JPH0818315B2 - Magnetic green sheet laminating apparatus and laminating method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic green sheet laminating apparatus for laminating magnetic green sheets containing magnetic ceramics and a laminating method therefor. A conductor forming an inductor is provided inside a chip-shaped magnetic ceramic body. The present invention relates to a green sheet laminating method and device applicable to the manufacture of embedded multilayer chip inductors.

[0002]

2. Description of the Related Art A method for producing a laminated chip inductor by laminating magnetic green sheets containing magnetic ceramics and embedding conductors inside the green sheets is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei.
It is known from Japanese Patent No. 151403. A general method for manufacturing this type of laminated chip inductor is, for example, the following series of steps.

First, a green sheet made of magnetic powder such as ferrite and an organic binder is formed.
Next, through holes are formed at predetermined positions on the green sheet. Further, a conductive paste is used on one surface of the green sheet to print a coil pattern having an arc shape or a U-shape. At this time, the position where the coil pattern is printed is selected at a position where one end of the coil pattern and the through hole overlap each other and both are short-circuited. Then, the green sheets are laminated so that the coil patterns are connected between the layers through the through holes, and the green sheets are thermocompression bonded to be integrated. Here, the laminate obtained as a result of the above steps is cut into chips, separated, and fired. Then, an external electrode is formed on each of the obtained chips to complete the multilayer chip inductor.

On the other hand, an apparatus and method for cutting a green sheet into a predetermined shape and laminating the green sheet are disclosed in, for example, Japanese Patent Publication No. 2-158.
It is known from publication 306. The step of laminating the green sheets will be described in detail. First, the green sheet obtained by mixing the organic binder and the like is placed on a conveyor device and conveyed. Next, this green sheet is cut into a predetermined shape at a predetermined position, and at the same time, it is adsorbed on the lower surface of the stacking head by the action of the vacuum adsorption mechanism,
The cut green sheets are transferred to a stacking plate for stacking them in a predetermined order and held on the surface thereof.

Subsequently, the green sheet held by the laminating head is lowered onto the laminating plate and temporarily press-bonded (5 to 15 tons) from its upper surface. The pressing is performed here so that the stacked green sheets do not shift when the laminated plates described later are moved. After repeating the above operation and stacking a predetermined number of green sheets, the obtained green sheet stack is conveyed to a pressing machine and temporarily pressure-bonded (20 to 30 tons), and thereafter,
The obtained laminated body is peeled from the laminated plate and pressure-bonded under high pressure by another press machine to be integrated.

[0007]

By the way, in the above-mentioned prior art, in the process of cutting the green sheets into a predetermined shape and then transferring and stacking the plurality of green sheets on the stacking plate, the green sheets are stacked. Since it is crimped (temporarily crimped) every time it is placed on the plate,
The green sheet on the lower layer side is repeatedly pressed and crushed. As a result, the accuracy and reliability of the completed multilayer chip inductor deteriorate, and the accuracy of the inductance value of the inductor formed inside the chip is also adversely affected. Further, there is a problem that the productivity of the laminated chip inductor is reduced due to the time required for the temporary pressure bonding step performed each time the green sheet is placed on the laminated plate. Further, in order to improve productivity, when the green sheet is placed on the laminated plate without performing the above-mentioned temporary pressure bonding, a lateral shift occurs between the laminated green sheets, and the obtained laminated chip is obtained. There was a problem that the characteristics of the inductor deteriorated and the inductance also deviated from the expected value.

Further, since the temporary pressing is performed every time the green sheet is placed on the laminated plate, a pressurizing machine is required, the manufacturing apparatus becomes large, and the operating cost thereof increases. It was The purpose of the present invention is to
A magnetic green sheet laminating apparatus capable of solving the above-mentioned problems in the prior art and accurately laminating a magnetic green sheet of a predetermined shape on a laminated plate with a relatively simple configuration without causing lateral displacement. To provide
Another object of the present invention is to provide a method of manufacturing a laminated chip inductor that can manufacture a laminated chip inductor having stable electric characteristics at a relatively low cost.

