A machine vision inspection device and method for PCB circuit solder joints

Abstract

The present invention relates to the field of PCB detection technology, and in particular to a machine vision inspection device and method for PCB circuit solder joints. Its technical solution includes: an adjustment seat and an adjustable base for adjusting the inclination of the adjustment seat, the adjustable base is provided with a housing; the adjustment seat is provided with a PCB positioning seat for positioning the PCB; and also includes an industrial visual camera, the housing drives the industrial visual camera to move through a lateral driving mechanism to inspect the PCB when the inclination is not adjusted and the PCB circuit solder joints after the inclination is adjusted. The present invention detects both the horizontal state and the inclined state of the PCB, and compares them with the multi-angle simulated image information of the pre-designed PCB circuit solder joints, thereby avoiding misjudging the PCB pass rate from only a vertical projection surface image of a horizontal PCB, and can not only determine whether the solder joint position is correct, but also determine whether the saturation of the solder joint is up to standard.

Description

Technical Field

[0001] The present invention relates to the technical field of PCB detection, and in particular to a machine vision inspection device and method for PCB circuit solder joints. Background Art

[0002] PCB (Printed Circuit Board), also known as printed circuit board in Chinese, is an important electronic component, a support for electronic components, and a carrier for the electrical connection of electronic components. Because it is made by electronic printing, it is called a "printed" circuit board.

[0003] The inspection of PCB circuit solder joints requires manual inspection of PCB board solder joints using visual inspection equipment to observe the solder joints on the PCB board and determine whether they are qualified.

[0004] After studying the prior art, the patent with the authorization announcement number CN214794527U discloses a PCB board solder joint visual inspection device based on AI technology. Specifically, it can pull the PCB board fixing device to move the No. 2 slider in the No. 2 slide groove, or rotate the connecting plate, and the steel ball in the circular groove on the No. 1 slider moves along the No. 1 slide groove, so that the solder joints at different positions on the upper surface of the PCB board can be observed;

[0005] In the above patents and prior art, PCB circuit solder joints are generally detected by detecting solder joints at different positions on a vertical projection plane. Even if the solder joint saturation is insufficient, the vertical projection plane is the same as the expected PCB circuit solder joint image, which will create the illusion that the PCB circuit solder joints are qualified. Summary of the invention

[0006] The purpose of the present invention is to address the problems existing in the background technology and to propose a machine vision inspection device and method for PCB circuit solder joints that can detect multiple vertical projection surfaces after the PCB angle is adjusted.

[0007] The technical solution of the present invention is a machine vision inspection device and method for PCB circuit solder joints, comprising:

[0008] An adjustment seat and an adjustable base for adjusting the inclination of the adjustment seat, wherein the adjustable base is provided with a housing;

[0009] The adjusting seat is provided with a PCB positioning seat for positioning the PCB;

[0010] It also includes an industrial vision camera. The housing drives the industrial vision camera to move through a lateral driving mechanism to inspect the solder joints of the PCB when the inclination angle is not adjusted and after the inclination angle is adjusted.

[0011] Preferably, the adjustable base comprises a base body, and a linear drive mechanism a, a linear drive mechanism b, a linear drive mechanism c and a linear drive mechanism d are arranged inside the base body;

[0012] The piston rods of the linear drive mechanism a, the linear drive mechanism b, the linear drive mechanism c and the linear drive mechanism d are all connected to the adjustment seat through an adjustment component;

[0013] The tilt angle of the adjustment seat is adjusted by adjusting the telescopic length of the piston rods of the linear drive mechanism a, the linear drive mechanism b, the linear drive mechanism c and the linear drive mechanism d;

[0014] The base body is also auxiliary-connected with the adjustment seat through an auxiliary connection assembly.

[0015] Preferably, the adjustment seat comprises a plate body, and a magnetic attraction member a is rotatably arranged in the middle of the edge line of the plate body;

[0016] The magnetic surfaces of the magnetic attraction members a are all provided with electric contacts a.

