JP5374035B2 - Vitrified superabrasive wheel manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a vitrified super abrasive grain grinding wheel capable of preventing the metal of a workpiece from being fused around a plurality of holes and the grinding quality such as ground surface accuracy from being degraded in a vitrified super abrasive grain grinding wheel formed by pasting vitrified stone pieces having super abrasive grains bound to each other with an inorganic binder and having a plurality of holes formed in the grinding surfaces thereof are stuck on the outer peripheral surface of a base. <P>SOLUTION: The plurality of holes 32 are dispersedly formed in the grinding surfaces 20 by emitting a laser beam L onto the grinding surfaces 20 of the vitrified stone pieces 26. Therefore, the plurality of holes 32 can be so formed in the grinding surfaces 20 that the binding structure of the vitrified stone pieces 26 is uniform, and hard portions to which super abrasive grains are prevented from being concentrated at the opening edge parts of the holes 32. Consequently, the fusing of the metal of the workpiece 104 does not occur around the holes 32, the grinding quality such as ground surface accuracy is not degraded, and stable grinding quality is provided when the workpiece 104 is ground. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing a vitrified superabrasive grinding wheel in which a plurality of vitrified grinding stone pieces to which superabrasive grains are bonded with an inorganic binder are bonded to the outer peripheral surface of a base metal.

  A vitrified superabrasive grindstone wheel in which a vitrified grindstone piece in which superabrasive grains such as CBN abrasive grains and diamond abrasive grains are bonded with a glassy inorganic binder is bonded to the outer peripheral surface of a base metal is known. Such a vitrified superabrasive wheel provides a relatively high grinding ratio and high grinding efficiency, for example, grinding a work material such as a steel material quenched by high-speed grinding with a peripheral speed of 120 m to 160 m / sec. In this case, it is preferably used.

  By the way, when the concentration of abrasive grains is increased in the vitrified grinding wheel piece, the wear is reduced, so there is an advantage that the durability life is extended and the running cost is lowered, but the amount of expensive superabrasive grains is increased and vitrified The superabrasive grinding wheel is expensive, and there is a drawback that grinding burn is likely to occur. On the other hand, if grinding is performed with a low concentration of abrasive grains, the occurrence of grinding burn can be avoided, but there is a drawback that wear is accelerated.

On the other hand, as shown in Patent Document 1, a vitrified superabrasive wheel using a vitrified grindstone piece in which a plurality of holes are dispersed and provided on the grinding surface of the vitrified grindstone piece has been proposed. According to this, since a plurality of holes are opened in the grinding surface, even if the concentration of superabrasive grains is increased, the coolant is sufficiently supplied, so that grinding burn is suitably performed while increasing the grinding efficiency. Reduced.
JP 2003-300165 A

  By the way, in the conventional vitrified superabrasive wheel, the vitrified grindstone piece used for the wheel is formed from a raw material mixed with superabrasive grains, vitrified bonds, a binder, and the like from a press mold, and the press molding thereof. A plurality of holes are formed at the same time as the press molding using a plurality of pins erected in a molding cavity of a press die used at the time. Then, the press-molded molded product is fired to obtain a vitrified grindstone piece.

  However, when a plurality of holes are formed by using the above press molding, abrasive grains and vitrified bond particles are easily concentrated around the pin in the process of applying the pressure of the press, and a plurality of holes are formed after firing. There was a problem in that the hard part where the superabrasive grains and the vitrified bond were densely formed was locally formed around the hole. The opening edge of the hole where the abrasive grains and vitrified bonds are concentrated is harder than the other parts in the connective structure of the vitrified stone pieces, making it difficult to wear out. In some cases, the grinding quality such as the accuracy of the grinding surface deteriorates.

  The present invention has been made against the background described above, and the object of the present invention is to provide a plurality of vitrified grindstone pieces in which superabrasive grains are bonded with an inorganic binder and a plurality of holes are provided on a grinding surface. Vitrified super-abrasive grinding wheel attached to the outer peripheral surface of the base metal does not cause metal welding of the work material around the hole, and vitrified ultra-compact that does not degrade grinding quality such as grinding surface accuracy It is providing the manufacturing method of an abrasive wheel.

