JP2000337837A - Method and apparatus for inspection of lead - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a simple apparatus whose maintenance is made easy and by which an inspection can be performed with high accuracy by a method wherein every lead is passed at a constant speed through an X-shaped sensor in which optical axes of two pairs of photosensors are arranged to be an X-shape and every lead is judged by the output signal of every photosensor. SOLUTION: In this inspection apparatus, the bend of the lead L of an integrated circuit 3 is inspected by an X-shaped sensor 2 composed of two pairs of photosensors P each one pair of which perform a light emitting operation and a light receiving operation and whose optical axes are arranged to be an X-shape. In the apparatus, a rail 5 which passes every lead L through the crossing part 4 of the X-shaped sensor 2 is installed, a constant-speed feed roller 6 which is driven by a pulse motor M in order to transfer the integrated circuit 3 at a constant speed is installed, and slit plates 7 for optical axes are installed respectively on the light transmitting side and the light receiving side of the X-shaped sensor 2. Then, in this inspection method, the lead L which is not bent and which is normal and the lead L which is bent upward or downward are passed through the crossing point 4 at a constant speed, and the quality of the lead L is judged by whether the detection timing of the photosensor No.1 and the photosensor No.2 constituting the X-shaped sensor 2 is deviated or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting lead deformation in an integrated circuit or the like.

[0002]

2. Description of the Related Art At present, with the diversification of various electronic devices, the demand for semiconductor devices tends to further increase. Since these semiconductor elements are automatically mounted on the printed circuit board,
The bending of the lead of the semiconductor element and the attachment of foreign matter have a great effect on the assembling process.

Conventional lead inspection methods and apparatuses use a camera to perform image processing on transmitted light and reflected light from a light source, and compare the data with non-defective lead pitch data to determine the lead pitch direction and lead vertical warpage direction. Inspection for the presence or absence of foreign matter was performed.

[0004]

However, the conventional lead bending inspection requires a large space at the inspection station, and the inspection apparatus itself is complicated. For this reason, there has been a problem that the maintenance is difficult, and it is extremely expensive and cannot be easily introduced.

[0005]

In view of the above problems, the present inventor has accomplished the present invention as a result of intensive studies. An apparatus for inspecting the deformation of a plurality of leads protruding from a component package, wherein an X-shaped sensor having an optical axis arranged in an X-shape by two pairs of photosensors, and each lead passing between the X-shaped sensors at a constant speed. A constant-speed feeder and optical axis slit plates disposed on the light emitting side and the light receiving side of the X-shaped sensor, respectively;

A second aspect of the present invention is an apparatus for inspecting deformation of a plurality of leads protruding from a package of an electronic component,
Two sets of Xs whose optical axes are arranged in two X shapes with four pairs of photo sensors
And a transfer device for passing each lead between the two sets of X-shaped sensors, and optical axis slit plates disposed on the light emitting side and the light receiving side of each X-shaped sensor.

A third aspect of the invention is an apparatus for inspecting the deformation of a plurality of leads protruding from a package of an electronic component,
An X-shaped sensor in which the optical axis is arranged in an X-shape with two pairs of photosensors,
Two pairs of photosensors whose optical axes have the distance between the pitches of the leads, a transfer device for passing each lead between the X-shaped sensors and two pairs of photosensors having the distance between the leads, and a light emitting side of each photosensor And an optical axis slit plate disposed on the light receiving side.

The first invention of the method is a method for inspecting deformation of a plurality of leads protruding from a package of an electronic component, wherein each lead is placed between X-shaped sensors having an optical axis arranged in an X-shape by two pairs of photosensors. Pass at a constant speed and make a judgment based on the output signal of each photo sensor.

A second invention of the method is a method for inspecting the deformation of a plurality of leads protruding from a package of an electronic component, and two sets of X-shaped sensors in which optical axes are arranged in two X-shapes by four pairs of photo sensors. In the meantime, the judgment is made based on the output signal of each photo sensor.

[0010] A third invention of the method is a method for inspecting deformation of a plurality of leads protruding from a package of an electronic component. The method includes the steps of: detecting an optical axis between two pairs of photosensors; Is to allow each lead to pass between two pairs of photosensors having a distance between the pitches of the leads, and to make a determination based on an output signal of each photosensor.