[0017] Preferably, the adjustment assembly includes an articulated seat fixed to the piston rod of the linear drive mechanism, a rotating shaft is rotatably mounted on the articulated seat, a magnetic attraction member b is fixed to the rotating shaft through a support rod, and an electric contact b is provided on the magnetic attraction surface of the magnetic attraction member b for contacting with the electric contact a to generate an electric signal;

[0018] The hinged seat is also provided with a driving motor for driving the rotating shaft to rotate.

[0019] Preferably, it also includes a central processing device, which receives the electrical signal generated by the contact between the electric contact a and the electric contact b and controls the working status of the linear drive mechanism a, the linear drive mechanism b, the linear drive mechanism c, the linear drive mechanism d, the lateral drive mechanism, the adjustment component and the industrial vision camera according to the electrical signal.

[0020] Preferably, the auxiliary connection assembly comprises a support rod fixed in the base body, and the free end of the support rod is connected to the telescopic rod through a universal joint;

[0021] The telescopic rod of the telescopic rod is rollingly connected to the bottom of the adjustment seat through a spherical joint.

[0022] Preferably, the central processing device is also connected to an external control terminal device wirelessly / wiredly;

[0023] The external control terminal device has the PCB pre-processing solder joint information and the circuit solder joint information after the PCB adjusts the inclination angle.

[0024] A machine vision inspection method for PCB circuit solder joints, using the above-mentioned machine vision inspection device for PCB circuit solder joints and obtaining PCB preprocessing information of an external control terminal device, specifically includes the following steps:

[0025] S100: Acquire multi-angle simulated image information of solder joints after PCB circuit soldering;

[0026] S200: acquiring a first image of a solder joint of a PCB circuit by using an industrial visual camera, and comparing the first image with a simulation image;

[0027] S300: After the PCB is rotated by a certain angle using the angle adjustment base, a second image of the solder joints of the circuits after the PCB is rotated is acquired using the industrial vision camera;

[0028] S400: comparing the second image with the simulated image of the solder joints of the PCB circuit after being rotated by a corresponding angle;

[0029] S500: Repeat the above steps S200-S400 as needed to determine whether the comparison result exceeds a preset threshold.

[0030] Preferably, in S500, when the comparison result exceeds a preset threshold, it is determined that the PCB circuit solder joint has a defect; when the comparison result does not exceed the preset threshold, it is determined that the PCB circuit solder joint is qualified.

[0031] Preferably, in said S100, the multi-angle simulated image information of the solder joints after soldering of the PCB circuit includes estimated PCB circuit solder joint image information, solder joint position information, solder joint saturation information and projection area information of the solder joints after PCB angle adjustment.

[0032] Compared with the prior art, the present invention has the following beneficial technical effects:

[0033] By detecting the horizontal and tilted states of the PCB and comparing them with the pre-designed multi-angle simulated image information of the PCB circuit solder joints, we can avoid misjudging the PCB pass rate from only a vertical projection surface image of a horizontal PCB. We can not only determine whether the solder joint position is correct, but also whether the saturation of the solder joint is up to standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the structure of a machine vision inspection device for PCB circuit solder joints in the present invention is provided;

[0035] Figure 2 It is a structural schematic diagram of an adjustable base in a machine vision inspection device for PCB circuit solder joints in the present invention;

[0036] Figure 3 It is a structural schematic diagram of the adjustment seat in the present invention;

[0037] Figure 4 It is a structural schematic diagram of the regulating component in the present invention;

[0038] Figure 5 It is a structural schematic diagram of the auxiliary connection component in the present invention;

[0039] Figure 6 It is a structural schematic diagram of the PCB in a horizontal state;

[0040] Figure 7 for Figure 6 Vertical projection view of the PCB;

[0041] Figure 8 It is a schematic diagram of the structure after the PCB is rotated 45° along the first direction;

[0042] Fig. 9 for Figure 8 Vertical projection view of the PCB;

[0043] Fig.10 It is a schematic diagram of the structure after the PCB is rotated 45° along the second direction;

[0044] Fig.11 for Fig.10 Vertical projection view of the PCB;

[0045] Fig.12 The present invention is a flowchart of the machine vision inspection device and method for PCB circuit solder joints.

