JP6002343B1 - Polishing brush - Google Patents

Abstract

An object of the present invention is to provide a polishing brush capable of appropriately polishing an object having an uneven portion on the surface. A polishing brush according to the present invention is a polishing brush having a plurality of protrusions for polishing the surface of an object to be polished, which are spaced apart by a plurality of grooves, on the surface of the polishing layer. The volume is 55 to 95% with respect to the volume of the entire polishing region, and the polishing layer of the polishing brush is a first region located near the center of the polishing brush and a second region surrounding the first region. The first region has a first height from the bottom of the groove of the polishing layer of the first region to the top surface of the protrusion, and the polishing layer of the second region in the second region From the bottom of the groove to the top surface of the protrusion has a second height, and the first height and the second height are different. [Selection] Figure 4

Description

  The present invention relates to a polishing brush, and more particularly to a polishing brush that can appropriately polish an object to be polished having a convex portion on the surface.

  Conventionally, different types of mobile devices such as mobile phones, smartphones, tablet PCs, or various small portable electronic devices such as music players, game devices, or industrial systems are differentiated from other products. In order to achieve this, various shapes are adopted in its appearance and design. In recent years, as a shape of a small portable electronic device, a shape with a change in thickness, such as a shape in which a thickness is reduced toward the outer periphery and a curved surface is formed along the outer periphery, is frequently used. Moreover, by adopting such a shape, in addition to the effect of improving the designability, it is possible to provide an information display section on the side of the device or to provide a module such as an operation button. Can be improved.

  And when processing the housing | casing etc. of the small portable electronic device of the shape which gave the change as mentioned above, it is possible to use the technique of cutting and metal mold.

  When machining a shape with a change in thickness by cutting, the workpiece is cut into a predetermined shape using a ball end mill or an R-shaped diamond tool. However, when a ball end mill is used, arc-shaped cutting traces are formed on the processed surface in accordance with the ball diameter of the ball end mill. In addition, when an R-shaped diamond tool is used, it is necessary to form the flat surface and the curved surface by separate cutting processes, so a step is formed at the boundary line between the flat surface and the curved surface, and a uniform surface is processed. I can't. Similarly, when a shape having a change in thickness is formed by a mold, unevenness influenced by the surface quality of the mold is formed on the entire surface that is in contact with the mold.

  Therefore, as a means for removing the cutting traces, steps and irregularities generated by the above-described cutting and mold forming, the surface of the workpiece, that is, the object to be polished is polished using the polishing pad described in Patent Document 1 after the cutting. There is a need.

JP 2014-138974 A

  The polishing pad described in Patent Document 1 is formed as a multilayer structure including an elastic pad, a base layer, and an adhesive layer between them, and when an object to be polished (work) is pressed against the polishing pad, The polishing pad is configured to deform following the shape of the object to be polished.

  However, in recent years, various mobile devices such as mobile phones, smartphones, or tablet PCs as described above, or various small portable electronic devices such as music players, game devices, or industrial systems are manufactured on the surface. A maker name or brand name logo may be formed by a convex portion. In addition, the multi-functional mobile device and the small portable electronic device may be provided with a convex portion around each portion that accommodates a module such as an operation button provided in the device. is there. That is, there is a high tendency for convex portions to be formed in addition to a uniform surface (planar portion) in the housings of multifunctional mobile devices and small portable electronic devices.

  Thus, when the convex part is formed on the housing surface of the object to be polished, the polishing pad described in Patent Document 1 cannot sufficiently follow the structure of the convex part of the object to be polished. There has been a problem in that polishing spots are generated around the convex portion where the pad is difficult to contact.

  Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a polishing brush capable of appropriately polishing an object to be polished having a flat portion and a convex portion on the surface.

  In order to solve the above problems, the present invention provides a polishing brush having a plurality of protrusions for polishing the surface of an object to be polished, which are separated from each other by a plurality of grooves on the surface of the polishing layer. The volume of the polishing brush is 55 to 95% of the volume of the entire polishing region, and the polishing layer of the polishing brush surrounds the first region and the first region located near the center of the polishing brush. Including a second region, wherein the first region has a first height from the bottom of the groove of the polishing layer of the first region to the top surface of the protrusion, and the second region The region has a second height from the bottom of the groove of the polishing layer of the second region to the top surface of the protrusion, and the first height and the second height are different. It is characterized by.

