A multi-layer wiring board hole position offset detection device

Abstract

The application discloses a kind of multilayer circuit board hole position offset detection device, belong to multilayer circuit board detection technical field.A kind of multilayer circuit board hole position offset detection device, including rack, detection module is arranged on rack, further include: slidingly arranged in rack detection frame, detection module is arranged in detection frame, wherein, mark cylinder is slidably arranged in detection frame, chamber one for storing marking liquid is opened in mark cylinder, detection rod is slidably connected in chamber one, and spraying pipe is opened in mark cylinder and is communicated with chamber one;Detection table is slidably arranged on rack, and blowing hole is opened in detection table;The application is by setting mark cylinder in detection frame, detection rod is slidably arranged in mark cylinder, can be convenient for post-process identification, reduce downtime screening time, help to improve production detection efficiency, can be rechecked to hole position, prevent burr or scrap in hole from influencing judgment, lead to detection module misjudgment.

Description

Technical Field

[0001] This invention relates to the field of multilayer circuit board testing technology, and in particular to a device for detecting the offset of opening positions in multilayer circuit boards. Background Technology

[0002] Circuit boards are classified into single-sided, double-sided, and multi-layer boards according to the number of layers. Due to the increasing density of integrated circuit packaging, interconnections are highly concentrated, leading to the widespread use of multi-layer boards. Each layer of a multi-layer board consists of upper and lower inner copper foil layers and an insulating layer between them, bonded together by adhesives. The copper foil layers are not interconnected. Therefore, to achieve interconnection between the layers, through-holes are drilled, and then electroplated to form an electroplated layer on the inner wall of the through-hole and the outer surface of the multi-layer board, thus connecting the outer copper foil with the copper foil in the insulating layer. When the circuitry needs to connect to the surface layer, it must extend laterally to the electroplated layer of the through-hole, then extend upwards or downwards through the through-hole to other layers or the surface layer, and finally extend laterally from other layers or the surface layer to the desired position. Because of this, the positional accuracy of the pre-laid overlapping copper foils in each layer is crucial; any significant misalignment can lead to open circuits / short circuits, damaging the electrical performance of the product. However, due to limitations in current production technology, as well as factors such as shrinkage of circuit board materials during production and insufficient alignment accuracy during the manufacturing of multilayer circuit boards, it is not possible to guarantee completely accurate alignment between layers.

[0003] In existing technologies, X-rays are generally used to inspect the position of holes in multilayer circuit boards. However, when there are multiple holes on a multilayer circuit board and there are burrs or debris in the holes, it is impossible to identify whether the hole position is off-center, which can lead to misjudgment. In addition, when a defective product is detected, it cannot be marked, so an alarm needs to be issued and the machine needs to be stopped to wait for the staff to handle it, which seriously affects the efficiency of production inspection. Summary of the Invention

[0004] The purpose of this invention is to solve the problem in the prior art that when there are multiple holes on a multilayer circuit board and some burrs or debris remain in the holes, X-rays cannot identify them and cannot mark defective products. Therefore, this invention proposes a multilayer circuit board hole position offset detection device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A multilayer circuit board aperture position offset detection device includes a frame, a detection module mounted on the frame, and a conveyor belt rotatably mounted on the frame for transporting the circuit board. It also includes a detection frame slidably mounted on the frame, a lifting assembly for driving the detection frame to rise and fall, the detection module being disposed within the detection frame. A marking cylinder is slidably mounted within the detection frame, and a chamber for storing marking liquid is formed within the marking cylinder. A detection rod is slidably connected within the chamber, and a spray pipe communicating with the chamber is formed within the marking cylinder. A detection platform is slidably mounted on the frame, and a purge hole is formed on the detection platform. An air supply assembly for supplying air to the purge hole is disposed within the detection platform.

[0007] To facilitate detection by the detection frame, preferably, the lifting assembly includes: a piston cylinder fixedly mounted on the frame, wherein the piston cylinder has a second chamber and a third chamber, the bottoms of the second chamber and the third chamber are connected, and a piston block first is slidably connected in the second chamber, and a piston block second is slidably connected in the third chamber. A piston rod is fixedly connected to the bottom of the first piston block, and one end of the piston rod extending out of the second chamber is fixedly connected to the top of the detection frame; a pipe first is fixedly connected to the second chamber, and a pipe second is fixedly connected to the third chamber.

