JP4288974B2 - Cutting method of ceramic green sheet laminate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for cutting a ceramic green sheet laminate, and particularly to an improvement in a camera focusing method for sensing a position to be cut.
[0002]
[Prior art]
For example, in order to efficiently mass-produce monolithic ceramic electronic components such as monolithic ceramic capacitors, a ceramic green sheet laminate from which a plurality of monolithic ceramic electronic components are to be taken out is first produced, and a plurality of monolithic ceramic electronic components are to be taken out therefrom. The ceramic green sheet laminate is cut. The ceramic green sheet laminate has a structure in which a plurality of ceramic green sheets having internal electrodes formed along a specific interface are laminated.
[0003]
In cutting the ceramic green sheet laminate described above, the following steps are usually performed.
[0004]
First, the ceramic green sheet laminate to be cut is placed on the table mounting surface. Next, the ceramic green sheet laminate on the mounting surface is cut by a cutting mechanism that performs, for example, pressing with a cutting blade. The table and the cutting mechanism are configured to be relatively movable. After the above-described cutting, the relative movement is performed, and the cutting and the relative movement are repeated a plurality of times. In the green sheet laminate, a plurality of cut surfaces arranged in a predetermined direction are formed, and as a result, a state in which the ceramic green sheet laminate is cut along the plurality of cut surfaces is obtained.
[0005]
As described above, when the cutting that proceeds in the predetermined direction is finished, the ceramic green sheet laminate is cut into a plurality of strips. Next, the table and the cutting mechanism are relatively rotated by 90 degrees, and the same cutting and relative movement are repeated. As a result, the ceramic green sheet laminate is cut into a plurality of chips.
[0006]
When performing the cutting method as described above, the cutting position must be accurately controlled. For this reason, a method has been proposed in which internal electrodes are exposed at opposite end faces of the ceramic green sheet laminate to be cut, and cutting is performed while monitoring both end faces at which the internal electrodes are exposed with a camera. (For example, see Patent Document 1).
[0007]
[Patent Document 1]
JP 2002-184646 A
[0008]
[Problems to be solved by the invention]
The technique described in Patent Document 1 described above is a technique that is based on the premise that the ceramic green sheet laminate to be cut is accurately aligned on the table. This is because if the ceramic green sheet laminate is misaligned on the table mounting surface, the image pick-up by the camera is not focused, which hinders control by image processing. Therefore, a technique for properly aligning the ceramic green sheet laminate on the mounting surface is required.
[0009]
As a technique for the above-described alignment, first, there is a method of performing alignment manually. That is, this is a method in which the ceramic green sheet laminate is manually placed on the placement surface of the table and the ceramic green sheet laminate is moved on the placement surface so as to be in focus with the camera. However, this method has a problem that it takes a relatively long time for alignment.
[0010]
As another technique for alignment, there is a method using a guide. FIGS. 14 and 15 are for explaining problems that may be encountered in the method using such a guide. With reference to FIGS. 14 and 15, the mounting surface 2 of the table 1 will be described. A guide 3 is provided in the vicinity of the end. The ceramic green sheet laminate 4 placed on the placement surface 2 is moved so that its predetermined end surface 5 comes into contact with the guide 3. Thus, the ceramic green sheet laminated body 4 in the state in which the end surface 5 is in contact with the guide 3 is located at a position focused on the camera (not shown).
[0011]
However, as described above, the alignment method using the guide 3 has the following problems.
[0012]
When the thickness of the ceramic green sheet laminate 4 is reduced with the miniaturization of the multilayer ceramic electronic component to be obtained, as shown in FIG. 14, floating occurs in part, and the alignment by the guide 3 becomes difficult. . Further, when the ceramic green sheet laminate 4 is further thinned, as shown in FIG. 15, the end of the ceramic green sheet laminate 4 may sink under the guide 3, and in this case also, the ceramic green sheet laminate 4 4 is difficult to properly align. Furthermore, the presence of the guide 3 may lead to a complicated cutting device.
[0013]
On the other hand, if a camera having an automatic focusing (autofocus) function is used, the above-described problems relating to alignment can be avoided to some extent. However, a camera having an automatic focusing function has a problem that the equipment cost increases. Further, when the thickness of the ceramic green sheet laminate is reduced, this end face is reduced, and when the number of laminated layers in the ceramic green sheet laminate is small, the number of exposed internal electrodes is reduced. It becomes difficult to determine whether or not it is in the focusing state, and it becomes difficult to ensure the reliability of the automatic focusing function.
[0014]
In addition, as described above, after the cutting proceeding in a predetermined direction is finished, the table and the cutting mechanism are relatively rotated by 90 degrees, and in this state, when cutting is performed again, the relative rotation is performed. Depending on the center position accuracy, it may be necessary to refocus the camera after rotation.
[0015]
Accordingly, an object of the present invention is to provide a method for cutting a ceramic green sheet laminate that can solve the above-described problems.
[0016]
[Means for Solving the Problems]
In order to carry out the method for cutting a ceramic green sheet laminate according to the present invention, a cutting device having the following configuration is used.
