JP4653568B2 - Method and apparatus for visual inspection of surface mount substrate - Google Patents

Description

The present invention relates to an inspection method and apparatus using the quality of such mounting and soldering of surface mount board to determine visual inspection.

Determining visual inspection the quality of the inspected object, such as mounting and soldering electronic parts mounting surface mount board such as IC chips is shot with inspection camera to be inspected from above, it captured the A method has been adopted in which an image to be inspected is enlarged and displayed on a monitor screen. However, when the object to be inspected is, for example, soldering, it is difficult to detect a defect such as a so-called floating of the terminal of the IC chip in the image inspection only from directly above. A method is adopted in which an image is taken from a predetermined tilt angle direction, that is, the terminal of the IC chip is taken from the horizontal direction, and this image is enlarged and displayed on a monitor screen (Non-patent Document 1, Patent) Reference 1).
FIG. 3 shows an apparatus 100 that employs the above-described inspection method so that the inspection camera 101 is tilted by a predetermined inclination angle and can be photographed from the predetermined inclination angle direction. , The drum 103 is attached to substantially the center of the shaft 102 whose axis is the virtual perpendicular line X passing through the IC chip W having terminals a to c). A thin plate blade 106 is fixed to the shaft 102 directly below the shaft 103 where the drum 103 is mounted. The blade 106 is bent at a predetermined angle from the center to the other end, the inspection camera 101 is attached to the lower surface of the bent portion at the other end, and the optical axis of the inspection camera 101 is the virtual perpendicular described above. A predetermined inclination angle is formed with respect to X. Reference numeral 107 denotes a bearing that supports the shaft 102.
In such an apparatus 100, as shown in FIG. 4, the inspection target of the IC chip W (to be soldered at the terminals a to c of the IC chip W) rotates (revolves) as the shaft 102 rotates. The image is taken by the camera 101 and enlarged and displayed as an oblique projection image on the monitor screen. In FIG. 4, images from four directions among such images, that is, images from the front side direction, the back side direction, the left side direction, and the right side direction (hereinafter referred to as the front side image and the back side image). , Left side image and right side image). Needless to say, unless the image is processed by software or the like, usually, the above-described images on the opposite side are individually displayed on the monitor screen.

However, in the image photographed by the above-described conventional apparatus, as shown in FIG. 4, for example, the position of the terminal a of the IC chip W in the directly-facing side image is the other back-side image or left-side image. The position of the terminal a displayed in the right side image is different from each other (for example, the terminal a in the left side image appears on the left side and the terminal a in the right side image appears on the right side). When the visual inspection of the terminal a is performed by sequentially switching these images, the inspection of the terminal a must be performed while always checking the position of the terminal a (actually marking or the like). is there. Needless to say, the number of terminals of a normal IC chip W is extremely large, and as the number of terminals increases, the complexity of this type of inspection becomes extremely small, and the above-described conventional apparatus becomes extremely inconvenient. It was. Therefore, in the past, in order to eliminate such inconvenience, there has been a case in which image processing by software or the like is performed to obtain an image described later of the present invention.
Visual inspection support system NEOVIEW catalog Hitachi Giken, Ltd. As of September 2004 JP 2001-255274 A (5th and 6th pages, FIG. 1)

A problem to be solved is, when electronic components such as an IC chip to enlarge to an image of the inspection object, such as mounting and soldering of surface mount board that is mounted on the monitor screen test, good usability An image can be easily displayed on a monitor screen without image processing by software or the like.

Appearance inspection method according to claim surface mount board according to the first invention, upon visual inspection determines the quality of the inspected object, such as mounting and soldering of surface mount board on which the IC chip or the like is mounted, the object to be a visual inspection method of a virtual perpendicular line to enlarge to the image of the object to be inspected obtained by the inspection camera for photographing from a direction forming a predetermined inclination angle on the monitor screen inspection through the inspection object to be inspected article The oblique projection image that is photographed without changing the directly-facing position of the object to be inspected from any direction while rotating the inspection camera is displayed on the monitor screen and inspected. As a result, the directly-facing position of the object to be inspected does not change not only in the directly-facing image but also in the back-side image, the left-side image, and the right-side image. Usability with is improved, such as by being subjected to image processing software will conveniently order not require a step so as to obtain a desired image.

