JP2006136957A - Grinding wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grinding wheel to hardly generate clogging of an abrasive grain part. <P>SOLUTION: The abrasive grain part 14 fixed with abrasive grain is formed at an outer edge of base metal 12 made of cup type stainless steel. The radial direction width of the base metal 12 in the abrasive grain part 14 is 10 to 20mm which is wider than a conventional width. In the abrasive grain part 14, a plurality of radially extending slits 16 are formed. The slits 16 are provided so that the number of the slits 16 may be 0.16≤the number of the slits/outer diameter(mm) of the abrasive grain part≤0.24. Each of the slits 16 is formed so that a center line of the longitudinal direction may form an angle of 45°to 60° with the radial direction of the grinding wheel (base metal 12). The plurality of slits 16 are formed into shape to eddy counterclockwise. By this constitution, the grinding wheel 10 is made hard to generate clogging of the abrasive grain part 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a grinding wheel.

Conventionally, in grinding processing of a cylinder block or the like, a grinding wheel is used in which abrasive grains such as diamond are fixed to the outer edge portion of a disk-shaped base metal. In such a grinding wheel, by providing a slit in an abrasive grain portion to which abrasive grains are fixed, the grinding fluid and shaving powder are discharged through the slit.
JP-A-6-179166

  In such a grinding wheel, for example, in the case of a grinding wheel having a diameter of 250 mm, one provided with 30 slits is the mainstream. However, such a grinding wheel has a problem in that the abrasive grains are easily clogged and the overhead due to maintenance increases.

  In view of such circumstances, the present invention intends to provide a grinding wheel in which clogging of an abrasive grain portion is unlikely to occur.

  The present invention is a grinding wheel having an abrasive grain portion in which abrasive grains are fixed to the outer edge of a disk-shaped base metal, wherein the abrasive grain portion is provided with slits, and the number of slits is 0.16 ≦ the number of slits / The outer diameter (mm) of the abrasive grain portion is 0.24, and the angle between the longitudinal center line of the slit and the radial direction of the base metal is 45 ° to 60 °.

  Thus, the number of slits provided in the abrasive grain portion is 0.16 ≦ the number of slits / the outer diameter of the abrasive grain portion (mm) ≦ 0.24, and the center line in the longitudinal direction of the slit is the radial direction of the base metal Since the angle formed is 45 ° to 60 °, the removal of the shaving powder and the grinding liquid proceeds smoothly and clogging is less likely to occur. The “center line in the longitudinal direction” means a line connecting the midpoints of both ends of the slit when the width of the slit differs depending on the longitudinal direction of the slit.

  In this case, it is preferable that the width of the abrasive grain portion in the radial direction is 10 to 20 mm. In this configuration, since the width of the abrasive grain portion in the radial direction is as wide as 10 to 20 mm, a large margin can be taken, a deep cut and a high feed rate can be realized, and processing can be performed with high efficiency.

  In this case, in the abrasive grain portion, the boundary line between the portion where the slit is provided and the portion where the slit is not provided can be parallel across the portion where the slit is provided. According to this structure, since it becomes a slit with a parallel boundary line, when manufacturing a grinding wheel, it is easy to perform the process which provides a slit, after fixing an abrasive grain to a base metal. Further, when the workpiece is ground, clogging is less likely to occur.

  Alternatively, in the abrasive grain portion, the boundary line between the portion where the slit is provided and the portion where the slit is not provided can be parallel across the portion where the slit is not provided. According to this configuration, since the boundary line of the part where the abrasive grains are fixed is parallel, when the grinding wheel is manufactured, the chip to which the abrasive grains are fixed is bonded to form the abrasive part. easy. Further, as a result, the slit becomes a shape opened to the outside of the grinding wheel, so that when the grinding liquid is discharged from the inside to the outside of the wheel, clogging is difficult and the discharge efficiency is improved.

  According to the grinding wheel of the present invention, it is possible to obtain a grinding wheel in which clogging of the abrasive grains is less likely to occur, reducing overhead due to maintenance, and improving grinding efficiency.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing a grinding wheel according to an embodiment of the present invention. The grinding wheel 10 of this embodiment is configured as a single layer abrasive cup type grinding wheel. An abrasive grain portion 14 to which abrasive grains are fixed is formed on the outer edge of a base metal 12 made of cup-type stainless steel as shown in FIG. Examples of the abrasive grains used in the abrasive grain portion 14 include natural diamond, synthetic diamond, and CBN.

