Abstract
The present invention discloses an abrading wheel comprising a circular core having an outer periphery, a rim arranged orthogonally to said circular core on said outer periphery, said rim comprising an inner surface and an outer surface, and a grit material disposed on at least part of said outer surface. Further, a plurality of openings are arranged in the core for providing an airflow directed towards the inner surface, and wherein the outer surface of the rim is provided with a plurality of grooves, and where a main part of the grit material is disposed on said outer surface of said rim on spaces between said grooves. Thereby, the abrading wheel is cooled during operation, heat is more easily dissipated, and accumulation of particles from the product being grinded is minimised.
Claims
1. An abrading wheel comprising: a circular core having an outer periphery, a rim arranged orthogonally to said circular core on said outer periphery, said rim comprising an inner surface and an outer surface, and a grit material disposed on at least part of said outer surface, wherein a plurality of openings are arranged in said core for providing an airflow directed towards said inner surface, and wherein the outer surface of said rim is provided with a plurality of grooves twisting around a central axis of the abrading wheel and arranged in a helix or tilted relative to the outer periphery, and where a main part of said grit material is disposed on said outer surface of said rim on spaces between said grooves, whereby particles formed from a product being grinded are guided away from the abrading wheel along said grooves.
2. An abrading wheel according to claim 1, wherein the circular core comprises a central axis and a central aperture for mounting the abrading wheel on a rotation tool.
3. An abrading wheel according to claim 1, wherein the cross section of the grooves are V-shaped.
4. An abrading wheel according to claim 1, wherein the plurality of grooves are arranged in a helix having an axis collinear and coinciding with the central axis.
5. An abrading wheel according to claim 1, wherein the plurality of grooves are tilted relative to an edge of the rim.
6. An abrading wheel according to claim 1, wherein the plurality of grooves are arranged parallel to each other and parallel to the outer periphery of the circular core.
7. An abrading wheel according to claim 1, wherein the rim is a ribbon mounted onto the outer periphery of the circular core along an edge of said ribbon.
8. An abrading wheel according to claim 1, wherein a tongue is attached to each opening of the circular core, a plurality of tongues thereby being arranged in said circular core.
9. An abrading wheel according to claim 1, wherein the tongues are formed from excess material bent away from the openings, the tongues thereby being an integral part of the circular core.
10. An abrading wheel according to claim 1, wherein the tongues are oriented such that air is forced onto the inner surface of the rim, thereby providing air cooling to the abrading wheel.
11. An abrading wheel according to claim 1, wherein the grit material forms an overhang above said grooves.
12. An abrading wheel according to claim 1, wherein the grit material is tungsten carbide
13. An abrading wheel according to claim 1, wherein the grit size is between 14 and 220.
14. An abrading wheel according to claim 1 any of the preceding claims, wherein said abrading wheel is mounted onto a rotation tool, said rotation tool being capable of providing rotation around a central axis of the abrading wheel.
15. An apparatus, comprising: a wheel with a central axis, a top, a bottom, and an outer, peripheral surface, the wheel including grooves arranged transversely across the outer peripheral surface from the top to the bottom, the grooves have an angle relative to the central axis, the wheel also having openings disposed in a circular pattern and penetrating between the top and the bottom; and grit material disposed on the outer peripheral surface and covering space formed between the grooves and the top and the bottom of the wheel.
16. An apparatus according to claim 15, wherein the grooves are disposed in a helix pattern.
17. An apparatus according to claim 15, wherein the grit material overhangs into the grooves.
18. An apparatus according to claim 15, wherein the grit material overhangs into the grooves from both sides.
19. An apparatus according to claim 15, further comprising: covers disposed only partially over each of the openings in the wheel.
20. An apparatus according to claim 15, further comprising: covers disposed only partially over each of the openings in the wheel, the covers arranged at an angle relative to the top and the bottom of the wheel.
Description
SHORT LIST OF THE DRAWINGS
[0037] In the following, example embodiments are described according to the invention, where
[0038] FIG. 1 illustrates a perspective view of an abrading wheel according to the invention.
