JPS6042885B2 - IC lead bending inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an apparatus for inspecting the bending of IC leads, and more specifically, the present invention mainly focuses on checking whether the tips of the external leads of DIP plastic molded ICs are within a bending range that allows automatic insertion into a printed board, etc. It relates to a device for inspecting whether or not the

Conventionally, the limit gage method for testing the bending of external leads of ICs has been considered, in which a mechanical gauge is passed through the gap between each lead to inspect the bending of the leads, but the test takes a long time because it processes each ICI. Alternatively, for reasons such as the need to accurately determine the position of the IC, visual inspection was often performed by the operator.

In recent years, advances in automation and labor-saving technology in the IC manufacturing process have been remarkable, and while the diffusion process and assembly process are becoming unmanned factories, only the final process, the IC lead bend inspection before shipping, is a visual inspection that relies on human hands. The company is conducting inspections, which has become a bottleneck in fully automating the entire line.

SUMMARY OF THE INVENTION An object of the present invention is to provide an IC lead bending inspection device that can quickly inspect the position of the tip of an ICIJ lead.

In order to achieve the above object, an IC lead bending inspection device according to the present invention holds an ICI piece and places an IC lead on a translucent glass plate surface.
A contact mechanism that lightly presses the lead tip; an imaging device that scans and captures an image of the lead tip through a translucent glass plate; an amplification circuit that amplifies the image pickup tube output; A binarization circuit that converts into a value, a storage circuit that stores reference IC lead tip position information, and a storage circuit that extracts each lead tip position from the binarized signal of the lead tip image, and further extracts the reference IC lead tip position information of the storage circuit. It is comprised of a determination circuit that compares and calculates lead tip position information to determine pass/fail, and a control circuit that sends a synchronization signal to the imaging/imaging device and a drive signal to the contact mechanism.

According to the configuration of the present invention, only the unbent lead tip image is projected on the surface of the semi-transparent glass plate, and by reading this image with an image pickup tube and comparing it with the standard IC lead pitch, the bending of all the leads is calculated. You can check.

Furthermore, the amount of information to be processed is relatively small, allowing for rapid processing. The present invention will be explained in more detail below with reference to the drawings.

Figure 1 is a diagram showing the bending state of the IC lead to be inspected, where a shows the bending in the direction perpendicular to a line of leads when looking at the IC from the side, and b shows the bending in the same direction with respect to the line of leads. It is a figure showing how to bend.

The bending forms of the IC lead are A, b, al: d. (b) has a compound shape, and in more extreme cases, it is completely crushed or cut and the lead is missing. The general allowable range for the bending of these IC leads varies depending on the hole diameter of the printed board used, but for automatic feeding and insertion using an insertion machine, etc., the bending range is approximately 0.2 to 0.3 wm for the specified dimensions. It is said that the degree of Figure 2 is I
This shows the image of the lead 2 formed on the semi-transparent glass plate 4 when Cl is pushed up parallel to the semi-transparent glass plate 4 and the tip of the lead 2 comes into contact with it. An image of only the tip is faithfully formed, but if the tip is curved inward or outward with respect to the specified pitch P2, it is captured as a rather small point such as 3''.

Similarly, leads that are bent or twisted relative to the specified pitch P1 will be imaged at the tip of each lead as a slightly smaller dot as shown in 3''.Furthermore, extremely curved leads will form an image on a translucent glass plate. No image.By using this translucent glass plate 4, it is possible to read only the necessary information, and information such as unnecessary images other than the lead tip and noise etc. is extremely reduced.Figure 3 shows the present invention. 2 is a block diagram showing the configuration of an apparatus according to ICl. The tip of the lead 2 is lightly pressed against the surface of the translucent glass plate 4 by the contact mechanism 10 in response to a signal from the control circuit 17.
On the opposite side, only the portion where the tip of the lead 2 is in contact is clearly shown. This image is captured by an imaging device 11 such as IT■. Appropriate lighting means 1 as required
2, a clearer image can be obtained. The signal sent out in series from the imaging device 11 is amplified by the amplifier circuit 13 and further binarized by the binarization circuit 14 into ゜゜1゛ or ``0'' at an appropriate level. The standard dimensions of the IClJ-de and the tolerance range of dimensional errors are stored.The determination circuit 16 extracts the tip position of the IC lead 2 from the binarized signal and compares it with the standard dimension in the storage circuit 15. A pass/fail judgment is made for all of the leads 2. Since the device according to the present invention is configured as described above, the image of the tip of the IC lead formed on the semi-transparent glass plate is read by the imaging device and compared with the standard dimensions. By performing calculations, it is possible to quickly determine whether the object to be inspected is good or bad, and is ideal for inspecting bent legs of mass-produced products such as ICs.

[Brief explanation of drawings]

Figure 1 is a diagram to explain the bent state of the leads of the IC to be inspected, and Figure 2 is the IC imaged on a semi-transparent glass plate.
FIG. 3 is a block diagram showing an embodiment of the present invention. 1...ICl2...Read, 3...
...Projected image of lead tip, 4...Translucent glass plate, 10...Contact mechanism, 11...Imaging device, 12...Illumination means , 13...
Amplification circuit, 14... Signal binarization circuit, 15...
・Memory circuit, 16... Judgment circuit, 17...
・Control circuit.

Claims (1)

[Claims] 1. A contact mechanism that holds the IC and lightly presses the IC lead tip against a translucent glass plate, an imaging device that scans and captures an image of the lead tip through the semitransparent glass plate, and an amplification device that amplifies the output of the imaging device. circuit, a binarization circuit that binarizes the amplified signal with an appropriate threshold, a storage circuit that stores reference IC lead tip information, and a binarized signal of the lead tip image. A determination circuit extracts the position of the lead tip of the lead and further compares it with the reference lead position information to determine pass/fail, and a control circuit sends a synchronization signal to the imaging device and an operation signal to the contact mechanism. An IC lead bending inspection device characterized by: