JPH032608A - Lead inspection method, lead measurement device and lead inspection device used therefor - Google Patents

Abstract

PURPOSE:To make it possible to measure the position relation automatically without human working by facing an electronic device having a package with a mirror surface, sensing the real images and the virtual images of the lead group, and processing the image signals. CONSTITUTION:A QFP IC 1 having a quad flat package is made to face a mirror surface 90 in parallel. Light is projected from a lighting device 100. The real images and the virtual images of a lead group are picked up with TV cameras 93 in a plurality of directions. An image processing part 96 measures the central position, the position of the tip of the real image and the position of the tip of the virtual image for each lead 3 based on the image signals. Furthermore, the pitch of the leads, the interval between the tip of the real image and the tip of the virtual image and the differences between the tip positions of the real image and the virtual images and a reference position are obtained for each lead 3. In a judging part 98, the quality of each lead is automatically judged from the data for three directions of X, Y and Z.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a lead measurement and inspection technique, and in particular to a technique for measuring and inspecting the position of a group of leads in an electronic device equipped with a surface-mounted package. A semiconductor equipped with! ! The present invention relates to an item that is effective for use in screening and inspecting the appearance of leads in No. 41 circuit devices (hereinafter sometimes referred to as ICs) to determine whether they are good or bad. [Conventional technology] Recently,

[C (hereinafter sometimes abbreviated as surface mount IC) is becoming smaller, thinner, and lighter, and is equipped with a surface mount package to meet the demands for high-density mounting. ) is rapidly becoming popular. The surface mount type 1G, combined with the mounting of chip components, is promoting automation of board mounting. However, even with automatic chip component mounting equipment, a 100% placement accuracy rate cannot be expected, and as the number of components per board increases, the cumulative defective placement rate also increases, and when evaluating one board as a unit. , we are now counting single- to double-digit percentage defects. In order to quickly discover and eliminate such defective boards during the manufacturing process, there is a need for the development of an automatic mounting device for mounting. On the other hand, on the supply side of surface-mounted ICs, in order to prevent the occurrence of mounting defects after mounting on a board, an external appearance inspection of the leads is performed before shipping the product. However, there are no measurement standards specified for the inspection items for the leads of surface mount type 1c, and the positional relationship between the leads in the lead group row on each side of the package alone cannot unambiguously determine the state at the time of mounting. Since it is difficult to specify the conditions, visual inspection of the leads of surface mount ICs is currently performed manually. Incidentally, an example that describes the chip component mounting inspection technique is P63-P69 of Kogyo Chozai, November 10, 1987, published by Kogyo Chosenkai Co., Ltd., November 10, 1987. Another example of a lead inspection technique is IL Japanese Patent Application No. 63-164726. [Problem to be solved by the invention] Relying on manual labor to inspect the appearance of leads of surface-mounted ICs not only limits productivity, but also
There are also limits to the credibility of testing. Therefore, there is a need to develop a lead inspection device that can automatically perform a visual inspection of the leads of surface-mounted ICs. The issues that need to be solved in the development of this lead inspection device are:
Measure the mutual positional relationship of the leads in that state, judge whether the appearance of each lead is good or bad in relation to the entire lead group, ensure that the lead is not deformed by the measurement, and stably image the lead that is the subject of inspection. The LC can be automatically sent to the inspection stage. A first object of the present invention is to provide a lead measurement technique that can automatically measure the positional relationship of a group of leads in an electronic device equipped with a surface-mounted package, assuming the state when surface-mounted. There is a particular thing. A second object of the present invention is to provide a lead inspection technique that can automatically determine whether the appearance of an IJ is good or bad based on the measurement. A third object of the present invention is to provide a lead inspection technique that can automatically set an electronic device as an object to be inspected and stably capture images of a group of its leads. The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings. [Means for Solving the Problems] Representative inventions disclosed in this application will be summarized as follows. That is, this is a lead inspection method for inspecting the positional relationship of a group of leads in an electronic device equipped with a surface mount package, in which the electronic device is faced parallel to a mirror surface, and a real image of the group of leads of the electronic device is inspected. , by making the virtual images reflected on the mirror surface face each other? j [Images are taken from several directions, the real image and the virtual image of the lead are compared based on the image signals of the real image and the virtual image, and the center position, real image tip position, and virtual image tip position are determined for each lead. Then, based on this measurement data, the pitch, the distance between the real image tip position and the virtual image tip position, and
The difference between at least the real image or virtual image tip position and the reference position is determined, and the positional relationships of each lead in the circumferential direction, vertical direction, and radial direction are inspected. [Operation] According to the above-mentioned means, the X of the lead can be adjusted with only one direction image.
It is possible to simultaneously measure the positional relationships in three directions: (circumferential direction), Y (radial direction), and Z (vertical direction). As a result, based on the measurement data, the xSy of the lead is
It is possible to automatically check whether the positional relationship of Sz is good or bad in three directions. Since the electronic device to be inspected is inspected parallel to the mirror surface, the inspection condition corresponds to the state when the electronic device with the surface mount package is mounted. This means that the positional relationship of the leads of the device is automatically inspected before mounting, assuming the state at the time of mounting. [Example] Figure 1 shows lead inspection values that are an example of the present invention! 2 and 3 are explanatory diagrams for explaining its function, and 4 and 5 are schematic diagrams showing Q as an object to be inspected.
