JP2015036170A - Grinding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding device which enables a user to easily recognize damage and the residual quantity of grindstones and prevents processing failure of a plate-like workpiece.SOLUTION: A grinding device 1 includes: a holding table 3 which holds a plate-like workpiece W; grinding means 4 to which a grinding wheel 4f formed by annularly arranging grindstones 4d for griding the plate-like workpiece is attached; a drive motor which rotates the grinding wheel; a measuring apparatus; and a recognition part. The measuring apparatus includes: a light projection part which projects measurement light B; and a light receiving part which receives the measurement light B reflected on grinding surfaces 4e of the grindstones. The recognition part measures the rotating grinding surfaces with the measuring apparatus and enables a user to recognize the residual quantity and the existence of damage.

Description

  The present invention relates to a grinding apparatus for grinding a plate-shaped workpiece, and more particularly to a grinding apparatus capable of grinding a plate-shaped workpiece with a grinding wheel of a grinding means.

  2. Description of the Related Art Conventionally, as a plate workpiece processing apparatus, a grinding device that thins a plate workpiece to a target finish thickness is known (see, for example, Patent Document 1). The grinding apparatus described in Patent Literature 1 includes a holding table that holds a plate-like workpiece with a holding surface, and a grinding unit that includes a grinding wheel that grinds the plate-like workpiece with a grinding surface. In the grinding means, a grinding wheel is disposed on a wheel base, and the wheel base is attached to a wheel mount.

  By the way, in the grinding apparatus, a type capable of recognizing the remaining amount and wear amount of the grinding wheel is known, and as a recognition method there is a method described below. First, before grinding, the height position of the grinding means with which the grinding surface comes into contact with the holding surface of the holding table is recognized as the origin position. During grinding, the height position of the surface to be ground of the plate-like workpiece with respect to the holding surface is measured via a probe or the like, while the grinding means is moved toward and away from the holding table with respect to the origin position via a drive motor or the like. Measure the height position of the grinding means. Then, the remaining amount of the grinding wheel can be calculated and recognized from the height position of the plate-like workpiece with respect to the measured origin position and the height position of the grinding means.

JP 2008-73785 A

  However, in the above-described method, even if the grinding wheel is partially damaged or the grinding wheel is clogged, the height position of the plate-like workpiece and the grinding means to be measured does not change. For this reason, there is a problem of causing processing defects such as unevenness in the grinding pattern formed on the ground plate-like workpiece. In order to solve such a problem, it is conceivable that the operator periodically confirms the grinding wheel visually, but there is a problem that it is inefficient and requires a lot of labor for the operator.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a grinding apparatus that can easily recognize the breakage and remaining amount of a grinding wheel and prevent processing defects of a plate-like workpiece. And

  The grinding apparatus of the present invention comprises a holding table for holding a plate-like workpiece, a grinding means for mounting a grinding wheel for annularly arranging a grinding wheel for grinding the plate-like workpiece held by the holding table, and rotating the grinding wheel In a grinding apparatus comprising: a rotating means for moving; and a grinding feed means for moving the grinding means in a direction approaching and separating from the holding table, a light projection for projecting measurement light onto the grinding surface of the grinding wheel And a measuring device provided with a light receiving unit that receives the measurement light that is projected from the light projecting unit and reflected by the grinding surface, and is rotated at a predetermined number of rotations by the rotating means. The grinding surface of the grinding wheel is measured by the measuring device, and a recognition unit for recognizing the remaining amount of the grinding wheel and the presence or absence of breakage is provided.

  According to this configuration, the shape of the grinding surface in the grinding wheel can be detected by projecting the measurement light onto the grinding surface of the grinding means and receiving the reflected light reflected. Thereby, partial breakage and abnormal wear of the grinding wheel can be detected, and it becomes possible to prevent processing defects such as uneven grinding patterns formed on the ground plate-like workpiece. Further, by detecting the remaining amount of the grinding wheel, it is possible to accurately tell the operator when to replace the grinding wheel.

  Further, the grinding device of the present invention includes a frame body surrounding the measuring device, a measurement port formed in the frame body and allowing measurement by light projection and reception of the measuring device, and storing water inside the frame body. A water layer forming part that is formed so as to allow the water to flow out from the measurement port while covering the light projecting unit and the light receiving unit with water, and a supply port for supplying water to the water layer forming unit, It has. In this configuration, the light projecting unit and the light receiving unit are covered with water, and the water supplied from the supply port flows out of the measurement port, so that dirt can be prevented from adhering to the light projecting unit and the light receiving unit, and the measurement accuracy can be improved. It becomes possible to make it more stable.

