embodiments are described in the dependent claims.

[0008] According to the invention, a method for manufacturing a flap grinding wheel is provided, wherein the flap grinding wheel comprises grinding flaps and a carrier plate, wherein the carrier plate has an axis of rotation, and wherein the method comprises:

[0009] - Forming a material-bonded connection between the abrasive flaps and the backing plate at a connection point, in particular circular or ring-shaped, by means of an adhesive,

[0010] - Sealing the joint surface in the direction of the axis of rotation before the formation of the bond, in order to prevent the adhesive from flowing from the joint surface in the direction of the axis of rotation during the formation of the bond, wherein the sealing is carried out by means of a sealing element designed separately from the carrier plate, and

[0011] - Removal of the sealing element from the material-bonded joint after the formation of the material-bonded joint.

[0012] Since the sealing element is removed from the material-bonded connection after the formation of the material-bonded connection, the sealing element is not a component of the carrier plate or the flap disc.

[0013] Without the sealing element according to the invention, prior to the formation of the bond, the adhesive could be distributed uncontrollably over the substrate during the bond formation process. In other words, the sealing element prevents the adhesive from spreading into an area of ​​the substrate where it cannot be used to form the bond.The sealing element ensures, in particular, that the adhesive of the bonded joint accumulates or is located only in the area or places on the backing plate where the bonded joint between the abrasive flaps and the backing plate is formed and / or is intended to be formed, and / or where it can contribute to the strength of the bonded joint. The sealing element advantageously serves as a barrier for the adhesive of the bonded joint.In this way, a particularly strong, secure, and reliable material-bonded connection, especially an adhesive bond, is formed between the abrasive flaps and the backing plate, since the sealing element ensures that the majority, nearly all, or all of the adhesive used is available or utilized for forming the material-bonded connection. Preferably, this also allows for a significant reduction in the amount of adhesive used, as the adhesive is used extremely efficiently to form the material-bonded connection, since no adhesive reaches areas where it cannot contribute to the strength of the bond.

[0014] In principle, it is preferred if the material-bonded connection is an adhesive bond. It is particularly preferred if the adhesive bond is formed by means of an adhesive or a binder. Such an adhesive or binder is preferably liquid or viscous during application and then hardens.

[0015] A preferred embodiment is characterized in that the sealing element extends during sealing at least as far in a positive direction as the material-bonded connection to be formed, wherein the positive direction corresponds to a direction from the back to the front along the axis of rotation. This preferably applies by 360° around the axis of rotation.

[0016] Preferably, the sealing element is in physical contact with the carrier plate during the sealing process. The sealing element is preferably pressed or pushed against the carrier plate to increase the sealing effect. The axis of rotation is preferably an axis around which the carrier plate and / or the flap disc, particularly after its manufacture, can be driven for operation.

[0017] The connection preferably involves attaching the abrasive flaps to the backing plate.

[0018] The connection point is preferably the location where the connection is to be formed. The connection point is preferably a fastening point. In other words, the fastening is to be formed at the fastening point.

[0019] The circular or ring-shaped connection point preferably extends 360° around the axis of rotation.

[0020] Another embodiment of the invention is preferably characterized in that the method also comprises the following:

[0021] Arrange the grinding lamellae along a circular path, thereby forming a ring-shaped grinding lamella arrangement,

[0022] Positioning the sealing element both between the circular path and a center point of the circular path and adjacent to the intended connection point, positioning the adhesive on or at the intended connection point.

[0023] Because the sealing element is positioned between the circular path and its center point, it preferably acts as a barrier to the adhesive during the formation of the bond. The axis of rotation preferably passes through the center point of the circular path.

[0024] The adhesive is preferably applied continuously, i.e., without interruption, along the desired joint area. Alternatively, it is preferred if the adhesive is applied along the desired joint area by means of individual doses. By adjoining the desired joint area, the sealing element preferably dimensions, limits, and / or at least partially defines or determines the shape of the material-bonded connection.

[0025] It is preferred if the arrangement of the adhesive includes applying the adhesive to the abrasive flaps and / or the backing plate. For example, the adhesive can be applied to the backing plate in one or more circular or ring-shaped tracks.

[0026] The circular path preferably extends 360° around the axis of rotation.

[0027] Another embodiment of the invention is preferably characterized in that the method also comprises the following:

[0028] Pressing the carrier plate and the grinding lamella arrangement together in such a way that the adhesive on the joint surface is in contact, in particular physical or mechanical contact, with the grinding lamella arrangement, the carrier plate and the sealing element at the same time.

