Rotary Dresser

Abstract

To provide a rotary dresser that is able to perform stable dressing with less resistance in dressing and less variation in sharpness.SOLUTION: A rotary dresser 100 is provided with a dressing part 50 having: an annular backing layer 30 projected in a flange shape on an outer peripheral surface 10a of a disk-like base metal 10; and an annular abrasive grain layer 20 formed on a rotating surface of the backing layer 30. In the rotary dresser 100, the abrasive grain layer 20 includes: an abrasive grain part 23 containing diamond abrasive grains fixed by plating; and a groove 24 formed so as to extend inward from an outer periphery of the abrasive grain layer 20; wherein a width of the groove 24 is 1 / 4 or more of an average particle diameter of the diamond abrasive grains and 18 times or less of the average particle diameter of the diamond abrasive grains.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This invention relates to a rotary dresser used for dressing general grinding wheels, CBN grinding wheels, and the like. [Background technology]

[0002] While various shapes and functions of rotary dressers have been proposed in the past, one example related to the present invention is the "rotary dresser" described in Patent Document 1. This "rotary dresser" is characterized by mixing diamond abrasive grains and inorganic particles and filling the inner surface of the mold, temporarily fixing one layer to the inner surface of the mold by electroplating, removing the excess diamond abrasive grains and inorganic particles, further fixing the diamond abrasive grains and inorganic particles by electroforming using electroplating, fixing an iron core to the center of the mold, and then removing the mold.

[0003] The aforementioned "rotary dresser" has the advantage of being able to arbitrarily adjust the concentration of diamond abrasive grains and widen the spacing between diamond abrasive grains, which makes it easier to cut into the grinding wheel, reduces resistance during dressing, widens the spacing between abrasive grains on the grinding wheel surface, reduces grinding resistance between the abrasive grains and the workpiece, and enables good grinding. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-174429 [Overview of the project] [Problems that the invention aims to solve]

[0005] While the rotary dresser described in Patent Document 1 has the advantages mentioned above, it suffers from inconsistencies in cutting performance due to factors such as uneven distribution of abrasive grains on the dressing surface and the misalignment of the abrasive grains' wear resistance direction relative to the direction of use. As a result, the surface condition of the dressed grinding wheel is unstable, and defects often occur in the shape and surface roughness of the workpiece cut by the dressed grinding wheel.

[0006] On the other hand, increasing the number of abrasive grains on the dresser surface tends to increase the contact area and thus increase resistance during dressing.

[0007] Therefore, the problem that the present invention aims to solve is to provide a rotary dresser that can perform stable dressing with less resistance during dressing and less variation in cutting performance. [Means for solving the problem]

[0008] The first rotary dresser according to the present invention is a rotary dresser comprising a dressing portion having a fixed portion on which an abrasive layer is provided, and the abrasive layer having an abrasive portion containing diamond abrasive grains fixed by plating and a groove portion containing grooves, wherein the width of the groove is 1 / 4 or more of the average particle size of the diamond abrasive grains and 18 times or less of the average particle size of the diamond abrasive grains, the fixed portion is an annular backing layer projecting in a flange-like manner from the outer circumferential surface of a base metal having a disc-shaped portion, the abrasive layer is an annular abrasive layer formed on the rotating surface of the backing layer, and the groove is formed to extend inward from the outer circumferential surface of the abrasive layer.

[0009] Furthermore, the second rotary dresser according to the present invention is a rotary dresser comprising a dressing portion having a fixed portion on which an abrasive layer is provided, and the abrasive layer having an abrasive portion containing diamond abrasive grains fixed by plating and a groove portion containing grooves, wherein the width of the groove is 1 / 4 or more of the average particle size of the diamond abrasive grains and 18 times or less of the average particle size of the diamond abrasive grains, the fixed portion is a cylindrical projection having the same axis as a base metal having a cylindrical portion and projecting outwards to one side in the axial direction of the base metal, the abrasive layer is a cylindrical abrasive layer formed on the outer circumferential surface of the projection, and the groove is formed to extend from the working surface toward the base metal side.

[0010] By using a configuration such as the first rotary dresser or the second rotary dresser, the increase in resistance during dressing can be suppressed even when the number of diamond abrasive grains is densely arranged. This reduces resistance during dressing and enables stable dressing with less variation in cutting performance.

[0011] In the first rotary dresser and the second rotary dresser, it is preferable that the total exposed area (projected area) of the diamond abrasive grains relative to the area of ​​the working surface of the abrasive grain layer excluding the groove portion is between 7% and 71%. In this way, by making the diamond abrasive grains denser in the abrasive section, variations in cutting performance can be reduced, and the surface condition of the dressed section can be stabilized.

[0012] In the first rotary dresser and the second rotary dresser, when the intergrain distance between adjacent diamond abrasive grains is determined in the usable portion, excluding the grooves in the outermost layer of the abrasive grain layer in the axial direction, it is preferable that 90% or more of the intergrain distance is 2 / 3 times or more the average particle size of the diamond abrasive grain and 3 times or less the average particle size of the diamond abrasive grain. Furthermore, when the intergrain distance between adjacent diamond abrasive grains is determined in the usable portion, excluding the grooves in the outermost layer of the abrasive grain layer in the normal direction, it is preferable that 90% or more of the intergrain distance is 2 / 3 times or more the average particle size of the diamond abrasive grain and 3 times or less the average particle size of the diamond abrasive grain. By configuring the spacing between abrasive grains in this way, variations in cutting performance are suppressed until the very end of use, and the surface condition of the dressed area is kept stable while dressing.

[0013] In the first rotary dresser and the second rotary dresser, if the theoretical number of diamond abrasive grains that can exist along the outer surface excluding the grooves in the abrasive grain layer is X, and the number of diamond abrasive grains that exist along the outer surface excluding the grooves is N, then it is preferable that 0.6 × X ≤ N ≤ X. In this way, by making the diamond abrasive grains denser in the abrasive section, variations in cutting performance can be reduced, and the surface condition of the dressed section can be stabilized.

[0014] In the first rotary dresser and the second rotary dresser, the grooves are provided at intervals equal to or greater than the average particle size of the diamond abrasive grains in the tangential direction of the outer circumference of the abrasive grain layer, and it is preferable that the length of the grooves in the direction perpendicular to the working surface of the abrasive grain layer is 0.7 times or more the length of the abrasive grain layer in the direction perpendicular to the working surface. The formation of these grooves allows for further reduction of dressing resistance and the creation of more efficient abrasive cutting edges on the grinding wheel side.

[0015] The first rotary dresser and the second rotary dresser preferably have an average particle size of diamond abrasive grains of 70 μm or more and 1000 μm or less, and the shape of the diamond abrasive grains is preferably a hexa-octahedral shape and / or a truncated octahedral shape. Diamond abrasive grains of this shape are preferable because they allow for a dense arrangement of diamond abrasive grains within the abrasive layer.