  According to the present invention, it is possible to easily recognize the breakage and remaining amount of the grinding wheel, and to prevent the processing failure of the plate workpiece.

1 is a perspective view showing an example of a grinding apparatus according to Embodiment 1. FIG. It is a cross-sectional schematic diagram of the grinding apparatus. It is a schematic perspective view of the measurement means which the said grinding device has. It is a cross-sectional schematic diagram of the measuring means. It is a graph which shows the measurement result of the said measuring means. 5 is a schematic cross-sectional view of a grinding apparatus according to Embodiment 2. FIG.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 is a perspective view showing an example of a grinding apparatus according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the grinding apparatus according to the first embodiment.

  As shown in FIGS. 1 and 2, the grinding apparatus 1 is configured to grind the plate-like workpiece W held by the holding table 3 by relatively rotating the holding table 3 and the grinding means 4. A measuring means 5 is provided in the right area of the holding table 3. A detection means 11 is provided in the left area of the holding table 3.

As the plate-like workpiece W that is a workpiece in the grinding apparatus 1, a silicon wafer or a substrate made of a hard difficult-to-grind material can be employed. Such a plate-like workpiece W is made of, for example, a material such as sapphire, silicon carbide (SiC), Altic (AlTiC), or alumina ceramic (Al ₂ O ₃ ) having a Vickers hardness of 2000 or more.

  The grinding apparatus 1 has a base 2 having a substantially rectangular parallelepiped shape. A rectangular opening 21 extending in the X-axis direction and a column 22 provided vertically behind the opening 21 are arranged on the upper surface of the base 2. The opening 21 is covered with a table support 24 that supports the holding table 3 and a bellows-shaped dust-proof cover 25. The column 22 has a rectangular parallelepiped shape, and the grinding means 4 is provided on the front surface thereof.

  The table support 24 has a substantially square shape and supports the holding table 3. The table support 24 is connected to a driving mechanism (not shown), and slides in the X-axis direction within the opening 21 by a driving force supplied from the driving mechanism. As a result, the holding table 3 supplies the plate-shaped workpiece W before processing, and a replacement position for collecting the plate-shaped workpiece W after processing, and a grinding position where the grinding means 4 and the plate-shaped workpiece W face each other. Slide between the two.

  The dust-proof cover 25 prevents grinding dust generated during grinding of the plate-like workpiece W from entering the base 2. The dust cover 25 is attached to the front surface and the rear surface of the table support base 24, and is provided so as to be expandable and contractable according to the movement position.

  The holding table 3 has a disk shape and is provided so as to be rotatable about a disk center by a chuck rotating means (not shown). On the upper surface of the holding table 3, a holding surface 3 a that sucks and holds the plate-like workpiece W is provided. The holding surface 3a is made of, for example, a porous ceramic material, and the horus ceramic material is connected to a suction source (not shown).

  In the grinding means 4, a wheel mount 4b is provided at the lower end of a cylindrical spindle 4a, and a grinding wheel 4f is attached to the lower surface of the wheel mount 4b. The grinding wheel 4f is configured by arranging a plurality of grinding wheels 4d in an annular shape on the lower surface of the wheel base 4c. The grinding wheel 4d is composed of, for example, a vitrified bond wheel. The grinding wheel 4d rotates at high speed around the Z axis as the spindle 4a is driven, and the lower surface becomes the grinding surface 4e to contact the plate-like workpiece W for grinding. The spindle 4a is fixed to the output shaft of the drive motor 8 serving as a rotating means. Therefore, the grinding wheel 4 f is rotated via the spindle 4 a by the drive of the drive motor 8.

  The grinding means 4 is driven by a grinding feed means 44 provided in the column 22 and is configured to be movable in the vertical direction (Z-axis direction), and relatively moves the grinding means 4 and the holding table 3 closer to and away from each other. Is possible. The grinding feed means 44 has a Z-axis table 44a, and the grinding means 4 is supported via a support portion 44b attached to the front side of the Z-axis table 44a. A nut portion (not shown) protruding rearward is provided on the back surface of the Z-axis table 44a. A ball screw 44c provided on the front surface of the column 22 is screwed into the nut portion of the Z-axis table 44a. And the grinding means 4 is moved to an up-down direction (Z-axis direction) by the servomotor 44d connected with the one end part of the ball screw 44c being rotationally driven. The servo motor 44d is provided with a rotary encoder 44e as a detection unit for detecting the number of rotations (pulse number), and the grinding means 4 is controlled by a pulse signal output from the rotary encoder 44e for detecting the number of rotations of the servo motor 44d. The amount of movement is calculated.