Appearance inspection apparatus of the surface mount board according to claim 2 of the present invention, upon visual inspection determines the quality of the inspected object, such as mounting and soldering of surface mount board on which the IC chip or the like is mounted, the object to be in the appearance inspection apparatus for enlarge to test the monitor screen image of the object to be inspected obtained by the inspection camera for photographing from a direction forming a predetermined inclination angle with respect to a virtual vertical line passing through the test object to be inspected article The inspection camera revolves around the virtual perpendicular with a predetermined inclination angle, and is equivalent to the revolving angle around the optical axis forming the predetermined inclination angle, and the revolving direction. Thus, the directly facing position of the object to be inspected is changed not only in the directly facing image, but also in the back side image, the left side image, and the right side image, for example. Because there is no Together with the usability of the image displayed on the coater screen is improved, can be displayed on easily monitor screen without image processing such an image software, such as.

Appearance inspection apparatus of the surface mount board according to claim 3 of the present invention disposed rotatably blades around said virtual perpendicular line, rotatably mounting shaft of the inspection camera at one end of the blade A first pulley that is fixed so that its axis coincides with the virtual perpendicular line, and a second pulley that has the same diameter as the first pulley and is fixed on the mounting shaft of the inspection camera. A structure in which a winding member is stretched between them is one aspect of a more specific embodiment.

Visual inspection method and apparatus for surface mount board of the present invention, enlarged display to the image of the inspection object, such as mounting and soldering of surface mount board on which an electronic component such as an IC chip is mounted on the monitor screen When inspecting, the position of the object to be inspected in the image on the opposite side can be displayed on the monitor screen without changing any of the back side image, left side image, right side image, etc. In addition, a user-friendly image can be easily obtained without performing image processing with software or the like.

The visual inspection method and apparatus for surface mount board according to the embodiment of the present invention will be described with reference to FIGS.
The appearance inspection apparatus 1 has a configuration as shown in FIG. 1 and, for example, terminals a to b of a product to be inspected (simply represented by IC chips W having terminals a to c in FIGS. 1 and 2). Photographed to be inspected such as soldered state in c, and used for appearance inspection to enlarge and display an image of the inspected object on the monitor screen or the like to determine the quality of the inspected object It is.
A specific configuration of the appearance inspection apparatus 1 will be described with reference to FIG.
In the appearance inspection apparatus 1, a main shaft 2 having a virtual perpendicular line X passing through an IC chip W of a product to be inspected as an axis is rotatably supported by a bearing 3 disposed on the upper end side of the main shaft 2. A thin cylindrical drum 4 is attached to the center of the main shaft 2, and one end of a thin plate blade 5 having a substantially central portion bent is attached to the lower end side of the main shaft 2. The outer periphery of the drum 4 is recessed, and a belt 6 is wound around a part of the recess. On the other hand, the belt 6 is wound around the output shaft of the motor 7, whereby the main shaft 2 is driven to rotate by the motor 7. It has become so. Further, as described above, the blade 5 is bent at a substantially central portion at a predetermined angle, and the other end (one end) is a slave shaft (a mounting shaft for an inspection camera) via a bearing (not shown). ) 8 is rotatably supported. An inspection camera 9 is attached to the lower end side of the slave shaft 8, and a second pulley 10b is pivotally attached to the upper end side. Such an axis of the slave shaft 8 is relative to the axis of the main shaft 2, in other words, the optical axis of the inspection camera 9 has a predetermined inclination angle with respect to the virtual perpendicular X.