  According to the present invention having the above configuration, the protrusion provided in the first region of the polishing brush and the protrusion provided in the second region of the polishing brush have different heights. The followability of the protrusions to the polished object is different. In particular, in the region of the polishing brush where the protrusion has a higher height, the protrusion has a higher followability to the object to be polished. In addition to polishing such a surface, it is possible to polish the convex part of the object to be polished by the region where the height of the protrusion of the polishing brush is large, and it is also possible to appropriately polish the object to be polished having the convex part on the surface. .

  In the present invention, the second height is greater than the first height.

  According to the present invention having the above-described configuration, the protrusion provided in the second region of the polishing brush has higher followability to the object to be polished than the protrusion provided in the first region of the polishing brush. In addition to polishing the uniform surface of the object to be polished by the first region of the polishing brush, the convex part of the object to be polished can be polished by the second region of the polishing brush. An abrasive can also be ground appropriately.

  In the present invention, the polishing layer of the polishing brush further includes a third region surrounding the second region, and in the third region, the groove of the polishing layer in the third region is formed. It is preferable that there is a third height from the bottom to the top surface of the protrusion, and the third height is smaller than the second height.

  According to the present invention configured as described above, the protrusions provided in the second region of the polishing brush are more polished than the protrusions provided in the first region and the third region of the polishing brush. Since the followability to the object is high, the uniform surface of the object to be polished is polished by the first region and the third region of the polishing brush, and the convex portion of the object to be polished is polished by the second region of the polishing brush. Therefore, an object to be polished having a convex portion on the surface can be appropriately polished.

  In the present invention, it is preferable that the third height is equal to the first height.

  According to the present invention configured as described above, since the first region and the third region are formed in the same manner, more uniform polishing can be performed in the first region and the third region. And a more uniform surface to be polished can be obtained on the surface of the object to be polished.

  In the present invention, in each region of the polishing layer, the opening area of the groove is preferably 65.00 to 99.99% with respect to a projected area when the polishing layer is viewed from above.

  According to the present invention configured as described above, a sufficient opening area of the groove can be ensured, whereby a sufficient amount of slurry can be supplied from the groove to the protrusion.

  Further, in the present invention, in each region of the polishing layer, the top surface of the protruding portion is formed flat, and the total area of the top surfaces of all the protruding portions is when the polishing brush is viewed from above. It is preferable that it is 0.01-35.00% with respect to a projection area.

  According to the present invention configured as described above, a sufficient amount of a polished surface can be secured, and thereby a decrease in the polishing rate for an object to be polished can be suppressed.

  Further, in the present invention, in each region of the polishing layer, the protrusion has a truncated polygon shape extending from the surface of the polishing layer, and a predetermined gap is provided between adjacent truncated polygons. Is preferably provided.

  According to the present invention configured as described above, the shape of the protruding portion is a truncated polygon, and a predetermined interval is provided between the truncated polygons so that an object to be polished is interposed between the protruding portions during polishing. The object to be polished can also be polished by the slope formed on the side surface of the protruding portion.

  Moreover, in this invention, it is preferable that the said polishing brush is further provided with the frame material arrange | positioned so that the said polishing layer may be enclosed along the periphery of the said polishing layer.

  According to the present invention configured as described above, the frame material arranged so as to surround the polishing layer serves as a weir, whereby the outflow of the slurry from the polishing layer can be controlled. Further, a large amount of slurry can be held on the polishing brush, and the polishing efficiency can be further increased.

  Preferably, the present invention is a polishing method using the polishing brush, wherein at least the convex portion of the object to be polished has a flat portion and a convex portion provided on the flat portion. The convex portion of the object to be polished is disposed in a position corresponding to the second region, and the polishing brush and the object to be polished move relative to each other to perform the polishing. It is a polishing method in which the convex portion of the object to be polished is pressed by a region and polished by the second region of the polishing brush.

  According to the present invention configured as described above, even if the object to be polished has a flat part and a convex part provided on the flat part, it is possible to appropriately prevent polishing spots from occurring around the convex part. And it can polish efficiently.

  As described above, according to the present invention, an object to be polished having a convex portion on the surface can be appropriately polished.

1 is a perspective view of a single-side polishing apparatus to which a polishing brush according to an embodiment of the present invention is applied. 1 is a top view of a polishing brush according to an embodiment of the present invention. It is a schematic sectional drawing of the III-III 'cross section of FIG. It is principal part sectional drawing of the polishing brush by embodiment of this invention. It is principal part sectional drawing which shows roughly the state at the time of grinding | polishing using the grinding | polishing brush by embodiment of this invention. It is a top view which shows the outline of the grinding | polishing method using the grinding | polishing brush by embodiment of this invention. It is principal part sectional drawing which shows the outline of the manufacturing method of the polishing brush by embodiment of this invention.

