JP2504276B2 - Method and apparatus for laminating ceramic green sheets - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for stacking ceramic green sheets encountered in a manufacturing process of a multilayer ceramic electronic component such as a multilayer ceramic capacitor. In particular, the present invention relates to an improvement for enabling highly accurate stacking.

[Prior Art] Conventionally, the following methods and devices have been applied to stack ceramic green sheets.

First, a mother sheet, from which a ceramic green sheet to be laminated is taken out, is formed on a carrier film made of polyester, for example. At this stage, if necessary, a conductive film such as internal electrodes is formed on the surface of the mother sheet by screen printing or the like.

Next, as shown on the left side of FIG. 2, the mother sheet 1
Is conveyed to the punching table 3 while being held on the carrier film 2. The punching table 3 is provided with a plurality of suction holes 4. Negative pressure is applied to the suction holes 4, whereby the mother sheet 1 is positioned with respect to the punching table 3 via the carrier film 2.

Above the punching table 3, as indicated by arrow 5,
A pick-up device 6 that can approach and separate from the table 3 is arranged. The pickup device 6 includes a head 9 that provides a contact surface 8 that contacts one main surface of the ceramic green sheet 7 that is about to be stacked, and the contact surface 8.
A cutting blade 10 arranged around the head 9 so as to surround and project from the contact surface 8. The head 9 has a plurality of air holes 11 that open to the contact surface 8. Further, the cutting blade 10 is fixedly attached to a slider 12 which is vertically slidable on a peripheral surface of the head 9 within a predetermined range. A compression spring 13 constantly applies a downward force to the slider 12.

Such a pickup device 6 is used for the punching table 3
Applies to Mother Sheet 1 above. As a result, the cutting blade 10 forms a closed loop cutting line 14 in a predetermined area of the mother sheet 1. At this time, the cutting blade 10 is a compression spring.
As the slider 12 slides against the elasticity of 13, the upper side of the head 9 is adjusted so that the degree of protrusion from the contact surface 8 is small enough to form the cutting line 14 on the mother sheet 1. Move relative to.

Next, the pickup device 6 is retracted from the mother sheet 1. As a result, the ceramic green sheet 7 provided by the area surrounded by the cutting line 14 is cut out from the mother sheet 1 as the pickup device 6 retracts, as shown on the left side of FIG. At this time, a negative pressure is applied to the air hole 11 provided in the head 9, and the ceramic green sheet 7 to be stacked is adsorbed to the contact surface 8.

Next, as shown by the arrow 15, the pickup device 6
It is moved above the stacking table 16.

The stacking table 16 has a heater 17 built-in, and can be moved in the vertical direction by an up-and-down drive device 18 that also functions as a pressurizing device, as shown by an arrow 19. Further, the stacking table 20 is arranged on the stacking table 16.

As described above, the pickup device 6 is used for the stacking table 16
When it is moved upward, the stacking table 16 is moved upward. As a result, the ceramic green sheet 7 already placed on the stacking table 20 and the ceramic green sheet 7 that has been conveyed by the pickup device 6.
While being heated by the heater 17, they are pressed against each other. Note that the laminated state of the ceramic green sheets 7 may be fixed by adhesion with a solvent without applying such heat and pressure.

Next, the stacking table 16 is lowered, and the ceramic green sheet 7 held on the pickup device 6 side.
Are held on the stacking table 16 side. At this time, a positive pressure may be applied to the air hole 11 in order to facilitate the separation of the ceramic green sheet 7 and the contact surface 8 of the pickup device 6.

After that, the same steps are repeated a desired number of times, and the ceramic green sheets 7 are stacked on the stacking table 20 a desired number of times.

[Problems to be Solved by the Invention] However, the conventional methods and apparatuses described above have the following problems to be solved.

That is, the ceramic green sheets 7 to be stacked are punched from the mother sheet 1 on the punching table 3, then transported by the pickup device 6 and stacked on the stacking table 16 located at another place. Therefore, such movement of the ceramic green sheets 7 inevitably involves an error, so that the stacking accuracy of the ceramic green sheets 7 on the stacking table 16 is inevitably lowered.

Further, as mentioned above, when the adhesion by the solvent is used in stacking the ceramic green sheets 7, static electricity generated when the ceramic green sheets 7 are peeled from the carrier film 2 causes a failure in stacking the ceramic green sheets 7. May occur.

Further, since a mechanism for moving the pickup device 6 as shown by the arrow 15 is required, the structure of the device becomes complicated.

Therefore, an object of the present invention is to provide a method and apparatus for laminating ceramic green sheets, which can solve the above-mentioned problems.

[Means for Solving the Problems] The ceramic green sheet laminating method according to the present invention is characterized by including the following steps in order to solve the above-mentioned technical problems.

That is, a mother sheet from which the ceramic green sheets to be laminated are taken out is prepared.

On the other hand, a pickup device is provided which comprises a contact surface for contacting one main surface of the first ceramic green sheet to be laminated, and a cutting blade arranged to surround the contact surface and project from the contact surface. .

