PCB (Printed Circuit Board) surface defect detection equipment based on CIS (Contact Image Sensor)

Abstract

The invention discloses PCB surface defect detection equipment based on CIS, and belongs to the field of machine vision detection. According to the invention, the technical problem that the detection quality and the detection efficiency cannot be considered at the same time in the existing PCB surface defect detection mode is solved. The transmission assembly is installed at the upper end of the equipment frame assembly in the horizontal direction, the driving assembly, the detection assembly and the detection trigger assembly are all installed on the equipment frame assembly, the driving assembly is arranged on the lower side of the transmission assembly, the detection assembly is arranged in the middle of the upper side of the transmission assembly, and the detection trigger assembly is arranged on the front portion of the upper side of the transmission assembly. The detection triggering assembly comprises a photoelectric switch, the detection assembly comprises a CIS body, the signal output end of the photoelectric switch is connected with the CIS body, the PCB is arranged on the upper surface of the transmission assembly, the PCB sequentially passes through the lower side of the detection triggering assembly and the lower side of the detection assembly through the moving transmission assembly, and picture collection of the PCB is achieved through the CIS body. The detection quality and the detection efficiency are both considered, and the method is used for PCB surface defect detection.

Description

Technical Field

[0001] The invention relates to a CIS-based PCB surface defect detection device, belonging to the field of machine vision detection. 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 electrical connection of electronic components. With the changes in product demand and the development of technology, large-size PCBs provide more space for future upgrades and expansions. Large-size PCBs help reduce signal interference and noise, improve signal quality, carry more circuits and components, and provide stronger power transmission capabilities.

[0003] The existing method for detecting PCB surface defects is to use cameras and lenses for image acquisition. The purpose is to detect the printing condition of PCB boards and the accuracy of the fitting positions of various types of electronic components. When using ordinary industrial lenses, there are visual errors because the incident light and the imaging light are not designed to be parallel. The clarity of the middle and edge of the field of view is different, the edges are blurred, and the lens shoots from the middle to the surroundings. There are occlusion and shadow problems in uneven positions, which seriously affect the detection of PCB surface defects. Although the use of telecentric lenses solves the above problems of ordinary industrial lenses, due to the telecentric characteristics of telecentric lenses with parallel light, the field of view of the lens is limited by its own size. Large-size PCB detection requires the collection of multiple pictures, and the entire PCB detection needs to be spliced ​​with pictures. The detection time efficiency is low, the overall structure of the detection equipment is complex, and the cost is high.

[0004] In summary, the existing detection methods for PCB surface defects have the technical problem that the detection quality and detection efficiency cannot be taken into account at the same time. Summary of the invention

[0005] The present invention aims to solve the technical problem that the existing detection method for PCB surface defects cannot balance the detection quality and detection efficiency, and further provides a PCB surface defect detection device based on CIS.

[0006] The technical solution of the present invention is a CIS-based PCB surface defect detection device, comprising a device frame component, a drive component, a transmission component, a detection component and a detection trigger component, wherein the transmission component is mounted on the upper end of the device frame component in a horizontal direction, the drive component, the detection component and the detection trigger component are all mounted on the device frame component, the drive component is arranged on the lower side of the transmission component, the detection component is arranged on the middle part of the upper side of the transmission component, and the detection trigger component is arranged on the upper front part of the transmission component;

[0007] The detection trigger component includes a photoelectric switch, and the detection component includes a CIS body. The Chinese name of CIS (contact imaging sensor) is contact image sensor. The signal output end of the photoelectric switch is connected to the CIS body, the drive component is used to drive the transmission component, and the PCB is arranged on the upper surface of the transmission component. The PCB passes through the detection trigger component and the lower side of the detection component in turn through the moving transmission component, and the image of the PCB is collected through the CIS body.

[0008] As another improvement of the present invention, the equipment frame assembly comprises a profile frame, a foot, a detection platform and a baffle;

[0009] The bottom end of the profile frame is provided with a foot, the top surface of the profile frame is provided with a detection platform, and baffles are provided on both the left and right sides of the detection platform.

