Drilling dirt removing device for thick PCB (Printed Circuit Board)

Abstract

The invention provides a drilling dirt removing device for a thick PCB, and relates to the technical field of PCBs. The device comprises a supporting mechanism, a decontamination mechanism is arranged on the side portion of the supporting mechanism, an upper header is arranged above the supporting mechanism in a liftable mode, a lower header is arranged below the supporting mechanism in a liftable mode, and a plurality of decontamination assemblies are arranged at the bottom of the upper header and the top of the lower header. The positions of the multiple decontamination assemblies at the bottom of the upper header and the top of the lower header correspond to the positions of holes in the thick PCB, each decontamination assembly comprises a decontamination pipe communicated with the corresponding upper header or lower header, the end of each decontamination pipe is provided with a decontamination head making contact with the thick PCB, and a through cavity is formed in each decontamination head; a first circulating pipeline and a second circulating pipeline are communicated between the upper header and the lower header, a swelling agent circularly flows in the first circulating pipeline, and an oxidizing agent circularly flows in the second circulating pipeline. The agent dosage is greatly reduced, and the drilling dirt removal efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of PCB boards, and in particular to a PCB thick board decontamination device. Background Art

[0002] Currently, the PCB production process includes inner layer fabrication, lamination, drilling, and hole metallization. After drilling is completed, drill smears remain within the holes that need to be removed. Due to the localized temperature increase within the holes, the resin softens and melts into a paste, which adheres to the hole walls and forms slag after cooling. Currently, drill smear removal is primarily performed through chemical immersion combined with dynamic spraying. This method consumes a large amount of chemical. Furthermore, for thick PCBs, due to the larger hole diameters and depths, immersion is less efficient in removing smears from the hole walls. Summary of the Invention

[0003] The purpose of the present invention is to develop a PCB thick plate drill contamination removal device which can greatly reduce the amount of reagents used and improve the drill contamination removal efficiency.

[0004] The present invention is achieved through the following technical solutions:

[0005] A PCB thick plate decontamination device, comprising:

[0006] Support mechanism, supporting and fixing the thick PCB board;

[0007] The decontamination mechanism is arranged on the side of the support mechanism and includes:

[0008] The upper header box is arbitrarily arranged above the supporting mechanism;

[0009] The lower connecting box is arranged below the supporting mechanism in a liftable manner;

[0010] Multiple decontamination components are located at the bottom of the upper header and the top of the lower header;

[0011] The positions of the multiple decontamination components at the bottom of the upper header and the top of the lower header correspond to the positions of the holes on the PCB thick plate. The decontamination components include a decontamination pipe connected to the corresponding upper header or lower header, and a decontamination head is provided at the end of the decontamination pipe for contacting the PCB thick plate. The decontamination head has a through cavity.

[0012] A first circulation pipeline and a second circulation pipeline are connected between the upper header and the lower header. A swelling agent circulates in the first circulation pipeline, and an oxidizing agent circulates in the second circulation pipeline.

[0013] Optionally, the cavity of the decontamination head is bullet-shaped, the cavity gradually increases in a direction away from the decontamination tube, and the inner diameter of the open end of the decontamination head is larger than the inner diameter of the corresponding hole.

[0014] Optionally, a sealing ring is provided on the outer edge of the opening end of the decontamination head for contacting the PCB thick plate.

[0015] Optionally, a circulation pump and a filter are provided on both the first circulation pipeline and the second circulation pipeline, and a solenoid valve is provided on both the first circulation pipeline and the second circulation pipeline at the connection points with the upper header and the lower header.

[0016] Optionally, a swelling agent tank is provided on the first circulation pipeline, an organic solvent for swelling the resin is provided in the swelling agent tank, and a heater is provided in the swelling agent tank.

[0017] Optionally, an oxidizing agent tank is provided on the second circulation pipeline, wherein the oxidizing agent tank is provided with an oxide for oxidatively decomposing the resin, and the oxidizing agent tank is provided with a heater.