  Hereinafter, a polishing brush according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a single-side polishing apparatus to which the polishing brush according to the present embodiment is applied.

  As shown in FIG. 1, the single-side polishing machine 1 includes a polishing surface plate 5 having a disk-shaped polishing brush 3 fixed on the upper surface. A shaft 7 is provided at the bottom of the polishing surface plate 5, and the polishing surface plate 5 is configured to be able to rotate around the axis of the shaft 7. On the polishing brush 3, a polishing head 9 is disposed at a position eccentric from the axis of the shaft 7. The polishing head 9 has a holding plate 11 for holding an object to be polished (work). At the time of polishing, the object to be polished is pressed against the polishing brush 3 via the holding plate 11, and a predetermined amount is applied to the object to be polished. Polishing pressure can be applied. Further, at the time of polishing, the object to be polished is polished by rotating the shaft 7 around the axis while the slurry is supplied onto the polishing brush 3 by a slurry supply means (not shown). Although one polishing head 9 is shown in FIG. 1, a plurality of other polishing heads (not shown) can be arranged in an empty portion on the polishing brush 3.

  FIG. 2 is a top view of the polishing brush, and FIG. 3 is a cross-sectional view taken along the line III-III ′ of FIG. As shown in FIG. 2, a polishing layer 15 is disposed on the upper surface of the polishing brush 3, and the polishing layer 15 includes a circular first region 15 a located near the center of the polishing brush 3 and the first region. An annular second region 15b that concentrically surrounds the region 15a, and an annular third region 15c that concentrically surrounds the second region 15b. Although not shown in FIG. 2, the first region 15 a, the second region 15 b, and the third region 15 c open to the upper surface of the polishing brush 3, and then enter the polishing brush 3 from there. A plurality of grooves having a predetermined depth (referred to as grooves 13a, 13b, and 13c in the first region 15a, the second region 15b, and the third region 15c, respectively, and collectively referred to as the groove 13). ) Is formed. In addition, since the width | variety of each groove | channel is small enough with respect to the dimension of the polishing brush 3, it is not shown by FIG. ) The pattern drawn by the plurality of grooves may be a lattice shape. A plurality of projections described later are separated and defined by the plurality of grooves. An annular frame member (not shown) that functions as a weir for controlling the outflow of the slurry may be provided around the polishing layer 15 of the polishing brush 3. By providing such a frame material, a large amount of slurry can be held on the polishing brush, and the polishing efficiency can be further increased.

  The diameter of the first region 15a, the width of the second region 15b, and the width of the third region 15c are preferably changed according to the size of the object to be polished. In particular, the width of the second region 15b preferably has such a width that the convex portion of the object to be polished can be polished by the second region 15b during polishing of the object to be polished.

  As shown in FIG. 3, the polishing brush 3 includes a polishing layer 15 formed of a resin-impregnated nonwoven fabric or foamed polyurethane having a thickness of 1 to 6 mm and a radius of 460 mm, and a cushion layer 17 formed of a polyethylene foam sheet or a polyurethane sheet, for example. Are formed as a whole and have a disk shape as a whole. The polishing layer 15 and the cushion layer 17 are bonded to each other via an adhesive layer 19 such as a double-sided tape or an adhesive having a core material of a flexible film such as PET (polyethylene terephthalate) or polypropylene. And the double-sided tape 21 for affixing the grinding | polishing brush 3 to the grinding | polishing surface plate 5 is affixed on the surface of the cushion layer 17 which is not facing the grinding | polishing layer 15. FIG.

  FIG. 4 is a cross-sectional view of the main part of the polishing layer 15 of the polishing brush 3 near the boundary between the first region 15a and the second region 15b. As shown in FIG. 4, the first region 15a and the second region 15b of the polishing layer 15 of the polishing brush 3 are formed with a plurality of protrusions 25a and 25b that are separated by grooves 13a and 13b, respectively. Yes. Although not shown in FIG. 4, a plurality of protrusions 25c and grooves 13c are formed in the third region 15c as well. (The projecting portions 25a, 25b, and 25c are collectively referred to as the projecting portion 25.) That is, the plurality of projecting portions 25 of the polishing layer 15 of the polishing brush 3 of the present invention are formed from the same continuous material.

