JP2004174917A - Cutting method for ceramic green molded body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a positional slippage becomes larger on one end side of a ceramic green molded body as cutting of this body proceeds, when the body is cut sequentially from the other end side thereof by pressing down a cutting edge. <P>SOLUTION: Cutting by the cutting edge 6 is started from one end side of the ceramic green molded body 1, and in the course thereof, the cutting is shifted once at least so as to be conducted from the other end side of the body 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for cutting a ceramic green molded body, and more particularly to a method for cutting a ceramic green molded body, the method including a step of sequentially cutting the ceramic green molded body from one end side by pushing and cutting with a cutting blade. .
[0002]
[Prior art]
For example, in order to efficiently mass-produce ceramic electronic components such as a multilayer ceramic capacitor, a ceramic green molded body from which a plurality of ceramic electronic components are to be taken out is first manufactured. Amputation of the body is performed. For example, when a multilayer ceramic electronic component such as a multilayer ceramic capacitor is to be manufactured, the ceramic green molded body includes a multilayer body of a plurality of ceramic green sheets having an internal conductor film formed along a specific interface. Is done.
[0003]
The above-described cutting step of the ceramic green molded body is usually performed as follows.
[0004]
FIG. 5 is a perspective view showing a state in which a step of cutting the ceramic green compact 1 is being performed (for example, see Patent Document 1).
[0005]
The ceramic green compact 1 having the main surfaces 2 and 3 facing each other is fixed on a table 4 by suction. More specifically, although not shown, the table 4 is provided with a number of suction ports for applying a negative pressure to the ceramic green molded body 1, and the negative pressure is applied to the ceramic green molded body 1 and the table 4. Through the air-permeable sheet 5 disposed between the ceramic green molded bodies 1.
[0006]
On the other hand, the cutting blade 6 is arranged so as to face the table 4 with the ceramic green compact 1 interposed therebetween. The cutting blade 6 is configured to be able to reciprocate in each of the descending and ascending directions. By lowering the cutting blade 6 toward the main surface 2 of the ceramic green molded body 1, the ceramic green molded body 1 is cut by push cutting.
[0007]
The table 4 and the cutting blade 6 are configured to be relatively movable. In this case, the position of the cutting blade 6 is fixed and the table 4 is often movable. However, instead of this, the position of the table 4 is fixed and the cutting blade 6 is configured to be movable. Alternatively, both the table 4 and the cutting blade 6 may be configured to be movable.
[0008]
By repeating the above-described cutting step by the cutting blade 6 and the step of moving the table 4 and the cutting blade 6 relative to each other a plurality of times, the cutting proceeds, for example, in the direction indicated by the arrow 7, and the ceramic green molded body 1 The cutting is performed along a plurality of cutting lines 8 arranged in the main surface 2 direction.
[0009]
After the cutting progressing in the direction of arrow 7 is completed by repeating the above-described cutting step and moving step, usually, the table 4 and the cutting blade 6 are relatively rotated by 90 degrees. The moving process is repeated.
[0010]
[Patent Document 1]
JP 2002-134356 A [Patent Document 2]
JP-A-11-90894
[Problems to be solved by the invention]
However, the cutting method shown in FIG. 5 has the following problems.
[0012]
FIG. 6 is a cross-sectional view for explaining a problem that may occur in the cutting method shown in FIG.
[0013]
Referring to FIG. 6, since cutting blade 6 has a constant thickness, when cutting blade 6 enters ceramic green compact 1, it will be pushed and spread to both sides as shown by arrows 9 and 10. The power to work. As described above, if the force for suction-fixing the ceramic green molded body 1 on the table 4 (see FIG. 5) is sufficient, the force exerted on the ceramic green molded body 1 by the penetration of the cutting blade 6 is as follows. It is absorbed by elastic deformation or plastic deformation of the ceramic green molded body 1, and the ceramic green molded body 1 does not shift on the table 4.
