JP2014014878A - Grinding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of abnormal wear or poor grinding of a griding stone by avoiding inclination of a rotational axis of a grinding spindle unit in a grinding device.SOLUTION: Regarding a grinding device 1 constituted to bring a grinding stone 320 fixed to a grinding wheel 32 attached to a grinding spindle 30 into contact with a plate-like work held by a holding table 2 to be pressed by grinding feeding means 4, the grinding stone 320 presses the top face of the plate-like work by arranging the respective axial centers 40a of two guides 40 for guiding elevation of the grinding spindle 30, and an axial center 41a of a back and forth axis 41 for elevating the grinding spindle 30 on one reference straight line 200, and arranging the reference straight line and a string connecting the start point and the end point of a grinding area where the top face of the plate-like work contacts the grinding stone in parallel with each other, and inclination of the rotational axis 300 of the grinding spindle 30 is prevented when the holding table 2 is pressed by its grinding load to prevent generation of abnormal wear or poor grinding of the grinding stone 320.

Description

  The present invention relates to a grinding apparatus for grinding a plate-like workpiece.

  BACKGROUND ART A grinding apparatus for grinding a plate workpiece such as a semiconductor wafer includes a holding table that holds the plate workpiece and a grinding spindle unit on which a grinding wheel is mounted at a lower end portion. For example, in the grinding apparatus described in Patent Document 1, a grinding spindle unit is supported by a grinding holder, and the grinding holder is supported in a cantilever manner so that it can be moved up and down by a grinding feed means having an advance / retreat shaft and a guide, As the grinding holder moves up and down driven by the grinding feed means, the grinding spindle unit also moves up and down.

JP 2011-161546 A

  However, in the above grinding apparatus, when the plate-like workpiece held on the holding table is ground, the portion where the grinding wheel provided on the grinding wheel and the plate-like workpiece are in contact with each other and the vertical movement of the grinding spindle unit are guided. Since the guide, the advancing / retracting axis for moving the grinding holder up and down, and the center of gravity of the grinding spindle unit are not arranged in a straight line, the rotation axis of the grinding spindle unit is inclined due to the load applied to the grinding wheel, causing abnormalities in the grinding wheel There is a problem that wear and grinding failure occur.

  The present invention has been considered in view of such problems, and it is an object of the present invention to prevent abnormal grinding of grinding wheels and poor grinding from occurring in a grinding apparatus by preventing the rotation shaft of the grinding spindle unit from tilting. And

  The present invention relates to a rotatable holding table for holding a plate-like workpiece, a grinding means for grinding the plate-like workpiece held on the holding table, and a grinding feed direction for causing the grinding means to approach or separate from the holding table. Grinding feeding means for advancing and retreating, and positioning means for relatively positioning a plate-like work held by a holding table to a position facing a grinding wheel arranged in an annular shape on a grinding wheel mounted on the grinding means, and holding In a grinding apparatus for in-feed grinding the upper surface of a plate-like workpiece held by a table by a grinding means, the grinding means includes a grinding spindle having a rotating shaft on which a grinding wheel is mounted, a spindle holder that supports the grinding spindle, The grinding feed means is arranged in parallel with the grinding feed direction and moves up and down of the spindle holder. The guide is composed of two guides, and a forward / backward shaft for moving the spindle holder directed by the two guides back and forth in the grinding feed direction, and each shaft center of the two guides and the axis of the forward / backward shaft The center of the grinding region is arranged on one reference straight line, and connects the reference straight line and the starting point and the end point of the arc-shaped grinding region where the upper surface of the plate-like workpiece held by the holding table contacts the grinding wheel. The strings are arranged in parallel.

  The grinding apparatus includes two guides and an advancing / retracting shaft for grinding and feeding the grinding means, and two column portions that respectively support the two guides, and a connecting portion that connects the upper portions of the two column portions. When it is provided with a portal column constituted by, it is desirable that the centroid of the column cross section of the column is arranged on the reference straight line. In addition, it is desirable that the midpoint of the chord in the grinding region forming the arc shape coincides with the axis of the advance / retreat axis. Further, the positioning means includes a Y moving means for moving the grinding means in the Y-axis direction, which is a direction for approaching and separating from the holding means, and an X moving means for moving the holding means in the X-axis direction orthogonal to the Y moving means. It is desirable to be composed of

  In the present invention, the axis of each of the two guides for guiding the vertical movement of the spindle holder and the axis of the advancing / retreating axis for advancing and retracting the spindle holder in the grinding feed direction are arranged on one reference straight line. Since the straight line and the string connecting the starting point and the ending point of the arc-shaped grinding area where the upper surface of the plate-shaped workpiece and the grinding wheel come in contact are arranged in parallel, the holding table is applied by the grinding load when grinding the plate-shaped workpiece Even if pressed, the rotation axis of the grinding spindle is difficult to tilt, and it is possible to prevent abnormal grinding of the grinding wheel and poor grinding.

