Electric characteristics measurement system and electric characteristics measurement method

Abstract

To provide an electric characteristics measurement system which enables easy registration of measurement position information, and which excels in work efficiency, and an electric characteristics measurement method using this system.SOLUTION: An electric characteristics measurement system 1 comprises: an information processing apparatus 2 registering measurement position information which is information on a measurement position in a circuit board; and a testing device 9 measuring electric characteristics of the circuit board on the basis of the measurement position information registered by the information processing apparatus 2. The testing device 9 includes a measurement table on which the circuit board can be placed, and measurement means having a probe which can horizontally move with respect to the circuit board placed on the measurement table and comes in contact with a measurement position on the circuit board, and measures electric characteristics. The information processing apparatus 2 has a display portion 4 and registers measurement position information by selecting a measurement position on the display portion 4 which has displayed image information of the circuit board.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrical characteristics measurement system that can automatically measure the electrical characteristics of a printed circuit board or the like, and an electrical characteristics measurement method that uses the same. [Background technology]

[0002] Printed circuit boards (hereinafter also referred to as circuit boards) are inspected for electrical characteristics such as wiring continuity during the production process and after the product is completed. In printed circuit board manufacturing factories, inspections may be performed manually for small-lot production, while mass-produced products are often inspected using specialized inspection equipment. Furthermore, for example, in testing laboratories that test electrical equipment, manual inspections are often performed because tests are performed on a variety of devices with different wiring positions and electronic component arrangements on the board. As high-mix, low-volume production of printed circuit boards progresses, devices that can easily and quickly inspect the continuity of wiring on printed circuit boards are becoming increasingly important.

[0003] As an example of an apparatus for inspecting printed circuit boards, Patent Document 1 describes a printed circuit board wiring inspection device that includes a spring-loaded pin equipped with an inspection needle, an XY-axis control device that moves the spring-loaded pin, and a continuity tester that measures resistance values.

[0004] Furthermore, Patent Document 2 describes a printed wiring board wiring inspection device that includes a data processing device equipped with a net information extraction unit that extracts information about nets, which are connections between terminals; a mobile inspection probe control device that controls the inspection probe based on output information from the data processing device; and an electrical detection device that detects electrical information from the inspection probe and determines whether it is conductive or non-conductive. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2-136759 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-33505 Summary of the Invention [Problem to be solved by the invention]

[0006] Patent Document 2 describes that when actually performing measurements, first, information on the wiring pattern (conductor) of the printed wiring board, hole position information, solder resist information, etc. are input, and based on this information, the end points where the conductor is exposed, i.e., the inspection points, are extracted for each net.

[0007] When inspection is performed using conventional inspection equipment, electrical measurements themselves can be performed automatically, but it is thought that input of wiring pattern information, hole position information, etc. must be done manually using a keyboard, etc. Therefore, for example, when hole position information is entered and registered as numerical coordinate information, there is a risk of inputting incorrect information or that preparation work before measurement takes time.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide an electrical characteristic measurement system that allows measurement position information to be easily registered and is easy to use, and an electrical characteristic measurement method using the same. [Means for solving the problem]

[0009] The electrical characteristic measurement system of the present invention is an electrical characteristic measurement system for measuring the electrical characteristics of a circuit board, and this system comprises an information processing device that registers measurement position information, which is information about measurement positions on the circuit board, and a test device that measures the electrical characteristics of the circuit board based on the measurement position information registered by the information processing device, and the test device has a measurement stand on which the circuit board can be placed, and a measurement means that is movable horizontally relative to the circuit board placed on the measurement stand and has a probe for contacting a measurement position on the circuit board to measure the electrical characteristics, and the information processing device has a display unit and has a function of registering the measurement position information by selecting a measurement position on the display unit that displays image information of the circuit board.

[0010] The image information of the circuit board is information acquired in advance before the circuit board is placed on the measurement table, and is characterized by having a function of correcting the inclination of the image information of the circuit board when registering the measurement position information.