[0010] As another improvement of the present invention, the driving assembly includes a motor, a driving device and a photoelectric encoder. The driving device is installed on the aluminum profile on the lower side of the detection platform, the motor is fixed on the driving device, the output shaft of the motor is connected to the internal belt of the driving device, the photoelectric encoder is fixed on the outer casing of the driving device, the shaft end of the photoelectric encoder is connected to the output shaft of the motor through a coupling, and the signal output end of the photoelectric encoder is connected to the CIS body.

[0011] As another improvement of the present invention, the detection trigger assembly also includes a photoelectric bracket, which spans the detection platform. The photoelectric switch is fixed in the middle of the photoelectric bracket by bolts, and the emitting surface and the receiving surface of the photoelectric switch are both vertically downward.

[0012] As another improvement of the present invention, the profile frame includes multiple aluminum profiles, bolts and slider nuts. The multiple aluminum profiles are spliced ​​together by bolts and slider nuts, and right-angle fixings are provided at the connections between the multiple aluminum profiles.

[0013] As another improvement of the present invention, the transmission assembly includes a bearing seat, a transmission guide roller and a transmission belt. Bearing seats are arranged at the front and rear ends of the transmission assembly. Two groups of transmission guide rollers are respectively installed at the front and rear ends of the transmission assembly through the bearing seats, and the transmission belt is installed on the two groups of transmission guide rollers.

[0014] As another improvement of the present invention, a belt groove is provided on the transmission guide roller, and the transmission belt is installed on the two groups of transmission guide rollers through the belt groove.

[0015] As another improvement of the present invention, the detection component also includes a detection bracket, two groups of detection brackets are symmetrically installed on the detection platform, the CIS body is installed on the two groups of detection brackets, the installation direction of the CIS body is perpendicular to the movement direction of the PCB, and the detection surface of the CIS body is vertically downward.

[0016] As another improvement of the present invention, the width dimension of the detection platform is smaller than the length dimension of the CIS body in the installation direction.

[0017] Beneficial effects of the present invention:

[0018] 1. The present invention is a PCB surface defect detection device based on CIS, which adopts the parallel design of incident light and image light, and can effectively solve the visual error, the different clarity between the middle and the edge of the field of view, and the edge blur problem. The detection surface of the CIS body is set vertically downward to avoid the existence of occlusion and shadow phenomena in uneven positions. The detection device has only one relative movement relative to the PCB, which makes the movement of the entire mechanism simpler and the operation of the equipment more stable and efficient. It takes into account both the detection quality and detection efficiency of PCB surface defects.

[0019] 2. The detection width of the CIS body of the present invention fully meets the existing PCB width, and the detection can be completed through one scan, thereby improving the detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a CIS-based PCB surface defect detection device of the present invention;

[0021] Figure 2 It is a front view of a CIS-based PCB surface defect detection device of the present invention;

[0022] Figure 3 It is a schematic diagram of the framework components;

[0023] Figure 4 is a schematic diagram of the drive assembly;

[0024] Figure 5 It is a schematic diagram of the transmission assembly;

[0025] Figure 6 is a schematic diagram of the detection component;

[0026] Figure 7 is a schematic diagram of the detection trigger component; DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the examples of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. In the description of the present invention, it should be explained that the positional relationships indicated by the terms "upper", "lower", "left", "right", etc. are only based on the positional relationships of the orientations shown in the drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the referred components have specific orientations, are constructed and operated in specific orientations, and therefore cannot be understood as limitations on the present invention.

[0028] Specific implementation method 1: Combination Figures 1 to 7 The present embodiment is described. The present embodiment is a CIS-based PCB surface defect detection device, which includes a device frame component 1, a drive component 2, a transmission component 3, a detection component 4 and a detection trigger component 5. The transmission component 3 is mounted on the upper end of the device frame component 1 in a horizontal direction. The drive component 2, the detection component 4 and the detection trigger component 5 are all mounted on the device frame component 1. The drive component 2 is arranged on the lower side of the transmission component 3, the detection component 4 is arranged on the upper middle part of the transmission component 3, and the detection trigger component 5 is arranged on the upper front part of the transmission component 3.

[0029] The detection trigger component 5 includes a photoelectric switch 52, the detection component 4 includes a CIS body 42, the signal output end of the photoelectric switch 52 is connected to the CIS body 42, the driving component 2 is used to drive the transmission component 3, the PCB is arranged on the upper surface of the transmission component 3, the PCB passes through the detection trigger component 5 and the lower side of the detection component 4 in turn through the moving transmission component 3, and the image of the PCB is captured through the CIS body 42.