[0017]
That is, this cutting device is for placing a ceramic green sheet laminate to be cut, and has a rectangular shape having first and second sides facing each other and third and fourth sides facing each other. And a ceramic green sheet laminate placed on the table mounting surface, which is rotatable about a predetermined rotation axis passing through the center of the mounting surface in a direction orthogonal to the center of the mounting surface. A cutting mechanism for cutting the substrate with a linearly extending cutting surface, and imaging in directions from the position outside the table toward two opposite sides of the mounting surface, respectively, and for focusing And at least one pair of cameras, the distance of which can be changed.
[0018]
The above-mentioned table is movable relative to the cutting mechanism and the camera in the direction in which the placement surface extends. In addition, the cutting device is configured to perform the cutting operation by the cutting mechanism and the relative movement of the table at each position to be cut of the ceramic green sheet laminate determined by processing the image captured by the camera. Is repeated a plurality of times, so that the ceramic green sheet laminate is cut along cut surfaces arranged in a predetermined direction.
[0019]
  In the method for cutting the ceramic green sheet laminate according to the present invention, the ceramic green sheet laminate has a planar rectangular shape having first and second end faces facing each other and third and fourth end faces facing each other. thingA sensing mark is attached to each region along the first and second end faces.Is prepared, and the following process is performed using the above-described cutting apparatus.
[0020]
First, the ceramic green sheet laminate is placed on the placement surface so that the first and second end faces of the ceramic green sheet laminate extend in directions parallel to the first and second sides of the placement surface, respectively. The placing process is carried out.
[0021]
  Next, the ceramic green sheet laminate is cut in the vicinity of the first and second end faces by a cutting mechanism, thereby forming opposing pre-cut faces.And exposing the above-mentioned sensing mark on the preliminary cut surface.At the same time, a preliminary cutting step of removing a portion outside the preliminary cutting surface is performed.
[0022]
Next, a forward rotation process is performed in which the table is rotated 90 degrees in the forward direction from the original position around the rotation axis.
[0023]
  Next, pre-cut surfaceSensing mark exposed toThe cutting operation by the cutting mechanism and the relative movement of the table are repeated a plurality of times at each position to be cut of the ceramic green sheet laminate determined by processing the image obtained by imaging the camera. The ceramic green sheet laminate is cut along a primary cut surface extending in a direction orthogonal to the preliminary cut surface while being arranged in the direction in which the preliminary cut surface extends, and at both ends of the plurality of primary cut surfaces. A primary cutting step is performed to remove the portion outside the one located.
[0024]
Next, a reverse rotation process is performed in which the table is rotated 90 degrees in the reverse direction around the rotation axis and returned to the original position.
[0025]
Next, the ceramic green sheet laminate determined by processing images obtained by capturing images of the primary cut surfaces obtained by the primary cutting step at both ends with a camera. At each position to be cut, the cutting operation by the cutting mechanism and the relative movement of the table are repeated a plurality of times, so that the ceramic green sheet laminate is arranged in the direction of extending the primary cutting plane and orthogonal to the primary cutting plane. A secondary cutting step of cutting along a secondary cutting surface extending in the direction of the cutting is performed.
[0026]
In carrying out the cutting method using the cutting apparatus as described above, the present invention is characterized by having the following configuration in order to solve the technical problem described above.
[0027]
  First, the sensing mark has a length that can be exposed on the preliminary cutting surface formed in the preliminary cutting step regardless of the alignment error of the ceramic green sheet laminate on the mounting surface in the mounting step. And a shape extending in a direction perpendicular to the second end face.
  Also,The address of the rotation axis, the addresses of the first and second sides of the placement surface when in the original position, the addresses of the third and fourth sides of the placement surface after rotation in the forward direction, Each address of the camera focused on each of the third and fourth sides of the placement surface when in position and each of the first and second sides of the placement surface after rotating in the forward direction Each address of the camera focused on, each address of the preliminary cut surface obtained by the preliminary cutting step, and each address of the primary cut surface at both ends obtained by the primary cutting stepTheObtained in advance based on actual measurementsThe process is further provided.
[0028]
  In order to carry out the primary cutting process, the camera uses the rotation axis address, the addresses of the first and second sides of the placement surface when in the original position, and the placement surface after rotating in the forward direction. Each address of the camera focused on each of the first and second sides ofPre-soughtIt is brought to the position focused on the preliminary cut surface, which is obtained by the arithmetic processing using each address of the preliminary cut surface.
[0029]
  On the other hand, in order to carry out the secondary cutting process, the camera has the rotation axis address, the addresses of the third and fourth sides of the mounting surface after rotating in the forward direction, and the mounting surface at the original position. Each address of the camera focused on each of the third and fourth sides ofPre-soughtIt is brought to a position focused on the primary cut surfaces at both ends, obtained by an arithmetic process using each address of the primary cut surface.
[0032]
  This inventionIn the ceramic green sheet laminate, a second sensing mark is provided in each region along the third and fourth end faces.furtherAttached is prepared, and the primary cutting process is performed so that the second sensing mark is exposed on the primary cutting surfaces at both ends, and in the secondary cutting process, the sensing mark is imaged by the camera. It may be.
[0033]
Preferably, the present invention further includes a step of preparing an alignment table for aligning the ceramic green sheet laminate according to the outer shape reference, and a step of aligning the ceramic green sheet laminate on the alignment table. In this case, the placing step includes a step of transporting and placing the ceramic green sheet laminate aligned on the alignment table on the placing surface.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
1 to 12 are for explaining an embodiment of the present invention.
