JPH10300436A - Lead frame inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection device capable of automatically detecting whether or not the lead of a lead frame is deformed in the direction of the Z-axis and the degree of the deformation by quantitatively measuring the deformation of the lead of the lead frame in the direction of the Z-axis. SOLUTION: This lead frame inspection device 1 includes a conveying roller 5 for conveying lead frames 3, and measures the thickness of the lead of the lead frame 3 by placing a laser dimension measuring apparatus 7, which emits a laser beam to cast a shadow on the object to be measured to detect the dimensions of the object for measurement from the shadow, in such a way that a laser beam extending the length sufficient for the lead frame 3 conveyed to cross in the direction of its thickness can be applied from the side of the lead frame 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting lead deformation of a lead frame.

[0002]

2. Description of the Related Art In general, a lead frame inspection apparatus for inspecting the deformation of a lead frame is provided with a conveyor or a roller as a transport means for transporting the lead frame, and also has a plane (X) of the transported lead frame. −Y axis) so that the imaging plane is perpendicular to the direction.
A D camera is installed. The CCD camera captures the image of the lead frame being transported as a shadow, and this image is processed through an image processing device connected to the CCD camera to determine whether or not lead deformation has occurred. Areas and the like can be inspected.

[0003]

However, in the lead frame inspection apparatus as described above, since the image captured by the CCD camera is two-dimensional, the plane (X
Although it is effective for the inspection of the deformation in the (−Y axis) direction, there is a drawback that the detection of the lead deformation in the Z axis direction deviating from the plane cannot be dealt with. Moreover, so-called Z-axis deformation of the lead of the lead frame deviating from the XY plane often occurs actually. It has been an issue to provide a function that can automatically detect the degree of deformation.

Further, even if the CCD camera is arranged so that the imaging surface is perpendicular to the side surface of the lead frame to be conveyed, the light emitted from the light source is irregularly reflected in order to make the amount of light incident on the CCD camera uniform. Since it is necessary to keep the shadow, when the lead frame is irradiated, the position of the shadow is likely to shift due to the influence of irregular reflection. That is, CCD
In the image input by the camera, when the X-Y plane of the lead frame is illuminated, the size of the plane is large, so that the error rate of the measurement value due to the displacement of the shadow can be suppressed to a small value. When measuring very small dimensions such as deformation of the frame lead in the Z-axis direction (thickness direction), the ratio of errors in the measured values in the thickness direction becomes extremely large, and the accuracy and reliability of the measured values are high. Lack of sex. For this reason, the detection of minute deformation in the Z-axis direction cannot be dealt with by the lead frame inspection device as described above, and the inspection must be performed by visual inspection using a measuring instrument. However, in the inspection by visual inspection, the operation becomes complicated, and it is difficult to shorten the inspection time, and the operation efficiency is suppressed.

The present invention has been made in view of the above problems, and quantitatively measures the deformation of the lead of the lead frame in the Z-axis direction to determine whether the lead of the lead frame is deformed in the Z-axis direction and whether the lead is deformed. It is an object of the present invention to provide an inspection device capable of automatically detecting the degree of the inspection.

[0006]

In order to achieve the above object, a lead frame inspection apparatus according to the present invention is a lead frame inspection apparatus having a transport device for transporting a lead frame, wherein the lead transported by the transport device is provided. A laser size measuring device is provided so that the thickness of the frame can be measured.

In the present invention, preferably, the laser size measuring device includes means for irradiating a laser beam to form a shadow on the object to be measured, and detecting a size of the object to be measured from the shadow. And a laser beam which is long enough to traverse the conveyed lead frame in the thickness direction so as to be radiated from the side of the lead frame.

