JP5494366B2 - Connector pin bending detection device - Google Patents

Description

  The present case relates to a connector pin bending detection device.

  When a press-fit assembly operation of a connector to a printed circuit board is performed, if a press-fit assembly connector (press-fit connector) is misfitted, repair may be difficult, and a great deal of damage may be caused. In particular, a press-fit connector requires a large force when a pin is press-fitted into a through-hole, so even if it is inserted while detecting the pressing force, it is assumed that there is an abnormality immediately before the printed circuit board is damaged. It is difficult to interrupt.

  Such a press-fitting mistake occurs due to the fact that the tip of the pin cannot be inserted into the through hole of the printed circuit board due to the bent pin of the connector. That is, if there is a pin bent, even if the connector is handled accurately using a robot, a press-fitting mistake cannot be prevented. For this reason, a connector with a bent pin needs to be detected and eliminated before press-fit assembly work.

  In recent years, in the detection of pin bending, a method has been adopted in which an image of a connector is captured using a camera, and whether or not the pin interval obtained from the image is within a reference range (for example, Patent Document 1). reference). However, with this method, the angle of the connector with respect to the line sensor camera varies, and the captured image may be distorted. For this reason, there is a possibility that pin bending cannot be detected with high accuracy. For this reason, recently, a method using a calibration master (hereinafter referred to as “master”) having the same structure as the connector has also been proposed. In this method, the master is manufactured in advance, the master pin image is taken under the same conditions as when pin bending is detected, and the pin interval of the master is compared with the pin interval acquired when pin bending is detected. It detects pin bending. However, as the number of types of connectors increases, it is necessary to manufacture as many masters as the number of connectors. Therefore, a large amount of cost is required to manufacture a large number of highly accurate masters.

  As a method that does not use the master, the pin arrangement of the connector is in a regular matrix, so that a row / column straight line approximation is performed from the pin arrangement, and a pin having a large deviation from the approximate straight line is used. There is a method to judge that it is bent. In this method, even when the pin arrangement is vertically long and the number of pins in the horizontal direction is small, an approximate straight line cannot be determined, or even when the pins are staggered, the pin bending is caused by the variation in the vertical pin spacing. Can be determined.

JP-A-3-276007

  By the way, recently, in order to shorten the time required for the press-fitting and assembling work of the connector, a technique for detecting the bending of the pin in parallel with the conveyance of the connector has been studied. In this case, if it is attempted to shorten the conveyance path as much as possible for the purpose of downsizing the apparatus used for press-fitting assembly, it is difficult to maintain the conveyance speed at a constant speed while photographing the connector being conveyed. That is, it is necessary to accelerate or decelerate the connector while detecting pin bending. When there is such acceleration / deceleration, the captured image expands and contracts in the transport direction, so the pin interval obtained from the captured image changes in the transport direction compared to the actual pin interval, and acquisition of the pin interval is difficult. There is a possibility that it cannot be performed with high accuracy.

  In order to solve this, a method of reducing the influence of the speed change by using the encoder signal of the motor constituting the transport device as the clock of the line sensor camera is also conceivable. However, even if the encoder signal is used as a clock, the encoder signal may contain a transmission system error, and there is a possibility that highly accurate detection cannot be performed.

  Accordingly, the present invention has been made in view of the above-described problems, and an object thereof is to provide a connector pin bending detection device capable of detecting pin bending with high accuracy.

  The pin bending detection device for a connector described in the present specification moves, in the uniaxial direction, a connector provided with a holding surface for holding a pin array having a plurality of pins arranged at predetermined intervals along the uniaxial direction. A position having an imaging region extending in the other axis direction intersecting the one axis direction within a plane in which the connector moves, and facing the holding surface while the connector is moved by the moving unit The line sensor camera that picks up the image of the pin array from the line sensor camera, and the interval in the uniaxial direction of the pin obtained from the imaging result by the line sensor camera is acquired as the imaging pin interval, and the uniaxial direction of the imaging pin interval Based on the approximate curve calculation unit for calculating the pin interval approximate curve, the imaging pin interval, and the pin interval approximate curve. And a, a determination unit bending of.

  The pin bending detection device for a connector described in the present specification has an effect that pin bending can be detected with high accuracy.