[0030] CIS body refers to CMOS image sensor. The PCB first passes through the lower side of the detection trigger component through the moving transmission component. The photoelectric switch triggers its driver after delay to output the photoelectric switch control signal to the CIS body. The PCB passes through the lower side of the detection component through the moving transmission component. The CIS body can accurately capture the picture of the entire PCB. After the CIS body captures the picture, it is transmitted to the computer through a professional image acquisition card for further processing.

[0031] The detection width of the CIS body is determined by its own length, and the detection accuracy will not decrease due to the increase in width. The integrated design of the CMOS sensor, light source and lens inside the CIS body has the characteristics of parallel light telecentricity, which makes the detection stability high, and the collected pictures are the characteristics of the target true restoration without distortion. The detection distance and detection surface are smaller than the traditional camera lens mode, making the installation space more compact.

[0032] The parallel design of incident light and imaging light can effectively solve the problems of visual error, different clarity between the middle and edge of the field of view, and blurred edges. The detection device has only one relative movement relative to the PCB, which makes the movement of the entire mechanism simpler and the operation of the equipment more stable and efficient. It takes into account both the detection quality and detection efficiency of PCB surface defects. In this embodiment, a CIS-based PCB surface defect detection device is mainly used to detect the printing condition of PCB boards and the accuracy of the fitting positions of various types of electronic components. After detection, defective products are promptly removed and repaired in time to improve the production qualification rate of PCB products and reduce production costs.

[0033] Specific implementation method 2: Combination Figures 1 to 7 To illustrate this embodiment, this embodiment differs from the first embodiment in that the equipment frame assembly 1 includes a profile frame 11, a foot 12, a detection platform 13 and a baffle 14;

[0034] The bottom end of the profile frame 11 is installed with a foot 12, the top surface of the profile frame 11 is installed with a detection platform 13, and baffles 14 are installed on the left and right sides of the detection platform 13. The entire profile frame is firmly assembled to ensure the stability of equipment operation, prevent displacement and deformation due to vibration, impact and external force, and maintain a stable working state. The adjustable foot at the bottom of the profile frame can be manually adjusted to keep the entire detection equipment horizontal and vertical when the equipment frame or the factory floor is not flat enough. The detection platform and baffle are fixed on the top of the profile. The detection of the entire PCB is completed on the detection platform, and the CIS body of the detection component moves relative to the PCB to collect images. The function of the side baffle of the detection platform is to prevent the PCB from running off and sliding out of the detection platform during transmission. Other components and connection methods are the same as those in the first specific implementation method.

[0035] Specific implementation method three: Combination Figures 1 to 7This embodiment is described. The difference between this embodiment and the specific embodiment 1 is that the drive assembly 2 includes a motor 21, a drive device 22 and a photoelectric encoder 23. The drive device 22 is installed on the aluminum profile on the lower side of the detection platform 13. The motor 21 is fixed on the drive device 22. The output shaft of the motor 21 is connected to the internal belt of the drive device 22. The photoelectric encoder 23 is fixed on the outer shell of the drive device 22. The shaft end of the photoelectric encoder 23 is connected to the output shaft of the motor 21 through a coupling. The signal output end of the photoelectric encoder 23 is connected to the CIS body 42. The drive device is fixed in the profile groove of the equipment frame assembly by bolts and slider nuts. The motor is fixed to the drive device by four sets of bolts. The motor provides rotational power as a power source to drive the internal belt of the drive device to move and then rotate the internal driving wheel of the drive device. The photoelectric encoder calculates the transmission speed by measuring the number of pulses per unit time, thereby realizing real-time monitoring and control of the transmission speed. The photoelectric encoder feeds back the motion signal to the CIS body, so that the speed of the CIS body collecting pictures is synchronized with the movement speed of the PCB, preventing the distortion of the collected pictures and ensuring the accuracy and stability of the detection process. Other components and connection methods are the same as those in the first or second embodiment.