[0046] Reference numerals: 100 housing;

[0047] 200 central processing equipment;

[0048] 300 adjustable base; 310 base body; 320 linear drive mechanism a; 330 linear drive mechanism b; 340 linear drive mechanism c; 350 linear drive mechanism d;

[0049] 400 adjustment seat; 410 plate body; 420 magnetic attraction member a; 430 electric contact a; 440 spherical interface;

[0050] 500 lateral drive mechanism;

[0051] 600 industrial vision cameras;

[0052] 700PCB positioning seat;

[0053] 800 auxiliary connecting assembly; 810 support rod; 820 universal joint; 830 telescopic rod; 840 ball joint;

[0054] 900 adjustment component; 910 hinge seat; 920 drive motor; 930 rotating shaft; 940 support rod; 950 magnetic attraction part b; 960 electric contact b;

[0055] 001PCB;002solder point. DETAILED DESCRIPTION

[0056] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0057] Embodiment 1

[0058] like Figure 1 As shown, the present invention proposes a machine vision inspection device for PCB circuit solder joints, comprising

[0059] An adjustment seat 400 and an adjustable base 300 for adjusting the inclination of the adjustment seat 400. A receiving groove for receiving the adjustment seat 400 is provided on the upper side of the adjustable base 300. When the PCB is vertically projected in a horizontal state, the adjustable base 300 and the adjustment seat 400 are at the same level.

[0060] The housing 100 is disposed on the adjustable base 300 ; the adjustable base 300 and the housing 100 constitute the main frame part of the inspection device.

[0061] The adjustment seat 400 is provided with a PCB positioning seat 700 for positioning the PCB; the PCB positioning seat 700 is provided with positioning pins for positioning the PCB; the PCB is located in the PCB positioning seat 700 in a horizontal state;

[0062] The industrial vision camera 600 is also included. The housing 100 drives the industrial vision camera 600 to move through the lateral driving mechanism 500 to inspect the solder joints of the PCB when the inclination angle is not adjusted and after the inclination angle is adjusted.

[0063] Reference Figure 2 The adjustable base 300 includes a base body 310, and a linear drive mechanism a320, a linear drive mechanism b330, a linear drive mechanism c340 and a linear drive mechanism d350 are arranged inside the base body 310; the position distribution direction thereof is a diamond distribution;

[0064] The piston rods of the linear drive mechanism a320, the linear drive mechanism b330, the linear drive mechanism c340 and the linear drive mechanism d350 are all connected to the adjustment seat 400 through the adjustment assembly 900; the connection method is a magnetic connection, which is described in detail below;

[0065] The tilt angle of the adjustment seat 400 is adjusted by adjusting the telescopic length of the piston rods of the linear drive mechanism a320, the linear drive mechanism b330, the linear drive mechanism c340 and the linear drive mechanism d350; when it is necessary to adjust the Figure 8 When the PCB is in the state shown, the linear drive mechanism a320 and the linear drive mechanism b330 work. Of course, when the piston rod of the linear drive mechanism a320 extends higher than the linear drive mechanism b330, the PCB can be moved as shown in FIG. Figure 8 The state shown is tilted;

[0066] Similarly, if you need to adjust the PCB to Fig.10 In the state shown, only the linear drive mechanism c340 and the linear drive mechanism d350 need to work;

[0067] The base body 310 is also auxiliary-connected with the adjustment base 400 through the auxiliary connection assembly 800. The auxiliary connection assembly 800 can prevent the adjustment base 400 from being completely separated from the adjustable base 300;

[0068] like Figure 3 As shown, the adjustment seat 400 includes a plate body 410, and a magnetic component a420 is rotatably arranged in the middle of the edge line of the plate body 410; a groove for the magnetic component a420 to swing is arranged on the plate body 410, and the direction of the groove is the same as the swing direction of the magnetic component a420; in addition, when the plate body 410 is tilted, due to the rotating setting of the magnetic component a420 and the action of its own gravity, it can maintain a vertical state.