[0016] Preferably, the first rotary dresser and the second rotary dresser have a fixed portion that is 0.1 mm or more and 2.0 mm or less in diameter, and the outer diameter of the rotary dresser is 10 mm or more and 300 mm or less.

[0017] Furthermore, in the first rotary dresser, the groove has a pair of parallel side surfaces and a bottom surface parallel to the rotating surface of the backing layer, and it is preferable that the groove is formed along a line connecting the outer circumference of the abrasive layer to the axis of the base metal, or is formed at an inclination with respect to the line connecting the outer circumference of the abrasive layer to the axis of the base metal. This groove configuration improves the efficiency of chip evacuation.

[0018] Furthermore, in the second rotary dresser, it is preferable that the groove has a pair of parallel side surfaces and a bottom surface parallel to the outer circumferential surface of the protrusion, and that the groove is formed to extend in a direction parallel to the axis or in a twisting direction. This groove configuration improves the efficiency of chip evacuation. [Effects of the Invention]

[0019] The present invention provides a rotary dresser that offers less resistance during dressing, less variation in cutting performance, and stable dressing. [Brief explanation of the drawing]

[0020] [Figure 1] This is a partially omitted perspective view showing a first rotary dresser, which is an embodiment of the present invention. [Figure 2]This is a partially abbreviated front view of the first rotary dresser, as seen from the direction of the arrow X in Figure 1. [Figure 3] This is a partially abbreviated cross-sectional view of the cross-section along the YY line in Figure 2. [Figure 4] This is a simplified schematic diagram showing the outer surface of the dressing section of the first rotary dresser. [Figure 5] This is a simplified schematic diagram showing the outer surface of the dressing section of the first rotary dresser. [Figure 6] This is an enlarged schematic diagram showing a simplified portion of Figure 2. [Figure 7] This diagram illustrates the distance between adjacent diamond abrasive grains. [Figure 8] This is a partially omitted front view of a first rotary dresser, which is another embodiment of the present invention. [Figure 9] This is a schematic diagram showing a simplified part of the first rotary dresser, which is another embodiment of the present invention. [Figure 10] This is a schematic diagram showing a simplified part of the first rotary dresser, which is another embodiment of the present invention. [Figure 11] This is a partially omitted perspective view showing a second rotary dresser, which is another embodiment of the present invention. [Figure 12] Figure 11 is a partially abbreviated plan view of the second rotary dresser. [Figure 13] Figure 11 is a partially abbreviated front view of the second rotary dresser. [Figure 14] This is a partially abbreviated end view of the cross-section along the Y2-Y2 line in Figure 12. [Figure 15] This is a simplified schematic diagram showing the working surface of the dressing section of the second rotary dresser. [Figure 16] This is a schematic diagram showing the process of dressing a grinding wheel using a rotary dresser. [Figure 17] This is a schematic diagram showing the process of grinding a workpiece with a grinding wheel dressed by a rotary dresser. [Figure 18]Figure 17 is a schematic diagram showing the grinding process of the workpiece during the grinding operation. [Modes for carrying out the invention]

[0021] Hereinafter, rotary dressers 100 to 102,200, which are embodiments of the present invention, will be described based on Figures 1 to 15. Note that the rotary dressers 100 to 102,200 described later are illustrative examples of the rotary dressers according to the present invention, and the rotary dressers according to the present invention are not limited to these rotary dressers 100 to 102,200. Also, common parts in rotary dressers 100 to 102,200 are denoted by the same reference numerals and their descriptions are omitted.

[0022] Furthermore, in this application, as shown in Figures 1 and 11, the direction of arrow a is the normal direction (sometimes simply referred to as "normal direction") of the outer circumferential surface of the dressing portion (outer circumferential surface of the abrasive layer). The direction of arrow b is the tangential direction (sometimes simply referred to as "tangential direction") of the outer circumferential surface of the dressing portion (outer circumferential surface of the abrasive layer). The direction of arrow c is the axial direction (sometimes simply referred to as "axial direction") of the base metal.

[0023] First, the first rotary dresser of the present invention will be described using rotary dressers 100 to 102 as examples. In the first rotary dresser of the present invention, the outer surface of the dressing part serves as the working surface, and dressing is performed by pressing the outer surface of the dressing part (working surface) against the object to be dressed (grinding wheel) while rotating the base metal. The stacking direction of the diamond abrasive grains is axial.

[0024] <Embodiment 1> The rotary dresser 100 shown in Figures 1 to 7 comprises an annular dressing section 50 having an annular backing layer 30 projecting in a flange-like manner from the outer circumferential surface 10a of a disc-shaped base metal 10, and an annular abrasive layer 20 formed on the rotating surface 30b of the backing layer 30 (see Figures 1 and 3). The outer diameter (D) of the rotary dresser 100 (diameter viewed from the axial direction (direction of arrow c), see Figure 2) is between 10 mm and 300 mm.

[0025] [Dress Department] The dressing portion 50 is annular when viewed from the axial direction. When viewed from the axial direction, the length obtained by subtracting the inner circumference from the outer circumference of the dressing portion 50 (L 50 (See Figure 2) is 1 to 14 mm, but is not limited to this. The usable area of ​​the rotary dresser 100 is approximately 5 / 7 of the outer circumference of the dressing section 50 in the direction normal to it.

[0026] Furthermore, the thickness of the dressing portion 50 is 0.45 to 3.00 mm. Since the abrasive grains are fixed by plating, in this invention, it is also possible to make the dressing portion 50 a thin layer of less than 1.00 mm (e.g., 0.45 to 0.98 mm).

[0027] [Backing layer] The backing layer 30 is a flange-like projection on the outer circumferential surface 10a of the disc-shaped base metal 10, and is integrally molded with the base metal 10. The thickness (T3) of the backing layer 30 is determined according to the characteristics of the dressed portion, but is between 0.1 mm and 2.0 mm (see Figure 5). A thicker backing layer 30 tends to reduce cutting performance. Depending on the specifications, the thickness of the backing layer 30 is adjusted as appropriate to 0.1 mm or more, 1 mm or more, 0.5 mm or less, etc.

[0028] [Abrasive layer] As shown in Figures 1 to 4, the abrasive layer 20 is an annular layer formed on the rotating surface 30b of the backing layer 30, and contains nickel plating and diamond abrasive grains 23A. The abrasive layer 20 has abrasive grain portions 23 containing diamond abrasive grains 23A fixed by nickel plating, and a plurality of groove portions consisting of grooves 24.

[0029] (Abrasive part) The abrasive grain portion 23 is an area of ​​the abrasive grain layer 20 other than the grooves (grooves 24), and contains diamond abrasive grains 23A fixed by nickel plating. The abrasive grain portion 23 also has a base region 23B formed by nickel plating, and the diamond abrasive grains 23A are fixed on top of the base region 23B. The diamond abrasive grains 23A are fixed to the backing layer 30 via the base region 23B, which improves adhesion and allows for stable fixing.