That is, the lead frame inspection apparatus of the present invention does not take in an image from a CCD camera and perform image processing as in a conventional inspection apparatus, but the laser emitting section and the laser receiving section of the laser size measuring device are transported. Attach a laser dimension measuring device to straddle the lead frame to be
The thickness of the lead of the lead frame to be inspected can be quantitatively measured. Further, when the measured value is larger than the reference value of the lead thickness of the lead frame using the control device, Is determined to be deformed in the Z-axis direction, and when the measured value exceeds the allowable range, the lead frame can be determined to be defective.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a lead frame inspection apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing a system configuration of an embodiment of a lead frame inspection apparatus according to the present invention, FIG. 2 is a perspective view showing an inspection section in this embodiment, and FIG. 3 is a laser dimension measuring device in this embodiment. FIG. 4 is a cross-sectional view showing the sensor head of FIG. The lead frame inspection device 1 according to the present embodiment includes a transfer unit (not shown) that can transfer the lead frame 3 loaded on the stocker 2a of the loader unit 2 onto the transport roller 5 at regular intervals. The lead frame 3 loaded on the stocker 2a is automatically sent to the transport unit 4 for each sheet. The transport section 4 is provided with a transport roller 5 for transporting the lead frame 3 in the direction of arrow A. A pair of stoppers 6 are provided above the transport roller 5.
The stopper 6 is disposed so that the frontage is gradually narrowed toward the sensor head 8 of the laser size measuring device 7, and the stopper 6 is conveyed so as to pass through the inside of the sensor head 8 of the laser size measuring device 1. Lead frame 3
Can be corrected. Further, the lead frame 3 on the transport roller 5 after passing through the sensor head 8 of the laser dimension measuring device 7 is transferred to the non-defective product stocker 10a or the defective product stocker 10b of the unloader section 10, respectively. There is provided a transfer means (not shown) for obtaining.

[0010] As shown in FIG.
The apparatus includes a sensor head 8 that performs scanning with a laser beam, and a controller 9 that arithmetically controls the operation of the inspection apparatus based on information obtained by the sensor head 8. The sensor head 8 is provided so as to straddle the lead frame 3 transported by the transport roller 5. Sensor head 8
As shown in FIG. 3, a laser emission port 8a for emitting a laser beam as a parallel light beam extending over a length that can be traversed in the thickness direction of the lead frame 3, and a laser emission port 8a having a light receiving element and radiating from the laser emission port 8a A laser beam receiving port 8b for receiving the laser beam is disposed so as to face both sides of the lead frame 3 on the transport roller 5, and a laser beam emitted from the laser emitting port 8a Line scanning is performed in the direction perpendicular to the transport direction (the direction of arrow BB ′), and the laser beam is incident on the laser receiving port 8b.
The laser receiving port 8b is configured to sense a shadow of the lead frame 3 generated when the lead frame 3 passes through the sensor head 8.

The sensor head 8 is connected to the controller 9 via a controller connection cable 9a. In the controller 9, for example, a reference value indicating a lead plate thickness and a reference data indicating an allowable range are stored in advance in a storage area in accordance with a type of a lead frame to be inspected. In the controller 9, an arithmetic processing unit for converting the time detected as a shadow by the sensor of the laser light receiving port 8b as a dimension of the thickness of the lead of the lead frame is incorporated. The thickness of the lead is compared with a reference value of the thickness of the lead previously stored in a storage device, and a comparison process is performed with reference data to detect the presence or absence of deformation of the lead in the Z-axis direction and to use the measured value as a reference allowable range. And a processing device for determining whether the quality of the lead frame is good or not. Further, inside the controller 9, the drive of the roller 5 is controlled so that the lead frame is divided and sent to the defective stocker 10b or the non-defective stocker 10a of the unloader section 10 in accordance with the determination result of the quality of the lead frame. And a processing device adapted to perform the processing. Note that the controller 9 is connected to the unload unit 10 via a cable 9b or the like.

According to the lead frame inspection apparatus of the present embodiment, the laser beam that extends in the thickness direction of the lead frame 3 from the laser emission port 8a is emitted from the side of the lead frame 3 being conveyed. When the lead frame 3 passes through the sensor head 8 of the laser size measuring device 7, the laser beam is line-scanned with respect to the lead frame 3 to be conveyed and is made to enter the laser receiving port 8b. The incident information is sent to the controller 9 as a signal. In this case, the laser light applied to the side surface of the lead frame 3 is
b, the portion is sensed as a shadow at the laser receiving port 8b.

