Processing device and processing method

Abstract

To provide a processing device and a processing method which can improve processing accuracy in grinding processing or polishing processing which causes oscillation.SOLUTION: A processing device according to the present invention, which grinds or polishes a work-piece to be processed, comprises: a first rotating body that rotates a processing tool while holding the tool; a second rotating body that rotates a work-piece while holding the work-piece; a first driving part that makes at least either of the processing tool and the work-piece approach relatively in a direction of rotary shafts of the first and second rotating bodies; a second driving part that makes the at least either of the first and second rotating bodies oscillate in a direction perpendicular to the rotary shafts; and a control part that controls a distance between the rotary shafts of the first and second rotating bodies oscillated by the second driving part and processing pressure to the work-piece from the processing tool by the first driving part, where the second driving part has a mechanism that converts in direct proportion to the oscillation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a processing apparatus and a processing method for grinding or polishing an object. [Background technology]

[0002] For example, in the manufacture of semiconductor devices, the back surface of a semiconductor substrate (hereinafter also referred to as workpiece) is ground to thin it using a grinding device. Conventionally proposed grinding devices generally include a base, a workpiece spindle that is rotationally driven by a motor attached to the base, a headstock that is supported so as to be movable up and down relative to the base, and a tool spindle that is attached to the headstock and rotationally driven by the motor, and the workpiece to be ground is held by suction on the workpiece spindle, and the workpiece is ground using a grinding wheel attached to the tool spindle.

[0003] Some conventional grinding machines are equipped with a vibration imparting mechanism that imparts vibration to a rotating spindle holding a tool or workpiece in a direction perpendicular to the spindle rotation axis. This vibration imparting mechanism is characterized by comprising a dual shaft: a hollow cylindrical shaft rotatably supported on the base of the processing machine, and a spindle that extends through the hollow part of the shaft and integrally connects a collar rotatably supported on one end of the shaft and a spindle holder rotatably supported on the other end, and both end portions of the shaft that support the collar and spindle holder are formed as eccentric shaft portions that are eccentric by the same amount in approximately the same direction from the center of rotation of the shaft, and by rotating the vibration shaft and spindle, vibration is imparted to the tool or workpiece fixed to the collar in a direction perpendicular to the rotation axis as the collar rotates. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-131737 A DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0005] As described above, some conventional processing equipment performs an oscillating motion in a direction perpendicular to the direction of relative motion between the grinding wheel and the workpiece during grinding. However, as workpiece grinding and polishing processes become more precise, even more precise control of the oscillating motion is required.

[0006] The present invention has been made to solve the above-mentioned problems, and has an object to provide a processing apparatus and a processing method that can improve the processing accuracy of grinding or polishing processing that involves a swinging motion. [Means for solving the problem]

[0007] In order to solve the above problems, the processing device of the present invention is a processing device that grinds or polishes a workpiece to be processed, and includes a first rotating body that holds and rotates a processing tool, a second rotating body that holds and rotates the workpiece, a first drive unit that moves at least one of the processing tool and the workpiece relatively closer in the direction of the rotation axis of the first and second rotating bodies, a second drive unit that oscillates at least one of the first and second rotating bodies in a direction perpendicular to the rotation axis, and a control unit that controls the distance between the rotation axes of the first and second rotating bodies by the second drive unit and the processing pressure of the processing tool on the workpiece by the first drive unit, and is characterized in that the second drive unit has a linear drive mechanism that converts in direct proportion to the oscillating movement.

[0008] According to the above configuration, the change in the distance between the rotation axes of the first and second rotating bodies caused by the second drive unit, in other words, the rocking motion caused by the second drive unit, is converted into a rocking motion in direct proportion, thereby improving the controllability of the rocking motion based on the rotational motion.

[0009] In addition, the linear drive mechanism of the second drive unit of the processing device according to the present invention is characterized by having a screw and a ball screw that linearly move at least one of the first and second rotating bodies in the vertical direction, and a motor that rotates the screw about its axis.

[0010] According to the above configuration, the rotational motion of the motor can be converted into a swinging motion with high precision by the screw and ball screw.

[0011] In addition, the linear drive mechanism of the second drive unit of the processing device according to the present invention is characterized by having a rack gear and a pinion gear that mesh with each other to linearly move at least one of the first and second rotating bodies in the vertical direction, and a motor that rotates the pinion gear.

[0012] According to the above configuration, the rotational motion of the motor can be transmitted from the pinion gear to the rack gear and converted into a swinging motion with high precision.

[0013] Furthermore, the processing method of the present invention is a processing method for grinding or polishing a workpiece to be processed, and is characterized by having: a first processing step in which a first driving unit presses a processing tool rotated by a first rotating body against the workpiece rotated by a second rotating body to grind or polish a first region of the workpiece; a release step in which, after the first processing step, the processing tool is released from pressing against the workpiece; a movement step in which, after the release step, a second driving unit moves at least one of the first and second rotating bodies a predetermined amount in a direction perpendicular to the rotation axis; and a second processing step in which, after the movement step, the first driving unit presses the processing tool rotated by the first rotating body against the workpiece rotated by the second rotating body to grind or polish a second region of the processing surface of the workpiece.

[0014] According to the above configuration, the first region of the workpiece and the second region of the workpiece are processed in stages by using the second drive unit to change the distance between the rotation axes of the first and second rotors, in other words, by using the swinging motion of the second drive unit. As a result, highly accurate processing can be performed by taking into consideration the balance between the processing area and peripheral speed in the first and second regions and the processing pressure of the processing tool.

[0015] Furthermore, in the moving step of the processing method according to the present invention, the second drive unit is characterized in that it moves at least one of the first and second rotating bodies in the vertical direction by converting the swinging motion in direct proportion to the swinging motion.

[0016] According to the above configuration, the change in the distance between the rotation axes of the first and second rotating bodies caused by the second drive unit, in other words, the rocking motion caused by the second drive unit, is converted into a rocking motion in direct proportion, thereby improving the controllability of the rocking motion based on the rotational motion.

[0017] In addition, in the processing method according to the present invention, the first region is further distal to the rotation axis of the workpiece than the second region.

[0018] According to the above configuration, the contact area (processing area) between the first region, which is distal to the rotation axis of the workpiece, and the processing tool is larger than the contact area (processing area) between the second region, which is proximal to the rotation axis of the workpiece. Meanwhile, the processing pressure of the processing tool per unit area is higher in the second region than in the first region. Therefore, high-precision processing can be performed by taking into consideration the balance between the processing area and the processing pressure of the processing tool.

[0019] As described above, according to the present invention, it is possible to provide a processing apparatus and a processing method that can improve the processing accuracy of grinding or polishing processing that involves a swinging motion. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 2 is a configuration diagram (side view) of a processing apparatus according to an embodiment. [Figure 2] FIG. 2 is a functional configuration diagram of a control device according to the embodiment. [Figure 3] 10 is a flowchart showing a grinding process of the processing device according to the embodiment. [Figure 4] 10 is a flowchart showing a profile measurement process of the processing apparatus according to the embodiment. [Figure 5] 10A and 10B are explanatory diagrams of a swinging operation of the processing apparatus according to the embodiment. [Figure 6]FIG. 10 is a detailed explanatory view of the swinging operation (intermediate position) of the processing apparatus according to the embodiment. [Figure 7] 10A and 10B are detailed explanatory diagrams of the swinging operation (top dead center position) of the processing apparatus according to the embodiment. [Figure 8] 10A and 10B are detailed explanatory diagrams of the swinging operation (bottom dead center position) of the processing apparatus according to the embodiment. [Figure 9] FIG. 10 is a detailed explanatory view of the swinging operation of the processing apparatus according to the embodiment when it is moving forward (swinging forward); [Figure 10] FIG. 10 is a detailed explanatory view of the swinging operation of the processing apparatus according to the embodiment when it is retracted (swinging retraction). [Figure 11] 10 is a flowchart showing a multi-stage grinding process of the processing device according to the embodiment. [Figure 12] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 13] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 14] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 15] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 16] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 17] 1A to 1C are detailed explanatory diagrams of a specific example of a grinding process (multi-stage) according to an embodiment. [Figure 18] 10A and 10B are detailed explanatory diagrams of a specific example of a grinding process (cutting tool advancement type during oscillating reciprocation) according to an embodiment. [Figure 19] 10A and 10B are detailed explanatory diagrams of a specific example of a grinding process (cutting tool advancement type when swinging is stopped) according to an embodiment. [Figure 20] 10A and 10B are detailed explanatory diagrams of a specific example of a grinding process (cutting tool advancement type during forward swing movement) according to an embodiment. [Figure 21] 10A and 10B are detailed explanatory diagrams of a specific example of a grinding process (tool advancement type during swing retreat) according to an embodiment. [Figure 22] FIG. 10 is a configuration diagram (perspective view) of a processing apparatus according to another embodiment. [Figure 23]FIG. 10 is a configuration diagram (side view) of a processing apparatus according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, a grinding apparatus that grinds a workpiece will be mainly described as a processing apparatus, but the present invention can also be applied to a polishing apparatus (lapping apparatus).

[0022] (Embodiment) A processing apparatus and a processing method according to an embodiment of the present invention will be described with reference to the drawings. The processing apparatus 10 according to the embodiment is a grinding apparatus that grinds a workpiece W (e.g., a substrate mainly composed of silicon (Si), sapphire, silicon carbide (SiC), gallium nitride (GaN), etc.). The processing apparatus 10 is equipped with a plurality of detection sensors (61a-61d and 62a-62d) that detect the processing state, constantly collects the detection results of these detection sensors, and detects abnormalities in the processing apparatus 10 based on the detection results of these detection sensors. The processing apparatus 10 also has a function of dynamically changing a processing process (hereinafter also referred to as a recipe) that specifies the processing content for the workpiece W and is stored in the processing apparatus 10 based on the detection results of the detection sensors.