[0029] It is possible that the formation of the bond at the joint during pressing involves curing of the adhesive. Alternatively, curing can be carried out after the bond has formed or after pressing. For example, curing can be achieved by applying external heat. However, curing without such external heat is also preferred.

[0030] The pressing action is preferably achieved by pressing the carrier plate and the abrasive flap assembly against each other. This can involve a movement of the carrier plate and the abrasive flap assembly relative to each other.

[0031] Alternatively, it is conceivable that the abrasive flap assembly is fixed in position during pressing and only the backing plate is moved against the abrasive flap assembly. Alternatively, it is conceivable that the backing plate is fixed in position and only the abrasive flap assembly is moved against the backing plate during pressing. It is generally preferred that the adhesive is positioned between the abrasive flap assembly and the backing plate during pressing and is thus compressed.

[0032] Another embodiment of the invention is preferably characterized in that the adhesive is applied to one or the front side of the carrier plate before pressing the parts together, and the pressing together takes place with the front side of the carrier plate against the abrasive flap arrangement. The joining point is preferably located on the front side.

[0033] Another embodiment of the invention is preferably characterized in that the abrasive flaps are arranged by placing them on a die that encloses the circular path, and in particular, the sealing element is arranged by placing it on the die. The die is preferably a forming device, specifically a forming device for the flap disc, which encompasses the circular path. The die preferably has a recess designed as a shoulder or recess for the abrasive flaps. Preferably, the abrasive flaps are arranged in and / or along the circular path. For arranging the sealing element on the die, it is preferred that the die has a recess into which the sealing element can be inserted in order to arrange and / or position the sealing element on the die.

[0034] One embodiment of the invention is preferably characterized in that the sealing element is reusable and / or used, in particular reused, for sealing during the production of further flap discs. This reusability and reuse result in cost savings in the production of the flap discs.

[0035] Another embodiment of the invention is preferably characterized in that the sealing element has a surface that is adapted to the adhesive in such a way as to prevent a material bond or adhesion of the sealing element by means of the adhesive, and / or wherein the sealing element comprises, consists of, or is coated with a material that is adapted to the adhesive in such a way as to prevent a material bond of the sealing element by means of the adhesive. A particularly smooth surface of the sealing element is especially preferred in order to prevent a material bond of the sealing element by means of the adhesive. Preferably, the material is silicone. Alternatively, it is a silicone coating or silicone encapsulation of the sealing element.

[0036] Another embodiment of the invention is preferably characterized in that the sealing element is designed as a gasket, in particular with a round, oval, O-shaped, U-shaped or V-shaped cross-section, preferably comprising or consisting of silicone. The various cross-sections allow for individual adaptation to the requirements arising for the manufacture of the flap disc.

[0037] The problem with regard to the flap disc is solved by providing a flap disc manufactured according to the inventive method. This results in a flap disc that features a particularly secure attachment of the flaps to the backing plate, despite the use of a small amount of adhesive. Furthermore, it is particularly preferred that the backing plate has a constant material thickness. The backing plate can be made of metal, comprise metal components, and / or be manufactured by deep drawing.

[0038] Another embodiment of the invention is preferably characterized in that the bonded connection has a shape and / or surface finish defined by the sealing element in the direction of the axis of rotation or facing the axis of rotation. This is achieved by having the sealing element adjacent to the intended connection point, and thus to the subsequent bonded connection, during its formation. In other words, the contour, shape, or surface finish is created by the contact, in particular physical or mechanical, between the sealing element and the adhesive of the bonded connection during the formation of the bonded connection.

[0039] Preferably, the material-bonded connection extends in the positive direction by at least 50%, 80%, or 100% of the height of the abrasive flaps extending from the backing plate. In other words, the material-bonded connection, measured from the backing plate, extends in the positive direction by at least 50%, 80%, or 100% of the height of the abrasive flaps.

[0040] Furthermore, it is preferred if the material-bonded connection between the backing plate and the abrasive flaps extends away from the axis of rotation, preferably over the entire radial extent of the backing plate or at least 50%, 80%, or 90% of an overlap area of ​​the abrasive flaps with the backing plate. The radial extent preferably runs transversely or perpendicular to the axis of rotation. Regardless of this, it is preferred if the abrasive flaps are sickle-shaped flaps or flaps with a rectangular cross-section. The cross-section refers to a top view of the respective abrasive flaps and / or to a plane in which the axis of rotation of the backing plate and / or the flap disc extends.