[0035]
Here, FIG. 1 and FIG. 2 are plan views showing the table 11 provided in the cutting apparatus used for carrying out the cutting method according to this embodiment together with the coordinate axes for displaying addresses.
[0036]
The table 11 is for placing a ceramic green sheet laminate to be described later, and has a square having first and second sides 12 and 13 facing each other and third and fourth sides 14 and 15 facing each other. A mounting surface 16 having a shape, preferably a square shape, is formed. The table 11 is rotatable around a predetermined rotation axis 17 that passes in the direction orthogonal to the center of the mounting surface 16. This rotation is driven by a motor such as a direct drive motor, and the rotation angle can be recognized and controlled by an encoder or a motor control value.
[0037]
The table 11 is movable in the direction in which the mounting surface 16 extends with respect to a cutting mechanism and cameras 18 and 19 (see, for example, FIGS. 3 and 4) used in cutting described later. The direction of movement is the direction of the Y axis in FIGS. 1 and 2. This movement is driven by, for example, a servo motor or a linear motor, so that the table 11 can be moved to a designated position. The amount of movement in the Y-axis direction can be recognized and controlled by movement data given to a servo motor or linear motor, or a scale.
[0038]
It should be noted that the table 11 and the cutting mechanism only need to be relatively movable, and the table 11 may be fixed and the cutting mechanism or the like may be moved.
[0039]
In FIG. 1 and FIG. 2, etc., a sign 20 is shown on the table 11 so that the rotation state of the table 11 can be easily understood from each drawing. FIG. 1 shows a state in which the table 11 is in the original position, and FIG. 2 shows a state in which the table 11 is rotated 90 degrees around the rotation shaft 17 from the original position in the forward direction (clockwise in this example).
[0040]
With respect to such a table 11, the following addresses are obtained in advance based on actual measurements and stored.
[0041]
First, the Y-axis direction address TC of the rotating shaft 17 is obtained. Further, the distance TA from the rotary shaft 17 to each of the first, second, third and fourth sides 12, 13, 14 and 15₀, TB₀, TA₉₀And TB₉₀Are measured, and based on these, the Y-axis direction address TC + TA of the first side 12 when it is in the original position₀And the Y-axis direction address TC-TB of the second side 13₀, And the Y-axis direction address TC + TA of the third side 14 after the forward rotation₉₀And the Y-axis direction address TC-TB of the fourth side 15₉₀Is required.
[0042]
Depending on the assembling accuracy of the cutting device and the processing accuracy of components provided in the cutting device, the rotating shaft 17 may not pass through the exact center position of the mounting surface 16. In this case, the deviation amounts of the first to fourth sides 12 to 15 at the original position and the position after the forward rotation are measured in advance, and these deviation amounts are taken into account when determining the address described above. It is preferable to do.
[0043]
As shown in FIG. 3 and FIG. 4, the cutting device is a pair of cameras capable of imaging in a direction from the position outside the table 11 toward the two opposite sides 12 and 13 or 14 and 15 of the mounting surface 16. Cameras 18 and 19 are provided. Each of these cameras 18 and 19 can be changed in distance to the table 11 for focusing. The movement of each of the cameras 18 and 19 for focusing is driven and controlled by, for example, a servo motor or a stepping motor.
[0044]
Further, for the cameras 18 and 19, the following addresses are obtained in advance based on actual measurements and stored.
[0045]
That is, as shown in FIG. 3, the X-axis direction address CB of the camera 19 focused on the third side 14 of the mounting surface 16 when in the original position.₀And the X-axis direction address CA of the camera 18 focused with respect to the fourth side 15₀Is required.
[0046]
On the other hand, as shown in FIG. 4, the X-axis direction address CA of the camera 18 focused on the first side 12 of the mounting surface 16 after rotating in the forward direction.₉₀And the X-axis direction address CB of the camera 19 focused with respect to the second side 13₉₀Is required.
[0047]
For these addresses, for example, a block gauge or the like (not shown) is installed on each of the sides 12 to 15 to focus the cameras 18 and 19, and the positions of the cameras 18 and 19 at this time are measured. It is required by doing.
[0048]
In determining the addresses of the cameras 18 and 19, the positional deviation from the center of the rotation shaft 17 as described above may be taken into consideration.
[0049]
The cutting device includes a cutting mechanism for cutting a ceramic green sheet laminate 21 described later with reference to FIGS. 5 to 7 with a cutting surface extending linearly. As for the cutting mechanism, the drawing only shows a position to be cut by the cutting mechanism or a cut surface obtained by the cutting, and the specific structure is not shown. As a cutting mechanism, as is well known, for example, a cutting mechanism that performs cutting by push-cutting by moving a linear cutting blade up and down can be used. Alternatively, a cutting mechanism using a laser or a water jet is used even if a cutting mechanism that performs cutting by rotating a disc-shaped cutting blade or a dicing type cutting mechanism that rotates by cutting a dicing saw is used. May be. In short, any cutting mechanism may be used as long as the cut surface formed by cutting extends linearly.
[0050]
With reference to FIG. 5 thru | or FIG. 7, an example of the ceramic green sheet laminated body which should be cut | disconnected is demonstrated. FIG. 5 is a plan view showing one ceramic green sheet 22 constituting the ceramic green sheet laminate. 6 and 7 show a ceramic green sheet laminate 21 obtained by laminating a plurality of ceramic green sheets including the ceramic green sheet 22.