[0030] (Diamond abrasive particles) In the rotary dresser 100, the diamond abrasive grains 23A are arranged in a single layer and fixed by nickel plating. The average particle size (d) of the diamond abrasive grains 23A is 70 μm to 1000 μm, but is not limited to this range. The average particle size (d) of the diamond abrasive grains 23A is the average value of the particle sizes of 100 arbitrary diamond abrasive grains. The particle size of each diamond abrasive grain is the average value of the major and minor axes of the abrasive grain. For example, the major and minor axes (the long and short sides of the rectangle circumscribing the diamond abrasive grain) of the diamond abrasive grain can be determined from an image of the working surface taken with an image measuring machine, and the particle size can be calculated.

[0031] Furthermore, the diamond abrasive grains 23A are preferably hexa-octahedral and / or truncated octahedral in shape. Such shapes allow for dense arrangement of the abrasive grains. A truncated octahedral shape is a shape in which the vicinity of six vertices of a regular octahedral diamond abrasive grain is cut off in a square pyramidal shape, forming six square-shaped planar portions, consisting of six square faces and eight hexagonal faces. A hexa-octahedral shape is a shape in which the six square-shaped planar portions of a truncated octahedral shape are each equally extended until the vertices of adjacent square-shaped planar portions coincide, and a hexa-octahedron consists of six square faces and eight triangular faces. Furthermore, if the diamond abrasive grains 23A fixed to the backing layer 30 are fixed so that the flat portion of the diamond abrasive grains 23A is parallel to the rotating surface 30b of the backing layer 30, more stable dressing can be achieved. Therefore, it is preferable that the more diamond abrasive grains 23A are fixed in this manner (for example, 50% or more of the total number of abrasive grains). In particular, it is preferable that the more diamond abrasive grains 23A are fixed so that the flat portion having the largest surface area on the outer surface of the diamond abrasive grain 23A is parallel to the rotating surface 30b of the backing layer 30. That is, if the diamond abrasive grains 23A are hexagonal or octahedral in shape, it is preferable that the more diamond abrasive grains 23A are fixed so that the square faces are parallel to the rotating surface 30b of the backing layer 30, and if they are truncated octahedral in shape, it is preferable that the more diamond abrasive grains 23A are fixed so that the hexagonal faces are parallel to the rotating surface 30b of the backing layer 30.

[0032] As shown in Figure 5, in the rotary dresser 100, the thickness of the nickel plating (T) that fixes the diamond abrasive grains 23A in the axial direction. N ) Average value (T Na ) is the thickness from the backing layer 30 to the tip of the diamond abrasive grain 23A (T D ) Average value (T Da ) is 95%. Here, the thickness of the nickel plating (T N ) Average value (T Na ) is the thickness of the nickel plating (T) of the abrasive grain portion 23 on the outer peripheral surface 20a. N) is the value obtained by measuring eight points and averaging. The thickness (T D ) of the average value (T Da ) is, on the outer peripheral surface 20a, the thickness (T D ) from the backing layer 30 to the tip of the diamond abrasive grains 23A, which is the value obtained by measuring eight points and averaging. Each T N and T D can be measured using a microscope such as a digital microscope.

[0033] Note that the nickel plating can be adjusted to any thickness as long as it can fix the diamond abrasive grains 23A, but if the nickel plating is too thin, it is in the direction where the fixation of the diamond abrasive grains 23A becomes unstable. Therefore, assuming the average particle size of the diamond abrasive grains 23A is d and the number of stacked layers of the diamond abrasive grains 23A is n, the average value (T N ) of the thickness (T Na ) of the nickel plating is preferably n×d×0.95 or more. Since the rotary dresser 100 has a stacking number of 1, the average value (T N ) of the thickness (T Na ) of the nickel plating is preferably d×0.95 or more.

[0034] In the abrasive grain portion 23, the diamond abrasive grains 23A are preferably arranged densely. Therefore, assuming the theoretical number of diamond abrasive grains 23A that can exist along the outer peripheral surface of the abrasive grain portion 23 (the outer peripheral surface excluding the groove 24 portion of the abrasive grain layer 20) is X and the number of diamond abrasive grains 23A existing along the outer periphery of the abrasive grain portion 23 is N, 0.6×X≦N≦X is preferable. This N can be arbitrarily adjusted to 0.99×X or less, 0.97×X or less, 0.7×X or more, 0.8×X or more, 0.85×X or more, etc. according to the particle size of the diamond abrasive grains 23A. The theoretical number X is calculated by taking the length (circumference) of the outer periphery of the abrasive grain layer 20 as L C , the average particle size of the diamond abrasive grains 23A as d, and the total width of the grooves 24 as W 24 as W 24t , then X=(L C - W 24t ) / d=(π×D - W 24tIt is expressed as ) / d. The groove width and the number of diamond abrasive grains 23A can be measured using a microscope, such as a digital microscope.

[0035] Furthermore, the total exposed area (projected area) of the diamond abrasive grains 23A relative to the area of ​​the region of the working surface (outer surface 20a) of the abrasive grain layer 20 excluding the grooves 24 (total area of ​​the outer surface of the abrasive grain portion 23) is preferably 7% to 71%, but may also be 35% to 68%, or 50% to 65%. For example, this can be calculated by photographing the entire outer surface 20a of the abrasive grain layer 20 excluding the grooves 24 with a microscope such as a digital microscope, and then processing the captured image into a binarized image.

[0036] Furthermore, in the usable portion, excluding the grooves in the outermost layer of the abrasive grain layer in the axial direction, the distance between adjacent diamond abrasive grains (L X When the abrasive grain distance (L) (see Figure 7) is determined, 90% or more of it is the inter-grain distance (L) X Preferably, the intergrain distance (L) is 2 / 3 times or more the average grain size (d) of the diamond abrasive grains and 3 times or less the average grain size (d) of the diamond abrasive grains (i.e., d × 2 / 3 to d × 3). The larger the proportion of intergrain distances (L) that are d × 2 / 3 to d × 3, the more sustained and stable grinding can be achieved. The outermost layer in the axial direction of the abrasive layer is the nth layer when the number of layers of diamond abrasive grains in the abrasive layer is n (for example, 1 ≤ n ≤ 5). Since the rotary dresser 100 has 1 layer of diamond abrasive grains 23A, in the usable portion, the intergrain distance (L) of adjacent diamond abrasive grains 23A is limited to the groove 24 portion of the first layer of the abrasive layer 20. X When the abrasive grain distance (L) of 90% or more is determined, X Preferably, the particle size is 2 / 3 or more the average particle size of the diamond abrasive grains 23A, and 3 times or less the average particle size of the diamond abrasive grains 23A.

