TWI749040B - Rough grinding tools - Google Patents

Abstract

A rough grinding tool has a carrier and at least one grinding disc blank. The carrier contains abrasive grains for coarse grinding. The carrier is used to support the at least one grinding disc blank, and itself is also used for rough grinding. The rough grinding tool is simple, manufacturable and robust, and has high removal efficiency and long service life.

Description

Rough grinding tool

The present invention relates to a rough grinding tool as described in the preamble of claim 1, in particular for operating a hand grinder with a curved handle.

Rough machining means cutting materials with a large chip volume in the cutting process. In order to achieve a short processing time, the rough grinding tool should be able to achieve high removal efficiency and at the same time have a long service life.

EP 3 015 222 A1 discloses a grinding wheel with a carrier plate and a plurality of grinding disc blanks (Schleifronden). The carrier disc is graded in such a way that a plurality of ring segments are formed, and grinding disc blanks are respectively fixed on the ring segments. These grinding disc blanks form a multilayer grinding disc blank group in this way. The group of grinding disc blanks forms a step-like depression in a substantially truncated cone shape. As a result, the grinding disc blanks can be placed on the surface of the workpiece at different angles of attack, and almost complete processing of the grinding disc blank group is realized until the carrier plate reaches the surface of the workpiece and the grinding wheel is worn.

The present invention is based on the task of providing a simple, manufacturable and robust rough grinding tool with high removal efficiency and long service life.

This task is solved by a rough grinding tool having the characteristics described in claim 1. According to the present invention, the carrier is configured for coarse grinding and contains abrasive particles. The carrier is thus used to support at least one grinding disc blank during rough grinding on the one hand, and also for rough grinding itself on the other hand, thereby achieving high robustness and long service life of the rough grinding tool. The carrier is especially constructed such that it meets the safety requirement "single point side loading" of the German standard DIN EN 12413 "Safety requirements for abrasive bodies made of bonded abrasives" (version May 2011). The carrier is also simple in structure and simple to manufacture. By selecting abrasive grains, high removal efficiency is achieved for the workpiece to be processed. The rough grinding tool is constructed, for example, as a grinding wheel or as a grinding pot.

The rough grinding tool has one or more grinding disc blanks, and the grinding disc blanks are arranged on the carrier. In particular, the individual grinding disc blanks are designed to be ring-shaped. The grinding disc blank adjacent to the carrier is fixed on the carrier by bonding and/or riveting and/or screwing and/or bonding. If the rough grinding tool has a plurality of grinding disc blanks, each additional grinding disc blank is fixed to the underlying grinding disc blank by bonding and/or riveting and/or screwing and/or bonding. The bonding is carried out by means of an adhesive layer, which preferably contains a resin.

The rough grinding tool guarantees high removal efficiency. The grinding disc blanks of a grinding disc blank group are preferably arranged in a closely connected and unlaminated manner in the working area. Since the at least one grinding disc blank is not connected in the working area, it is removed from the grinding process in a simple manner after being worn. The at least one grinding disc blank is manufactured from an abrasive on a substrate. The abrasive particles are thus arranged on the carrier layer or substrate with the aid of the adhesive. After the abrasive particles are worn out, targeted wear of the carrier layer or the substrate is realized in the working area during the grinding process, so that the underlying grinding disc blank or carrier can contact the target in a simple and fast manner. The processed workpiece. This achieves high removal efficiency and high corrosiveness of the rough grinding tool. The working area of the at least one grinding disc blank is substantially annular and wheel-shaped.

The at least one grinding disc blank has at least one grinding layer, and the grinding layer has oriented abrasive grains and/or non-oriented abrasive grains. The abrasive particles are especially selected from diamond, cubic boron nitride (CBN), silicon carbide (SiC), natural corundum and/or synthetic corundum. The corundum is, for example, zirconium corundum and/or alumina (Al ₂ O ₃ ).

A rough grinding tool as described in claim 2 guarantees a long service life. The abrasive grains are bonded by means of an adhesive, and constitute an abrasive layer or abrasive area. The adhesive is especially a resin, such as a phenolic resin. Preferably, the abrasive layer has a thickness in the axial direction of the rough grinding tool, and the thickness is equal to the thickness of the carrier. This means that the carrier is constructed with an abrasive layer over its entire thickness. The abrasive particles are especially selected from diamond, cubic boron nitride (CBN), silicon carbide (SiC), natural corundum and/or synthetic corundum. The corundum is, for example, zirconium corundum and/or alumina (Al ₂ O ₃ ). The grinding layer or grinding area is formed at least on the upper side and/or the lower side of the carrier. The abrasive grains of the carrier are the same, and/or different from the abrasive grains of at least one abrasive disc blank. The polishing layer or polishing area of the carrier has the same or different abrasive grains.