  The width of the abrasive grain portion 14 in the radial direction is 10 to 20 mm, which is wider than the conventional width of about 5 mm. Thus, since the width of the abrasive grain portion 14 is wide, deep cutting can be realized when grinding an object to be ground, and roughing and finishing can be performed simultaneously.

  A plurality of slits 16 extending radially are formed in the abrasive grain portion 14. The slits 16 are provided so that the number of slits is 0.16 ≦ the number of slits / the outer diameter (mm) of the abrasive grain portion ≦ 0.24. For example, when the outer diameter of the abrasive part is 250 mm, the number of slits is 40 to 60. More preferably, the slit 16 is 0.19 ≦ the number of slits / the outer diameter of the abrasive part (mm) ≦ 0.20 (when the outer diameter of the abrasive part is 250 mm, the number of slits is 48 to 50). Is formed. The width of the slit is 13 to 17 mm.

  FIG. 2 is a diagram showing an abrasive grain part of the grinding wheel according to the embodiment of the present invention. As shown in FIG. 2, the slit 16 is formed such that the center line in the longitudinal direction forms an angle of 45 ° to 60 ° with the radial direction of the grinding wheel 10 (base metal). 16 has a shape that spirals counterclockwise. In this case, as shown in FIG. 3, it can also be set as the shape where the some slit 16 spirals clockwise. The direction in which the angle of the slit is given can be appropriately changed depending on the direction of discharging the grinding fluid and the direction of rotation of the grinding wheel. This will be described later.

  FIG. 4 is an enlarged view showing the vicinity of the slit of the grinding wheel according to the embodiment of the present invention. In the abrasive grain portion 14 of the present embodiment, the boundary lines l and l ′ between the portion where the slit 16 is provided and the portion where the slit 16 is not provided are parallel to each other across the portion where the slit is provided. It has become. For this reason, the slit 16 becomes a slit in which the boundary line extends in parallel, so that the grinding liquid can be easily discharged from both the outer peripheral direction and the inner peripheral direction of the abrasive grain portion 14. Moreover, in grinding wheel manufacture, when the slit 16 is formed after the abrasive grains are fixed to the abrasive grain portion 14, the process of forming the slit 16 is facilitated.

  On the other hand, as shown in FIG. 5, in the abrasive grain portion 14, boundary lines l and l ′ between a portion where the slit 16 is provided and a portion where the slit 16 is not provided are portions where the slit 16 is not provided. It can also be made parallel by being sandwiched. In this case, in the abrasive grain part 14, the boundary line of the part to which the abrasive grain was fixed becomes parallel. Since the slit 16 has a shape opened toward the outer periphery of the grinding wheel 10, when the grinding liquid is ejected from the inner peripheral side of the grinding wheel and discharged to the outer peripheral side of the grinding wheel, the grinding liquid is discharged. Efficiency is improved.

  Various forms of forming such an abrasive grain part are conceivable. FIGS. 6A to 6E are views showing the structure of the abrasive grains of the grinding wheel according to the embodiment of the present invention. In FIG. 6A, after the abrasive grains 18 are placed on portions other than the slits 16 of the abrasive grain portion 14, powdery silver-based or tin-based brazing material is sprayed on the entire surface of the abrasive grain portion 14, and thereafter A mode in which the abrasive grains 18 are fixed by sintering is shown. In this embodiment, the portion where the abrasive grains 18 are not fixed becomes the slit 16 as it is, and there is an advantage that the manufacturing process is simple.

  FIG. 6B shows a mode in which a groove serving as a slit 16 is provided in the base metal 12 in advance, and abrasive grains 18 are fixed to a portion other than the groove with a brazing material. Since the groove is provided first, the manufacturer can easily recognize the portion to which the abrasive grains 18 are to be fixed, and the manufacturing is easy. In this case, the abrasive grain portion 14 as shown in the figure may be formed by fixing the abrasive grain 18 to the entire surface of the abrasive grain portion 14 and then grinding the portion that becomes the slit 16. Even with this method, the abrasive grains 14 can be easily formed.

  FIG. 6C shows a mode in which the base metal 12 is not provided with a groove or the like that becomes the slit 16, and the abrasive grains 18 are fixed to portions other than the slit 16. In this aspect, there is an advantage that processing such as grinding a groove for forming the slit 16 becomes unnecessary.