[0008] To prevent the spread of radiation, a limiting groove is further provided in the detection frame, and a protective plate is slidably connected in the limiting groove. Two sets of detection modules are provided, and the two sets of detection modules are respectively fixedly connected to the adjacent two sides of the inner wall of the protective plate.

[0009] In order to enable the detection rod to detect multiple holes, a first motor is fixedly connected to the detection frame, a transverse screw is fixedly connected to the output end of the first motor, a slider is threadedly connected to the transverse screw, a second motor is fixedly connected to the slider, a longitudinal screw is fixedly connected to the output end of the second motor, and the top of the marking cylinder is threadedly connected to the longitudinal screw.

[0010] To reset the detection rod, a limiting plate is slidably connected inside the first chamber. The detection rod extends into the first chamber and is fixedly connected to the bottom of the limiting plate. A spring is provided inside the first chamber, with both ends of the spring abutting against the limiting plate and the first chamber, respectively.

[0011] To further provide the marking liquid to chamber one, a storage tank is also included, which is fixedly mounted on the frame. The storage tank is connected to chamber one via a supply pipe, and a valve is fixedly connected to the supply pipe.

[0012] To prevent the marking solution from settling, the first pipe extends through the storage tank, and a stirring rod is rotatably installed inside the storage tank. The stirring rod extends into the first pipe and is fixedly connected to multiple sets of spiral blades, which are evenly distributed circumferentially on the stirring rod.

[0013] To shorten the descent distance of the detection frame, preferably, a cylinder is fixedly connected to the frame, the end of the second pipe away from the third chamber is fixedly connected to the cylinder, a support column is fixedly connected to the output end of the cylinder, and the end of the support column away from the cylinder is fixedly connected to the bottom of the detection platform.

[0014] In order to purge the hole, the air supply assembly further includes a gear rotatably mounted on the support column, wherein a rack meshing with the gear is fixedly connected to the conveyor belt, a rotating shaft is fixedly connected to the gear, a fourth chamber is opened in the detection table, and multiple sets of fan blades are fixedly connected to the rotating shaft extending into the fourth chamber, and the purging hole is connected to the fourth chamber.

[0015] Preferably, two sets of conveyor belts are coaxially arranged, the testing platform is located between the two sets of conveyor belts, and a drive source for driving the conveyor belts to rotate is fixedly installed on the frame.

[0016] Compared with the prior art, the present invention provides a multilayer circuit board aperture position offset detection device, which has the following beneficial effects:

[0017] 1. This multilayer circuit board opening position offset detection device, by setting a marking cylinder in the detection frame, can facilitate workers to quickly identify which hole position is skewed, and can also facilitate identification in subsequent processes. It can reduce downtime for screening and waiting time, and help improve production inspection efficiency. The detection rod is slidably set in the marking cylinder, which can participate in the inspection in time when the existing technology inspection module cannot detect it, thereby improving the inspection capability. It can re-measure the hole position to prevent burrs or debris in the hole from affecting the judgment and causing the inspection module to misjudge. It can also remove burrs or debris in the hole during inspection, which helps to improve the quality of multilayer circuit boards.

[0018] 2. This multilayer circuit board opening position offset detection device, by opening a blowing hole on the detection table, can blow the inside of the hole during the process of transporting the multilayer circuit board on the detection table, which can reduce dust or burrs in the hole and further improve the detection accuracy.

[0019] 3. This multi-layer circuit board opening position offset detection device can prevent the marking liquid in the storage tank from settling by adding a stirring rod, which would make the marking unclear and affect the identification.