  The plurality of protrusions 25a, 25b, and 25c are defined by grooves 13a, 13b, and 13c provided in a lattice shape, and these grooves 13a, 13b, and 13c serve to store slurry in the polishing region. . The polishing region refers to a region located between the bottom 31 of the groove 13 of the polishing brush 3 and the polishing surface 27, which will be described in detail later.

  Each protrusion 25a, 25b, 25c has a plurality of openings (not shown) on the surface so that polishing can be performed by the slurry held in the openings and the slurry stored in the polishing region. It has become. Each protrusion 25a, 25b, 25c extends from the surface of the polishing layer 3 in a direction away from the polishing surface plate 5. Each protrusion 25a, 25b, 25c has, for example, a truncated quadrangular pyramid shape, and each top surface 27a, 27b, 27c (not shown) of each protrusion 25a, 25b, 25c is a polishing brush as a whole. 3 polishing surface 27 is formed. Although details will be described later, the inclined surfaces 29a, 29b forming the side surfaces of the truncated quadrangular pyramidal projections 25a, 25b, 25c and the inclined surface 29c (not shown) also have a polishing action during polishing.

  As shown in FIG. 4, in the first region 15a, a first height Ha from the bottom 31a of the groove 13a of the polishing layer 15 to the top surface 27a of the protrusion 25a is defined, and the interval between the protrusions 25a is defined. Wa is defined. Also in the second region 15b, a second height Hb from the bottom 31b of the groove 13b of the polishing layer 15 to the top surface 27b of the protrusion 25b is defined, and an interval Wb between the protrusions 25b is defined. Similarly, in the third region 15c (not shown), the third height Hc from the bottom 31c of the groove 13c of the polishing layer 15 to the top surface 27c of the protrusion 25c is defined, and the interval Wc between the protrusions 25c is defined. Is defined. (The bottom portions 31a, 31b, and 31c are collectively referred to as the bottom portion 31.)

  The polishing brush 3 according to the present invention preferably satisfies the relationship Ha <Hb. In other words, the second height is preferably larger than the first height. Further, the polishing brush 3 according to the present invention satisfies the relationship of Hc <Hb. That is, the third height is smaller than the second height. As for the relationship between Ha and Hc, it is preferable that Ha = Hc, that is, the first height and the third height are equal, but Ha <Hc or Ha> Hc may be satisfied. . When the first height and the third height are equal, more uniform polishing can be performed in the first region and the third region, and a more uniform surface to be polished can be obtained on the surface of the object to be polished. Can do. Although not shown, as a modification of the present embodiment, the third region 15c can be omitted, and the polishing layer 15 of the polishing brush 3 can be configured by the first region and the second region described above. is there.

  On the other hand, as will be described later with reference to FIG. 7 regarding the manufacturing method of the polishing brush 3 of the present invention, the groove 13 has a predetermined depth while pressing the rotary blade 55 having the same tip shape vertically against the polishing layer 15. It is cut and formed by moving with. Therefore, the intervals Wa, Wb, Wc described above are determined by the shape of the tip of the rotary blade 55. According to the manufacturing method described later, since the grooves 13 in each region are formed using the rotary blade 55 having the same tip shape, Wa, Wb, and Wc are equal. (Hereinafter referred to as the interval W collectively.)

  The depth at which the rotary blade 55 is pressed against the polishing layer 15 is made deeper in the second region 15b than in the other regions, so that the first height related to the groove 13a, groove 13b, and groove 13c formed by cutting formation is increased. Differences occur in the height Ha, the second height Hb, and the third height Hc. At this time, since the rotary blade 55 is pressed deeper than the other regions in the second region 15b, the top surface 27b of the protrusion 25b is formed on the top of the other protrusions 25a and 25c by the inclined side surface of the rotary blade 55. More than the surfaces 27a and 27c. For this reason, the area of the top surface 27b of the protrusion 25b is smaller than the areas of the top surfaces 27a and 27c of the other protrusions 25a and 25c. That is, the shape of the top surface 27b of the protrusion 25b is different from the shape of the top surfaces 27a and 27c of the protrusions 25a and 25c, and the protrusion 25b is more elongated than the protrusions 25a and 25c. Will have.

  By having such a configuration, the protrusion 25b of the second region 15b has a more elongated shape than the protrusion 25a of the first region 15a and the protrusion 25c of the third region 15c. Compared with the protrusion 25a of the first region 15a and the protrusion 25c of the third region 15c, the followability of the protrusion 25b of the second region 15b to the object 33 is improved.