[0023] FIG. 1 is a side view of a processing apparatus 10 according to an embodiment. Note that FIG. 1 illustrates only the main components of the processing apparatus 10. As shown in FIG. 1, the processing apparatus 10 includes a base 20 (main frame), a workpiece holder 30 located on the lower side of the base 20, a tool rotation drive unit 40 located on the upper side of the base 20 opposite the workpiece holder 30, a swing mechanism 50 for swinging the tool rotation drive unit 40, and a control device 70. In addition to these components, the processing apparatus 10 may also include a profile measuring device 80. In this embodiment, the processing apparatus 10 including the profile measuring device 80 will be described as an example. Note that, although not shown in FIG. 1, a grinding fluid supply nozzle is provided for supplying grinding fluid to the workpiece W and grinding wheel G during processing by the processing apparatus 10.

[0024] The workpiece holding unit 30 includes a holding table 31 attached to the base 20, a motor 32 (preferably a servo motor), and a belt 33 (for example, a toothed belt, a V-belt, or the like) that transmits the power of the motor 32 to the holding table 31. The holding table 31 includes a spindle 311 that is rotated by the belt 33, a bearing 312 that is attached to the base 20 and rotatably holds the spindle 311, and a rotation stage 313 (second rotating body) that is attached to the upper end side of the spindle 311 and rotates together with the spindle 311.

[0025] The rotating stage 313 includes a porous plate made of a porous material such as ceramic, metal, silicon, organic polymer porous material, or resin, a frame that supports the porous plate, and a base to which the frame is attached. A suction path that communicates with the porous plate is formed in the frame and base of the rotating stage 313. This suction path communicates with a vacuum generation source (not shown), such as a vacuum pump and a vacuum generating ejector, and is configured to allow the workpiece W to be vacuum-chucked to the rotating stage 313 via the porous plate.

[0026] The tool rotation drive unit 40 includes a base 41 (frame), a tool spindle 42 (first rotor), a spindle cover 43, a guide rail (not shown) that guides the axial drive of the tool spindle 42 (drive in the Z direction indicated by the arrow α in the figure), a feed screw 45 that raises and lowers the tool spindle 42, a tool rotation drive motor 46 (preferably a servo motor), a belt 47 (e.g., a toothed belt, a V-belt, etc.) that transmits the power of the tool rotation drive motor 46 to the tool spindle 42, and an axial drive motor 48 (preferably a servo motor).The tool rotation drive unit 40 also includes a cylinder 49 that supports the weight of the unit that moves in the Z direction indicated by the arrow α in the figure.

[0027] The tool spindle 42 is rotated by a tool rotation drive motor 46 via a belt 47. A grinding wheel G, which is a grinding tool, is attached to the lower end of the tool spindle 42, facing the holding table 31 of the workpiece holding unit 30. The feed screw 45 is rotated by an axial drive motor 48, and raises and lowers the tool spindle 42 in the axial direction (the Z direction indicated by the arrow α in the figure) via a nut unit 421 with which the feed screw 45 is engaged.

[0028] The tool spindle 42 is suspended from an extendable cylinder 49 attached to the base 20. The cylinder 49 is a counterbalance cylinder that cancels the weight of units that move in the Z direction indicated by the arrow α in the figure, such as the tool spindle 42, spindle cover 43, tool rotation drive motor 46, and grinding wheel G, thereby reducing the load on the feed screw 45, nut unit 421, and axial drive motor 48. As shown in FIG. 1, the feed screw 45 and the cylinder 49 are disposed opposite each other across the tool spindle 42. Therefore, the tool spindle 42 is hardly subjected to a load in a diagonal direction (relative to the vertical direction), thereby extending the life of the feed screw 45, nut unit 421, guide rail (not shown), and the like.

[0029] Furthermore, the tool spindle 42 moves up and down along a guide rail (not shown) with almost no inclination at an angle relative to the vertical direction, and the processing load applied to the grinding wheel G when processing the workpiece W is transmitted straight to the workpiece W. Note that the cylinder 49 may be hydraulic, pneumatic, or of any other type as long as it can cancel out the weight of units that move in the Z direction indicated by arrow α in the figure, such as the tool spindle 42, spindle cover 43, tool rotation drive motor 46, and grinding wheel G.

[0030] The swing mechanism 50 includes a guide rail 51 for swinging the base 41, and a linear drive mechanism 55 connected at one end to the base 41 and swinging the base 41 left and right as viewed in the drawing (the X direction indicated by the arrow β in the figure). The linear drive mechanism 55 includes a screw 52, ​​a ball screw 521, and a motor 53 (preferably a servo motor) that rotates the screw 52. The linear drive mechanism 55 can convert the rotational motion of the motor 53 into the swinging motion of the base 41 in direct proportion. Note that the swinging motion may also be performed using a drive means that does not involve rotational motion, such as a linear motor.

[0031] The profile measuring instrument 80 is, for example, a laser measuring instrument, which measures and outputs the distance L between the profile measuring instrument 80 and the upper surface of the workpiece W. In the embodiment, the profile measuring instrument 80 is configured to measure the distance L to the upper surface of the workpiece W by scanning the workpiece W held on the rotating stage 313 (i.e., the profile measuring instrument 80 side operates), but if the grinding accuracy can be kept within the device specifications (specs), the profile measuring instrument 80 may be configured to scan the rotating stage 313 to measure the distance L to the upper surface of the workpiece W (i.e., the rotating stage 313 side operates).

[0032] The processing device 10 also includes a mechanical (contact) workpiece thickness measurement mechanism (not shown). This workpiece thickness measurement mechanism includes a first measurement unit that measures the height of the top surface of the workpiece W and a second measurement unit that measures the height of a reference surface (for example, the edge of the rotating stage 313 that holds the workpiece W by suction). The workpiece thickness measurement mechanism calculates and outputs the thickness of the workpiece W from the difference in height between the first measurement unit and the second measurement unit. The profile measuring device 80 can also serve as the workpiece thickness measurement mechanism. In most cases, the workpiece W is attached to a support substrate (by solvent welding or adhesive, for example) to prevent deformation or damage when attached to the rotating stage 313. The thickness of the workpiece W can be calculated from the difference in travel between the support substrate and the surface of the workpiece W. If the support substrate and the workpiece W have the same diameter, the difference in travel between the support substrate and the workpiece W can be determined from the defect caused by the oriental flat of the workpiece W. In this case, the profile measuring device 80 is moved slightly inward from the periphery of the determined diameter of the workpiece W, and the workpiece W is rotated to detect both ends of the concave portion of the orientation flat. The coordinates of the center of the orientation flat are calculated from the rotation coordinates of these two points on the rotary stage 313, clarifying the exposed portion of the support substrate due to the orientation flat, and thickness measurement is achieved by the travel difference at the same diameter. This allows the orientation flat position to be recorded in terms of the angular coordinates of the rotary stage 313, and allows the profile measuring device 80 to continuously measure thickness during subsequent processing (of the workpiece W whose coordinates have been determined when it is mounted on the rotary stage 313).

[0033] The control device 70 controls the processing device 10. The control device 70 is configured by an electronic circuit unit including a CPU, RAM, ROM, an interface circuit, etc. The control device 70 may also be configured by a plurality of electronic circuit units that can communicate with each other. FIG. 2 is a functional configuration diagram of the control device 70. The functions shown in FIG. 2 are realized by hardware such as a CPU, RAM, and ROM that the control device 70 has, and a program stored in a memory such as a ROM.

[0034] 2, the control device 70 includes a communication unit 71, a load monitor unit 72, a storage unit 73, a profile calculation unit 74, a control unit 75, etc. The communication unit 71 transmits a control signal for controlling a motor included in the processing device 10. The communication unit 71 also communicates with a server (not shown) to transmit and receive data, control signals, etc.

[0035] The load monitor unit 72 monitors the current values ​​(loads) output from the motors 32, 46, and 48. By monitoring the current values ​​output from the servo motors 32, 46, and 48, the loads on the motors 32, 46, and 48 can be monitored, and if a current value different from normal is detected, it can be determined that there is an abnormality, danger, or the like.

[0036] Specifically, the load monitor unit 72 is configured to determine a warning (an abnormality that can be fixed by resetting (changing) the recipe) when the monitored value (current value) falls outside a predetermined first range (first reference value range), and to determine an abnormality (an abnormality that cannot be fixed even by resetting (changing) the recipe) when the monitored value falls outside a second range (second reference value range) that is wider than the first range (first reference value range). The first and second ranges are set for each of the motors 32, 46, and 48, and are also set for each recipe that defines the grinding process procedure. The load monitor unit 72 may calculate the average deviation or moving average of the load (current value) of each of the motors 32, 46, and 48 within a predetermined time period (e.g., the most recent 2 seconds) and determine whether the average deviation or moving average falls outside the first and / or second range.

[0037] The memory unit 73 stores various recipes, which are procedures for grinding the workpiece W. In the recipes, various items are set, such as the rotation speed (rpm) and rotation direction of the workpiece W, the rotation speed and rotation direction of the grinding wheel, the grinding amount (target thickness of the workpiece W), the feed speed of the grinding wheel, the oscillation (reciprocating motion) speed during grinding, and the amount of grinding fluid discharged. In addition, the memory unit 73 sets first and second ranges for the motors 32, 46, and 48 for each recipe. Note that the first and second ranges for the motors 32, 46, and 48 may be set for each step of each recipe.

[0038] Furthermore, the memory unit 73 stores data that is referenced and used by the profile calculation unit 74 described later, such as position data of points at which the distance L from the top surface of the workpiece W is measured by controlling the profile measuring device 80 (e.g., multiple points on the peripheral edge of the workpiece W, multiple points inside, and the center), the distance L2 from the profile measuring device 80 to a reference surface (e.g., the edge of the rotating stage 313 that holds the workpiece W by suction), and correction data for correcting the thickness profile of the workpiece W.