A perspective view and a partially cutaway front view showing the mounting state of the FP/IC, FIG. 6 is an external perspective view showing the entire lead inspection device,
FIG. 7 is a plan view thereof, and FIGS. 8 and subsequent figures are explanatory views showing each component thereof. In this embodiment, the lead inspection device used in the lead inspection method according to the present invention is an IC (hereinafter referred to as QFP-IC) equipped with a quaternary flat package, which is an example of an IC equipped with a surface mount package. , or an object to be inspected or a workpiece.) It is configured to be able to implement the visual inspection of a group of leads in (2). The QFP/tCt as an object to be inspected or a workpiece is equipped with a resin-sealed package 2 made of resin into a substantially square flat shape, and the four sides of this package 2 are gull-wing shaped. A plurality of bent portions 3 are arranged horizontally in a row with their lower ends aligned, and protrude toward one end surface (hereinafter referred to as the lower surface side). Then, this QFP/ICI is mounted on a printed wiring board as shown in FIGS. 4 and 5. 4 and 5, a printed wiring board 4 has a plurality of lands 5, and a resin-sealed QFP to be mounted.
- It is arranged so as to correspond to each lead 3 in the ICI, and is formed into a substantially rectangular thin plate shape using a solder material, and the three groups of leads of this ICI are aligned and abutted on the five groups of lands, respectively. At the same time, each lead 3 and land 5 are electrically and mechanically connected by a solder layer 6 formed by reflow soldering. Therefore, in the state assumed at the time of implementation, QFP-I
C1 will be inspected for the following items regarding the positional relationship of its lead group. (1) Circumferential spacing (pitch) between adjacent leads
. (2) Height of the bottom end surface of the lead relative to the reference surface (mounting surface) (lifting of the bottom end surface of the lead from the land). (3) Position of the lead in the package radial direction (bending of the lead in the inward and outward directions). In this embodiment, the lead inspection device fIO according to the present invention
is equipped with a machine base 11, and as shown in FIGS. 6 and 7, a pair of rail 1
2 are laid in the front-back direction. As shown in FIG. 8, a loading device 13 is installed on the rail 12J to move in the front and back direction, and the loading device 13 has a plurality of uninspected product trays 14 storing uninspected products. They are piled up and stocked. The loading device 13 is equipped with an elevator 15, and the elevator device 15 is configured to be able to raise the stacked uninspected trays 14 one pitch at a time. As shown in FIG. 8, an empty tray temporary storage stand 1 is located on the right side of the loading device rail 12 on the machine stand 11.
6 is installed parallel to the rail 12, and this temporary stand 1
6, an empty tray [7] from which all uninspected items have been removed by the loading device 13 is transferred. Furthermore, a pair of unloading device rails 18 are laid on the right side of the temporary stand 16 on the machine stand 11, parallel to the loading device rails 12, and on the rails 18, an unloading device 19 is moved in the front and back direction. It is equipped to do so. The unloading device 19 has a storage section 21 for storing good product trays 20 containing inspected non-defective products, and an empty tray 17 into which non-defective products will be stored is positioned at the upper end of the storage section 21. A pair of left and right tray positioning claws 22 are provided to move in and out of the storage section 21 in the radial direction. The unloading device 19 is equipped with an elevator 23.
3 picks up the good tray 20 on the tray positioning claw 22 and lowers it to the ■ pitch, so that a plurality of good trays 20 are stored in the storage section 21 in a stacked state. In addition, a defective product tray stand 24 is installed in parallel with the rail 18 on the right side of the unloading device rail 18 on the machine stand 11, and this tray place 24 is used to store defective products that have been inspected. One non-defective tray 25 is placed. A Y-table 31 is placed on the left end of the machine base 11 in the front-rear direction, and a Y-direction slider 32 is mounted on the Y-table 31 so as to be slidable in the front-rear direction. The slider 32 is configured to be moved under control B by suitable means (not shown) such as a feed screw mechanism or the like. On the other hand, there is a rail 3 on the right end of the machine base 11.
3 are laid in the front-rear direction, and a Y-direction slider 34 is mounted on this rail 33 so as to be slidable in the front-rear direction. There is an X table 35 between the left and right Y direction sliders 32 and 34.
is arranged perpendicularly to the Y table 31 and the rail 33 and is bridged, and the X table 35 has a first x-direction slider 36 and a second x-direction slider 37 mounted so as to move in the left-right direction, respectively. The X-table 35 and both sliders 36 and 37 are configured as linear pulse motors (not shown), and both sliders 36 and 37
are each moved in the left and right direction with precise control. As shown in FIGS. 9 and 10, a base 4o is fixedly mounted on the first X-direction slider 36, and a tray handling device 4 is mounted on the front center of the base 40.
1 is installed. That is, this handling family W
41 is provided with a guide rail 42, and the guide 42 is integrally laid on the front lower surface of the base 4o in the vertical direction. A vertical slider 43 is mounted on the guide 42 so as to be slidable in the vertical direction, and a U-shaped bracket 44 is fixed to the slider 43 so as to protrude forward. A cylinder device 4 is provided on the front upper surface of the base 40.
5 is installed vertically downward, and the upper end of the bracket 44 is fixedly connected to the piston rod 46 of the cylinder device 1145. A tray vacuum suction head 47 is installed vertically downward at the lower end of this bracket 44.
7 is configured to attract and hold the tray by being supplied with negative pressure via the negative pressure supply path 48. This head 47 is moved up and down by a cylinder device 45 via a bracket 44. A first workpiece handling device 50 is installed on the rear left side of the base 40 . That is, a first guide rail 51 is vertically arranged and fixedly laid in the center left side of the rear end of the base 40.