[0069] The magnetic surfaces of the magnetic attraction members a420 are all provided with electrical contacts a430.

[0070] like Figure 4 As shown, the adjustment assembly 900 includes an articulated seat 910 fixed to the piston rod of the linear drive mechanism, a rotating shaft 930 is rotatably mounted on the articulated seat 910, a magnetic attraction member b950 is fixed to the rotating shaft 930 through a support rod 940, and an electric contact b960 is provided on the magnetic attraction surface of the magnetic attraction member b950 for contacting with the electric contact a430 to generate an electric signal;

[0071] A driving motor 920 for driving the rotating shaft 930 is also provided on the hinge seat 910. The driving motor 920 can adjust the vertical state of the support rod 940. When the magnetic attraction member a420 and the electric contact b960 are magnetically attracted, the corresponding linear driving mechanism can drive the plate body 410 to move.

[0072] It also includes a central processing device 200, which receives an electrical signal generated by the contact between the electrical contact a430 and the electrical contact b960 and controls the working states of the linear drive mechanism a320, the linear drive mechanism b330, the linear drive mechanism c340, the linear drive mechanism d350, the lateral drive mechanism 500, the adjustment component 900 and the industrial vision camera 600 according to the electrical signal. When the electrical contact a430 and the electrical contact b960 are in contact, an electrical signal is generated, and the central processing device 200 can judge the connection state between the corresponding linear drive mechanism and the corresponding magnetic attraction member a420 by the on-off of the electrical signal;

[0073] For example, when all the electrical contacts a430 and the electrical contacts b960 are in contact, it can be determined that the plate body 410 is in a horizontal state.

[0074] like Figure 5 As shown, the auxiliary connection assembly 800 includes a support rod 810 fixed in the base body 310, and the free end of the support rod 810 is connected to a telescopic rod 830 through a universal joint 820;

[0075] The telescopic rod 830 is connected to the bottom of the adjustment seat 400 in a rolling manner through the ball joint 840. Figure 3 as well as Figure 5 As shown, a spherical interface 440 is provided at the bottom of the plate body 410, and the top of the spherical joint 840 is spherical. The spherical top of the spherical joint 840 is arranged in the spherical interface 440 so that the angle of the plate body 410 can be freely adjusted, further improving the degree of freedom of the plate body 410.

[0076] The central processing device 200 is also connected to the external control terminal device wirelessly / wiredly;

[0077] The external control terminal device has the PCB pre-processing solder joint information and the circuit solder joint information after the PCB adjusts the inclination angle.

[0078] The working principle of the machine vision inspection device for PCB circuit solder joints based on the first embodiment is: PCB 001 is placed in the PCB positioning seat 700 and fixed, and the PCB is in a horizontal state, such as Figure 6 As shown, the industrial vision camera 600 is driven by the lateral driving mechanism 500 to detect the solder joints of the PCB 001 circuit in a horizontal state. The image obtained by the industrial vision camera 600 is as shown in FIG. Figure 7 As shown, Figure 7 A in the figure is an enlarged view of the solder joint, and it is compared with the expected PCB circuit solder joint simulation image for the first time. The first comparison can determine whether the solder joint position is correct;

[0079] Then, the linear drive mechanism a320 and the linear drive mechanism b330 work to adjust the adjustment seat 400 and the PCB positioning seat 700 to a certain angle; at this time, the longitudinal electric contact a430 is in the electric signal on state; the other two electric contacts a430 are in the off state; until PCB001 is in Figure 8 In the state shown, the industrial vision camera 600 is driven by the lateral driving mechanism 500 to detect the circuit solder joint 002 of the PCB 001 which is in the first direction tilt state. The image obtained by the industrial vision camera 600 is as shown in FIG. Fig. 9 As shown, Fig. 9 B is an enlarged view of the solder joint, and is compared with the simulated image of the solder joint of the PCB circuit after being rotated to a corresponding angle; this comparison can detect the saturation of solder joint 002;