[0009]

In order to achieve the above-mentioned object, in the present invention, firstly, a stage movable on a plane, an elevating mechanism attached to the stage, and a laminating head attached to the elevating mechanism. And a laminated plate,
In a magnetic material green sheet laminating apparatus that performs an operation of laminating a plurality of green sheets containing magnetic ceramics of a predetermined shape on the surface of the laminating plate from the laminating head, the laminating plate has a magnetism generating means. Provided is a magnetic green sheet laminating apparatus. Secondly, in a method of laminating a plurality of green sheets containing magnetic ceramics as a main component, the green sheets conveyed to a predetermined position are held by a laminating head, and on a laminated plate provided with a magnetic generation means. A multilayer chip inductor manufacturing method characterized by stacking a plurality of layers of green sheets by repeating placing on a sheet.

[0010]

According to the present invention, when a magnetic green sheet containing magnetic ceramics is placed on a laminated plate by a laminating head, it is generated by a magnetism generating means arranged on the surface of the laminated plate. By attracting and holding by using the magnetic force, it is possible to reliably hold the magnetic green sheets having a predetermined shape even if a plurality of magnetic green sheets are stacked without lateral displacement without performing temporary pressure bonding. Moreover, since it can be held at a fixed position by magnetic force without performing temporary pressure bonding, instability and non-uniformity of the laminated state due to crushing due to temporary pressure bonding, lateral displacement, etc., in particular, in the lower layer of the laminated body are eliminated. This makes it possible to manufacture a multilayer chip inductor having high productivity, low cost, and stable performance with a relatively simple device.

[0012]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. First, in FIG.
A schematic configuration of a manufacturing apparatus for a laminated chip inductor is shown, and reference numeral 1 in the drawing indicates a conveyor device, and a magnetic material green sheet 100 is provided on the conveyor belt 11.
Is continuously supplied.

The magnetic green sheet 100 is made of Fe.
Ni-Z containing ₂ O ₃ , ZnO, NiO and CuO as main components
Polyvinyl butyral is used as a binder in n-Cu ferrite powder to form a long ferrite green sheet having a thickness of 100 μm by the doctor blade method. As shown in FIG. 2, this green sheet 100 is cut into a predetermined size to form a rectangular green sheet, and a through hole 101 is further provided at a predetermined position of this green sheet. The coil pattern 102 is formed on the surface using a conductor paste. Furthermore, magnetic green sheet 1
In addition to the above-mentioned green sheets, a magnetic green sheet and a cover green sheet 10 in which the above through holes are not formed and the coil pattern is not printed are denoted as 00.
0C is also available. These cover green sheets 100C are to be laminated on both end faces of the above-described magnetic green sheets 100, which will be described later, as will be apparent. Further, reference numeral 24 in the drawing, which will be described later in detail, is a laminated plate on which the green sheet is placed.

The magnetic green sheet 100 manufactured as described above is placed on the conveying path of the conveyor device 1 shown in FIG. 3, and the magnetic green sheet laminating device of the present invention is used for the laminating section 2. Be transported to. This laminated part 2
As shown in FIG. 3, a base 20 arranged below the conveyor belt 11 of the conveyor device 1, a laminating head 21 arranged above the base 20, and a lifting mechanism for vertically moving the laminating head. 22 and a moving stage device 23 to which the elevating mechanism is attached in order to move the stacking head in the X and Y directions. Further, reference numeral 12 in the drawing indicates a belt rail.

On the other hand, as shown in FIG. 5, a urethane rubber frame 201 is attached to the outer periphery of the base 20 of the laminated portion 2 so as to surround it. Further, the laminating head 21 has a cutter blade 211 on the side of the lower end thereof.
Is attached to a position corresponding to the urethane rubber frame 201 of the base 20, and the lower surface thereof serves as a holding portion 212 for the magnetic green sheet. That is, as shown in FIG. 6, the electromagnets 213 and 213 are formed on the plane as the holding portion 212 on the lower surface of the laminated head 21.
A plurality of ... Are arranged. This electromagnet 213 is shown in FIG.
As shown in FIG. 5, it is composed of an electromagnetic coil 2132 that is wound around the core 2131 and a magnetic path member 2133 that is annularly drawn from the core 2131.