A rough grinding tool as described in claim 3 guarantees a long service life. Preferably, the carrier has two carrier armors adjacent to the outside of the carrier, that is, adjacent to the upper and lower sides of the carrier. The at least one carrier armor is connected to the carrier by means of an adhesive or resin. The outer carrier armor is for example impregnated with no adhesive or resin. The outer carrier armor is preferably constructed as a fabric, in particular as a glass fabric or fiberglass fabric.

A rough grinding tool as described in claim 4 guarantees a long service life. Preferably the carrier has an internal carrier armor which is embedded in the abrasive layer or abrasive area. The inner carrier armor is penetrated by connected abrasive particles.

A rough grinding tool as described in claim 5 guarantees high robustness and long service life. Preferably, the outer diameter of the carrier is equal to the outer diameter of the grinding disc blank.

A rough grinding tool as described in claim 6 is simple, manufacturable and robust. A rough grinding tool constructed as a rough grinding wheel is also universal. The carrier and/or the at least one grinding disc blank and/or at least one of the grinding disc blank preferably has a curved portion.

A rough grinding tool as described in claim 7 has a particularly long service life. The at least one grinding disc blank, in particular a grinding disc blank group composed of a plurality of grinding disc blanks, is arranged between two carriers, and the carriers each contain abrasive grains for rough grinding. These carriers are constructed identically or differently. The first carrier is connected to the first grinding wafer blank of the grinding wafer blank group on the upper side, while the second carrier is connected to the last grinding wafer adjacent to the grinding wafer blank group on the lower side. The blanks are connected.

A rough grinding tool as described in claim 8 guarantees high robustness and long service life. The grinding disc blanks of the grinding disc blank group are sequentially stacked in layers.

A rough grinding tool as described in claim 9 ensures simple manufacturing. The grinding disc blanks are arranged one after the other in a simple manner, and the adjacent grinding disc blanks are connected to each other. This connection takes place especially by bonding. Preferably, adjacent grinding disc blanks are connected to each other in an internal connection area and not connected in a working area surrounding the connection area. The carrier and grinding disc blank set are thus simple and manufacturable.

A rough grinding tool as described in claim 10 ensures simple manufacturing. The first grinding disc blank is directly fixed on the carrier, on the contrary, the second grinding disc blank is only fixed on the first grinding disc blank. The second grinding disc blank is thus not directly, but only indirectly connected to the carrier. This connection takes place especially by bonding. Preferably, the grinding disc blank has an internal connection area in which the first grinding disc blank is connected to the carrier, and the second grinding disc blank is connected to the first grinding disc blank, And the grinding disc blank has a working area surrounding the connecting area, and the grinding disc blank is not connected in the working area.

A rough grinding tool as described in claim 11 ensures high removal efficiency. High corrosivity and high removal efficiency are achieved by oriented abrasive particles. This especially realizes the flat application of the rough grinding tool. The abrasive particles are preferably composed of diamond, cubic boron nitride (CBN), silicon carbide (SiC), natural corundum and/or synthetic corundum. The corundum is, for example, zirconium corundum and/or alumina (Al ₂ O ₃ ).

A rough grinding tool as described in claim 12 guarantees high robustness. The armor of the grinding disc blank realizes a high strength that prevents the corresponding grinding disc blank from breaking. The grinding disc blank armor is fixed on the at least one grinding disc blank in at least one working area. Preferably, the grinding disc blank armor is full-surface, that is, fixed to at least one grinding disc blank in both the working area and the connecting area. The grinding disc blank armor is in particular fixed on the back side of the at least one grinding disc blank. Preferably, the grinding disc blank armor is fixed on the back side of the grinding disc blank by means of an adhesive, such as phenolic resin. In particular, a grinding disc blank armor is fixed on each grinding disc blank. The grinding disc blank armor is connected to the back side or the underside of the grinding disc blank, for example, by a resin. Preferably, all grinding disc blanks are connected to the corresponding grinding disc blank armor. If required, only a single grinding disc blank can be connected to the grinding disc blank armor. Preferably, the armor of the grinding disc blank is fixed on the back side or the underside of the at least one grinding disc blank, and/or embedded in the grinding layer of the at least one grinding disc blank. The adhesive, especially resin, used to fix the armor of the grinding disc blank is especially used to fix the grinding disc blank on the carrier or on the grinding disc blank underneath.