[0014]
However, as the cutting progresses and the remaining portion 11 of the ceramic green molded body 1 to be cut becomes smaller, the weight of the remaining portion 11 becomes smaller and the area to which the negative pressure from the table 4 is exerted is reduced. The force of the suction fixation becomes smaller as a result. Therefore, as a result of the force in the direction of arrow 9 exerted by the entry of the cutting blade 6, a displacement 12 occurs in the ceramic green molded body 1, and the cutting position by the cutting blade 6 is shifted from a desired position due to the displacement 12. It may shift.
[0015]
In order to solve such a problem, it is effective to position the ceramic green compact 1 by applying a guide 13 to one end face of the ceramic green compact 1 as shown in FIG. Reference 2).
[0016]
However, when the guide 13 shown in FIG. 7 is applied, the force in the direction of the arrow 9 due to the entry of the cutting blade 6 shown in FIG. 7 may be deformed by lifting or the like as shown by an arrow 14 in FIG. Such deformation such as lifting is particularly likely to occur when the thickness of the ceramic green compact 1 is small.
[0017]
At present, ceramic electronic components are becoming thinner, and as a result, the thickness of the ceramic green compact 1 tends to be smaller. Therefore, there is a demand that the method of using the guide 13 to prevent the above-described positional displacement be avoided as much as possible.
[0018]
Therefore, an object of the present invention is to provide a method for cutting a ceramic green molded body that can eliminate the problem of misalignment during cutting without using a guide.
[0019]
[Means for Solving the Problems]
The present invention provides a step of suction-fixing a ceramic green molded body having opposing main surfaces on a table, and pushing down the ceramic green molded body by lowering a cutting blade toward the main surface of the ceramic green molded body. Cutting, and a step of relatively moving the table and the cutting blade, by repeating the cutting step and the moving step a plurality of times, the ceramic green compacts are arranged in the main surface direction. It is directed to a method for cutting a ceramic green molded body, in a state of being cut along a plurality of cutting lines, in order to solve the above-described technical problem, characterized by having the following configuration I have.
[0020]
That is, in the method for cutting a ceramic green molded body according to the present invention, the cutting step and the moving step are repeated a plurality of times, thereby cutting the ceramic green molded body from one end side, and in the middle of the cutting, The method further comprises a step of switching at least once so as to cut from the other end side of the molded body.
[0021]
The timing at which the above-described switching step is performed may be determined in advance, or may be performed by repeating the cutting step and the moving step a plurality of times, while sensing the positional deviation of the ceramic green compact to be cut, and performing the sensing. It may be a point in time when the amount of misalignment exceeds a predetermined threshold value.
[0022]
As in the former case, when the timing of performing the switching step is predetermined, the cutting line formed by cutting from one end side of the ceramic green compact by repeating the cutting step and the moving step a plurality of times. Is preferably at the time when the number reaches 20 to 80% of the total number of cutting lines to be formed in the ceramic green molded body.
[0023]
INDUSTRIAL APPLICABILITY The present invention is advantageously applied when manufacturing multilayer ceramic electronic components such as multilayer ceramic capacitors, multilayer inductors, multilayer noise filters, and multilayer composite components. In this case, the ceramic green compact is a laminate of a plurality of ceramic green sheets on which an internal conductor film is formed along a specific interface.
[0024]
After the cutting step and the moving step as described above are completed, the table and the cutting blade are relatively rotated by 90 degrees, and then the cutting step and the moving step involving the same switching step are repeated. You may.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a view for explaining a method for cutting a ceramic green molded body according to an embodiment of the present invention, and sequentially shows some typical steps included in the cutting method. FIG. 2 shows a state in which the ceramic green molded body 1 is suction-fixed on the table 4. In FIGS. 1 and 2, elements corresponding to the elements shown in FIG. 5 are denoted by the same reference numerals.
[0026]
First, referring to FIG. 2, ceramic green compact 1 having opposing main surfaces 2 and 3 is suction-fixed on table 4. The table 4 is provided with a number of suction ports (not shown) for applying a negative pressure to the ceramic green compact 1 as shown by an arrow 21. A gas permeable sheet 5 is arranged between the ceramic green compact 1 and the table 4, and a negative pressure 21 from the table 4 is applied to the ceramic green compact 1 through the gas permeable sheet 5. The permeable sheet 5 is made of, for example, paper or a permeable resin sheet.