[0011] The measuring means is characterized by having a probe support portion that supports the probe so that the probe can be displaced upward, and an elevation means that moves the probe support portion in the height direction above the circuit board.

[0012] The image information of the circuit board is information acquired after the circuit board is placed on the measurement table.

[0013] The electrical characteristic measurement method of the present invention is an electrical characteristic measurement method that utilizes an electrical characteristic measurement system that measures the electrical characteristics of a circuit board, and the electrical characteristic measurement method comprises an image information acquisition process that acquires image information of the circuit board, and a measurement position registration process that registers measurement position information, which is information about the measurement position on the circuit board, and is characterized in that in the measurement position registration process, the measurement position information is registered by selecting a measurement position on a display unit of the electrical characteristic measurement system that displays the image information of the circuit board.

[0014] The method is characterized in that it includes a board installation step of installing the circuit board on a measurement table before the image information acquisition step, and the image information acquired in the image information acquisition step is image information of the circuit board installed on the measurement table. [Effects of the Invention]

[0015] The electrical characteristic measurement system of the present invention includes an information processing device that registers measurement position information, which is information about measurement positions on a circuit board, and a test device that measures the electrical characteristics of the circuit board based on the measurement position information registered by the information processing device. The test device has a measurement table on which the circuit board can be placed and measurement means that is movable horizontally relative to the circuit board placed on the measurement table and has a probe that contacts the measurement position on the circuit board to measure the electrical characteristics. The information processing device has a display and a function for registering the measurement position information by selecting the measurement position on the display that displays image information of the circuit board. This eliminates the need to enter the measurement position information as a numeric value using a keyboard or the like, and allows the measurement position information to be registered simply and accurately. This improves operability when measuring the electrical characteristics of the circuit board.

[0016] The image information of the circuit board is information acquired in advance before the circuit board is placed on the measurement table, and has the function of correcting the tilt of the image information of the circuit board when registering the measurement position information, so that the probe can be brought into contact with the measurement position more accurately, and electrical characteristics can be measured with high precision.

[0017] The measuring means has a probe support section that supports the probe so that it can be displaced upward, and an elevation means that moves the probe support section in the vertical direction above the circuit board, so that the probe can contact the conductive section at the measurement position so as to follow the uneven shape of the conductive section, thereby enabling more accurate measurement of electrical characteristics.

[0018] Since the image information of the circuit board is acquired after the circuit board is placed on the measurement table, the number of steps during measurement can be reduced and measurement position information can be registered easily, resulting in improved workability when measuring the electrical characteristics of the circuit board.

[0019] The electrical characteristic measuring method of the present invention comprises an image information acquiring step of acquiring image information of a circuit board, and a measurement position registering step of registering measurement position information, which is information about measurement positions on the circuit board, and in the measurement position registering step, the measurement position information is registered by selecting the measurement position on a display unit of the electrical characteristic measuring system that displays the image information of the circuit board, which eliminates the need to input the measurement position information as a numerical value using a keyboard or the like and allows the measurement position information to be registered easily, thereby improving workability when measuring the electrical characteristics of a circuit board.

[0020] The method includes a board installation step of installing the circuit board on a measurement table before the image information acquisition step, and the image information acquired in the image information acquisition step is image information of the circuit board installed on the measurement table, so that the number of steps during measurement can be reduced compared to when image information is acquired before installation on the measurement table, and measurement position information can be registered easily, resulting in better workability during measurement. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating an example of the overall configuration of an electrical characteristic measuring system. [Figure 2] FIG. 1 is a perspective view showing an example of a testing device. [Figure 3] 3 is a flowchart showing the flow of the electrical characteristic measuring method according to the first embodiment. [Figure 4] 1A and 1B are diagrams illustrating a circuit board before and after correction. [Figure 5] FIG. 10 is a diagram showing an example of a screen for setting a scale. [Figure 6] FIG. 10 is a diagram showing an example of a screen when registering a measurement position. [Figure 7] FIG. 10 is a diagram showing an example of a measurement screen. [Figure 8]10 is a flowchart showing the flow of an electrical characteristic measuring method according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] The electrical characteristic measurement system of the present invention will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the overall configuration of the electrical characteristic measurement system. The electrical characteristic measurement system 1 is a system that can be used to measure the electrical characteristics (e.g., voltage, current, resistance, impedance, etc.) of wiring on a circuit board, electronic components, etc.