[0039] Here, the correction data is acquired as follows: After a reference workpiece with a known thickness is sucked and held on the rotating stage 313, the distance L1 to the top surface of the reference workpiece is measured at the same position as the measurement point on the workpiece W. Next, the thickness of the workpiece W is calculated for each of the multiple measured points by subtracting the actually measured distance L1 to the top surface of the workpiece W from the distance L2 to a previously measured reference surface (for example, the edge of the rotating stage 313 that sucks and holds the workpiece W) stored in the memory unit 73, and a thickness profile of the reference workpiece is calculated. Next, the actual thickness is subtracted from the calculated thickness profile of the reference workpiece to create correction data. This correction data is used to correct errors in the distance L1 due to misalignment or tilt from the rotating stage 313 when the profile measuring instrument 80 scans the workpiece W.

[0040] The profile calculation unit 74 calculates the thickness distribution of the workpiece W (thickness profile). The operation of the profile calculation unit 74 (calculation of the thickness profile of the workpiece W by the profile calculation unit 74) will be described in detail with reference to FIG.

[0041] Control unit 75 controls processing apparatus 10 based on a procedure (recipe) stored in storage unit 73. The control of processing apparatus 10 by control unit 75 will be described in detail with reference to FIGS.

[0042] (Grinding process) FIG. 3 is a flowchart showing the grinding process of the processing device 10 according to the embodiment. In step S101, the control unit 75 refers to the selected recipe stored in the storage unit 73. In step S102, the control unit 75 controls the motors 32, 46, 48, 53, etc. in accordance with the procedure defined by the recipe to start the grinding process.

[0043] In step S103, the control unit 75 starts measuring the workpiece thickness. Specifically, the control unit 75 controls a mechanical (contact) workpiece thickness measuring mechanism (not shown) to obtain the thickness of the workpiece W output from the workpiece thickness measuring mechanism.

[0044] In step S104, the thickness distribution (profile) of the workpiece W during grinding is measured using the profile measuring device 80. In this profile measurement process, the feed rate of the grinding wheel G is corrected based on the actual grinding amount of the workpiece W. This profile measurement process will be described in detail with reference to FIG.

[0045] In step S105, the control unit 75 determines whether the thickness of the workpiece W output from the workpiece thickness measuring mechanism is the workpiece thickness (predetermined thickness) specified in the selected recipe. More specifically, the control unit 75 compares the thickness of the workpiece W output from the workpiece thickness measuring mechanism with the workpiece thickness (predetermined thickness) specified in the selected recipe, and determines whether the thickness of the workpiece W output from the workpiece thickness measuring mechanism is within a predetermined range (for example, within a 1% range of the workpiece thickness (predetermined thickness) specified in the selected recipe).

[0046] If, in step S105, the thickness of the workpiece W output from the workpiece thickness measuring mechanism is the workpiece thickness (predetermined thickness) specified in the selected recipe (YES), then in step S106, the control unit 75 controls the motors 32, 46, 48, 53, etc. in accordance with the procedure specified by the recipe to end the grinding operation, and then retracts the grinding wheel G to end the grinding process. Also, if, in step S105, the thickness of the workpiece W output from the workpiece thickness measuring mechanism is not the workpiece thickness (predetermined thickness) specified in the selected recipe (NO), the control unit 75 continues the grinding process until the thickness of the workpiece W output from the workpiece thickness measuring mechanism becomes the workpiece thickness (predetermined thickness) specified in the selected recipe.

[0047] (Profile measurement processing) Fig. 4 is a flowchart showing the profile measurement process of the processing device according to the embodiment. Note that this profile measurement process is performed during the grinding process described with reference to Fig. 3. For example, it is preferably performed when 50% to 80% of the set grinding amount has been completed. This is because if the grinding amount is less than 50% of the set grinding amount, the grinding amount is too small to derive the relationship between the feed rate of the grinding wheel G and the actual grinding amount of the workpiece W, and if it exceeds 80%, even if the feed rate of the grinding wheel G is corrected based on the actual grinding amount of the workpiece W, grinding may have progressed too far, making it impossible to correct the workpiece W.

[0048] In step S201, the profile of the workpiece W is measured by the profile measuring device 80. Specifically, the control unit 75 controls the profile measuring device 80 to measure the distance L1 between the top surface of the workpiece W and a plurality of preset points on the workpiece W (for example, a plurality of points on the peripheral edge of the workpiece W, a plurality of points inside the workpiece W, and the center, etc.).

[0049] In step S202, the profile calculation unit 74 subtracts the distance L1 measured in step S201 from the distance L2 to a previously measured reference surface (for example, the edge of the rotating stage 313 that holds the workpiece W by suction) stored in the memory unit 73 to calculate the thickness of the workpiece W for each of the multiple measured points, thereby calculating a thickness profile of the workpiece W.

[0050] In step S203, the profile calculation unit 74 corrects the thickness profile of the workpiece W calculated in step S202 using correction data stored in the memory unit 73, which was previously measured by suction-holding a reference workpiece on the rotating stage 313.

[0051] In step S204, the profile calculation unit 74 calculates the difference between the feed amount of the grinding wheel G by the feed screw 45 and the actual grinding amount of the workpiece W, based on the thickness profile of the workpiece W corrected in step S203. The control unit 75 corrects the feed amount of the grinding wheel G based on the difference calculated by the profile calculation unit 74. The control unit 75 executes the grinding process based on the corrected feed amount.

[0052] In addition, if the thickness profile of the workpiece W corrected in step S203 is convex (so-called mountain shape) with a thick center and thin peripheral edges, the motor 53 that performs the oscillating operation may be controlled so that the time (processing time) that the grinding wheel G takes to grind the area near the center position of the workpiece W is longer than the time (processing time) that it takes to grind other areas, or the torque of the axial drive motor 48 that feeds the feed screw 45 may be controlled so that the processing pressure when the grinding wheel G grinds the area near the center position of the workpiece W is higher.

[0053] Furthermore, if the thickness profile of the workpiece W corrected in step S203 is a concave shape (so-called valley shape) with a thin central portion and thick peripheral edges, the motor 53 that performs the oscillating operation may be controlled so that the time (processing time) for the grinding wheel G to grind the area near the central position of the workpiece W is shorter than the time (processing time) for grinding other areas, or the torque of the axial drive motor 48 that feeds the feed screw 45 may be controlled so that the processing pressure when the grinding wheel G grinds the area near the central position of the workpiece W is lower.

[0054] (swinging motion) FIG. 5 is an explanatory diagram of the swinging operation of the processing apparatus 10 according to the embodiment. The swinging operation will be described below with reference to FIG. 5. The same components as those described with reference to FIGS. 1 to 4 are designated by the same reference numerals, and redundant description will be omitted. As shown in FIG. 5(a), the control unit 75 of the control device 70 drives the tool rotation drive motor 46 to rotate the grinding wheel G attached to the lower end of the tool spindle 42. The control unit 75 of the control device 70 also drives the motor 32 to rotate the workpiece W held (vacuum chucked) on the rotary stage 313. In this embodiment, the grinding wheel G and the workpiece W each rotate counterclockwise (CCW). However, both the grinding wheel G and the workpiece W may rotate clockwise (CW), or the grinding wheel G may rotate clockwise (CW) and the workpiece W may rotate counterclockwise (CCW), or the grinding wheel G may rotate counterclockwise (CCW) and the workpiece W may rotate clockwise (CW).

[0055] 5(b), the control unit 75 of the control device 70 controls the axial drive motor 48 to rotate the feed screw 45 and lower the tool spindle 42 until the grinding wheel G comes into contact with the workpiece W. After the grinding wheel G and the workpiece W come into contact with each other, the control unit 75 controls the motor 53 to drive the screw 52 and the ball screw 521 to move the base 41 in the X direction while maintaining the rotation of the grinding wheel G and the workpiece W in a contacting state, thereby causing the grinding wheel G to oscillate (reciprocate laterally) on the surface of the workpiece W.

[0056] 6 to 8 are explanatory diagrams of the swinging operation of the processing device 10 according to the embodiment. The swinging operation will be described in more detail below with reference to Figs. 6 to 8, and the same components as those described with reference to Figs. 1 to 5 will be assigned the same reference numerals and redundant description will be omitted. In the embodiment, the top dead center position P1, bottom dead center position P2, and intermediate position P3 are defined as follows: (1)Top dead center position P1 6 to 8, this is the position where the direction of the swinging motion switches from left to right. More specifically, this is the position where the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 are closest to each other. Note that in a case where the swing width is large and the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 overlap and then separate (as explained with reference to FIGS. 6 to 8, the rotation axis C1 of the tool spindle 42 swings from right to left as viewed in the drawing, the rotation axis C1 of the tool spindle 42 overlaps with the rotation axis C2 of the spindle 311, and then the rotation axis C1 of the tool spindle 42 swings again from right to left as viewed in the drawing), the top dead center position P1 may be defined as the position where the grinding wheel G and the workpiece W overlap most in a plan view (a plane perpendicular to the Z axis) (the position where the overlapping area between the grinding wheel G and the workpiece W is widest in a plan view). (2) Bottom dead center position P2 6 to 8, bottom dead center position P2 is the position where the direction of the swinging motion switches from right to left. More specifically, it is the position where the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 are farthest apart. Note that in a case where the swing width is large and the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 overlap and then separate (as explained with reference to FIGS. 6 to 8, the rotation axis C1 of the tool spindle 42 swings from right to left as viewed in the drawing, the rotation axis C1 of the tool spindle 42 overlaps with the rotation axis C2 of the spindle 311, and then the rotation axis C1 of the tool spindle 42 swings again from right to left as viewed in the drawing), the position where the grinding wheel G and the workpiece W overlap least in a plan view (a plane perpendicular to the Z axis) (the position where the overlapping area between the grinding wheel G and the workpiece W is smallest in a plan view) may be defined as bottom dead center position P2. (3) Intermediate position P3 A position between the top dead center position P1 and the bottom dead center position P2.