A vertical slider 52 is mounted to be slidable in the vertical direction. A first hand 53 for a workpiece formed in an L-shape is fixed to the vertical slider 52 with its horizontal member facing downward, and a first vacuum suction for a workpiece is attached to the tip of the horizontal member of the hand 53. head (hereinafter referred to as the first suction head)
) 54 is installed vertically downward, and this first suction head 54 is supplied with negative pressure through a negative pressure supply path 55 to suction the QFP/ICI as a workpiece into its resin-sealed package 2. is configured to hold the Further, on the rear side of the base 40, a bracket 56 is arranged on the left side of the first guide rail 51 and fixedly protrudes, and a cylinder device 57 for the first suction head is arranged vertically upward on the bracket 56. It has been installed. The piston rod 58 of this cylinder device 57 has a first
Hands 53 are connected via a connecting member 59. Therefore, the second suction rod 54 is moved up and down by the cylinder device 57 via the connecting member 59. Further, a second workpiece handling device 60 is installed on the rear right side of the base 40, and this handling device 60 is configured to be symmetrical with the first workpiece handling device 50 on the left side. That is, a second guide rail 61 is vertically arranged and fixedly laid in the left center part of the rear end of the base 40, and a vertical slider 62 is installed on the second guide rail 61.
is mounted so that it can slide vertically. A second hand 63 for workpieces formed in an L-shape is fixed to the vertical slider 62 with its horizontal member facing downward, and a second vacuum suction for workpieces is attached to the tip of the horizontal member of this hand 63. A head (hereinafter referred to as a second suction head) 64 is installed vertically downward, and this second suction head 64
is configured to attract and hold the resin-sealed package 2 of the QFP-1c as a workpiece by being supplied with negative pressure through the negative pressure supply path 65. Further, on the rear side of the base 40, a bracket 66 is disposed on the right side of the second guide rail 61 and fixedly protrudes, and the bracket 66 has a cylinder device 67 for rad for the second suction so as to be vertically upward. arranged and installed. A second hand 63 is connected to the piston rod 8 of the cylinder device 67 via a connecting member 69. Therefore, the first suction head 64 is connected to the connecting member 6 by the cylinder device 67.
It is designed to be moved up and down via 9. As shown in FIGS. 6 and 7, the second X-direction slider 37 is equipped with a third workpiece handling device 71.
and a fourth workpiece handling device 72 are arranged symmetrically on the rear side, and both handling devices 7L and 72 are configured similarly to the first and second handling devices 5o and 60. , the explanation of its configuration will be omitted. As shown in FIGS. 6 and 7, a lead correction device t73 is installed on the rear left side of the machine stand 11. As shown in FIG. 11, this lead correction device 73 includes an upper mounting plate 74 and a lower mounting plate 75.
7 has been added to each. A vacuum suction head 77 is slidably inserted into the lower mold 77, and by moving the head 77 up and down, it picks up the QFP as a workpiece.
- The receiver is configured to pass the ICI to the lower die 77. Positioning claws 7 formed in a V claw shape are provided on both sides of the lower die 77.
9 are installed symmetrically, and the positioning claws 79 engage from both directions with the corners of the resin-sealed package 2 of QFP-ICI as a workpiece inserted on the lower die 77, thereby forming the QFP-1c. ] is configured to position the upper die 76 and the lower die 77. As shown in FIGS. 6 and 7, a first inspection execution section 80 for executing a lead inspection is installed in the center of the rear path on the machine base 11. In the execution section 80, a centering/resetting station 81 and a measuring station 82 are set at front and rear positions. That is, as shown in FIG. 12, a feed screw shaft 83 is arranged on the machine base 11 in the front-rear direction and rotatably supported, and this feed screw shaft 83 is connected to a pulse motor 84.
It is designed to be driven to rotate in forward and reverse directions. A table 85 is movably screwed and mounted on the feed screw shaft 83, and the table 85 is moved back and forth between the stations 81 and 82 by forward and reverse rotation of the feed screw shaft 83. It is composed of In this embodiment, as shown in FIG. 12, a rod 86 is arranged along the center spring and is slidably penetrated through the table 85, and the rod 86 is connected to a cylinder device. It is configured to be moved up and down by a drive device 87 consisting of, etc. A suction chuck 88 connected to a negative pressure supply path 89 is formed on the upper surface of the rod 8G, and the suction chuck 88 is QF by the vacuum suction force.
By suctioning the lower surface of the P-ICI package 2, the QFP-IcI as a workpiece can be positioned and held. The top surface of this table 85 has a mirror surface 9.
0 is positioned and held above the table 85.
It is formed to project the JCI as a whole from the bottom. The mirror surface 90 may be formed by placing the mirror itself on the table 85, or by polishing the surface of the table 85 itself, or by polishing the surface of the table 85 itself. It may be formed by applying a film or the like, and the means of forming it is not limited, but it is desirable to form it so that it is as free from distortion as possible and has wear resistance. As shown in FIGS. 6, 7, 13, and 4, the measurement station 82 of the first test execution section 80
has a pair of left and right image capture devices 9LA and 9113.
However, since the six image capture devices 9LA and 91B installed on the left and right sides of the feed screw shaft 83 have the same structure and are symmetrically constructed, one of them will be explained using the same reference numerals. do. The image capture device 91A (and 91B) includes a lens barrel 92, which is vertically erected on one side of the feed shaft 83. At the bottom 2 of the tli1 cylinder 92, there is a television camera (hereinafter referred to as a camera) 9 for lead measurement, which serves as an imaging device that captures real images and virtual images of the lead group.
