JPH0476282B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for forming kerfs in an unfired ceramic sheet or the like.

[Prior Art] Square chip parts such as chip resistors and chip capacitors are made by cutting grooves b of a predetermined depth in an unfired ceramic sheet a, a so-called green sheet, as shown in FIG. After printing a conductor base or a resistor base on the surface of the sheet a, the sheet a is introduced into a furnace and fired, and is divided into individual chips along the cut grooves as boundaries.

Conventionally, as a method for cutting the above-mentioned grooves b, as shown in FIG. 5, a means has been implemented in which the grooves are formed in the ceramic sheet a using a disc-shaped cutter 1 that rotates at high speed. In this method, while rotating the cutter 1 at high speed, the base 3 on which the sheet a is mounted
The cutter 1 is moved up and down against the cutter 1 and reciprocated in the direction along the blade to form a lattice-shaped cut groove b as shown in FIG.

Another method of forming the kerf b is to press the cutter 1 having a linear cutting edge against the sheet a and move the cutter 1 along the cutting edge to form the kerf b.

[Problems to be Solved by the Invention] Particularly in the former method, since the cutter 1 is moved up and down each time a groove is formed, the depth of the cut groove b to be formed tends to vary. If the depth of the kerf b varies, there will be problems such as the condition of the fractured surface not being constant when dividing after firing and the dimensions of the individual chips varying.

On the other hand, in the case of the latter method, in which cutting is performed from end to end without moving the cutter 1 up and down, the cut grooves are made without leaving the periphery of the sheet a, so the cut grooves B on the peripheral part are cut before dividing. Peeling is likely to occur, making handling of the sheet a after the grooves b have been formed and the firing process difficult.

It is an object of the present invention to solve the above-mentioned problems in conventional kerf forming means.

[Means for Solving the Problems] The structure of the present invention will be explained with reference to the reference numerals in FIGS. The center of rotation of the cutter 11, in which the cutting edge 12 is formed only within the angle of , is held at a constant height with respect to the sheet. Then, after moving the sheet a directly below the cutter 11 with the blade portion 12 facing upward, the cutter 11 is rotated about the rotation center, and
The blade portion 12 is made to cut into the sheet a. Furthermore, while keeping the cutter 11 fixed, move the sheet a to the cutting edge 1.
After making the cut groove by moving along the direction of 2,
The cutter 11 is rotated again to return its cutting edge 12 upward, and the sheet a is taken out from under the cutter 11, thereby forming a kerf.

Next, in the kerf forming device of the second invention for carrying out the method, the cutting edge 12 is formed only in a part of the angle sandwiching the central axis of the rotating shaft 14, and the cutting edge 12 is formed around the rotating shaft 14. Cutter 11 that can be rotated freely
and a base 13 having a flat upper surface provided below the cutter 11, and the upper surface of the base 13 on which the sheet a is mounted is kept at a constant distance from the rotating shaft 14 in a constant direction. It is meant to be moved.

[Operation] In the above method, the cut grooves b are formed in the sheet a while maintaining the center of rotation of the cutter 11 at a constant height from the upper surface of the base 13, so that the cut grooves b are formed to have a constant depth. Further, by rotating the cutter and moving the blade portion 12 up and down, it is possible to leave the cut groove b in the peripheral portion of the sheet a without making it, as shown in FIG. 7.

Further, in the above-mentioned apparatus, the above-mentioned method can be carried out reliably and easily by rotating the cutter 11 around the rotating shaft 14 and reciprocating the base 13.

[Example] Next, an example of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 3, on a base 13 having a flat upper surface on which the sheet a is mounted, a rotating shaft 14 is held at a constant height from the upper surface, and a cutter 11 is fixed to this. ing. This cutter 11 has a blade portion 12 formed only at a portion of about 30 degrees across the central axis of the rotating shaft 14, and the diameter R of the blade portion 12 is set larger than the diameter r of the other portions. These cutters 11 are fixed to the rotating shaft 14 at regular intervals via spacers 15, and rotate about the central axis of the rotating shaft 14. In addition, the third
As shown in the figure, due to the rotation of the rotating shaft 14,
When the blade part 12 is lowered toward the base 13, the height of the blade part 12 from the upper surface of the base 13 is set lower than the thickness of the sheet a.