[0036] Specific implementation method four: Combination Figures 1 to 7 This embodiment is described. The difference between this embodiment and the specific embodiment one is that the detection trigger component 5 also includes a photoelectric bracket 51. The photoelectric bracket 51 spans across the detection platform 13. The photoelectric switch 52 is fixed in the middle of the photoelectric bracket 51 by bolts. The emitting surface and the receiving surface of the photoelectric switch 52 are both vertically downward. The installation height is low, and it becomes more compact in space. The simple movement mode of the equipment and the compact space make it more coordinated with the upstream and downstream equipment to achieve more efficient and stable operation of the entire process and system. The other components and connection methods are the same as any one of the specific embodiments one to three.

[0037] Specific implementation method five: Combination Figures 1 to 7 This embodiment is described. The difference between this embodiment and the specific embodiment 1 is that the profile frame 11 includes multiple aluminum profiles, bolts and slider nuts. The multiple aluminum profiles are spliced ​​by bolts and slider nuts, and right-angle fixings are provided at the connection between the multiple aluminum profiles. The entire profile frame is firmly assembled to ensure the stability of equipment operation, prevent displacement and deformation due to vibration, impact and external force, and maintain a stable working state. The other components and connection methods are the same as any one of the specific embodiments 1 to 4.

[0038] Specific implementation method six: Combination Figures 1 to 7This embodiment is described. The difference between this embodiment and the specific embodiment one is that the transmission assembly 3 includes a bearing seat 31, a transmission guide roller 32 and a transmission belt 33. The front and rear ends of the transmission assembly 3 are arranged with bearing seats 31. Two sets of transmission guide rollers 32 are respectively installed on the front and rear ends of the transmission assembly 3 through the bearing seats 31, and the transmission belt 33 is installed on the two sets of transmission guide rollers 32. The bearing seat is fixed to the aluminum profile of the equipment frame assembly by bolts. A transmission guide roller is installed between the two bearing seats. The installation ensures horizontality and concentricity, and ensures centering and uniform force. After the transmission guide roller is installed, it rotates smoothly without obvious resistance and vibration. The other components and connection methods are the same as any one of the specific embodiments one to five.

[0039] Specific implementation method seven: Combination Figures 1 to 7 This embodiment is described. The difference between this embodiment and the first embodiment is that a belt groove is provided on the transmission guide roller 32, and the transmission belt 33 is installed on the two sets of transmission guide rollers 32 through the belt groove. The belt groove is provided on the transmission guide roller to prevent the transmission belt from rotating and deviating. The transmission belt is installed at the grooves of the two sets of transmission guide rollers. The tension of the transmission belt should be moderate. Too loose will cause slippage, and too tight will increase wear. The other components and connection methods are the same as any one of the first to sixth embodiments.

[0040] Specific implementation method eight: Combination Figures 1 to 7 This embodiment is described. The difference between this embodiment and the specific embodiment one is that the detection component 4 also includes a detection bracket 41. Two groups of detection brackets 41 are symmetrically installed on the detection platform 13. The CIS body 42 is installed on the two groups of detection brackets 41. The installation direction of the CIS body 42 is perpendicular to the movement direction of the PCB, and the detection surface of the CIS body 42 is vertically downward. The CIS body is straddled on the detection platform by two detection brackets. The installation direction of the CIS body is perpendicular to the movement direction of the PCB, and the installation height requires the same height on the left and right. The detection surface of the CIS body is set vertically downward to avoid obstruction and shadow phenomena in uneven positions. The detection equipment can be moved as a whole or the PCB can be moved to make the device have better compatibility. Other components and connection methods are the same as any one of the specific embodiments one to seven.

[0041] Specific implementation method nine: Combination Figures 1 to 7 This embodiment is described. The difference between this embodiment and the first embodiment is that the width of the detection platform 13 is smaller than the length of the installation direction of the CIS body 42. The length of the CIS body is larger than the width of the entire detection platform, ensuring the detection of the entire width of the PCB.

[0042] Combination Figures 1 to 7 The working principle of the present invention is described:

[0043] The PCB moves backward through the transmission belt on the transmission assembly, first passing through the lower side of the detection trigger assembly, and the photoelectric switch triggers its driver after delay to output the photoelectric switch control signal to the CIS body. When the PCB passes through the lower side of the detection assembly through the moving transmission assembly, the CIS body can accurately capture the image of the entire PCB. After the CIS body captures the image, it is transmitted to the computer through a professional image acquisition card for further processing.