[0057] Figure 6 is a detailed explanatory diagram of the swinging motion at intermediate position P3. Figure 6(a) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G, and Figure 6(b) is a front view showing the positional relationship between the workpiece W and the grinding wheel G. As shown in Figure 6, at intermediate position P3, the grinding wheel G is swinging and moving in the left-right direction in Figure 6 on the surface of the workpiece W. As a result, the processing pressure from the grinding wheel G is dispersed, and the stress acting on the surface of the workpiece W is also dispersed.

[0058] FIG. 7 is a detailed explanatory diagram of the oscillation operation at the top dead center position P1. FIG. 7(a) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G, and FIG. 7(b) is a front view showing the positional relationship between the workpiece W and the grinding wheel G. Because the top dead center position P1 is the stop position for the oscillation operation, as shown in FIG. 7, the grinding wheel G temporarily stops on the surface of the workpiece W at the top dead center position P1. As a result, the processing pressure from the grinding wheel G is not dispersed, and stress on the surface of the workpiece W is concentrated at the contact area with the grinding wheel G. As a result, vibrations may occur on the surface of the grinding wheel G and / or the workpiece W, deteriorating at least one of the flatness and surface roughness of the ground surface. Therefore, in the processing apparatus 10 according to the embodiment, the control unit 75 controls the torque (current value) of the axial drive motor 48 to reduce the grinding pressure at the top dead center position P1, thereby suppressing vibrations on the surface of the grinding wheel G and / or the workpiece W and suppressing deterioration of the flatness and surface roughness of the ground surface.

[0059] FIG. 8 is a detailed explanatory diagram of the oscillation operation at bottom dead center position P2. FIG. 8(a) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G, and FIG. 8(b) is a front view showing the positional relationship between the workpiece W and the grinding wheel G. As with top dead center position P1, bottom dead center position P2 is a stop position for the oscillation operation. Therefore, as shown in FIG. 8, the grinding wheel G temporarily stops on the surface of the workpiece W at bottom dead center position P2. As a result, the processing pressure from the grinding wheel G is not dispersed, and stress on the surface of the workpiece W is concentrated in the contact area with the grinding wheel G. As a result, vibrations may occur on the surface of the grinding wheel G and / or the workpiece W, deteriorating at least one of the flatness and surface roughness of the ground surface. Therefore, in the processing apparatus 10 according to the embodiment, the control unit 75 controls the torque (current value) of the axial drive motor 48 to reduce the grinding pressure at bottom dead center position P2, thereby suppressing vibrations on the surface of the grinding wheel G and / or the workpiece W and suppressing deterioration of the flatness and surface roughness of the ground surface.

[0060] 9 and 10 are detailed explanatory diagrams of the swinging operation of the processing device 10 according to the embodiment when it is moved forward (hereinafter also referred to as swinging forward) and when it is moved backward (hereinafter also referred to as swinging backward). The swinging operation when it is moved forward and when it is moved backward will be described in detail below with reference to FIGS. 9 and 10, and the same components as those described with reference to FIGS. 1 to 8 will be assigned the same reference numerals and redundant description will be omitted. In the embodiment, the swinging operation when it is moved forward and when it is moved backward will be defined as follows: (4) Swing forward This refers to the swinging motion of the grinding wheel G when it moves from the bottom dead center position P2 to the top dead center position P1. In other words, this refers to the swinging motion when the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 approach each other. (5) Swinging Retreat This refers to the swinging motion of the grinding wheel G when it moves from the top dead center position P1 to the bottom dead center position P2. In other words, this refers to the swinging motion when the rotation axis C1 of the tool spindle 42 and the rotation axis C2 of the spindle 311 move away from each other.

[0061] FIG. 9 is a detailed explanatory diagram of the swinging motion during swing forward movement. FIG. 9(a) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G, and FIG. 9(b) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G. As shown in FIG. 9, during swing forward movement, the component force vector of the forward thrust diffuses in the direction perpendicular to the outer periphery of the rotation of the grinding wheel G. Furthermore, the component force acts in a direction perpendicular to the outer periphery of the workpiece W, which may cause a peeling action on the workpiece W and chipping of the end of the workpiece W (potentially resulting in chipping). Therefore, in the processing apparatus 10 according to the embodiment, the control unit 75 controls the torque (current value) of the axial drive motor 48 to reduce the grinding pressure during swing forward movement, thereby preventing chipping of the workpiece W.

[0062] FIG. 10 is a detailed explanatory diagram of the swinging motion during swing retreat. FIG. 10(a) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G, and FIG. 10(b) is a plan view showing the positional relationship between the workpiece W and the grinding wheel G. As shown in FIG. 10, during swing retreat, the component force vectors of the retreating thrust converge in the direction perpendicular to the inner circumference of the rotation of the grinding wheel G. Furthermore, the component forces are not perpendicular to the outer peripheral edge of the workpiece W, but rather counterbalance each other at the outer peripheral edge of the workpiece W. As a result, the component force action at the outer peripheral edge of the workpiece W is reduced, reducing the risk of chipping at the end of the workpiece W (reducing the risk of chipping, etc.). Therefore, in the processing apparatus 10 according to this embodiment, the control unit 75 controls the torque (current value) of the axial drive motor 48 to increase the grinding pressure during swing retreat, thereby improving the grinding efficiency of the workpiece W. This improves the throughput of the processing apparatus 10.

[0063] In the above-described swinging operation, in this embodiment, the swinging mechanism 50 includes the screw 52 and ball screw 521 as the linear drive mechanism 55, and the motor 53 that rotates the screw 52. Therefore, the rotational movement of the motor 53 can be converted into swinging movement in direct proportion, and the amount of swing can be controlled with high precision by controlling the rotation of the motor 53. For example, by using a servo motor or a stepping motor as the motor 53, the amount of swinging and the swinging speed can be obtained at a constant ratio to the rotation angle and rotation speed of the motor 53. In other words, swinging can be accurately controlled by controlling the rotation of the motor 53, and processing precision can be improved.

[0064] Although the linear drive mechanism 55 of the swing mechanism 50 has been exemplified as including the screw 52, ​​the ball screw 521, and the motor 53, other configurations may also be used. For example, the linear drive mechanism 55 may include a rack gear and a pinion gear that mesh with each other to linearly move at least one of the tool spindle 42 and the spindle 311 in the X direction, and the motor 53 that rotates the pinion gear.

[0065] FIG. 11 is a flowchart showing the multi-stage grinding process of the processing apparatus 10 according to the embodiment. The multi-stage grinding process shown in Fig. 11 is executed during the start of the grinding process shown in step S102 of Fig. 3 .

[0066] In step S301, processing is performed on a first region on the processing surface of the workpiece W. That is, grinding is performed by rotating the grinding wheel G rotated by the tool spindle 42 using the spindle 311 and pressing it against the processing surface of the workpiece W. In this grinding process, the grinding wheel G grinds a first region, which is a portion of the processing surface of the workpiece W. To grind the first region, the linear drive mechanism 55 of the swing mechanism 50 controls the position of at least one of the tool spindle 42 and the spindle 311 in a direction perpendicular to the rotation axis (X direction) so that the grinding wheel G comes into contact with the first region of the workpiece W.

[0067] In step S302, the grinding wheel G is released from pressing against the workpiece W. After the grinding process of the first region by the grinding wheel G is completed, the axial direction drive motor 48 is controlled to move the grinding wheel G away from the processing surface of the workpiece W.

[0068] In step S303, a predetermined amount of movement is performed. That is, after the grinding wheel G is released from pressing against the workpiece W in step S302, the linear drive mechanism 55 of the swing mechanism 50 controls the position of at least one of the tool spindle 42 and the spindle 311 in the direction perpendicular to the rotation axis (X direction) so that the grinding wheel G is in a positional relationship that allows it to contact a second region of the workpiece W other than the first region.

[0069] In step S304, the second region is processed. With the grinding wheel G and the second region of the workpiece W positioned in step S303 so as to be in contact with each other, the grinding wheel G rotated by the tool spindle 42 is rotated by the spindle 311 and pressed against the processing surface of the workpiece W to perform grinding. In this grinding process, the second region of the processing surface of the workpiece W is ground by the grinding wheel G.

[0070] In step S305, the processing tool is released from pressing against the workpiece. After the grinding process of the second region by the grindstone G is completed, the axial direction drive motor 48 is controlled to move the grindstone G away from the processing surface of the workpiece W.

[0071] When multi-stage grinding is performed on three or more regions, the processes from step S303 to step S305 are repeated for the third or more regions after step S305.

[0072] In such a multi-stage grinding process, the linear drive mechanism 55 of the swing mechanism 50 is used to perform the processing of the first region of the workpiece W and the processing of the second region of the workpiece W in stages. As a result, highly accurate processing can be performed by taking into consideration the balance between the processing area and peripheral speed in the first and second regions and the processing pressure of the grinding wheel G.

[0073] (Multi-stage grinding process) 12 to 14 are explanatory diagrams of a specific example of a multi-stage grinding process. The swinging operation will be described in more detail below with reference to FIGS. 12 to 14. The same components as those described with reference to FIGS. 1 to 11 are designated by the same reference numerals, and redundant description will be omitted. In the embodiment, an example of multi-stage grinding will be described in which three regions, namely, an outer peripheral region A1, an intermediate region A2, and an axial core region A3, are ground in stages. One of the three or more regions is a first region, and one of the regions other than the first region is a second region. The first region is a region distal to the rotation axis C2 of the workpiece W than the second region. The following describes an example in which the relative positions of the grinding wheel G and the workpiece W in the direction perpendicular to the rotation axis (X direction) are set by moving the grinding wheel G.

