JP4568596B2 - Polishing surface plate - Google Patents

Description

  The present invention relates to a polishing surface plate in which superabrasive pellets are attached to one side of a substrate. More specifically, the present invention relates to a polishing surface plate using superabrasive pellets used for polishing thin plate-like work materials such as hard and brittle materials and metal materials.

  A polishing surface plate represented by a surface plate used in double-head grinding, for example, in which superabrasive pellets are fixed to one surface of a disk-shaped substrate is known. This polishing surface plate can produce a wheel having a wide working surface at low cost by using pellets, can reuse the substrate to which the pellets are attached, and the density of the pellets (number of pellets per unit area). It has the advantage that the sharpness and life can be controlled by changing it, and is widely used for polishing hard and brittle materials and metal materials, especially thin plate-like work materials. As superabrasive grains to be used, it is known that CBN is suitable for iron-based work materials and diamond abrasive grains are suitable for other work materials. Moreover, a metal, resin, vitrified, etc. are used as a bond material for forming a pellet. Further, as a polishing method, there are infeed and throughfeed depending on how the work material is moved during polishing.

  By the way, as a polishing surface plate, sharpness and wear resistance are extremely important problems in terms of its function. As for the sharpness, there is a method for improving the sharpness by lowering the density of the pellets to lower the abrasive density. However, the interval between pellets, which lowers the density of the pellets, becomes wider, and the end of the workpiece that moves during polishing falls between the pellets and hits the next pellet as it is, so the workpiece is damaged and the flatness of the polished surface is also obtained. In some cases, the work material may break. In addition, the pellets are damaged and fall off, and when the pellets fall off, the phenomenon of the drop becomes worse.

  As for wear resistance, uneven wear is a problem. That is, when the same pellets are disposed on the substrate as a whole under various conditions such as the spacing, the wear is not always uniform and rather uneven wear often occurs. If uneven wear occurs, the flatness of the work material cannot be obtained, and it is necessary to re-grind the wheel to make the polished surface flat. Of course, it takes time and labor and the life of the wheel is shortened. In the following, as described above, when the same pellets are arranged as a whole under substantially the same conditions such as the interval, the area where the wear is relatively large is the area where the work is large with respect to the work material, and the wear is relative Region with a small amount is called a region with a small amount of work on the work material.

  In JP-A-11-165254, pellets are arranged radially to deal with uneven wear at the corners (edges) of the pellets arranged on the outermost and innermost circumferences of the grinding surface, and each radiation is arranged near the outer circumference. A configuration is shown in which pellets are further arranged between them to increase the arrangement density of the pellets, and a ring-shaped or segmented superabrasive layer is disposed on the outermost periphery and the innermost periphery.

JP-A-11-165254

  However, as described above, when the abrasive density is increased, the sharpness is deteriorated, so there is a limit to increasing the abrasive density at the inner and outer peripheral portions. Further, if it is intended to prevent uneven wear, it is necessary to balance the abrasive grains in the inner and outer peripheral parts and the part between them. The problem of falling of the cut work material is likely to occur.

  Furthermore, even if the same polishing surface plate is used, the portion where uneven wear occurs depends on the material, shape, size, polishing method or conditions of the work material, and depending on the case, uneven wear may occur in the central portion instead of the inner and outer peripheral portions. It may occur and the amount of uneven wear that occurs is also different.

  The present invention has been made in view of the above-described conventional problems, and it is an object of the present invention to provide a polishing surface plate that is excellent in sharpness, hardly causes uneven wear, and can polish a work material with good flatness. To do.

  In order to solve the above problems, in the polishing surface plate according to the present invention, in the polishing surface plate in which a plurality of superabrasive pellets are fixed to an annular region on one surface of a disk-shaped substrate, Pellets with relatively high wear resistance were placed in regions with a relatively large amount of work on the material, and pellets with relatively low wear resistance were placed on regions with a relatively small amount of work on the work material.

Specifically, the low wear-resistant pellet has an outer diameter of approximately the same length as the high wear-resistant pellet, and has a shape of an annular ring or a ring with a part of the ring cut out. is doing.

In the present invention, as described above, as the superabrasive pellets to be affixed on the substrate, relatively high wear-resistant pellets are used in a region having a large amount of work on the work material, and the work on the work material is relatively high. Pellets with relatively low wear resistance are used in a small area, so pellets with high wear resistance and low pellets according to the material, shape, size, polishing method, and polishing conditions of the work material It is possible to make the wear uniform by arranging them appropriately. Therefore, it is possible to maintain the pellet arrangement density to such an extent that the above-described cutting of the work material does not occur, and to obtain a good sharpness without excessively increasing the abrasive density. Furthermore, since it wears out uniformly as a whole and uneven wear does not occur, a high flatness is obtained for the work material. In addition, the number of operations for obtaining the flatness of the polished surface of the surface plate is reduced, the work efficiency is improved, and the life of the surface plate itself can be extended. And, as pellets with low wear resistance, pellets in the form of an annular ring with the same external dimensions as the high wear resistance pellet or a ring with a part of the ring cut out are used. The working area can be lowered without widening.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view with a part cut away, showing a polishing surface plate 1 according to a first embodiment of the present invention. The surface plate 1 includes a disk-shaped substrate 3 that can be formed using a known shape and material, and a large number of pellets 5 fixed to one surface thereof. In the present embodiment, the pellets 5 are concentric in the radial direction of the substrate 3 and are arranged in five rows of first row 7, second row 9, third row 11, fourth row 13, and fifth row 15 from the inside at equal intervals. Has been placed. The pellets 8, 10, 12, 14, 16 arranged in each row are arranged at substantially equal intervals in the circumferential direction in each row. The number of pellets arranged in each row is such that the intervals between the pellets in each row are close to each other.