[0027]
It is preferable that the table 4 has a built-in heater (not shown). This heater acts to heat the ceramic green compact 1 to a certain temperature, thereby reducing the resistance at the time of cutting by the cutting blade 6 described later and preventing the cutting blade 6 from being chipped or cracked. .
[0028]
Next, referring to FIG. 1, a cutting blade 6 is arranged so as to face table 4 with ceramic green compact 1 interposed therebetween. The cutting blade 6 is configured to be able to move in each of the downward and upward directions. When the cutting blade 6 descends toward the main surface 2 of the ceramic green molded body 1, the ceramic green molded body 1 is cut by push cutting, and a cutting line 8 is formed there.
[0029]
When the cutting blade 6 descends, the cutting blade 6 penetrates the ceramic green molded body 1 in the thickness direction, and in the middle of the thickness direction of the gas permeable sheet 5 (for example, 1/3 to 1 of the thickness of the gas permeable sheet 5). / 2) is preferably controlled so as to insert the cutting edge. Thereby, not only can the ceramic green compact 1 be completely cut, but also the cutting edge of the cutting blade 6 can be prevented from being damaged by contact with the table 4.
[0030]
The table 4 and the cutting blade 6 are configured to be relatively movable. In this case, the position of the cutting blade 6 is often fixed and the position of the table 4 is movable. Instead, the position of the table 4 is fixed and the position of the cutting blade 6 is movable. It may be configured, or may be configured such that the positions of both the table 4 and the cutting blade 6 are movable. In the following description, the position of the cutting blade 6 is fixed and the position of the table 4 is movable.
[0031]
The movement of the table 4 is configured to occur in conjunction with the reciprocating movement of the cutting blade 6 in each of the downward and upward directions. That is, after each of the lowering and raising operations of the cutting blade 6 is completed once, the table 4 is moved at a predetermined pitch. By repeating the cutting step by lowering the cutting blade 6 and the moving step of the table 4 a plurality of times, the ceramic green compact 1 is moved along the plurality of cutting lines 8 arranged in the direction of the main surface 2. It will be in a disconnected state.
[0032]
This embodiment is characterized in that the above-described cutting step and moving step are performed as follows.
[0033]
First, as shown in FIG. 1A, the cutting of the ceramic green compact 1 by the cutting blade 6 is started from one end of the ceramic green compact 1 while the table 4 is moved in the direction of the arrow 22. The traveling direction of the cutting at this time is indicated by an arrow 23. The cutting that proceeds in the direction of arrow 23 in this manner is not performed to the other end of the ceramic green compact 1, but is interrupted halfway, and the table 4 is moved in the direction of arrow 22 with the cutting blade 6 raised. Moved to
[0034]
Next, as shown in FIG. 1 (2), while the table 4 is moved in the direction of the arrow 24, the cutting by the cutting blade 6 is started again from the other end of the ceramic green compact 1 and cut in the direction shown by the arrow 25. Are switched to proceed.
[0035]
As described above, by repeating the cutting step and the moving step a plurality of times, first, as shown in FIG. 1A, the ceramic green molded body 1 is cut from one end side. As shown in ()), a switching step is performed so that the ceramic green molded body 1 is cut from the other end side.
[0036]
If this switching step is performed, as shown in FIG. 1A, while the cutting step and the moving step are repeatedly performed, the remaining portion of the ceramic green molded body 1 to be cut from now on Since the relatively large number 11 exists, the displacement of the ceramic green compact 1 can be sufficiently prevented.
[0037]
On the other hand, as shown in FIG. 1 (2), while the cutting step and the moving step are repeatedly performed, the portion of the remaining portion 11 of the ceramic green compact 1 before cutting is shown in FIG. 1 (1). The position of the ceramic green compact 1 can be sufficiently prevented by the cut portion.
[0038]
Therefore, it is possible to make it difficult for the cutting blade 6 to shift the cutting position.