A rough grinding tool as described in claim 13 ensures simple manufacturing. The at least one grinding disc blank is manufactured from an abrasive on a substrate. The substrate constitutes a carrier layer of abrasive grains disposed thereon. The carrier layer is constructed in particular as paper fibers, vulcanized fibers, non-woven fabrics and/or as carrier textiles, for example as fabrics and/or woven fabrics. The abrasive grains are arranged on the carrier layer directionally and/or non-directionally. The abrasive particles are connected to the carrier layer by means of an adhesive. In addition, a covering layer or covering adhesive can be provided on the abrasive grains.

A rough grinding tool as described in claim 14 ensures simple manufacturing and long service life. The carrier textile is especially a carrier fabric with at least one thread in the warp and weft directions. Preferably, the carrier textile is constructed as a polyester and cotton mixed fabric.

A rough grinding tool as described in claim 15 guarantees a long service life. The at least one grinding disc blank is hardened with a filling resin, so that the periodic deflection of the at least one grinding disc blank is reduced when the workpiece is processed. Due to the significant periodic deflection, the abrasive particles fall off the substrate before they wear out and have reached their material removal potential. In addition, the abrasive layer is weakened due to the shedding of abrasive particles, because adjacent abrasive particles can no longer support each other. The hardening prevents significant periodic deflection. This hardening is carried out by subsequently applying a filling resin to the grinding disc blank made of abrasive on the substrate and then curing the filling resin. The filling resin is selected from, for example, a collection of thermosetting plastics, elastomers, synthetic resins, and/or thermoplastic plastics, and combinations thereof. Preferably, the filling resin is a thermosetting plastic, such as a phenolic resin. After it is connected to the carrier or the underlying grinding disc blank, the grinding disc blank is placed or immersed in the filling resin in a simple manner. Preferably, the at least one grinding disc blank is impregnated with the filling resin in a tank.

A rough grinding tool as described in claim 16 ensures high robustness and long service life. Preferably, the at least one carrier armor and/or the corresponding abrasive disc blank armor is a fabric, in particular a fiberglass fabric.

A rough grinding tool as described in claim 17 guarantees a long service life. At least one abrasive layer of the corresponding abrasive disc blank contains an abrasive grain. Each grinding disc blank may have a grinding layer on the lower side facing the carrier and/or the upper side facing away from the carrier. Preferably, all grinding disc blanks have a grinding layer on the corresponding upper side and/or the corresponding lower side. The abrasive layers of the corresponding abrasive disc blanks are constructed of the same abrasive grains or different abrasive grains. In addition, the abrasive layers of different abrasive disc blanks are constructed by the same abrasive grains and/or by different abrasive grains.

The first embodiment will be explained below with reference to FIGS. 1 to 3. The rough grinding tool 1 is constructed as a rough grinding wheel, and has a wheel-shaped or disk-shaped carrier 2 and a grinding disc blank group 3. The carrier 2 and the grinding disc blank group 3 are concentrically formed with a through hole 5 with respect to the common axis M to fix the tool driving device. The carrier 2 constitutes an annular curved portion 6. A flat working area 7 is arranged on the radially outer side of the curved portion 6, on the contrary, a connecting area 8 and a clamping area 9 are arranged on the radially inner side of the curved portion 6. Alternatively, the rough grinding wheel can be constructed flat.

The grinding disc blank group 3 has a quantity of N grinding disc stocks S and an associated grinding disc stock armor A, wherein for the quantity N: 1≤N≤9, especially 2≤N≤8, and especially 3≤ N≤7. In FIG. 2 exemplarily shown is a grinding disc blank group 3 having four grinding disc blanks and four corresponding grinding armors, wherein the grinding disc blanks are specifically represented by S ₁ to S ₄ , and the respective grinding The armor of the wafer blank is represented _{by A 1} to A _4. The corresponding grinding disc blank armors A ₁ to A _{4 are} fixed on the back sides 10 of the corresponding respective grinding disc blanks S ₁ to S _4. This fixing is carried out, for example, over the entire surface by means of an adhesive, such as a phenolic resin. The corresponding grinding disc blank armors A ₁ to A _{4 are} arranged at least in the working area 7 of the corresponding grinding disc blanks S ₁ to S ₄ , and are fixed on the back side 10 over the entire surface. The corresponding grinding disc blank armors A ₁ to A _{4 are, for} example, a fabric made of glass fibers and/or a fabric made of jute fibers.