  The total volume of the grooves 13 formed in the polishing brush 3 occupies 55 to 95%, preferably 60 to 90%, more preferably 65 to 85% with respect to the volume of the polishing region. The polishing region refers to a region in the portion between the bottom 31 of the groove 13 of the polishing brush 3 and the polishing surface 27. In other words, the volume of the polishing region is the projected area when the polishing brush 3 is viewed from above (the square of the radius of the polishing brush 3 multiplied by the circumference ratio π), the first region 15a, and the first region 15a. For each of the second region 15b and the third region 15c, the height from the bottom 31 (31a, 31b, 31c) of the groove 13 (13a, 13b, 13c) to the polishing surface 27 (top surfaces 27a, 27b, 27c) H (Ha, Hb, Hc) is multiplied and added. According to the knowledge of the inventors, a sufficient amount of slurry can be stored by setting the volume of the groove 13 to 50 to 95% with respect to the volume of the entire polishing region. The width of each groove 13a, 13b, 13c becomes narrower toward the bottom, but the opening area of the groove 13 at the height of the polishing surface 27 of the polishing brush 3 is relative to the projected area when the polishing brush 3 is viewed from above. It is preferable that it is 65.00 to 99.99%.

  In the first region 15a, the ratio Ha / Ra between the height Ha of the protrusion 25a and the radius Ra of the circumscribed circle in the horizontal cross-sectional shape of the protrusion base is preferably in the range of 0.3 to 2.0. If it is the above-mentioned range, it will be excellent in the followability to the to-be-polished object 33, and will be excellent in smoothness.

  In the second region 15b, the ratio Hb / Rb between the height Hb of the protrusion 25b and the radius Rb of the circumscribed circle in the cross-sectional shape of the protrusion base is preferably in the range of 0.5 to 3.0. If it is the above-mentioned range, it will be excellent in the follow-up property to the to-be-polished object 33, especially the follow-up property to the convex part which the to-be-polished object 33 has, and excellent in smoothness.

  In the third region 15c, the ratio Hc / Rc between the height Hc of the protrusion 25c and the radius Rc of the circumscribed circle in the cross-sectional shape of the protrusion base is preferably in the range of 0.3 to 2.0. The value of the ratio Hc / Rc is preferably equal to the value of the ratio Ha / Ra described above. However, if the ratio is within the above-described range, the followability to the workpiece 33 is excellent and the smoothness is excellent.

  The shape of the grooves 13a, 13b, and 13c described above is complementary to the shape of the protrusions 25a, 25b, and 25c. For example, the protrusion 25 is a truncated triangular pyramid and is arranged to draw a triangular lattice. In this case, the grooves 13 formed between the protrusions 25 draw a triangular lattice on the surface of the polishing layer 15. Further, when the protrusion 25 is a truncated hexagonal pyramid and is arranged so as to draw a hexagonal lattice, the groove draws a hexagonal lattice on the surface of the polishing layer. The shape of the protrusion 25 or the shape drawn by the groove 13 can be appropriately changed according to the required polishing rate, the area of the polishing surface 27, and the volume of the groove 13.

  The protrusions 25a, 25b, and 25c each have a flat top surface (27a, 27b, 27c) that constitutes the polishing surface 27, and a plurality of inclined surfaces 29a that are inclined from the top surfaces and extend toward the bottom 31 of the groove 13. , 29b, 29c (not shown). The heights Ha, Hb, and Hc of the protrusions 25a, 25b, and 25c satisfy, for example, 1 to 5 mm or 30 to 30 mm with respect to the thickness of the polishing layer 15 while satisfying the relationship of Ha <Hb and Hc <Hb. 90%, the interval W between the protrusions 25 is 2 to 5 mm, and the top surface constituting the polishing surface 27 is a square having a side of 0.1 to 5 mm. The difference between Hb and Ha (and Hc) is preferably about 1.0 to 3.0 mm. The area of the polishing surface of the polishing brush 3 is the total area of the top surfaces of all the protrusions 25, and the area of the polishing surface 27 is 0.01 to 35 with respect to the projected area when the polishing brush 3 is viewed from above. It is preferably 0.000%. By setting the heights Ha, Hb, Hc, the interval W, and the area of each protrusion 25a, 25b, 25c within the above ranges, the wear resistance of the protrusion 25 and the shape of the object to be polished during polishing are tracked. Can be improved.