Further, a heater for thermocompressing the laminated ceramic green sheets is prepared.

Then, the pickup device is moved to the mother sheet to apply the pickup device to the mother sheet, and a cutting line forms a closed loop in a predetermined region of the mother sheet by the cutting blade.

The ceramic green sheet laminated on the contact surface and the ceramic green sheet provided by the area surrounded by the cutting line are thermocompression bonded by heat from the heater and pressure applied by the contact surface.

Then, the pickup device is retracted from the mother sheet, whereby the ceramic green sheet provided by the area surrounded by the cutting line that is heat-pressed to the ceramic green sheet laminated on the contact surface is provided as the pickup sheet retracts the mother sheet. Cut out from.

Then, the step of forming such a cutting line, the step of thermocompression-bonding, and the step of cutting out the ceramic green sheet are repeated, whereby a plurality of ceramic green sheets are thermocompressed by a heater, thereby cutting blades. Are laminated on the contact surface surrounded by.

The present invention also provides a laminating apparatus suitable for carrying out the laminating method as described above.

A laminating apparatus according to the present invention includes a table on which a mother sheet for taking out ceramic green sheets to be laminated is placed, and a pickup device provided above the table so as to be close to and separable from the table. And a heater for thermocompressing the laminated ceramic green sheets. The pickup device includes a head that provides a contact surface that contacts one main surface of the first ceramic green sheet to be laminated, and a cutting blade that surrounds the contact surface and that is disposed around the head so as to protrude from the contact surface. Prepare Further, the degree of protrusion of this cutting blade from the contact surface is within the range of the degree of protrusion, and all of the desired number of laminated ceramic green sheets are laminated on the contact surface by thermocompression bonding with a heater. It is chosen to be possible.

[Operation] According to the present invention, the ceramic green sheets to be laminated, which are punched from the mother sheet with the cutting blades, are surrounded by the cutting blades by thermocompression bonding of the ceramic green sheets even after cutting. In the space, all of the desired number of the ceramic green sheets are laminated by thermocompression bonding.

[Effects of the Invention] As described above, according to the present invention, since the ceramic green sheets are laminated inside the cutting blade punched with the ceramic green sheets to be laminated, the accuracy at the time of punching the ceramic green sheets is improved. Is directly reflected in the lamination of the ceramic green sheets. Therefore, the ceramic green sheets can be stacked with high accuracy.

Further, according to the present invention, a mechanism for moving the pickup device between the upper side of the punching table and the upper side of the stacking table, which is required in the prior art, is not required, so that the structure of the laminating apparatus can be simplified.

Further, according to the present invention, it is not necessary to punch the ceramic green sheets and then convey them to the stacking table, so that the ceramic green sheets can be stacked efficiently.

[Embodiment] FIG. 1 is a sectional view showing a ceramic green sheet laminating apparatus according to an embodiment of the present invention.

A mother sheet 21 from which a ceramic green sheet to be laminated is taken out is prepared in a state of being formed on a carrier film 22 made of polyester, for example. Although not shown, a conductive film such as an internal electrode is formed on the surface of the mother sheet 21 by screen printing or the like, if necessary.

The mother sheet 21 is carried by the carrier film 22 to the table 23. A heater 24 is built in the table 23. Further, the table 23 is provided with a plurality of suction holes 25. Therefore, when a negative pressure is applied to the suction holes 25, a suction force is exerted on the carrier film 22, whereby the mother sheet 21 is positioned with respect to the table 23.

Above the table 23, there is an arrow 26 against the table 23.
As shown by, the pickup device 27 is arranged so as to be close to and away from each other, that is, movable in the vertical direction.

The pickup device 27 includes a head 30 that provides a contact surface 29 that contacts one main surface of the first ceramic green sheet 28 (a) to be laminated, and a head that surrounds the contact surface 29 and projects from the contact surface 29. A cutting blade 31 arranged around 30 is provided.

More specifically, the head 30 has a plurality of air holes 32.
It is provided so as to open at the contact surface 29. On the other hand, the cutting blade 31 is attached to a slider 33 which is slidable on the outer periphery of the head 30 in the vertical direction by a predetermined distance. The slider 33 is biased by the compression spring 34 so as to always be displaced downward. The degree of protrusion of the cutting blade 31 from the contact surface 29 is, for the reason described below, of the conventional cutting blade 10 described above,
It is selected to be larger than the degree of protrusion from the contact surface 8.

Using such a pickup device 27, the ceramic green sheets 28 are punched and laminated.

More specifically, first, the pickup device 27 is applied to the mother sheet 21, so that the cutting blade 31 forms a cutting line 35 forming a closed loop in a predetermined region of the mother sheet 21. When the pickup device 27 is applied to the mother sheet 21 as described above, the pickup device 27 is
It must be accurately aligned with the mother sheet 21 or the conductive film formed on the surface thereof. Therefore, although not shown, at least one of the mechanism for transporting the pickup device 27 and the mother sheet 21 onto the table 23 is preferably provided with a mechanism for performing such alignment. Also, as mentioned above,
When the cutting line 35 is formed on the mother sheet 21 by the cutting blade 31, the cutting blade 31 is a slider against the elasticity of the compression spring 34.
While performing the sliding operation of 33, head until the protruding state is sufficient to form the cutting line 35 on the mother sheet 21.
Displace upward relative to 30.