[0023] 1, the electrical characteristic measurement system 1 includes an information processing device 2 and a test device 9. The information processing device 2 and the test device 9 may be communicatively connected via a network to exchange information, or may exchange information via an information storage device such as a USB memory without using a network. For example, measurement conditions (e.g., measurement position information, probe movement speed, measurement order at each measurement position, etc.) and measurement result information (e.g., voltage value, current value, resistance value, impedance value, etc.) are transmitted and received between the information processing device 2 and the test device 9. When information is exchanged over a network, the network is configured using a telecommunications line such as a LAN line or the Internet line.

[0024] The information processing device 2 is an information processing device mainly configured with a microcomputer including a known CPU, ROM, RAM, etc. The information processing device 2 operates as various functional units by executing software stored in a storage unit. In FIG. 1, the information processing device 2 includes an image acquisition unit 3, a display unit 4, an input unit 5, a database 6, an output unit 7, and a storage unit 8. The information processing device 2 is a device that measures electrical characteristics based on information input via the input unit 5.

[0025] The information processing device 2 has the function of registering measurement position information, which is information about measurement positions on a circuit board, by operating the following units. The image acquisition unit 3 acquires two-dimensional and three-dimensional image information of the circuit board from imaging means such as a two-dimensional camera or a three-dimensional camera. If the imaging means is a three-dimensional camera, height information on the surface of the circuit board can also be acquired, allowing for more precise control of the contact of the probe P (described below) with the measurement position not only in the horizontal direction but also in the vertical direction. The image acquisition unit 3 can acquire image information from a memory unit inside the imaging means or from another memory unit to which information has been transferred after imaging by the imaging means.

[0026] The display unit 4 displays the acquired image information. Measurement position information is registered by using the input unit 5 to select a measurement position on the display unit 4 that displays the image information of the circuit board. The input unit 5 can be, for example, a pointing device such as a mouse, trackball, touch screen, or touch pad, or a keyboard. In addition to measurement position information, the input unit 5 can also be used to input information such as the probe movement speed and the measurement order for each measurement position. The information processing device 2 can accurately measure the distance between patterns at the measurement position from the image information of the circuit board. Based on this distance between patterns, a criterion to be used for inspecting electrical characteristics can be obtained. At the same time, evidence that the criterion has been obtained by measuring the distance between patterns from the image information can also be registered.

[0027] The database 6 stores image information, measurement position information, and information related thereto. The output unit 7 outputs information required for a purpose (such as measuring electrical characteristics or generating a program) based on the information in the database 6. The output unit 7 can generate a program for moving the measuring means (described later) to the measurement position and for the measurement procedure, and output a command to the test device 9 to measure the electrical characteristics at the measurement position. The storage unit 8 stores information such as the image information acquired by the image acquisition unit 3 and the measurement position information received by the input unit 5 in the database 6. Note that the information processing device 2 does not need to include the storage unit 8, and for example, the output unit 7 may have that function.

[0028] The test apparatus will be described with reference to FIG. 2. FIG. 2 is a perspective view showing an example of the test apparatus. The test apparatus 9 is an apparatus that measures the electrical characteristics of a circuit board Cb based on measurement position information registered by an information processing device. As shown in FIG. 2, the test apparatus 9 includes an apparatus main body 90, a measurement table 91 on which the circuit board Cb can be placed, a measurement means 92 having a probe P for contacting a measurement position on the circuit board Cb to measure the electrical characteristics, and a horizontal movement means 93 that moves the measurement means 92 in the horizontal direction. The measurement means 92 is provided on the horizontal movement means 93 and can move in the horizontal direction (X and Y directions) relative to the circuit board Cb placed on the measurement table 91. Note that in FIG. 2, wiring connected to the probe P is omitted.

