JP2803653B2 - Thin plate crack detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting cracks generated in a thin plate obtained by firing ceramic powder, for example, and more particularly to an apparatus which is excellent in versatility and is not restricted by a work place, and is capable of improving the safety of workers. The present invention relates to a thin plate crack detecting device which can be secured and has a simple structure.

[0002]

2. Description of the Related Art Ceramic materials such as alumina and silicon carbide have excellent properties such as corrosion resistance and abrasion resistance as compared with metal materials, and are materials that achieve improved performance and extended life of various products. As widely used. However, ceramic materials have a drawback in that machining such as plastic working is more difficult than metal materials. For this reason, the ceramic molded article is formed by molding the powder, which is the raw material, so as to be as close as possible to the shape and dimensions of the molded article, and the machining, such as cutting and polishing, is applied as lightly as possible.

However, depending on the conditions of machining such as cutting and grinding, cracks, which are minute cracks, occur in the ceramic molded product. Since the cracks serve as starting points where stress concentration occurs, not only the mechanical strength is reduced, but also the electrical characteristics of ceramic electronic components are deteriorated. Therefore, cracked ceramic molded products are inspected so as not to be shipped. However, since the cracks are fine, it is difficult to inspect for the presence of the cracks.

In order to solve such problems, cracks generated in ceramic molded articles can be easily detected by Japanese Patent Application Laid-Open Nos. 60-202336 and 62-113044. Is disclosed.

[0005] The invention disclosed in Japanese Patent Application Laid-Open No. 60-202336 discloses a method in which a coloring liquid is adhered to a ceramic molded article, an excess coloring liquid is thereafter removed, and the powder is adhered to the ceramic molded article. Is detected. If a crack occurs in the ceramic molded product, the coloring liquid remains in the crack, and the powder adhering to the ceramic molded product is colored by the coloring liquid, so that the crack is easily detected. Moreover, even if the ceramic molded product is black, visual observation is easy, and there is no problem that the user must work in a dark room.

On the other hand, the invention disclosed in Japanese Patent Application Laid-Open No. 62-13044 discloses a method in which hydrogen or helium gas is diffused and permeated into the members of a ceramic molded product, and the amount of gas released from the surface of the ceramic molded product is reduced. This is a method for detecting cracks measured by a sensor. If a large amount of gas is detected, it can be determined that a crack has occurred in the ceramic molded product.

[0007]

Problems to be Solved by the Invention
The invention disclosed in Japanese Patent Publication No. 36 is to detect the occurrence of cracks by applying a coloring liquid to a ceramic molded product. However, if the coloring liquid is applied after the circuit is formed on the thin plate, since the coloring liquid is an organic solvent, a trouble such as a short circuit of the circuit on the thin plate occurs.

Further, the invention disclosed in Japanese Patent Application Laid-Open No. Sho 62-113044 is to detect whether cracks have occurred in a ceramic molded product by using gas. However, since hydrogen or the like is used as the gas, not only the location of the detection operation is restricted, but also a problem arises that the safety of the operator must be sufficiently considered.

The present invention has been made in view of the above problems, has excellent versatility, can secure the safety of workers without being restricted by a work place, and has a simple structure. An object of the present invention is to provide a crack detection device.

[0010]

According to the present invention, there is provided an apparatus for detecting cracks in a thin plate, which has an air supply hole and an intake hole, and a table on which a thin plate is placed on the surface, and which blows air from the air supply hole of the table toward the back surface of the thin plate. Air supply means for sending out air, air suction means for sucking air in the suction hole of the table, and pressure measurement means for measuring pressure between the air suction means and the suction hole. It is.

When a thin plate crack is detected by the thin plate crack detecting device of the present invention, first, the thin plate is placed on the surface of a table, and air is sent from an air supply hole toward the back surface of the thin plate by air sending means. The broken sheet is in a state of being separated into multiple pieces and the weight of each piece is light,
It floats upward by the sent air.

In this state, when the air in the suction hole is suctioned by the air suction means, the broken thin plate is separated, so that the suction hole communicates with the atmosphere. Therefore, the degree of vacuum between the air suction means and the suction hole measured by the pressure measurement means does not increase and the pressure becomes the atmospheric pressure, so that it can be determined that the thin plate is broken. When the pressure between the air intake means and the intake hole is a negative pressure, it can be determined that the thin plate is not broken.