The table 23 is heated to about 90 ° C. by the heater 24, for example.

Then, the pickup device 27 is retracted from the mother sheet 21. As a result, the ceramic green sheet 28 provided by the area surrounded by the cutting line 35 is cut out from the mother sheet 21 as the pickup device 27 retracts. At this time, a negative pressure is applied to the air holes 32 provided in the head 30, and the first ceramic green sheet 28 (a) to be laminated is adsorbed on the contact surface 29 and also the carrier film. Stripped from 22.

Then, the same steps are repeated, and all of the desired number of laminated ceramic green sheets 28 are laminated in the space surrounded by the cutting blade 31.

When the second and subsequent ceramic green sheets 28 are punched from the mother sheet 21, more accurately, the cutting line 35 is formed on the mother sheet 21 to punch the second and subsequent ceramic green sheets 28. apparatus
When the 27 is brought close to the table 23, the pickup device 27
A pressure of, for example, about 20 kg / cm ² is applied between the table and the table 23. As a result, the laminated ceramic green sheets 28 are thermocompression bonded to each other. The table 23 heated as described above heats the ceramic green sheet 28. This heating acts to melt the binder contained in the ceramic green sheet 28 and increase its viscosity. Such melting of the binder enhances the degree of bonding between the laminated ceramic green sheets 28.

In this way, after the ceramic green sheets 28 are stacked on the contact surface 29 of the pickup device 27 by a desired number, the stacked body of the ceramic green sheets 28 is taken out from the pickup device 27. At this time, preferably, a positive pressure is applied to the air holes 32 to facilitate such extraction.

Although the present invention has been described above with reference to the preferred embodiments shown in the drawings, various other modifications are possible within the scope of the present invention.

For example, the cutting blade 31 is moved by the compression spring 34 to the head 30.
However, it is not always necessary to hold the cutting blade 31 with such a spring. For example, it is possible to use a pickup device having a structure in which the degree of protrusion of the cutting blade 31 from the contact surface 29 can be gradually increased as the stacking of the ceramic green sheets 28 progresses. Further, the configuration in which the cutting blade 31 is displaced with respect to the head 30 is not always necessary, and the cutting blade 31
31 may be fixedly provided to the head 30.

Further, the air hole 32 provided in the head 30 is not always necessary. Even if there is no negative pressure applied from the air holes 32, the ceramic green sheet 28 can be formed on the contact surface 29.
Is sometimes held properly.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a ceramic green sheet laminating apparatus according to an embodiment of the present invention. FIG. 2 is a schematic sectional view for explaining a conventional method and apparatus for laminating ceramic green sheets. In the figure, 21 is a mother sheet, 23 is a table, 27 is a pickup device, 28 is a ceramic green sheet, 29 is a contact surface, 30 is a head, 31 is a cutting blade, and 35 is a cutting line.

Claims (2)

(57) [Claims] 1. A mother sheet is provided from which a ceramic green sheet to be laminated is prepared, a contact surface for contacting one main surface of the first ceramic green sheet to be laminated, and a surface surrounding and surrounding said contact surface. A pickup device having a cutting blade arranged to project from the contact surface is prepared, a heater for thermocompressing the laminated ceramic green sheets is prepared, and the pickup device is moved with respect to the mother sheet. By applying the pickup device to the mother sheet, thereby forming a cutting line forming a closed loop in a predetermined region of the mother sheet by the cutting blade, a ceramic green sheet laminated on the contact surface,
The ceramic green sheet provided by the area surrounded by the cutting line is thermocompression bonded by heat from the heater and pressure applied by the contact surface, and the pickup device is retracted from the mother sheet, thereby, Forming the cutting line by cutting out the ceramic green sheet provided by the area surrounded by the cutting line thermocompression bonded to the ceramic green sheet laminated on the contact surface from the mother sheet as the pickup device retracts. The step of thermocompression bonding and the step of cutting out the ceramic green sheet are repeated, whereby a plurality of ceramic green sheets are each heated by the electric heat of the heater to be thermocompression bonded, thereby being surrounded by the cutting blade. Stacked on the contact surface, each Provided with a step, ceramic green sheet method of stacking. 2. A table on which a mother sheet for taking out the ceramic green sheets to be laminated is placed, and a pickup device provided above the table so as to be able to approach and separate from the table. A heater for thermocompressing the laminated ceramic green sheets to each other, and the pickup device includes a head that provides a contact surface that contacts one main surface of the first ceramic green sheet to be laminated, and a contact surface. A cutting blade surrounding and surrounding the head is provided so as to project from the contact surface, and the degree of projection of the cutting blade from the contact surface is within the range of the projection degree. All of the desired number of laminated ceramic green sheets are heated and thermo-compressed by electric heating of the heater. It is chosen such that it can be laminated by bringing the laminated device of the ceramic green sheet.