[0029] The test apparatus 9 is installed by placing the apparatus main body 90 on a horizontal mounting table. In FIG. 2, a measurement table 91 on which a circuit board Cb is placed is provided within an area where a measurement unit 92 of the test apparatus 9 can move. The circuit board Cb is placed on the measurement table 91 with the side where the probe P contacts and the electrical characteristics are measured facing up. The circuit board Cb is preferably fixed to the measurement table 91 with, for example, screws or adhesive tape to prevent movement of the placed circuit board Cb. By placing the circuit board Cb on the measurement table 91, it is easy to connect to the terminals on the back surface of the board. When measuring voltage as an electrical characteristic, for example, one point on the circuit board Cb can be connected to ground and another point can be brought into contact with the probe P to measure the voltage. Note that the test apparatus 9 does not have a measurement table 91, and the circuit board Cb may be placed directly on the mounting table.

[0030] The horizontal direction moving means 93 has an X-axis direction moving means Mx that moves the measuring means 92 in the X-axis direction, and a Y-axis direction moving means My that moves it in the Y-axis direction. The measuring means 92 is provided on a beam portion B of the X-axis direction moving means Mx, and the beam portion B is connected to the Y-axis direction moving means My. This allows the X-axis direction moving means Mx equipped with the measuring means 92 to be moved in the Y-axis direction by the Y-axis direction moving means My.

[0031] The measuring means 92 has a probe support part Sp that supports the probe P so that it can be displaced upward, and an elevation means 92a (Z-axis direction moving means Mz) that moves the probe support part Sp in the height direction above the circuit board Cb. In FIG. 2, the probe support part Sp is a plate-like member with a through hole opened in the vertical direction. The probe P is inserted into the through hole of the probe support part Sp so that its tip part of a predetermined length protrudes below the probe support part Sp. The outer diameter (maximum diameter) of the probe P is preferably larger than the inner diameter of the through hole so that the probe P does not fall through the through hole. Note that the probe support part Sp is not limited to a plate-like member as long as it can support the probe P so that it can be displaced upward. The probe support part Sp may also support the probe P in a fixed manner.

[0032] Each of the moving means Mx, My, and Mz has a motor, and the rotational force output from the motor is transmitted to a ball screw or belt, causing the measuring means 92 to move on the device main body 90. By controlling the movement of the moving means Mx, My, and Mz using a program, the probe P can be freely moved horizontally and vertically relative to the circuit board Cb. This allows the probe P to be brought into contact with any position on the circuit board Cb, and the electrical characteristics can be measured automatically.

[0033] It is preferable that the measuring means 92 further includes an imaging means capable of imaging the circuit board. In this case, if the circuit board is first placed in the test device 9, the process from image acquisition to measurement can be carried out continuously, and the time and effort required to acquire image information in advance and correct for tilt, etc. can be eliminated, resulting in particularly excellent workability.

[0034] (First embodiment) An electrical characteristic measurement method using the electrical characteristic measurement system of the present invention will be described with reference to FIG. 3. FIG. 3 is a flowchart showing an example of the flow of the electrical characteristic measurement method according to the first embodiment of the present invention. The measurement method according to the first embodiment shown in FIG. 3 includes an image information acquisition step S1, a substrate placement step S2, a measurement position registration step S3, a program generation step S4, and a measurement execution step S5. It is sufficient that the electrical characteristic measurement method of the present invention includes at least the image information acquisition step S1 and the measurement position registration step S3.