  The measuring means 5 includes a measuring device 51 (see FIG. 3) provided on the upper surface side of the base 2 and on the right side of the holding table 3 in FIG. As shown in FIGS. 3 and 4, the measuring instrument 51 includes a light projecting unit 51 a and a light receiving unit 51 b and is surrounded by a frame body 52. The light projecting unit 51a projects the measurement light B, which is a laser beam, toward the grinding surface 4e positioned above through the measurement port 52a formed in the upper part of the frame body 52. The light receiving unit 51b receives the measurement light B reflected by the grinding surface 4e and passing through the measurement port 52a. The light receiving unit 51b includes a CCD, and measures the position of the grinding surface 4e in the Z-axis direction according to the position of the measurement light B received by the CCD. Then, the recognition unit 7 connected to the measuring means 5 recognizes the remaining amount of the grinding wheel 4d and the presence or absence of breakage from the change in the position of the grinding surface 4e according to the rotation angle of the rotating grinding wheel 4d.

  The measurement port 52a of the frame 52 is formed so as to penetrate in the vertical direction, and is provided so as to allow measurement by the light projection and reception of the measuring device 51. A space inside the frame 52 and between the upper surface of the measuring instrument 51 and the measurement port 52a is formed as a water layer forming part 52b. A supply port 52c communicating with the water layer forming portion 52b is formed on the side surface of the frame 52, and a water supply source (not shown) is connected to the supply port 52c, and 0.5 to 1 is connected to the water layer forming portion 52b. Water is supplied at a flow rate of 0.0 L / min. The water supplied to the water layer forming part 52b flows out of the measurement port 52a and is collected through the collecting means (not shown) together with the grinding water used in the grinding means 4. Accordingly, in the water layer forming part 52b, the water flow from the supply port 52c to the measurement port 52a is always maintained, and the light projecting unit 51a and the light receiving unit 51b of the measuring instrument 51 are covered with water, and grinding is performed from the measurement port 52c. Suppresses the entry of debris.

  The detecting means 11 includes a support portion 11a provided vertically on the base 2 and two measurement probes 11b and 11c provided on the upper portion of the support portion 11a. The detecting means 11 brings one probe 11b into contact with the upper surface of the plate-like workpiece W held on the chuck table 3, and the other probe 11c comes into contact with the holding surface 3a of the holding table 3 so that each probe 11b, The height position of 11c is measured. And the thickness of the plate-shaped workpiece | work W is recognized by taking the difference of the height position of the probes 11b and 11c.

  In the base 2, a control unit 6 that controls each part of the grinding device 1 is provided. The control unit 6 includes a processor that executes various processes, and a storage medium such as a ROM (Read Only Memory) and a RAM (Random Access Memory). For example, the control unit 6 controls a process of displaying the replacement time of the grinding wheel 4f on a display device (not shown) according to the remaining amount of the grinding wheel 4d recognized by the recognition unit 7 and the presence or absence of damage.

  Next, a grinding method using the grinding apparatus 1 of the present embodiment will be described. First, after the plate-like workpiece W is sucked and held by the holding surface 3a of the holding table 3, the table support 24 is driven to move the holding table 3 in the X-axis direction, and the plate-like workpiece W faces the grinding wheel 4d. Position at the grinding position.

  Subsequently, by driving the servo motor 44 d of the grinding feed means 44, the grinding means 4 descends at a high speed and approaches the plate-like workpiece W on the holding table 3. Then, the number of pulses of the rotary encoder 44e arranged in the servo motor 44d is counted, and when it is detected that the grinding means 4 has approached a predetermined distance from the grinding start position, the grinding wheel 4d is rotated and ground. The descending speed of the means 4 is set to a low speed. When the grinding means 4 descends and the grinding wheel 4d reaches the surface of the plate-like workpiece W, grinding is started. During the grinding process, the thickness of the plate-like workpiece W is measured in real time by the detection means 11. The feed amount of the grinding means 4 by the servo motor 44d is controlled so that the measurement result approaches the target finish thickness, and the plate-like workpiece W is ground to the finish thickness.