  As a result of repeated studies on the background of the above circumstances, the present inventors have ground a plurality of holes in a state where the connective structure of the vitrified grindstone pieces is uniform when the vitrified grindstone pieces after firing are irradiated with laser light. It was found that it can be formed in a distributed manner on the surface, and stable grinding quality can be obtained for grinding of the work material. The present invention has been made based on this finding.

The invention according to claim 1 for achieving the above object is a super-abrasive disk-shaped base metal and an arc plate shape that is curved along an arc centering on the rotation axis of the base metal. A plurality of vitrified grindstone pieces having an abrasive layer bonded with an inorganic binder on the grinding surface side, and a plurality of vitrified grindstone pieces whose inner peripheral surface is bonded to the outer peripheral surface of the base metal A method of manufacturing a vitrified superabrasive grinding wheel according to claim 1, wherein a laser beam is irradiated to a ground surface of the vitrified grindstone piece after firing to penetrate each abrasive surface of the vitrified grindstone piece. A plurality of holes are provided in a distributed manner, and the plurality of holes are radially formed around the rotation axis in a plane perpendicular to the rotation axis of the base metal in each of the vitrified grindstone pieces. Features To.

  The invention according to claim 2 is the invention according to claim 1, wherein the plurality of holes have a diameter of 0.05 to 2.0 mmφ.

  The invention according to claim 3 is the invention according to claim 1 or 2, characterized in that the plurality of holes occupy 5 to 60% in area ratio on the grinding surface of the vitrified grindstone piece.

The invention according to claim 4 is the invention according to any one of claims 1 to 4, wherein the plurality of holes are equal in density except for a predetermined distance from an edge and a side edge of the vitrified grindstone piece. It is formed by these.

The invention according to claim 5 is the invention according to any one of claims 1 to 5, wherein the laser light is output from a YAG laser device.

According to vitrified method of manufacturing superabrasive grinding wheel of the invention according to claim 1, by irradiating a laser beam on the grinding surface of the vitrified abrasive piece after firing, the abrasive on the grinding surface of each of said vitrified abrasive piece since a plurality of holes through wood layer is provided each dispersion may connective tissue of vitrified grinding stone pieces form a plurality of holes in the ground surface in a uniform state, the opening edge of the hole super Since the occurrence of local hard parts with concentrated abrasive grains is eliminated, metal welding of the work material does not occur around the hole, and grinding quality such as grinding surface accuracy can be reduced. Therefore, stable grinding quality can be obtained for grinding of the work material. Further, since the plurality of holes are formed radially in the plane orthogonal to the rotation axis of the base metal in each of the vitrified grindstone pieces , the holes are supplied toward the grinding surface. The ground grinding liquid is taken into the plurality of holes and is preferably discharged toward the grinding point from the plurality of holes formed in the same direction as the centrifugal force.

  According to the method for manufacturing a vitrified superabrasive wheel of the invention according to claim 2, a vitrified grindstone piece having a plurality of holes having a diameter of 0.05 to 2.0 mmφ dispersed therein is obtained. Since it is a hole having a diameter preferable for grinding, which is difficult to obtain with a mold, suitable grinding quality can be obtained.

  According to the manufacturing method of the vitrified superabrasive wheel of the invention according to claim 3, since the plurality of holes occupy 5 to 60% in area ratio on the grinding surface of the vitrified grindstone piece, the concentration of superabrasive grains Even if the temperature is increased, the coolant is sufficiently supplied, so that grinding burn is prevented while increasing the grinding efficiency. In addition, since the chips are captured in the plurality of holes, the surface to be ground is not burned or cracked, and the quality of the surface to be ground is preferably improved.