[0039]
The timing at which the above-described switching step is performed can be determined in advance, for example, as follows. That is, by performing the cutting process and the moving process on a trial basis, the time when the positional deviation exceeds the allowable range is grasped, and in the subsequent mass production system, the switching timing is determined based on the grasped time. What should I do?
[0040]
The number of the cutting lines 8 formed by cutting from one end of the ceramic green molded body 1 by repeating the cutting step and the moving step shown in FIG. According to experiments, it is preferable that the time be 20-80% of the total number of the cutting lines 8 to be formed in the ceramic green molded body 1, and more preferably that the time be about 50%. Has been confirmed. This experiment will be described below.
[0041]
With respect to the ceramic green compact 1 having a plane dimension of about 150 mm × about 150 mm, the amount of displacement when the arrangement pitch of the cutting lines 8 was 0.3 mm was measured. The result is shown in FIG. 3A and 3B are diagrams showing the influence of the number of cuts on the amount of positional deviation, wherein FIG. 3A shows a case where the cutting direction is not switched, and FIG. 3B shows a case where the cutting direction is switched. Is shown. Note that the positional shift amounts shown in FIG. 3 are measured as shown in FIG.
[0042]
FIG. 4A shows a method of measuring the amount of positional deviation before switching the cutting direction. As shown in FIG. 4 (a), when the cutting progresses from one end of the ceramic green molded body 1 in the direction indicated by the arrow 23, the amount of positional deviation on the other end side of the ceramic green molded body 1 is reduced. Measured on each of the left and right. The positional deviation amount shown in FIG. 3A and the positional deviation amount before switching the cutting progress direction shown in FIG. 3B are the positional deviation amounts measured by the method shown in FIG. .
[0043]
FIG. 4B shows a method of measuring the amount of displacement after switching the cutting direction. As shown in FIG. 4 (b), the positional deviation amount after switching the cutting progress direction is such that the cutting from one end of the ceramic green compact 1 is interrupted halfway, and then the other end of the ceramic green compact 1 Of the ceramic green compact 1 at the cutting line 8 formed at the end of the cutting from one end of the ceramic green molded body 1. Measured on each of the left and right. The position shift amount after the cutting direction switching shown in FIG. 3B is the position shift amount measured by the method shown in FIG. 4B.
[0044]
As shown in FIG. 3 (a), when the cutting direction is not switched, the displacement substantially occurs from the time when the number of cuts exceeds 20% of the total, and at the time when the number of cuts exceeds 80%, The amount of displacement is rapidly increasing. Finally, a displacement amount of 212 μm occurs.
[0045]
On the other hand, as shown in FIG. 3B, when the cutting progress direction is switched at the time when the number of cuts exceeds about 50% of the whole, even when the number of cuts reaches 80%, substantially No misalignment has occurred. Then, even after the cutting is completed, the amount of displacement can be suppressed to 24 μm.
[0046]
According to such experimental results, particularly the experimental results shown in FIG. 3A, the timing of switching between the cutting step and the moving step depends on the number of cuts formed by cutting from one end of the ceramic green compact 1. It can be seen that the number 8 is preferably set to a time when the number reaches 20 to 80% of the total number of cuts 8 to be formed in the ceramic green compact 1.
[0047]
The switching timing is not determined in advance as described above. Instead of repeating the cutting step and the moving step a plurality of times, the displacement of the ceramic green molded body 1 to be cut is sensed, and the sensed displacement is detected. It may be a point in time when the amount exceeds a predetermined threshold.
[0048]
For example, as shown in FIG. 1A, cameras 26 and 27 are arranged so that an image of the other end side of the ceramic green molded body 1 can be imaged. Then, the position information of the end face of the ceramic green molded body 1 captured by the cameras 26 and 27 is subjected to image processing to determine the amount of positional deviation. When the amount of positional deviation exceeds a predetermined threshold, the switching step is performed. Then, switching is performed to perform the cutting step and the moving step as shown in FIG. 2 (2).