The first grinding disc blank S ₁ and the associated first grinding disc blank armor A ₁ are fixed on the carrier 2 in the connecting area 8. This fixing takes place especially by gluing. For example, a surrounding adhesive material layer 4 is applied in the connecting area 8 close to the bend 6, by means of which the first grinding wafer blank S ₁ and the associated grinding wafer blank armor A ₁ are bonded together . The adhesive material layer 4 in particular by adhesive or resin to construct, with which the abrasive which the round blank on the armored A ₁ is fixed to the wafer polishing blank S _1. The second grinding disc blank S ₂ includes a second grinding disc blank armor A ₂ which is fixed on the first grinding disc blank S ₁ in the connecting area 8. This fixing takes place especially by gluing. For example, in a corresponding manner, a surrounding adhesive material layer 4 is applied to the connecting area 8 close to the bend 6 by means of which the adhesive material layer is used for bonding. The bonding of the grinding wafer blank S ₂ and the underlying grinding wafer blank S ₁ is particularly carried out by using the adhesive or resin, wherein the adhesive or resin is also used to fix the grinding wafer blank armor A ₂ on The grinding disc blank S ₂ is on. The third grinding disc blank S ₃ together with the associated third grinding disc blank armor A ₃ are fixed on the second grinding disc blank S ₂ in a corresponding manner, and the fourth grinding disc blank S ₄ is connected with The corresponding fourth grinding disc blank armor A _{4 is} fixed on the third grinding disc blank S ₃ . The first grinding wafer blank S ₁ and the associated grinding wafer blank armor A _{1 are} thus fixed on the carrier 2, on the contrary, the other grinding wafer blanks S ₂ to S ₄ and the associated grinding wafer blank armor A are fixed on the carrier 2. ₂ to A _{4 are} fixed on the corresponding grinding disc blanks S ₁ to S ₃ below. The grinding disc blanks S ₂ to S ₄ together with the associated grinding disc blank armors A ₂ to A _{4 are} thus not directly fixed on the carrier 2. In this working area 7, the grinding wafer blanks S ₁ to S ₄ and the associated grinding wafer blank armors A ₁ to A ₄ are not fixed or connected, and are arranged closely in sequence without being laminated.

The carrier 2 has a carrier outer diameter D _T , and the grinding disc blanks S ₁ to S ₄ together with the corresponding grinding disc blank armors A ₁ to A ₄ have the grinding disc blank outer diameter D _S , which preferably has: 0.1 ·D _S ≤D _T ≤1.2·D _S , especially 0.5·D _S ≤D _T ≤1.1·D _S , and especially 0.8·D _S ≤D _T ≤D _S. In this embodiment according to FIG. 2, for example, D _T ≈D _S.

The grinding disc blanks S ₁ to S _{4 are} formed by abrasives on the substrate. The grinding disc blanks S ₁ to S ₄ comprise a carrier layer 11 to which oriented abrasive particles 13 are connected by means of an adhesive 12. A covering layer 14 is formed on the oriented abrasive particles 13. The carrier layer 11 constitutes the back side 10 to fix the corresponding grinding disc blank armors A ₁ to A ₄ . The adhesive 12 together with the abrasive particles 13 and the covering layer 14 constitute the corresponding abrasive layer 17 _{of the abrasive wafer blanks S 1} to S _4. The grinding layer 17 is arranged on _{the upper side of the respective grinding wafer blanks S 1} to S ₄ facing away from the carrier 2. Alternatively or in addition, the abrasive layer 17 may be arranged on the lower side facing the carrier 2. An abrasive layer 17 is preferably provided on the upper side and on the lower side, so that double-sided processing is achieved.

The carrier layer 11 is constructed, for example, as paper, vulcanized fiber, non-woven fabric and/or as a carrier textile. Preferably, the carrier textile includes polyester fiber, cotton fiber and/or glass fiber. The carrier layer 11 is constructed in particular as a polyester-cotton hybrid fabric. The adhesive 12 is, for example, a synthetic resin, especially a phenol resin. The oriented abrasive particles 13 are, for example, diamond abrasive particles. The abrasive particles 13 are especially selected from diamond, cubic boron nitride (CBN), silicon carbide (SiC), natural corundum and/or synthetic corundum. The corundum is, for example, zirconium corundum and/or alumina (Al ₂ O ₃ ).