3 is arranged vertically upward, and this camera 93 is installed so that the lead 3 of the QFP-1cL as the object to be inspected is held on the mirror surface 90 of the table 85, as shown in the monitor image to be described later. It is set so that a real image of the lead group and a virtual image of the lead group reflected on the mirror surface 90 can be simultaneously projected. Further, an optical system such as a lens 94 and a plurality of reflecting mirrors 95 is incorporated in the lens barrel 92, and these optical systems enable the camera 93 to simultaneously capture a real image and a virtual image of the lead group. . The camera 93 includes an image processing device 96 which together with the camera 93 substantially constitutes at least a part of the lead measuring device.
is connected to the image processing device 96, and the image processing device 96 is configured to send an image signal to a monitor 97 connected to one of its output terminals to monitor a desired image. It is configured to transmit a predetermined measurement signal to the determination section 98 connected to the other output terminal of. A setting section 99 is connected to this determination section 98 for setting determination reference values regarding lead arrangement as will be described later. By calculating the difference from the setting value sent from the setting unit 99 and comparing whether the difference is within the tolerance range, it is determined whether the actual measured value is outside the tolerance range from the reference value. In this case, the lead arrangement is determined to be defective, and the determination result is transmitted to an external device (not shown). Further, as shown in FIGS. 1, 13, and 14, the table 85 is equipped with a lighting device 100, and this lighting device is used to illuminate the object to be inspected held on the table 85. It is configured to uniformly illuminate three groups of leads on the left and right sides of the QFP/ICI. That is, the lighting device 100 includes a dark box 101,
The dark box 10 is constructed on the table B5. Inside the dark box 101, a circular ring-shaped light source 102 is arranged and supported parallel to and concentrically with the table 85, and the light source 102 illuminates the inside of the dark box 101 as uniformly as possible. It is composed of Further, a plurality of upper reflectors 103 are attached to the ceiling wall of the dark box 101 so as to reflect the illumination light from the light source 102 downward, and a plurality of horizontal Jt boards 104 are attached to the side wall of the dark box Lot. light source 1
It is attached so that the illumination light from 02 is reflected laterally toward the third group of leads. In addition, dark box 10
A shielding plate 105 is erected at each of the four corners of 1 so as to shield the adjacent spaces, and the shielding plates Ui 105 prevent illumination light and shadows in the adjacent spaces from interfering with each other. As shown in FIGS. 6 and 7, a second inspection execution section 110 is installed at the rear right end of the machine 1, and the second inspection execution section 110 has a setting section and a A resetting station 111 and a measuring station 112 are set to the left and right positions. The configuration of the second inspection execution section J'0 is different from the first inspection execution section 80 in that it is configured symmetrically in the front and back, whereas the first inspection execution section 80 is configured symmetrically in the left and right directions. Detailed explanation will be omitted. That is, the second inspection execution unit 10 includes an image capture device 113A and an IL 3B, an illumination device 114, etc. installed on both sides of the measurement station 112. Next, an embodiment of the lead inspection method according to the present invention will be described using the lead inspection apparatus having the above configuration. In advance, as shown in FIG. 8, a plurality of uninspected product trays 14 containing a plurality of QFP-ICIs as workpieces to be inspected are stacked on the loading device 13 and stonked. . In addition, empty trays are set in the storage section 21 and defective tray stand 24 of the unloading device 19 as non-defective trays 20 and defective trays 25, respectively. When the lead inspection starts, first, the loading device 1
QFP-IC as a workpiece from the uninspected tray 14 of 3
I is held by vacuum suction by the first handling device 5o and pinked up. The first handling device 50 is
1st X by control of table 35 and Y table 31
By being moved by operating the direction slider 36, the pinked-up track 1 is transferred to the lead correction device 73. In the lead correction device 73 shown in FIG.
First, the corrected workpiece is transferred from above the lower die 77 to the second handling device 60 by the vacuum suction spatula L7B of the lead correction device 73. When the vacuum suction head 78 becomes vacant, the first slider 36 is moved slightly to the right, and the first handling device 5
Work 1 of 0 is transferred to the door 8 for vacuum suction. The workpiece J is lowered by the vacuum suction head 78 and positioned relative to the lower mold 77 by the positioning claw 79 . vt, the upper die 76 and the lower die 77 are clamped, whereby the lead 3 of the workpiece 1 is corrected. After being corrected by clamping the upper mold 76 and lower mold 77 of the lead correction device 73, the receiver is transferred to the second handling device 60 by vacuum suction from above the lower mold 77 by the rad 78. The workpiece L that has been supported is transferred to the setting/resetting station 81 of the first inspection execution section 80 by operating the first X-direction slider 36. At the setting/re-centering station 81 shown in FIG. 12, the suction chuck 88 is first raised relative to the table 85 by the rod 8G. Subsequently, when the second handling device 60 transfers and positions the QFP-ICI as the object to be inspected onto the suction chuck 88 with the lead 3 facing downward, the suction chuck 88 receives air from the negative pressure supply path 89. Negative pressure is supplied and QFP・
The ICI is positioned and held above the mirror surface 90 of the table 85. kjt, the rod 8 is moved by the drive device 87.
6 is lowered by a predetermined stroke, and the QFP/ICI held by the suction chuck 88 is set in a state slightly lifted above the mirror surface 90. In the first inspection execution unit 80 shown in FIG.
When the QFP ICL is lifted from the mirror surface 90 by the rod 86 and positioned and held by the suction chuck 14,
The table 85 is moved to the measurement station 82 by forward rotation of the feed screw shaft 83 driven by the pulse motor B4. When the table 85 is positioned at the measurement station 82, the leads 3 protruding from both left and right sides of the package 2 are detected by the pair of left and right image capture devices 91A and 91B shown in FIGS. ,
The real image and the virtual image reflected on the mirror surface 90 are captured simultaneously by the image capture device 9]A and 91B, and each output signal of each camera 93 and 93 is transmitted to the image processing device 9.
