High-precision high-frequency visual flying probe detection mechanism

Abstract

The invention discloses a high-precision and high-frequency visual flying probe detection mechanism in the technical field of circuit board detection. The high-precision and high-frequency visual flying probe detection mechanism comprises a rotating unit, a linear driving unit, a visual monitoring unit, a detection probe unit and a guide connecting unit, wherein the linear driving unit and the visual monitoring unit are arranged on the rotating unit; the detection probe unit is arranged at the output end of the linear driving unit; according to the visual monitoring unit, the light path layout is simplified through the prism piece, the space layout is saved, meanwhile, the adjusting piece is arranged so that the image acquisition equipment can be rapidly and manually adjusted, the operation convenience and the adjusting precision are both considered, the single focusing time is shortened, meanwhile, circuit boards with different thickness ranges can be detected in a matched mode, and the use range is widened.

Description

Technical Field

[0001] The present invention relates to the field of circuit board detection, and in particular to a high-precision and high-frequency visual flying probe detection mechanism. Background Art

[0002] In the production and testing of printed circuit boards (PCBs), flying probe testing covers many fields such as consumer electronics and automotive electronics. Flying probe testing is a key technology that uses moving probes to contact the solder joints and circuits of the circuit board to test the electrical performance. In existing technologies, some flying probe testing mechanisms generally have the following defects: Inconvenient visual system adjustment: The existing equipment's visual lens focal length adjustment is mostly fixed, which cannot quickly adapt to inspection scenarios of circuit boards of different thicknesses. Manual adjustment has low precision and cumbersome operation. Insufficient service life and stability: Most probes use a mechanical spring structure to connect the probe cantilever beam and the fixed bracket. Although this can offset the Z-axis gravity during flying probe testing, the mechanical spring structure has friction loss and clearance, which affects the stability of the test pressure. It is also prone to metal fatigue under high-frequency linear motion, resulting in a short service life. Insufficient repeatability: Traditional servo motors paired with mechanical transmission structures (such as gears and belts) are prone to cumulative errors, making it difficult to meet the precise positioning requirements of tiny solder joints (such as 0.1mm pitch) on high-density PCBs. Poor adaptability to large-angle rotation: Existing rotary mechanisms (such as worm gears and hollow rotary platforms) have gaps and return errors when rotating at large angles above ±90°, making them unsuitable for multi-angle tilt detection of complex PCBs. Low efficiency in high-frequency motion: Linear motion relies on cylinders or traditional servo motors, which have limited acceleration and response speed, making it difficult to meet the requirements for high-speed and convenient detection of high-density solder joints. Difficulty in balancing lightness and rigidity: Traditional aluminum alloy cantilevers are heavy and easily deformed, and lightweight materials such as carbon fiber have insufficient processing precision, resulting in significant vibration during movement, affecting detection stability.

[0003] To this end, we proposed a high-precision and high-frequency visual flying probe detection mechanism. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-precision and high-frequency visual flying probe detection mechanism, which solves the technical problems of some existing flying probe detection mechanisms, such as inconvenient adjustment of the visual system, insufficient service life and stability, insufficient repeated positioning accuracy, low high-frequency movement efficiency, and difficulty in balancing lightweight and rigidity.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions: The application discloses a high-precision high-frequency visual flying probe detection mechanism, which comprises a rotating unit, a linear driving unit and a visual monitoring unit arranged on the rotating unit, a detection probe unit arranged at the output end of the linear driving unit, and a guide connecting unit connecting the detection probe unit and the rotating unit. The guide connecting unit comprises a constant force magnetic spring, which is used for offsetting the gravity during detection of the detection probe unit. The visual monitoring unit comprises an image acquisition device and an adjusting member used for driving the image acquisition device to move along the optical axis.

[0006] Further improvement lies in that the visual monitoring unit further comprises a mounting frame connected to the output end of the rotating unit, the image acquisition device is horizontally arranged in the mounting frame, the mounting frame is provided with a prism member corresponding to the acquisition end of the image acquisition device at the other end, the adjusting member is connected to the image acquisition device and the mounting frame, and the prism member is used for transmitting the image of the detection end of the detection probe unit to the image acquisition device.

[0007] Further improvement lies in that the adjusting member comprises a connecting seat connected to the mounting frame, a movable seat slidingly arranged at one side of the connecting seat, an adjusting screw rod rotatably arranged in the connecting seat and penetrating through the connecting seat at one end, a connecting block threadedly sleeved on the outer wall of the adjusting screw rod and connected to the movable seat at one end, and a mounting seat connected to the movable seat, the mounting seat is sleeved on the outer wall of the image acquisition device, and the mounting seat is provided with a fixing structure used for fixing the connecting seat and the movable seat.

[0008] Further improvement lies in that the rotating unit comprises a DD motor and a rotating platform arranged at the output end of the DD motor, and the rotating platform is connected to the mounting frame, the linear driving unit and the constant force magnetic spring.

[0009] Further improvement lies in that the detection probe unit comprises a cantilever beam connected to the constant force magnetic spring and a detection probe main body arranged at the end of the cantilever beam away from the linear driving unit. The cantilever beam is made of carbon fiber material.

[0010] Further improvement lies in that the linear driving unit is a voice coil motor, the cantilever beam is further provided with a sliding block, and the rotating platform is provided with a vertical guide rail matched with the sliding block.

[0011] Further improvement lies in that the mounting frame is provided with a light source member at the side of the prism member facing the detection end of the detection probe unit.

[0012] A further improvement is that the light source component includes a heat dissipation shell, a diffuse reflection component arranged in the heat dissipation shell, and an annular light source body arranged on the inner wall of the heat dissipation shell, the light source body is used to illuminate the diffuse reflection component to provide light for the detection end of the detection probe unit, the vertical cross-section of the diffuse reflection component is trapezoidal, the end faces of both ends are arranged in parallel and the width of one end close to the prism component is smaller than the width of the other end face to form a gradually expanding light path channel, and the circumferential outer wall of the diffuse reflection component is arc-shaped.

[0013] A further improvement is that the detection mechanism further includes a position detection unit for monitoring the position of the detection probe unit.

[0014] A further improvement is that the position detection unit includes a connecting frame connected to the cantilever beam, a vertical grating scale arranged on the connecting frame, and a reading head arranged on the rotating unit for reading the vertical grating scale.

[0015] The beneficial effects of the present invention are: The visual monitoring unit of the present invention simplifies the optical path layout through the prism element, saving space layout. At the same time, the adjustment element is provided to facilitate quick manual adjustment of the image acquisition device, taking into account both operational convenience and adjustment accuracy, shortening the single focusing time, and being adaptable to detecting circuit boards of different thickness ranges, thereby expanding the scope of use. The present invention uses a constant force magnetic spring to replace the traditional mechanical spring structure, eliminating contact friction and gap. Combined with the direct drive characteristics of the voice coil motor, the repeated positioning accuracy is significantly improved, while the service life is extended. The present invention achieves multi-directional coordinated motion of the detection probe by coordinating the DD motor and the voice coil motor, which is suitable for the detection of complex circuit boards. The DD motor is used to achieve full-circular rotational motion with low repeatability, which meets the requirements for precise detection of 0.1mm pitch solder joints. The voice coil motor is used to achieve high-frequency linear motion of the detection probe unit in the Z-axis direction. The high-frequency motion is efficient and meets the requirements for high-speed and convenient detection of high-density solder joints. The cantilever beam of the present invention is made of carbon fiber material, which is lighter than the traditional aluminum alloy cantilever and has higher bending stiffness, effectively suppressing vibration during high-speed movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the flying probe detection mechanism of the present invention; Figure 2 For the present invention Figure 1 Another perspective structural diagram; Figure 3 Schematic diagram of the structure of the visual monitoring unit of the present invention; Figure 4 For the present invention Figure 3 Schematic diagram of the local structure in; Figure 5It is a schematic diagram of the structure of the adjusting member of the present invention; Figure 6 This is a schematic structural diagram of a light source component of the present invention; Figure 7 It is a structural schematic diagram of the position detection unit of the present invention.