[0041] The crescent-shaped abrasive flaps can have a pointed end circumferentially around the axis of rotation, which is further away from the axis of rotation of the flap disc than the opposite end circumferentially. In particular, the abrasive flaps can be designed as shown in EP 1 142 673 A2. The rectangular abrasive flaps can also be, for example, trapezoidal. Regardless of their shape, the abrasive flaps are arranged overlapping like roof tiles on the backing plate and form a ring of abrasive flaps.

[0042] A further embodiment of the invention preferably relates to a power tool for grinding, in particular for grinding metal and / or wood, wherein the power tool comprises the flap disc and a drive, in particular an electric motor, by means of which the flap disc can be driven for grinding operation. It is preferred if the flap disc is separable or detachable from the power tool. In this way, worn flap discs can be replaced by new flap discs.

[0043] The invention will now be explained in detail using exemplary embodiments and with reference to the drawings. The drawings show:

[0044] Fig. 1 shows an embodiment of the method according to the invention,

[0045] Fig. 2a shows a schematic view of the invention,

[0046] Fig. 2b is a sectional view AA from Fig. 2a, and

[0047] Fig. 3 shows an embodiment of the flap disc according to the invention.

[0048] Figure 1 shows an embodiment of the method 100 according to the invention for manufacturing a flap disc. The illustrated embodiment of the method 100 comprises ten process steps 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, which follow each other directly.

[0049] The first process step 101 includes the initialization of process 100.

[0050] The subsequent second process step 102, however, includes the provision of grinding flaps, a carrier plate, a sealing element and a die.

[0051] The third process step 103 involves arranging the grinding lamellae along a circular path of the die.

[0052] The fourth process step 104 comprises arranging the sealing element in a recess of the die, which is located within the circular path. This positions the sealing element between the center point of the circular path and the grinding flaps.

[0053] The fifth process step 105 then takes place, which involves applying adhesive to a connection point located between the abrasive flaps and the sealing element. The adhesive can be applied to the ring of abrasive flaps and / or to the carrier plate, for example as one or more circular traces.

[0054] The sixth process step, 106, involves pressing the abrasive flaps together with the backing plate. The backing plate is pressed against the abrasive flaps, with the adhesive located between the backing plate and the flaps. Since the adhesive is liquid or viscous during this process, it spreads along the backing plate. However, the sealing element prevents the adhesive from flowing from the intended bonding point towards the axis of rotation of the backing plate by forming a barrier.

[0055] The seventh process step 107 comprises the curing of the material bond between the abrasive flaps and the backing plate. Here, the adhesive cures in such a way that the abrasive flaps are attached to the backing plate by means of the adhesive.

[0056] The eighth process step 108 involves removing the sealing element and the finished flap disc from the die. The sealing element is also separated from the flap disc and removed, making it reusable.

[0057] The ninth process step 109 initiates a repetition of the process, beginning with the second process step 102, which includes the provision of further grinding flaps, another backing plate, but the same sealing element and the same die. If such a repetition of the process is not desired, for example, if the production of such flap discs is to be discontinued, the ninth process step 9 initiates the tenth process step 110, which includes the termination of the process.

[0058] Figure 2a shows a schematic view of the invention. It depicts a carrier plate 200, schematically shown in a top view. The dashed lines indicate the locations where the abrasive flaps 204 and the sealing element 210 are to be arranged during the manufacturing process. Also shown in dashed lines is the connection point 205, where a material-bonded connection between the abrasive flaps 204 and the carrier plate 200 is formed during the process according to the invention. The sealing element 210 forms a barrier between the center point 231 of the circular path along which the abrasive flaps 204 extend and the connection point 205. A cross-sectional view AA is also shown.

[0059] Figure 2b shows the sectional view AA of the section path AA from Figure 2a. However, unlike the representation in Figure 2a, a more detailed view is shown. The axis of rotation 230 of the carrier plate 200 and the positive direction 232, which extends along the axis of rotation 230 from the rear 201 of the carrier plate 200 towards the front 202 of the carrier plate 200, are visible. On the front 202 of the carrier plate 200, the grinding flaps 204 are arranged in a circular path of the die 220. The die 220 includes an annular recess 221 that extends 360° around the axis of rotation 230 and serves to receive and position the sealing element 210.The sealing element 210, which is designed as a silicone ring, prevents the adhesive from flowing towards the axis of rotation 230 at the joint point 205 to form the material-bonded connection 203 when the carrier plate 200 is pressed against the grinding flaps 204 and the adhesive by means of a centering device 222 while the material-bonded connection 203 is formed.