  By setting the area of the groove 13 and the area of the polishing surface 27 in the above ranges, both supplying a sufficient amount of slurry from the groove 13 to the polishing surface 27 and ensuring a sufficient amount of the polishing surface 27 are achieved. Can be achieved.

  Further, the depths of the grooves 13a, 13b, 13c or the heights Ha, Hb, Hc of the protrusions 25a, 25b, 25c are within the above ranges, and the top surfaces 27a, 27b, 27c of the protrusions 25a, 25b, 25c are respectively By making a square with a side of 0.1 to 5 mm, the projecting portion 25 is prevented from being damaged and the projecting portion 25 from falling off the polishing brush 3 while ensuring the deformability of the projecting portion 25 during polishing. Can do.

  FIG. 5 is a cross-sectional view of the main part showing a state in the vicinity of the first region 15a of the polishing layer 15 of the polishing brush 3 during polishing. In FIG. 5, at the time of polishing, the object to be polished 33 moves in the horizontal direction while being pressed onto the top surface (that is, the polishing surface) 27a. Outside the range of FIG. 5, the workpiece 33 moves in the horizontal direction while being pressed onto the top surface 27b in the second region 15b and on the top surface 27c in the third region 15c. Of the plurality of protrusions 25, those that are in contact with the object to be polished 33 are compressed by the object to be polished 33, and those that are not in contact with the object to be polished 33 are not crushed, The original height Ha (Hb in the second region 15b and Hc in the third region 15c) is maintained. Then, as shown in FIG. 5, when the workpiece 33 moves on the polishing brush 3 in the horizontal direction, the top surface 27 a of the compressed projection 25 a and the projection having the height Ha are maintained. It contacts the inclined surface 29a of 25a. Such an operation is the same in the second region 15b and the third region 15c. Thereby, the to-be-polished object 33 can be grind | polished suitably.

  Thus, the same contact state occurs in the first region 15a, the second region 15b, and the third region 15c of the polishing layer 15 during polishing, but the height Hb of the protrusion 25b of the second region 15b is The heights Ha and Hc of the projections 25a and 25c of the first region 15a and the third region 15c are larger than the projections 25a and 25c of the other regions. Thus, the protrusion 25b of the second region 15b has higher followability to the object 33 than the protrusion 25a of the first region 15a and the protrusion 25c of the third region 15c. . As will be described later with reference to FIG. 6, the convex portion of the object to be polished 33 is pressed against the second region 15 b, and the other region (uniform surface) of the object to be polished 33 is moved to the first region 15 a or the third region. By polishing against the region 15c, the uniform surface (planar portion) of the object to be polished 33 is polished, and also closely follows the protrusions of the object to be polished 33, so that the surface has protrusions. An object to be polished can also be properly polished.

  At this time, the slurry supplied to the polishing brush 3 passes through the plurality of grooves 13 to every corner of the polishing brush 3, or a sufficient amount of slurry is applied to the polishing surface 27 of all the protrusions 25. Can be supplied.

  As described above, according to the polishing brush 3 according to the present embodiment, a sufficient amount of the polishing surface area can be ensured to obtain a predetermined polishing rate, and a sufficient amount of slurry is applied to the polishing brush 3. Can be held in.

  A specific polishing method will be described as follows with reference to FIG. FIG. 6 is a top view schematically showing a polishing method using the polishing brush according to the embodiment of the present invention. As described above, the polishing brush 3 has a disk shape and is fixed to the upper surface of the polishing surface plate 5 (not shown). The polishing layer 15 of the polishing brush 3 includes a first region 15a located near the center of the polishing brush 3, an annular second region 15b surrounding the first region, and an annular third region surrounding the second region. A region 15c is provided.

  On the other hand, the polishing head 9 (only the contour line seen from the upper surface is shown in FIG. 6) holds the object to be polished 33. In the present embodiment, as the object to be polished 33, for example, a housing having a convex portion is polished. The object to be polished 33 has a convex portion 35 in the center as shown in FIG. 6, for example. Specifically, the convex portion 35 includes a bulge around each portion having the convex portion provided on the housing in the portable electronic device.

  As shown in FIG. 6, one polishing head 9 holds one workpiece 33. In the present embodiment, the object to be polished 33 is arranged so that the convex portion 35 of the object to be polished 33 is located at the center of the polishing head 9.