Here, the "photosensor" referred to in this specification
Is to convert and radiate electric quantity into light quantity using light source as medium,
The emitted light is blocked, reflected, absorbed,
The transmitted light undergoes a change, which is photoelectrically converted by a light receiving element.
Some amount of amplification and control is added to the amount of change, and as a control output,
A device that outputs ON-OFF switching. In the present invention, detection of deformation of a lead of an integrated circuit or the like, attachment of a foreign substance, and the like are performed by a light-shielded detection mode. In the present invention, an X-shaped sensor in which the optical axes are arranged in an X-shape with two pairs of photosensors is basically used, and a plurality of leads protruding from the package are provided at a position which simultaneously crosses the two optical axes between the X-shaped sensors. By letting it pass, a determination such as a bend is made.
The X-shaped sensor is one in which the optical axis is arranged in an X-shape so that two pairs of photosensors can simultaneously detect when passing a good non-bending lead. Generally, two optical axes are arranged on the same plane so as to intersect with each other. However, almost the same effect can be obtained even if the two optical axes are arranged at an interval without being in contact with each other. Hereinafter, in this specification, a portion that is detected by two pairs of photosensors simultaneously when a good lead without bending is passed, regardless of whether the two optical axes of the X-shaped sensor are on the same plane or not. It is called an intersection.

When one set of the X-shaped sensors according to the first invention is used, a constant-speed feeder is indispensable. This is because when the lead is bent in the vertical direction, it deviates from the intersection and does not pass through the two optical axes at the same time, so that the detection timing of each photosensor is shifted and the bend can be detected. This is because, when there is, the detection timing of the two pairs of photosensors after passing through the intersection becomes the same, and the detection pitches slightly differ. For this reason, in order to accurately determine the difference between the detection pitches, it is necessary to keep the lead speed at the lead detection position constant and eliminate the variation in the detection in the pitch direction. As a constant-speed feeder, for example, a pulse motor can be used to check the number of pulses and the detection timing of each lead, and compare it with a normal case to perform highly accurate lead bending inspection in the pitch direction. Becomes

In the case of two sets of the X-shaped sensors according to the second invention, it is possible to detect the vertical and pitch bending of the lead without a constant-speed feeder regardless of the lead passing speed and timing. it can. As a general inspection method in this case, the number of leads minus one is determined by arranging two intersections almost at the distance between leads and counting the number of times that four sensors simultaneously detect leads by a counter. Is a method of determining that the product is a non-defective product.

[0014] Even when a pair of X-shaped sensors according to the third invention and a pitch sensor having an optical axis having a distance between lead pitches are combined, there is no constant speed feeder irrespective of the lead passing speed or timing. However, it is possible to detect bending in the vertical and pitch directions of the lead. The inspection method is substantially the same as that of the second invention described above, but the bending in the pitch direction is determined by the output of the pitch sensor, and the case where the number of leads minus one is counted is regarded as a non-defective product. The bending in the vertical direction is the output of the X-shaped sensor, and the case where the number of counts is equal to the number of leads is determined to be a good product. The pitch sensor is
Usually, two pairs of photosensors are provided in parallel with the distance between the leads. However, in the present invention, the optical axis at the place where the leads pass must be at the distance between the pitches. Need not be provided on the same plane.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments of the invention shown in the drawings.

FIG. 1 shows an example of an embodiment of a lead inspection apparatus 1 according to the first invention, in which two pairs of photosensors P for light emission and light reception are arranged so that the optical axis becomes X-shaped. This is an apparatus for inspecting the bent of the lead L of the integrated circuit 3 with the arranged X-shaped sensor 2. In this lead inspection apparatus 1, a rail 5 for passing each lead L of the integrated circuit 3 through an intersection 4 of the X-shaped sensor 2 and a pulse motor M for transferring the integrated circuit 3 at a constant speed are used. Constant feed roller 6
An optical axis slit plate 7 is provided on each of the light emitting side and the light receiving side of the X-shaped sensor 2.

The inspection method using the lead inspection apparatus 1 is as follows.
As shown in FIG. 2, a normal lead L having no bending and a lead L having an upward bending or a downward bending pass through the intersection 4 of the X-shaped sensor 2 at a constant speed, so that the X-shaped sensor 2 is formed. The determination is made based on the detection timing of the sensors NO1 and NO2. The detection timing of each lead L by the X-shaped sensor 2 is shown in FIG. FIG. 7A shows a case of a normal lead L, which passes through the intersection 4 of the X-shaped sensor 2 and is simultaneously detected by the sensors NO1 and NO2 constituting the X-shaped sensor 2. FIGS. 7B and 7C show the case of the upper bent lead L and the lower bent lead L. Since the signal does not pass through the intersection 4, a time lag occurs in the detection of the sensors NO1 and NO2.