[0060] Figure 3 shows a flap disc 300, which was manufactured according to the inventive method from Figure 1. As already shown in Figure 2b, the axis of rotation 230 and the positive direction 232 are depicted. However, the abrasive flaps are not sickle-shaped flaps as shown in Figure 2b, but rather flaps that have a rectangular shape in their top view and / or in a plane in which the axis of rotation 230 extends. It can be seen that the material-bonded connection 203 has a contour defined by the sealing element, which abutted the connection point 205 during the formation of the material-bonded connection 203. Furthermore, the material-bonded connection extends further in the positive direction 232 than the contour of the carrier plate. List of reference numerals

[0061] 100 procedures

[0062] 101 First procedural step

[0063] 102 second procedural step

[0064] 103 third procedural step

[0065] 104 fourth procedural step

[0066] 105 fifth procedural step

[0067] 106 sixth procedural step

[0068] 107 seventh process step

[0069] 108 eighth procedural step

[0070] 109 ninth procedural step

[0071] 110 tenth procedural step

[0072] 200 carrier plates

[0073] 201 Back

[0074] 202 Front

[0075] 203 Material-bonded connection

[0076] 204 grinding flaps

[0077] 205 Connection point

[0078] 210 Sealing element

[0079] 220 die

[0080] 221 Exclusion

[0081] 222 Centering

[0082] 230 Rotation axis

[0083] 231 Center point

[0084] 232 positive direction

[0085] 300 flap disc

Claims

Method for manufacturing a flap grinding wheel and flap grinding wheel Claims 1. Method (100) for manufacturing a flap grinding wheel (300), wherein the flap grinding wheel (300) comprises grinding flaps (204) and a carrier plate (200), wherein the carrier plate (200) has a rotation axis (230), wherein the method (100) comprises: Forming a material-bonded connection (203) of the grinding flaps (204) with the carrier plate (200) at a connection point (205), in particular a circular one, by means of an adhesive, Sealing the connection point (205) in the direction of the axis of rotation (230) before the formation of the material-bonded connection (203) in order to prevent the adhesive from flowing from the connection point (205) in the direction of the axis of rotation (230) during the formation of the material-bonded connection (203), wherein the sealing is carried out by means of a sealing element (210) formed separately from the carrier plate (200), and Removing the sealing element (210) after the formation of the material-bonded connection (203) from the material-bonded connection (203).

2. Method (100) according to claim 1, wherein the method (100) comprises: Arranging the grinding lamellae (204) along a circular path, thereby forming a circular grinding lamella arrangement, Arranging the sealing element (210) both between the circular path and a center point (231) of the circular path and adjacent to the Interconnection point (205), and Applying the adhesive to the intended joining point (205).

3. Method (100) according to any one of the preceding claims, further comprising: Pressing the carrier plate (200) and the abrasive flap assembly together in such a way that the adhesive on the joint surface (205) is in contact simultaneously with the abrasive flap assembly, the carrier plate (200) and the sealing element (100).

4. Method (100) according to one of the preceding claims, wherein the adhesive is applied to a front side (202) of the carrier plate (200) prior to pressing together and the pressing together is carried out with the front side (202) of the carrier plate (200) against the abrasive flap arrangement.

5. Method (100) according to one of the preceding claims, wherein the arrangement of the grinding lamellae (204) is carried out by arranging the grinding lamellae on a die (220) which comprises the circular path and wherein, in particular, the arrangement of the sealing element (210) is carried out by arranging the sealing element (210) on the die (220).

6. Method (100) according to one of the preceding claims, wherein the sealing element is reusable and / or used for sealing during the manufacture of further flap grinding discs (300).

7. Method (100) according to one of the preceding claims, wherein the sealing element (210) has a surface which is adapted to the adhesive in such a way that a material-bonded connection of the sealing element (210) by means of the adhesive is prevented and / or wherein the sealing element (210) comprises a material or consists of a material or is coated with a material which is adapted to the adhesive in such a way that a material-bonded connection (203) of the sealing element (210) by means of the adhesive is prevented.

8. Method (100) according to one of the preceding claims, wherein the sealing element (210) is designed as a sealing ring, in particular with a round, oval, o-shaped, u-shaped or v-shaped cross-section, preferably comprising or consisting of silicone.

9. Flap grinding wheel (300), manufactured according to a method (100) according to one of the preceding claims.

10. Flap disc (300) according to claim 10, wherein the materially bonded connection (203) in the direction of the axis of rotation (230) has a shape and / or surface quality defined by the sealing element (210).

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