  According to the manufacturing method of the vitrified superabrasive wheel of the invention according to claim 4, the plurality of holes are centered on the rotation axis in a plane orthogonal to the rotation axis of the vitrified superabrasive wheel. Therefore, the grinding fluid supplied toward the grinding surface is taken into the plurality of holes and is suitably discharged from the plurality of holes formed in the same direction as the centrifugal force toward the grinding point. The

According to the manufacturing method of the vitrified superabrasive wheel of the invention according to claim 4 , the plurality of holes are formed at an equal density except for a predetermined distance from the edge and side edge of the vitrified grindstone piece. Therefore, there is no decrease in mechanical strength at the edge and side edges of the vitrified grindstone piece, and cracks and the like are suitably prevented.

According to the method for manufacturing a vitrified superabrasive wheel of the invention according to claim 5 , since the laser beam is output from the YAG laser device, the wavelength thereof is 1.06 μm, so that the accuracy is high. A small-diameter hole can be formed.

  Preferably, the vitrified grindstone piece has a Knoop hardness of 3000 such as diamond abrasive grains, CBN abrasive grains, or mixed abrasive grains thereof with a concentration of greater than 10 and less than about 230, more preferably 20 to 200. The superabrasive grains of 60 mesh [average particle size 220 μm] to 800 mesh [average particle size 20 μm] are included. Moreover, Preferably it is provided with the porosity of 20-75 (volume%), More preferably, 30-65 (volume%). In addition, the vitrified grindstone piece may include a pore forming material such as an inorganic hollow material such as an inorganic balloon as an aggregate, if necessary.

Preferably, the inorganic binder is one suitable when superabrasive grains are used, such as borosilicate glass or crystallized glass. Moreover, as an inorganic binder for making the holding power of abrasive grains sufficient, α- (2 × 10 ⁻⁶ ) to α + (2 × 10 ⁻⁶ ) suitable for the thermal expansion coefficient α of superabrasive grains. Those having a thermal expansion coefficient in the range of [1 / K: room temperature to 500 ° C.] are selected.

  Preferably, the inorganic binder has a ratio of 15 to 35 (% by volume) with respect to the entire vitrified grindstone in order to maintain the holding power of the abrasive grains and to have the porosity as described above. Used.

In addition, a plurality of holes provided in the vitrified grindstone piece may be obtained in a desired size by adjusting the amount of the laser beam to be focused on the grinding surface at one point. Alternatively, a laser beam having a desired size may be obtained by performing a cutting process in which the ground surface is irradiated with laser light that has been narrowed to a predetermined narrowing amount and moved relative to the ground surface .

  The plurality of holes may be formed in all or a part of the plurality of vitrified grindstone pieces.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a front view showing a vitrified superabrasive wheel 10 manufactured by a manufacturing method according to an embodiment of the present invention. The vitrified superabrasive grinding wheel 10 has a disk shape made of metal such as carbon steel or aluminum alloy, and has a mounting hole 14 for mounting to a grinding device (for example, a cylindrical grinding machine 12 described later) at the center thereof. A base metal 18 provided with a portion 16, a circular arc plate shape curved along an arc centering on the rotation axis W of the base metal 18, and a grinding surface 20 corresponding to the outer peripheral surface thereof and the grinding surface 20 A plurality of (16 in this embodiment) vitrified grindstone pieces each having a bonding surface 22 corresponding to the inner peripheral surface on the opposite side, and the bonding surface 22 being bonded to the outer peripheral surface 24 of the base metal 18 without a gap. 26. The size is appropriately set depending on the application, but the vitrified superabrasive grinding wheel 10 of the present embodiment is configured, for example, with an outer diameter D of 380 mmφ and a thickness of about 10 mm excluding the mounting portion 16. is there.

  FIG. 2 is a perspective view showing the vitrified grindstone piece 26, and FIG. 3 is an enlarged view of a part of the cross section of the vitrified grindstone piece 26 in a plane orthogonal to the rotational axis W of the vitrified superabrasive grindstone wheel 10. FIG. 1 to 3, a vitrified grindstone piece 26 is an underlayer formed by bonding general abrasive grains of ceramic such as fused alumina, silicon carbide, or mullite with a vitreous inorganic binder (vitrified bond). 28 and an abrasive layer 30 in which superabrasive grains having a Knoop hardness of 3000 or more such as CBN abrasive grains and diamond abrasive grains are bonded with a glassy inorganic binder. The base layer 28 functions exclusively as a base for mechanically supporting the abrasive material layer 30, and the abrasive material layer 30 functions exclusively as a grindstone for grinding the work material. . As the superabrasive grains, those having a size in the range of 60 mesh [average particle size 250 μm] to 32000 mesh [average particle size 0.5 μm] are preferably used.