FIG. 4 is a flowchart showing a procedure for inspecting whether or not the lead is deformed in the Z-axis direction by the controller according to the present embodiment. The control device provided inside the controller 9 calculates the time when the shadow is generated in the laser light receiving unit 8b and converts it into the thickness of the lead of the lead frame (step S1). Thus, the thickness of the lead of the lead frame is quantitatively measured. After measuring the lead thickness, a reference plate thickness value of a lead of a lead frame of the same type as the lead frame to be inspected stored in the internal storage area of the controller 9 in advance is obtained (step S).
2) For the lead thickness, the measured value is compared with a predetermined reference plate thickness value (step S3).

If the measured value is larger than the reference plate thickness value, it is determined that the lead is deformed in the Z-axis direction, and the measured value is compared with an allowable range (step S4). If the measured value exceeds the allowable range, the lead frame is determined to be defective and the defective stocker 10 in the unloader section is determined.
b (step S5), if the measured value does not exceed the allowable range, and if the measured value does not exceed the reference plate thickness value, the other lead frames are determined to be non-defective and sent to the non-defective stocker 10a. The transfer means (not shown) is driven as in (Step S6). When determining the lead deformation of the lead frame, the lead deformation may be controlled to be displayed on a display unit (not shown).

According to this embodiment, the thickness of the lead of the lead frame is measured by the shadow of the lead frame generated when the laser beam of the parallel light beam is irradiated within a range that traverses the thickness direction of the lead frame being conveyed. Since the laser beam is irradiated on the lead frame in the state of parallel rays, the shadow sensed at the laser receiving port 8b accurately reflects the outer shape of the lead, and as a result, the thickness measurement accuracy is extremely high. And lead thickness direction (Z-axis direction)
It is possible to measure the amount of deformation in extremely small units.

[0016]

EXAMPLE Using the lead frame inspection apparatus of the present embodiment, the deformation of the lead of a lead frame having a thickness of 0.15 mm in the Z-axis direction was measured. The deformation in the Z-axis direction could be detected.

The lead frame inspection apparatus according to the present invention is not limited to the arrangement of this embodiment as long as the lead thickness of the lead frame can be measured by a laser dimension measuring device. . In addition, the present invention is combined with a conventional CCD lead frame inspection apparatus, and the lead XY plane deformation inspection of the lead frame is performed by CCD image input.
The deformation inspection in the Z-axis direction may be performed by laser scanning using a laser dimension measuring device.

[0018]

According to the apparatus of the present invention, the Z of the lead of the lead frame, which cannot be automatically inspected by a conventional machine, can be obtained.
Automatic inspection of deformation in the axial direction becomes possible, and inspection efficiency and cost can be improved.

[0019]

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a system configuration of a lead frame inspection apparatus according to the present invention.

FIG. 2 is a cross-sectional view illustrating a sensor head of the laser dimension measuring device according to the embodiment.

FIG. 3 is a partial perspective view showing an inspection unit of the lead frame inspection device according to the embodiment.

FIG. 4 is a flowchart showing a procedure for inspecting whether or not a lead is deformed in a Z-axis direction by a controller of the laser dimension measuring device according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead frame inspection apparatus 2 Loader part 2a Loader part stocker 3 Lead frame 4 Transport part 5 Transport roller 6 Stopper 7 Laser dimension measuring device 8 Laser dimension measuring head 8a Laser emission port 8b Laser light receiving port 9 Laser dimension measuring controller 9a Controller Connection cable 10 Unloader section 10a Unloader non-defective product stocker 10b Unloader defective product stocker

Claims (2)

[Claims] 1. A lead frame inspection apparatus provided with a transport device for transporting a lead frame, wherein a laser dimension measuring device is provided so as to measure the thickness of the lead frame transported by the transport device. Lead frame inspection equipment. 2. The laser size measuring device according to claim 1, further comprising: means for irradiating a laser beam to form a shadow on the object to be measured, and detecting a size of the object to be measured from the shadow, and further comprising the means for transporting the object. 2. The lead frame inspection apparatus according to claim 1, wherein the laser beam is provided so as to be able to irradiate the laser beam from the side of the lead frame so as to be able to traverse the lead frame in the thickness direction. 3.