By the way, conventionally, the wear amount of the grinding wheel is recognized by the difference between the thickness of the plate-shaped workpiece before being ground by the detecting means and the thickness of the plate-shaped workpiece after being ground. And recognizing the feed amount of the grinding means from the pulse signal detected from the rotary encoder 44e,
[Feeding amount of grinding means]-[Grinding amount of grinding plate-like workpiece] = [Abrasion amount of grinding wheel]
It is calculated as

  Returning to the description of the present embodiment, during grinding of the plate-like workpiece W, the grinding surface 4e of the grinding wheel 4d on the rotating grinding wheel 4f is measured by the measuring device 51. As shown in FIG. 2, during grinding of the plate-like workpiece W, a part of the grinding wheel 4 d (in this embodiment, the right side area in FIG. 2) protrudes from the holding table 3. Measuring light B is projected from the light receiving portion 51a of the measuring device 51 onto the grinding surface 4e of the grinding wheel 4d. Then, since the grinding wheel 4f rotates at a predetermined rotational speed, the position of the grinding surface 4e on which the measurement light B is incident is also displaced in the rotational direction. Accordingly, the measurement light B reflected by the grinding surface 4e is received by the light receiving portion 51b, the position of the grinding surface 4e in the Z-axis direction is measured in real time, and the waveform processing (see FIG. 5) is performed, thereby forming the shape of the grinding surface 4e. Can be detected.

  FIG. 5 is a graph of the measurement results obtained by the measuring means 5, and FIG. 5B is an enlarged view of a part in the horizontal axis direction of FIG. 5A. In FIG. 5, the vertical axis represents the height in the Z-axis direction of the grinding wheel 4d (the amount of protrusion of the grinding wheel 4d from the lower surface of the wheel base 4c), and the horizontal axis represents the rotation angle of the grinding wheel 4f. In FIG. 5B, the Z-axis height of the grinding wheel 4d is reduced at intervals of about 20 ° in the horizontal axis direction. This is because a plurality of grinding wheels 4d are arranged side by side in an annular manner. This indicates that there is a gap between the two. Therefore, the portion indicated by reference numeral d1 between the two gaps in FIG. 5B indicates the width of the grinding wheel 4d, and the shape of the grinding wheel 4d is detected at this portion.

  As shown in FIG. 5B, the height of the grinding surface 4e of each grinding wheel 4d changes by repeating a plurality of increases and decreases within a predetermined angle range. In the recognition unit 7, the mode h1 of the height of the grinding surface 4e is calculated within a range of 360 ° corresponding to one rotation of the grinding wheel 4f. When 80% of the measurement data is in the set area h2 that is increased or decreased by a predetermined height with respect to the mode h1, the recognition unit 7 recognizes that the grinding wheel 4d is in a normal state in which grinding can be performed normally. When the measurement data existing in the setting area h2 is less than 80% and there are many values close to the mode h1, that is, when the increase / decrease in the grinding surface 4e is small, the grinding wheel 4d is clogged with grinding debris etc. The state is recognized by the recognition unit 7 as a state. Further, when there are many values where the measurement data existing in the setting area h2 is less than 80% and exceeds the setting area h2, that is, when the increase or decrease of the grinding surface 4e is large, an abnormality that causes abnormal wear or breakage of the grinding wheel 4d. The state is recognized by the recognition unit 7 as a state. Furthermore, as shown by a dotted line in FIG. 5B, when only a part of the plurality of grinding wheels 4d has an extremely low grinding surface 4e, the recognition unit 7 recognizes that the grinding wheel 4d is damaged. The Based on the recognition unit 7 recognizing the abnormal state described above, the control unit 6 controls the operation of the grinding means 4 and the like, interrupts the grinding, and operates a display device and a notification device (both not shown). The above-mentioned abnormality is transmitted to the operator.

  Moreover, in the recognition part 7, the height of the grinding surface 4e used as the mode h1 is recognized as the residual amount of the grinding wheel 4d. Based on the recognition unit 7 recognizing that the mode value h1 is smaller than the predetermined value, the control unit 6 operates a display device and a notification device (both not shown) to replace the grinding wheel 4f to the operator. Can be conveyed accurately.

  As described above, according to the grinding apparatus 1 according to the present embodiment, the rotating grinding surface 4e can be recognized as a surface shape, and compared with a case where a plurality of locations on a stationary grinding surface are detected. 4d breakage and abnormal wear can be detected more accurately. As a result, processing defects such as uneven grinding patterns formed on the ground plate-like workpiece W can be prevented, and the quality can be stabilized and the product accuracy can be improved.