[0037] Furthermore, in the usable portion, excluding the grooves of the outermost layer in the direction normal to the abrasive grain layer (outer surface 20a in the rotary dresser 100), the distance between adjacent diamond abrasive grains (L XWhen the abrasive grain distance (L) of 90% or more is determined, X Preferably, the intergrain spacing (L) is 2 / 3 times or more the average grain size of the diamond abrasive grains, and 3 times or less the average grain size of the diamond abrasive grains. The larger the proportion of intergrain spacing (L) that is d×2 / 3 to d×3, the more diamond abrasive grains 23A can be used for grinding.

[0038] Note that the distance between adjacent diamond abrasive grains (L X The distance between adjacent diamond abrasive grains (L) is the distance between adjacent diamond abrasive grains in the portion of the abrasive layer excluding the grooves, and does not include the distance between adjacent diamond abrasive grains across areas other than the abrasive grain portion, such as grooves. Specifically, as shown in Figure 7, the distance between abrasive grains (L) is the distance between adjacent diamond abrasive grains (L) X The inter-grain distance (L) is defined as the distance between two adjacent diamond abrasive grains 23A-1 and 23A-2, connecting the center of the circumscribed circle around one diamond abrasive grain 23A-1 and the center of the circumscribed circle around the other diamond abrasive grain 23A-2 adjacent to the first diamond abrasive grain 23A-1. X For example, this can be calculated by using a microscope such as a digital microscope to photograph the entire usable area while the nth layer of diamond abrasive grains in the axial or normal direction of the abrasive layer is visible, and then processing the captured image by binarizing it.

[0039] (groove) As shown in Figure 2, the abrasive layer 20 has multiple grooves 24 extending inward from the outer circumference. Each groove 24 has a pair of parallel side surfaces and a bottom surface parallel to the rotational surface 30b of the backing layer 30, and is formed in the same shape. They are provided at equal intervals with spacing greater than or equal to the average particle size (d) of the diamond abrasive grains 23A in the tangential direction of the outer circumference of the abrasive layer 20 (outer circumference of the dressing portion 50). The spacing of the grooves 24 can be adjusted arbitrarily, but if the spacing of the grooves 24 is too narrow, the number of diamond abrasive grains 23A will decrease, which may shorten the lifespan of the rotary dresser depending on the operating conditions and environment. For this reason, the width of the abrasive portion 23 is set to W 23 The width of groove 24 is W 24 Therefore, d≦W 23 ≤(π×D-8×W) 24It is preferable that the ratio is ) / 8 (see Figure 5). The shape of the grooves 24 (width, length, thickness) and the spacing between the grooves 24 (width of the abrasive grain portion 23) can be measured using a microscope such as a digital microscope.

[0040] Width of groove 24 (W 24 The width of the groove (W) is 1 / 4 or more of the average particle size (d) of the diamond abrasive grains 23A and 18 times or less of the average particle size (d) of the diamond abrasive grains 23A (see Figure 5). 24 If the groove width (W) is smaller than 1 / 4 of the average particle size (d) of the diamond abrasive grains 23A, the dressing resistance increases and the effects of the present invention cannot be obtained. Also, if the groove width (W) is smaller, the dressing resistance increases and the effects of the present invention cannot be obtained. 24 If the average particle size (d) of the diamond abrasive grains 23A is greater than 18 times, the abrasive portion containing the diamond abrasive grains will decrease, resulting in a rougher surface finish on the workpiece after dressing, making stable dressing impossible and shortening the lifespan of the rotary dresser.

[0041] Width of groove 24 (W 24 The particle size (d) is preferably 1 / 3 to 15 times the average particle size (d) of the diamond abrasive grains 23A, more preferably 1 / 2 to 10 times the average particle size (d) of the diamond abrasive grains 23A, and even more preferably 3 / 4 to 5 times the average particle size (d) of the diamond abrasive grains 23A.

[0042] Furthermore, the grooves 24 are formed radially along the line Z connecting the outer circumference of the abrasive layer 20 to the axis R of the base metal 10 (see Figure 2). The length of the grooves 24 in the direction perpendicular to the working surface of the abrasive layer 20 (i.e., the length of the grooves 24 in the normal direction (L) 24 The length (L) of the abrasive layer 20 in the direction perpendicular to the working surface is preferably greater than or equal to the usage allowance. Specifically, the length (L) of the abrasive layer 20 in the direction perpendicular to the working surface is preferably greater than or equal to the usage allowance. 20 )(that is, the length from the outer circumference to the inner circumference of the dressing portion 50 (abrasive layer 20) (L 50 )) 0.7 times or more (L 24 ≥0.7 × L 20 ) is preferable.

[0043] In the axial direction, as shown in Figures 4 and 5, the groove 24 is formed to extend to the backing layer 30. When viewed from the normal direction (direction of arrow a), the shape of the groove 24 is rectangular. Note that, as shown in Figures 9 and 10 later, the groove does not extend to the backing layer, and the groove portion may have a sub-groove region formed by nickel plating on the lower side of the groove, and the groove depth (length of the groove in the axial direction, T) 24 ) is the thickness of the nickel plating (T N ) Average value (T Na The value may be greater than 0 times and less than or equal to 1 times, for example, 0.1 to 1 times or 0.5 to 1 times. Also, the shape of the groove when viewed from the normal direction may be a quadrilateral other than a rectangle, such as a square or trapezoid.

[0044] Furthermore, if the shape of the abrasive grain portion 23 or groove 24 when viewed from the normal direction is not rectangular or square (i.e., if the pair of sides are not parallel), the width of each (W) 23 ,W 24 The length of the abrasive grain portion 23 shall be the maximum length in the tangential direction. Also, if the thickness (length in the axial direction) is not constant, the nickel plating thickness (T N ), thickness from the backing layer 30 to the tip of the diamond abrasive grain 23A (T D ) and the depth of groove 24 (T 24 ) shall be the maximum length in the axial direction, and if the length of groove 24 (length in the normal direction) is not constant, the length of groove 24 (L 24 ) is the maximum length in the normal direction.

[0045] The rotary dresser 100 can be manufactured using methods such as: forming a base region 23B after masking the area where the groove 24 is to be formed on the backing layer 30 to prevent the deposition of plating metal, and then arranging diamond abrasive grains 23A on the base region 23B while applying vibration to perform the plating process; forming a base region 23B on the backing layer 30, masking the area where the groove 24 is to be formed to prevent the deposition of plating metal, and then arranging diamond abrasive grains 23A on the base region 23B while applying vibration to perform the plating process; or forming a base region 23B on the backing layer 30, then arranging diamond abrasive grains 23A while applying vibration to perform the plating process, and then forming the groove 24. By arranging (filling) the diamond abrasive grains 23A on the backing layer 30 via the base region 23B while applying vibration, it is easy to arrange them densely, and furthermore, it is easy to arrange the diamond abrasive grains 23A so that the flat parts (especially the flat parts with the largest area) are parallel to the rotating surface 30b of the backing layer 30, rather than the edges. Furthermore, the manufacturing method of the rotary dresser 100 is not limited to these methods.