[0039] FIG. 2 illustrates a second perspective view of an abrading wheel according to the invention.
[0040] FIG. 3 illustrates a top view of an abrading wheel according to the invention.
[0041] FIG. 4 illustrates a plurality of cross-sectional views of an abrading wheel according to the invention.
[0042] FIG. 5 illustrates an example of an outer surface of an abrading wheel according to the invention.
[0043] FIG. 6 illustrates a second example of an outer surface of an abrading wheel according to the invention.
[0044] FIG. 7 illustrates a close up cross-sectional view of a groove in an outer surface on an abrading wheel according to the invention.
DETAILED DESCRIPTION OF DRAWINGS
[0045] In the following, the invention is described in detail through embodiments thereof that should not be thought of as limiting to the scope of the invention.
[0046] FIG. 1 is a perspective view of a part of an abrading wheel 100 according to the invention. The abrading wheel 100 comprises a circular core 101 having an outer periphery 103 and a central aperture 105. Said central aperture 105 is arranged in a depression 109. Said depression 109 protrudes into an inner volume (not shown) partly defined by said circular core 101 and a rim 111 arranged orthogonally to said core 101 on said outer periphery 103. Thus, the abrading wheel 100 may be said to be bowl-shaped with a central depression 109. Preferably, the depression 109 is an integral part of the core 101 therefore being considered as part of the core 101 in this context. Preferably, the central aperture 105 comprises at least one indentation 107 for mounting the abrading wheel 100 securely onto a rotation tool (not shown). The indentation 107 may be formed to correspond to a protrusion on said rotation tool (not shown). Said rotation tool may be used to rotate the abrading wheel 100 around a central axis L by engaging with the central aperture 105 and the at least one indentation 107. The rim 111 may be either mounted through e.g. welding onto the outer periphery 103 of the core 101, or the combined rim 111 and core 101 may be formed from a single piece of material, such that the outer periphery 103 is formed when bending/stamping said single piece of material. Alternatively, the core 101 and rim 111 are formed in a casting process. The core 101 is equipped with a plurality of openings 121. Preferably, said openings 121 are arranged equiangularly in a circular pattern at a fixed distance from a centre point of the central opening 105. The openings 121 are equipped with tongues 123, said tongues 123 preferably being an integral part of the core 101 and formed from bending the material along an uncut edge 124. For example, the openings 121 may be rectangular, such that the tongues 123 are formed from cutting along three edges thus leaving a fourth edge uncut and thereby allowing said fourth edge to be bent. Preferably, the tongues 123 are bent towards the inner volume (not shown). Preferably, the tongues 123 are bent evenly for all openings 121, such that a homogenous pattern of the openings 121 and tongues 123 is formed. When the abrading wheel 100 is set into rotation by a rotation tool, the tongues and accompanying openings draw in an air flow, such that said air is forced onto an inner surface (not shown) of the rim 111. Thereby, said air flow provides air cooling of the abrading wheel. Air cooling is essential when using the abrading wheel 100 for grinding purposes, where heating may occur due to friction.
[0047] The rim 111 is arranged orthogonally to the plane of the core 101, i.e. the rim extends in a direction parallel to the central axis L. The rim comprises an outer surface 113 and an inner surface (not shown). The inner surface is oriented towards the inner volume (not shown) of the abrading wheel 100 partly defined by the core 101 and the rim 111. The outer surface 113 comprises a plurality of grooves 131, for example carved into said outer surface. Said plurality of grooves 131 twists around the central axis L. Preferably, the grooves 131 are arranged in a helix with an axis collinear and coinciding with the central axis L. The helix and the grooves 131 sketched in FIG. 1 are highly exaggerated. Alternatively, the grooves 131 are parallel to each other and to the outer periphery 103 of the core 101. Alternatively, the grooves 131 are tilted relative to the outer periphery 103. Between said grooves 131, intermediate protruding spaces 132 are formed, said spaces 132 inevitably having the same course, e.g. a helix, as the grooves 131. A grit material 141 is disposed primarily onto said spaces 132 thereby leaving the grooves 131 free of grit material 141. See FIG. 5a and FIG. 6a for a cross-sectional view of the grooves 131, the spaces 132 and the disposed grit material 141. Said grit material 141 is made from a hard material such as tungsten carbide having a hardness of 9 on the Mohs-scale. When the abrading wheel 100 is set into rotation and a product is applied onto the grit, the grit material 141 grinds said product. Due to the absence of grit material 141 in the grooves 131, particles grinded off the applied product are less likely to accumulate in the grooves thereby increasing the lifetime of the abrading wheel 100. In other words, particles entering the grooves 131 are free to move and eventually escape said grooves 131, contrary to the case wherein grit material 141 would be disposed in the grooves 131, whereby particles would get trapped and accumulate more easily.