  FIG. 6D shows a mode in which grooves are provided in places other than the slits 16 of the base metal 12 and the abrasive grains 18 are fixed to the grooves, contrary to FIG. 6B. In this aspect, there is an advantage that the part where the abrasive grains 18 are to be fixed is easily understood by the manufacturer and that the manufacture is easy.

  FIG. 6E shows a state in which a chip 22 having abrasive grains 18 fixed in advance by a brazing material 20 is prepared in advance and the chip 22 is bonded to a portion other than the slit 16 of the abrasive grain portion 14 by an adhesive layer 24. Show. This embodiment is characterized by being suitable for mass production because it uses a chip to which abrasive grains are fixed in advance.

  In addition to the above, the abrasive grains can be fixed by means such as adhesion and electrodeposition.

  The operation of the grinding wheel as described above will be described below. In a conventional grinding wheel, for example, only about 30 slits are provided in a grinding wheel having a diameter of 250 mm. However, with this number of slits, the slits are easily clogged. Therefore, in this embodiment, the number of slits is increased from the conventional one. Clogging started to decrease from 36 or more (0.144 ≦ number of slits / outer diameter of abrasive part (mm)) with a grinding wheel having a diameter of 250 mm, and 40 or more (0.16 ≦ number of slits / of abrasive part). By setting the outer diameter (mm), clogging can be substantially prevented. Here, if too many slits are provided, the portion where the abrasive grains are fixed in the abrasive grain portion becomes too small and the grinding efficiency deteriorates. Therefore, the number of slits is 60 or less with a grinding wheel having a diameter of 250 mm (the number of slits / abrasive grains). It is preferable that the outer diameter of the part (mm) ≦ 0.24). From the above, 40 to 60 grinding wheels with a diameter of 250 mm (0.16 ≦ number of slits / outer diameter of abrasive part (mm) ≦ 0.24), more preferably 48 to 50 (0.19 ≦ number of slits). / Clogging can be prevented by setting the outer diameter of the abrasive part (mm) ≦ 0.20. In addition, when the number of abrasive grains per unit area is constant, an increase in the number of slits reduces the area of all abrasive grains, thereby reducing the grinding resistance and improving the machining accuracy.

  Moreover, when providing a slit, it is preferable to provide with an angle with respect to the radial direction of a grinding wheel. If a slit is provided without making an angle with respect to the radial direction of the grinding wheel, the cutting powder ground on the outer periphery of the grinding wheel can only be caught by the slit at the end of the slit, making it difficult for the cutting powder to fall into the slit, This is because the shavings are not easily discharged. However, if the angle formed by the slit and the radial direction of the grinding wheel is too large, the length of the slit becomes longer, and the distance until the cutting powder caught by the slit is discharged becomes longer, and the cutting powder is discharged instead. Efficiency is reduced. Therefore, in the present embodiment, the cutting powder can be efficiently discharged by setting the angle formed by the center line in the longitudinal direction of the slit and the radial direction of the base metal to be 45 ° to 60 °.

  FIG. 7 is a view for explaining the action of discharging the grinding fluid and the shaving powder of the grinding wheel according to the embodiment of the present invention. In this aspect, the grinding wheel 10 is rotated counterclockwise, and the grinding liquid is ejected from the inner peripheral side of the grinding wheel 10 and discharged to the outer peripheral side of the grinding wheel 10. In this case, the slit is provided with an angle that vortexes counterclockwise as shown in FIG. 2 so that the grinding liquid and the cutting powder are easily discharged along the rotation direction of the grinding wheel 10 and the flow of the grinding liquid. Formed.

  On the other hand, as shown in FIG. 8, when the grinding wheel 10 is rotated counterclockwise and the grinding liquid is ejected from the outer peripheral side of the grinding wheel 10 and discharged to the inner peripheral side of the grinding wheel 10, the grinding wheel 10 The slits are formed at an angle that vortexes clockwise as shown in FIG. 3 so that the grinding fluid and the cutting powder can be easily discharged along the rotation direction and the flow of the grinding fluid.

