JPS62181810A - Boring condition inspector - Google Patents

Abstract

PURPOSE:To enable the direct monitoring of bored condition by irradiating X-ray onto a work having through-holes bored therethrough and producing a visible optical image on a fluorescent board then deciding the breaking condition of tool on the basis of said optical image. CONSTITUTION:Through-holes 2 are bored from the upper face 5 of a substrate 3 by means of a drill 1. A portion 7 for irradiating X-ray is positioned at an nit area in the through-hole section. X-ray 6 is passed through the substrate 3 then received at a section 10 for X-ray inspection comprising a fluorescent board 9 thereafter collected 11 and sent to a photographing section 12. On the basis of an image signal S1 fed from the photographing section 12, a section 14 for deciding the breaking will perform comparison with a normal pattern through a pattern matching method and decide the breaking of tool for subsequent replacement thereof by the operator.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a drilling condition inspection device that can automatically detect breakage of a drill or the like.

[Technical background of the invention and its problems]

As electronic devices become lighter and smaller, the circuit boards used therein are becoming more compact. Naturally, in this high-density circuit board, the circuit elements to be mounted are also downsized, and various holes formed on the printed circuit board, such as holes for mounting them, are also inevitably downsized. In other words, the conventional diameter was 9.8m.
What was m.

0.3 m, 0.1 txm.

Normally, this printed circuit board is drilled using an automatic drilling machine that uses a drill, and if a breakage of the drill is detected, the drilling process is immediately stopped. Conventionally, there are two types of detectors for detecting breakage of a drill: (1) one that detects changes in cutting torque due to breakage; (2) For example, an AE sensor is attached to the spindle head on which the drill is attached, and the AE sensor (c) A method that irradiates the drill with the light beam emitted from the projecting head through an optical fiber, and optically detects the breakage of the drill from the amount of light incident on the light receiving head. There are some for each inn.

However, these conventional detectors have a limit of detecting a breakage of a drill with a diameter of 0.8 mm, and cannot reliably detect a breakage of a drill smaller than that.

In other words, as the diameter of the drill decreases, the cutting torque and AE signal themselves become smaller, and the S/N ratio decreases, making it impossible to detect what is detected from changes in cutting torque and signals output from the path sensor. In addition, for optical detection, the light emitted from the tip of the optical fiber is diffused at an angle of about 60', so if the diameter of the drill becomes small, the light emitted from the tip will be received regardless of whether there is a drill or not. It enters the head, making it impossible to detect drill breakage.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances.

It is an object of the present invention to provide a drilling condition inspection device that can automatically and accurately detect the quality of drilling by a small-diameter drill.

[Summary of the invention]

A workpiece with a through hole is irradiated with X-rays and the transmitted X
A line image is obtained as a visible light image on a fluorescent plate, and the broken state of the tool for machining the through hole is determined based on this X-ray image.

[Embodiments of the invention]

An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 relates to the permeation status inspection device of this embodiment. This device has a through hole (2) in a predetermined position with a drill (1).
A holding part (4) that holds and positions the edge of the substrate (3) to be drilled, and one main surface (5) of the substrate (3) held by this holding part (4). An X-ray irradiation section (7) is arranged on the side of the substrate (3) and irradiates the X-rays (6) almost orthogonally to the main surface (5), and an X-ray irradiation section (7) is arranged on the other main surface (8) side of the substrate (3). (3) A fluorescent plate (
9) as the main part, and a fluorescent plate (9).
) on the opposite side of the substrate (3).
), which receives the X-ray image and focuses it on a predetermined position, and receives the X-ray image focused by this focusing optical system and converts it into an image signal. For example, IT
An image pickup unit such as a V camera or a CCD camera, an image memory unit that inputs and temporarily stores the image signal output from the image pickup unit, and an image signal output from the image memory unit A breakage determination unit α4, which includes, for example, a microcomputer, determines whether or not the drill (1) is broken based on the
, the determination result by the breakage determination unit a and the imaging unit 0
The display unit (15), such as a cathode ray tube, displays the X-ray image taken by the drill. It is connected to the NC section (I7) that numerically controls the driving NC drilling machine (to.