[0017] In the figure: 100, rotating unit; 101, DD motor; 102, rotating platform; 200, linear drive unit; 300, visual monitoring unit; 301, mounting bracket; 302, image acquisition device; 303, prism component; 304, light source component; 3041, heat dissipation shell; 3042, diffuse reflection component; 3043, light source body; 305, adjustment component; 3051, connecting seat; 3052, adjusting screw; 3053, movable seat; 3054, connecting block; 3055, fixed structure; 3056, mounting seat; 400, detection probe unit; 401, cantilever beam; 402, detection probe body; 500, guide connection unit; 501, guide rail; 502, constant force magnetic spring; 600, position detection unit; 601, connecting bracket; 602, grating scale; 603, reading head. DETAILED DESCRIPTION

[0018] The present application is described in further detail below in conjunction with the accompanying drawings. It is necessary to point out that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technicians in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0019] Please see the attached Figure 1-5 A high-precision and high-frequency visual flying probe detection mechanism includes a rotating unit 100, a linear driving unit 200 and a visual monitoring unit 300 arranged on the rotating unit 100, a detection probe unit 400 arranged at the output end of the linear driving unit 200, and a guide connection unit 500 connecting the detection probe unit 400 and the rotating unit 100, Figure 1-2 It can be seen that the visual monitoring unit 300 and the detection probe unit 400 are parallel; Among them, the guide connection unit 500 includes a constant force magnetic spring 502, which is used to offset the Z-axis gravity during detection by the detection probe unit 400. The constant force magnetic spring 502 provides a constant axial preload through non-contact permanent magnetic repulsion, offsets the Z-axis gravity during flying probe detection, avoids friction loss and gap and service life issues of traditional mechanical spring mechanisms, and ensures that there is no return error during the process. The constant force magnetic spring 502 is a conventional structure in this field, for example, including a magnet column (fixed part) and a magnetic ring (movable part), etc., and will not be described in detail here; The visual monitoring unit 300 includes an image acquisition device 302 and an adjustment member 305 for driving the image acquisition device 302 to move along its optical axis so as to adapt to the inspection of circuit boards with different thickness ranges (such as 0.1-10 mm thickness).

[0020] Preferably, the visual monitoring unit 300 of this embodiment further includes a mounting frame 301 connected to the output end of the rotating unit 100 at one end, an image acquisition device 302 is horizontally movable in the mounting frame 301, and a prism member 303 corresponding to the acquisition end of the image acquisition device 302 is provided at the other end of the mounting frame 301. An adjustment member 305 connects the image acquisition device 302 and the mounting frame 301, and the adjustment member 305 drives the image acquisition device 302 to move, thereby changing the distance between the image acquisition device 302 and the prism member 303. The prism member 303 is used to transmit the image of the detection end of the detection probe unit 400 to the image acquisition device 302. Component 303 is a right-angle prism group, which is a conventional structure in this field. The prism component 303 is made of optical glass, and the incident surface and the exit surface are coated with a broadband anti-reflection film to reduce light energy loss. Because the image acquisition device 302 is horizontal and parallel to the detection probe unit 400, the horizontal incident light can be accurately deflected 90° through the prism component 303, so that the image acquisition device 302 can vertically capture the image of the circuit board surface and the precise position of the detection end of the detection probe unit 400. This setting method not only avoids the interference of the traditional straight light path on the movement trajectory of the detection probe unit 400, but also significantly reduces the space occupied by the overall mechanism.

[0021] Preferably, the adjusting member 305 of this embodiment includes a connecting seat 3051 connected to the mounting frame 301, a movable seat 3053 slidably arranged on one side of the connecting seat 3051, an adjusting screw 3052 rotatably arranged in the connecting seat 3051 and with one end passing through the connecting seat 3051, one end of the adjusting screw 3052 is provided with a scale handwheel for manual rotation by the user, a connecting block 3054 threadedly sleeved on the outer wall of the adjusting screw 3052 and connected to the movable seat 3053 at one end, and the end of the connecting seat 3051 facing the movable seat 3053 is hollow or has a strip-shaped through hole for the connecting block 3054 to extend and connect with the movable seat The movable seat 3053 is connected and prevents the connecting block 3054 from being driven to rotate by the adjusting screw 3052. The movable seat 3053 is connected to the mounting seat 3056. The mounting seat 3056 is U-shaped and is sleeved on the outer wall of the image acquisition device 302 to drive the image acquisition device 302 to move horizontally. The connecting seat 3051 is provided with a fixing structure 3055 for fixing the connecting seat 3051 and the movable seat 3053. The fixing structure 3055 is, for example, a bolt or a screw. When rotating the adjusting screw 3052, the fixing structure 3055 is loosened and tightened after adjustment. By rotating the scale handwheel to drive the adjustment screw 3052, the movable seat 3053, the mounting seat 3056 and the image acquisition device 302 move horizontally. For example, the adjustment range is ±5mm, and the minimum adjustment step is 0.01mm, so as to support rapid adaptation to circuit boards with a thickness of 0.1-10mm. After adjustment, it can be fixed by the fixing structure 3055.