[0020] The parts of this device not described herein are the same as or can be implemented using existing technologies. This invention, by setting a marking cylinder in the detection frame and sliding a detection rod in the marking cylinder, can facilitate workers to quickly identify which hole position is misaligned, and can also facilitate identification in subsequent processes. It can reduce downtime for screening and waiting time, and help improve production detection efficiency. It can re-test the hole position to prevent burrs or debris in the hole from affecting the judgment and causing the detection module to misjudge. It can also remove burrs or debris in the hole during detection, which helps improve the quality of multilayer circuit boards. Attached Figure Description

[0021] Figure 1 This is a front view of a multilayer circuit board aperture offset detection device proposed in this invention;

[0022] Figure 2 This invention provides a device for detecting the offset of openings in multilayer circuit boards. Figure 1 Enlarged view of section A;

[0023] Figure 3 This is a schematic diagram of the conveyor belt structure of a multilayer circuit board opening position offset detection device proposed in this invention;

[0024] Figure 4 This is a schematic diagram of the detection frame of a multilayer circuit board opening position offset detection device proposed in this invention;

[0025] Figure 5 This invention provides a device for detecting the offset of openings in multilayer circuit boards. Figure 4 Schematic diagram of Part B in the middle section;

[0026] Figure 6 This is a schematic diagram of the structure of the detection platform of the multilayer circuit board opening position offset detection device proposed in this invention.

[0027] In the diagram: 1. Frame; 101. Protective cover; 2. Conveyor belt; 201. Rack; 3. Detection frame; 301. Protective plate; 302. Detection module; 303. First motor; 304. Transverse screw; 305. Second motor; 306. Longitudinal screw; 4. Piston cylinder; 401. Piston block one; 402. Piston block two; 403. Piston rod; 404. Pipe one; 405. Pipe two; 5. Liquid storage tank; 501. Stirring rod; 502. Liquid supply pipe; 503. Spiral blade; 6. Detection platform; 601. Chamber four; 602. Purge hole; 7. Marking cylinder; 701. Detection rod; 702. Chamber one; 703. Spring; 704. Injection pipe; 705. Limiting plate; 8. Cylinder; 801. Support column; 802. Gear; 803. Rotating shaft; 804. Fan blade. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0029] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0030] Example:

[0031] Reference Figures 1-6A multilayer circuit board aperture position offset detection device includes a frame 1, on which a protective cover 101 is fixedly mounted. The protective cover 101 spans across the frame 1, and a conveyor belt 2 passes through the inside of the protective cover 101 to reduce dust and other contaminants falling on the multilayer circuit board, making the detection data more accurate. A detection module 302 is installed inside the protective cover 101. The detection module 302 uses existing X-ray detection technology. During use, the side of the multilayer circuit board is irradiated to observe and determine whether the aperture position offset is within the required range. If it is within the range, it is a qualified product; otherwise, it is a defective product. A rotatable conveyor belt 2 is mounted on the frame 1 for conveying... The system includes two coaxially arranged conveyor belts 2 for transporting circuit boards. A testing platform 6 is located between the two conveyor belts 2, and a drive source for rotating the conveyor belts 2 is fixedly mounted on the frame 1. Both conveyor belts 2 are driven synchronously forward by a single shaft. The multilayer circuit board spans across the two conveyor belts 2. The system also includes a testing frame 3 slidably mounted within a protective cover 101. The protective cover 101 has a lifting assembly for raising and lowering the testing frame 3, facilitating the illumination testing of the multilayer circuit board with the testing module 302. A limiting groove is provided within the testing frame 3 to prevent the protective plate 301 from detaching from the testing frame 3 and to ensure the protective plate 301 can... A protective plate 301 is slidably connected within the limiting groove to reduce the diffusion of radiation generated by the detection module 302 during detection. Two sets of detection modules 302 are provided, each fixedly connected to adjacent sides of the inner wall of the protective plate 301. This allows for detection of the multilayer circuit board in both X and Y directions. Analysis of the data in both directions determines whether the hole offset dimensions meet requirements. A marking cylinder 7 is slidably installed within the detection frame 3. The marking cylinder 7 contains a chamber 702 for storing a colored marking liquid. A detection rod 7 is slidably connected within chamber 702. 01. The diameter of the detection rod 701 is smaller than the diameter of the hole on the multilayer circuit board, and the diameter of the detection rod 701 is greater than or equal to the maximum allowable offset size. That is, when the detection rod 701 can pass through the hole on the multilayer circuit board, the hole position offset size meets the requirements. Conversely, when the detection rod 701 cannot pass through even under the elastic force of the spring 703, the offset size does not meet the requirements. The marking cylinder 7 is provided with a spray pipe 704 connected to the chamber 702. A valve is installed on the spray pipe 704. The valve is an overflow valve. When the pressure in the chamber 702 reaches the set value, the marking liquid in the chamber 702 will be sprayed out through the spray pipe 704.A testing platform 6 is slidably mounted on the frame 1, located directly below the testing frame 3. When the testing platform 6 slides upwards, it can deliver the multi-layer circuit board from the conveyor belt 2 to the testing frame 3 for testing. It can also blow away burrs, dust, or other debris from the holes in the circuit board, reducing the impact on the testing data. The testing platform 6 has a blowing hole 602, and an air supply assembly is installed inside the testing platform 6 to supply air to the blowing hole 602.