  As shown in FIG. 2, a plurality (36 in the present embodiment) of the same size holes 32 are uniformly distributed in the grinding surface 20, that is, distributed on the grinding surface 20 of the vitrified grinding wheel piece 26. For example, the vitrified grindstone pieces 26 are formed at an equal density excluding a predetermined distance K from the end and side edges. The plurality of holes 32 have, for example, a diameter of 0.05 to 2.0 mmφ, and occupy, for example, 5 to 60% in the area ratio on the grinding surface 20. Further, in FIG. 3, that is, in the plane orthogonal to the rotational axis W of the vitrified superabrasive grinding wheel 10, the plurality of holes 32 are formed radially with the rotational axis W as the center. It penetrates the layer 30. That is, the plurality of holes 32 are formed in the radial direction of the vitrified superabrasive grinding wheel 10 and have a center line passing through the rotation axis W.

  The plurality of holes 32 are provided by irradiating the grinding surface 20 of the vitrified grindstone piece 26 with the laser light L output from the YAG laser device 34, and FIG. 4 includes the YAG laser device 34. It is the side view which notched and showed the principal part of the laser processing machine 36 which implements the said drilling. 5 is a cross-sectional view taken along line VV in FIG.

  4 and 5, the base 38 includes a leg portion 40 made of a metal frame such as SS400, and a rectangular plate base 42 made of a metal plate such as SS400 provided horizontally on the upper surface thereof. . A column 44 having a rectangular cross section is erected on the square of the upper surface of the base 62, and a top plate 46 having a through hole 45 in the thickness direction of the central portion is fixed horizontally on the upper surface of the column 44. Has been. Also, on the upper surface of the base 42, a side surface 52 in which a pair of rectangular plate-like first support plate 48 and second support plate 50 having a longitudinal direction in the thickness direction of the base 42, that is, the vertical direction in FIG. , 54 are erected. In the first support plate 48 and the second support plate 50, a cylindrical swinging rotary shaft 60 rotates around its axis W1 through a pair of bearings 58 fitted in a pair of through holes 56 thereabove. It is horizontally provided in a state where it is supported.

  The swinging rotary shaft 60 is provided with a key 62 having a rectangular cross section having a longitudinal direction in a direction parallel to the axis W1 on the outer periphery of the central portion in the longitudinal direction. At the center in the longitudinal direction of the oscillating rotary shaft 60 is a cylindrical shape having a hole shape slightly larger than the cross-sectional shape of the oscillating rotary shaft 60 including the key 62, and recessed in a circumferential direction at a predetermined position on the outer periphery. A slide member 66 in which a groove 64 is formed is fitted. With the above configuration, the slide member 66 is slidable in the direction of the axis W1 with respect to the swing rotation shaft 60, and is not rotatable relative to the axis W1. A ring-shaped rotary sliding member 68 is fitted on the outer periphery of the slide member 66 so as to be rotatable relative to the slide member 66 around the axis W1. Are provided with a plate-like first sandwiching plate 70 and a second sandwiching plate 72 respectively protruding upward. The first sandwiching plate 70 and the second sandwiching plate 72 have a V-shape that is relatively rotated by a predetermined angle with the shaft center W1 as an intersection in the direction of the shaft center W1, and projecting from surfaces facing each other. The tension springs 76 having both ends fixed to a pair of ring-shaped rings 74 are biased toward each other. Further, the first sandwiching plate 70 and the second sandwiching plate 72 are each provided with a notch 78 at the tip of the opposing surface. The notch 78 is used for positioning and placing the workpiece, that is, the vitrified grindstone piece 26, and the vitrified grindstone piece 26 is separated from the first clamping plate 70 and the first holding plate 70 which are separated from the urging force of the tension spring 76. Both ends are placed in the notch 78 of the second sandwiching plate 72, and then the separation is released, so that the first sandwiching plate 70 and the second sandwiching plate 72 are sandwiched. Here, the distance R from the axis W1 to the grinding surface 20 of the vitrified grindstone piece 26 sandwiched is set to be the same distance as the radius D / 2 of the vitrified superabrasive wheel 10. In the present embodiment, the slide member 66, the rotary sliding member 68, the first clamping plate 70, the second clamping plate 72, and the tension spring 76 constitute a fixture for the vitrified grindstone piece 26.