When air pressure adjusting means and air flow rate adjusting means are provided between the air sending means and the air feed hole, the air sent from the air feed hole is adjusted according to the size, mass, etc. of the thin plate. can do.

[0014] In order to separate each of the cracked thin plates outwardly, the air supply holes of the table are formed at positions corresponding to both ends of the thin plate along the scribe direction of the thin plate, and outwardly toward the tip. Preferably, it is formed inclined.

[0015] The air intake means includes, for example, a first flow path formed so that a central portion is narrowed, and a second flow path communicating with the central portion of the first flow path. By sending air from the air sending means, the air in the air inlet may be sucked into the second flow path,
Further, a vacuum pump may be used.

[0016]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIGS. FIG. 1 is a plan view of a thin plate crack detecting device according to the present invention, FIG. 2 is a partial cross-sectional perspective view of the thin plate crack detecting device according to the present invention, and FIG. 3 is a cross-sectional diagram showing the internal structure of the vacuum generating device. FIG. 4 is a plan view showing a state of a thin plate when the thin plate crack detecting device according to the present invention is used.

The crack detecting device according to the present invention has a rectangular table 2 on which a thin plate 1 formed of, for example, a ceramic material is placed. The table 2 has an air inlet 10 and an air inlet 20.
Are formed.

As shown in FIG. 1, the air supply hole 10 of the table 2 is composed of a plurality of small holes formed along the scribe direction (arrow direction) of the thin plate 1 and is opposed to the left and right at a predetermined interval. Are located. Further, as shown in FIG. 2, the air supply holes 10 are formed so as to be inclined outwardly toward the tip in order to separate the separated pieces of the broken thin plate 1 outwardly.

Inside the table 2, each air supply hole 10
Are branched from one central hole 21 and communicate with each other. A pipe 22 is connected to the center hole 21. An air generator 23 for generating air from the upstream side, a pressure regulator 24 for adjusting the pressure of air, and an air flow regulator 25 for adjusting the flow rate of air are connected to the pipe 22. The air sent from the air supply hole 10 is adjusted by the air pressure regulator 24 and the air flow regulator 25 according to the size, mass, and the like of the thin plate 1.

The intake holes 20 are formed as long holes which are closed on both sides of the thin plate 1, and are arranged to face each other at a predetermined interval vertically. A vacuum generator 1 for evacuating the air in the suction holes 20 of the table 2 is provided in the suction holes 20.
2 are connected via a pipe 11.

As shown in FIG. 3, inside the vacuum generator 12, a first flow path 30a formed so as to have a narrow center portion, and a second flow path communicating with the center portion of the first flow path 30a. A channel 30b is formed. The compressed air sent from the air generator 23 is sent from the hole 30c to the first flow path 30a, and is exhausted to an exhaust device 31 (see FIG. 2) such as a muffler through the hole 30d. Thereby, the air in the intake hole 20 is sucked into the second flow path 30b through the hole 30e.

As the vacuum generator 12, a vacuum pump or the like is used. In this case, the air generator 23
No connection is required.

The pipe 11 is connected to a pressure gauge 13 for measuring the pressure between the vacuum generator 12 and the suction hole 20. The magnitude of the negative pressure in the intake hole 20 is measured by the pressure gauge 13.

When the intake port 20 is completely closed by the thin plate 1, a negative pressure is generated in the intake port 20, and the pressure gauge 13 shows a large value. However, the thin plate 1 is cracked and the intake holes 20
Is no longer blocked, the pressure gauge 13 shows a low value because no negative pressure is generated in the intake hole 20.

Next, a method for detecting a crack in the thin plate 1 by the thin plate crack detecting device according to the present invention will be described.