[0046] <Embodiment 2> The rotary dresser 101 shown in Figures 8 and 9 comprises an annular dressing section 51 having a backing layer 30 and an annular abrasive layer 21 formed on the rotating surface 30b of the backing layer 30. The abrasive layer 21 has an abrasive section 23 containing a base region 23B formed by nickel plating and diamond abrasive grains 23A fixed by nickel plating, and a plurality of groove sections 25 consisting of grooves 25A and a sub-groove region 25B. The sub-groove region 25B is the region below the groove 25A in the axial direction (direction of arrow c) and is formed by nickel plating.

[0047] Each groove 25A is formed in the same shape and is inclined with respect to the line Z connecting the outer circumference to the axis of the base metal 10, forming a helical shape. Spacing of grooves 25A (width of abrasive grain portion 23 (W) 23 )) and width (W 25 The length of groove 25A in the direction normal to groove 24 is the same as that of groove 24. 25 ) is preferably greater than or equal to the usage allowance, for example, the length from the outer circumference to the inner circumference of the abrasive layer 21 (L21 It is more than 0.7 times the depth of groove 25A (T 25 ) is the thickness of the nickel plating (T N ) Average value (T Na ) is smaller than, and the groove 25A does not penetrate through to the backing layer 30 in the axial direction, for example, T Na ×0.1~T Na It is multiplied by 0.95.

[0048] The abrasive layer 21 has a nickel plating thickness (T) to which the diamond abrasive grains 23A are fixed. N ) Average value (T Na ) is the thickness from the backing layer 30 to the tip of the diamond abrasive grain 23A (T D ) Average value (T Da ) is thicker than T. Da <T Na ≤1.5 × T Da Yes, 1.1×T Da ≦T Na ≤1.4 × T Da Therefore, in the rotary dresser 101, nickel plating is applied so as to completely cover the diamond abrasive grains 23A in the axial direction. By applying nickel plating so as to completely cover the diamond abrasive grains 23A, the diamond abrasive grains 23A can be fixed more stably. On the other hand, if the nickel plating is too thick, the cutting performance tends to decrease. Therefore, if the average particle size of the diamond abrasive grains 23A is d and the number of layers of diamond abrasive grains 23A is n, then the thickness of the nickel plating (T N ) Average value (T Na ) is preferably n × d + 0.5 × d or less. Since the rotary dresser 101 has 1 layer, the thickness of the nickel plating (T N ) Average value (T Na ) is preferably d × 1.5 or less.

[0049] <Embodiment 3> The rotary dresser 102 shown in Figure 10 comprises a backing layer 30 and an annular dressing portion 52 having an annular abrasive layer 22 formed on the rotating surface 30b of the backing layer 30.

[0050] The abrasive layer 22 has abrasive grain portions 27 and multiple groove portions 28 consisting of grooves 28A and groove-sub-groove regions 28B. The groove-sub-groove region 28B is the region axially below the groove 28A and is formed by nickel plating. The abrasive grain portion 27 is the same as the abrasive grain portion 23 except that five layers of diamond abrasive grains 23A are arranged axially via a base region 27B and fixed by nickel plating. The layered structure improves wear resistance. Nickel plating thickness (T N ) Average value (T Na ) is the thickness from the backing layer 30 to the tip of the diamond abrasive grain 23A in the 5th layer (T D ) Average value (T Da ) is thicker than (i.e., T Da <T Na ) is not limited to this, and the thickness of the nickel plating (T N ) Average value (T Na The depth of the grooves is approximately 5d × 0.95 to 5.5 × d. The grooves 28A are formed radially along the line Z connecting the outer circumference of the abrasive layer 22 to the axis R of the base metal 10. In the groove portion 28, the grooves 28A do not extend to the backing layer 30 and have a groove-lower region 28B, however the grooves 28A may extend to the backing layer 30, and the depth of the grooves 28A (T 28 ) and width (W 28 ), the length is the same as that of groove 24.

[0051] Furthermore, the number of layers (n) of diamond abrasive particles is not limited to 5; the number of layers can range from 1 to 5.

[0052] Next, the second rotary dresser of the present invention will be described. The second rotary dresser of the present invention is a so-called cup-type dresser in which the end face of the dressing portion perpendicular to the axial direction becomes the working surface, and dressing is performed by pressing the end face of the dressing portion perpendicular to the axial direction against the object to be dressed (grinding wheel) while rotating the base metal. In addition, the stacking direction of the diamond abrasive grains is the normal direction.

[0053] <Embodiment 4> The rotary dresser 200 shown in FIGS. 11 to 15 includes a base metal 60 and a cylindrical dressing portion 62 provided at one axial end of the base metal 60. The outer diameter (D) of the rotary dresser 200 is 10 to 300 mm.

[0054] [Dressing portion] The dressing portion 62 has a protruding portion 80 and a cylindrical abrasive grain layer 70 formed on the outer peripheral surface 80a of the protruding portion 80. The axial length of the dressing portion 62 (the distance from the working surface to the base metal, L 62 ) is 1 to 14 mm, but is not limited thereto. The usage cost of the rotary dresser 200 is about 5 / 7 of the dressing portion 62. Also, the thickness of the dressing portion 62 (the length in the normal direction, T 62 ) is 0.45 to 3.00 mm. In order to fix the abrasive grains by plating, in the present invention, it is also possible to make the thickness of the dressing portion 62 a thin layer of less than 1.00 mm (such as 0.45 to 0.98 mm).

[0055] [Protruding portion] The protruding portion 80 is a cylindrical portion protruding in one axial direction of the base metal 60, is integrally formed with the base metal 60, and has the same axis R as the base metal 60. As shown in FIG. 14, the base metal 60 has a cylindrical portion 60B whose outer peripheral surface is cylindrical and a convex portion 60A protruding from one end surface of the cylindrical portion 60B. The protruding portion 80 is formed on the outer peripheral side on the convex portion 60A (on the side opposite to the cylindrical portion 60B), and the outer peripheral surface 60a of the convex portion 60A and the outer peripheral surface 80a of the protruding portion 80 are located on the same surface. The thickness of the protruding portion 80 (the length in the normal direction, T 80 ) is determined according to the mode of the dressing portion and the like, but is 0.1 mm to 2.0 mm. When the thickness of the protruding portion 80 is thick, the cutting edge tends to deteriorate. Depending on the specifications, the thickness of the protruding portion 80 is appropriately adjusted to be 0.1 mm or more, 1 mm or more, 0.5 mm or less, etc.