In the breakage determination section Oa, multiple normal patterns are determined for each breakage inspection performed sequentially over multiple stages (see Figure 2).
is stored. These normal pattern switching operations are as follows:
This is done by a switching signal SC from the N0 section (I7). Further, the irradiation area of the substrate (5) with the X-rays (6) is only a part, for example, 1/to of the substrate (6). Therefore, when the inspection of one irradiation area is completed, the holding part (4) positions the next irradiation area so that it is directly below the X-ray irradiation part (sword).

Next, the operation of the clarity status inspection device having the above configuration will be described.

First, the drilling machine (16
) and the holding part (4) are operated, and the drill (1) continuously perforates the substrate (3) using the irradiation area as one unit.

A through hole (2)... is bored. Then, when the drilling operation of this unit area is completed, the unit area where the drilling has been completed is positioned directly below the X-ray irradiation unit (7) by the holding unit (4). Next, the main surface (5) of the substrate (3) is irradiated with X-rays (6) from the X-ray irradiation section (7). Then, the X-ray (6) passes through the substrate (3, 1) and passes through the fluorescent plate (9).
The light is received as an X-ray image (see Figure 3). At this time.

The X-ray intensity corresponding to the substrate (3) is much weaker than the X-ray intensity that has passed through the through holes (2). Therefore, as shown in FIG. 3, only the portions α to . . . corresponding to the through holes (2) . . . shine brightly. Such an X-ray image is captured by the imaging unit α through the optical system αυ.

An image signal SI indicating an X-ray image is output to the image memory section (13).Then, from this image memory section (13).

An image signal SK representing the X-ray image shown in FIG. 3 is output to the breakage determining section (14). In the breakage determination section α, a comparison process is performed between the X-ray image of the broken unit area shown in FIG. 3 and the normal pattern shown in FIG. 42 using a beam matching method or the like. As a result, if a discrepancy is found between the two, that is.

Through hole (2)...If there is no brightly emitting part (13...) in the area corresponding to the planned drilling area, please
) is determined to be broken, a breakage detection signal SD is output from the breakage determination section α4 to the N0 section α7, the drilling operation is interrupted by the NCC pole handle, and the drill (1) is replaced. However, if no discrepancy is found between the X-ray image and the normal pattern, it is determined that "drill (1) is normal" and N
C. The perforation process is continued, and the same operation is repeated for each unit area.

As described above, since the tool breakage detection device of this embodiment directly monitors the drilling state of the through holes (2) using X-rays, the inspection accuracy is improved. In particular, even holes with a diameter of 0.8 mm or less, which are difficult to detect with visible light, can be checked with certainty, improving the accuracy of drill breakage detection. Furthermore, since it is possible to directly monitor the condition of the through holes (2), it has the advantage that it is possible to check not only drill breakage, but also the wear state and lateral distortion of the drill.

In addition, although the above example illustrates the breakage of the drill,
Other drilling tools such as reamers, taps, etc.) can also be used. In addition, the present invention can also be applied to detection of breakage of a punch during punch press processing of plate materials.

〔Effect of the invention〕

Since the drilling condition inspection device of the present invention directly monitors the drilling condition using X-rays, it improves the detection accuracy of tool breakage, is easily adaptable to automation, and leads to improved inspection efficiency. especially.

For example, it is particularly effective in detecting tool breakage for drilling micro holes with an inner diameter of 0.8 mg or less. In addition to detecting breakage, the present invention has the advantage that it is possible to monitor the wear state of the hole diameter management tool.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a perforation condition inspection apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing a normal pattern, and FIG. 3 is a diagram showing an X-ray image. (1) Nitrile, (2): Through hole. (3) Two substrates (workpieces), (7): X-ray irradiation section. αo):X#,! Detection section, α2: Imaging section. αa: Breakage determination section. Agent Patent Attorney Noriyuki Chika Yudo Kikuo Takehana Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] an X-ray irradiation unit that irradiates a workpiece having a through-hole drilled with X-rays in substantially the axial direction of the through-hole; and an X-ray irradiation unit provided on the opposite side of the X-ray irradiation unit across the workpiece. an X-ray detection unit that converts the X-rays that have passed through the through-hole into a visible image; a condensing optical system that condenses the visible image obtained by the X-ray detection unit at a fixed position; It includes an imaging unit that captures a visible image focused by an optical system and converts it into an image signal, and a breakage determination unit that determines whether the tool for performing the drilling process is broken based on the image signal output from the imaging unit. A confucius status inspection device characterized by: