Vulcanized fiber grinding tool

Abstract

The invention relates to a vulcanized fiber grinding tool (1) comprising two vulcanized fiber grinding disks (2, 3) which are adhered to each other over the entire surface by means of an adhesive layer (4) arranged between the vulcanized fiber grinding disks (2, 3) such that the vulcanized fiber grinding disk (2, 3) outer faces provided with the grinding means point away from each other and the use of a support plate is not necessary.

Claims

1. A vulcanised fibre grinding tool, comprising: two vulcanised fibre grinding discs each having an inner side and an outer side, the inner side of each of the vulcanised fibre grinding discs adhered to one another over an entire surface thereof by an adhesive layer arranged between the vulcanised fibre grinding discs, the outer side of each of the vulcanised fibre grinding discs, which face away from one another, include an abrasive, a driver element embedded in the adhesive layer in a central region of the vulcanised fibre grinding tool, and the driver element is configured to connect the vulcanised fibre grinding tool to a mechanical drive.

2. The vulcanised fibre grinding tool according to claim 1, wherein: the vulcanised fibre grinding tool has a longitudinal centre plane, the driver element has a mounting surface configured to mount the vulcanised fibre grinding tool on the mechanical drive, and wherein the driver element is of a depressed-centre design so that the mounting surface is arranged axially offset from the longitudinal centre plane of the vulcanised fibre grinding tool.

3. The vulcanised fibre grinding tool according to claim 1, wherein: the driver element comprises a single- or multi-pitch screw thread or internal thread.

4. The vulcanised fibre grinding tool according to claim 1, wherein: the vulcanised fibre grinding tool has a longitudinal centre plane, and the grinding tool has a plurality of through holes arranged transversely to the longitudinal centre plane of the vulcanised fibre grinding tool.

5. The vulcanised fibre grinding tool according to claim 4, wherein: the vulcanised fibre grinding tool has an axis of rotation, and the plurality of through holes are located on one or more hole circles arranged concentrically to the axis of rotation of the vulcanised fibre grinding tool.

6. The vulcanised fibre grinding tool according to claim 4, wherein: each through hole of the plurality of through holes is elongated and has a drop-shaped form.

7. The vulcanised fibre grinding tool according to claim 6, wherein: each elongated through hole of the plurality of elongated through holes has a length and a width, and the width of each of the elongated through holes decreases along the length from a first end portion of the elongated through hole to a second end portion of the elongated through hole.

8. The vulcanised fibre grinding tool according to claim 7, wherein: the vulcanised fibre grinding tool has an axis of rotation, and the first end portion of each elongated through hole of the plurality of elongated through holes has a larger radial distance from the axis of rotation of the vulcanised fibre grinding tool than the second end portion of each elongated through hole of the plurality of elongated through holes.

9. The vulcanised fibre grinding tool according to claim 8, wherein: the vulcanised fibre grinding tool has a plurality of radius lines which each extend radially from the axis of rotation of the vulcanised fibre grinding tool, and the first end portion and the second end portion of each elongated through hole of the plurality of elongated through holes are arranged at a different radius line of the plurality of radius lines of the vulcanised fibre grinding tool.

10. The vulcanised fibre grinding tool according to claim 9, wherein: an angle is formed by the different radius lines of each elongated through hole of the plurality of elongated through holes about the axis of rotation in the longitudinal centre plane of the vulcanised fibre grinding tool, and the angle is at least 30?.

11. The vulcanised fibre grinding tool according to claim 6, wherein: the vulcanised fibre grinding tool has an axis of rotation, each elongated through hole of the plurality of elongated through holes has a first end portion and a second end portion, and the first end portion of each elongated through hole of the plurality of elongated through holes has a larger radial distance from the axis of rotation of the vulcanised fibre grinding tool than the second end portion of each elongated through hole of the plurality of elongated through holes.