Predetermined signal processing is performed in the image processing device 96 transmitted to the 8 image processing device 96, and as desired, images related to the real image and the virtual image of the 3 groups of leads are sequentially displayed on the monitor 97 as shown in FIG. Monitored. Further, in the image processing device 96, for example, based on the image signal as shown on the monitor 97 in FIG. Pn is determined by the process shown in FIG. That is, as shown in Fig. 2 (chrysanthemum), camera 9
A specific horizontal scanning line signal Sx is extracted from the image signal for either the real image A or the virtual image B for the lead 3 among the image signals from the lead 3. Next, as shown in FIG. 2(b), a bright I1g change point detection process is executed for this horizontal scanning line signal SX. Subsequently, as shown in FIG. 2(C), center positions X+, Xs...Xn corresponding to the center of each lead 3 are determined.
are measured by finding the center position between the points of change in brightness and darkness. After the center position of each lead 3 measured in this manner is stored, it is appropriately transmitted to the determination section 98 in accordance with a command. In the judgment section 9, first, the pitch dimension P between the adjacent leads 3.3, which corresponds to the distance between the center positions ZX and Xs, and between Xs and X, measured in this way, is determined.・
Pn is determined by the following equations. P= =X-X+, Pz =X3 K-...Pn=
Xn-Xn-+ Next, in the judgment section 9th, the actual measured values P, , P regarding the pitch obtained in this way. ... Pn and the setting value P sent from the setting section 99
o, and by checking whether the size of the difference is within the allowable value range, it is possible to determine whether the pitch P, , P, ... Pn between each lead 3 is appropriate. It is determined whether or not each of them is true. That is, when the difference value of Pn-Po is within the range of allowable values, it is judged as "good", and when the difference value of Pn-Pa is outside the range of allowable values, it is judged as "bad". Here, the set value Pa and the allowable value are preset in the setting section 99 based on the standard dimensions of the QFP/JCI as the object to be inspected. The determination result is output to an external device as necessary. At this time, according to this embodiment, it is possible to read the location of the defect and specify and indicate its error value, so in cases where the defect is repeatedly output at the same location, the cause of the defect can be discovered. Work can be speeded up. Next, in the image processing device 96, the tip position of each lead 3 in the real image and the tip position in the virtual image are determined by processing as shown in FIG. That is, first, as shown in FIG. 3(a),
Center position X of each lead 3 determined by the above-mentioned process
=, Xx ... Vertical image signal sz passing through Xn, ,
sz,...SZn are extracted, respectively. Next, as shown in FIG. The tip positions a l , a t ...an in A + , A z ...An, and the tip positions b in the corresponding virtual images B,, B, ...Bn
t, bz . . . are determined as coordinates as bn. After the real image tip position and virtual image position of each lead determined in this way are stored, the determining unit 9 and the setting unit 9
9 as appropriate in response to the command. First, the determination unit 98 calculates the difference between the real image tip position alba2 . . . an of each lead and the virtual image tip position bt, bz . 1 =al b+ Shz =az bz,・hn
=an-bn This difference value corresponds to the distance between the real image tip and the virtual image tip,
The larger this value is, the higher the lead is lifted from the mounting land surface, and the lead is bent radially outward. Furthermore, since the QFP/ICL is slightly lifted from the mirror surface 90 and held by the suction chuck 8, this interval dimension includes twice the floating dimension. Therefore, in the setting unit 99, a virtual reference plane coordinate position Yo is determined by the following formula for calculating the average position of the real image tip position and the virtual image tip position, and this position Yo is determined whether the lead is lifted from the mounting land surface or not. This is assumed to be a reference value for determining whether or not the lead is bent in the inward/outward direction. In other words, this virtual reference plane position Yo is the position of the reference line where the three groups of leads should be aligned in a straight line on the collar surface 90 on which the three groups of leads are mounted, that is, the position of the reference line where the five groups of lands are aligned when this ICI is mounted. corresponds to the position shown. Yo= (al +b,)/2 + (az +bz)/2 ・--(an+bn)7
2nd, in the judgment section 9, the distance dimensions actually measured as described above, h, . The difference from the interval from Yo is calculated one by one,
By checking from time to time whether the difference value is within the range of preset tolerance values that are also called,
It is determined whether each lead 3 is lifted from the mounting surface. For example, in FIG. 1, the fifth glue portion 3e from the left
is lifted upward, and as a result, hs becomes larger than the allowable range, so it is determined to be defective. The determination result is output to the external device 2S as necessary, and at that time,
The defective location and its error value are associated with each lead. Further, in the determination unit 98, the center line position 1jYo is called from the setting unit 99, and the tip position al, aZ in the real image of each lead is called from the image processing device 96.
...an, and the tip position Wb1, bt in the virtual image
...bn are called sequentially, and these tip positions al,
aZ...an, and b+, b□...bn, and the difference between center line position Yo, al -Yo%ax -Yo
...-an-Y. andsu, -Yo, bz-Yo -...bn-Y. is required from time to time. Then, whether or not the magnitude of these differences falls within a preset tolerance range is checked from time to time, thereby determining whether or not the inner and outer positions of each lead 3 are appropriate. For example, in Figure 1, the 7th lead 3 on the right side
h is the difference h7 between the real image tip position a and the virtual image tip position
is within the acceptable range, but a 9 Y . Since the difference da and the difference db between b and Yo are outside the range of allowable values (with a positive or negative tendency), it is determined that the curve is bent in one direction, either inward or outward. The determination result is output to an external device as necessary. At this time, the defective location and its error value can be associated with each lead, as described above. In the above-mentioned operation, when the image capturing operation is completed, the table 85 is once returned from the measurement station 82 to the setting/resetting station 81, and then moved to the setting/resetting station 81 again. Then, at the measurement stage 82, a second image capturing operation is performed. This redundant operation of image capture operations increases the accuracy of the inspection. Furthermore, since the measurement and inspection work after image capture is performed by electrical processing, it is processed in parallel with mechanical work such as moving, setting, and resetting of the workpiece 1 after image capture. By the way, in the image capture operation a1, the lead 3
When the illumination for the uptake i! i
Since shadows will be included in the i-image, the accuracy of image processing will be reduced.