  When the workpiece 33 is polished with the polishing brush 3, the polishing head 9 is first positioned with respect to the polishing brush 3. In this positioning, the portion to be polished of the workpiece 33 held by the polishing head 9 enters the range of the polishing brush 3, and at least the convex portion 35 of the workpiece 33 corresponds to the second region 15 b of the polishing brush 3. This is done by placing it in position.

  When the polishing surface plate 5 on which the polishing brush 3 is fixed rotates, relative movement occurs between the object to be polished 33 held by the polishing head 9 and the polishing brush 3. Then, the polishing object 9 is polished by supplying the slurry onto the polishing layer 15 by a slurry supply means (not shown) while pressing the polishing object 33 against the polishing layer 15 by the polishing head 9. At this time, at least the convex portion 35 of the workpiece 33 is pressed against the second region 15b of the polishing layer 15 by the positioning described above, and the convex portion 35 is polished by the second region 15b. The other planar portion of the object to be polished 33 is polished by the first region 15a, the second region 15b, or the third region 15c of the polishing layer 15. As described above, the protrusions 25b of the second region 15b have better followability to the object to be polished 33 than the protrusions of other regions, and follow the protrusions 35 well. Even the object 33 to be polished having the convex portions 35 can be polished appropriately and efficiently while preventing the occurrence of polishing spots around the convex portions 35.

  Although FIG. 6 shows a state where one polishing head 9 is used, another polishing head 9 is arranged in an empty space and polishing is performed using a plurality of polishing heads 9 at a time. It is also possible. Further, it is possible to perform polishing by arranging a plurality of objects to be polished on one polishing head 9 so that convex portions are gathered at the center.

  Next, with reference to FIG. 7, an embodiment of a method for manufacturing a polishing brush according to an embodiment of the present invention will be described. FIG. 7 is a cross-sectional view of an essential part showing an outline of a manufacturing method of a polishing brush according to an embodiment of the present invention, and shows a processing step of the polishing layer 15 of the polishing brush 3. As will be described later, the polishing layer 15 according to the embodiment of the present invention forms a groove by pressing the rotary blade 55 against the flat polishing layer 15 and moving it at a predetermined depth. The parts are separated and defined. Usually, the height of each projection is controlled by the pressing depth of the rotary blade 55 against the polishing layer 15.

  FIG. 7 is a cross-sectional view of an essential part showing an outline of a method for manufacturing a polishing brush according to an embodiment of the present invention. It is sectional drawing which shows the state pressed. For easy understanding, the interval between the positions where the rotary blade 55 is pressed is different from the actual one. As shown in FIG. 7, the rotary blade 55 is pressed against the polishing layer 15 in the direction indicated by the arrow, that is, in the vertical downward direction. The moving distance of the rotary blade 55 when pressing the rotary blade 55 against the polishing layer 15 is controlled based on the distance of the rotary blade 55 relative to the support base 51. In the present embodiment, the second region 15b is the first region 15a. The rotary blade 55 has entered the lower position.

  In the region shown on the left side of FIG. 7, that is, the region corresponding to the first region 15a, the rotary blade 55 enters the support base 51 and is pressed against the polishing layer 15 to perform cutting. FIG. 7 shows a state when the rotary blade 55 comes closest to the support base 51 by this cutting operation. In the region corresponding to the first region 15a, the rotary blade 55 is pressed against the polishing layer 15, and the depth from the upper surface of the polishing layer 15 at the point where the end of the rotary blade 55 is closest to the support base 51 is This corresponds to the height Ha of the protrusion 25a formed in one region 15a. When the rotary blade 55 moves at a predetermined depth, a groove 13a having a depth Ha is formed in the locus.

  In the region shown on the right side of FIG. 7, that is, the region corresponding to the second region 15b, the rotary blade 55 similarly moves toward the support base 51 and is pressed against the polishing layer 15 to perform cutting. Also in the region shown on the right side of FIG. 7, the state when the rotary blade 55 comes closest to the support base 51 during this cutting operation is shown. In the region corresponding to the second region 15b, the moving distance of the rotary blade 55 relative to the support base 51 is larger than the region corresponding to the first region 15a. The depth from the upper surface of the polishing layer 15 at the point where the tip end is closest to the support base 51 is Hb deeper than Ha. When the rotary blade 55 moves at a predetermined depth, a groove 13b having a depth Hb is formed on the locus.