[0032] In operation, when the multilayer circuit board moves above the testing platform 6, gas is introduced into chamber two through pipe 404. During this process, piston block 401 slides downward along chamber two, causing the testing frame 3 to move closer to the multilayer circuit board. Simultaneously, as piston block 401 slides downward, it forces the air in chamber two into chamber three, pushing piston block 402 upward along chamber three. Then, the air in chamber three above piston block 402 is sent to cylinder 8. Cylinder 8 raises the support column 801, and the testing platform 6, fixed to the top of the support column 801, lifts the multilayer circuit board towards the testing platform. As the circuit moves closer to frame 3, the air supply component supplies air to the purge hole 602. The purge hole 602 can clean the multi-layer circuit board, preventing burrs or dust from remaining inside the holes and causing misjudgment. This continues until the protective plate 301 covers the multi-layer circuit board. The detection module 302 can perform irradiation detection on the two adjacent sides of the multi-layer circuit board. When the hole offset dimension meets the requirements, the detection ends, and the reverse operation causes the multi-layer circuit board to fall back onto the conveyor belt 2, which then transports it away. Then, the next piece can be detected. If the detection does not meet the requirements or the multi-layer circuit board has too many holes, and the detection module 302 cannot identify it, the first motor 3... 03 and the second motor 305 cooperate to drive the marking cylinder 7, along with the detection rod 701, to move sequentially above the hole on the multilayer circuit board. Gas continues to be introduced into the second chamber through the first pipe 404. The detection frame 3 can then lower the detection rod 701 further and insert it into the hole on the multilayer circuit board. When the detection rod 701 can pass through the hole on the multilayer circuit board, the hole position offset dimension meets the requirements. Conversely, when the detection rod 701 cannot pass through even under the elastic force of the spring 703, the offset dimension does not meet the requirements. In this case, the detection rod 701 will instead push the limiting plate 705 to slide upward along the first chamber 702. The limiting plate 705 can spray the marking liquid in chamber 702 onto the end face of the hole through the spray pipe 704. This process is repeated until all holes on the multilayer circuit board have been inspected by the detection rod 701. After the inspection is completed, a report is sent to the staff so that they can quickly understand the abnormality. The marking can help the staff identify which hole is misaligned and can also facilitate the identification of subsequent processes. It can reduce downtime and waiting time and help improve production inspection efficiency. Finally, after the inspection is completed, the multilayer circuit board is put back onto the conveyor belt 2 and transported away by the conveyor belt 2. Then the next piece can be inspected.

[0033] Reference Figure 1The lifting assembly includes: a piston cylinder 4 fixedly mounted on the frame 1, wherein the piston cylinder 4 has a second chamber and a third chamber, the bottoms of the second and third chambers are connected, and a piston block 401 is slidably connected in the second chamber, and a piston block 402 is slidably connected in the third chamber. A piston rod 403 is fixedly connected to the bottom of the piston block 401, and one end of the piston rod 403 extending out of the second chamber is fixedly connected to the top of the detection frame 3; a pipe 404 is fixedly connected to the second chamber, and a pipe 405 is fixedly connected to the third chamber; a cylinder 8 is fixedly connected to the frame 1, the end of the pipe 405 away from the third chamber is fixedly connected to the cylinder 8, and a support column 801 is fixedly connected to the output end of the cylinder 8. The end of the support column 801 away from the cylinder 8 is fixedly connected to the bottom of the detection platform 6. In use, gas is introduced into the second chamber through the pipe 404. During the process, piston block 401 slides downward along chamber 2. At the same time, as piston block 401 slides downward, it forces the air in chamber 2 into chamber 3, pushing piston block 402 upward along chamber 3. Then, the air in chamber 3 above piston block 402 is sent to cylinder 8. Cylinder 8 raises support column 801. At this time, the detection platform 6 fixed on top of support column 801 can lift the multilayer circuit board and move it closer to the detection frame 3. After the detection is completed, the air in chamber 2 above piston block 401 is extracted through pipe 404. Piston block 401 will slide upward, and piston block 402 will slide downward under the suction of piston block 401. Piston block 402 will draw the air back from cylinder 8, and then detection platform 6 will descend, causing the multilayer circuit board to fall back onto conveyor belt 2.