[0051]
6 and 7, only representative ceramic green sheets 22 constituting the ceramic green sheet laminate 21 are illustrated, and for example, the ceramic green sheets positioned at both ends in the stacking direction are not illustrated. . 6 and 7 illustrate the ceramic green sheets 22 separated from each other by the thickness of the internal electrodes 23 so that the positional relationship of the internal electrodes 23 in the stacking direction can be easily understood. Yes.
[0052]
6 shows the ceramic green sheet laminate 21 from the lower end face direction of the ceramic green sheet 22 in FIG. 5, and FIG. 7 shows the ceramic green sheet 22 from the right end face direction in FIG. It is the figure which showed the green sheet laminated body.
[0053]
As shown in FIG. 5, a plurality of internal electrodes 23 are formed on a ceramic green sheet 22 so as to be distributed at a plurality of locations. In this embodiment, the ceramic green sheet laminate 21 is for obtaining a multilayer ceramic capacitor, and the internal electrode 23 is for forming a capacitance.
[0054]
A plurality of sensing marks 24 are formed on the ceramic green sheet 22 along two opposite sides.
[0055]
The internal electrode 23 and the sensing mark 24 described above are formed by, for example, a screen printing method, a gravure printing method, or an ink jet method. Alternatively, the internal electrode 23 and the sensing mark 24 may be formed by a thin film forming method such as PVD or CVD.
[0056]
As shown in FIG. 6, the plurality of ceramic green sheets 22 are stacked such that the internal electrodes 23 are alternately displaced in the stacking direction, and then pressed in the stacking direction, whereby the ceramic green sheet stack 21 is obtained. . The ceramic green sheet laminate 21 is cut at the cutting position 25 shown in FIG. 6 and the cutting position 26 shown in FIG. 7, whereby chips that are component bodies for the plurality of multilayer ceramic capacitors are taken out.
[0057]
As shown in FIGS. 6 and 7, the ceramic green sheet laminate 21 has a planar rectangular shape having first and second end faces 27 and 28 facing each other and third and fourth end faces 29 and 30 facing each other. belongs to. As described above, the third and fourth end faces 29 and 30 are formed by shifting the ceramic green sheets 22 and thus forming irregular surfaces as shown in FIG. For the convenience of explanation, these irregular surfaces will be referred to as end surfaces as a whole. Further, in order to easily understand the correspondence between FIG. 5 and FIGS. 6 and 7, the ceramic green sheets 22 to be provided with the first to fourth end faces 27 to 30 of the ceramic green sheet laminate 21, respectively. Corresponding reference numerals “27” to “30” are also attached to the end faces as shown in FIG.
[0058]
As can be seen from FIG. 5, the sensing mark 24 is attached to each position along the first and second end faces 27 and 28 of the ceramic green sheet laminate 21.
[0059]
It is preferable that the ceramic green sheet laminate 21 is preliminarily aligned using an alignment table 31 as shown in FIG. 8 in the previous stage of cutting using the above-described cutting apparatus. The alignment table 31 is for aligning the ceramic green sheet laminate 21 based on the outer shape reference.
[0060]
The alignment table 31 has a quadrangular planar shape, and fixed guides 32 and 33 are fixedly provided along two adjacent sides. In addition, movable guides 34 and 35 are provided so as to face the fixed guides 32 and 33, respectively. The movable guides 34 and 35 can be moved toward and away from the fixed guides 32 and 33, respectively.
[0061]
First, as shown by a broken line in FIG. 8, the ceramic green sheet laminate 21 is placed on the alignment table 31 relatively randomly. The movable guides 34 and 35 are then moved toward the fixed guides 32 and 33 as indicated by arrows 36 and 37, respectively. In the middle of this movement, the movable guides 34 and 35 push and move the ceramic green sheet laminate 21. As a result, the ceramic green sheet laminate 21 is aligned with the fixed guides 32 and 33 as shown by the solid line in FIG.
[0062]
Thus, the ceramic green sheet laminated body 21 aligned on the alignment table 31 is conveyed by, for example, a vacuum suction chuck, and as shown in FIG. 9, on the mounting surface 16 of the table 12 included in the cutting apparatus. Placed. If the ceramic green sheet laminate 21 is placed on the placement surface 16 in this manner, the rough alignment of the ceramic green sheet laminate 21 on the placement surface 16 is easily and efficiently performed. be able to.
[0063]
Although not shown, the table 11 includes a large number of suction ports for applying a negative pressure on the mounting surface 16, and the ceramic green sheet laminate 21 is sucked and fixed onto the mounting surface 16. . Further, a breathable sheet is preferably disposed between the ceramic green sheet laminate 21 and the mounting surface 16, and negative pressure from the suction port is applied to the ceramic green sheet laminate 21 through the breathable sheet. Affected. The table 11 preferably includes a heater. As a result, the ceramic green sheet laminate 21 is heated to a certain temperature and can be cut more easily.
[0064]
In the ceramic green sheet laminate 21 shown in FIGS. 9 to 12, an internal electrode 23 and a sensing mark 24 are also shown. The internal electrode 23 and the sensing mark 24 are present inside the ceramic green sheet laminate 21 and are not actually visible from above, but are shown for convenience of explanation. Further, the internal electrode 23 is omitted from illustration by showing the formation region 38 with a broken line.
