JPS61132814A - Marking inspecting method - Google Patents

Abstract

PURPOSE:To execute a detection at a high speed by moving a member which has made a paint adhere to the ourside peripheral surface of a transparent columnar body, in the direction orthogonal to its axis, irradiating a light to a fixed position on its locus, detecting a refracted light by the member, and discriminating whether making is good or not. CONSTITUTION:Marking 4 is formed by applying at a prescribed interval a paint of a prescribed width onto the outside peripheral surface of a glass sleeve 1 of a diode 5, and a light source 7 and a photodetecting sensor 8 are placed at the upper fixed position of a moving locus 6 and the lower fixed position, respectively. In this state, a luminance distribution pattern generated along the axial direction of the sleeve 1 by the light source 7 is detected by the sensor 8, and from an output variation of the sensor 8 caused by a variation of its pattern, failure of the marking 4 is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) The present invention relates to a method for detecting markings such as color hoods formed on the outer peripheral surface of a transparent cylindrical member at high speed.

one shift to the skin An example of an electronic component is a glass-sealed diode.

This will be explained with reference to FIGS. 7 and 8.

In the figure, 1 is a glass sleeve (transparent hollow cylinder).
Inside, a diode pellet 3 is sandwiched between a pair of slug leads F2.2, and the inner circumferential surface of the sleeve 1 and the outer circumferential surface of the slug lead 2 are welded and sealed airtight.The outer circumferential surface of the sleeve 1 is marked with a polarity display using a color hood. Markings 4 such as product name and loft number are made.

[1'-'.

This electronic component is visually inspected before shipping.

Visual inspection includes the plating condition of lead 2 and marking 4.
There are items such as chipping, bleeding, blurring, bending of the lead 2, cracks in the glass sleeve, etc. However, when attempting to automate the inspection of markings among these items, the following problems occurred.

First, since the glass sleeve 1 is transparent and has a cylindrical shape, external light is reflected within the glass sleeve 1, reducing the contrast between the marking area and the adjacent area, especially when the marking is made of white or yellow paint. It was even more difficult to distinguish.

In addition, pattern recognition using a camera does not provide sufficient response due to the fast feeding speed of the diode in the manufacturing process, resulting in a low recognition rate and lack of practicality. The drawback is that it requires parallel installation, resulting in high equipment costs. Furthermore, even if markings are judged to be good or bad by visual inspection, since the glass sleeve is transparent, it is difficult to see the markings and the markings are easily tiring, resulting in erroneous judgments.

- The present invention was proposed in view of the above-mentioned problems.
It is characterized in that it is moved in a direction perpendicular to the axis, irradiates light to a fixed position on the movement trajectory, and detects the light refracted by a member on the movement trajectory to determine whether the marking is good or bad.

Kotane drum An embodiment of the present invention will be described below with reference to FIG.

In the figure, reference numeral 5 denotes a diode (member) shown in FIG. 8, which is marked with a color code by coating the outer peripheral surface of the glass sleeve (transparent cylindrical body) 1 with a certain width of paint at certain intervals. The diode 5 supports the lead 2 on a conveying device such as a chain conveyor (not shown) and moves in a direction perpendicular to the axis. 6 shows the movement locus of the diode 5. 7 is a light source that is placed at a fixed position above the movement trajectory 6 and supplies a long strip of light in the axial direction of the glass sleeve 1; 7a is a lamp; 7b is a parabolic mirror that reflects the light from the lamp 7b and converts it into parallel light; 7c indicates a slit through which a portion of the parallel light rays pass in a band shape. The width of the band-shaped light may be set to be greater than the variation in the support position of the carrier diode and less than the diameter of the diode. 8 is placed at a position below the movement trajectory 6 where it cannot be seen. Further, although not shown, the vicinity of the light source 7 and sensor 8 is designed not to be affected by external light.

This operation will be explained below. As shown in FIG. 2, when the diode 5 crosses the parallel light beam, the light is refracted in the direction of the arrow shown in the figure. Here, light R1 passes through the upper and lower sides of the diode 5.
, R2 proceed in a direction symmetrical to the optical axis plane K passing through the center of the sleeve 1. Therefore, the light beam hitting the lower surface of the sleeve 1 is refracted in a direction away from the sensor 8, and only the light R1 hitting the upper surface side is irradiated onto the sensor 8.

If the width of the light from the light source 7 is made the same as the diameter of the diode 5, the refracted light will be refracted within the range shown in FIG.

Figure 3B shows the diode irradiated with light in this way.
When viewed from the -B side, a shadow area 9 and a light emitting area 10 are obtained as shown in FIG. Therefore, as shown in FIG. 5, a brightness distribution pattern is obtained along the axial direction of the sleeve 1,
An output corresponding to the golden light is obtained from the sensor 8.

Therefore, if the marking 4 is missing, the brightness distribution pattern changes as shown in FIG. 6, and the output of the sensor 8 changes, making it possible to know that the marking is defective.

In addition, since there is no beam 2 in the pellet part, the light transmission area becomes wider, and since the position and orientation of the pellet 3 are also different, the amount of light transmitted increases. The nearby light R3 is blocked from being transmitted by the pellet 3, and even if it were to be transmitted, the transmitted light would not reach the sensor 8 because it is close to the optical axis when it exits the diode 5.

Furthermore, the light ray R4 away from the optical axis K is totally reflected by the inner wall of the glass sleeve 1 and is reflected in the tangential direction thereof, so that it does not reach the sensor 8, so that the light transmitted through the pellet portion does not affect the determination.

Furthermore, due to deformation of the glass sleeve 1 during welding and reflection on the outer surface of the glass sleeve 1, variations occur in the amount of light incident on the sensor 8, which may affect the placement position of the sensor 8 and the judgment level of the output of the sensor 8. You can deal with it by letting it hold up.

Note that the present application is not limited to the above-mentioned embodiments, and includes, for example, not only a diode, but also a member that includes a transparent cylindrical body and marks the outer surface of the cylindrical body. Further, the sensor may be arranged on the same side as the light source with respect to the movement trajectory.

As described above, according to the present invention, since the light refracted by the transparent cylindrical body of the member is detected, the incident light is blocked by the marking at the marking position. Even if the attenuated light enters the transparent cylindrical body, the refracted light is blocked by the marking again at the point where it exits the member, so the contrast between the presence and absence of the marking can be increased.

In addition, since it is only necessary to detect the total amount of refracted light, scanning time is not required compared to pattern recognition using a camera, and pass/fail determination can be made in a short time, and a high recognition rate can be maintained even under high-speed feeding conditions.
Equipment costs can also be kept extremely low.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram showing an example of the present invention, Fig. 2 is a drawing showing the state of refraction of light within the member, Fig. 3 is a drawing showing the arrangement position of the sensor, and Fig. 4 is a drawing showing the state of refracted light. The figure shows a perspective view of the diode, and FIG. 8 shows a partial cross-sectional view of the diode. 1...Transparent cylindrical body, 4...Marking, 6...Movement trajectory, 7...Light source, 8...Sensor. Hisashi 6 figure

Claims (1)

[Claims] A member marked by applying paint to the outer peripheral surface of a transparent cylindrical body is moved in a direction perpendicular to its axis, irradiates light at a fixed position on the movement trajectory, and detects the light refracted by the member on the movement trajectory. A marking inspection method characterized by determining whether the marking is good or bad.