[0022] Preferably, the rotating unit 100 of this embodiment includes a DD motor 101 and a rotating platform 102 provided at the output end of the DD motor 101, and the rotating platform 102 is connected to the mounting bracket 301, the linear drive unit 200 and the constant force magnetic spring 502; the above-mentioned DD motor 101 is a conventional device in this field, and the DD motor 101 adopts a backlash-free design and cooperates with a high-resolution encoder to achieve full-circumferential rotational motion to meet the precise detection of 0.1mm pitch solder joints. Specifically, the mounting bracket 301 and the constant force magnetic spring 502 (fixed part) are both provided on the side of the rotating platform 102, the linear drive unit 200 is provided on the bottom surface of the rotating platform 102, and a base can be installed on the top of the DD motor 101 to connect with external equipment.

[0023] Preferably, the detection probe unit 400 of this embodiment includes an L-shaped cantilever beam 401 connected to the constant force magnetic spring 502, and a detection probe body 402 arranged at the end of the cantilever beam 401 away from the linear drive unit 200. The cantilever beam 401 is specifically connected to the movable part in the constant force magnetic spring 502, and the fixed part in the constant force magnetic spring 502 is connected to the rotating platform 102. The cantilever beam 401 is made of carbon fiber material, for example, it is one-piece molded from aviation-grade T800 carbon fiber composite material. Compared with the aluminum alloy cantilever, it is lighter and has better bending stiffness, effectively suppressing vibrations during high-speed movement. The detection probe body 402 is a conventional structure in this field and can be made of tungsten steel gold-plated material. It adopts a spring pre-stressed structure to ensure reliable contact with the solder joints of the circuit board. The detection probe body 402 is detachably connected to the cantilever beam 401 to adapt to different detection point layouts.

[0024] Preferably, the linear drive unit 200 of this embodiment is a voice coil motor, which is a conventional device in this field and will not be described in detail here. The output end of the voice coil motor is connected to the cantilever beam 401, and the cantilever beam 401 is driven to reciprocate by the Lorentz force to achieve high-frequency linear motion in the Z-axis direction of the detection probe unit 400, so that the single-station detection efficiency is more than 3 times higher than that of traditional equipment. A slider is also provided on the cantilever beam 401, and a vertical guide rail 501 cooperating with the slider is provided on the rotating platform 102 to ensure the stability of the movement of the detection probe unit 400; The combination of the carbon fiber cantilever beam 401 and the voice coil motor achieves the characteristics of "light weight, high stiffness and fast acceleration". Compared with the traditional aluminum alloy structure, the movement speed is greatly improved and the vibration noise is greatly reduced.

[0025] Preferably, a light source 304 is provided on the mounting frame 301 of this embodiment and is located on the side of the prism 303 facing the detection end of the detection probe unit 400; The light source component 304 includes a heat dissipation shell 3041, which is made of high thermal conductivity aluminum alloy material for heat dissipation, a diffuse reflection component 3042 arranged in the heat dissipation shell 3041, and a ring-shaped light source body 3043 arranged on the inner wall of the heat dissipation shell 3041. The light source body 3043 is used to illuminate the diffuse reflection component 3042 to provide light for the detection end of the detection probe unit 400. The vertical cross-section of the diffuse reflection component 3042 is trapezoidal, and its two end faces are arranged in parallel and the width of one end close to the prism component 303 is smaller than the width of the other end face to form a gradually expanding light path channel. The circumferential outer wall of the diffuse reflection component 3042 is arc-shaped, ensuring that the light emitted by the light source body 3043 forms a uniformly distributed illumination light field after multiple reflections; a stable, uniform and shadow-free lighting environment is provided to the detection end of the detection probe unit 400 through the light source component 304.

[0026] Preferably, the detection mechanism of this embodiment also includes a position detection unit 600 for monitoring the position of the detection probe unit 400 and providing real-time feedback of the position signal of the cantilever beam 401. The position detection unit 600 can, for example, cooperate with an external closed-loop control system to achieve a positioning accuracy of ±1μm.

[0027] Preferably, the position detection unit 600 of this embodiment includes a connecting frame 601 connected to the cantilever beam 401, the connecting frame 601 moves up and down with the cantilever beam 401, a vertical grating scale 602 provided on the connecting frame 601, the grating scale 602 moves up and down with the connecting frame 601, and a reading head 603 provided on the rotating unit 100 for reading the vertical grating scale 602. The reading head 603 and the grating scale 602 are both conventional structures in this field. The reading head 603 can read the displacement information of the grating scale 602 in a non-contact real-time manner and convert the position signal into an electrical signal output.