[0065]
As a result of the placing step of placing the ceramic green sheet laminate 21 on the placement surface 16, the first and second end faces 27 and 28 of the ceramic green sheet laminate 21 are placed as shown in FIG. It arrange | positions so that it may extend in the direction parallel to the 1st and 2nd edge | sides 12 and 13 of the surface 16, respectively.
[0066]
Next, a preliminary cutting step is performed in which the ceramic green sheet laminate 21 is cut in the vicinity of the first and second end faces 27 and 28 by the cutting mechanism. The cutting positions 39 and 40 at this time are indicated by a one-dot chain line in FIG. The Y-axis direction addresses A1 and A2 of the cutting positions 39 and 40 are obtained from the relative positional relationship between the table 11 and the cutting mechanism and stored.
[0067]
  Preliminary cut surface at the cutting positions 39 and 40 formed by the above precutting step4110 and FIG. 10, the sensing mark 24 is exposed on the preliminary cut surfaces 41 and 42. In this case, the sensing mark 24 can be reliably exposed on the preliminary cut surfaces 41 and 42 regardless of the alignment error of the ceramic green sheet laminate 21 on the mounting surface 16 in the mounting step described above. Is preferred. Therefore, the sensing mark 24 has a shape extending relatively long in the vertical direction with respect to the first and second end faces 27 and 28 of the ceramic green sheet laminate 21 as illustrated. As an example, the length of the sensing mark 24 is about 2 to 5 mm.
[0068]
As described above, after the opposing pre-cut surfaces 41 and 42 are formed, portions outside these pre-cut surfaces are removed using a method such as manual, suction or adhesion.
[0069]
Next, a forward direction rotation process is performed in which the table 11 is rotated 90 degrees in the forward direction from the original position shown in FIG. As a result, the table 11 is in the state shown in FIG. As a result of this forward rotation process, for example, even if there is an angle error of 1 degree or less, since the cameras 18 and 19 are on both sides of the ceramic green sheet laminate 21, the error can be detected and corrected.
[0070]
In the stage shown in FIG. 10, in order to focus each of the cameras 18 and 19 on the pre-cut surfaces 41 and 42 of the ceramic green sheet laminate 21 before entering the next step, shown by a broken line and a solid line in FIG. Thus, the cameras 18 and 19 are moved.
[0071]
The movement amount of each of the cameras 18 and 19 is obtained in advance as described above, the Y-axis direction address TC of the rotating shaft 17 shown in FIGS. 1 and 2, and the load when the camera 18 and 19 are at the original position shown in FIG. Y-axis direction address TC + TA of the first side 12 of the mounting surface 16₀And the Y-axis direction address TC-TB of the second side 13₀And the X-axis direction address CA of the camera 18 focused on the first side 12 of the mounting surface 16 after the forward rotation shown in FIG.₉₀And the X-axis direction address CB of the camera 19 focused with respect to the second side 13₉₀9 and the cutting position 39 to be cut in the preliminary cutting step, that is, the Y-axis direction address A1 of the preliminary cutting surface 41, and the cutting position 40, that is, the Y-axis direction address A2 of the preliminary cutting surface 42. It is done.
[0072]
More specifically, for the camera 18, the CA₉₀− | TA₀-(| TC-A1 |) | is moved to the position of the address in the X-axis direction.₉₀+ | TB₀-(| TC-A2 |) | is moved to the position of the address in the X-axis direction. As a result, the cameras 18 and 19 are focused on the preliminary cutting surfaces 41 and 42, respectively.
[0073]
Next, the cutting mechanism repeats cutting the ceramic green sheet laminate 21 at the cutting position 25 (also shown in FIG. 6) and moving the table 11 a plurality of times as shown in FIG. A primary cutting step is performed. As a result of the cutting at the cutting position 25 performed in the primary cutting step, the ceramic green sheet laminate 21 is arranged in the extending direction of the preliminary cutting surfaces 41 and 42 as shown in FIG. A state of being cut along a plurality of primary cut surfaces 43 extending in a direction orthogonal to the preliminary cut surfaces 41 and 42, that is, a strip shape.
[0074]
The cutting position 25 in the primary cutting process is determined by processing images obtained by imaging the preliminary cutting surfaces 41 and 42 with the cameras 18 and 19. In this embodiment, the cameras 18 and 19 are scanned so that the sensing mark 24 exposed on the preliminary cutting surfaces 41 and 42 is imaged, and the Y-axis direction address of the cutting position 25 is stored. At this time, rotation direction correction may be applied based on the difference in the imaging position of the sensing mark 24 between the cameras 18 and 19.
[0075]
  In determining the cutting position 25, in this embodiment, the cutting position 25 comes to the center position of the sensing mark 24, but the cutting position 25 comes to the center position between two adjacent sensing marks 24. May be. Further, in consideration of the positional deviation of the ceramic green sheet laminate 21 that may occur according to the progress of cutting, the cutting position 25 is equally divided by the number of cuttings between the first and last cutting positions 25, 25 may be determined.
[0076]
In processing images picked up by the cameras 18 and 19, for example, a binarized image processing method or a pattern matching method can be applied.