First, the thin plate 1 is placed on the table 2 so that the periphery thereof closes the air supply hole 10 and the air intake hole 20. Next, the air generated from the air generator 23 is supplied into the center hole 21 via the air pressure regulator 24 and the air flow regulator 25, and is sent out from each air supply hole 10 toward the back surface of the thin plate 1. The thin plate 1 cracked in the scribe direction (the direction of the arrow in FIG. 1)
Although the total weight is the same, the weight of each piece is light because it is separated into a plurality. Therefore, each piece of the thin plate 1 floats upward by the sent air, and the air supply hole 10 is formed to be inclined outward toward the tip, so that the air is sent outward and the air is sent outward. As shown in FIG. 4, each of the thin plates 1 is separated outwardly.

In this state, when the air in the suction hole 20 is sucked in by the vacuum generating device 12, the broken thin plate 1 is separated, so that the suction hole 20 and the atmosphere communicate with each other at the portion A in FIG. become. Accordingly, since the degree of vacuum between the vacuum generator 12 and the suction hole 20 measured by the pressure gauge 13 does not increase and the pressure becomes the atmospheric pressure, it can be determined that the thin plate 1 is broken. When the pressure between the vacuum generator 12 and the suction hole 20 is a negative pressure, it can be determined that the thin plate is not broken.

It is to be noted that a display device for displaying the degree of cracking of the thin plate 1 according to the pressure in the intake hole 20 measured by the pressure gauge 13 may be provided. Further, an alarm device for issuing an alarm when a crack in the thin plate 1 is detected may be provided.

According to the apparatus for detecting cracks in a thin plate according to the present invention, the vacuum generator 12 and the intake hole 20 are controlled by the pressure gauge 13.
Since the crack of the thin plate 1 can be detected only by measuring the pressure between the thin plate 1 and the surface state of the thin plate 1, the versatility can be improved without changing the surface state of the thin plate 1.

Further, compared to the conventional apparatus, the safety of the worker can be secured without being restricted by the work place.

Furthermore, since the structure is simple, the manufacturing cost can be reduced.

The present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims. For example, the present invention can be implemented even if the thin plate 1 is not rectangular but circular. Further, the thin plate 1 is not limited to a ceramic molded product, but can be applied to other thin plates.

The air used in the present invention may be any gas as long as it does not adversely affect the thin plate 1.

[0034]

According to the apparatus for detecting cracks in a thin plate according to the present invention, the cracks in the thin plate can be detected only by measuring the pressure between the air suction means and the suction hole by the pressure measuring means. Is not changed, and the versatility can be improved.

Further, compared to the conventional apparatus, the work place is not restricted and the safety of the worker can be ensured.

Further, since the structure is simple, the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a thin plate crack detection device according to the present invention.

FIG. 2 is a partial cross-sectional perspective view of the thin plate crack detection device according to the present invention.

FIG. 3 is a sectional view showing the internal structure of the vacuum generator.

FIG. 4 is a plan view showing the state of a thin plate when the thin plate crack detection device according to the present invention is used.

[Explanation of symbols]

 1: thin plate 2: table 10: suction hole 12: vacuum generator (air suction means) 13: pressure gauge (pressure measurement means) 20: suction hole 23: air generation device (air sending means) 24: pressure regulator (air) Pressure adjusting means) 25: Flow regulator (air flow adjusting means)

Claims (5)

(57) [Claims] 1. A table having an air supply hole and an air intake hole, on which a thin plate is placed on the surface, air sending means for sending air from the air supply hole of the table toward the back surface of the thin plate, And a pressure measuring means for measuring a pressure between the air suction means and the air intake hole. 2. The apparatus according to claim 2, wherein said air delivery means and said air supply hole are provided between:
2. The thin plate crack detecting device according to claim 1, further comprising an air pressure adjusting unit and an air flow adjusting unit. 3. An air supply hole of the table is formed at a position corresponding to both ends of the thin plate along a scribe direction of the thin plate, and is formed so as to be inclined outwardly toward a front end. The thin plate crack detecting device according to claim 1 or 2, wherein: 4. The air intake means includes a first flow path formed so that a central portion is narrowed, and a second flow path communicating with the central portion of the first flow path. 4. The thin plate according to any one of claims 1 to 3, wherein air from the air sending means is sucked into the second flow path by feeding air from the air sending means to the thin plate. Crack detection device. 5. The apparatus for detecting cracks in a thin plate according to claim 1, wherein said air suction means is a vacuum pump.