  A gate comprising two guides and an advancing / retracting shaft for grinding and feeding the grinding means, and comprising two column parts respectively supporting the two guides and a connecting part connecting the upper parts of the two column parts When the mold column is provided, the centroid of the column cross-section of the column part is arranged on the reference straight line, so that the column part is not inclined, so that the grinding means can be prevented from being inclined in the reference straight line direction. .

  If the midpoint of the chord of the grinding area forming the arc shape coincides with the axis of the advance / retreat axis, the grinding feed means 4 can be more reliably prevented from tilting, and the plate-like workpiece Surface accuracy can be maintained.

  The positioning means includes a Y moving means that moves the grinding means in the Y-axis direction, which is a direction in which the grinding means approaches and separates from the holding means, and an X moving means that moves the holding means in the X-axis direction orthogonal to the Y moving means. If comprised, it can respond to the change of the diameter of the plate-shaped workpiece | work hold | maintained by a holding means or a grinding wheel.

It is a perspective view which shows an example of a grinding device. It is a cross-sectional view which shows typically the 1st example of the positional relationship of a holding table, a grinding means, and a grinding feed means. It is a cross-sectional view schematically showing a second example of the positional relationship among the holding table, the grinding means, and the grinding feed means. It is a cross-sectional view schematically showing a third example of the positional relationship among the holding table, the grinding means, and the grinding feed means.

  A grinding apparatus 1 shown in FIG. 1 includes a holding table 2 that holds a plate-like workpiece, a grinding means 3 that grinds the plate-like workpiece held by the holding table 2, and the grinding means 3 that approaches the holding table two times. Alternatively, it is provided with a grinding feed means 4 for moving back and forth in the grinding feed direction (Z-axis direction) that moves away.

  The holding table 2 is rotatable and is horizontally moved in the front-rear direction (Y-axis direction) with the expansion and contraction of the bellows-shaped cover member 21 by being driven by the positioning means 20. The holding surface 2a of the holding table 2 is formed in a conical surface having the rotation center as a vertex.

  The grinding means 3 includes a grinding spindle 30 having a rotating shaft 300 on which a grinding wheel 32 is mounted and a rotatable shaft, and a spindle holder 31 that supports the grinding spindle 30. On the lower surface of the grinding wheel 32, a grinding wheel 320 having a predetermined width in the radial direction around the axis 300a of the rotating shaft 300 is fixed on an arc.

  The grinding feed means 4 supports the spindle holder 31 so as to move up and down, and advances and retracts the two guides 40 arranged in parallel to the grinding feed direction and the spindle holder 40 directed by the two guides in the grinding feed direction. An advance / retreat axis 41 is provided. The advance / retreat shaft 41 is screwed into a nut structure provided inside the spindle holder 31.

  The two guides 40 and the advancing / retreating shaft 41 constituting the grinding feed means 4 are disposed in a portal column 42 disposed across the movement path of the holding means 2 in the Y-axis direction. The portal column 42 includes a column portion 420 that supports the two guides 40 and a connecting portion 421 that connects the upper portions of the two column portions 420.

  At the time of grinding the plate-like workpiece, first, the positioning means 20 shown in FIG. 1 positions the plate-like workpiece W held by the holding table 2 at a grinding position facing the grinding wheel 320 as shown in FIG. . When the holding table 2 rotates in a state where it is located at the grinding position, the rotating shaft 300 of the grinding means 3 rotates, and when the grinding feed means 4 grinds and feeds the grinding means 3 in the Z direction at a predetermined speed, the holding table 2 Since the holding surface 2a is a conical surface, the upper surface of the plate-like workpiece W and the lower surface of the grinding wheel 320 have the width of the grinding wheel 320 in the radial direction of the grinding wheel 32 about the axis 300a of the rotating shaft 300. In contact grinding in the grinding region 100 from the rotation center of the holding table 2 to the outer peripheral edge of the plate-like workpiece W, the upper surface of the plate-like workpiece W is pressed and in-feed grinding is performed. Further, the holding table 2 positioned at the grinding position is also pressed by the grinding load at that time.

  At this time, as shown in FIG. 2, the axis 40 a of each of the two guides 40 and the axis 41 a of the advance / retreat axis 41 are arranged on one reference straight line 200. Further, the reference straight line 200 and the string 100a connecting the start point and the end point of the arc-shaped grinding region 100 where the upper surface of the plate-like workpiece W held by the holding table 2 and the grinding wheel 320 come into contact with each other are parallel. In the example of FIG. 2, the reference straight line 200 and the string 100a coincide. Therefore, even if the holding table 2 is pressed by the grinding load and a load is applied to the grinding wheel 320, the grinding feed means 4 does not incline, so the rotary shaft 300 of the grinding spindle 30 supported by the grinding feed means 4 inclines. It is difficult to prevent abnormal wear of the grinding wheel 320 and poor grinding.

  Further, in the example of FIG. 2, the centroid 420a of the column 420 is disposed on the reference straight line 200, and the midpoint of the string 100a coincides with the axis 41a of the advance / retreat axis 41. Inclination of the means 4 can be prevented more reliably, and the surface accuracy of the plate-like workpiece can be maintained.