  Further, in the appearance inspection apparatus 1, the first pulley 10a that is paired with the second pulley 10b has the drum 4 so that the axis of the first pulley 10a coincides with the axis of the main shaft 2. It is fixed by a fixing member (not shown) in such a manner that it is disposed around the main shaft 2 located at a substantially intermediate position between the portion where the blade 5 is attached and the portion where the blade 5 is attached. A pulley 11a such as a belt or a rope is stretched between the pulley 10a and the second pulley 10b having the same diameter as the pulley 10a to connect the pulleys 10a and 10b. In the present embodiment, the axis of the main shaft 2 and the axis of the driven shaft 8 correspond to the fact that the virtual perpendicular X and the optical axis of the inspection camera 9 form a predetermined inclination angle. The guide roller 12 is disposed between the pulleys 10a and 10b near the bent portion of the blade 5, the winding member 11 is pressed against the guide roller 12, and the winding member is brought into contact with the guide roller 12. 11 is an embodiment in which the bent portion of the blade 5 is bent in accordance with the predetermined angle.

Next, an inspection method using the appearance inspection apparatus 1 will be described with reference to FIGS.
However, for convenience of explanation, the product to be inspected is an IC chip W, and soldering at the terminal a of the IC chip W is the object to be inspected. In FIG. 2, the facing image, the right side image, the back side image, and the left side image that are displayed one by one on the monitor screen are displayed together.
In the present embodiment, the inspection camera 9 of the appearance inspection apparatus 1 is started to face the IC chip W and the IC chip W at the facing position is photographed. Then, the photographed IC chip W is displayed on the monitor screen as an obliquely projected front-side image as shown in FIG. 2A, and the soldered state of the terminal a in this image is inspected. When attention is paid to the terminal a appearing in the directly facing image at this time, the terminal a appears above the screen. Next, the inspection camera 9 is rotated 90 ° counterclockwise as indicated by the arrow in FIG. 1 from the position facing the IC chip W by rotating the spindle 2 with the motor 7. That is, the inspection camera 9 is revolved 90 ° around the virtual perpendicular line X in the counterclockwise direction. Then, the inspection camera 9 rotates 90 ° in the clockwise direction indicated by the arrow in FIG. That is, the inspection camera 9 rotates around the optical axis in a direction equivalent to the revolution angle and in a direction opposite to the revolution direction. Here, when the IC chip W is photographed, the photographed IC chip W is displayed on the monitor screen as an obliquely projected right side image as shown in FIG. 2B. Therefore, the solder of the terminal a in this image is displayed. Check the attachment status. When attention is paid to the terminal a appearing in the right side image at this time, the terminal a appears at the upper part of the screen as in the case of the above-mentioned facing side image, and is taken from the right side direction by the inspection camera 9. Also, the image is taken without changing the directly facing position of the IC chip W. That is, even if the inspection object is photographed from the right side by the inspection camera 9, the object is photographed without changing the directly facing position.

Then, the inspection camera 9 is further rotated by 90 ° in the counterclockwise direction indicated by the arrow in FIG. That is, the inspection camera 9 is revolved 90 ° around the virtual perpendicular line X in the counterclockwise direction. Then, the inspection camera 9 further rotates 90 ° in the clockwise direction indicated by the arrow in FIG. That is, the inspection camera 9 rotates around the optical axis in a direction equivalent to the revolution angle and in a direction opposite to the revolution direction. Here, when the IC chip W is photographed, the photographed IC chip W is displayed on the monitor screen as an obliquely projected back side image as shown in FIG. 2C. Therefore, the solder of the terminal a in this image is displayed. Check the attachment status. When attention is paid to the terminal a appearing on the back side image at this time, the terminal a appears on the upper side of the screen as in the case of the above-mentioned facing side image or the like, and is taken from the back side direction by the inspection camera 9. However, the image is taken without changing the directly facing position of the IC chip W. That is, even if the inspection object is photographed from the back side direction by the inspection camera 9, it is photographed without changing the directly facing position of the inspection object. Similarly, when the inspection camera 9 is further rotated by 90 ° in the counterclockwise direction indicated by the arrow in FIG. 1 by rotating the main shaft 2 by the motor 7, the inspection camera 9 is rotated along with the rotation of the slave shaft 8. It is further rotated by 90 ° in the clockwise direction indicated by the arrow in FIG. Here, when the IC chip W is photographed, the photographed IC chip W is displayed on the monitor screen as an obliquely projected left side image as shown in FIG. 2D. Therefore, the solder of the terminal a in this image is displayed. Check the attachment status. When attention is paid to the terminal a appearing on the left side image at this time, the terminal a appears on the upper side of the screen in the same manner as in the above-mentioned facing side image or the like, and is taken from the left side direction by the inspection camera 9. However, the image is taken without changing the directly facing position of the IC chip W. That is, even if the inspection target is photographed from the left side by the inspection camera 9, it is photographed without changing the directly facing position of the inspection target.
As described above, in this appearance inspection apparatus 1, even if the object to be inspected is imaged from any direction, an oblique projection image that is imaged without changing the directly-facing position of the object to be inspected is displayed on the monitor screen. Since it can be inspected, it is very easy to use.