Even if shadows of objects in adjacent spaces are formed in the captured image due to the influence of illumination on the front and rear sides adjacent to the left and right sides where A and 91B face each other,
Similarly, the accuracy of image processing is reduced. However, in this embodiment, since the illumination device 100 is configured to uniformly illuminate the portion 3 of each side surface, and the shielding plates 105 are disposed at each of the four corners, shadows that have an adverse effect The occurrence of is prevented, and as a result,
Deterioration in image processing accuracy is prevented. That is, in the lighting device 10 (l) according to the present embodiment,
The circular ring-shaped light a101 is the QFP as the object to be inspected.
-1cI are arranged concentrically right above the 1cI, and the upper reflector 103 and the lower reflector 04 respectively reflect the illumination light toward the three rows of leads on each side of the QFP/ICI package 2. As a result, each lead 3 is uniformly illuminated from all directions, and as a result, no shadows of the leads 3 or the package 2 are formed on the imaging screen. In addition, since the shielding plates 105 at the four corners face the corners of the QFP-ICI package 2, they block mutual interference of lighting in adjacent spaces, thereby preventing the occurrence of shadows due to adjacent spaces. can do. In this way, in this embodiment, the lighting device 100
QFP-ICI package 2 as an object to be inspected
By uniformly illuminating the three rows of leads on the four sides of the screen from all directions and blocking the influence of adjacent illumination spaces, it is possible to prevent shadows from forming on the image capture screen. Accuracy can be increased, and as a result, measurement and inspection accuracy can be increased. When the lead inspection is completed in the first inspection execution section 80 and the QFP-ICI as the inspected object is returned to the setting/resetting station 82, the QJ? The P-ICI is handled by the third handling device 71, and the second slider 37 is moved to the right.
One copy is sent to the setting/resetting station 111 of the test execution unit 110. In this second inspection execution section 110, the QFP-ICI as the object to be inspected performs a similar inspection on the three groups of leads on both the front and back sides of the package 2 by the same operation as the inspection operation in the first inspection execution section 8G described above. executed. Note that the test operation in the second test execution unit 110 is the same as that in the first test execution unit 80 described above, so a description thereof will be omitted. When the lead inspection is completed in the second inspection execution unit 110 and the QFP/ICI as the inspected object is returned to the setting/resetting station 111, the QFP/[CL as the workpiece is handled by the fourth handling device 72. . The work 1 handled by the fourth handling device 72 is transferred to the good product tray 20 or the defective product tray 25 of the unloading device 19 under the control of the X table 35 and the Y table 31. That is, if both the above-mentioned inspections in the first inspection execution unit 80 and the second inspection execution unit 110 determine that the product is non-defective, the QFP/ICI as the workpiece is transferred to the unloading device 19 shown in FIG. Good quality tray 20
It will be transferred to. In addition, if both or either one of the inspections is determined to be defective, the relevant Ql? P・IcL is the 8th
The defective products are transferred to the defective product tray 25 shown in the figure. Thereafter, by changing the operation, the QFPiCI of the uninspected product tray 14 in the loading device 13 is changed.
Lead inspection will be automatically performed sequentially for each. Then, when the inspection of the QFPtCt of the uninspected product tray 14 in the first stage is completed and the uninspected product tray 14 is empty, the control 21 of the X table 35 and the Y table 31
The first X-direction long rider 3G is operated, and the empty tray is handled by the tray handling device 141. The handled empty tray 17 is transferred to the temporary tray 16 by the movement of the tray handling device [41, as shown by the imaginary line in FIG. 8, and is transferred thereon. On the other hand, when the empty tray 17 is transferred by the tray handling device 41, the elevator 15 of the loading device 13 rises by one pitch, as shown in FIG.
The second uninspected product tray 14 is moved to a predetermined height. From then on, the QFP/tC stored in this uninspected product tray 14
The above-mentioned inspection is carried out for t, and when all the inspections for the QFP-ICL of this uninspected tray 14 are completed, the empty tray is moved to the temporary storage stand 1 by the above-described operation.
6, the next uninspected tray 14 is automatically supplied, and the operation is automatically continued thereafter. In addition, in the unloading device 19, when the first stage non-defective tray 20 is filled with non-defective QFP-ICI, the left and right tray position 1 determining claws 22 and 22 are moved outward as shown in FIG. The non-defective tray 20 is then transferred to the elevator 23. When the non-defective tray 20 is transferred, the elevator 23 is lowered one pitch to standby for the next unloading operation, and the non-defective tray 20 is unloaded into the storage section 2. On the other hand, when the non-defective tray 20 is unloaded, it is closed by the left and right positioning claws 22,22. Next, the system of X table 35 and Y table 3 [? The direction slider 36 is operated by the operator, and the tray handling device 4 is moved as shown in phantom lines in FIG.