As shown in FIG. 4, a laminating plate 24 is arranged adjacent to the laminating head 21. As shown in FIG. 1, the laminated plate 24 has a plurality of magnets 241, 241 ... Arranged in stripes on the surface so that N poles and S poles alternate. Further, in FIG. 3, a pressing device 3 for pressing and press-bonding the laminated magnetic material green sheets on the conveyance destination side of the laminated portion 2 is further provided on the conveyance destination side. A cutting device 4 for cutting and dividing the green sheet into chips and a firing furnace 5 for firing the cut and divided chip-shaped magnetic material laminated green sheets are provided.

The operation of the above-described multilayer chip inductor manufacturing apparatus will be described in detail below with reference to the drawings. First, in FIG. 5A, the magnetic green sheet 100 for a laminated chip inductor obtained as described above is the conveyor belt 1 of the conveyor device 1.
It is transported onto the base 1 and placed on the base 20 of the stacking unit 2. At this time, the belt rails 12, 12 supporting the conveyor belt 11 are lowered, and the magnetic green sheet 10 is
0 is fixed on the base 20. Therefore, as shown in FIG. 5B, the stacking head 21 arranged above the base is lowered to move the magnetic green sheet 100 into a predetermined shape and size (for example, 15 × in this embodiment). The magnetic green sheet 100, which is cut into a 15 cm square) and cut into a predetermined shape, is adsorbed and held by the holding portion 212 on the lower surface of the stacking head 21. That is, at this time, the plurality of electromagnets 213, 213 ... (See FIG. 7) arranged on the plane of the holding portion 212 of the stacking head are energized to generate lines of magnetic force. This line of magnetic force passes through the magnetic material green sheet 100 as shown by the broken line arrow in FIG.
Hold it in close contact with the flat surface of 2. At this time, the magnetic green sheet initially supplied by the conveyor belt 11 is the cover green sheet 100C.

After that, the laminated head 11 holds the magnetic green sheet cut into a predetermined shape in its holding portion 21.
It rises and returns to the original position while it is adsorbed and held on 2.
At the same time, the above-mentioned belt rails 12 and 12 are also raised, and the remaining magnetic green sheet 100 having a predetermined shape cut.
Is lifted from the base 20 and moved to the side to be removed.

Then, the next magnetic green sheet 100 is formed.
Are transferred and fed onto the conveyor belt 11, fixed on the base 20 and cut into a predetermined shape in the same manner as described above. At the same time, the magnetic green sheet 100 cut into the predetermined shape is used in the stacking head 21 by the previous operation.
It is further laminated on the magnetic green sheet 100 which is adsorbed and held by the holding part 212. That is, by repeating the above operation a predetermined number of times, the stacking head 2
A predetermined number of magnetic green sheets 100 are automatically stacked on one holding portion 212 at an accurate position.

The laminated magnetic green sheets 100 laminated in a predetermined number as described above are then laminated.
In step (1), it is placed on the laminating plate 22 arranged adjacent to the laminating head 21 (see FIG. 4). That is, after the stacking head 21 is raised by the elevating mechanism 22, it is moved to the position of the stacking plate 24 by the moving stage device 23 in the X and Y directions, and is lowered and placed on the surface of the stacking plate 24. At the same time, stacking head 2
1 reduces or interrupts the current supplied to the electromagnets 213, 213 ... Of the holding portion 212. On the other hand, since a plurality of magnets 241, 241 ... Are provided on the surface of the laminated plate 24, the laminated green sheet 100 made of a magnetic material does not need to be temporarily pressure-bonded as in the conventional case.
It is reliably placed on the laminated plate 24 without lateral displacement.