[0044] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A CIS-based PCB surface defect detection device, characterized in that It comprises an equipment frame component (1), a driving component (2), a transmission component (3), a detection component (4) and a detection trigger component (5); the transmission component (3) is mounted on the upper end of the equipment frame component (1) in the horizontal direction; the driving component (2), the detection component (4) and the detection trigger component (5) are all mounted on the equipment frame component (1); the driving component (2) is arranged on the lower side of the transmission component (3); the detection component (4) is arranged on the middle part of the upper side of the transmission component (3); and the detection trigger component (5) is arranged on the front part of the upper side of the transmission component (3); The detection trigger component (5) comprises a photoelectric switch (52), the detection component (4) comprises a CIS body (42), the signal output end of the photoelectric switch (52) is connected to the CIS body (42), the drive component (2) is used to drive the transmission component (3), the PCB is arranged on the upper surface of the transmission component (3), the PCB passes through the detection trigger component (5) and the lower side of the detection component (4) in sequence through the moving transmission component (3), and the image of the PCB is collected through the CIS body (42).

2. A CIS-based PCB surface defect detection device according to claim 1, characterized in that The equipment frame assembly (1) comprises a profile frame (11), a base (12), a detection platform (13) and a baffle (14); A foot (12) is installed at the bottom end of the profile frame (11), a detection platform (13) is installed on the top surface of the profile frame (11), and baffles (14) are installed on the left and right sides of the detection platform (13).

3. The CIS-based PCB surface defect detection device according to claim 2, characterized in that: The driving assembly (2) comprises a motor (21), a driving device (22) and a photoelectric encoder (23). The driving device (22) is mounted on an aluminum profile on the lower side of the detection platform (13). The motor (21) is fixed on the driving device (22). The output shaft of the motor (21) is connected to an internal belt of the driving device (22). The photoelectric encoder (23) is fixed to a housing of the driving device (22). The shaft end of the photoelectric encoder (23) is connected to the output shaft of the motor (21) through a coupling. The signal output end of the photoelectric encoder (23) is connected to a CIS body (42).

4. The CIS-based PCB surface defect detection device according to claim 2, characterized in that: The detection trigger assembly (5) further comprises a photoelectric bracket (51), the photoelectric bracket (51) being arranged across the detection platform (13), the photoelectric switch (52) being fixed in the middle of the photoelectric bracket (51) by bolts, and the emitting surface and the receiving surface of the photoelectric switch (52) both being vertically downward.

5. The CIS-based PCB surface defect detection device according to claim 2, characterized in that: The profile frame (11) comprises a plurality of aluminum profiles, bolts and slider nuts. The plurality of aluminum profiles are spliced ​​together by bolts and slider nuts, and right-angle fixing pieces are arranged at the connection points between the plurality of aluminum profiles.

6. The CIS-based PCB surface defect detection device according to claim 1, characterized in that: The transmission assembly (3) comprises a bearing seat (31), a transmission guide roller (32) and a transmission belt (33). The bearing seats (31) are arranged at both the front and rear ends of the transmission assembly (3). Two sets of transmission guide rollers (32) are respectively installed at the front and rear ends of the transmission assembly (3) through the bearing seats (31). The transmission belt (33) is installed on the two sets of transmission guide rollers (32).

7. The CIS-based PCB surface defect detection device according to claim 6, characterized in that: The transmission guide roller (32) is provided with a belt groove, and the transmission belt (33) is installed on the two groups of transmission guide rollers (32) through the belt groove.

8. The CIS-based PCB surface defect detection device according to claim 1, characterized in that: The detection assembly (4) also includes detection brackets (41), two groups of detection brackets (41) are symmetrically installed on the detection platform (13), and the CIS body (42) is installed on the two groups of detection brackets (41). The installation direction of the CIS body (42) is perpendicular to the movement direction of the PCB, and the detection surface of the CIS body (42) is vertically downward.

9. The CIS-based PCB surface defect detection device according to claim 8, characterized in that: The width dimension of the detection platform (13) is smaller than the length dimension of the CIS body (42) in the installation direction.

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