[0048] By arranging the grooves 131 and accompanying intermediate spaces 132 in a helix or tilted relative to the outer periphery 103, a larger amount of grit material 141 makes contact with the product to be grinded at any given time during rotation of the abrading wheel 100, assuming the product makes normal incident onto the rim 111. In other words, the helix arranged or tilted grooves 131 and spaces 132 provide an increased free space for a product making contact to the grit material 132 disposed in the spaces 132. Thus, by the grooves 131 and accompanying spaces 132 being tilted or arranged in a helix, the grinding efficiency of the abrading wheel 100 is increased.
[0049] A further effect of the grooves 131 and the accompanying intermediate spaces 132 being arranged in a helix or tilted relative to the outer periphery 103 is that the particles formed by grinding a product on the abrading wheel 100 are guided out of the abrading wheel. In other words, grooves 131 arranged in a helix or tilted inevitably comprise ends 133 terminating along an edge of the rim 111, where said ends 133 allow the particles to escape the abrading wheel 100.
[0050] The presence of grooves 131 further increases the surface area of the abrading wheel 100 which in turn increases the dissipation of heat and thereby increases the cooling capabilities of said abrading wheel 100.
[0051] FIG. 2 is a perspective view of the part of the abrading wheel 100 of FIG. 1 shown from another angle. In this view, the inner volume partly defined by the core 101 and the rim 111 is exposed. The inner surface 115 of the rim is shown in this view. The depression 109 protrudes into said inner volume. The central aperture 105 and the indentation 107 are partly visible. The tongues 123 are shown to be bent into the inner volume along an uncut edge 124. Further, the openings 121 are shown to be cut along three edges 221, 222, 223, thereby leaving the uncut edge 124 uncut. The tongues 123 are all bent along the same uncut edge 124 relative to the core 101 thereby forming a homogenous pattern along the entire diameter along which the openings 121 are arranged. Preferably, the uncut edge 124 is orthogonal to the rim 111. A grit material 141 is disposed on spaces between a plurality of grooves (not shown in this embodiment) on the outer surface 113 of the rim 111. The grit material 141 is shown in further detail in FIG. 5 and FIG. 6.
[0052] FIG. 3 shows a top view of the abrading wheel 100. The top view exposes the inner volume. The direction of the central axis L serves as reference to FIG. 1. The plurality of openings 121 is shown without tongues 123. However, it should be noted that in the case of said tongues 123 being an integral part of the core 101, it is not optional to detach or attach said tongues 123. The plurality of openings 121 is shown to be equiangularly spaced on the core 101 around the central axis L. The central aperture 105 is shown to be arranged symmetrically around the central axis L. The abrading wheel 100 is shown with two indentations 107, 107′, for improved stability when mounting the abrading wheel onto a rotation tool (not shown). The depression 109 is indicated by a dotted line. The grit material 141 is shown disposed on an outer surface 113 of the rim 111. Three cross sections, A-A, B-B, and C-C, are indicated in FIG. 4 and described in further detail below.
[0053] FIG. 4 shows the cross sections indicated in FIG. 3.
[0054] FIG. 4a illustrates the cross section A-A comprising two of the plurality of openings 121. The tongues 123 are shown to be an integral part of the core 101 and being bent along an uncut edge 124 indicated by a dotted line.