After that, the laminated green sheet 100 placed on the laminated plate 24 is thermocompression-bonded by the pressing device 3 at a temperature of 100 ° C. and a pressure of 300 kg / cm ² for integration, and then a cutting device. After being cut and divided into chips by 4, the baking furnace 5 for example 900 ° C
It is baked at the temperature of. Further, a conductive paste containing Ag or the like as a main component was applied to both end faces of this chip-shaped fired body, and this was baked at a temperature of, for example, 800 ° C. to form external electrodes, thereby completing a multilayer chip inductor.

In the above embodiment, an electromagnet is used as the magnetic generator provided on the plane of the holding portion 212 of the laminating head 21, but the present invention is not limited to this, and for example, a permanent magnet is used and then the adsorbed laminated layer is used. It is also possible to send compressed air or the like into the gap when removing the green sheet. The magnet on the laminated plate 24 can also be an electromagnet. Further, the stacking head 21 is
As described above, not only the type in which a plurality of sheets are stacked and held on the holding surface 212, but also the type in which green sheets are stacked one by one on the stacking plate 24 can be similarly adopted. It is possible to stack a plurality of layers reliably and laterally without the need for temporary pressure bonding.

[0023]

As is apparent from the above description, according to the magnetic material green sheet laminating apparatus and method of the present invention, the magnetic force is utilized instead of the conventional temporary pressure bonding.
With a relatively simple structure, it is possible to uniformly and surely stack the magnetic green sheets cut into a predetermined shape on the stacking plate without causing crushing or lateral deviation in some of the layers.

[Brief description of drawings]

FIG. 1 is a partially enlarged top view showing a structure of a laminated surface of a laminated plate of a magnetic green sheet laminating apparatus of a laminated chip inductor manufacturing apparatus, which is a characteristic of the present invention.

FIG. 2 is a developed perspective view showing details of a magnetic green sheet laminated by the laminated chip inductor manufacturing apparatus.

FIG. 3 is a schematic configuration diagram illustrating an outline of a multilayer chip inductor manufacturing apparatus that employs the above magnetic green sheet stacking apparatus.

FIG. 4 is a side view showing an overall structure of a laminated portion of a laminated chip inductor manufacturing apparatus adopting the above magnetic green sheet laminating apparatus.

FIG. 5 is a cross-sectional view of a main part of a stacking head for explaining the operation of the magnetic green sheet stacking device.

FIG. 6 is a bottom view showing the bottom structure of the laminated head.

FIG. 7 is a partially enlarged cross-sectional view showing the detailed structure of an electromagnet provided on the bottom surface of the stacking head, for explaining the magnetic green sheet holding structure of the stacking head.

[Explanation of symbols]

 1 Conveyor Device 11 Belt Conveyor 2 Laminating Unit 20 Base 21 Laminating Head 211 Cutter Blade 212 Holding Unit 213 Electromagnet 22 Elevating Device 23 Moving Stage Device 24 Laminating Plate 241 Magnet 3 Pressing Device 4 Cutting Device 5 Baking Furnace 100 Magnetic Green Sheet 101 Through hole 102 coil pattern

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Masami Shimakata, 6-16-20 Ueno, Taito-ku, Tokyo Within Taiyo Denki Co., Ltd. (72) Kenichi Hoshi, 6-16-20 Ueno, Taito-ku, Tokyo Within Taiyo Electric Co., Ltd.

Claims (3)

[Claims] 1. A stage, which is movable on a plane, an elevating mechanism attached to the stage, a laminating head attached to the elevating mechanism, and a laminating plate, and contains magnetic ceramics of a predetermined shape. A magnetic material green sheet laminating apparatus for performing an operation of laminating a plurality of green sheets on the surface of the laminating plate from the laminating head, wherein the laminating plate has a magnetism generating means. 2. The laminating apparatus according to claim 1, wherein magnets having different polarities are arranged at a constant distance on the surface of the laminating plate. 3. A method for stacking a plurality of green sheets containing magnetic ceramics as a main component, wherein the green sheets conveyed to a predetermined position are held by a stacking head, and a stacking plate provided with a magnetism generating means. A method for manufacturing a laminated chip inductor, characterized in that a plurality of green sheets are laminated by repeating placing on the top.