[0035] (Image information acquisition step S1) In the image information acquisition step S1, image information of a circuit board viewed from above is acquired. The image information of the circuit board can be acquired using, for example, an imaging means such as a camera. When imaging the circuit board with a camera, it is preferable to image the circuit board together with a ruler or other length reference. This allows the scale to be set (image size registration) in the measurement position registration step described below, enabling more accurate measurements.

[0036] (Board installation process S2) In the board placement step S2, the circuit board is placed on a measurement table. The circuit board is preferably fixed to the measurement table so that its length and width directions coincide with the X and Y directions of the test equipment.

[0037] (Measurement position registration process S3) In the measurement position registration step S3, the user uses an information processing device to register measurement position information, which is information about measurement positions on the circuit board. The user first displays the image information acquired in the image information acquisition step S1 as a photograph on a display unit (screen). The measurement position information is registered by using a pointing device or the like to select a measurement position on the display unit displaying the image information of the circuit board.

[0038] The measurement position registration step S3 will be described in detail with reference to Fig. 4 to Fig. 6. Fig. 4 is a diagram showing the circuit board before and after correction, Fig. 5 is a diagram showing an example of a screen for setting a scale, and Fig. 6 is a diagram showing an example of a screen for registering measurement positions.

[0039] If the displayed photograph is tilted or distorted, it is preferable to correct it. For example, to correct the tilt, a user can use a pointing device or other device to select the four corners of the circuit board on the screen and perform correction processing to eliminate tilt in the X-axis and Y-axis directions. As shown in Figure 4, by encircling the outer edge of the circuit board in the slightly tilted image on the left (before correction), the image on the right (after correction) is corrected. If the image information is acquired in advance before the circuit board is placed on the measurement table of the test equipment and the electrical characteristic measurement system has the function of correcting the tilt of the image information of the circuit board when registering the measurement position information, the probe can be more accurately brought into contact with the measurement position, resulting in more accurate measurement of the electrical characteristics.

[0040] In this process, the scale of the photograph can also be set. The scale can be set, for example, by inputting the actual length per pixel of the photograph, or by selecting any two points on the ruler and inputting the length between those two points if photographs are also taken of a ruler (see Figure 5). It is preferable to set the scale separately for both the X-axis and Y-axis directions of the circuit board.

[0041] The user registers measurement position information by using a pointing device or the like to select a measurement position on the display of the electrical characteristics measurement system, which displays image information of the circuit board (see Figure 6). Prior to registering the measurement position information, the user selects, for example, a corner (the upper left corner in Figure 6) as the starting point (origin) where the probe will be positioned at the beginning of the measurement. Next, any number of measurement positions are selected and the measurement position information is registered.

[0042] (Program generation process S4) In the program generation step S4, a program (measurement execution code) is generated based on the information registered in the measurement position registration step S3. In this step, the expected measurement time can be calculated and the probe movement sequence can be confirmed. In addition, the test equipment can be operated to check the actual movement of the measurement means.

[0043] (Measurement execution step S5) In the measurement execution process S5, the electrical characteristics of the circuit board are measured according to the program generated in the program generation process S4. In this process, you can also adjust externally connected devices prior to the measurement. Specifically, you can perform connection tests and settings for the Grbl controller, serial connection, and GPIB connection.

[0044] The measurement results acquired in the measurement execution step S5 will now be described. FIG. 7 is a diagram showing an example of a measurement screen displayed on the display unit of the information processing device. As shown in FIG. 7, electrical characteristics such as voltage, current, active power, and apparent power can be measured. In addition, values such as reactive power, power factor, phase angle, voltage frequency, current frequency, electric energy, positive electric energy, and negative electric energy can also be measured. These measurement items can be freely selected to obtain measured values for required items. Measurement can be performed either manually or automatically. During automatic measurement, data can be acquired multiple times at set intervals (sampling intervals) within a set measurement time.