(Embodiment 2)
The second embodiment will be described below. Note that, in the second embodiment, the same reference numerals are given to components common to the first embodiment, and description thereof is omitted. FIG. 6 is a schematic sectional view of a grinding apparatus according to the second embodiment. As shown in FIG. 6, in the grinding means 4 of the second embodiment, the diameter dimension of the grinding wheel 4f is set to about half the diameter dimension of the plate-like workpiece W. In such grinding by the grinding means 4, the annular convex portion W1 is formed without grinding only the predetermined width region along the outer edge of the plate-like workpiece W, and only the central portion of the plate-like workpiece W is thinned.

  A holding table moving mechanism 9 is provided between the base 2 and the holding table 3. The holding table moving mechanism 9 includes a guide rail 91 disposed on the base 2 and extending in the Y-axis direction, a Y-axis table 92 slidably installed on the guide rail 91, and the Y-axis table 92 as a guide rail 91. The moving means (not shown) which consists of a ball screw, a nut, and a motor for moving along. A measuring means 5 is provided on the upper surface of the Y-axis table 92 and on the side of the holding table 3.

  The grinding of the plate-like workpiece W in the present embodiment is performed at a position where the grinding surface 4e of the grinding means 4 does not protrude from the outer periphery of the plate-like workpiece W and falls within the plane of the plate-like workpiece W, as shown in FIG. 6A. Done. Then, as shown in FIG. 6B, before or after grinding the plate-like workpiece W, the grinding means 4 is raised by driving a servo motor 44d (not shown in FIG. 6B). After the grinding means 4 is raised, the Y-axis table 92 is moved in the Y-axis direction, and the measuring means 5 is positioned at a position directly below the grinding surface 4e of the grinding wheel 4d. In this state, the measurement light B is emitted from the light projecting portion 51a (not shown in FIG. 6B) of the measuring means 5 while rotating the grinding wheel 4f at a predetermined rotational speed by driving the drive motor 8 (not shown in FIG. 6B). Flood light. The rotation speed of the grinding wheel 4f at this time is not limited to the same rotation speed at the time of grinding, and can be adjusted to be reduced or the like. The measurement light B is reflected by the grinding surface 4e and then received by the light receiving unit 51b (not shown in FIG. 6B) and processed in the same manner as in the first embodiment.

  Therefore, according to this embodiment, since the rotation speed of the grinding wheel 4f when measuring the grinding surface 4e can be adjusted, the measurement of the grinding surface 4e can be improved by setting the rotation speed suitable for the measuring instrument 51. It becomes possible to carry out stably with accuracy.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  Further, the number of the measuring means 5 installed is not limited to one, and may be plural. At this time, the measurable range of the grinding surface 4e can be expanded by arranging the measuring means 5 in the radial direction of the grinding wheel 4f.

  As described above, the present invention is useful for a grinding apparatus that grinds a plate-shaped workpiece with a grinding wheel mounted on a rotating grinding wheel.

DESCRIPTION OF SYMBOLS 1 Grinding device 3 Holding table 4 Grinding means 4d Grinding wheel 4e Grinding surface 4f Grinding wheel 7 Recognition part 8 Drive motor (rotating means)
44 Grinding feed means 51 Measuring instrument 51a Light emitting part 51b Light receiving part 52 Frame 52a Measuring port 52b Water layer forming part 52c Supply port B Measuring light W Plate workpiece

Claims (2)

A holding table for holding a plate-like work, a grinding means for mounting a grinding wheel for annularly arranging a grinding wheel for grinding the plate-like work held by the holding table, a rotating means for rotating the grinding wheel, and the holding A grinding apparatus comprising: a grinding feed means for moving the grinding means in a direction approaching and separating from the table;
A measuring instrument comprising: a light projecting unit that projects measurement light onto the grinding surface of the grinding wheel; and a light receiving unit that receives the measurement light that is projected from the light projecting unit and reflected by the grinding surface Including and
A grinding apparatus provided with a recognition unit for measuring the grinding surface of the grinding wheel rotated at a predetermined number of revolutions by the rotating means with the measuring device and recognizing the remaining amount of the grinding wheel and the presence or absence of damage.   A frame that surrounds the measuring device, a measurement port that is formed in the frame and allows measurement by light projection and reception of the measuring device, and is formed so that water can be stored inside the frame, and the light projecting unit And a water layer forming unit that allows the water to flow out from the measurement port while covering the light receiving unit with water, and a supply port that supplies water to the water layer forming unit. Grinding equipment.

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