[0056] [Abrasive grain layer] As shown in Figure 11, the abrasive layer 70 is a cylindrical layer formed on the outer circumferential surface 80a of the protrusion 80. A groove 74 is formed on the outer circumferential surface 70a of the abrasive layer 70, extending from the working surface 70b (the surface perpendicular to the axis) toward the base metal side. The abrasive layer 70 has a plurality of grooves consisting of abrasive portions 73 containing diamond abrasive grains 73A fixed by nickel plating and grooves 74. Furthermore, as shown in Figure 14, the abrasive layer 70 is formed from the outer circumferential surface 80a of the protrusion 80 to the outer circumferential surface 60a of the convex portion 60A of the base metal 60.

[0057] (Abrasive part) The abrasive portion 73 is the region of the abrasive layer 70 other than the grooves (grooves 74), and contains diamond abrasive grains 73A fixed by nickel plating (see Figure 15). The abrasive portion 73 also has a base region 73B formed by nickel plating, and the diamond abrasive grains 73A are fixed on top of the base region 73B.

[0058] (Diamond abrasive particles) The diamond abrasive grains 73A are arranged in a single layer along the outer circumference of the protrusion 80 via the base region 73B and fixed by nickel plating. However, the number of layers of diamond abrasive grains 73A is not limited to one, and the number of layers n can be 1 to 5. It is preferable that the diamond abrasive grains 73A are densely arranged in the abrasive grain portion 73. The diamond abrasive grains 73A can be the same as those used for the diamond abrasive grains 23A of the first rotary dresser, and it is preferable that the average particle size (d) is 70 μm to 1000 μm and that they have a hexa-octahedral shape and / or a truncated octahedral shape.

[0059] In the rotary dresser 200, the thickness of the nickel plating that fixes the diamond abrasive grains 73A in the normal direction (T N ) Average value (T Na ) is the thickness (T) from the protruding part 80 to the tip of the diamond abrasive grain 73A. D ) Average value (T Da ) is between 95% and 150%.

[0060] Furthermore, the thickness of the nickel plating that fixes the diamond abrasive grains 73A (TN ) The average value (T Na ) can be arbitrarily adjusted, but if the nickel plating is too thin, it will be in a direction where the fixation of the diamond abrasive grains 73A becomes unstable, and if it is too thick, it will be in a direction where the cutting performance deteriorates. Therefore, assuming that the average particle size of the diamond abrasive grains 73A is d and the number of layers of the diamond abrasive grains 73A in the normal direction is n, the thickness (T N ) The average value (T Na ) is preferably n×d×0.95 or more and preferably n×d + d×0.5 or less. Since the rotary dresser 200 has a lamination number of 1, the average value of the thickness (T N ) is preferably d×0.95 or more and d×1.5 or less.

[0061] The number of diamond abrasive grains 73A existing along the outer peripheral surface of the abrasive grain portion 73 (the outer peripheral surface excluding the groove 74 portion of the abrasive grain layer 70) is N, and the length (circumference) of the outer periphery of the abrasive grain layer 70 is L<^ c , the average particle size of the diamond abrasive grains 73A is d, and the total width of the grooves 74 is W 74 is W 74t Then, 0.6×(L c - W 74t ) / d ≦ N ≦ (L c - W 74t ) / d is preferable. (L c - W 74t ) / d is the theoretical number (X) of diamond abrasive grains 73A that can exist along the outer peripheral surface of the abrasive grain portion 73. Depending on the average particle size of the diamond abrasive grains 73A and the width of the groove 74, N / X can be arbitrarily adjusted to be 0.99 or less, 0.97 or less, 0.7 or more, 0.8 or more, 0.85 or more, etc.

[0062] The total exposed area of the diamond abrasive grains 73A with respect to the area of the region excluding the grooves 74 on the working surface 70b of the abrasive grain layer 70 is preferably 7 area% or more and 71 area% or less, and may be 35 to 68 area% or 50 to 65 area%, etc.

[0063] When determining the intergrain distance between adjacent diamond abrasive grains (the intergrain distance between adjacent diamond abrasive grains in the abrasive portion) in the usable portion, excluding the grooves of the outermost layer in the axial direction of the abrasive layer (the working surface 70b in the rotary dresser 200), it is preferable that 90% or more of these intergrain distances are 2 / 3 or more times the average particle size (d) of the diamond abrasive grains and 3 times or less the average particle size (d) of the diamond abrasive grains (i.e., d × 2 / 3 to d × 3). The larger the proportion of intergrain distances (L) that are d × 2 / 3 to d × 3, the more diamond abrasive grains 73A do work, thus further reducing variations in cutting performance.

[0064] When determining the intergrain distance between adjacent diamond abrasive grains in the abrasive portion, excluding the grooves of the outermost layer in the normal direction of the abrasive grain layer, it is preferable that 90% or more of these intergrain distances are at least 2 / 3 times the average particle size of the diamond abrasive grains and at least 3 times the average particle size of the diamond abrasive grains. The higher the proportion of intergrain distances (L) that are d × 2 / 3 to d × 3, the more sustained and stable grinding can be achieved, thus enabling stable grinding over a longer period of time. The outermost layer in the normal direction of the abrasive grain layer is the nth layer when the number of layers of diamond abrasive grains in the abrasive grain layer is n (for example, 1 ≤ n ≤ 5).

[0065] (groove) As shown in Figures 11 and 13, the abrasive layer 70 has multiple grooves 74 extending from the working surface 70b toward the base metal side. Each groove 74 has a pair of parallel side surfaces and a bottom surface parallel to the outer circumferential surface 80a of the protrusion 80, and is formed in the same shape, with the width (tangential length) of the abrasive portion 73 being W 73 Therefore, in the tangential direction of the outer circumference of the abrasive layer 70 (dressing portion 62), d≦W 73 ≤(π×D-8×W) 74 They are spaced at equal intervals, with a gap of ) / 8.

[0066] Width of groove 74 (length in the tangential direction, W) 74 The width of the groove (W) is 1 / 4 or more of the average particle size (d) of the diamond abrasive grains 73A and 18 times or less of the average particle size (d) of the diamond abrasive grains 73A (see Figure 15).74 If the width of the groove 74 (W) is less than d × 1 / 4, the dressing resistance increases, and the width of the groove 74 (W) 74 If d × 18 is greater than d, stable dressing cannot be performed, such as the surface roughness of the workpiece after dressing becoming rough, and therefore the effects of the present invention cannot be obtained. The width of the groove 74 is preferably 1 / 3 to 15 times the average particle size (d) of the diamond abrasive grains 73A, more preferably 1 / 2 to 10 times the average particle size (d) of the diamond abrasive grains 73A, and even more preferably 3 / 4 to 5 times the average particle size (d) of the diamond abrasive grains 73A.

[0067] Furthermore, the groove 74 is formed to extend in a direction parallel to the axis R (rotational axis). The length of the groove 74 in the axial direction (L 74 The length of groove 74 (L) is preferably greater than or equal to the usage allowance. Specifically, the length of groove 74 (L) 74 ) is the length (L) from the working surface 70b of the dressing part 62 to the base metal. 62 ) 0.7 times or more (0.7 × L 62 ≤L 74 ) is preferable.