It is a figure which shows schematically the structure of the pin bending detection apparatus which concerns on one Embodiment. FIG. 2A is a view showing a holding surface of the connector, and FIG. 2B is a view showing a through hole of the printed board. It is a figure which shows a pin image. FIG. 4A is a diagram illustrating a control device of the pin bending detection device, and FIG. 4B is a diagram illustrating a hardware configuration of the control device. It is a flowchart which shows the process of a pin bending detection apparatus. It is a figure for demonstrating step S18, S20. It is a figure for demonstrating step S22-S26. FIG. 8A is an enlarged view of the range A in FIG. 7, and FIG. 8B is a diagram for explaining step S28. It is a figure which expands and shows the range B of FIG. It is the figure which showed Py (i, j) as a y-coordinate value (unit: pix) and the vertical axis | shaft as a y direction pin space | interval. It is a figure for demonstrating step S34. It is a graph showing four cubic approximate curves. It is a figure which shows the cubic approximation curve (reference | standard approximation curve) fy and the line distance average value (pix) avgPy. It is a figure for demonstrating step S42.

  Hereinafter, an embodiment of a pin bend detection device will be described in detail with reference to FIGS.

  FIG. 1 schematically shows a pin bend detection device 100 according to an embodiment. The pin bend detection device 100 is a device that detects a bend of the pin 32 while the connector 30 (here, a press-fit connector) is conveyed above the printed circuit board 20. As shown in FIG. 1, the pin bending detection device 100 includes a conveyance / press-in device 10 as a moving unit, an illumination device 18, and a line sensor camera 16.

  The conveying / pressing device 10 is a device that conveys the connector 30 in the y-axis direction as a uniaxial direction. As shown in FIG. 1, the conveyance / press-fitting device 10 includes a guide 12 extending in the y-axis direction, a hand 14 that can move in the y-axis direction along the guide 12, and can also move in the vertical direction in FIG. 1. Have. The hand 14 can hold the connector 30 and moves in the held state. Further, the hand 14 can press-fit the connector 30 into the printed circuit board 20 by moving downward in FIG. 1 with the connector 30 positioned above the printed circuit board 20.

  Here, the connector 30 will be described. FIG. 2A shows a state where the connector 30 is viewed from the holding surface 34 side of the pin 32. As shown in FIG. 2A, the connector 30 has a plurality (four rows) of pin rows each having a plurality of pins 32 arranged at predetermined intervals along the y-axis direction on the holding surface 34. . The plurality of pin rows are arranged along the x-axis direction as the other axis direction. In addition, as shown to Fig.2 (a), in a some pin row, each pin is a staggered arrangement | positioning. The arrangement of the pins 32 of the connector 30 is the same as the arrangement of a large number of through holes 22 provided in the printed board 20 shown in FIG. For this reason, when a downward force is applied to the connector 30 from the transport / press-fitting device 10 in a state where the positional relationship between the pins 32 and the through-holes 22 is the same, each pin 32 is press-fitted into the corresponding through-hole 22. . Thereby, the connector 30 is assembled to the printed circuit board 20.

  Returning to FIG. 1, the illumination device 18 irradiates the tip of the pin 32 with light. The line sensor camera 16 has an imaging region extending in the x-axis direction, and images the pin 32 irradiated with light by the illumination device 18 while the transport / press-fitting device 10 transports the connector 30. , An image (hereinafter referred to as “pin image”) is acquired.

  FIG. 3 shows an example of a pin image acquired by the line sensor camera 16. As described above, when the pin image is acquired, the tip of the pin is illuminated by the illuminating device 18. Therefore, in the pin image of FIG. 3, the portion where the pin 32 exists is displayed in white, and the other portion is displayed. It is displayed in black.

  FIG. 4A is a block diagram illustrating a control system of the pin bend detection device 100. As shown in FIG. 4A, in the present embodiment, the pin bend detection device 100 includes a control device 50. The control device 50 performs overall processing of each component of the pin bend detection device 100 and performs data processing.

  FIG. 4B shows the hardware configuration of the control device 50. As shown in FIG. 4B, the control device 50 is an information processing device such as a PC, and includes a CPU 90, a ROM 92, a RAM 94, a storage unit (HDD (Hard Disk Drive)) 96, an input / output unit 97, and the like. I have. Each component of the control device 50 is connected to the bus 98. In the control device 50, the CPU 90 executes the program stored in the ROM 92 or the HDD 96, thereby realizing the function shown in FIG.

  FIG. 4C shows a functional block diagram of the control device 50. As illustrated in FIG. 4C, the control device 50 functions as a control unit 52, an approximate line calculation unit 54, an approximate curve calculation unit 56, and a determination unit 58. The control unit 52 controls operations of the transport / press-fitting device 10, the lighting device 18, and the line sensor camera 16. The approximate line calculation unit 54, the approximate curve calculation unit 56, and the determination unit 58 execute a pin bending detection process described later.

  Next, pin bending detection processing by the pin bending detection device 100 of the present embodiment will be described in detail along the flowchart of FIG. 5 with reference to other drawings as appropriate.

  As a premise of the processing of FIG. 5, it is assumed that the connector 30 is not gripped by the hand 14 of the transport / press-fitting device 10 and imaging by the line sensor camera 16 is not started. In step S <b> 10 of FIG. 5, the control unit 52 controls the transport / press-fitting device 10 to cause the hand 14 to grip the connector. Next, in step S12, the control unit 52 controls the transport / press-fitting device 10 to start transporting the connector 30 (transport in the -y direction in FIG. 1). In the conveyance of the connector 30, acceleration to a predetermined speed, constant speed movement, and speed become zero until the connector press-fitting start position above the printed circuit board 20 is reached from the position where the connector is gripped. Decelerate.

  Next, in step S <b> 14, the control unit 52 determines whether it is the timing when the connector 30 has moved above the line sensor camera 16. In this case, the control unit 52 makes a determination based on the elapsed time after performing the process of step S12. If the determination here is negative, the system waits until the timing comes. Then, when the determination in step S14 is affirmed, the process proceeds to step S16. In the present embodiment, it is assumed that the timing comes while the connector 30 is accelerating.

  If transfering it to step S16, the control part 52 will control the line sensor camera 16, and will image a pin image. It is assumed that the pin image is captured while the connector 30 is accelerating, during constant speed movement, and during deceleration. Next, in step S18, the approximate straight line calculation unit 54 (or approximate curve calculation unit 56) acquires the pin barycentric coordinates (xy coordinates) from the pin image. In this case, the approximate straight line calculation unit 54 (or the approximate curve calculation unit 56) acquires the pin center-of-gravity coordinates from the smaller y coordinate as shown in the left column of FIG.

  Next, in step S20, the approximate line calculation unit 54 (or approximate curve calculation unit 56) distributes the pin barycentric coordinates (xy coordinates) to the rows and columns. Specifically, as shown in the right column of FIG. 6, pin barycentric coordinates are distributed to rows and columns. Thereafter, the process proceeds to step S22.

  In step S22 to step S30, processing for detecting a bending of the pin in the x direction is executed.

In step S22, the approximate line calculator 54 generates an x approximate line (pin position approximate line) fx (j) for each column. For example, in the case of j = 1, the approximate straight line calculation unit 54 determines the pin barycentric coordinates (hereinafter, simply “pin coordinates”) of the pins belonging to the column 1 out of the obtained pin positions as shown in FIG. X approximate straight line fx (1) is calculated by the least square method or the like. Here, the x approximate line fx (1) can be expressed as the following equation (1), where a ₀ (1) and a ₁ (1) are constants and y (i, 1) is a variable.
fx (1) = a ₀ (1) + a ₁ (1) × y (i, 1) (1)

Similarly, the approximate straight line calculation unit 54 calculates the x approximate straight lines fx (2) to fx (4) using the pin coordinates of the pins belonging to the columns 2 to 4. In this case, the x approximate lines fx (2) to fx (4) can be expressed as the following expressions (2) to (4). Here, a ₀ (j) and a ₁ (j) are constants, and y (i, j) is a variable (j = 2 to 4).
fx (2) = a ₀ (2) + a ₁ (2) × y (i, 2) (2)
fx (3) = a ₀ (3) + a ₁ (3) × y (i, 3) (3)
fx (4) = a ₀ (4) + a ₁ (4) × y (i, 4) (4)

