JPH0423810B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a sheet lamination method for laminating green sheets and other sheets for laminated ceramic capacitors, for example.

Conventional Structures and Their Problems In general, multilayer ceramic capacitors are constructed by printing electrodes on ceramic green sheets and stacking several dozen sheets on top of one another. In the green sheet lamination method in which a multilayer capacitor is formed by stacking several dozen green sheets printed on electrodes in this manner, air contained between the green sheets must be effectively removed.

However, in the conventional lamination method, the green sheets are carefully pressed by hand or with a jig to remove air, which has the drawback of poor lamination efficiency and very low yield.

OBJECT OF THE INVENTION An object of the present invention is to provide a sheet stacking method that can improve workability during sheet stacking and also improve yield.

Structure of the Invention The sheet stacking method of the present invention is characterized in that when sheets are sequentially stacked, air contained between the stacked sheets is mechanically removed.

DESCRIPTION OF THE EMBODIMENT FIGS. 1 and 2 show an embodiment of the present invention, in which 1 is a punch for heating and pressurizing a green sheet, 2 is a die for cutting the green sheet, and 3 is a die for cutting the green sheet. A knock-out plate that removes the air contained between the green sheets and takes out the stacked green sheets when the stacking is completed, 4 is a connection pipe to the vacuum suction device, 6 is a rod heater for heating the punch 1, 7 is the punch This is a temperature measuring body for detecting the temperature of 1.

In such a configuration, frame 1 is
The green sheet 5 pasted on the green sheet 3 is set on the frame 14, and is conveyed to a predetermined position by a slider 19 that moves on a slide shaft 20 by a driving means. When the frame 13 is set in a predetermined position, the pressurizing hydraulic cylinder 12 moves forward and the punch holder 9 begins to descend. The punch 1 is attached to the punch holder 9 via a heat insulating plate 8, and an adjuster bolt 18 is attached via a bracket 17.
begins to descend. When the punch holder 9 descends to a certain extent, the adjuster bolt 18 presses the frame 14, the frame 14 also descends, and the guide hole 13a provided in the frame 13 is aligned with the guide pin 2a provided in the die 2. . The instant after the green sheet 5 is aligned in this manner, the punch 1 and the die 2 cut the green sheet 5 at its outer periphery. The green sheet 5 cut at the outer periphery is pressed onto the knockout plate 3 while being pressed by the punch 1.

The punch 1 is heated to a predetermined temperature by a rod heater 6 monitored by a temperature sensor 7, and the green sheet 5 is pressurized and heated. In this state, when vacuum suction is applied from the outer circumferential hole 3a of the knockout plate 3 through the pipe 4, as shown in FIG.
The air contained between the green sheets 5 is pushed out to the outer periphery by being heated and pressurized, and the air is vacuum-suctioned from the outer periphery hole 3a of the knockout plate 3. For this reason, knockout plate 3
is formed into a substantially arcuate curved surface so that the center part has a strong contact and the outer periphery has a weak contact so that air can spread in the outer circumferential direction. The purpose of pressurizing and heating the green sheet 5 is not only to remove air, but also to bond the green sheet 5 and the knockout plate 3 and the green sheets 5 together. After pressurizing and heating for a predetermined period of time, the pressurizing hydraulic cylinder 12 begins to retreat, and as the punch holder 9 rises, the frame 13 set in the frame frame 14
The frame frame 14 is lifted by the spring pressure of the compression coil spring 15, so that the frame 14 is raised. When the frame frame 14 has finished rising, the frame 13 is returned to its original position by the slide shaft 20, slider 19 and driving means, completing one cycle. By repeating the above cycle, the green sheets 5 are sequentially stacked. The last stacked green sheet 5 is taken out by a knockout plate 3 driven by a hydraulic cylinder 21.

Figures 3 to 7 show each step in the above cycle, with Figure 3 showing the setting of the frame 13 in its regular position, Figure 4 showing the lowering of the punch holder 9 and frame 14, and Figure 5 Cutting the outer periphery of green sheets, stacking green sheets and removing air, 6th
The figure shows each step of lifting the punch holder 9 and the frame.

In addition, in this example, the air was removed at the same time as the Daleen sheets were laminated one by one, but in addition to this, several dozen green sheets were laminated and then heated, pressurized, and vacuum treated all at once. It goes without saying that the air contained between the green sheets may be removed.

Effects of the Invention As described above, according to the present invention, the drawbacks of the green sheet lamination method, such as the presence of air between sheets, are eliminated, and the yield and quantity change in the production of laminates can be improved. It also has the advantage that air can be removed within the lamination process (in the same equipment) or outside the lamination process (in separate equipment).

[Brief explanation of drawings]

FIG. 1 is a block diagram of a green sheet laminating apparatus showing an embodiment of the present invention, FIG. 2 is an enlarged view of the main parts of the apparatus, and FIGS. 3 to 6 are explanatory diagrams of each process of the apparatus. 1... Punch, 2... Die, 3... Knockout plate, 4... Suction pipe, 6... Rod heater, 7... Temperature measuring element.

Claims (1)

[Claims] 1. A sheet lamination method that is characterized by mechanically aligning sheets one by one, cutting the outer periphery to a predetermined size and laminating the sheets, and then vacuum-treating the laminated sheets while heating and pressurizing them.