[0077]
Further, in order to ensure scanning of the cameras 18 and 19, a conspicuous mark may be arranged outside the area where the sensing marks 24 are arranged.
[0078]
In the primary cutting step shown in FIG. 11, Y-axis direction addresses B1 and B2 of those located at both ends of the plurality of cutting positions 25 (primary cutting surfaces 43) are stored.
[0079]
Further, when the primary cutting process is finished, the outer portions of the plurality of cutting positions 25, that is, the primary cutting surfaces 43 that are located at both ends are, for example, manually, sucked, or bonded as shown in FIG. Removed.
[0080]
Next, a reverse rotation process in which the table 11 is rotated 90 degrees in the reverse direction (counterclockwise) so as to return to the original position shown in FIG. 12 from the position after the forward rotation shown in FIG. Is implemented.
[0081]
Next, the ceramic green sheet laminate 21 is cut at a cutting position 26 (also shown in FIG. 7) extending in a direction perpendicular to the primary cutting surface 43 while being arranged in the extending direction of the primary cutting surface 43. A secondary cutting step is performed in which cutting along the secondary cutting plane and moving the table 11 are repeated a plurality of times. As a result, the ceramic green sheet laminate 21 cut into strips in the primary cutting step as described above is cut into chips so as to provide a component body for each multilayer ceramic capacitor.
[0082]
The cutting position 26 is determined by processing images obtained by taking images of the primary cutting planes 43 obtained at the both ends of the plurality of primary cutting surfaces 43 obtained by the above-described primary cutting process with the cameras 18 and 19. The As can be seen from the position passing through the cutting position 25 shown in FIG. 6, since the specific internal electrode 23 is exposed on the primary cutting surface 43 at the cutting position 25, in the secondary cutting step, The internal electrode 23 is imaged by the camera, and image processing is performed in the same manner as in the above-described primary cutting step.
[0083]
Also, in order to perform the secondary cutting process, the cameras 18 and 19 are moved so as to be brought to positions focused on the primary cutting surfaces 43 at both ends. This movement amount is determined by the Y-axis direction address TC of the rotating shaft 17 shown in FIGS. 1 and 2, and the Y-axis direction address TC + TA of the third side 14 of the mounting surface 16 after the forward rotation shown in FIG.₉₀And the Y-axis direction address TC-TB of the fourth side 15₉₀And the X-axis direction address CB of the camera 19 focused on the third side 14 of the mounting surface 16 at the original position shown in FIG.₀And the X-axis direction address CA of the camera 18 focused with respect to the fourth side 15₀And the arithmetic processing using the Y-axis direction addresses B1 and B2 of the primary cutting surfaces 43 (cutting positions 25) at both ends obtained by the primary cutting step shown in FIG.
[0084]
More specifically, for the camera 18, the CA₀− | TB₉₀-(| TC-B2 |) | is moved to the position of the address in the X-axis direction.₀+ | TA₉₀-(| TC-B1 |) | is moved to the position of the address in the X-axis direction.
[0085]
Also in the secondary cutting step, the rotational direction correction may be applied based on the difference in the imaging position of the internal electrode 23 between the cameras 18 and 19.
[0086]
As described above, according to this embodiment, the cameras 18 and 19 are brought into the focused positions in both the primary cutting process and the secondary cutting process by the arithmetic processing using the address obtained in advance. Can be moved immediately.
[0087]
FIG. 13 is a view corresponding to FIG. 5 for explaining another embodiment of the present invention. In FIG. 13, elements corresponding to the elements shown in FIG. 5 are denoted by the same reference numerals, and redundant description is omitted.
[0088]
In the ceramic green sheet 22a shown in FIG. 13, sensing marks 24a are also formed in regions corresponding to the regions along the third and fourth end surfaces 29 and 30 of the ceramic green sheet laminate. The second sensing mark 24a is exposed on the primary cut surface 43 (see FIG. 12) formed in the primary cutting step. Therefore, in the secondary cutting step, the second sensing mark 24a is second by the cameras 18 and 19. The sensing mark 24a is captured and used to determine the cutting position 26 (see FIG. 12) in the secondary cutting process.
[0089]
The present invention has been described above in relation to the ceramic green sheet laminate 21 for taking out the component main body of the multilayer ceramic capacitor. However, the present invention is not limited to the multilayer ceramic capacitor, and the component main body of other multilayer ceramic electronic components. The present invention can also be applied to the cutting of a ceramic green sheet laminate for taking out.
[0090]
【The invention's effect】
As described above, according to the present invention, since the position for focusing the camera is obtained from the various addresses obtained in advance by the arithmetic processing, the camera can be brought quickly to the focused position. it can. Therefore, it is not necessary to use a camera equipped with an automatic focusing function, the equipment cost can be kept low, and the focusing reliability is easily achieved even when the thickness of the ceramic green sheet laminate to be cut is reduced. Can be secured.
[0091]
  Also,After placing the laminated green sheet on the table mounting surface, a preliminary cutting process is performed.In advanceCut surfaceForming this pre-cut surfaceAddressIs determined in advance, and the address of the preliminary cut surface determined in advance is used for camera focusing.Since it is used, at the stage where the ceramic green sheet laminate is placed on the mounting surface, so high accuracy is not required. For this reason, a guide for aligning the ceramic green sheet laminate at a predetermined position on the placement surface is not particularly required. Therefore, even if the thickness of the ceramic green sheet laminate is reduced, it is possible to avoid problems such as floating and sinking under the guide, and it is possible to provide a cutting device at a low cost.