The carrier 2 is designed for rough grinding. It includes an abrasive grain 16 connected by means of an adhesive 15 and carrier armors 18 and 19. The abrasive particles 16 are selected from, for example, diamond, cubic boron nitride (CBN), silicon carbide (SiC), natural corundum and/or synthetic corundum. The corundum is, for example, zirconium corundum and/or alumina (Al ₂ O ₃ ). The armor 18 toward the first wafer polishing blank S ₁ side of the carrier 20 and the outer side facing away from the lower polishing _a wafer disposed adjacent blank S 21, opposite to the support sheath 19 embedded in the carrier 2 And the adhesive 15 and abrasive particles 16 pass through. The carrier 2 has a carrier thickness d _T in the direction of the axis M, wherein the carrier 2 forms a rough grinding layer or grinding layer 22 with this thickness. The carrier armor 18, 19 is preferably constructed as a fabric. The fabric especially contains glass fibers and/or jute fibers.

The second embodiment of the present invention will be explained below with reference to FIG. 4. Different from the first embodiment, the rough grinding tool 1 as a rough grinding wheel structure has a second carrier 23 such that the grinding disc blank group 3 is arranged between the first carrier 2 and the second carrier 23. The second carrier 23 has the same structure as the first carrier 2. The second carrier 23 in the same manner as the first carrier 2 is oriented and fixed on the final polished wafer blank S ₄ in the connection area 8. This fixing takes place especially by gluing. In addition, the grinding disc blanks S ₁ to S _{4 are} not impregnated with a filling resin 24 that hardens the grinding disc blanks S ₁ to S _{4 after being} hardened. The filling resin 24 is thus additionally introduced into the grinding disc blanks S ₁ to S _{4 made} of the abrasive on the substrate. For this purpose, the rough grinding tool 1 _{is immersed in the filling resin 24 after fixing the grinding disc blanks S 1} to S ₄ , preferably by being immersed in a groove filled with the resin 24. The filling resin 24 is, for example, a synthetic resin, preferably a phenol resin. In particular, the filling resin 24 soaks the carrier layer 11 and hardens the fibers contained therein. For other configurations, refer to the description of the first embodiment.

A third embodiment is depicted in FIG. 5, which can also be combined with the first two embodiments. The grinding disc blanks S ₁ to S ₄ form corresponding two grinding layers 17 here, so that the corresponding grinding disc blank armors A ₁ to A _{4 are} embedded in the associated grinding disc blanks S ₁ to S ₄ . One of the abrasive layers 17 faces the carrier 2 or 23, on the contrary, the other abrasive layer 17 faces away from the carrier 2 or 23. This means that the grinding layer 17 is constructed on the upper and lower sides of the _{respective grinding wafer blanks S 1} to S _4. This realizes double-sided machining of the rough grinding tool 1. For other configurations, refer to the first embodiment.

According to the present invention, the carrier 2 or the carrier 2, 23 is used to support the grinding disc blank group 3, and at the same time, it is also used for rough grinding. Since the grinding disc blanks S ₁ to S ₄ and the associated grinding disc blank armors A ₁ to A ₄ are not connected in the working area 7 and are arranged closely in sequence without being laminated, a targeted Wear, so that the abrasive particles 13 that are not worn during the grinding process continue to be in contact with each other. Through the oriented abrasive particles 13, high removal efficiency and high corrosivity are achieved, so that the rough grinding tool 1 can be applied especially at a flat angle of attack and has the advantages of the present invention. The carrier 2 or the carrier 2, 23 itself has the characteristics of a rough grinding tool, in particular a rough grinding wheel. The rough grinding tool 1 is constructed, for example, as a rough grinding wheel or as a rough grinding pot. An additional paper separation layer can be provided between the grinding disc blank armor and the adjacent grinding disc blank if necessary.

1‧‧‧Rough grinding tool2, 23‧‧‧Carrier 3‧‧‧Grinding disc blank group ‧‧Connecting area 9‧‧‧Clamping area 10‧‧‧Back side 11‧‧‧Carrier layer 12‧‧‧Adhesive 13‧‧‧Abrasive particles 14‧‧‧Cover layer 15‧‧‧Adhesive 16‧‧ ‧Grit 17‧‧‧Grinding layer 18,19‧‧‧Carrier armor 20‧‧‧Upper side 21‧‧‧Lower side 22‧‧‧Grinding layer 24‧‧‧Filling resin A ₁ -A ₄ ‧‧‧Grinding Disc blank armor D _S ‧‧‧Grinding disc outer diameter D _T ‧‧‧Carrier outer diameter d _T ‧‧‧Carrier thickness M‧‧‧Axis S ₁ -S ₄ ‧‧‧Grinding disc blank