[0045] (Second embodiment) An electrical characteristic measuring method according to a second embodiment of the present invention will be described with reference to FIG. 8 . FIG. 8 is a flowchart showing an example of the flow of the electrical characteristic measuring method according to the second embodiment of the present invention. The measuring method according to the second embodiment shown in FIG. 8 includes a board installation step S11, an image information acquisition step S12, a measurement position registration step S13, a program generation step S14, and a measurement execution step S15. The measuring method according to the second embodiment differs from the first embodiment in that the board installation step S11 precedes the image information acquisition step S12. As a result, in the second embodiment, the image information acquired in the image information acquisition step S12 is image information of the circuit board in a state where it is installed on the measurement table. Therefore, it is not necessary to acquire image information at a separate location before installing the circuit board on the measurement table. As a result, once the circuit board is installed in the test equipment, measurement can be performed directly, improving workability during measurement.

[0046] When measuring electrical characteristics using this method, it is preferable that the measuring means has an imaging means for imaging the circuit board. In this case, it is possible to directly register the measurement position in real time while viewing an image of the circuit board on the measurement table on the display unit, which eliminates the need for scale setting, tilt correction, etc., resulting in superior operability.

[0047] Although the electrical characteristic measuring system and the electrical characteristic measuring method of the present invention have been described above, the present invention is not limited to the above-described embodiments. [Industrial Applicability]

[0048] The electrical characteristic measuring method of the present invention allows for easy registration of measurement position information and is highly operable, making it a useful tool for evaluating the electrical characteristics of circuit boards. [Explanation of symbols]

[0049] 1. Electrical characteristics measurement system 2. Information processing equipment 3. Image acquisition unit 4 Display 5 Input section 6 Database 7 Output section 8 Storage area 9 Test Equipment 90 Device body 91 Measuring table 92 Measurement means 92a Lifting means 93 Horizontal movement means B beam part Cb circuit board Mx X-axis direction movement means My Y-axis movement means Mz Z-axis direction movement means P probe Sp probe support

Claims

1. An electrical characteristic measurement system for measuring electrical characteristics of a circuit board, comprising: the system includes an information processing device that registers measurement position information that is information about measurement positions on the circuit board, and a test device that measures electrical characteristics of the circuit board based on the measurement position information registered by the information processing device; the test apparatus comprises a measurement table on which the circuit board can be placed, and measurement means having a probe that is movable horizontally relative to the circuit board placed on the measurement table and that comes into contact with a measurement position on the circuit board to measure electrical characteristics; The information processing device has a display unit and a function of registering the measurement position information by selecting a measurement position on the display unit that displays image information of the circuit board.

2. the image information of the circuit board is information acquired in advance before the circuit board is placed on the measurement table; 2. The electrical characteristic measuring system according to claim 1, further comprising a function for correcting the inclination of the image information of the circuit board when the measurement position information is registered.

3. 3. The electrical characteristic measurement system according to claim 1, wherein the measurement means comprises a probe support portion that supports the probe so that the probe can be displaced upward, and a lifting means that moves the probe support portion in the height direction above the circuit board.

4. 2. The electrical characteristic measuring system according to claim 1, wherein the image information of the circuit board is information acquired after the circuit board is placed on the measuring table.

5. An electrical characteristic measuring method using an electrical characteristic measuring system for measuring electrical characteristics of a circuit board, comprising: The electrical characteristic measuring method includes: an image information acquisition step of acquiring image information of the circuit board; a measurement position registration step of registering measurement position information that is information about measurement positions on the circuit board; Equipped with an electrical characteristic measuring method characterized in that, in the measurement position registration step, the measurement position information is registered by selecting a measurement position on a display unit of the electrical characteristic measuring system that displays image information of the circuit board.

6. a board installation step of installing the circuit board on a measurement table before the image information acquisition step; 6. The electrical characteristic measuring method according to claim 5, wherein the image information acquired in the image information acquiring step is image information of the circuit board placed on the measurement table.

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