[0080] Similarly, PCB001 can be adjusted to the following position by linear drive mechanism c340 and linear drive mechanism d350: Fig.10 In the state shown, the industrial vision camera 600 is driven by the lateral driving mechanism 500 to detect the circuit solder joint 002 of the PCB 001 in the second direction tilt state. The image obtained by the industrial vision camera 600 is as shown in FIG. Fig.11 As shown, Fig.11 C in the middle is an enlarged view of the solder joint, which is compared with the simulated image of the PCB circuit solder joint after being rotated to a corresponding angle; the saturation of solder joint 002 can be detected from another direction, thereby avoiding misjudging the qualified rate of PCB001 from only one vertical projection surface image of a horizontal PCB.

[0081] Embodiment 2

[0082] like Fig.12 As shown, the present invention also proposes a machine vision inspection method for PCB circuit solder joints, which utilizes the above-mentioned machine vision inspection device for PCB circuit solder joints and obtains PCB preprocessing information of an external control terminal device, specifically comprising the following steps:

[0083] S100: Acquire multi-angle simulated image information of solder joints after PCB circuit soldering;

[0084] In S100, the multi-angle simulated image information of the solder joints after the PCB circuit is soldered includes the estimated PCB circuit solder joint image information, solder joint position information, solder joint saturation information and the projection area information of the solder joints after the PCB angle is adjusted.

[0085] S200: acquiring a first image of a solder joint of a PCB circuit by using an industrial visual camera, and comparing the first image with a simulation image;

[0086] This comparison can determine whether the solder joints of the PCB circuit are correct.

[0087] S300: After the PCB is rotated by a certain angle using the angle adjustment base, a second image of the solder joints of the circuits after the PCB is rotated is acquired using the industrial vision camera;

[0088] S400: comparing the second image with the simulated image of the solder joints of the PCB circuit after being rotated by a corresponding angle;

[0089] This comparison can determine whether the saturation of the PCB circuit solder joints is qualified.

[0090] S500: Repeat the above steps S200-S400 as needed to determine whether the comparison result exceeds a preset threshold.

[0091] Since the angle adjustment range of the plate body 410 is relatively wide, the plate body 410 can be adjusted within the allowable angle adjustment range, so the solder joint detection operation can be repeated, further improving the accuracy of the solder joint detection.

[0092] In S500, when the comparison result exceeds the preset threshold, it is determined that the PCB circuit solder joint has a defect; when the comparison result does not exceed the preset threshold, it is determined that the PCB circuit solder joint is qualified.

[0093] The above-mentioned specific embodiments are only several preferred embodiments of the present invention. Based on the technical solutions of the present invention and the relevant inspirations of the above-mentioned embodiments, those skilled in the art can make various alternative improvements and combinations to the above-mentioned specific embodiments.