  A series of cutting operations for moving the rotary blade 55 at a predetermined depth while pressing the rotary blade 55 in the first region 15a, the second region 15b, and the third region 15c are common. When the process is completed once, the support base 51 is relatively moved in the horizontal direction while the rotary blade 55 is then pulled upward, and positioned at the position where the next groove 13 is formed, and the same cutting operation is performed. By repeating this operation, a plurality of grooves 13 are formed on the surface of the polishing layer 15. When a plurality of parallel grooves 13 are formed over the entire surface of the polishing layer 15 by the relative movement in the horizontal direction, the polishing layer 15 is then rotated by 90 degrees relative to the rotary blade 55 and is already formed. It operates to form grooves 13 that are orthogonal to the plurality of grooves 13. The cutting operation of the rotary blade 55 after being rotated by 90 degrees is the same as the cutting operation of the rotary blade 55 described above. Thereby, the lattice-like grooves 13 are formed over the entire surface of the polishing layer 15, that is, the protrusions 25 are formed over the entire surface of the polishing layer 15.

  After the formation of the groove 13 using the rotary blade 55 is finished, the polishing layer 15 is removed from the support base 51, and the polishing layer 15 is bonded onto the cushion layer 17 of the polishing brush 3 described above via the adhesive layer 19. Thus, the polishing layer 15 of the polishing brush 3 as shown in FIG. 3 is obtained.

  As described above, the embodiment of the present invention has been described. However, as a modification, the height of the protrusion in the first region of the polishing brush is made larger than the height of the second protrusion, contrary to the above-described embodiment. It is also possible. By changing the height between the protrusion provided in the first region of the polishing brush and the protrusion provided in the second region of the polishing brush, the followability to the object to be polished becomes different. In the example, the convex portion of the object to be polished can be polished by the first region having a high height of the polishing brush, and the object to be polished having the convex portion on the surface can be appropriately polished. It is preferable to use a polishing brush of such a modification as appropriate depending on the shape of the object to be polished and the position of the convex portion.

3 polishing brush 9 polishing head 13 groove 15 polishing layer 15a first region 15b second region 15c third region 25 protrusion 25a first region protrusion 25b second region protrusion 25c third region Projection portion 27 Polishing surface 29 Inclined surface 31 Groove bottom portion 33 Object to be polished 35 Convex portion 51 Support base 55 Rotary blade

Claims (9)

A polishing brush having a plurality of protrusions for polishing the surface of an object to be polished, separated by a plurality of grooves on the surface of the polishing layer,
The volume of the groove is 55 to 95% with respect to the volume of the entire polishing region,
Furthermore, the polishing layer of the polishing brush includes a first region located near the center of the polishing brush and a second region surrounding the first region,
The first region has a first height from the bottom of the groove of the polishing layer of the first region to the top surface of the protrusion,
The second region has a second height from the bottom of the groove of the polishing layer of the second region to the top surface of the protrusion,
The polishing brush, wherein the first height and the second height are different.   The polishing brush according to claim 1, wherein the second height is greater than the first height.   The polishing layer of the polishing brush further includes a third region that surrounds the second region, and in the third region, from the bottom of the groove of the polishing layer of the third region, The polishing brush according to claim 2, wherein the polishing brush has a third height up to the top surface, and the third height is smaller than the second height.   The polishing brush according to claim 3, wherein the third height is equal to the first height.   The opening area of the groove in each region of the polishing layer is 65.00 to 99.99% with respect to a projected area when the polishing layer is viewed from above. The polishing brush according to item.   In each region of the polishing layer, the top surface of the projection is formed flat, and the total area of the top surfaces of all the projections is 0 with respect to the projected area when the polishing brush is viewed from above. The polishing brush according to any one of claims 1 to 5, which has a content of 0.01 to 5.00%.   In each region of the polishing layer, the protrusion has a truncated polygon shape extending from the surface of the polishing layer, and a predetermined interval is provided between adjacent truncated polygons. The polishing brush according to any one of claims 1 to 6.   The polishing brush according to any one of claims 1 to 7, further comprising a frame member disposed so as to surround the polishing layer along a periphery of the polishing layer. Among the objects to be polished having a flat part and a convex part provided on the flat part, at least the convex part is arranged at a position corresponding to the second region of the polishing brush,
While the polishing brush and the object to be polished move relative to each other, the protrusion of the object to be polished is pressed against the second region of the polishing brush, and the protrusion of the object to be polished is performed. A polishing method using the polishing brush according to any one of claims 1 to 8, wherein polishing is performed by the second region of the polishing brush.