[0055] FIG. 4b illustrates the cross section B-B. The tongue 123 attached to the opening 121 is shown as a displaced dotted box due to the choice of viewing angle. The rim 111 is shown being arranged orthogonally to the core 101. An edge of the rim 101 is shown to be mounted onto the outer periphery 103 of the core 101, the rim 111 thereby forming an acute angle of 90 degrees and an obtuse angle of 270 degrees relative to the core 101. The rim 111 comprises a plurality of grooves 131 arranged in the outer surface 113. The plurality of grooves 131 are separated by a plurality of spaces 132. A grit material 141 is disposed onto said spaces 132.
[0056] FIG. 4c illustrates the cross section C-C. The abrading wheel is rotationally symmetric around the central axis L. The direction of the central axis L corresponds to the direction given from FIG. 1. The depression 109 protrudes towards the inner volume partly formed by the core 101 and the rim 111. More specifically, the depression 109 displaces the central aperture 105 towards a midway point defined from the width of the rim 111. Thereby, stability of the abrading wheel 100 is increased when said abrading wheel 101 is exposed to rotational forces.
[0057] FIG. 5 and FIG. 6 show two possible excerpts of the outer surface 113. For reference, the orientation of the excerpts relative to the rim 111 is indicated by the directions x and z which are further defined in FIG. 1. A cross view of each excerpt is shown in FIG. 5a and FIG. 6a. The excerpts are examples of possible arrangements of the grooves 131 and accompanying spaces 132 thereby not limiting the scope of the invention.
[0058] FIG. 5 illustrates an excerpt of an outer surface 113 comprising a large separation of grooves 131, i.e. large spaces 132. Further, the grooves 131 and the accompanying spaces 132 are tilted at an angle 1 relative to the x-direction. The tilt forms a helix along the circumference of the rim 111 and around an axis coinciding with the central axis L (not shown). The grit material 141 is disposed on the spaces 132, such that the grooves 131 are free of grit material 141. A shaded triangle indicates a possible impact area 150 for a product to be grinded by the abrading wheel 100. During rotation, a product making normal incident, i.e. “entering” the grit from the short cathetus 150a, as shown by the direction of the arrow E, makes impact with the grit material 141 along the entire length of the hypotenuse 150c. In the case of non-tilted grooves 131 and spaces 132, the impact would be reduced to the width of the spaces 132 onto which the grit material 141 is disposed. Thereby, said impact area 150 illustrates the increased efficiency of the abrading wheel 100, when the grooves 131 and accompanying spaces 132 are arranged in a helix or tilted.
[0059] FIG. 5a illustrates a cross-sectional view of the excerpt in FIG. 5. Preferably, the grooves 131 are V-shaped as illustrated. Preferably, the grit material 141 overhangs parts of the grooves 131 illustrated by the overhang 142.
[0060] FIG. 6 and FIG. 6a (cross-sectional view) illustrate an excerpt of an outer surface 113 comprising a small separation of grooves 131, i.e. narrow spaces 132. Further, the tilt given by the angle 1 is smaller than the excerpt illustrated in FIG. 5.
[0061] FIG. 7 illustrates a close-up cross-sectional view of a V-shaped groove 131 and grit material 141 disposed primarily on intermediate spaces 132 between said grooves 131. It is noted how an overhang 142 of grit material 141 is formed, such that free space is provided between the slopes of the groove and said grit material 141.
REFERENCE NUMBERS
[0062] E Entering direction of product
[0063] L Central axis
[0064] 1 Angle relative to x-direction
[0065] 100 Abrading wheel
[0066] 101 Circular core
[0067] 103 Outer periphery
[0068] 105 Central aperture
[0069] 107 Indentation
[0070] 109 Depression
[0071] 111 Rim
[0072] 113 Outer surface
[0073] 115 Inner surface
[0074] 121 Openings
[0075] 123 Tongues
[0076] 124 Uncut edge
[0077] 131 Grooves
[0078] 132 Spaces
[0079] 133 End of groove 131
[0080] 141 Grit material
[0081] 142 Overhang
[0082] 150 Impact area
[0083] 150a Cathetus
[0084] 150c Hypotenuse
[0085] 221 Edge
[0086] 222 Edge
[0087] 223 Edge