When the lead L is bent in the pitch direction, the lead L passes through the intersection 4 of the X-shaped sensor 2 at a constant speed as shown in FIG. 4A and is simultaneously detected as shown in FIG. But
Variations occur in the detection intervals. Therefore, these detection results can be compared with the detection result of the normal lead L to determine whether there is a vertical bend or a pitch bend.

FIG. 5 shows a lead inspection apparatus 21 according to the second invention.
This is a structure in which two sets of X-shaped sensors 2 are provided, and each intersection 4 is arranged at a distance between the pitches of the leads L. Substantial inspection can be performed without providing an apparatus. In this example, the inclined rail 8 is provided as a transfer device for the integrated circuit 3, but the transfer may be performed by using an air cylinder or the like.

The inspection method by this lead inspection device 21 is based on the sensor NO1, the sensor
The detection data of NO2, sensor NO3, and sensor NO4 are input to an AND circuit, and outputs are counted by a counter to judge pass / fail. This satisfies the number of leads L minus the count number of 1 only when the lead L is normal as shown in FIGS. 6A, 6B, and 6C.
Other cases are determined as defective.

As another example of the second embodiment of the method, as shown in FIG. 7, a non-defective sample is passed through the apparatus of the present invention, and the read passage time data at this time is registered in the reference passage speed memory. Then, the shift time data between the four photosensors P when the read is detected at the same time is stored in the reference timing memory. The above-described reference sample storage operation is to simultaneously calibrate the error of the mounting position of each sensor constituting the two sets of X-shaped sensors 2 and the error of each slit position of the optical axis slit plate 7. In the lead inspection performed thereafter, first, the difference between the passage speed of the inspected lead and the reference passage speed is calculated. Then, the shift time data between the four photosensors P at the time of the inspection is corrected using the calculated difference data. Next, the difference between the reference timing data and the corrected timing data between the photosensors is obtained, and the difference is compared with preset pass / fail judgment tolerance data.

FIG. 8 shows a lead inspection apparatus 31 according to the third invention.
1 shows an example of the embodiment, in which one set of X-shaped sensors 2
And a pitch sensor 9 having two pairs of photosensors P whose optical axes are arranged at the distance between the pitches of the leads L. This inspection device 31 can also perform a substantial inspection without providing a constant-speed feeding device such as the constant-speed feeding roller 6.

In the inspection method by the lead inspection device 31, the bending in the pitch direction is detected by the pitch sensor 9, and the bending in the vertical direction is detected by the X-shaped sensor 2. First, in the pitch direction, as shown in FIGS.
The detection data of the non-defective product and the non-defective product by the sensor 1 and the sensor NO2 are different from each other. For the vertical direction, see FIG.
(A) Sensor NO constituting X-shaped sensor 2 as in (b)
If the same number as the number of leads L passing through 3 and the sensor NO4 is counted, it can be determined as a non-defective product.

As another example of the third embodiment of the method, the inspection can be performed in the same manner as the inspection method based on the comparison between the calculated value and the pass / fail judgment tolerance data described in the second invention of the method (FIG. 7). it can.

In the first invention, the second invention and the third invention, as a method of calibrating the output timing by each photosensor P, usually, the mounting position of each photosensor P is adjusted or the slit position of the slit plate 7 for the optical axis is adjusted. Perform by adjustment. In addition, assuming that a constant-speed feeder is provided, FIG.
As shown in FIG. 1 (a), read detection timing adjustment volumes VR1, VR2, VR3 for the input of each photo sensor P.
, VR4 may be provided respectively. This is shown in FIG.
Among the sensors P, the read detection timing adjustment volume VR1 is assigned to the sensor P with the latest detection timing.
, VR2, VR3, and VR4.

In this embodiment, a lead bending allowable value setting volume VR for setting the allowable level of the lead L is provided.
5, VR6, VR7, VR8. In this case, the detection accuracy can be arbitrarily set by adjusting the pulse width t in FIG. 4B with each lead bending allowable value setting volume.

[0027]

As described above, in the lead inspection method and apparatus according to the present invention, one or two sets of X-shaped sensors, or one set of X-shaped sensors and one set of pitch sensors are provided, and electronic components are provided on these sets. By passing a lead protruding from the package and performing the bending inspection of the lead, extremely accurate inspection can be performed. Further, since the structure is extremely simple, the maintenance and management of the apparatus is easy, and the apparatus can be introduced at low cost, which has extremely useful effects in practical use.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a lead inspection device according to a first invention.