The base 13 has a hard and flat upper surface, on which the seat a is mounted and reciprocated in the directions indicated by arrows in FIGS. 1 and 3. At this time, the distance from the central axis of the rotating shaft 14 to the upper surface of the base 13 is always constant.

When making a cut groove b on a sheet a using this device, first, as shown in FIGS. and move it directly below the cutter 11. Next, as shown in FIG.
Rotate it so that it hits the upper surface of the sheet a, and while keeping the cutter 11 fixed here, move the base 13,
The upper surface side of the sheet a is cut with the blade part 12 to form a cut groove b.

Next, the base 13 is stopped, and the rotating shaft 14 is rotated approximately 180 degrees to return the blade portion 12 to the position shown in FIG. In this state, sheet a is taken out from under the cutter 11. By repeating the above operations, the required number of grooves b can be formed on the sheet a. Note that when forming the lattice-shaped kerf b as shown in FIG. 7, one row of the kerf b
After forming the sheet a, the direction of the sheet a is changed by 90 degrees and placed on the base 13, and the other row of grooves b are formed in the same manner.

The third example shows various embodiments of the cutter 11 used in the device. In the same figure, a shows the blade part 1.
The center of the curve of the outline of No. 2 is shifted from the center axis of the rotating shaft 14, and the outline of the blade portion 12 is formed to be gentle. In Figure b, the blades 12 are provided at three locations at 120° intervals, and the cutter 11 is rotated at a 45° angle around the rotation axis 14.
It is designed to rotate at intervals. Figure c
The blade portions 12 are provided at four locations at 90° intervals, and the cutter 11 is rotated around a rotating shaft 14 at 45° intervals. In the figure d, three blade parts 12 with different diameters R are provided, and the blade edge 1 has different curvatures.
2 can be used appropriately.

FIG. 4 shows various shapes of the starting point of the blade portion 12. These are appropriately selected and used depending on the type of sheet a.

[Effects of the Invention] As explained above, according to the present invention, the kerf b of a constant depth can be formed in the sheet a, and variations in the depth of the kerf b can be eliminated.

[Brief explanation of the drawing]

1a and 1b are schematic side and front views of a kerf forming device showing an embodiment of the present invention; FIG. 2 is a side view showing a state in which the cutter has been rotated approximately 180 degrees from the state in FIG. 1; Figure 3 is a side view showing the various shapes of the cutter, Figure 4 is an enlarged view and front view of main parts showing the shape of the starting point of the blade of the cutter, and Figures 5 and 6 are conventional examples of kerf forming devices. FIG. 7 is a schematic side view showing the sheet, and FIG. 7 is a plan view of the sheet. DESCRIPTION OF SYMBOLS 11... Cutter, 12... Blade part, 13... Base, 14... Rotating shaft, a... Sheet, b... Cutting groove.

Claims (1)

[Claims] 1. In a method of forming a cut groove on a sheet, the center of rotation of a cutter 11, in which the cutting edge 12 is formed only at a part of the angle between the center of rotation, is set at a constant height with respect to the sheet a. After holding the cutter 11 and moving the sheet a directly below the cutter 11 with the blade 12 facing upward, the cutter 11 is rotated about the rotation center and the blade 12 is cut into the sheet a, In this state, with the cutter 11 fixed, the sheet a is relatively moved along the direction of the cutting edge 12 to make a cut groove, and then the cutter 11 is rotated again to return the cutting edge 12 upward, and the sheet a is moved into the cutter. 1. A method for forming grooves in a sheet, characterized in that the grooves are taken out from below. 2. An apparatus for forming kerfs on a sheet includes a cutter 11 in which the cutting edge 12 is formed only in a part of the angle sandwiching the central axis of a rotating shaft 14 and is rotatable around the rotating shaft 14, and the cutter 11. The base 13 has a flat upper surface provided under the rotating shaft 11, and the upper surface of the base 13 on which the seat a is mounted is moved in a fixed direction while maintaining a fixed distance from the rotating shaft 14. Characteristic sheet kerf forming device.