12. A vulcanised fibre grinding tool, comprising: two vulcanised fibre grinding discs each having an inner side and an outer side, the inner side of each of the vulcanised fibre grinding discs adhered to one another over an entire surface thereof by an adhesive layer arranged between the vulcanised fibre grinding discs, the outer side of each of the vulcanised fibre grinding discs, which face away from one another, include an abrasive, the vulcanised fibre grinding tool having a longitudinal centre plane, the grinding tool has a plurality of through holes arranged transversely to the longitudinal centre plane of the vulcanised fibre grinding tool, and each through hole of the plurality of through holes is elongated and has a drop-shaped form.

13. The vulcanised fibre grinding tool according to claim 12, wherein: a driver element is arranged in a central region of the vulcanised fibre grinding tool to connect the vulcanised fibre grinding tool to a mechanical drive, and wherein the driver element extends through a central hole in each of the vulcanised fibre grinding discs and the vulcanised fibre grinding discs are fastened to the driver element.

14. The vulcanised fibre grinding tool according to claim 13, wherein: the driver element comprises a single- or multi-pitch screw thread or internal thread.

15. The vulcanised fibre grinding tool according to claim 12, wherein: the vulcanised fibre grinding tool has an axis of rotation, and the plurality of through holes are located on one or more hole circles arranged concentrically to the axis of rotation of the vulcanised fibre grinding tool.

16. The vulcanised fibre grinding tool according to claim 12, wherein: each elongated through hole of the plurality of elongated through holes has a length and a width, and the width of each of the elongated through holes decreases along the length from a first end portion of the elongated through hole to a second end portion of the elongated through hole.

17. The vulcanised fibre grinding tool according to claim 16, wherein: the vulcanised fibre grinding tool has an axis of rotation, and the first end portion of each elongated through hole of the plurality of elongated through holes has a larger radial distance from the axis of rotation of the vulcanised fibre grinding tool than the second end portion of each elongated through hole of the plurality of elongated through holes.

18. The vulcanised fibre grinding tool according to claim 17, wherein: the vulcanised fibre grinding tool has a plurality of radius lines which each extend radially from the axis of rotation of the vulcanised fibre grinding tool, and the first end portion and the second end portion of each elongated through hole of the plurality of elongated through holes are arranged at a different radius line of the plurality of radius lines of the vulcanised fibre grinding tool.

19. The vulcanised fibre grinding tool according to claim 18, wherein: an angle is formed by the different radius lines of each elongated through hole of the plurality of elongated through holes about the axis of rotation in the longitudinal centre plane of the vulcanised fibre grinding tool, and the angle is at least 30?.

20. The vulcanised fibre grinding tool according to claim 12, wherein: the vulcanised fibre grinding tool has an axis of rotation, each elongated through hole of the plurality of elongated through holes has a first end portion and a second end portion, and the first end portion of each elongated through hole of the plurality of elongated through holes has a larger radial distance from the axis of rotation of the vulcanised fibre grinding tool than the second end portion of each elongated through hole of the plurality of elongated through holes.

Description

(1) The invention will be explained in more detail below with reference to exemplary embodiments and with the aid of the accompanying drawings, which show:

(2) FIG. 1 a first embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(3) FIG. 2 the inventive vulcanised fibre grinding tool of FIG. 1, in cross-section;

(4) FIG. 3 a second embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(5) FIG. 4 the inventive vulcanised fibre grinding tool of FIG. 3, in cross-section;

(6) FIG. 5 a third embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(7) FIG. 6 the inventive vulcanised fibre grinding tool of FIG. 5, in cross-section;

(8) FIG. 7 a fourth embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(9) FIG. 8 the inventive vulcanised fibre grinding tool of FIG. 7, in cross-section;

(10) FIG. 9 a fifth embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(11) FIG. 10 the inventive vulcanised fibre grinding tool of FIG. 9, in cross-section;

(12) FIG. 11 a sixth embodiment of an inventive vulcanised fibre grinding tool, in plan view;

(13) FIG. 12 the inventive vulcanised fibre grinding tool of FIG. 11, in cross-section;

(14) FIG. 13 a seventh embodiment of an inventive vulcanised fibre grinding tool in plan view;

(15) FIG. 14 the inventive vulcanised fibre grinding tool of FIG. 13 on an angle grinder;

(16) FIG. 15 a further embodiment of an inventive vulcanised fibre grinding tool as a segment-like part of a disc; and

(17) FIG. 16 a modification of the embodiment of an inventive vulcanised fibre grinding tool of FIG. 15.