[0068] As shown in Figure 15, in the normal direction, the groove 74 is formed to extend to the projection 80. When viewed from the axial direction, the shape of the groove 74 is approximately rectangular. Alternatively, the groove may not extend to the projection, and the groove portion may have a sub-groove region formed by nickel plating below the groove, and the groove depth (groove length in the normal direction, T) may be specified. 74 ) is the thickness of the nickel plating (T N ) Average value (T Na The ratio may be greater than 0 times and less than or equal to 1 times, for example, 0.1 to 1 times or 0.5 to 1 times. Also, the shape of the groove when viewed from the axial direction may be a roughly square or trapezoid, or a sector, depending on the width of the groove, other than a roughly rectangular shape.

[0069] If the shape of the abrasive grain portion 73 or groove 74 when viewed from the axial direction is not approximately rectangular or approximately square (i.e., if the pair of sides are not parallel), then the width of each (W 73 ,W 74The length of the abrasive grain portion 73 shall be the maximum length in the tangential direction. Also, if the thickness (length in the normal direction) is not constant, the nickel plating thickness (T) of the abrasive grain portion 73 shall be the maximum length. N ), thickness from the protruding part 80 to the tip of the diamond abrasive grain 73A (T D ) and the depth of groove 74 (T 74 ) shall be the maximum length in the normal direction, and if the length of groove 74 (axial length) is not constant, the length of groove 74 (L 74 ) is defined as the maximum length in the axial direction.

[0070] In the rotary dresser 200, the base plate 60 has a cylindrical portion 60B and a convex portion 60A, but the shape of the base plate is not limited to this and may be cylindrical or cup-shaped. Also, the groove 74 may be formed to extend in the twist direction with respect to the axis R (rotational axis). Furthermore, the measurement method for the configuration of the abrasive portion 73 (width, thickness, ratio of projected area of ​​diamond abrasive grains 73A, inter-grain distance, etc.) and the shape of the groove 74 (width, thickness, length, etc.) is the same as for the rotary dresser 100.

[0071] The method for manufacturing the rotary dresser 200 is not particularly limited, but examples include a method in which, after masking the position on the protruding portion 80 where the groove 74 is to be formed so that plating metal does not precipitate, a base region 73B is formed, and diamond abrasive grains 73A are arranged on the base region 73B while applying vibration to perform the plating process; a method in which a base region 73B is formed on the outer peripheral surface 80a of the protruding portion 80, masking the position where the plating metal is to be formed so that plating metal does not precipitate, and then diamond abrasive grains 73A are arranged while applying vibration to perform the plating process; and a method in which a base region 73B is formed on the outer peripheral surface 80a of the protruding portion 80, then diamond abrasive grains 73A are arranged while applying vibration to perform the plating process, and then the groove 74 is formed. [Examples]

[0072] <Rotary dresser used> A rotary dresser (wheel-type rotary dresser) was used, in which an abrasive layer was formed on the rotating surface of a backing layer that protruded in a flange-like manner from the outer circumference of a disc-shaped base metal. Rotary dressers of Examples 1-5 and Comparative Examples 1 and 2 were manufactured, with the same number of grooves but varying the width of the grooves, resulting in grooves of different widths arranged at equal intervals. A conventional rotary dresser without grooves was designated as Comparative Example 3.

[0073] In the manufacturing of the rotary dressers in Examples 1-5 and Comparative Examples 1 and 2, first, grooves of a predetermined width were formed at equal intervals on the base metal, which was integrally formed with the backing layer, by masking. Next, after applying nickel plating to the areas without masking, diamond abrasive grains were scattered and filled by applying vibration, arranging the diamond abrasive grains in a single layer. Furthermore, nickel plating was performed to electrodeposit and fix the diamond abrasive grains.

[0074] In the manufacturing of the rotary dresser in Comparative Example 3, a nickel-plated base layer was applied to the rotating surface of the backing layer. Diamond abrasive grains were scattered on the nickel-plated base layer to arrange the diamond abrasive grains in a single layer, and then nickel plating was performed to electrodeposit and fix the diamond abrasive grains.

[0075] The shape and other specifications of the manufactured rotary dresser are as follows: • Rotary dresser shape: Wheel shape Rotary dresser outer diameter: D(Φ)100mm • Dress portion length: 7mm • Dress thickness: 0.95mm • Nickel plating thickness: 0.85mm • Groove length: 5mm • Groove width: Shown in Table 1. • Diamond abrasive grains: Average particle size 650 μm, hexa-octahedron

[0076] [Table 1]

[0077] (Percentage of projected area of ​​diamond abrasive particles (%)) The outer surface of the abrasive layer of the rotary dressers in Examples 1-5 and Comparative Examples 1-3 was photographed with a digital microscope. The captured images were binarized to determine the area of ​​the abrasive portion containing diamond abrasive grains and the total area (exposed area) of the diamond abrasive grains. The ratio (%) of the total area of ​​the diamond abrasive grains to the area of ​​the abrasive portion was calculated and expressed as the ratio (%) of the projected area of ​​the diamond abrasive grains. The results are shown in Table 1.

[0078] (Percentage of the distance L between abrasive grains (%)) Using a digital microscope, the abrasive layers of the rotary dressers in Examples 1-5 and Comparative Examples 1-3 were observed from the direction of arrow a (normal direction), and the distance between abrasive grains (L) in the portion where two diamond abrasive grains are adjacent on the outer surface was determined. X The distance between abrasive grains (L) was calculated. X From within the given area, the number of portions having an intergrain distance L that satisfies the condition of being between 2 / 3 and 3 times the average grain size (d) of the diamond abrasive grains was determined. X The ratio (%) of the number of parts with an abrasive grain distance L to the number of parts for which the abrasive grain distance L was calculated was determined and this was taken as the ratio (%) of the abrasive grain distance L on the outer surface. Furthermore, using a digital microscope, the abrasive layers of the rotary dressers of Examples 1-5 and Comparative Examples 1-3 were observed from the direction of arrow c (axial direction), and for the usable portion, the distance between abrasive grains (L) in the portion where two diamond abrasive grains are adjacent on the abrasive grain portion of the surface perpendicular to the axial direction was determined. X The distance between abrasive grains (L) was calculated. X From within the given area, the number of portions having an intergrain distance L that satisfies the condition of being between 2 / 3 and 3 times the average grain size (d) of the diamond abrasive grains was determined. X The ratio (%) of the number of parts with an abrasive grain distance L to the number of parts for which the abrasive grain distance was calculated was determined, and this was taken as the ratio (%) of the abrasive grain distance L on the plane perpendicular to the axis. The results for each are shown in Table 1.