[0074] 12(a) is a plan view showing the positional relationship between the workpiece W and the grindstone G, and FIGS. 12(b) to 12(d) are front views showing the sequential changes in the positional relationship between the workpiece W and the grindstone G. FIG. First, the outer peripheral region A1 of the processing surface of the workpiece W is ground (first-stage grinding). In this first-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50, so that the axis (rotation axis C2) of the workpiece W is positioned outside the outermost periphery of the grinding wheel G in a plan view, and the innermost periphery of the outer peripheral region A1 of the workpiece W coincides with the outermost periphery of the grinding wheel G (see FIGS. 12(a) and 12(b)). Next, as shown in FIG. 12(c), the grinding wheel G is advanced a predetermined distance along the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the outer peripheral region A1 of the workpiece W, not the intermediate region A2 (see FIG. 12) or the axis region A3 (see FIG. 14). As a result, only the outer peripheral region A1 of the workpiece W is ground. After grinding of the outer peripheral region A1 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 12(d).

[0075] Next, the intermediate region A2 of the processing surface of the workpiece W is ground (second-stage grinding). In this second-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50, so that the axis (rotation axis C2) of the workpiece W is positioned outside the outermost periphery of the grinding wheel G in a plan view, and the innermost periphery of the intermediate region A2 of the workpiece W coincides with the outermost periphery of the grinding wheel G (see FIGS. 13(a) and 13(b)). Next, as shown in FIG. 13(c), the grinding wheel G is advanced a predetermined distance along the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the intermediate region A2 of the workpiece W. Here, the outer periphery region A1 does not come into contact with the grinding wheel G because it has become thinner than the intermediate region A2 due to the first-stage grinding. Furthermore, the grinding wheel G has not yet reached the axial core region A3, so it does not contact the axial core region A3 either. As a result, only the intermediate region A2 of the workpiece W is ground. After grinding of the intermediate region A2 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 13(d).

[0076] Next, the axial core region A3 of the processing surface of the workpiece W is ground (third-stage grinding). In this third-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50, and is set so that the axial core (rotation axis C2) of the workpiece W is included in the contact range of the grinding wheel G in a plan view (see FIGS. 14(a) and 14(b)). Next, as shown in FIG. 14(c), the grinding wheel G is advanced a predetermined distance onto the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the axial core region A3 of the workpiece W. Here, the outer peripheral region A1 and the intermediate region A2 do not come into contact with the grinding wheel G because they have become thinner than the axial core region A3 due to the first and second grinding stages. As a result, only the axial core region A3 of the workpiece W is ground. After grinding of the axial core region A3 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 14(d).

[0077] 15 to 17 are explanatory diagrams of another specific example of multi-stage grinding. The oscillation operation will be described in more detail below with reference to FIGS. 15 to 17, but the same components as those described with reference to FIGS. 1 to 11 will be assigned the same reference numerals and redundant description will be omitted. In the embodiment, as an example of multi-stage grinding, an example will be described in which three regions, namely, an outer peripheral region A1, an intermediate region A2, and an axial core region A3, are ground in stages. Also, an example will be described in which the relative positions of the grinding wheel G and the workpiece W in the direction perpendicular to the rotation axis (X direction) are set by moving the grinding wheel G.

[0078] In the other specific example of the multistage grinding process shown in FIGS. 15 to 17, the order of movement of the grindstone G is reversed compared to the specific example of the multistage grinding process shown in FIGS.

[0079] 15(a) is a plan view showing the positional relationship between the workpiece W and the grindstone G, and FIGS. 15(b) to 15(d) are front views showing the sequential changes in the positional relationship between the workpiece W and the grindstone G. FIG. First, the outer peripheral region A1 of the processing surface of the workpiece W is ground (first-stage grinding). In this first-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50 so that the axis (rotation axis C2) of the workpiece W is positioned inside the outermost periphery of the grinding wheel G in a planar view, and the innermost periphery of the outer peripheral region A1 of the workpiece W and the innermost periphery of the grinding wheel G coincide in a planar view (see FIGS. 15(a) and 15(b)). Next, as shown in FIG. 15(c), the grinding wheel G is advanced a predetermined distance along the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the outer peripheral region A1 of the workpiece W, but does not contact the intermediate region A2 (see FIG. 16) or the axis region A3 (see FIG. 17). As a result, only the outer peripheral region A1 of the workpiece W is ground. After grinding of the outer peripheral region A1 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 12(d).

[0080] Next, the intermediate region A2 of the processing surface of the workpiece W is ground (second-stage grinding). In this second-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50, so that the axis (rotation axis C2) of the workpiece W is positioned inside the outermost periphery of the grinding wheel G in a plan view, and the innermost periphery of the intermediate region A2 of the workpiece W coincides with the innermost periphery of the grinding wheel G (see Figures 16(a) and 16(b)). Next, as shown in Figure 16(c), the grinding wheel G is advanced a predetermined distance along the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the intermediate region A2 of the workpiece W. Here, the outer periphery region A1 does not come into contact with the grinding wheel G because it has become thinner than the intermediate region A2 due to the first-stage grinding. Furthermore, the grinding wheel G has not yet reached the axial core region A3, so it does not contact the axial core region A3 either. As a result, only the intermediate region A2 of the workpiece W is ground. After grinding of the intermediate region A2 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 16(d).

[0081] Next, the axial core region A3 of the processing surface of the workpiece W is ground (third-stage grinding). In this third-stage grinding, the grinding wheel G is linearly moved in the X direction by the linear drive mechanism 55 of the swing mechanism 50, and is set so that the axial core (rotation axis C2) of the workpiece W is included in the contact range of the grinding wheel G in a plan view (see FIGS. 17(a) and 17(b)). Next, as shown in FIG. 17(c), the grinding wheel G is advanced a predetermined distance onto the processing surface of the workpiece W to perform grinding. Both the grinding wheel G and the workpiece W are rotating, and the grinding wheel G contacts only the axial core region A3 of the workpiece W. Here, the outer peripheral region A1 and the intermediate region A2 do not come into contact with the grinding wheel G because they have become thinner than the axial core region A3 due to the first and second grinding stages. As a result, only the axial core region A3 of the workpiece W is ground. After grinding of the axial core region A3 is completed, the grindstone G is raised (retracted) to release it from contact with the workpiece W, as shown in FIG. 17(d).

[0082] In the multi-stage (three-stage) grinding of the surface of the workpiece W described in Figures 12 to 14 and Figures 15 to 17, grinding is performed in each stage region with carefully controlled balance between the grinding area and peripheral speed and the processing pressure applied by the grinding wheel G.

[0083] That is, in the first stage of grinding, the contact area between the outer peripheral region A1 and the grinding wheel G is wider than in the second and third stages of grinding, so the processing pressure is more easily dispersed. On the other hand, in the rotating workpiece W, the outer peripheral region A1 has a higher peripheral speed than the intermediate region A2 and the axial core region A3, so the amount of movement is greater.

[0084] Furthermore, in the second grinding stage, the contact area between the intermediate region A2 and the grinding wheel G is smaller than the contact area between the outer peripheral region A1 and the grinding wheel G in the first grinding stage, and the processing pressure tends to concentrate, but in the third grinding stage, the contact area is larger than the contact area between the axial region A3 and the grinding wheel G, and the processing pressure tends to disperse. Meanwhile, in the rotating workpiece W, the circumferential speed of the intermediate region A2 is lower than that of the outer peripheral region A1, and therefore the momentum is small, but the circumferential speed is higher than that of the axial region A3, and therefore the momentum is large.

[0085] Furthermore, in the third stage grinding, the contact area between the shaft core region A3 and the grinding wheel G is smaller than in the first and second stages of grinding, so the processing pressure tends to concentrate. On the other hand, in the rotating workpiece W, the shaft core region A3 has a lower peripheral speed than the outer peripheral region A1 and the intermediate region A2, so the momentum is small.

[0086] In this embodiment, the linear drive mechanism 55 of the processing device 10 can control the relative positions of the workpiece W and the grinding wheel G in the direction perpendicular to the rotation axis (X direction) with high precision, so that the grinding area of ​​each stage can be accurately set in multi-stage grinding. As a result, the balance between the grinding area and peripheral speed and the processing pressure of the grinding wheel G can be precisely controlled for each stage, and accurate grinding is performed for each multi-stage area. Therefore, more accurate processing can be performed than when grinding is performed by continuous oscillation in the X direction.

[0087] (compound oscillation) 18 to 21 are detailed explanatory diagrams illustrating the grinding process using the combined oscillation. (1) Tool advancement type during reciprocating swing Figure 18 is a detailed explanatory diagram of a specific example of the cutting tool advancement type during oscillating reciprocation. Figure 18(a) shows a schematic plan view, Figure 18(b) shows a schematic cross-sectional view, and Figure 18(c) shows the movement of the grinding wheel G and the cutting tool advancement (processing progress) using arrows etc.