[0049]
As described above, the cutting is performed over the entire area of the ceramic green molded body 1, and after the ceramic green molded body 1 is cut into a strip shape, the table 4 is turned 90 as shown by the arrow 28 in FIG. Rotated by degrees. In this rotation, the table 4 and the cutting blade 6 may be relatively rotated by 90 degrees. For example, the cutting blade 6 may be rotated by 90 degrees.
[0050]
Next, as shown in FIG. 1 (4), a cutting step similar to the cutting step and the moving step shown in FIG. And a moving step, a switching step is performed on the way, and then, as shown in FIG. 1 (5), the cutting step shown in FIG. 1 (2) from the other end side of the ceramic green compact 1 And the same cutting step and moving step as in the case of the moving step are performed.
[0051]
In FIGS. 1 (4) and 1 (5), elements corresponding to the elements shown in FIGS. 1 (1) and 1 (2) are denoted by the same reference numerals, and redundant description will be omitted.
[0052]
When the cutting shown in FIG. 1 (5) is completed as described above, the ceramic green compact 1 is divided into compacts having a plurality of chip shapes. After being fired, these chip-shaped compacts are used as component bodies for ceramic electronic components such as multilayer ceramic capacitors. For example, when a multilayer ceramic electronic component such as a multilayer ceramic capacitor is to be manufactured, the ceramic green molded body 1 is constituted by a multilayer body of a plurality of ceramic green sheets having an internal conductor film formed along a specific interface. Is done.
[0053]
Although the present invention has been described with reference to the illustrated embodiment, various other modifications are possible within the scope of the present invention.
[0054]
For example, in the illustrated embodiment, the cutting step and the moving step are switched only once, but the number of switching may be two or more. For example, the cutting from the one end of the ceramic green molded body 1 is performed by 20%, the cutting from the other end of the ceramic green molded body 1 is performed by 20%, and then the one end again. Switching may be performed multiple times, such as performing a cut from the side by 20% and then again performing a cut from the other end by 20%. Further, in an extreme case, although the time loss due to the moving step is large, the switching step is performed for each cutting, and the cutting from the other end side is the same as the cutting from the one end side of the ceramic green molded body. May be alternately repeated.
[0055]
【The invention's effect】
As described above, according to the present invention, the step of relatively moving the table and the cutting blade for suction-fixing the ceramic green molded body and the step of cutting the ceramic green molded body by the cutting blade are repeated a plurality of times. In cutting the ceramic green compact along a plurality of cutting lines arranged in the main surface direction, the ceramic green compact is cut from one end of the ceramic green compact, and the other end of the ceramic green compact is cut along the way. Since it is provided with a step of switching at least once so as to cut from the side, when cutting from one end side of the ceramic green molded body, the displacement of the ceramic green molded body due to the push-off of the cutting blade is still cut. The ceramic grease is advantageously stowed by the rest of the ceramic green compact When cutting from the other end side of the molded body, the misalignment of the ceramic green molded body is advantageously caused by a part of the ceramic green molded body that has not been cut yet and a portion that is cut from one end side of the ceramic green molded body. Can be stunted.
[0056]
Therefore, it is possible to reduce the displacement of the ceramic green compact due to the pushing of the cutting blade, and as a result, it is possible to reduce the displacement of the cutting position. Therefore, as in the case where the ceramic green compact is a laminate of a plurality of ceramic green sheets having an internal conductor film formed along a specific interface, the present invention is applied to cutting for obtaining a component body of a multilayer ceramic electronic component. Then, the displacement of the internal conductor film in each component body can be made less likely to occur, and the yield of the obtained multilayer ceramic electronic component can be improved.
[0057]
In the present invention, when the timing for performing the switching step is determined in advance, the ceramic green compact can be efficiently cut in a mass production system.
[0058]
In the above case, the switching is performed when the number of cuts formed by cutting from one end of the ceramic green molded body reaches 20 to 80% of the total number of cutting lines to be formed in the ceramic green molded body. If the process is performed, it is more effective to reduce the amount of displacement.