(18) The inventive vulcanised fibre grinding disc illustrated in the drawings is provided and designed to be driven in rotatory or rotatory oscillating manner, for example for a conventional angle grinder. The inventive vulcanised fibre grinding tool illustrated in the figures (denoted as a whole by 1) comprises two vulcanised fibre grinding discs 2 and 3, which are provided with an abrasive at least on one of their outer sides and are adhered to one another over the entire surface by means of an adhesive layer 4 arranged between the vulcanised fibre grinding discs 2, 3, so that the outer sides of the vulcanised fibre grinding discs 2, 3, which are provided with the abrasive, face away from one another. The adhesive layer 4 can be formed for example by an epoxy resin based adhesive.

(19) The first embodiment (shown in plan view in FIG. 1 and in cross-section in FIG. 2) of a vulcanised fibre grinding tool 1 according to the invention can be fastened exceptionally simply to a machine tool spindle 6 by means of a central hole 5 in conventional manner, e.g. with a washer and nut. This therefore results in pure material waste when the tool 1 becomes worn, which means that disposal is kept simple and disposal costs are therefore kept low, particularly when used on an industrial scale. The hole 5 is advantageously designed as a hole with a nominal diameter of 22.23 mm. As a result of the symmetrical construction of the grinding tool 1, the longitudinal centre plane 7 of the grinding tool 1 is located in the adhesive layer 4.

(20) As is clearly shown in FIG. 4, that embodiment of a grinding tool 1 according to the invention which is illustrated in FIGS. 3 and 4 furthermore has, in a central region of the vulcanised fibre grinding tool 1, a driver element 8 embedded in the adhesive layer 4 for the purpose of connecting the vulcanised fibre grinding tool 1 to a mechanical drive, for example a machine tool spindle 6 of an angle grinder 9, as shown in FIG. 14. The driver element 8 shown is advantageously manufactured as a metal pressed part and has an M14 or ?-11 thread pitch 10 integrally formed therein, as is also clearly shown in FIGS. 13 and 14. The grinding tool can therefore be screwed directly onto the machine tool spindle 6 of the angle grinder 9, which shortens the tool change times considerably and therefore improves the overall cost-effectiveness when using a grinding tool 1 according to the invention.

(21) A mounting surface 11 for mounting the vulcanised fibre grinding tool 1 on the mechanical drive, for example on a shaft collar or on a machine tool spindle 6 or a spacer block, is furthermore constructed on the driver element 8. To this end, the driver element 8 is of a depressed-centre design so that the mounting surface 11 is arranged axially offset from the longitudinal centre plane 7 of the vulcanised fibre grinding tool 1, as shown particularly clearly in FIG. 4. With an appropriately adapted thread length of the machine tool spindle 6 or the use of suitable spacer blocks so that the machine tool spindle 6 does not project beyond the mounting surface 11 on the side of the vulcanised fibre grinding tool 1 which is opposite this mounting surface, the grinding tool 1 according to the invention can be positioned for grinding over its entire surface on the side of the vulcanised fibre grinding tool 1 which is opposite to the mounting surface 11.

(22) In the embodiment of an inventive vulcanised fibre grinding tool 1 shown in FIGS. 5 and 6, another driver element 12 is arranged in the central region of the vulcanised fibre grinding tool 1 for the purpose of connecting the vulcanised fibre grinding tool 1 to a mechanical drive 6. This commercially available driver element 12 is adhered and fixedly clamped to the vulcanised fibre discs. A hexagon bolt 15 is integrally formed on a hub body 13 for the purpose of positioning a conventional tool when it is fastened or released from a drive spindle 6. A single-pitch, preferably multi-pitch, screw thread or internal thread is constructed in the hub body 13 as part of a quick-change fastening of the grinding tool 1 on a drive spindle 6.