Next, in step S24, the approximate straight line calculation unit 54 calculates the average (unit: pix) of the distance between columns using the x coordinate approximate value. Specifically, the approximate line calculation unit 54 obtains a plurality of x coordinate approximate values of each column from the above formulas (1) to (4), and averages avgx (1) to avgx of the plurality of x coordinate approximate values. (4) is obtained (see FIG. 7). Then, the approximate straight line calculation unit 54 uses avgx (1) to avgx (4) to calculate the x-direction pin intervals Px (1) to Px (3) (see FIG. 7) by the following formulas (5) to (7). Calculate based on
Px (1) = avgx (2) −avgx (1) (5)
Px (2) = avgx (3) −avgx (2) (6)
Px (3) = avgx (4) −avgx (3) (7)

Next, in step S26, the approximate straight line calculation unit 54 calculates a dimension (unit: mm) per pixel in the x direction. Specifically, the approximate line calculation unit 54 obtains an average value (x direction pin interval value avgPx) of Px (1) to Px (3). The approximate straight line calculation unit 54 uses the x-direction pin interval value (avgPx (unit: pix)) and the pin interval design value (desPx (unit: mm)) acquired in advance at the design stage to From (8), the dimension resx (unit: mm / pix) per pixel in the x direction is obtained.
resx = desPx / avgPx (8)

Next, in step S28, the determination unit 58 determines that pin coordinates (x coordinates) having a large difference from the x approximate straight line are abnormal. Here, FIG. 8A is an enlarged view of the range A in FIG. 7, but the determination unit 58 first uses the resx obtained in step S <b> 26 to perform the vertical process in FIG. 8A. The unit (pix) of the axis is converted into a dimension (mm) as shown in FIG. The determination unit 58 then determines the amount of deviation (degree of divergence) between the pin coordinate (x coordinate) x (i, j) of the i-th row and j-th column and the x-line approximate value Appx (i, j) of the i-th row and j-th column. ) Dx (i, j) is calculated using the following equation (9). Note that the x-line approximate value Appx (i, j) can be obtained by substituting the y-coordinate value of the pin coordinate of the i-th row and j-th column into the x-approximate straight line fx (j).
dx (i, j) = | Appx (i, j) −x (i, j) | (9)

  And the determination part 58 determines with it being abnormal (pin bending), when the deviation degree calculated | required from the said Formula (9) exceeds the predetermined threshold value (for example, set to 0.1 mm). The threshold value can be determined based on, for example, the outer diameter of the pin 32 and the inner diameter of the through hole 22 provided in the printed board 20. In this case, the difference between the inner diameter of the through hole 22 and the outer diameter of the pin 32 can be set as a threshold value. By doing in this way, the determination part 58 can detect the bending of the pin with a high possibility that the pin 32 is not inserted in the through hole 22 as an abnormality.

  Next, in step S30, the determination unit 58 determines whether there is an abnormality. If the determination here is negative, that is, if there is no abnormality, the process proceeds to step S32. However, if the determination is affirmative, that is, if there is an abnormality, the process proceeds to step S46.

  When the process proceeds to step S32, in the subsequent processes (the processes of steps S32 to S44), a process of detecting a bending of the pin in the y direction is executed.

  When the process proceeds to step S32, the approximate curve calculation unit 56 calculates the y-direction pin interval array (row interval array) Py (i, j) for each column. Note that Py (i, j) is a pin interval obtained from the imaged pin image, and is hereinafter also referred to as an “imaging pin interval”. FIG. 9 shows the range B of FIG. 7 in an enlarged manner. The approximate curve calculation unit 56 calculates Py (i, j) shown in FIG. 7 by subtracting two adjacent pin coordinates (y coordinates (y (i, j))). FIG. 10 shows the imaging pin interval Py (i, j) calculated in this way, with the horizontal axis indicating the y coordinate value (unit: pix) and the vertical axis indicating the y direction pin interval.