[0088] (1-1) Function Function (a) The swinging motion in this example is a composite swinging motion in which the grinding wheel G performs machining on the workpiece W during the forward movement and the backward movement of the reciprocating motion. This is a synchronous motion in which the timing of the start of the swinging motion and the start of the cutting tool advancement coincides for both the forward and backward movements, and the timing of the end and stop of the swinging motion and the end and stop of the cutting tool advancement coincides for both the forward and backward movements. Function (b) Synchronous operation is a relationship in which the swinging action side is considered to be the main action and the cutting tool advancement side is subordinate and linked together. Function (c) If different speeds are set for the forward and backward swinging motion, the amount of cutting tool advancement in each case will change. Also, even if different cutting tool advancement speeds are set for the forward and backward swinging motion, the amount of cutting tool advancement in each case will also change. In the former case, the swing speed = the speed of the cutting tool's lateral movement changes, and in the latter case, the cutting tool advancement speed = the cutting tool's vertical movement (in this case, the cutting action speed) changes, so the cutting action differs. Settings can be made to suit each cutting content. Function (d) By providing a time delay for the start of oscillation during the pauses at the completion of the forward and backward oscillations, both the cutting tool advancement and oscillation pause simultaneously. At this time, a state in which the machining action is disabled is created, allowing both the surface of the grinding wheel G and the surface of the workpiece W to cool and rest. Function (e) In the example shown in Figure 18, the swing is stopped and the cutting tool advancement is paused at both ends of the swing reciprocating movement, but the swing stop positions are not limited to both ends of the reciprocating movement. For example, if the rotation axis of the workpiece coincides with the midpoint of the swing reciprocating movement, the swing and the advancement of the cutting tool may be stopped at the swing center, and the cutting tool advancement may be performed toward the swing movement end. Function (f) Of course, the swing movement range (the range from the swing start position to the swing end position) can be set in various ways, so different effects will be achieved if the swing movement range is set only from the center of the workpiece W to the front side of the swing, or if the swing movement range is set only to the rear side of the swing. Function (j) There is no limit to the number of swing stop points. It is possible to set multiple stops during forward swing or multiple stops during backward swing. The stop positions and number of stop points may be different when swinging forward and backward.

[0089] (1-2) Effects Effect (a) The grinding wheel G distributes the stress acting on the workpiece W by the advancement of the cutting tool, and the cutting tool grinding force can be applied efficiently over a wide area of ​​the workpiece W's machining surface. Effect (b) During the swinging movement, the processing stress from the cutting tool advancement is dispersed, suppressing vibration of the grinding wheel G, thereby preventing breakage of the workpiece W and damage to the peripheral portion. Effect (c) Since it is possible to stop the oscillation and the cutting tool advancement simultaneously, it is possible to provide a processing rest period for the grinding wheel G, allowing the grinding performance to recover by cooling. Effect (d) Since it is possible to stop the oscillation and the cutting tool advancement simultaneously, there is a period of time during which the machining action is ineffective, allowing the surface of the workpiece W to dissipate heat and suppressing the accumulation of thermal stress within the workpiece W. Effect (e) Since it is possible to stop the oscillation and the cutting tool advancement simultaneously, there is a period of time during which the machining action is ineffective, which promotes the discharge of machining residue (sludge) by the machining fluid and suppresses scratches on the workpiece W caused by cleaning the machined surface. Effect (f) Since it is possible to stop the oscillation and the cutting tool advancement simultaneously, in the state shown in Figure 18, the pressure of the cutting tool advancement is concentrated at the dead points at both ends of the oscillation movement, creating a no-load state, which suppresses the occurrence of device vibration and contributes to preventing damage to the peripheral edge of the workpiece W and fractures on the machined surface. Effect (g) As shown in Figure 18, when the rotation axis of the workpiece W and the center of the swing movement are aligned, the pressure of the cutting tool advancement is in a no-load state at both ends of the swing movement, so the uneven load on the bearing of the rotation axis of the workpiece W is alleviated, and wear on the rotation mechanism part of the workpiece W can be suppressed.

[0090] (2) Tool advancement type when swinging stops Figure 19 is a detailed explanatory diagram of a specific example of the cutting tool advancement type when swinging is stopped. Figure 19(a) shows a schematic plan view, Figure 19(b) shows a schematic cross-sectional view, and Figure 19(c) shows the swinging of the grinding wheel G and the movement of the cutting tool advancement (processing progress) with arrows etc.

[0091] (2-1) Function Function (a) The oscillating motion in this example is a compound oscillating motion in which the grinding wheel G continues to process the workpiece W while the reciprocating motion is stopped, and is a synchronous motion in which one is always at rest while the other is operating. Function (b) By setting a time delay for the start of oscillation during the pause after the cutting tool advancement operation is completed, both the cutting tool advancement and oscillation can be paused simultaneously. At this time, a state in which the machining action is disabled is created, allowing the cutting tool surface and the surface of the workpiece to cool and rest. Function (c) The cutting tool advancement side is considered to be the main side, and the oscillating action side is subordinate and linked to it. Function (d) The pressure position due to the advancement of the cutting tool can be concentrated at any point on the workpiece W. Function (e) By setting multiple stopping points for the oscillation, the machining action point of the cutting tool can be displaced intermittently. This allows the aforementioned multi-stage in-plane machining (multi-stage grinding process) to be performed. Function (f) In the example shown in Figure 19, the swing is stopped and the cutting tool advances at both ends of the swing reciprocating movement, but the swing stop position is not limited to this. For example, if the rotation axis of the workpiece W and the center point of the swing reciprocating movement amount coincide, the operation may be set so that the swing stops at the swing center and the cutting tool advances. Function (g) In the above case, while the cutting tool is in the process of machining, the action is the same as in conventional machining without oscillation, but by moving the grinding wheel G sideways by oscillation while the cutting tool is stopped, it is possible to smooth the machined surface of the workpiece W, to clean by actively discharging machining residue (sludge), and to actively cool the machining area by using machining fluid. Function (h) In the above case, by repeating the lateral movement back and forth by swinging while the cutting tool is stopped, the effect of leveling the machined surface and the functions of cleaning the machined surface and cooling the machined surface are further improved. Function (i) Of course, the swing stop position can be set in various ways, so different effects will be achieved if it is set only on the swing front side from the center of the workpiece W, or if it is set only on the swing rear side. Function (j) There are no restrictions on the stopping positions or number of stopping points of the swing. The stopping positions and number of stopping points may be different when moving forward and backward.

[0092] (2-2) Effects Effect (a) The stress that presses the grinding wheel G against the workpiece W can be intentionally concentrated at a targeted location, causing the grinding wheel G to dig into the workpiece W and trigger shearing. Effect (b) Because the above-mentioned stress concentration areas can be displaced by the oscillation, unlike processing without oscillation, there is no local continuous stress concentration. Therefore, while obtaining pressure at the initial stage of shearing, it is possible to suppress the accumulation of stress strain on the surface of the workpiece W and alleviate the accumulation of thermal stress. Effect (c) Since the cutting tool moves laterally by swinging while the cutting action is disabled while the cutting tool is stopped, the machining surface of the workpiece can be repeatedly homogenized, smoothed, and flattened.

[0093] (3) Tool advancement type when swinging forward Figure 20 is a detailed explanatory diagram of a specific example of the cutting tool advancement type during forward swing motion. Figure 20(a) shows a schematic plan view, Figure 20(b) shows a schematic cross-sectional view, and Figure 20(c) shows the swing of the grinding wheel G and the movement of the cutting tool advancement (processing progress) with arrows etc.

[0094] (3-1) Function Function (a) The oscillating action in this example is a composite oscillating action in which the grinding wheel G performs machining on the workpiece W only during the forward movement of the reciprocating motion, and is a synchronized action exclusively for one-way machining action in which the cutting tool advancement is always stopped during the backward movement of the oscillating motion. Function (b) By setting the cutting tool advancement speed high and also setting the oscillation retraction speed at which the cutting tool advancement is stopped high, high-speed and highly efficient machining can be achieved. Function (c) When the retraction speed of the swing is set low while the cutting tool is stopped, the cutting tool moves horizontally without any machining force, which allows for the rough surface generated by high-speed machining to be smoothed out. Also, since the cutting tool does not necessarily advance when the swing advances, the swing can be made to reciprocate while the cutting tool is stopped to fully smooth out the machined surface, and then the cutting tool can be advanced again with the swing advance. Function (d) As shown in the example in Figure 20, when the right half of the workpiece W is set as the oscillation range, the grinding wheel G is always performing counter grinding (reverse machining), so the processing action of the grinding wheel G is strongest. In this case, the initial stage of the cutting tool movement is the initial stage of the forward oscillation, so the area of ​​the workpiece W is small, and the stress is small, so the load on the workpiece is small and damage is minimal. As the oscillation advances, the cutting tool also advances deeper, so the stress of the processing action increases, but because it moves toward the center of the workpiece W, the area increases in proportion to this movement, so the load is dispersed and damage does not increase. Function (e) In the above-mentioned counter (reverse) grinding, the forward movement of the oscillation displaces the radial position at which the grinding wheel G acts on the workpiece W, causing a change in the relative speed. Near the center of the workpiece W, the rotational speed of the workpiece becomes extremely small, and the machining action is left to the rotational speed of the grinding wheel G. However, this can be resolved by adjusting the rotational speed of the workpiece W and the grinding wheel G in conjunction with changes in the range of machining action due to changes in the relative position between the workpiece W and the grinding wheel G in the oscillation position, and changes in the relative speed between the workpiece W and the grinding wheel G.

[0095] (3-2) Effects Effect (a) By utilizing the outer periphery of the grinding wheel G, processing can be performed in a direction that spreads as if pushing out from the tip of the convex curved shape, resulting in a powerful effect. Effect (b) Suitable for high-speed and high-efficiency machining of highly tough materials. Effect (c) Suitable for high-speed and high-efficiency machining when the material thickness is large in the initial stage of machining. Effect (d) It is suitable for removing unevenness when the processed surface is rough, such as in the early stages of the manufacturing process. Effect (e) Since the exposed area of ​​the workpiece W is large, the cooling effect of the machining fluid is large and efficient. Effect (f) The exposed area of ​​the workpiece W is large, so that processing residue (sludge) can be efficiently discharged. Effect (g) The working area of ​​grinding wheel G is small, so the burden on the cutting tool can be reduced even during high-load processing. Effect (h) From the beginning to the end of the tool's swing forward movement, the machining surface area increases in proportion to the cutting tool's machining depth, so the resistance of the grinding wheel G increases but the machining surface pressure on the workpiece W is kept uniform. Effect (i) At the beginning of the cutting tool advancement during the oscillating forward movement, the processing stress of the grinding wheel G is concentrated in a narrow area of ​​the workpiece W, but since the cutting tool advancement depth is shallow, the load is small, and since the oscillating movement from the outer periphery toward the center causes the direction to escape from the outer periphery, damage to the outer periphery of the workpiece W can be suppressed.