(23) FIGS. 7 to 12 show embodiments of a grinding tool 1 according to the invention, which correspond to those in FIGS. 1 to 6 and which additionally have through holes 16 arranged transversely to the longitudinal centre plane 7 of the vulcanised fibre grinding tool 1. The through holes 16 are located on one (FIGS. 7, 8, 11, 12) or more (FIGS. 9, 10) hole circles 21 arranged concentrically to an axis of rotation 17 of the vulcanised fibre grinding tool 1. The number of through holes 16 can be 2, 3, 4, 5, 6, 7, 8, 9 or more, the through holes 16 should be arranged in a uniform distribution to avoid an imbalance of the grinding tool 1.

(24) In the embodiments of a grinding tool 1 according to the invention which are shown in FIGS. 13 and 14, the through holes 16 have an elongated, drop-shaped, trailing form, with the length of the through holes 16 preferably being at least three times the greatest width of the through holes 16. The width of the elongated through holes 16 furthermore decreases from a first end portion 18 of a through hole 16 to a second end portion 19 of the through hole 16. The first end portion 18 has a larger radial spacing from the axis of rotation 17 of the vulcanised fibre grinding tool 1 than the second end portion 19. The through holes 16 of these embodiments have a shape such as that often used to illustrate a comet with a tail. As shown, the elongated through holes 16 can have an intrinsically curved construction. The operator has a larger view of the total machining surface than is the case with circular through holes. It has proven advantageous for the end portion 18 to be arranged closer to the outer edge of the vulcanised fibre grinding tool 1 and the narrower second end portion 19 to be arranged closer to the axis of rotation 17. The first end portion 18 and the second end portion 19 of a through hole 16 are arranged here on different radius lines 22, 23 about the axis of rotation 17 of the vulcanised fibre grinding tool 1. The angle ? formed by the radius lines 22, 23 of a through hole 16 about the axis of rotation 17 in the longitudinal centre plane 7 of the vulcanised fibre grinding tool 1 is at least 30?, preferably not greater than 60?, in the embodiment shown approximately 40? to 45?.

(25) FIGS. 15 and 16 show further embodiments of a vulcanised fibre grinding tool 1 according to the invention, which is constructed as a segment-like part 20 of a disc for use with so-called multi-tools, which have a rotatory oscillating drive for the tool 1 and are otherwise of a similar design to an angle grinder 9 and can be used for fine and precise surface machining. As a result of the rotatory oscillating movement of the machine tool spindle 6, a driver element 14 with a form-fitting holder for the machine tool spindle 6 is advantageous. A hexagonal hole, as shown in FIG. 15, or an octuple star, as shown in FIG. 16, enable the vulcanised fibre grinding tool 1 to be connected to the machine tool spindle 6 in various basic positions depending on the most expedient positioning of the machine tool in relation to the workpiece. Such a vulcanised fibre grinding tool 1 in the form of a segment can also have through holes 16 with the advantages described above. An embodiment of this type is shown in FIG. 16. It goes without saying that such a vulcanised fibre grinding tool 1 with holes 16 in FIG. 16 can also be equipped with a driver element 14, as shown in FIG. 15, and vice versa. The through holes 16 can also have the elongated form and the arrangement described with reference to FIG. 13.

LIST OF REFERENCE SYMBOLS

(26) 1 Vulcanised fibre grinding tool, as a whole 2 Vulcanised fibre grinding disc 3 Vulcanised fibre grinding disc 4 Adhesive layer 5 Central hole 6 Machine tool spindle 7 Longitudinal centre plane 8 Driver element 9 Angle grinder 10 Thread pitch 11 Mounting surface 12 Driver element 13 Hub body 14 Driver element 15 Hexagon bolt 16 Through hole 17 Axis of rotation 18 First end portion 19 Second end portion 20 Segment-like part 21 Hole circle 22 Radius line 23 Radius line ? Angle