Next, in step S34, the approximate curve calculation unit 56 generates a cubic approximate curve (pin interval approximate curve) of the imaging pin interval for each column. Specifically, the approximate curve calculation unit 56 uses the least-squares method based on the imaging pin interval Py (i, 2) if it is column 2 as shown in FIG. Then, a pin interval approximate curve fy ′ (2) is obtained. In this case, the approximate curve calculation unit 56 sets the pin interval approximate curve fy ′ (1) of the following equation (10) for the column 1 and the pin interval approximate curve fy ′ (2) of the following equation (11) for the column 2. ) Can be obtained. In addition, the approximate curve calculation unit 56 represents the pin interval approximate curve fy ′ (3) of the following equation (12) for the column 3 and the pin interval approximate curve fy ′ represented by the following equation (13) for the column 4. (4) can be obtained. Note that b ₀ (j), b ₁ (j), b ₂ (j), and b ₃ (j) are constants, and y (i, j) is a variable.
fy ′ (1) = b ₀ (1) + b ₁ (1) · y (i, 1)
+ B ₂ (1) · y (i, 1) ² + b ₃ (1) · y (i, 1) ³ (10)
fy ′ (2) = b ₀ (2) + b ₁ (2) · y (i, 2)
+ B ₂ (2) · y (i, 2) ² + b ₃ (2) · y (i, 2) ³ (11)
fy ′ (3) = b ₀ (3) + b ₁ (3) · y (i, 3)
+ B ₂ (3) · y (i, 3) ² + b ₃ (3) · y (i, 3) ³ (12)
fy ′ (4) = b ₀ (4) + b ₁ (4) · y (i, 4)
+ B ₂ (4) · y (i, 4) ² + b ₃ (4) · y (i, 4) ³ (13)

  These pin interval approximate curves are represented in one figure as shown in FIG. In this embodiment, as can be seen from the speed curve shown in FIG. 12 together with the approximate pin-interval curve, the pin image is acquired during acceleration, constant speed movement, and deceleration, so it is acquired from the pin image. The pin spacing that is done varies depending on the speed of the connector. That is, the smaller the speed, the wider the pin interval acquired from the pin image, and the higher the speed, the narrower the pin interval acquired from the pin image.

Next, in step S36, the determination unit 58 performs an approximate calculation of each column pin interval approximate value again to generate a reference pin interval approximate curve. More specifically, the determination unit 58 substitutes the y coordinate value of the pin coordinate of the i-th row and j-th column into the above formulas (10) to (13), so that the approximate value AppPy ′ ( i, j). Next, the determination unit 58 uses a least square method based on all the obtained approximate values AppPy ′ (i, j), and a cubic approximate curve (reference pin interval approximate curve) fy (see FIG. 13). Ask for. The reference pin interval approximate curve fy can be expressed as the following equation (14). B _{0 to} b ₃ are constants.
fy = b ₀ + b ₁ · y (i, j) + b ₂ · y (i, j) ² + b ₃ · y (i, j) ³
... (14)

  Next, in step S38, the determination unit 58 calculates the inter-line distance average value AppPy (i, j) (unit: pix) using the reference pin interval approximate value. Specifically, the determination unit 58 substitutes each numerical value obtained by substituting the y coordinate value of the pin coordinate of the i-th row and j-th column into the above equation (14) as a reference pin interval approximate value AppPy (i, j). To do. Next, the determination unit 58 obtains an average value of the reference pin interval approximate values AppPy (i, j) and sets this as an average line distance avgPy (unit: pix, see FIG. 13).

Next, in step S40, the determination unit 58 calculates a dimension (unit: mm) per pixel in the y direction. Specifically, the determination unit 58 uses the line spacing average value avgPy (unit: pix) obtained in step S38 and the pin interval (y direction) design value desPy acquired in advance at the design stage, and From (15), the dimension resy (unit: mm / pix) per pixel in the y direction is calculated.
resy = desPy / avgPy (15)

Next, in step S42, the determination unit 58 determines that the pin interval value having a large difference from the reference pin interval approximate value AppPy (i, j) is abnormal. Specifically, the determination unit 58 generates a graph as shown in FIG. 14 from the graph of FIG. 13 by using resy calculated using the above equation (15). The determination unit 58 then determines the amount of deviation (deviation) dy () between the imaging pin interval Py (i, j) and the reference pin interval approximate value Appx (i, j) in the i-th row and j-th column converted to the unit mm. i, j) is calculated using the following equation (16).
dy (i, j) = | Appy (i, j) −Py (i, j) | (16)

  Further, the determination unit 58 determines that the pin coordinate (y coordinate) in which the divergence obtained from the above equation (16) exceeds a predetermined threshold (for example, 0.1 mm) is abnormal (pin bending). .