  The holding table 2 of the grinding apparatus 1a shown in FIG. 3 holds a plate-like workpiece W1 having a smaller diameter than the plate-like workpiece W shown in FIG. The axis 40a of each of the two guides 40, the axis 41a of the advance / retreat axis 41, and the centroid 420a of the two column portions 420 are arranged on one reference straight line 201. The reference straight line 201 and the chord 101a connecting the start point and the end point of the arc-shaped grinding region 101 where the upper surface of the plate-like workpiece W and the grinding wheel 320 are in contact with each other are parallel to each other. Therefore, it is possible to more reliably prevent the rotation shaft 300 of the grinding spindle 30 from being inclined, and it is possible to prevent abnormal wear or grinding failure of the grinding wheel 320.

  In order to achieve such a positional relationship, the Y axis is inclined in the grinding apparatus 1a. Further, in order to realize such a positional relationship, the holding table 2 and the grinding means 3 may be relatively moved in the X-axis direction. For example, instead of the positioning means 20 shown in FIG. 1, a Y moving means for moving the grinding means 3 in the Y axis direction, which is a direction in which the grinding means 3 approaches and separates from the holding means 2, and the holding means in the Y axis direction Positioning means is constituted by X moving means that operates in the X-axis direction orthogonal to the X axis direction.

  Further, as in the grinding device 1b shown in FIG. 4, the axis 41a of the advance / retreat shaft 41 may be located between the centroid 520a of the one column portion 520 and the chord 102a of the grinding region 102. Also in this case, the axis 40a of each of the two guides 40, the axis 41a of the advance / retreat axis 41, and the centroid 520a of the two column portions 520 are arranged on one reference straight line 202, Since the reference straight line 202 and the string 102a are parallel to each other, the rotation shaft 300 of the grinding spindle 30 is not easily inclined, and abnormal wear or grinding failure of the grinding wheel 320 can be prevented.

  In addition, in the example shown in FIGS. 1-4, the pillar part is formed in L shape, However, The cross-sectional shape of a pillar part may be other than L shape.

  The same applies to a grinding apparatus provided with a plurality of grinding means and grinding feed means. For each grinding means and grinding feed means, at least the axis of each of the two guides and the axis of the advance / retreat axis are 1 If it is arranged on the reference straight line of the book and the string of the grinding area is parallel to the reference straight line, the rotation axis of the grinding spindle is difficult to tilt, and it is possible to prevent abnormal grinding of the grinding wheel and poor grinding. . In the grinding apparatus provided with a plurality of grinding means and grinding feed means, a plurality of holding tables are supported by the turntable, and each holding table moves to a position facing the grinding wheel by rotation of the turntable. The turntable functions as positioning means.

1: Grinding device 2: Holding table 20: Positioning means 21: Cover member 2a: Holding surface 3: Grinding means 30: Grinding spindle 300: Rotating shaft 300a: Center axis 31: Spindle holder 32 Grinding wheel 320: Grinding wheel 4: Grinding Feed means 40: Guide 40a: Axis center 41: Advancing / retracting axis 41a: Center axis 42, 52: Portal column 420, 520: Column part 420a, 520a: Centroid 421: Connecting part 100: Grinding area 100a: String in grinding area 101: Grinding region 101a: Grinding region chord 102: Grinding region 102a: Grinding region chord 200, 201, 202: Reference straight line

Claims (4)

A rotatable holding table for holding a plate-like work, a grinding means for grinding the plate-like work held on the holding table, and a forward and backward movement in a grinding feed direction for moving the grinding means toward or away from the holding table Grinding feed means, and positioning means for positioning the plate-like workpiece held by the holding table relatively to a position facing a grinding wheel arranged in an annular manner on a grinding wheel mounted on the grinding means, In a grinding apparatus for in-feed grinding the upper surface of the plate-like workpiece held by the holding table by the grinding means,
The grinding means is composed of a grinding spindle having a rotating shaft on which a grinding wheel is mounted, and a spindle holder that supports the grinding spindle,
The grinding feed means is arranged in parallel to the grinding feed direction, guides the vertical movement of the spindle holder, and advances and retracts the spindle holder directed by the two guides in the grinding feed direction. It consists of advancing and retracting axes,
The axis of each of the two guides and the axis of the advance / retreat axis are arranged on one reference line, the reference line, the upper surface of the plate-like workpiece held by the holding table, and the grinding A grinding apparatus in which chords of a grinding region connecting a starting point and an ending point of an arc-shaped grinding region in contact with a grindstone are arranged in parallel. A portal column having the two guides and an advancing / retracting shaft for grinding and feeding the grinding means;
The portal-type column is composed of two column portions that respectively support the two guides, and a connecting portion that connects the two column portions.
The grinding apparatus according to claim 1, wherein a centroid of a column section cross section of the column section is disposed on the reference straight line.   2. The grinding apparatus according to claim 1, wherein a midpoint of a chord of the grinding region forming an arc shape coincides with an axis of the advance / retreat axis.   The positioning means moves the grinding means in the Y-axis direction, which is a direction in which the grinding means approaches and separates from the holding means, and moves the holding means in the X-axis direction orthogonal to the Y-moving means. The grinding apparatus according to claim 1, comprising X moving means.

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