[0018] Optionally, the lower connecting box is connected to a drain pipe, a solenoid valve is provided on the drain pipe, and the drain pipe is connected to a waste liquid tank.

[0019] Optionally, the upper pipeline of the upper header is connected to a neutralizing agent tank, the neutralizing agent tank is provided with a neutralizing agent, the neutralizing agent tank is provided with a heater, and the pipeline between the neutralizing agent tank and the upper header is provided with a solenoid valve and a delivery pump.

[0020] Optionally, an air inlet pipe and a water inlet pipe are connected to the upper header, and solenoid valves are provided on the air inlet pipe and the water inlet pipe. The air inlet pipe is connected to a nitrogen source, and the water inlet pipe is connected to a water source.

[0021] Optionally, the support mechanism includes a vertically arranged enclosure arranged along the edge track of the PCB thick plate, and the inner wall of the enclosure is provided with a circle of horizontally arranged support rings;

[0022] A slider is provided on the enclosure above the support ring. The slider slides horizontally and is perpendicular to the inner wall of the enclosure where it is located. A cylinder for driving the slider to slide is provided on the outer wall of the enclosure. The distance between the bottom of the slider and the support ring is adapted to the thickness of the PCB thick plate, and the bottom of the outer end of the slider is an arc surface.

[0023] The beneficial effects of the present invention are:

[0024] The present invention is aimed at holes in thick PCB boards. By establishing a closed circulation pipeline with the holes, the drilling contamination in the holes can be accurately removed. The amount of reagent used is greatly reduced, and the reagent flows in the holes, avoiding low contact efficiency between the inside of the holes and the reagent, thereby increasing the contact amount between the reagent and the inside of the holes, and improving the efficiency of drilling contamination removal. Since the opening end of the decontamination head is large, impurities generated during the drilling process and falling on the periphery of the hole are also inside the decontamination head and are cleaned. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0026] Figure 1 It is a structural diagram of the present invention;

[0027] Figure 2 This is a structural diagram of the decontamination component.

[0028] Figure numerals: 1. enclosure; 2. slider; 3. support ring; 4. upper connecting box; 5. lower connecting box; 6. decontamination pipe; 7. decontamination head; 71. cavity; 72. sealing ring; 8. waste liquid tank; 9. drain pipe; 10. neutralization agent tank; 11. air inlet pipe; 12. water inlet pipe; 13. first circulation pipe; 14. second circulation pipe; 15. swelling agent tank; 16. oxidizing agent tank; 17. filter. DETAILED DESCRIPTION

[0029] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0032] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0033] like Figure 1 and Figure 2 As shown, the present invention discloses a PCB thick plate decontamination device, including a support mechanism and a decontamination mechanism. The support mechanism supports and fixes the PCB thick plate. The support mechanism includes a vertically arranged enclosure 1 arranged along the edge track of the PCB thick plate. The inner wall of the enclosure 1 is provided with a circle of horizontally arranged support rings 3.

[0034] A slider 2 is slidably provided on the enclosure 1 above the support ring 3 . The slider 2 slides horizontally and perpendicularly to the inner wall of the enclosure 1 where it is located. A cylinder for driving the slider 2 to slide is correspondingly provided on the outer wall of the enclosure 1 .

[0035] The spacing between the bottom of slider 2 and support ring 3 matches the thickness of the thick PCB board, and the bottom outer end of slider 2 has an arc-shaped surface. If the thick PCB board does not fully contact the support ring 3, the top edge of the PCB board is slightly higher than the bottom of slider 2. When slider 2 slides out from the side wall of enclosure 1, the arc-shaped surface at the bottom outer end of slider 2 first contacts the edge of the thick PCB board. As slider 2 slides, its arc-shaped surface and the sliding cooperation of the thick PCB board push the thick PCB board downward onto support ring 3 to achieve positioning. The cooperation between the bottom of slider 2 and support ring 3 clamps and secures the thick PCB board.