  Of the five rows of pellets, the pellets 10, 12, and 14 arranged in the second, third, and fourth rows in the middle are diamond pellets that include diamond abrasive grains. So, metal bond is used as a binder. The shape is a conventionally known small disk shape. On the other hand, the pellets 8 and 16 in the first row and the fifth row on the inner peripheral side and the outer peripheral side include the same diamond abrasive grains as the pellets 10, 12, and 14, and are formed using the same metal bond. , 12 and 14 are formed in a ring shape. That is, as shown in FIG. 2, the pellets 8 and 16 are circular with the same radius as the pellets 10, 12, and 14, but the pellets 10, 12, and 14 are solidly formed. The center holes 8a1 and 6a are opened in the holes 8 and 16 to form an annular ring. In addition, arrangement | positioning of a pellet is not limited to 5 rows, The number can be increased as needed and the pellets 8 and 16 can be arrange | positioned only the desired row | line | column by the inner peripheral side and an outer peripheral side.

  FIG. 1 shows a work material W made of, for example, a glass plate, which is substantially square with a two-dot chain line. In the figure, the surface plate rotates in the direction of symbol A, and the work material W revolves in the direction of symbol A while rotating in the direction of symbol B while being held by a carrier (not shown). In the state shown in the figure, the length of the pellets in each row contacting the work material W is substantially the same, but in the state where the work material W has rotated 45 degrees from this state, the work of the first row and the fifth row of pellets is performed. The length of contact with the work material W is shortened and the work amount on the work material is relatively reduced, while that of the pellets in the second to fourth rows is longer and the work amount on the work material is increased. Therefore, when all the pellets are composed of the same diamond pellets, wear of the pellets in the central part is advanced and uneven wear occurs, but according to the present embodiment, the work amount on the work material is relatively small. The inner and outer peripheral pellets are ring-shaped and have lower wear resistance than the central row of pellets, and uneven wear does not occur. Therefore, the work material W can be supported uniformly, and a processed surface with high flatness can be obtained.

  FIG. 3 is an explanatory view of pellet arrangement showing pellets and their arrangement used in another embodiment. In this embodiment, the difference from the first embodiment described above is the shape of the pellets used in the first row and the fifth row. That is, the pellets used in the first row and the fifth row were annular rings in the first embodiment, whereas the pellets 31 in the first row and the fifth row in this embodiment, 39 is a ring with a part of the ring cut out. The pellets 31 in the first row are arranged with the notches 31a facing the center in the radial direction of the substrate, and the pellets 39 in the fifth row are arranged with the notches 39a facing outward in the radial direction. Yes.

  In the above description, the wear resistance is changed by changing the shape of the pellets and changing the area of each pellet that contacts the work material. However, the wear resistance is not limited to this. For example, the wear resistance may be changed by changing the concentration of abrasive grains, the grain size of abrasive grains, the type of abrasive grains, the amount of filler added, and the like.

  Further, in the above embodiment, the example has been described in which the inner and outer peripheral portions are regions with a relatively small amount of work with respect to the work material, and the central portion is a region with relatively large work amounts with respect to the work material. The invention is not limited to this. For example, when polishing with through-feed, the work material enters from the outside of the surface plate, so the work amount of the pellets arranged in the outer peripheral area to the work material is smaller than the pellets in other areas Therefore, for example, pellets with high wear resistance may be disposed in two rows on the outer peripheral side, and pellets with low wear resistance may be disposed on the inner peripheral row.

1 is a partially cutaway plan view showing a polishing surface plate according to a first embodiment of the present invention. It is a top view of the pellet with low abrasion resistance used with the surface plate of FIG. It is pellet arrangement explanatory drawing which shows the shape and arrangement | positioning of the pellet used by 2nd Embodiment.

Explanation of symbols

1: Polishing platen 3: Substrate 8: First row of pellets 10: Second row of pellets 12: Third row of pellets 14: Fourth row of pellets 16: Fifth row of pellets

Claims (2)

In a polishing surface plate in which a plurality of superabrasive pellets are fixed to an annular region on one surface of a disk-shaped substrate, a disk-shaped pellet is applied to a region where the work amount relative to the work material is relatively large. In the region where the amount of work on the cutting material is relatively small, it has an outer diameter of approximately the same length as the disk-shaped pellet, and is in the form of an annular ring or a ring with a part of the ring cut out. A polishing surface plate characterized by arranging pellets. 2. The polishing surface plate according to claim 1, wherein each of the pellets is formed to contain diamond abrasive grains .

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