1, the empty tray 17 on the temporary storage stand 16 is handled and transferred to the positioning claws 22 and 221 of the unloading device 19. Thereafter, the inspected non-defective products are sequentially unloaded onto the non-defective product tray 20, and when the non-defective product tray 20 is full,
Through the above-described operation, the full good tray 20 is unloaded into the storage section 21, and the next empty tray 17 is automatically supplied from the temporary storage stand 16 to the unloading device 19 as a good tray 20, and from then on, The operation continues automatically. Note that since the defective product tray 25 has a very low incidence of defective products, once the tray 25 is full of defective products,
It shall be replaced as appropriate by the operator. According to the embodiment described above, the following effects can be obtained. (1) An electronic device equipped with a surface-mounted package is faced parallel to a mirror surface, a real image and a virtual image of the lead group are continuously imaged by an imaging device, and the image signal is processed. It is possible to automatically measure the positional relationship of each lead of the device in the state at the time of mounting, and to automatically measure the positional relationship of each lead in the state at the time of mounting, which saves manual work. It is possible to automatically perform lead measurement work without having to do so. (2) Based on the measurement results of the positional relationship of each lead in (1) above, perform an external inspection for circumferential bending and pitch suitability of the lead, vertical deformation, and radial inward/outward bending. By doing this, it is possible to automate the visual inspection of the lead, which is the object to be inspected. It is possible to improve the quality and reliability of the JL device, and to increase the rate of appropriate mounting during automatic mounting on electronic devices that have passed this inspection. (3) By increasing the correctness of mounting electronic devices during automatic mounting through the inspection in (2) above, it is possible to promote the surface mounting of electronic devices, thereby creating a product that meets the demands for high-density mounting. can be provided. (4) By arranging an electronic device equipped with a surface mount package parallel to a mirror surface, capturing a real image and a virtual image of the lead group using an imaging device, and processing the image signals, it is possible to Lead with images alone
(circumferential direction), Y (radial direction), and Z (vertical direction) can be measured at the same time, significantly reducing the time required to measure the leads of electronic devices and the resulting visual inspection time. It can be shortened to (5) In (4) above, the only thing that actually consumes time is the time required to capture one screen of the lead group array, and the subsequent image processing can be performed electrically. By performing image processing in parallel with the imaging work, the setting and resetting work of the electronic device, and the loading and unloading work,
Measurement work time and inspection work time can be further shortened. (6) By installing multiple image capture devices, multiple screens of each lead row to be measured and inspected can be captured simultaneously, which further reduces measurement and inspection time. . By setting up multiple inspection execution units, it is possible to process the image capture work itself, as well as the entire measurement and inspection work that accompanies it, in parallel, making it possible to further shorten the measurement work time and inspection work time. (8) By configuring the illumination device to uniformly illuminate each lead row in the QFP-IC package from all directions, it is possible to prevent shadows from occurring on the screen taken in each lead. This prevents deterioration in image processing and inspection accuracy due to shadows.
As a result, the quality and reliability of the inspection itself and the object to be inspected can be improved. (9) By interposing a shielding plate for the illumination of adjacent spaces in the lighting device, it is possible to prevent mutual interference between adjacent spaces, so shadows in the image capture screen due to the influence of adjacent spaces can be prevented. This can be prevented, and as a result, the effect of (8) above can be further enhanced. 0ω By being equipped with a loading device for workpieces to be inspected, an unloading device for inspected non-defective products and defective products, and various handling devices for transporting these workpieces, measurement and inspection work can be carried out automatically for a long period of time. The productivity of measurements and inspections can be increased. (By performing measurement and inspection work with the IDQFP/tC slightly lifted from the mirror surface, it is possible to prevent the wire from being deformed during work, improving the quality and reliability of lead inspection. ■ By incorporating a lead repair device, it is possible to inspect the leads while carrying out repair work, increasing the pass rate of lead inspections and reducing the lead inspection and inspection object. The invention made by the present inventor has been specifically explained based on the examples above, but the present invention is not limited to the examples described above, and there is no need to deviate from the gist of the invention. Needless to say, various changes can be made as long as the lead inspection execution unit is not set in 2ti. The image capture devices are not limited to being installed in a pair in a pair of inspection execution units, but may be installed in pairs in a single inspection execution unit, or may be installed in two pairs in a single inspection execution unit, or may be installed in pairs that work independently of each other as appropriate. Multiple units may be installed.The structure is not limited to measuring and inspecting the leads with the object to be inspected suspended above the mirror surface, but also measuring and inspecting the leads with the object to be inspected placed on the mirror surface. The loading device, unloading device, handling device, lead correction device, etc. are not limited to those shown in the above embodiments, and may be omitted as appropriate depending on the degree of automation required. Furthermore, the specific configurations of the imaging device, the chuck that positions and holds the inspected object, the image processing device, the monitor, the determination unit, and the setting unit are not limited to those shown in the above embodiments.
It is desirable that the selection be made appropriately in accordance with specific conditions such as the shape, structure, size, etc. of the object to be inspected. In the embodiment described above, a case has been described in which the lead measuring device is incorporated into a lead testing device and used in a lead testing method. It can also be used to measure the amount of bending of the lead in the radial direction, the amount of lifting of the tip of the lead, etc., and its uses are not limited. In the above explanation, we have mainly explained the case where the invention made by the present inventor is applied to the lead inspection technology of QFP-IC, which is the field of application which is the background of the invention, but it is not limited to this. Package (MSP) Ic, Plastic Relid Chip
Carrier (PLCC) Ic, Small Outline
Package (SOP) IC, small outline
J lead package (SOJ) IC, small outline ■Lead package (S. 1) IC2 and other lead inspection technology and lead measurement technology for electronic components and electronic equipment equipped with surface mount packages. It can also be applied, if necessary, to lead inspection technology and lead measurement technology for electronic devices equipped with insert-type external terminals, such as ICs with dual in-line packages. be able to. In particular, the present invention can be applied to lead inspection techniques for ICs equipped with surface-mounted packages, and excellent effects can be obtained. [Effects of the Invention] A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows. Electronic devices equipped with surface-mount packages are placed face-to-face in parallel, and a real image and a virtual image of the lead group are imaged by a single image device, and the image signals are processed, thereby each of the electronic devices is It is possible to automatically measure the positional relationship of each lead in the mounting state before mounting, assuming the positional relationship of the leads at the time of mounting. measurement tasks can be performed automatically.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing a lead inspection device which is an embodiment of the present invention, Figs. 2 and 3 are explanatory diagrams for explaining its operation, and Figs. 4 and 5 show an object to be inspected. Fig. 6 is a perspective view showing the overall appearance of the lead inspection device, Fig. 7 is its plan view, and Fig. 8 shows the loading device and unloading device. FIG. 9 is a plan view showing the handling device; FIG. 10 is a partially cut-away side view of the handling device; FIG. 11 is a schematic front view showing the lead correction device; FIG. 13 is a partially cutaway front view showing the measuring station, and FIG. 14 is a partially cutaway plan view thereof. 1...QFP/IC (electronic device, product to be inspected), 2...
