JP2987810B2 - Stamping ceramic green sheet and die for punching ceramic green sheet - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a punched ceramic green sheet manufactured by punching a ceramic green sheet having a thickness of about 0.5 mm to 1.5 mm, and an apparatus for producing the sheet. .

[Prior Art] A ceramic green sheet is an unsintered ceramic body formed by mixing a ceramic powder with a sintering aid and a binder, and forming the same into a sheet shape, and usually has a thickness of about 0.5 mm to 1.5 mm.

In order to prevent chipping during transportation and process transportation, there is known a technique in which corners between a side surface and upper and lower surfaces of a ceramic substrate are rounded by barrel processing.

[Problems to be solved by the invention] However, such a technique has the following disadvantages.

(A) Barrel processing is costly and time consuming.

(A) Physical properties change on the ceramic surface, such as a decrease in adhesion strength with the thick film paste.

An object of the present invention is to provide a punched ceramic green sheet which becomes a ceramic substrate that is unlikely to be chipped during transfer, and to provide a ceramic green sheet punching die for producing the punched sheet.

[Means for Solving the Problems] To achieve the above object, the present invention employs the following constitutions.

(1) The corners of the side and the upper and lower sides are rounded, and the center of the side is
A ceramic green sheet is punched out so as to swell up to 15 μm.

(2) A fixed lower punch, a frame-shaped stopper which is fitted into the lower punch with play and is displaced in a punching direction from a substantially flush position at the time of punching, and a ceramic green sheet is pressed against the lower punch at the time of punching. A ceramic green sheet punching die, comprising: an upper punch to be cut; and a frame-shaped die which is fitted into the lower punch while displacing the stopper to punch the ceramic green sheet. The clearance with the thickness of the ceramic green sheet
An R process with a radius of curvature of 0.03 mm to 0.1 mm and a radius of curvature of 0.5% to 2% was performed on the punching edge of the die.

[Functions and Effects of the Invention] <Regarding Claim 1> By firing the punched ceramic green sheet, a ceramic substrate is obtained in which chipping does not extremely occur during transportation and process transportation.

Since the punching of the ceramic green sheet and the end face processing are performed simultaneously, the manufacturing cost is low and the time required for the manufacturing can be reduced.

After the punched sheet is fired, the surface is not processed, so that the physical properties of the ceramic surface do not change.

In addition, the reason why the center of the side is set to 15 μm is that if more bulge is desired, the clearance between the die and punch for punching becomes too small, and the ceramic green sheet during production may be chipped or cracked. To do that.

The ceramic substrate obtained by firing the ceramic green sheet having a shape in which the center of the side surface is swelled has chipping resistance in a drop impact test, and can prevent chipping of the side surface during transportation and during process transportation.

<Regarding Claim 2> (Operation) A ceramic green sheet is placed across the lower punch and the stopper.

The upper punch and the die descend, but the upper punch stops by pressing the ceramic green sheet against the lower punch.

The die performs punching of the ceramic green sheet by fitting into the lower punch while displacing the stopper substantially at one position on the surface in the punching direction.

The narrow clearance between the die and the lower punch has the effect of making the lower side of the cross-sectional shape of the punched sheet long and trapping the corner of the upper surface.

Further, when a configuration having a punching edge R is added, the skirt of the punched sheet is rounded.

(Effect) The clearance between the die and the lower punch is 0.5% to 2% of the thickness of the ceramic green sheet, and the radius of curvature is 0.03mm.
A radius of ~ 0.1 mm is applied to the die punching edge. For this reason, the ceramic green sheet can be punched out so that the central portion swells (0 μm to 15 μm) and the upper and lower surfaces have a cross-sectional shape with rounded corners. If this punched sheet is fired to form a ceramic substrate, chipping during transfer hardly occurs.

The reason for limiting the numerical value is that if the clearance is less than 0.5%, the die and lower punch cannot be fitted, and if it exceeds 2%, the cross-sectional shape of the punched sheet becomes trapezoidal with long upper and lower sides and the upper surface Corners are sharp. Also, the radius of curvature is 0.
If it is less than 03 mm, the effect of rounding the hem will be inferior and 0.1 m
If it exceeds m, burrs are likely to appear.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 2, the punching die A includes a lower punch 1 fitted with a frame-shaped stopper 2 and, at the time of punching, an upper punch 4 for holding the ceramic green sheet 3 and a frame-shaped die 5 for punching. .

The upper part of the lower punch 1 related to punching presents a square pole, and the upper surface thereof is made of a cemented carbide 11. The lower punch 1 is placed on the table holder 12 and fixed with fixing bolts.
Fixed at 13.

The stopper 2 is fitted into the upper portion of the lower punch 1 with a play s of 0.1 mm, and is adjusted to the same height as the lower punch 1 when the ceramic green sheet 3 is laid by the adjusting nut 21 and the spring 22. Has been.

The ceramic green sheet 3 is manufactured using alumina as a main raw material and has a thickness of 1.0 mm. This sheet 3
It is laid so as to straddle the fitting portion between the lower punch 1 and the stopper 2.

The upper punch 4 includes a lower punch 1
It has a quadrangular prism shape corresponding to the upper part of. The upper punch 4 includes an upper punch holding pin 41, an adjustment spring 42,
The punch holder 56 is elastically provided with a spring holding bolt 43.

The die 5 has a portion related to punching formed of a cemented carbide 51, and the punching edge 52 is subjected to a rounding process with a radius of curvature of 0.05 mm. The die 5 is connected to a ball bush 53, a base plate 54, a pin base 55, and a punch holder 56. In this embodiment, the gap between the die 5 and the lower side surface 44 of the upper punch 4 is 0.01 mm, and the die 5 and the lower punch 1
The clearance t at the time of fitting is 0.01 mm.

Next, the punching of the ceramic green sheet 3 using the punching die A will be described.

(1) The ceramic green sheet 3 is placed across the lower punch 1 and the stopper 2.

(2) The die 5 includes a ball bush 53, a base plate 54,
It moves downward together with the pin base 55 and the punch holder 56. At this time, the upper punch 4 is also lowered by pressing the upper lower end surface 45 against the upper end surface 57 of the die 5 by the spring 42.

(3) First, the upper punch 4 is the ceramic green sheet 3
However, the operation is stopped when the ceramic green sheet 3 is pressed against the lower punch 1 by the action of the spring 42.

(4) The die 5 is fitted into the lower punch 1 while displacing the stopper 2 to punch out the ceramic green sheet 3.

Next, a description will be given of the punched ceramic green sheet 30 manufactured as described above, together with its effects.

The punched ceramic green sheet 30 has a cross-sectional shape as shown in FIG. 4, and the corners of the side surface 31 and the upper and lower surfaces 32, 33 are rounded. The center 34 of the side surface 31 swells up to 15 μm.

The ceramic substrate (not shown) manufactured by sintering the sheet 30 has a chipping resistance equal to or higher than that obtained by subjecting the corners between the upper and lower surfaces and the side surfaces to R processing of 0.02 mm to 0.04 mm by barrel processing. Drop impact test).

Next, a description will be given of the results of experiments conducted by manufacturing various samples for each numerical range of the clearance t between the die 5 and the lower punch 1 and the radius of curvature of the punching edge 52 of the die 5.

(Regarding the clearance t) The clearance t between the die 5 and the lower punch 1 is set to exceed 2% of the thickness of the ceramic green sheet 3 (however, the R edge of the punching edge 52 is not processed).
As shown in FIG. 5, the sheet 100 is punched out so that the cross-sectional shape becomes a trapezoid having long upper and lower sides. Also, the corner 111 of the upper surface 110 tends to be sharp. The dimensions u at 4%, 5% and 10% are 10 μm to 40 μm and 0 μm to 15 μm, respectively.
μm, 20 μm to 45 μm. Also, the clearance t
If it is less than 0.5%, it is difficult to fit the lower punch 1.

(About R processing of the punching edge 52) When the radius of curvature was less than 0.03 mm, the hem was hardly rounded. When it exceeded 0.1 mm, burrs occurred frequently.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a die for punching a ceramic green sheet according to an embodiment of the present invention, and FIGS. 2 and 3 are partial sectional views of the die. FIG. 4 is a sectional view of a punched ceramic green sheet produced by the mold. FIG. 5 is a cross-sectional view of a punched ceramic green sheet manufactured under the conditions stipulated by the constitution of the present invention. In the figure, 1 ... lower punch, 2 ... stopper, 3 ... ceramic green sheet, 4 ... upper punch, 5 ... die,
30 …… Punched ceramic green sheet, 31 …… Side, 32
... top surface, 33 ... bottom surface, 34 ... center, 52 ... punching edge, A ... ceramic green sheet punching die, s ...
… Play, t …… clearance

Continuation of front page (56) References JP-A-49-125408 (JP, A) JP-A-56-71712 (JP, U) JP-A-64-57012 (JP, U)

Claims (2)

(57) [Claims] 1. A punched ceramic green sheet in which corners of a side surface and upper and lower surfaces are rounded, and a center of the side surface is swollen up to 15 μm. 2. A fixed lower punch, a frame-shaped stopper which is fitted into the lower punch with play, and is displaced in a punching direction from a substantially one position at the time of punching, and a ceramic green sheet is punched at the time of punching. A ceramic green sheet punching die, comprising: an upper punch that presses the die; and a frame-shaped die that is fitted into the lower punch while displacing the stopper to punch the ceramic green sheet. A ceramic green sheet characterized in that the clearance with the lower punch is 0.5% to 2% of the thickness of the ceramic green sheet, and that a radius of curvature of 0.03 mm to 0.1 mm is rounded to the punching edge of the die. Die for punching.