[0096] (4) Tool advancement type when swinging forward Figure 21 is a detailed explanatory diagram of a specific example of the cutting tool advancement type during swing retreat. Figure 21(a) shows a schematic plan view, Figure 21(b) shows a schematic cross-sectional view, and Figure 21(c) shows the swing of the grinding wheel G and the movement of the cutting tool advancement (processing progress) with arrows etc.

[0097] (4-1) Function Function (a) The oscillating action in this example is a composite oscillating action in which the grinding wheel G performs machining on the workpiece W only during the backward movement of the reciprocating motion, and is a synchronized action exclusively for one-way machining action in which the cutting tool advancement is always stopped during the forward oscillating movement. Function (b) By setting the cutting tool advancement speed low and also setting the oscillation forward speed at which the cutting tool advancement is stopped low, slow and gentle processing can be performed with low load and gentle on the material. Function (c) When the forward swing speed at which the cutting tool advancement is stopped is set low, the cutting tool moves horizontally without any processing force, which allows for the effect of finely scraping the processed surface. Also, since the cutting tool advancement is not required when the cutting tool is retracted, repeated swing back and forth is more effective. Function (d) As in the example shown in Figure 21, when the left half of the workpiece W is set as the oscillation range, grinding wheel G is always grinding forward (machining in the same direction), so the machining action of grinding wheel G is the gentlest. In this case, the initial stage of tool advance is the initial stage of swing retraction, so the area of ​​the workpiece W is small, and the stress is small, so the load on the workpiece W is small, resulting in little damage. As the swing retracts, the tool advances deeper, so the stress of the machining action increases, but because it moves toward the center of the workpiece W, the area increases in proportion to this movement, so the load is distributed and damage does not increase. Function (e) In the above-mentioned forward (same direction) grinding, the radial position at which the grinding wheel G acts on the workpiece W changes due to the backward movement of the oscillation, causing a change in the relative speed. Near the center of the workpiece W, the rotational speed of the workpiece becomes extremely small, and the machining action is left to the rotational speed of the grinding wheel G. However, this can be resolved by adjusting the rotational speed of the workpiece W and the rotational speed of the grinding wheel G in conjunction with changes in the range of machining action due to changes in the relative position between the workpiece W and the grinding wheel G in the oscillation position, and changes in the relative speed between the workpiece W and the grinding wheel G. Function (f) In the forward (same-direction) grinding described above, by adjusting the rotational speed of the workpiece W and the grinding wheel G in accordance with changes in the relative position of the workpiece W and the grinding wheel G in the oscillation position, which changes the range of the grinding action, and by adjusting the rotational speed of the workpiece W and the grinding wheel G in accordance with changes in the relative speed between the workpiece W and the grinding wheel G, it is possible to switch from an action in which the grinding wheel G leads (the grinding wheel G overtakes the workpiece W) to an action in which the workpiece W leads (the grinding wheel G is overtaken by the workpiece W). This changes the direction of action of the grinding wheel G, and for example, the tip of the diamond abrasive grains on the grinding wheel can be changed from a state in which the grinding action is performed on the front side of the rotation direction to a state in which the grinding action is performed on the rear side of the rotation direction. This action eliminates clogging of the grinding wheel G and reduces the burden on the grinding wheel G, thereby maintaining tool performance and extending the tool life. Function (g) This change in the direction of cutting tool action is possible at any time during processing without stopping the processing, so it can be activated periodically based on time or processing volume, or arbitrarily by monitoring the load on the grinding wheel G.

[0098] (4-2) Effects Effect (a) The inner circumference of the grinding wheel G can be used to process in a direction that gathers the material from the center of the concave curved shape, resulting in a gentle processing action. Effect (b) Suitable for soft processing of highly brittle materials and quality-first processing. Effect (c) Suitable for finishing when the material thickness is small at the final stage of processing, and for improving surface roughness. Effect (d) Suitable for surface smoothing processing when transferring to the polishing process, such as in the later stages of the manufacturing process. Effect (e) Although the exposed area of ​​the workpiece W is small, because the machining is performed in the forward direction, the machining fluid is easily drawn into the inside of the workpiece W, and the lubricating effect on the machined surface is large and efficient. Effect (f) Although the exposed area of ​​the workpiece W is small, forward machining has the effect of actively pushing out the machining residue (sludge) without interfering with its discharge. Effect (g) Because the processing area of ​​the grinding wheel G is large, the surface pressure of the grinding wheel G decreases, and stress accumulation on the surface of the workpiece W is alleviated. Effect (h) From the beginning to the end of the cutting tool movement during the retraction of the swing, the working surface area increases in proportion to the depth of the grinding wheel G, so the working surface pressure is kept uniform. Effect (i) In the initial stage of the cutting tool movement during retraction, the curved shapes of the workpiece W and grinding wheel G are similar (arcs in the same direction), so the contact angle at the outer periphery of the workpiece is shallow, which reduces the processing load and helps prevent damage to the periphery. Also, when the cutting tool moves from the outer periphery toward the center, the direction on the normal to the inside of the cutting tool curve where the processing force acts is always toward the inside of the workpiece W, which helps prevent damage to the periphery of the workpiece W.

[0099] (Selection of swing motion and feed progression) In the processing device 1 according to this embodiment, the swinging movement and the feed advance may be selected from the viewpoint of the workpiece W and the processing of the workpiece W. Furthermore, the processing device 1 may perform processing that associates a mixed operation of the swinging movement and the feed advance, or multi-stage processing, based on data acquired by profile measurement. As an example, the selection of the swinging movement and the feed advance is given below.

[0100] (1) The oscillation movement and feed advancement are selected based on the characteristics of the workpiece W (hardness, toughness / brittleness, etc.). (2) Select the swing movement and feed progress based on the size (diameter and thickness) of the workpiece W. (3) Select the swing movement and feed advancement based on the purpose of machining (priority on machining speed = emphasis on availability / priority on machining quality = emphasis on productivity). (4) Select the swing movement and feed advancement depending on the processing content (flattening purpose / improving surface roughness purpose / thinning purpose, etc.). (5) The swing movement and feed movement are selected depending on the progress of the machining (the amount of grinding, the remaining amount in the thickness measurement during the process, etc.). (6) The swing movement and feed advance are selected based on the quality of the processing (profile measurement results during grinding).

[0101] As described above, the processing apparatus 10 according to the embodiment is a processing apparatus that grinds or polishes a workpiece W to be processed. The processing apparatus 10 includes the tool spindle 42 as a first rotating body that holds and rotates the grinding wheel G, which is a processing tool, the spindle 311 as a second rotating body that holds and rotates the workpiece W, a feed screw 45 as a first driving unit that moves at least one of the grinding wheel G and the workpiece W relatively closer to each other along the rotation axes C1 and C2 of the tool spindle 42 and the spindle 311, a swing mechanism 50 as a second driving unit that swings at least one of the tool spindle 42 and the spindle 311 in a direction perpendicular to the rotation axes C1 and C2 (X direction), and a control unit 75 that controls the processing pressure on the workpiece W. The swing mechanism 50 has a linear driving mechanism 55 that converts the rotational movement into the swinging movement in direct proportion.

[0102] Therefore, the change in the distance between the rotation axes C1 and C2 of the tool spindle 42 and the spindle 311 by the swing mechanism 50, in other words, the swing operation by the swing mechanism 50, converts the rotation operation into a swing operation in direct proportion, thereby improving the controllability of the swing operation based on the rotation operation. As a result, the processing accuracy of the grinding or polishing process accompanied by the swing operation can be improved.

[0103] Furthermore, the linear drive mechanism 55 of the swing mechanism 50 of the processing device 10 according to the embodiment includes a screw 52 and a ball screw 521 that linearly move at least one of the tool spindle 42 and the spindle 311 in the X direction, and a motor 53 that axially rotates the screw 52. This allows the rotational motion of the motor 53 to be converted into a swinging motion with high precision by the screw 52 and the ball screw 521.

[0104] Furthermore, the linear drive mechanism 55 of the swing mechanism 50 of the processing device 10 according to the embodiment may have a rack gear and pinion gear that mesh with each other to linearly move at least one of the tool spindle 42 and the spindle 311 in the X direction, and a motor 53 that rotates the pinion gear. This allows the rotational motion of the motor 53 to be transmitted from the pinion gear to the rack gear and converted into a swinging motion with high precision.

[0105] Moreover, the processing method according to the embodiment is a processing method for grinding or polishing a workpiece W to be processed. This processing method includes a first processing step of pressing a grinding stone G rotated by the tool spindle 42 against the workpiece W rotated by the spindle 311 to grind or polish a first region of the workpiece W, a release step of releasing the grinding stone G from pressing against the workpiece W after the first processing step, a movement step of using the swing mechanism 50 to move at least one of the tool spindle 42 and the spindle 311 by a predetermined amount in a direction (X direction) perpendicular to the rotation axes C1 and C2, and a second processing step of pressing the grinding stone G rotated by the tool spindle 42 against the workpiece W rotated by the spindle 311 to grind or polish a second region of the processing surface of the workpiece W after the movement step.