  In the present embodiment, the case where the optical axis of the inspection camera 9 has a predetermined inclination angle (constant) with respect to the virtual perpendicular X has been described. However, the inclination angle can be changed depending on the object to be inspected. For example, the predetermined angle of the bent portion of the blade 5 may be changed.

The present invention, when an electronic component such as an IC chip to enlarge to an image of the inspection object, such as mounting and soldering of surface mount board that is mounted on the monitor screen test, the object to be inspected in the confronting side image Can be displayed on the monitor screen without changing the image taken from either direction, so that it is easy to use and easy-to-use images without software processing etc. It can be said that it can be widely used for this kind of inspection.

It is a composition perspective view of the appearance inspection device concerning an embodiment of the invention. It is an image figure of the to-be-inspected object image | photographed with the apparatus of FIG. 1 and displayed on the monitor screen. It is a structure perspective view of the conventional external appearance inspection apparatus. It is an image figure of the to-be-inspected object image | photographed with the apparatus of FIG. 3 and displayed on the monitor screen.

Explanation of symbols

1 Appearance inspection device 5 Blade 8 Slave shaft (Inspection camera mounting shaft)
9 inspection camera 10a first pulley 10b second pulley 11 winding member W IC chip (inspected product)

Claims (3)

Upon determining visual inspection the quality of the inspected object, such as mounting and soldering of surface mount board on which the IC chip or the like is mounted, the virtual perpendicular line passing through the object to be inspected article to be inspected to form a predetermined inclination angle An appearance inspection method in which an image of an inspection object obtained by an inspection camera that captures images from a direction is enlarged and displayed on a monitor screen, and the inspection object is captured from any direction while rotating the inspection camera the oblique projection images taken without confronting position to be inspected is changed, the appearance inspection method of the surface mount board, characterized in that the inspection displayed on the monitor screen even if. Upon determining visual inspection the quality of the inspected object, such as mounting and soldering of surface mount board on which the IC chip or the like is mounted, the virtual perpendicular line passing through the object to be inspected article to be inspected to form a predetermined inclination angle An appearance inspection apparatus for inspecting an image of an object to be inspected obtained by an inspection camera photographed from a direction enlarged on a monitor screen, wherein the inspection camera has a predetermined inclination angle around the virtual perpendicular while revolving form, around the optical axis which forms the predetermined inclination angle, and equivalent to the angle of the revolution, and the appearance of the surface mount board, characterized in that the the direction of revolution rotates in the opposite direction Inspection device. A blade is disposed so as to be rotatable around the virtual vertical line, and the mounting shaft of the inspection camera is rotatably supported at one end of the blade, and fixed so that the axis of the blade coincides with the virtual vertical line. 3. A winding member is stretched between the first pulley and the second pulley having the same diameter as the first pulley and attached to the mounting shaft of the inspection camera. appearance inspection apparatus of the surface mount board according to.

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