  In FIG. 4, a pulse motor 82 having an output shaft having an axis parallel to the axis W1 is provided on the side surface 52 of the first support plate 48. A small gear 84 is provided at the tip of the output shaft. It is fixed. The small gear 84 is engaged with a first gear 86 provided so as to be rotatable about an axis in a direction parallel to the axis W 1, and the first gear 86 is fixed to the swinging rotation shaft 76. The second gear 88 is engaged. For this reason, the vitrified grindstone piece 26 is operated by the pulse motor 82 and the output shaft thereof is rotated by a predetermined amount, and the swinging rotary shaft 76 is moved through the small gear 84, the first gear 86, and the second gear 88. As a result of being rotated by an amount corresponding to a predetermined amount, positioning is performed around the axis W1.

  A pulse motor 92 including a screw shaft 90 having an axis parallel to the axis W1 as an output shaft is provided on the side surface 54 of the second support plate 50. The screw shaft 90 has a nut portion 94 screwed to the screw shaft 90, and a tip that is bifurcated from the nut portion 94 and protrudes upward is engaged with the concave groove 64 of the slide member 66. A fork 98 having a U-shaped fork portion 96 is provided. For this reason, the vitrified grindstone piece 26 is moved through the fork 98 by operating the pulse motor 92 and rotating the screw shaft 90 as an output shaft by a predetermined angle to move the fork 98 in the direction of the axis W1. As the slide member 80 is moved in the direction of the axis W1, the slide member 80 is positioned in the direction of W1.

  On the top surface of the top plate 46, for example, a YAG laser device 34 having an average output of 120 W is placed and fixed. This YAG laser device 34 is a pulsed laser oscillated and adjusted by the laser oscillation unit 100 at, for example, a wavelength of 1.06 μm, a pulse width of 0.3 to 5.0 ms, a peak output of 20 kW, energy of 50 J, and a pulse frequency of 500 Hz or less. The light L is emitted from the tip of the laser head 102 via the laser head 102 provided on the side surface of the laser oscillation unit 100 and having the tip directed toward the axis W1 of the swinging rotation shaft 76.

  FIG. 6 is a process diagram illustrating the main part of the method for manufacturing the vitrified superabrasive grinding wheel 10. In FIG. 6, first, in the raw material blending step P <b> 1, abrasive grains that are raw materials for the vitrified grinding stone pieces 26, a vitreous inorganic binder (vitrified bond), and a certain amount of mutual caking force at the time of molding are generated. Weigh out a binder (amount of glue) such as dextrin and a pore forming agent such as an organic substance or an inorganic balloon, which are mixed as necessary, at a ratio set in advance for each of the abrasive layer 30 and the base layer 28. And mix each. Note that the pore forming agent is not necessarily used. In this embodiment, for example, the ratio shown in Table 1 below for the abrasive layer 30 and the ratio shown in Table 2 below for the underlayer 28 are used. Use raw materials.