・Resin-sealed package, 3... Outer lead, 4...
・Print arrangement 51 board, 5... land, 6... solder mound i, tt... 8 units, 12... rail, 13
... Loading equipment H514 ... Uninspected tray 1
5...Elevator, 16...Empty tray temporary storage stand, 17
...Empty tray 18...Rail, 19...Unloaded in l"Jl, 20...Good tray, 21...
- Storage section, 22... Tray positioning claw, 23... Elevator, 24... Defective product tray placement stand, 25... Defective product tray, 31... Y table, 32... Y direction slider, 33... Rail, 34... Y direction slider, 35... X table, 36... Second X direction slider, 37... Second X direction slider, 40... Base, 41... Tray Handling device for 42...
Guide, 43... Vertical slider, 44... Bracket, 45... Cylinder device, 46... Piston rod, 47... Vacuum suction head, 48... Negative pressure supply path, 50...・First handling device for workpiece, 51
... IT guide rail, 52 ... Vertical slider, 53 ... First hand for work, 54 ... First suction hand, 55 ... Negative pressure supply path, 56 ... Bracket, 57... Cylinder holder for first suction head, 58...
- Piston rod, 59... Connection member, 60... Second handling device for work, 61... Second guide rail, 62... Vertical slider, 63... Second hand for work, 64 ...Second suction head, 65...
Negative pressure supply path, 66... Bracket, 67... Cylinder device for second suction head, 68... Piston rod,
69... Connection member, 71... Third handling device for work, 72... Fourth handling device for work,
73... Lead correction device, 74... Upper mounting plate, 7
5... Upper mounting plate, 76... Upper die, 77... Lower die, 78... Vacuum suction head, 79... Positioning claw,
80...First inspection execution unit, 81...Loading/
Unloading station, 82... Measuring station, 83... Feed shaft, 84... Pulse motor, 85... Table, 86... Rod, 87...
- Drive device, 88... Adsorption chunk, 89... Negative pressure supply path, 90... Mirror surface, 9]A, 91B... Image capture device, 92... Lens barrel, 93... Camera , 94
...Lens, 95...Reflector, 96...Image processing device, 97...Monitor, 98...Judgment unit, 99...
- Setting section, 100... Lighting device, 101... Dark box,
102...Light source, 103...1 reflecting mirror, 104...
- Lateral reflecting mirror, 105... Shielding plate, 110... Second inspection execution unit, 111... Setting/resetting station, 112... Measurement station, l13
A, 113B... Image capture device, 114... Illumination device. Figure 2 (Q) Agent: Patent attorney Tatsuya Kajihara? lυsa1 Figure 3 (G) I! Ward 4, Figure 5, Figure 9! J

Claims (1)

[Scope of Claims] 1. A lead inspection method for inspecting the positional relationship of a group of leads in an electronic device equipped with a surface mount package, the method comprising: arranging the electronic device parallel to a mirror surface; The real image of the lead group and the virtual image reflected on the mirror surface are respectively imaged from a plurality of directions while facing each other, and the real image and the virtual image of the lead are compared, respectively, based on each image signal of the real image and the virtual image. , measure the center position, real image tip position, and virtual image tip position of each lead, respectively, and further, based on this measurement data, determine the pitch of each lead, the interval between the real image tip position and the virtual image tip position, and, A lead inspection method characterized by determining the difference between at least the real image or virtual image tip position and a reference position, and inspecting the positional relationship of each lead in the circumferential direction, vertical direction, and radial direction. 2. A lead measuring device for measuring the positional relationship of a group of leads in an electronic device equipped with a surface mount package, the device being disposed on the mounting surface side of the group of leads, with at least a part thereof facing the real image thereof. a mirror surface for reflecting the image; and a holding means for holding the electronic device in a state parallel to the mirror surface;
A plurality of imaging devices each image a real image of the lead group and a virtual image reflected on the mirror surface from different directions, and the leads are imaged based on image signals for the real image and virtual image of each imaging device. A lead measurement method comprising: an image processing device that compares a real image and a virtual image of the electronic device to measure the mutual positional relationship between the lead groups; and an illumination device that uniformly illuminates each lead group of the electronic device. Device. 3. A lead inspection device for inspecting the positional relationship of a group of leads in an electronic device equipped with a surface mount package, the device being disposed on the mounting surface side of the group of leads, with at least a portion thereof facing the real image thereof. a mirror surface for reflecting the image; and a holding means for holding the electronic device in a state parallel to the mirror surface;
A plurality of imaging devices each image a real image of the lead group and a virtual image reflected on the mirror surface from different directions, and the leads are imaged based on image signals for the real image and virtual image of each imaging device. an image processing device that compares a real image and a virtual image of the electronic device, respectively, and measures the positional relationship between the lead groups; an illumination device that uniformly illuminates each lead group of the electronic device; Then, for each lead, find the pitch, the distance between the real image tip position and the virtual image tip position, and at least the difference between the real image or virtual image tip position and the reference position, and calculate the positional relationship of each lead in the circumferential direction, vertical direction, and radial direction. A lead inspection device comprising: a determination section that determines.