[0106] This allows the processing of the first area of ​​the workpiece W and the processing of the second area of ​​the workpiece W to be carried out in stages by utilizing the change in the distance between the rotation axes C1, C2 of the tool spindle 42 and the spindle 311, in other words, the swinging motion of the swinging mechanism 50. As a result, highly accurate processing can be performed taking into consideration the balance between the processing area and peripheral speed in the first and second areas and the processing pressure of the processing tool. As a result, the processing accuracy of the grinding or polishing process accompanied by the swinging motion can be improved.

[0107] Furthermore, in the movement step of the processing method according to the embodiment, the swing mechanism 50 converts the rotational motion into a swinging motion in direct proportion to move at least one of the tool spindle 42 and the spindle 311 in the X direction. This allows the swing mechanism 50 to change the distance between the rotation axes C1, C2 of the tool spindle 42 and the spindle 311, in other words, converts the rotational motion into a swinging motion in direct proportion to the swinging motion of the swing mechanism 50, thereby improving the controllability of the swinging motion based on the rotational motion.

[0108] Furthermore, in the processing method according to the embodiment, the first region is more distal to the rotation axis of the workpiece than the second region. The contact area (processing area) between the processing tool and the first region, which is distal to the rotation axis of the workpiece W, is larger than the contact area (processing area) between the grinding wheel G and the second region, which is closer to the rotation axis of the workpiece W. On the other hand, the processing pressure of the grinding wheel G per unit area is higher in the second region than in the first region. Therefore, high-precision processing can be performed by taking into consideration the balance between the processing area and the processing pressure of the grinding wheel G.

[0109] As described above, the present invention provides a processing apparatus and processing method capable of improving the processing accuracy of grinding or polishing processes involving an oscillating motion. Furthermore, while the present invention is preferably applied primarily to wafers, semiconductor materials such as ceramics, and ultra-hard materials, similar high-precision processing techniques are equally applicable to conventional structural materials such as steel. Therefore, the subject matter of the present invention is not limited to the ultra-hard materials described above. Furthermore, because the profile measuring device 80 can recognize the shape of the workpiece W, shapes other than circular can also be measured, and because the measurement is optical, there are fewer limitations on the thickness of the workpiece W.

[0110] (Other embodiments) In the above embodiments, the vertical-type apparatus in which the rotation axes of the tool spindle and work spindle are oriented substantially vertically has been described. However, the present invention is not limited to this configuration and can be similarly applied to horizontal-type apparatus in which these rotation axes are oriented substantially horizontally. In the illustrated configuration, the lower work spindle forms the fixed spindle described in the prior art, and the upper tool spindle forms the axially driven spindle. However, the vertical relationship between the fixed side and the driven side may be reversed. Furthermore, while the above embodiments oscillate the tool spindle 42 side (the grinding wheel G side), the spindle 311 side (the workpiece W side) may also be oscillated. Furthermore, both the tool spindle 42 side (the grinding wheel G side) and the spindle 311 side (the workpiece W side) may also be oscillated.

[0111] As already mentioned, the present invention can also be applied to a polishing apparatus (lapping apparatus). Figure 22 is an enlarged view of only the contact area between the tool and workpiece in a polishing process to which the present invention is applied; other components are omitted from the illustration. In Figure 22, a tool spindle 135 extends from below, and the tool spindle 135 rotates a lap platen 136 in the direction of arrow γ by driving a motor (not shown). A polishing liquid (slurry) is applied to the lap platen 136, enabling the workpiece to be polished. For convenience, the lap platen 136 will be considered a tool in this specification, and the spindle that drives the lap platen 136 will be referred to as the tool spindle 135.

[0112] A work spindle 138 extends from above facing the lapping platen 136, and a workpiece W is fixed to a workpiece holder 139 at the tip of the work spindle 138. In this embodiment, the workpiece holder 139 is configured as a vacuum chuck, i.e., it uses a vacuum to securely hold the workpiece W. The workpiece holder 139 and the lapping platen 136 are configured to be adjustable so that they are parallel, so that the workpiece W fixed to the workpiece holder 139 can always be kept parallel to the lapping platen 136. The parallel adjustment can be made by, for example, arranging adjustable lock bolts at four radial locations on the workpiece holder 139.

[0113] The polishing apparatus shown in FIG. 22 is provided with a mechanism for oscillating the workpiece W or the lapping platen 136, and has the same configuration and control as the processing apparatus 10 according to the embodiment, specifically, by controlling the linear movement of at least one of the workpiece W and the lapping platen 136 in the X direction by the linear drive mechanism 55 shown in FIG. 1, it is possible to improve the processing accuracy and / or processing efficiency.

[0114] Furthermore, although the grinding apparatus of Fig. 1 has a one-to-one relationship between the workpiece W and the grinding wheel G, and the polishing apparatus of Fig. 22 has a one-to-one relationship between the work holder 139 and the lapping platen 136, there are no limitations on the combinations, such as one-to-many or many-to-many. For example, Fig. 23 is a side view illustrating a multi-axis polishing apparatus to which the present invention is applied. The processing apparatus 10 shown in Fig. 23 is a polishing apparatus, and is equipped with two work holders 139 for one lapping platen 136.

[0115] Each of the two work holders 139 is provided with a work spindle 138. The two work spindles 138 are arranged side by side at a predetermined interval and are each rotatable by a spindle motor 137. Each work holder 139 is also provided so as to be movable in the vertical direction, allowing the distance between the lapping platen 136 and the workpiece W to be set. The lapping platen 136 is rotatable by a platen motor 134.

[0116] The work spindle 138 and the work holder 139 are each supported by a base 41. Each base 41 is provided with a linear drive mechanism 55 (e.g., a screw 52, ​​a ball screw 521, and a motor 53) of the swing mechanism 50. This allows each base 41 to move linearly independently in a direction perpendicular to the rotation axis of the work spindle 138. The linear drive mechanism 55 converts the rotational motion of the motor 53 into swing motion in direct proportion, making it possible to control the swing motion of each of the two work spindles 138 based on the rotational motion of the motor 53 with high precision. Furthermore, it becomes possible to control the swing motion (swing direction, swing speed, swing amount) of the two work spindles independently.

[0117] The multi-axis configuration described above can also be applied to a grinding device. The number of multi-axis units is not limited to two, and may be three or more. [Industrial Applicability]

[0118] The present invention can be used in industrial fields such as grinding and polishing for finishing the surfaces of various materials, and is particularly effective in efficiently grinding and polishing ultra-hard materials such as ceramics and semiconductor wafers with high surface accuracy. [Explanation of symbols]

[0119] 10 Processing equipment 20 base (main frame) 30 Work holding part 31 Holding table 311 Spindle 312 Bearings 313 Rotating stage (second rotating body) 32 Motor (power source) 33 Belt (power transmission means) 40 Tool rotation drive unit 41 Frame 42 Tool spindle (first rotating body) 421 Nut part 43 Spindle cover 45 lead screw 46 Tool rotation drive motor (power source) 47 Belt (power transmission means) 48 Axial drive motor 49 cylinders 50 Swing mechanism 51 Guide rail 52 Screw 521 Ball screw 53 Motor (power source) 55 Linear drive mechanism 61a to 61d, 62a to 62d Detection sensors 70 Control device 71 Communications Department 72 Load monitor section 73 Memory section 74 Profile calculation unit 75 Control Unit 80 Profile Measuring Instrument A1 Outer region A2 intermediate area A3 axis center area C1, C2 rotation axis G grindstone L1 Distance to the rotation stage L2 Distance to the top surface of the workpiece before grinding L3 Distance to the top surface of the workpiece after grinding P1 Top dead center position P2 Confectionery store location P3 intermediate position double work

Claims

1. A processing device for grinding or polishing a workpiece to be processed, a first rotating body that holds and rotates the processing tool; a second rotating body that holds the workpiece and rotates it; a first drive unit that moves at least one of the processing tool and the workpiece relatively closer to each other in a rotation axis direction of the first and second rotating bodies; a second drive unit that swings at least one of the first and second rotors in a direction perpendicular to the rotation axis; a control unit that controls the distance between the rotation axes of the first and second rotors by the second drive unit and the processing pressure of the processing tool on the workpiece by the first drive unit; Equipped with The processing apparatus is characterized in that the second drive unit has a linear drive mechanism that converts the swinging motion in direct proportion to the swinging motion.

2. The linear drive mechanism of the second drive unit is a screw and a ball screw that linearly move at least one of the first and second rotating bodies in the vertical direction; a motor for axially rotating the screw; 2. The processing apparatus according to claim 1, further comprising:

3. The linear drive mechanism of the second drive unit is a rack gear and a pinion gear that mesh with each other and linearly move at least one of the first and second rotors in the vertical direction; a motor that rotates the pinion gear; 2. The processing apparatus according to claim 1, further comprising:

4. A processing method for grinding or polishing a workpiece to be processed, comprising: a first processing step in which a first driving unit presses a processing tool rotated by a first rotating body against the workpiece rotated by a second rotating body to grind or polish a first region of the workpiece; a release step of releasing the pressing of the processing tool against the workpiece after the first processing step; a moving step in which, after the releasing step, a second driving unit moves at least one of the first and second rotating bodies by a predetermined amount in a direction perpendicular to the rotation axis; a second processing step in which, after the moving step, the first driving unit presses the processing tool rotated by the first rotating body against the workpiece rotated by the second rotating body to grind or polish a second region of the workpiece; A processing method comprising the steps of:

5. 5. The processing method according to claim 4, wherein in the moving step, the second drive unit moves at least one of the first and second rotating bodies in the vertical direction by converting the swinging motion in direct proportion to the swinging motion.

6. The method of claim 4 , wherein the first region is further distal to the rotation axis of the workpiece than the second region.

Images