  FIGS. 9A and 9B are views showing the relationship between the abrasive grain width of the grinding wheel and the set allowance. In the grinding wheel, it is preferable to achieve deep cutting and perform roughing and finishing simultaneously. Moreover, it is preferable to shorten the processing time of the material to be ground as a high feed rate. To achieve a deep cut, a large margin is required. As shown in FIGS. 9A and 9B, the taper angle θ ′ is usually provided in the abrasive grain portion 14 in order to increase the margin. The taper angle θ ′ is usually around 5 ° to 15 °. As shown in FIGS. 9 (a) and 9 (b), when the taper angle θ ′ is provided and the allowance is increased, if the allowance x <the allowance y is satisfied, the abrasive grain width X < It becomes the abrasive grain width Y and the abrasive grain width becomes large. However, in the conventional grinding wheel, if the abrasive grain width is increased beyond 5 mm, clogging is likely to occur, so that the allowance has to be reduced. Moreover, clogging was easy to occur even at a high feed rate. Therefore, conventionally, it has been difficult to achieve high efficiency (deep cutting, high feed rate). On the other hand, in this embodiment, since the abrasive grain part 14 is hard to cause clogging, the abrasive grain width can be increased to 10 to 20 mm to realize deep cutting. In addition, since the clogging hardly occurs even at a high feed rate, the processing time can be shortened. Furthermore, when the number of abrasive grains per unit area is constant, the number of abrasive grains increases as the abrasive grain width increases, resulting in a long life.

Experimental example 1
Hereinafter, the result of conducting an experiment of grinding an object to be ground using a grinding wheel is shown. A plurality of grinding wheels having synthetic diamond abrasive grains fixed to the outer edge of a base metal made of stainless steel (SUS304) having an outer diameter of 260 mm were prepared. In each grinding wheel, slits were formed such that the number of slits was 38 to 48, and the angle between the longitudinal center line of the slit and the radial direction of the base metal was 0 ° to 60 °. The material to be ground was ground with these grinding wheels. The grinding test conditions are as follows.

Test conditions:
Machine used Mori Seiki Co., Ltd. Machining center table speed (feed speed) 2000mm / min
Wheel rotation speed 4000rpm
Cutting depth 1mm
Material to be ground Aluminum alloy AC4B-T6

  FIG. 10 is a diagram showing the experimental results of this experimental example. As shown in FIG. 10, the number of slits is 0.18 ≦ the number of slits / the outer diameter (mm) of the abrasive grains ≦ 0.24 (the outer diameter is 260 mm and the number of slits is 47 to 62), and the slit is a base metal. The angle formed with the radial direction of No. is 45 ° to 60 °. As for 3, 4, 5, 8, and 9, it can be seen that there is no clogging and the surface finish is good.

  In addition, the grinding wheel of this invention is not limited to above-described embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention.

It is a perspective view which shows the grinding wheel which concerns on embodiment of this invention. It is a figure which shows the abrasive grain part of the grinding wheel which concerns on embodiment of this invention. It is a figure which shows the abrasive grain part of the grinding wheel which concerns on embodiment of this invention. It is an enlarged view which shows the slit vicinity of the grinding wheel which concerns on embodiment of this invention. It is an enlarged view which shows the slit vicinity of the grinding wheel which concerns on embodiment of this invention. (A)-(e) is a figure which shows the structure of the abrasive grain part of the grinding wheel which concerns on embodiment of this invention. It is a figure explaining the effect | action which discharges the grinding fluid of the grinding wheel which concerns on embodiment of this invention, and cutting powder. It is a figure explaining the effect | action which discharges the grinding fluid of the grinding wheel which concerns on embodiment of this invention, and cutting powder. (A) (b) is a figure which shows the relationship between the abrasive grain part width | variety of a grinding wheel, and a setting allowance. It is a figure which shows the experimental result of this experimental example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Grinding wheel, 12 ... Base metal, 14 ... Abrasive grain part, 16 ... Slit, 18 ... Abrasive grain, 20 ... Brazing material, 22 ... Chip, 24 ... Adhesive layer

Claims (4)

  A grinding wheel having an abrasive grain portion in which abrasive grains are fixed to the outer edge of a disk-shaped base metal, wherein the abrasive grain portion is provided with slits, and the number of slits is 0.16 ≦ the number of slits / abrasive grains. A grinding wheel in which the outer diameter (mm) of the part is 0.24 and the angle between the longitudinal center line of the slit and the radial direction of the base metal is 45 ° to 60 °.   The grinding wheel according to claim 1, wherein a width of the abrasive grain portion in a radial direction is 10 to 20 mm.   The grinding according to claim 1 or 2, wherein a boundary line between a portion where the slit is provided and a portion where the slit is not provided is parallel across the portion where the slit is provided in the abrasive grain portion. wheel.   The boundary line between the portion where the slit is provided and the portion where the slit is not provided in the abrasive grain portion is parallel across the portion where the slit is not provided. Grinding wheel.

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