[Table 1]
Raw material name Ratio ――――――――――――――――――――
CBN abrasive grains (# 80/100) 50 capacity parts Vitrified bond 20 capacity parts Glue amount 6 capacity parts

[Table 2]
Raw material name Ratio ――――――――――――――――――――
Spherical mullite 35 capacity parts Electromelted mullite 14 capacity parts Vitrified bond 20 capacity parts Glue amount 6 capacity parts

  Next, in the molding step P2, the raw material for the abrasive layer 30 and the raw material for the base layer 28 mixed in the molding cavity of a predetermined molding die are sequentially filled and pressurized, as shown in FIG. A shaped molded body is formed. Next, in the firing step P3, the molded body is fired at, for example, a temperature of 1000 ° C. or less for 5 hours, thereby producing a vitrified grindstone piece 26 having a length of 40 mm, a width of 10.4 mm, and a thickness of 7.4 mm, for example. . By the firing, organic substances such as a binder contained in the raw material are disappeared and the inorganic binder is melted, and then the abrasive grains are bonded to each other by the hardened inorganic binder. As a result, a porous vitrified grindstone structure having a large number of continuous pores in which superabrasive grains are bound by the inorganic binder is formed on the produced vitrified grindstone piece 26.

  Next, in the drilling step P4, the laser beam L output from the YAG laser device 34 is applied to the grinding surface 20 of the vitrified grindstone piece 26 placed and positioned on the laser processing machine 36 shown in FIGS. Thus, a plurality of holes 32 having a diameter of, for example, 0.5 mmφ are provided in a distributed manner on the grinding surface 20 of the vitrified grindstone piece 26. The plurality of holes 32 are formed at an equal density excluding the range of a predetermined distance K from the end edge and side edge of the vitrified grindstone piece 80, and are formed so as to occupy 5 to 60% in area ratio on the grinding surface 20. . The plurality of holes 32 are formed so as to penetrate the base layer 28 and the abrasive layer 30 in a radial manner centering on a predetermined position in a plane orthogonal to the width direction of the vitrified grindstone piece 26.

  Next, in the attaching step P5, the vitrified grindstone piece 26 provided with the plurality of holes 32 is attached to the outer peripheral surface 24 of the base 18 prepared in advance using, for example, an epoxy resin adhesive without any gaps. Next, in the finishing step P6, the surface of the base metal 18 to which the vitrified grindstone piece 26 is attached, that is, the surface of the vitrified superabrasive grindstone wheel 10 is applied to a predetermined depth, for example, about 0.5 to 1 mm using a dressing tool or a cutting tool. The outer diameter dimension D of the vitrified superabrasive grinding wheel 10, the roundness of the outer diameter dimension D, the thickness dimension, and the like are adjusted. The vitrified grindstone piece 26 is produced so as to have a predetermined size that is larger by the above-described cutting allowance when the firing step P3 is completed. Through the above steps, a vitrified superabrasive grindstone wheel in which a vitrified grindstone piece 26 in which superabrasive grains are bound by an inorganic binder is bonded to the outer peripheral surface 24 of the base metal 18 as shown in FIG. 10 is manufactured.

  FIG. 7 is a diagram showing an example of a usage state of the manufactured vitrified superabrasive wheel 10, and a work material (camshaft) is processed by a cylindrical grinder 12 to which the vitrified superabrasive wheel 10 is mounted. ) 104 is a side view showing a state in which the main part 104 is being ground with the main part cut away. In FIG. 7, a cylindrical grinding machine 12 is perpendicular to the paper surface with a work material 104 sandwiched between a bed 106 as a base and a tailstock shaft of a tailstock (not shown) provided on the bed 106. A headstock 108 having a main shaft that rotates around a central axis W2 and a servomotor 110 that can move in a direction parallel to the axis W2 along a pair of rails 112 and a servomotor 114 along a pair of rails 116. A table 120 movable in a direction Y perpendicular to the axis W2, and a motor 122 provided on the table 120 and rotated around an axis W3 perpendicular to the paper surface via a pulley 124, a belt 126, and a pulley 128. A grinding wheel base 132 having a rotating main shaft 130 and a coolant (also called grinding fluid) supplied by a pump (not shown) are injected at a predetermined pressure. A pair of nozzles 134, 136 are provided with. The vitrified superabrasive grindstone wheel 10 is attached to the rotation main shaft 130 in a state where the rotation axis W of the vitrified superabrasive wheel 10 coincides with the axis W3. The grinding by the cylindrical grinder 12 is performed by supplying coolant to the grinding point P between the vitrified superabrasive grinding wheel 10 rotating from one nozzle 134 and the work material 104 and from the other nozzle 136. The grinding surface of the rotating vitrified superabrasive grinding wheel 10 is rotated by moving the grinding wheel base 132 in the direction Y toward the workpiece 104 while the coolant is sprayed onto the grinding surface 20 of the vitrified superabrasive grinding wheel 10. The workpiece 104 is ground by 20. At this time, the coolant is sprayed onto the vitrified superabrasive wheel 10 by the nozzle 136 at a position away from the grinding point P in the direction opposite to the rotational direction R of the vitrified superabrasive wheel 10, thereby cleaning the grinding surface 20. The coolant is supplied into the plurality of holes 32 while the chips in the plurality of holes 32 are discharged.