[0092]
  Also,In this inventionAccording toAs the ceramic green laminate, one having a sensing mark attached to each region along the first and second end faces facing each other is prepared, so that the preliminary cutting step exposes the sensing mark on the preliminary cutting surface. The sensing mark is picked up by the camera in the primary cutting process.BecauseRegardless of the formation state of the internal electrode, the cutting position in the primary cutting step can be determined reliably.
[0093]
  Furthermore, according to the present invention,The above-described sensing mark has a length that can be exposed on the preliminary cutting surface formed in the preliminary cutting step regardless of the alignment error of the ceramic green sheet laminate on the mounting surface in the mounting step. It has a shape extending in a direction perpendicular to the second end faceBecauseIn the mounting process, it is possible to prevent the high accuracy of the ceramic green sheet laminated body from being aligned.
[0094]
  In this inventionAs a ceramic green sheet laminate, a sensing mark is provided in each region along the third and fourth end faces facing each other.furtherWhen the attached mark is prepared, the primary cutting process is performed so that the sensing mark is exposed on the primary cutting surface, and the sensing mark is imaged by the camera in the secondary cutting process, Regardless of the formation state of the internal electrode, the cutting position in the secondary cutting process can be determined reliably.
[0095]
In the present invention, an alignment stand for aligning the ceramic green sheets according to the outer shape reference is used, the ceramic green sheet laminate is aligned on the alignment stand, and the aligned ceramic green sheet laminate is conveyed. If it is placed on the mounting surface, the rough alignment of the ceramic green sheet laminate on the mounting surface can be easily and efficiently performed.
[Brief description of the drawings]
FIG. 1 is a plan view showing a table 11 provided in a cutting device used for carrying out a cutting method according to an embodiment of the present invention, together with coordinate axes for displaying addresses, in a state where the table 11 is in its original position. Show.
2 is a view corresponding to FIG. 1, showing a state after the table 11 shown in FIG. 1 is rotated in the forward direction.
FIG. 3 is a plan view showing the table 11 and cameras 18 and 19 included in the cutting apparatus together with coordinate axes for displaying addresses, and shows a state in which the table 11 is in its original position.
4 is a view corresponding to FIG. 3, showing a state after the table 11 shown in FIG. 3 is rotated in the forward direction.
FIG. 5 is a plan view showing one ceramic green sheet 22 constituting the ceramic green sheet laminate 21. FIG.
6 is a diagram showing a ceramic green sheet laminated body 21 obtained by laminating a plurality of ceramic green sheets including the ceramic green sheet 22 shown in FIG. 5, as viewed from the lower side of FIG.
7 is a view showing the ceramic green sheet laminate 21 shown in FIG. 6 from the right side of FIG. 5;
FIG. 8 is a plan view showing an alignment table 31 used for roughly aligning the ceramic green sheet laminate 21. FIG.
FIG. 9 is a plan view showing a placing process and a preliminary cutting process provided for a cutting method performed using the cutting apparatus described with reference to FIGS. 1 to 4;
10 is a view corresponding to FIG. 9 for explaining the forward direction rotation process and focusing of the cameras 18 and 19. FIG.
FIG. 11 is a view corresponding to FIG. 9 and FIG. 10 for explaining the primary cutting step.
FIG. 12 is a view corresponding to FIGS. 9 to 11 for explaining the reverse rotation process and the secondary cutting process.
FIG. 13 is a view corresponding to FIG. 5 for explaining another embodiment of the present invention.
FIG. 14 is a front view showing a ceramic green sheet laminate 4 aligned by a guide 3 on a mounting surface 2 for explaining a problem to be solved by the present invention.
FIG. 15 is a diagram corresponding to FIG. 14 for explaining another problem to be solved by the present invention.