For other features, advantages, and details of the present invention, refer to the description of multiple embodiments below. in:

Fig. 1 shows a schematic cross-sectional view of a rough grinding tool according to a first embodiment,

Figure 2 shows an exploded view of the rough grinding tool of Figure 1 to show the configuration,

Fig. 3 shows an enlarged cross-sectional view of the carrier of the rough grinding tool of Fig. 1 and the first grinding disc blank and the armour of the first grinding disc blank,

Figure 4 shows a schematic cross-sectional view of a rough grinding tool according to a second embodiment, and

Fig. 5 shows an enlarged cross-sectional view of the carrier of the rough grinding tool in Figs. 1 and 4 and the first grinding disc blank and the corresponding first grinding disc blank armor.

1‧‧‧Rough grinding tools

2‧‧‧Carrier

3‧‧‧Grinding wafer blank group

5‧‧‧Through hole

6‧‧‧Bending part

7‧‧‧Working area

8‧‧‧Connecting area

9‧‧‧Clamping area

M‧‧‧Axis

S ₁ -S ₄ ‧‧‧Grinding wafer blank

Claims (17)

A rough grinding tool has a carrier, wherein the carrier contains abrasive grains for rough grinding and a through hole for fixing a tool driving device, characterized in that at least one grinding disc blank, wherein the at least one grinding circle The sheet blank configuration is formed with a connecting area and a working area surrounding the connecting area, and the at least one grinding disc blank is fixed in the connecting area and not fixed in the working area. The rough grinding tool according to claim 1, wherein the carrier is configured with a grinding area, and the grinding area contains abrasive grains connected by means of an adhesive. The rough grinding tool according to claim 1 or 2, wherein the carrier includes at least one carrier armor, and the carrier armor is particularly arranged adjacent to the upper side and/or the lower side of the carrier. The rough grinding tool according to claim 3, wherein at least one carrier armor is embedded in the grinding area. The rough grinding tool according to claim 1 or 2, wherein the carrier has an outer diameter D _T of the carrier, and the at least one grinding disc blank has an outer diameter D _{S of the} grinding disc blank, wherein: 0.1. D _S

D _T

1.2. D _S , especially 0.5. D _S

D _T

1.1. D _S , and especially 0.8. D _S

D _T

D _S. The rough grinding tool according to claim 1 or 2, wherein the carrier is configured to be wheel-shaped and especially has a curved portion. The rough grinding tool according to claim 1 or 2, wherein the at least one grinding disc blank is arranged on the first carrier and the second carrier Between the carriers. The rough grinding tool according to claim 1 or 2, wherein for the number N of the at least one grinding disc blank, the following applies: 1

N

9, especially 2

N

8, and especially 3

N

7. The rough grinding tool according to claim 1 or 2, wherein a plurality of grinding disc blanks are arranged overlappingly, wherein the first grinding disc blank is fixed on the carrier, and each other grinding disc blank is fixed below Grind the wafer blank. The rough grinding tool according to claim 1 or 2, wherein the first grinding disc blank is fixed on the carrier, and the second grinding disc blank is fixed on the first grinding disc blank. The rough grinding tool according to claim 1 or 2, wherein the at least one grinding disc blank has oriented abrasive grains. The rough grinding tool according to claim 1 or 2, wherein at least a partial area of the at least one grinding disc blank is fixed with a grinding disc blank armor. The rough grinding tool according to claim 1 or 2, wherein the at least one grinding disc blank comprises a carrier layer on which abrasive particles are arranged, wherein the carrier layer is especially used as paper, vulcanized fiber, non-woven fabric and / Or constructed as a carrier textile. The rough grinding tool according to claim 13, wherein the carrier textile comprises polyester fiber, cotton fiber and/or glass fiber, and especially a polyester-cotton mixture. The rough grinding tool according to claim 1 or 2, wherein: The at least one grinding disc blank is hardened with filling resin. The rough grinding tool according to claim 3, wherein the at least one carrier armor and/or grinding disc blank armor contains glass fiber and/or jute fiber. The rough grinding tool according to claim 1 or 2, wherein the at least one grinding disc blank is respectively configured with at least one grinding layer, and the at least one grinding layer is especially arranged on the upper side of the at least one grinding disc blank And/or underside.

Images