  Next, in step S44, the determination unit 58 determines whether there is an abnormality. If the determination here is negative, that is, if there is no abnormality, the connector 30 has no pin bend, so the entire process of FIG. On the other hand, if the determination in step S44 is affirmative, the process proceeds to step S46.

  In step S46, since there is an abnormality in the pin 32, the control unit 52 does not press-fit the connector currently gripped by the hand 14 into the printed circuit board 20, and connects the connector 30 via the transport / press-in device 10. Move to a position to eliminate. Then, by releasing the grip of the connector by the hand 14, it is possible to eliminate a connector having a bent pin. When the above process is completed, the entire process of FIG. When the hand 14 is holding the connector 30 when all the processes in FIG. 5 are completed, the control unit 52 controls the transport / press-fitting device 10 so that the connector 30 is attached to the printed circuit board 20. Press fit.

  Thereafter, the processing of FIG. 5 is executed every time an instruction to start conveyance and press-fitting of a new connector is issued from an operator or the like.

  As described above in detail, according to the present embodiment, while the connector 30 is being transported by the transport / press-fitting device 10, a pin image is captured using the line sensor camera 16, and the approximate curve calculation unit 56 Then, the pin interval approximate curve is calculated using the pin interval (y direction) obtained from the imaging result. Then, the determination unit 58 determines the bending of the pin based on the pin interval obtained from the imaging result and the pin interval approximate curve. Therefore, in this embodiment, even when the connector 30 is accelerated or decelerated while the pin image is being captured, the approximate curve obtained from the pin interval acquired during acceleration and deceleration, the pin interval, By determining the pin bending based on the above, it is possible to determine a large change in the pin interval (that is, whether or not the pin is bent in the y direction) without being affected by the acceleration / deceleration. This makes it possible to detect pin bending with high accuracy. Further, even if the connector is accelerated or decelerated, the detection of pin bending is not affected, so that the conveyance path of the connector 30 by the conveyance / press-fitting device 10 can be set short. This makes it possible to reduce the size of the device. In this embodiment, since an approximate curve is obtained for each connector 30, it is possible to detect pin bending with high accuracy without any problem even if the type of connector is changed.

  Further, according to the present embodiment, the approximate curve calculation unit 56 calculates the pin interval approximate curve fy ′ (j) for each column, and the determination unit 58 uses the approximate value of the pin interval obtained from each approximate curve, A reference pin interval approximate curve fy is calculated, and it is determined that there is a pin bend when the difference between the reference pin interval approximate curve fy and the pin interval acquired from the pin image is greater than a threshold value. In this case, since the reference pin interval approximate curve fy is calculated using the approximate value of the pin interval obtained from the pin interval approximate curve fy ′, the determination unit 58 uses the influence of pin bending as the reference pin interval approximate curve fy. A curve with almost no can be calculated. Further, since it is determined that there is a pin bend when the deviation dy (i, j) between the reference pin interval approximate curve fy and the pin interval acquired from the pin image is larger than the threshold, The presence or absence of bending can be determined.

  In this embodiment, since a cubic curve is calculated as the pin interval approximate curve fy ′ (j), even if acceleration and deceleration are different and movement at a constant speed is performed, A pin interval approximate curve can be calculated appropriately. Note that a cubic or higher order curve may be calculated as the pin interval approximate curve fy '(j). Even in this case, when the acceleration and deceleration are different and the movement at a constant speed is performed, the approximate pin interval curve can be calculated appropriately.

  In the present embodiment, the approximate straight line calculation unit 54 approximates the change in the position of the pin 32 in the x-axis direction with respect to the y-axis direction to calculate an x approximate straight line (pin position approximate straight line) fx (j), The determination unit 58 determines pin bending from the degree of deviation between the x approximate straight line fx (j) and the pin position obtained from the pin image. Thereby, in this embodiment, the bending of the pin in the x direction can be detected with high accuracy based on the x approximate straight line. Moreover, since the determination part 58 determines pin bending from the deviation degree of an x approximate straight line and a pin position, it can determine pin bending by simple calculation.

  In the above embodiment, the pin bend in the y direction is determined based on the degree of deviation of the pin interval in the y direction from the reference pin interval approximate curve fy, and the x approximate straight line ( The case where the pin bending in the x direction is determined based on the degree of deviation from the pin position approximate straight line) has been described. However, the present invention is not limited to this. For example, only the pin bending in the y direction may be determined by the same method as described above.