FIG. 2 is a schematic front view showing an example of a lead passing state in the lead inspection device according to the first invention.

3 (a), (b) and (c) are output diagrams of each sensor when passing through the lead shown in FIG. 2, respectively.

FIG. 4A is a schematic front view showing another example of a lead passing state in the lead inspection apparatus according to the first invention, and FIG.
FIG. 6A is an output diagram of each sensor when passing the lead shown in FIG.

FIG. 5 is a perspective view showing an example of an embodiment of a lead inspection device according to the second invention.

FIGS. 6 (a), (b) and (c) are output diagrams of each sensor when the lead passes through the lead inspection apparatus according to the second invention.

FIG. 7 is a block diagram showing another example of the embodiment of the lead inspection method according to the first invention and the second invention.

FIG. 8 is a perspective view showing an example of an embodiment of a lead inspection device according to the third invention.

FIGS. 9A and 9B are output diagrams of a pitch sensor when the lead passes through the lead inspection apparatus according to the third invention.

FIGS. 10A and 10B are output diagrams of an X-shaped sensor when a lead passes through the lead of the lead inspection device according to the third invention, respectively.

11A is a block diagram showing another example of the embodiment of the lead inspection apparatus according to each invention, and FIG. 11B is an output diagram showing an adjustment state according to FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lead inspection device according to first invention 21 lead inspection device according to second invention 31 lead inspection device according to third invention 2 X-shaped sensor 3 integrated circuit 4 intersection 5 rail 6 constant-speed feed roller 7 slit plate for optical axis 8 Inclined rail 9 Pitch sensor P Photo sensor L Lead M Pulse motor

Claims (7)

[Claims] An apparatus for inspecting the deformation of a plurality of leads protruding from a package of an electronic component, comprising: an X-shaped sensor in which an optical axis is arranged in an X-shape by two pairs of photosensors; and each lead between the X-shaped sensors. A lead inspection device, comprising a constant-speed feeding device that allows the X-shaped sensor to pass through at a constant speed, and optical axis slit plates disposed on the light emitting side and the light receiving side of the X-shaped sensor, respectively. 2. An apparatus for inspecting the deformation of a plurality of leads protruding from a package of an electronic component, comprising: two pairs of X-shaped sensors having optical axes arranged in two X-shapes by four pairs of photosensors;
A lead inspection apparatus comprising: a transfer device for passing each lead between a pair of said X-shaped sensors; and optical axis slit plates disposed on a light-emitting side and a light-receiving side of each X-shaped sensor. 3. An apparatus for inspecting deformation of a plurality of leads protruding from a package of an electronic component, wherein an X-shaped sensor having an optical axis arranged in an X-shape by two pairs of photosensors and an optical axis by two pairs of photosensors are provided. A pitch sensor arranged at a distance between the leads, a transfer device for passing each lead between the X-shaped sensors and between the pitch sensors, and a slit plate for an optical axis arranged on a light emitting side and a light receiving side of each photo sensor, respectively. And a lead inspection device. 4. A method for inspecting deformation of a plurality of leads protruding from a package of an electronic component, wherein each lead is passed at a constant speed between X-shaped sensors having an optical axis arranged in an X-shape by two pairs of photosensors. A lead inspection method, wherein the determination is made based on an output signal of each photosensor. 5. A method for inspecting deformation of a plurality of leads protruding from a package of an electronic component, wherein each lead is placed between two sets of X-shaped sensors in which optical axes are arranged in two X-shapes by four pairs of photosensors. A lead inspection method characterized in that the signal is passed through and determined based on the output signal of each photo sensor. 6. A method for inspecting the deformation of a plurality of leads protruding from a package of an electronic component, the method comprising: an X-axis sensor having an optical axis arranged in an X-shape by two pairs of photosensors; A lead inspection method characterized in that each lead is passed between pitch sensors arranged at a distance between pitches of the lead, and determination is made based on an output signal of each photo sensor. 7. The lead passing time data of a good sample is stored in a reference passing speed memory, and the reference timing data of the lead detection by each photosensor is stored in a reference timing memory. The correction is made by a difference between the passing speed and the passing speed of the inspected lead, and the calculated value of the difference between the corrected timing data and the reference timing data is compared with the set pass / fail judgment tolerance data to make a determination. 6. The lead inspection method according to 6.