  As described above, according to the method for manufacturing the vitrified superabrasive wheel 10 of the present embodiment, the grinding surface 20 of the vitrified grindstone piece 26 is irradiated by irradiating the grinding surface 20 of the vitrified grindstone piece 26 with the laser beam L. Since the plurality of holes 32 are provided in a distributed manner, the plurality of holes 32 can be formed in the ground surface 20 with the connective structure of the vitrified grinding stone pieces 26 being uniform, and super Since the occurrence of local hard parts with concentrated abrasive grains is eliminated, metal welding of the work material (camshaft) 104 does not occur around the hole 32 and grinding such as grinding surface accuracy is possible. Stable grinding quality can be obtained for grinding of the work material 104 without degrading the quality.

  Moreover, according to the manufacturing method of the vitrified superabrasive grinding wheel 10 of the present embodiment, the vitrified grindstone pieces 26 having a plurality of holes 32 having a diameter of 0.05 to 2.0 mmφ are obtained. Since the hole 32 has a diameter preferable for grinding, which is difficult to obtain with a press mold, suitable grinding quality can be obtained.

  Moreover, according to the manufacturing method of the vitrified superabrasive wheel 10 of the present embodiment, the plurality of holes 32 occupy 5 to 60% in area ratio in the grinding surface 20 of the vitrified grindstone piece 26. Even if the degree of concentration is increased, the coolant is sufficiently supplied, so that grinding burn can be prevented while increasing the grinding efficiency. In addition, since the chips are captured in the plurality of holes 32, the surface to be ground is not burned or cracked, and the quality of the surface to be ground is preferably improved.

  Moreover, according to the manufacturing method of the vitrified superabrasive grinding wheel 10 of the present embodiment, the plurality of holes 32 have their rotational axes W in the plane orthogonal to the rotational axis W of the vitrified superabrasive grinding wheel 10. Since the center is formed radially, coolant (grinding fluid) supplied toward the grinding surface 20 is taken into the plurality of holes 32 and from the plurality of holes 32 formed in the same direction as the centrifugal force. It is preferably discharged towards the grinding point P.

  Moreover, according to the manufacturing method of the vitrified superabrasive grinding wheel 10 of the present embodiment, the plurality of holes 32 are formed at an equal density except for a predetermined distance from the edge and side edge of the vitrified grinding wheel piece 26. Therefore, there is no decrease in mechanical strength at the edge and side edges of the vitrified grindstone piece 26, and cracking and the like are suitably prevented.

  Moreover, according to the manufacturing method of the vitrified superabrasive grinding wheel 10 of the present embodiment, since the laser light L is output from the YAG laser device 34, the wavelength thereof is 1.06 μm. The small-diameter hole 32 can be formed well.

  As mentioned above, although one Example of this invention was described in detail with reference to drawings, this invention is not limited to this Example, It can implement in another aspect.

  For example, in the above-described embodiment, the cross-sectional shape of the plurality of holes 32 is circular. However, the shape is not limited to this, and may be an elliptical shape, a polygonal shape such as a rectangle or a triangle, and a long hole shape. The plurality of holes 32 may have different cross-sectional shapes instead of the same cross-sectional shape.

  Further, in the above-described embodiment, the plurality of holes 32 are formed radially around the rotation axis W of the vitrified superabrasive grinding wheel 10 and penetrate the base layer 28 and the abrasive layer 30, but are not necessarily limited. It does not have to be radial about the rotation axis W. Moreover, it is not always necessary to penetrate the vitrified grinding stone piece. In short, it is only necessary that a plurality of holes are opened in the grinding surface.

  Further, in the above-described embodiment, the plurality of holes 32 are formed at an equal density except for a predetermined distance from the end edge and side edge of the vitrified grindstone piece 26, but are not necessarily equal density. What is necessary is just to be distributed and provided.

  In the above-described embodiment, the laser beam output from the YAG laser device is used. However, the laser beam output from other laser devices may be used.

  Further, in the above-described embodiment, the base metal 18 is made of a metal such as carbon steel, an aluminum alloy and the like, and this configuration is preferable in order to have a strength that can withstand high-speed rotation, but is not limited thereto. It may be made of a fiber reinforced resin or a vitrified grindstone.

  Further, in the above-described embodiment, the configuration for positioning the vitrified grindstone material piece 80 of the laser processing machine 36 is disclosed as an example, and can be realized by other mechanical configurations.

  It should be noted that the above description is merely an embodiment, and other examples are not illustrated. However, the present invention is implemented in variously modified and improved modes based on the knowledge of those skilled in the art without departing from the gist of the present invention. Can do.

It is a front view which shows the vitrified superabrasive wheel manufactured by the manufacturing method of a present Example. It is the perspective view which showed the vitrified grindstone piece of FIG. It is the figure which expanded and showed a part of cross section of the vitrified grindstone piece in the surface orthogonal to the rotating shaft center of the vitrified superabrasive wheel of FIG. It is the side view which notched and showed the principal part of the laser processing machine provided with a YAG laser apparatus and drilling a vitrified grindstone piece. FIG. 5 is a VV sectional view of FIG. 4. It is process drawing explaining the principal part of the manufacturing method of a vitrified superabrasive grindstone wheel. It is a figure which shows an example of the use condition of the vitrified superabrasive wheel of FIG. 1, Comprising: The state which grinds a work material (camshaft) with the cylindrical grinding machine with which the vitrified superabrasive wheel is equipped is required. It is the side view which notched and showed the part.

Explanation of symbols

10: Vitrified superabrasive wheel 18: Base metal 20: Grinding surface 24: Outer peripheral surface 26: Vitrified grinding wheel piece 32: Hole 34: YAG laser device 104: Work material (camshaft)
L: Laser beam P4: Drilling step W: Rotation axis

Claims (5)

A disc-shaped base metal and an arc plate shape curved along an arc whose center of curvature is the center of rotation of the base metal, and the abrasive layer to which superabrasive grains are bonded by an inorganic binder is ground. A plurality of vitrified grindstone pieces on the side, and a vitrified superabrasive grindstone wheel manufacturing method in which an inner peripheral surface of the vitrified grindstone piece is attached to an outer peripheral surface of the base metal,
By irradiating the grinding surface of the vitrified grindstone piece after firing with laser light, a plurality of holes penetrating the abrasive layer are provided on each grinding surface of the vitrified grindstone piece, respectively ,
In the vitrified superabrasive grinding wheel, the plurality of holes are formed radially in the plane orthogonal to the rotation axis of the base metal in each of the vitrified grinding wheel pieces . Production method.   The method for manufacturing a vitrified superabrasive wheel according to claim 1, wherein the plurality of holes have a diameter of 0.05 to 2.0 mmφ.   3. The method of manufacturing a vitrified superabrasive wheel according to claim 1, wherein the plurality of holes occupy 5 to 60% in terms of area ratio on the grinding surface of the vitrified grindstone piece.   4. The vitrified superabrasive grindstone according to claim 1, wherein the plurality of holes are formed at an equal density excluding a predetermined distance from an end edge and a side edge of the vitrified grindstone piece. 5. Wheel manufacturing method.   The method of manufacturing a vitrified superabrasive wheel according to any one of claims 1 to 4, wherein the laser beam is output from a YAG laser device.

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