  In the above embodiment, the case where the size of one pixel is calculated based on the formula (8) or the formula (15) (step S26, step S40) has been described in order to define the threshold value by the size. It is not limited. For example, if the threshold value can be defined by the number of pixels, step S26 and step S40 may be omitted.

  In the above embodiment, the case where the connector 30 has a plurality of pin rows has been described. However, the present invention is not limited to this, and the pin row may be one row. In this case, the pin bending can be determined from the degree of deviation between the pin interval approximate curve fy 'and the pin interval obtained from the pin image.

  In the above-described embodiment, the pin interval approximate curve fy ′ (j) is obtained for each column, the reference pin interval approximate curve fy is further obtained, and pin bending is detected using the reference pin interval approximate curve fy. explained. However, the present invention is not limited to this, and pin bending may be detected from the degree of deviation between the pin interval approximate curve fy ′ (j) obtained for each column and the pin interval of the j column obtained from the pin image. Good.

  In the above embodiment, the case where the threshold value is determined based on the outer diameter of the pin 32 and the inner diameter of the through hole 22 has been described, but the present invention is not limited to this. For example, the threshold value may be determined based on other factors such as the conveyance accuracy of the conveyance / press-fitting device 10.

  In the above embodiment, the case where the connector accelerates and decelerates while the pin image is captured by the line sensor camera 16 has been described. However, the present invention is not limited to this, and when the connector transport path can be taken long, a pin image may be taken while the connector maintains a constant speed. Even in such a case, it is possible to detect pin bending with high accuracy by performing pin bending detection similar to the above embodiment.

  In the above-described embodiment, the case where the pin bending of the connector 30 is detected while the connector 30 is being transported to press-fit the printed circuit board 20 has been described. However, the present invention is not limited to this, and pin bending of the connector 30 may be detected while the connector 30 is moving under other circumstances.

  The above-described embodiment is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

10 Conveying and press-fitting device (moving part)
32 pin 30 connector 34 holding surface 56 approximate curve calculation unit 54 approximate straight line calculation unit 58 determination unit 100 pin bending detection device

Claims (6)

A connector provided with a holding surface for holding a pin row having a plurality of pins arranged at a predetermined interval along a uniaxial direction, a moving unit that moves in the uniaxial direction;
The pin array has an imaging region extending in the other axis direction intersecting the one axis direction within a plane in which the connector moves, and the pin array from a position facing the holding surface while the connector is moved by the moving unit A line sensor camera that captures
The interval between the pins in the uniaxial direction obtained from the imaging result of the line sensor camera is acquired as an imaging pin interval, and a change in the uniaxial direction of the imaging pin interval is approximated to calculate a pin interval approximate curve. An approximate curve calculation unit;
A pin bending detection device for a connector, comprising: a determination unit that determines the bending of the pin based on the imaging pin interval and the pin interval approximate curve.   2. The determination unit according to claim 1, wherein the determination unit determines that the pin is bent when a deviation degree of the imaging pin interval from the pin interval approximate curve is larger than a predetermined threshold. Pin-bending detection device for connectors. The holding surface of the connector is provided with a plurality of the pin rows,
The approximate curve calculation unit calculates the pin interval approximate curve for each pin row,
The determination unit calculates a reference pin interval approximate curve using an approximate value of the pin interval of each pin row obtained from each pin interval approximate curve, and calculates the reference pin interval approximate curve and the imaging pin interval. The connector pin bending detection device according to claim 1, wherein when the deviation degree is larger than a predetermined threshold, it is determined that the pin is bent.   4. The connector according to claim 2, wherein the threshold value is determined based on an outer diameter of the pin and an inner diameter of a through hole formed in a printed board into which the pin is inserted. Pin bending detection device.   5. The connector pin bending detection device according to claim 1, wherein the approximate curve calculation unit calculates a cubic or higher-order curve as the pin interval approximate curve. 6. The position of each pin included in the pin array obtained from the imaging result by the line sensor camera is acquired as the imaging pin position, and the change of the imaging pin position in the other axis direction is approximated. An approximate straight line calculation unit for calculating a pin position approximate straight line,
The connector according to claim 1, wherein the determination unit determines the bending of the pin based on a degree of deviation of the imaging pin position from the pin position approximate straight line. Pin bending detection device.

Images