[0034] Reference Figure 1 , Figure 4 and Figure 5A first motor 303 is fixedly connected to the detection frame 3. A transverse screw 304 is fixedly connected to the output end of the first motor 303. A slider is threaded onto the transverse screw 304. A second motor 305 is fixedly connected to the slider. A longitudinal screw 306 is fixedly connected to the output end of the second motor 305. The top of the marking cylinder 7 is threaded onto the longitudinal screw 306. A limit plate 705 is slidably connected inside the first chamber 702. The detection rod 701 extends into the first chamber 702 and is fixedly connected to the bottom of the limit plate 705. A spring 703 is installed inside the first chamber 702. The spring 703 is pre-compressed and has a certain pressure. When the multilayer circuit board... When there are burrs or debris inside the hole, the detection rod 701 can remove the burrs or debris, which can improve the quality of the multilayer circuit board. The two ends of the spring 703 abut against the limiting plate 705 and the chamber 702 respectively. In use, when the first motor 303 rotates with the transverse screw 304, the slider can move left and right with the second motor 305 and the components on it. When the second motor 305 rotates with the longitudinal screw 306, the marking cylinder 7 can move back and forth under the drive of the longitudinal screw 306, which makes it convenient to move the detection rod 701 above the hole position of the multilayer circuit board, which facilitates the detection of multiple holes and improves the detection range.

[0035] Reference Figure 1 and Figure 2 A multilayer circuit board aperture position offset detection device further includes a liquid storage tank 5 fixedly mounted on a frame 1. The liquid storage tank 5 is connected to a chamber 702 via a supply pipe 502. A valve, typically a one-way valve, is fixedly connected to the supply pipe 502 to prevent the marking liquid in the chamber 702 from flowing back into the liquid storage tank 5 under pressure. When the marking liquid is sprayed out of the chamber 702, the detection frame 3 rises, and the limit plate 705 resets under the action of a spring 703. The marking liquid can be drawn from the liquid storage tank 5 via the supply pipe 502. (Pipe 404) A stirring rod 501 is rotatably installed inside the storage tank 5. The stirring rod 501 extends into the pipe 404 and is fixedly connected to multiple sets of spiral blades 503. The multiple sets of spiral blades 503 are evenly distributed on the stirring rod 501 in a circle. When there is airflow in the pipe 404, the spiral blades 503 can drive the stirring rod 501 to rotate. Then the stirring rod 501 will stir the marking liquid in the storage tank 5 to prevent the marking liquid from settling, which would make the color of the marking liquid at the spray nozzle 704 indistinct and impossible for the staff to identify.