Claims

1. A machine vision inspection device for PCB circuit solder joints, characterized in that: include An adjustment seat (400) and an adjustable base (300) for adjusting the inclination angle of the adjustment seat (400), wherein the adjustable base (300) is provided with a housing (100); The adjustment seat (400) is provided with a PCB positioning seat (700) for positioning the PCB; It also includes an industrial visual camera (600), wherein the housing (100) drives the industrial visual camera (600) to move through a lateral driving mechanism (500) to inspect the solder joints of the PCB when the inclination angle is not adjusted and the solder joints of the PCB after the inclination angle is adjusted; The adjustable base (300) comprises a base body (310), and a linear drive mechanism a (320), a linear drive mechanism b (330), a linear drive mechanism c (340) and a linear drive mechanism d (350) are arranged inside the base body (310); The piston rods of the linear drive mechanism a (320), the linear drive mechanism b (330), the linear drive mechanism c (340) and the linear drive mechanism d (350) are all connected to the adjustment seat (400) via an adjustment assembly (900); The tilt angle of the adjustment seat (400) is adjusted by adjusting the telescopic lengths of the piston rods of the linear drive mechanism a (320), the linear drive mechanism b (330), the linear drive mechanism c (340) and the linear drive mechanism d (350); The adjustment seat (400) comprises a plate body (410), and a magnetic attraction member a (420) is rotatably arranged in the middle of the edge line of the plate body (410); The magnetic attraction surface of the magnetic attraction member a (420) is provided with an electric contact a (430); The base body (310) is also auxiliary-connected to the adjustment seat (400) via an auxiliary connection assembly (800); The adjustment assembly (900) comprises an articulated seat (910) fixed to a piston rod of a linear drive mechanism, a rotating shaft (930) being rotatably mounted on the articulated seat (910), a magnetic attraction member b (950) being fixed to the rotating shaft (930) via a support rod (940), and an electric contact b (960) for contacting an electric contact a (430) to generate an electric signal being disposed on a magnetic attraction surface of the magnetic attraction member b (950); The hinge seat (910) is also provided with a driving motor (920) for driving the rotating shaft (930) to rotate. The driving motor (920) adjusts the vertical state of the support rod (940). When the magnetic attraction member a (420) and the electric contact b (960) are magnetically attracted, the corresponding linear driving mechanism drives the plate body (410) to move. The invention also includes a central processing device (200), wherein the central processing device (200) receives an electrical signal generated by the contact between the electrical contact a (430) and the electrical contact b (960) and controls the working states of the linear drive mechanism a (320), the linear drive mechanism b (330), the linear drive mechanism c (340), the linear drive mechanism d (350), the lateral drive mechanism (500), the adjustment component (900) and the industrial vision camera (600) according to the electrical signal.

2. The machine vision inspection device for PCB circuit solder joints according to claim 1, characterized in that: The auxiliary connection assembly (800) comprises a support rod (810) fixed in the base body (310), and a free end of the support rod (810) is connected to a telescopic rod (830) via a universal joint (820); The telescopic rod (830) is rollingly connected to the bottom of the adjustment seat (400) via a spherical joint (840).

3. The machine vision inspection device for PCB circuit solder joints according to claim 1, characterized in that: The central processing device (200) is also connected to an external control terminal device wirelessly or by wire; The external control terminal device has the PCB pre-processing solder joint information and the circuit solder joint information after the PCB adjusts the inclination angle.

4. A machine vision inspection method for PCB circuit solder joints, characterized in that: Using the machine vision inspection device for PCB circuit solder joints as described in any one of claims 1 to 3, and obtaining PCB preprocessing information of an external control terminal device, specifically comprising the following steps; S100: Acquire multi-angle simulated image information of solder joints after PCB circuit soldering; S200: acquiring a first image of a solder joint of a PCB circuit by using an industrial visual camera, and comparing the first image with a simulation image; S300: After the PCB is rotated by a certain angle using the angle adjustment base, a second image of the solder joints of the circuits after the PCB is rotated is acquired using the industrial vision camera; S400: comparing the second image with the simulated image of the solder joints of the PCB circuit after being rotated by a corresponding angle; S500: Repeat the above steps S200-S400 as needed to determine whether the comparison result exceeds a preset threshold.

5. The machine vision inspection method for PCB circuit solder joints according to claim 4, characterized in that: In S500, when the comparison result exceeds the preset threshold, it is determined that the PCB circuit solder joint has a defect; when the comparison result does not exceed the preset threshold, it is determined that the PCB circuit solder joint is qualified.

6. The machine vision inspection method for PCB circuit solder joints according to claim 4, characterized in that: In the above S100, the multi-angle simulated image information of the solder joints after the PCB circuit is soldered includes the estimated PCB circuit solder joint image information, solder joint position information, solder joint saturation information and the projection area information of the solder joints after the PCB angle is adjusted.

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