[0079] (N / X) Using a digital microscope, the number of diamond abrasive grains (N) present along the outer circumference of the abrasive layer of the rotary dressers in Examples 1-5 and Comparative Examples 1-3, excluding the groove portion, was determined. The theoretical number of diamond abrasive grains (X) that could exist along the outer circumference of the abrasive layer, excluding the groove portion, was determined from the groove width, the outer diameter of the dresser, and the average particle size of the diamond abrasive grains. N was divided by X to calculate N / X. The results are shown in Table 1.

[0080] <Dress Performance Comparison Test> First, the grinding wheel 2 was dressed using the rotary dresser 1 (the rotary dresser used in Examples 1-5 and Comparative Examples 1-3) according to the following dressing method. Next, the workpiece 4 was ground using the dressed grinding wheel 2 according to the following grinding method, and the cutting performance (power consumption), surface roughness, and stability during the grinding operation were evaluated.

[0081] (Dressing method) Figure 16 schematically shows the process of dressing the grinding wheel 2 using the rotary dresser 1. The dressing was performed wet using a horizontal-axis surface grinding machine, while supplying grinding fluid from the grinding fluid supply means 3. The dressing conditions were as follows: Peripheral speed ratio: 0.5 (Peripheral speed of grinding wheel 2: 40 m / sec, Peripheral speed of dresser: 20 m / sec) Dress lead: 0.2mm / rev Depth of cut: 0.010mm Grit size of whetstone: #80

[0082] (Grinding method) Figure 17 schematically shows the grinding of the workpiece 4 with a grinding wheel 2 dressed by a rotary dresser 1 (see Figure 16). Figure 18 schematically shows the grinding process of the workpiece in the grinding operation shown in Figure 17, with each of the arrows representing one pass. The grinding operation was performed wet using a horizontal-axis surface grinding machine, while supplying grinding fluid from the grinding fluid supply means 3. The grinding conditions were as follows: Grinding wheel 2 peripheral speed: 40 m / sec Feed speed: 10 m / min Depth of cut: 0.010mm / pass Workpiece material 4 (Material: SCM435, Hardness after heat treatment: HRC50)

[0083] The cutting performance (power consumption), surface roughness, and stability (rate of change in surface roughness from the initial to the final stage) during the above grinding operation were evaluated according to the criteria in Table 2. The evaluation results are shown in Table 3.

[0084] [Table 2]

[0085] [Table 3] [Industrial applicability]

[0086] The rotary dresser according to the present invention can be widely used in various manufacturing fields as a dressing means for general grinding wheels, CBN grinding wheels, and the like. [Explanation of symbols]

[0087] 10, 60 base money 10a, 20a, 30a, 60a, 70a, 80a outer surface 20, 21, 22, 70 abrasive grain layers 23, 27, 73 Abrasive grain section 23A, 73A diamond abrasive grains 23B, 73B Base area 24, 25A, 28A, 74 groove 25B, 28B subsulcus area 25, 28 grooves 30 backing layers 30b Rotation surface 50, 51, 52, 62 Dress section 60A protrusion 60B Cylindrical section 80 Protrusion 100, 101, 102, 200 Rotary Dresser

Claims

1. A rotary dresser comprising a dressing portion having a fixed portion on which an abrasive layer is provided, and the abrasive layer having an abrasive portion containing diamond abrasive grains fixed by plating and a groove portion containing grooves, The width of the groove is 1 / 4 or more of the average particle size of the diamond abrasive grains and 18 times or less of the average particle size of the diamond abrasive grains. The portion to be fixed is an annular backing layer that protrudes in a flange-like manner from the outer circumferential surface of a base metal having a disc-shaped portion. The abrasive layer is an annular abrasive layer formed on the rotating surface of the backing layer, A rotary dresser in which the grooves are formed to extend inward from the outer circumference of the abrasive layer.

2. A rotary dresser comprising a dressing portion having a fixed portion on which an abrasive layer is provided, and the abrasive layer having an abrasive portion containing diamond abrasive grains fixed by plating and a groove portion containing grooves, The width of the groove is 1 / 4 or more of the average particle size of the diamond abrasive grains and 18 times or less of the average particle size of the diamond abrasive grains. The fixed portion is a cylindrical projection that has the same axis as the base metal having a cylindrical portion and protrudes in one direction in the axial direction of the base metal. The abrasive layer is a cylindrical abrasive layer formed on the outer circumferential surface of the protrusion. A rotary dresser in which the groove is formed to extend from the working surface toward the base metal side.

3. The rotary dresser according to claim 1 or 2, wherein the total exposed area (projected area) of the diamond abrasive grains relative to the area of ​​the working surface of the abrasive grain layer excluding the groove portion is 7 area % or more and 71 area % or less.

4. In the usable portion, when the inter-grain distance between adjacent diamond abrasive grains is determined excluding the grooves in the outermost layer of the abrasive grain layer in the axial direction, 90% or more of the inter-grain distance is 2 / 3 times or more the average particle size of the diamond abrasive grains and 3 times or less the average particle size of the diamond abrasive grains. The rotary dresser according to claim 1 or 2, wherein, in the usable portion, when the intergrain distance between adjacent diamond abrasive grains is determined excluding the groove portion of the outermost layer in the normal direction of the abrasive grain layer, 90% or more of the intergrain distance is 2 / 3 times or more the average particle size of the diamond abrasive grains and 3 times or less the average particle size of the diamond abrasive grains.

5. The rotary dresser according to claim 1 or 2, wherein, in the abrasive layer, the theoretical number of diamond abrasive grains that can exist along the outer surface excluding the grooves is X, and the number of diamond abrasive grains existing along the outer surface excluding the grooves is N, such that 0.6 × X ≤ N ≤ X.

6. The grooves are provided on the outer circumference of the abrasive layer at intervals equal to or greater than the average particle size of the diamond abrasive grains, in the tangential direction. The rotary dresser according to claim 1 or 2, wherein the length of the groove in the direction perpendicular to the working surface of the abrasive grain layer is 0.7 times or more the length of the abrasive grain layer in the direction perpendicular to the working surface.

7. The average particle size of the diamond abrasive grains is 70 μm or more and 1000 μm or less. The rotary dresser according to claim 1 or 2, wherein the shape of the diamond abrasive grains is hexa-octahedral and / or truncated octahedral.

8. The portion to be fixed is 0.1 mm or more and 2.0 mm or less. The rotary dresser according to claim 1 or 2, wherein the outer diameter of the rotary dresser is 10 mm or more and 300 mm or less.

9. The groove has a pair of parallel sides and a bottom surface parallel to the rotating surface of the backing layer, The rotary dresser according to claim 1, wherein the groove is formed along a line connecting the outer circumference of the abrasive layer to the axis of the base metal, or is formed at an inclination with respect to the line connecting the outer circumference of the abrasive layer to the axis of the base metal.

10. The groove has a pair of parallel side surfaces and a bottom surface parallel to the outer circumferential surface of the protrusion. The rotary dresser according to claim 2, wherein the groove is formed to extend in a direction parallel to the axis or in a torsional direction.

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