[0036] Reference Figure 1 , Figure 3 and Figure 6The air supply assembly includes a gear 802 rotatably mounted on a support column 801. A rack 201 meshing with the gear 802 is fixedly connected to the conveyor belt 2. A rotating shaft 803 is fixedly connected to the gear 802. A chamber 601 is opened inside the detection table 6. Multiple sets of fan blades 804 are fixedly connected to the rotating shaft 803 inside the chamber 601. The purging hole 602 is connected to the chamber 601. In use, when the cylinder 8 lifts the support column 801, the gear 802 meshes with the rack 201 on the side of the conveyor belt 2. The conveyor belt 2 continues to move forward, and the rack 201 drives the gear 802 to rotate. During this process, the rotating shaft 803 rotates the fan blades 804. The fan blades 804 generate a breeze in the chamber 601, which is then blown out through the purging hole 602 to clean the holes on the multilayer circuit board. This can reduce the amount of dust or burrs remaining in the holes and help improve the detection accuracy.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multilayer circuit board opening position offset detection device, comprising a frame (1), wherein a detection module (302) is disposed on the frame (1), and a conveyor belt (2) for conveying circuit boards is rotatably disposed on the frame (1), characterized in that, Also includes: A detection frame (3) is slidably mounted on the frame (1). The frame (1) is equipped with a lifting assembly for driving the detection frame (3) to rise and fall. The detection module (302) is located inside the detection frame (3). The marking tube (7) is slidably arranged inside the detection frame (3). A chamber (702) for storing marking liquid is opened inside the marking tube (7). A detection rod (701) is slidably connected inside the chamber (702). A spray pipe (704) communicating with the chamber (702) is opened inside the marking tube (7). A testing platform (6) is slidably mounted on the frame (1). A purge hole (602) is provided on the testing platform (6). An air supply component for supplying air to the purge hole (602) is provided inside the testing platform (6). The lifting assembly includes a piston cylinder (4) fixedly mounted on the frame (1). The piston cylinder (4) has a second chamber and a third chamber. The bottoms of the second chamber and the third chamber are connected. A piston block (401) is slidably connected in the second chamber, and a piston block (402) is slidably connected in the third chamber. A piston rod (403) is fixedly connected to the bottom of the piston block (401), and one end of the piston rod (403) extending out of the second chamber is fixedly connected to the top of the detection frame (3). The second chamber is fixedly connected to the first pipe (404), and the third chamber is fixedly connected to the second pipe (405). A cylinder (8) is fixedly connected to the frame (1). One end of the second pipe (405) away from the third chamber is fixedly connected to the cylinder (8). A support column (801) is fixedly connected to the output end of the cylinder (8). One end of the support column (801) away from the cylinder (8) is fixedly connected to the bottom of the testing table (6). The gas supply assembly includes: Rotate the gear (802) mounted on the support column (801). Among them, a rack (201) that meshes with a gear (802) is fixedly connected to the conveyor belt (2), a rotating shaft (803) is fixedly connected to the gear (802), a fourth chamber (601) is opened in the detection table (6), the rotating shaft (803) extends into the fourth chamber (601) and is fixedly connected to multiple sets of fan blades (804), and the blow hole (602) is connected to the fourth chamber (601).

2. The multilayer circuit board aperture offset detection device according to claim 1, characterized in that, The detection frame (3) has a limiting groove, and a protective plate (301) is slidably connected in the limiting groove. The detection module (302) is provided in two sets, and the two sets of detection modules (302) are respectively fixedly connected to the adjacent two sides of the inner wall of the protective plate (301).

3. The multilayer circuit board aperture position offset detection device according to claim 2, characterized in that, A first motor (303) is fixedly connected to the detection frame (3). A transverse screw (304) is fixedly connected to the output end of the first motor (303). A slider is threadedly connected to the transverse screw (304). A second motor (305) is fixedly connected to the slider. A longitudinal screw (306) is fixedly connected to the output end of the second motor (305). The top of the marking cylinder (7) is threadedly connected to the longitudinal screw (306).

4. The multilayer circuit board aperture offset detection device according to claim 3, characterized in that, A limiting plate (705) is slidably connected inside the first chamber (702). The detection rod (701) extends into the first chamber (702) and is fixedly connected to the bottom of the limiting plate (705). A spring (703) is provided inside the first chamber (702). The two ends of the spring (703) abut against the limiting plate (705) and the first chamber (702) respectively.

5. The multilayer circuit board aperture position offset detection device according to claim 4, characterized in that, It also includes a liquid storage tank (5) fixedly installed on the frame (1), the liquid storage tank (5) being connected to the first chamber (702) via a liquid supply pipe (502), and a valve being fixedly connected to the liquid supply pipe (502).

6. The multilayer circuit board aperture offset detection device according to claim 5, characterized in that, The first pipe (404) passes through the liquid storage tank (5). A stirring rod (501) is rotatably installed inside the liquid storage tank (5). The stirring rod (501) extends into the first pipe (404) and is fixedly connected to multiple sets of spiral blades (503). The multiple sets of spiral blades (503) are evenly distributed on the stirring rod (501) in a circle.

7. The multilayer circuit board aperture offset detection device according to claim 6, characterized in that, The conveyor belt (2) is coaxially arranged in two sets, the detection table (6) is located between the two sets of conveyor belts (2), and the frame (1) is fixedly provided with a drive source for driving the conveyor belt (2) to rotate.

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