[Explanation of symbols]
11 tables
12 First side
13 Second side
14 Third side
15 4th side
16 Placement surface
17 Rotating shaft
18, 19 camera
21 Ceramic green sheet laminate
22, 22a Ceramic green sheet
23 Internal electrode
24, 24a Sensing mark
25, 26, 39, 40 Cutting position
27 First end face
28 Second end face
29 Third end face
30 Fourth end face
31 Alignment stand
41, 42 Preliminary cut surface
43 Primary cut surface
TC Y-axis direction address of rotary shaft 17
TC + TA₀  Y-axis direction address of the first side 12 of the mounting surface 16 when in the original position
TC-TB₀  Y-axis direction address of the second side 13 of the mounting surface 16 when in the original position
TC + TA₉₀  Y-axis direction address of the third side 14 of the mounting surface 16 after rotation in the forward direction
TC-TB₉₀  Y-axis direction address of the fourth side 15 of the mounting surface 16 after rotation in the forward direction
CA₀  X-axis direction address of the camera 18 focused on the fourth side 15 of the mounting surface 16 when in the original position
CB₀  X-axis direction address of the camera 19 focused on the third side 14 of the mounting surface 16 when in the original position
CA₉₀  X-axis direction address of the camera 18 focused on the first side 12 of the mounting surface 16 after rotating in the forward direction
CB₉₀  X-axis direction address of the camera 19 focused on the second side 13 of the mounting surface 16 after rotating in the forward direction
A1, A2 Y-axis direction address of pre-cut surfaces 41, 42
B1, B2 Y-axis direction address of primary cut surface 43 at both ends

Claims (3)

Forming a rectangular mounting surface for placing a ceramic green sheet laminate to be cut, having first and second sides facing each other and third and fourth sides facing each other And a table that is rotatable about a predetermined rotation axis that passes in a direction orthogonal to the center of the mounting surface,
A cutting mechanism for cutting the ceramic green sheet laminate placed on the placement surface of the table with a cutting surface extending linearly;
At least one pair of cameras capable of imaging in directions directed from two positions toward the opposite sides of the mounting surface from a position outside the table and capable of changing a distance from the table for focusing. And
The table is movable relative to the cutting mechanism and the camera in the direction in which the placement surface extends,
The cutting operation by the cutting mechanism and the relative movement of the table are repeated a plurality of times at each position to be cut of the ceramic green sheet laminate determined by processing an image picked up by the camera. By the cutting method of the ceramic green sheet laminate, the ceramic green sheet laminate is implemented using a cutting device configured to be cut along cut surfaces arranged in a predetermined direction. There,
The ceramic green sheet laminate is a planar quadrangular shape having first and second end faces facing each other and third and fourth end faces facing each other, along the first and second end faces. Each area has a sensing mark attached .
The ceramic green sheet laminate is described above such that the first and second end faces of the ceramic green sheet laminate extend in directions parallel to the first and second sides of the placement surface, respectively. Placing on the mounting surface, and
Next, the ceramic green sheet laminate is cut in the vicinity of the first and second end faces by the cutting mechanism, thereby forming opposing preliminary cut faces and the sensing marks on the preliminary cut faces. And a preliminary cutting step of removing a portion outside the preliminary cutting surface,
Next, a forward direction rotation step of rotating the table around the rotational axis by 90 degrees in the forward direction from the original position;
Next, at each position to be cut of the ceramic green sheet laminate determined by processing an image obtained by imaging the sensing mark exposed on the preliminary cut surface with the camera, the cutting mechanism The ceramic green sheet laminate is primary cut extending in a direction orthogonal to the preliminary cutting surface while being arranged in the extending direction of the preliminary cutting surface by repeating the cutting operation by the step and the relative movement of the table a plurality of times. A primary cutting step of cutting along the surface and removing portions outside the ones at both ends of the plurality of primary cutting surfaces;
Next, a reverse rotation step of rotating the table around the rotation axis by 90 degrees in the reverse direction and returning the table to the original position;
Next, the ceramic green sheet determined by processing images obtained by imaging the ones located at both ends of the plurality of primary cut surfaces obtained by the primary cutting step with the camera The ceramic green sheet laminate is arranged in the extending direction of the primary cut surface by repeating the cutting operation by the cutting mechanism and the relative movement of the table a plurality of times at each position to be cut of the laminate. And a secondary cutting step of cutting along a secondary cutting surface extending in a direction orthogonal to the primary cutting surface,
The sensing mark has a length that can be exposed on the preliminary cutting surface formed in the preliminary cutting step regardless of the alignment error of the ceramic green sheet laminate on the mounting surface in the previous mounting step. , Having a shape extending in a direction perpendicular to the first and second end faces,
The address of the rotation axis, each address of the first and second sides of the placement surface when in the original position, and the third and fourth of the placement surface after the forward rotation Each address of the side, each address of the camera focused on each of the third and fourth sides of the placement surface when in the original position, and the previous description after the forward rotation Each address of the camera focused on each of the first and second sides of the placement surface, each address of the preliminary cut surface obtained by the preliminary cutting step, and the primary cutting step the resulting said primary cutting surface each address of both ends, further comprising the step of Ru determined in advance based on actual measurement,
In order to carry out the primary cutting step, the camera rotates the address of the rotation axis, the addresses of the first and second sides of the placement surface when in the original position, and the forward rotation. Obtained by calculation processing using each address of the camera focused on each of the first and second sides of the placement surface described later and each address of the preliminary cut surface obtained in advance. Brought into a position focused on the preliminary cut surface,
In order to perform the secondary cutting step, the camera is in the original position and the address of the rotation axis, the addresses of the third and fourth sides of the placement surface after the forward rotation, and the original position. When calculation processing using each address of the camera focused on each of the third and fourth sides of the placement surface and the respective addresses of the primary cut surface obtained in advance is performed Brought to the determined position focused on the primary cutting surface at both ends,
Cutting method of ceramic green sheet laminate . The ceramic green sheet laminate is prepared by further adding a second sensing mark to each region along the third and fourth end faces, and the primary cutting step includes the second sensing mark. It is performed to expose on the primary cutting surface of both ends, wherein in the second cutting step, the sensing mark by the camera is captured, the ceramic green sheet laminate cutting method according to claim 1. A step of preparing an alignment table for aligning the ceramic green sheet laminate on the basis of an external shape; and a step of aligning the ceramic green sheet laminate on the alignment table. comprises the steps of placing on a mounting surface before conveying the aligned said ceramic green sheet laminate on said alignment table, the ceramic green sheet laminate cutting method according to claim 1 or 2.

Images