[0059]
Further, the timing of performing the switching step is a point in time when the positional deviation of the ceramic green compact to be cut is sensed while the cutting step is performed, and the amount of the detected positional deviation exceeds a predetermined threshold value. Then, even if the size and the like of the ceramic green molded body are changed, or even if the force of suction fixing by the table fluctuates, the switching step can always be performed at an appropriate time. Therefore, it is particularly advantageous when the cutting step is performed in a situation where a large variety of ceramic green compacts must be handled.
[0060]
Further, when the cutting step and the moving step as described above are completed, a strip-shaped molded body is obtained from the ceramic green molded body, and when the target molded body has a chip shape, the cutting step is performed. And after the moving step, the table and the cutting blade are relatively rotated by 90 degrees, and then the cutting step and the moving step are performed again. The cutting step and the moving step performed after the rotating step In this case as well, if the above-described switching step is performed, the displacement of the ceramic green compact can be reduced even in the latter cutting, and therefore, the displacement of the cutting position can be reduced.
[Brief description of the drawings]
FIG. 1 is a perspective view sequentially showing some typical steps included in a method for cutting a ceramic green compact according to an embodiment of the present invention.
FIG. 2 is a front view showing a state in which a ceramic green compact 1 is suction-fixed on a table 4, which is prepared in advance to carry out the cutting method shown in FIG.
FIGS. 3A and 3B show experimental results obtained by investigating the influence on the positional deviation amount due to repeated cutting, wherein FIG. 3A shows a case where the cutting direction is not switched, and FIG. This shows the case where the switching is performed.
4A and 4B are diagrams for explaining a method of measuring a positional deviation amount due to cutting, wherein FIG. 4A shows a method of measuring a positional deviation amount before switching the cutting direction, and FIG. 4B shows a positional deviation amount after switching the cutting direction. The measurement method of is shown.
FIG. 5 is a perspective view showing a state in which a conventional method for cutting a ceramic green compact, which is of interest to the present invention, is being performed.
6 is a front view showing a ceramic green compact 1 and a cutting blade 6 for explaining a problem that may occur by the cutting method shown in FIG.
FIG. 7 is a front view showing a deformed state of the ceramic green compact 1 for explaining a problem when the guide 13 is used.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ceramic green molded body 2, 3 Main surface 4 Table 6 Cutting blade 8 Cutting line 11 Remaining part 12 Misalignment 26, 27 Camera

Claims (6)

A step of suction-fixing a ceramic green molded body having opposing main surfaces on a table,
By lowering the cutting blade toward the main surface of the ceramic green molded body, a step of cutting the ceramic green molded body by pressing and cutting,
The step of relatively moving the table and the cutting blade,
By repeating the cutting step and the moving step a plurality of times, the ceramic green molded body is cut along a plurality of cutting lines arranged in a main surface direction of the ceramic green molded body. A cutting method,
By repeating the cutting step and the moving step a plurality of times, cutting from one end side of the ceramic green molded body, and in the middle thereof, cutting from the other end side of the ceramic green molded body, at least. A method for cutting a ceramic green compact, further comprising a step of switching once. The method for cutting a ceramic green compact according to claim 1, wherein a timing at which the switching step is performed is determined in advance. The timing of performing the switching step is such that the number of the cutting lines formed by cutting from one end side of the ceramic green molded body by repeating the cutting step and the moving step a plurality of times, The method for cutting a ceramic green molded body according to claim 2, wherein the time is set to a point in time when 20 to 80% of the total number of the cutting lines to be formed in the green molded body is reached. The timing of performing the switching step is to sense the displacement of the ceramic green molded body to be cut while repeating the cutting step and the moving step a plurality of times, and the sensed displacement amount is a predetermined amount. The method for cutting a ceramic green compact according to claim 1, wherein the cutting is performed when the threshold value is exceeded. The method for cutting a ceramic green molded body according to any one of claims 1 to 4, wherein the ceramic green molded body is a laminate of a plurality of ceramic green sheets having an internal conductor film formed along a specific interface. After the cutting step and the moving step are completed, the method further includes a step of rotating the table and the cutting blade relatively 90 degrees, and then, the cutting step and the moving step including the switching step 6. The method for cutting a ceramic green molded body according to claim 1, wherein the method is repeated.

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