[0028] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A high-precision and high-frequency visual flying probe detection mechanism, characterized in that: The invention comprises a rotating unit (100), a linear driving unit (200) and a visual monitoring unit (300) provided on the rotating unit (100), a detection probe unit (400) provided at the output end of the linear driving unit (200), and a guide connection unit (500) connecting the detection probe unit (400) and the rotating unit (100); Wherein, the guide connection unit (500) includes a constant force magnetic spring (502), and the constant force magnetic spring (502) is used to offset the gravity during detection by the detection probe unit (400); The visual monitoring unit (300) comprises an image acquisition device (302) and an adjustment member (305) for driving the image acquisition device (302) to move along its optical axis.

2. The detection mechanism according to claim 1, characterized in that: The visual monitoring unit (300) further comprises a mounting frame (301) having one end connected to the output end of the rotating unit (100); the image acquisition device (302) is horizontally movably arranged in the mounting frame (301); a prism member (303) corresponding to the acquisition end of the image acquisition device (302) is provided at the other end of the mounting frame (301); the adjusting member (305) connects the image acquisition device (302) and the mounting frame (301); and the prism member (303) is used to transmit an image from the detection end of the detection probe unit (400) to the image acquisition device (302).

3. The detection mechanism according to claim 2, characterized in that: The adjusting member (305) comprises a connecting seat (3051) connected to the mounting frame (301), a movable seat (3053) slidably arranged on one side of the connecting seat (3051), an adjusting screw (3052) rotatably arranged in the connecting seat (3051) and having one end passing through the connecting seat (3051), a connecting block (3054) threadedly sleeved on the outer wall of the adjusting screw (3052) and having one end connected to the movable seat (3053), the movable seat (3053) being connected to a mounting seat (3056), the mounting seat (3056) being sleeved on the outer wall of the image acquisition device (302), and the mounting seat (3056) being provided with a fixing structure (3055) for fixing the connecting seat (3051) and the movable seat (3053).

4. The detection mechanism according to claim 1, characterized in that: The rotating unit (100) comprises a DD motor (101) and a rotating platform (102) arranged at the output end of the DD motor (101); the rotating platform (102) is connected to a mounting frame (301), a linear drive unit (200) and a constant force magnetic spring (502).

5. The detection mechanism according to claim 4, characterized in that: The detection probe unit (400) comprises a cantilever beam (401) connected to a constant force magnetic spring (502), and a detection probe body (402) provided at one end of the cantilever beam (401) away from the linear drive unit (200); Wherein, the cantilever beam (401) is made of carbon fiber material.

6. The detection mechanism according to claim 5, characterized in that: The linear drive unit (200) is a voice coil motor, the cantilever beam (401) is further provided with a slider, and the rotating platform (102) is provided with a vertical guide rail (501) that cooperates with the slider.

7. The detection mechanism according to claim 2, characterized in that: A light source component (304) is provided on the mounting frame (301) and located on a side of the prism component (303) facing the detection end of the detection probe unit (400).

8. The detection mechanism according to claim 7, characterized in that: The light source component (304) comprises a heat dissipation housing (3041), a diffuse reflection component (3042) arranged in the heat dissipation housing (3041), and an annular light source body (3043) arranged on the inner wall of the heat dissipation housing (3041). The light source body (3043) is used to illuminate the diffuse reflection component (3042) to provide illumination for the detection end of the detection probe unit (400). The vertical cross-section of the diffuse reflection component (3042) is trapezoidal, and its two end faces are arranged in parallel. The width of one end close to the prism component (303) is smaller than the width of the other end face to form a gradually expanding light path channel. The circumferential outer wall of the diffuse reflection component (3042) is arc-shaped.

9. The detection mechanism according to claim 1, characterized in that: The detection mechanism further comprises a position detection unit (600) for monitoring the position of the detection probe unit (400).

10. The detection mechanism according to claim 9, characterized in that: The position detection unit (600) comprises a connecting frame (601) connected to the cantilever beam (401), a vertical grating scale (602) arranged on the connecting frame (601), and a reading head (603) arranged on the rotating unit (100) for reading the vertical grating scale (602).

Images