[0036] The decontamination mechanism includes an upper connecting box 4 arranged above the support ring 3 and a lower connecting box 5 arranged below the support ring 3. The top of the upper connecting box 4 and the bottom of the lower connecting box 5 are both connected to a driving device (not shown in the figure), which can drive the upper connecting box 4 and the lower connecting box 5 to move up and down.

[0037] Multiple groups of symmetrical decontamination components are provided at the bottom of the upper header 4 and the top of the lower header 5. The multiple groups of decontamination components correspond to the hole positions of the PCB thick plate. After the PCB thick plate is fixed on the support mechanism, the upper header 4 and the lower header 5 can be moved to make the decontamination components on the upper and lower sides of the PCB thick plate contact with the holes of the PCB thick plate.

[0038] The decontamination assembly includes a decontamination pipe 6 vertically connected to the corresponding upper header 4 or lower header 5 , and the decontamination pipe 6 is communicated with the corresponding upper header 4 or lower header 5 .

[0039] The end of the decontamination tube 6 is connected to a decontamination head 7, which has a bullet-shaped cavity 71 extending through it. The cavity 71 gradually increases in size as it moves away from the decontamination tube 6. The inner diameter of the open end of the decontamination head 7, that is, the inner diameter of the end of the cavity 71 in the decontamination head 7 away from the decontamination tube 6, is larger than the inner diameter of the corresponding hole in the thick PCB board. This ensures that when the decontamination head 7 is aligned with the hole, the hole is located inside the open end of the decontamination head 7 within a certain tolerance.

[0040] A sealing ring 72 is provided on the outer edge of the opening end of the decontamination head 7 , and the sealing ring 72 contacts the PCB thick plate outside the hole.

[0041] The upper header 4 and the lower header 5 are connected by a first circulation pipe 13 and a second circulation pipe 14. The first circulation pipe 13 and the second circulation pipe 14 are both provided with a circulation pump and a filter 17. Solenoid valves are both provided on the first circulation pipe 13 and the second circulation pipe 14 at the connection points with the upper header 4 and the lower header 5.

[0042] A swelling agent tank 15 is provided on the first circulation pipe 13 , and an organic solvent for swelling the resin is provided in the swelling agent tank 15 .

[0043] An oxidizing agent tank 16 is provided on the second circulation pipe 14 , and an oxidizing agent tank 16 is provided with an oxide for oxidatively decomposing the resin.

[0044] The lower header 5 is also connected to a drain pipe 9 , which is provided with a solenoid valve and is connected to a waste liquid tank 8 .

[0045] The upper header 4 is also connected to a neutralizing agent tank 10 through a pipeline. The neutralizing agent tank 10 is provided with a neutralizing agent. A solenoid valve and a delivery pump are provided on the pipeline between the neutralizing agent tank 10 and the upper header 4.

[0046] The neutralizing agent tank 10 , the swelling agent tank 15 and the oxidizing agent tank 16 are all provided with heaters, and the temperatures of the agents are controlled by the heaters.

[0047] The upper header 4 is also connected to an air inlet pipe 11 and a water inlet pipe 12, and electromagnetic valves are provided on the air inlet pipe 11 and the water inlet pipe 12. The air inlet pipe 11 is connected to a nitrogen source, and the water inlet pipe 12 is connected to a clean water source.

[0048] To remove drill contamination from a thick PCB, the PCB is placed on the support mechanism, which positions and secures it. Then, the upper header 4 descends and the lower header 5 ascends. The multiple cleaning heads 7 of the cleaning components at the bottom of the upper header 4 align with the corresponding holes and descend until they contact the top surface of the PCB. The multiple cleaning heads 7 of the cleaning components at the top of the lower header 5 align with the corresponding holes and ascend until they contact the bottom surface of the PCB. The corresponding cleaning heads 7 cover the upper and lower sides of the holes, and sealing rings 72 seal against the PCB.

[0049] The two solenoid valves of the first circulation pipe 13 are opened and the circulation pump is working. The swelling agent in the swelling agent tank 15 enters the upper header 4 along the first circulation pipe 13, and then enters the decontamination pipe 6 of multiple decontamination components from the upper header 4. The decontamination head 7 at the end of the decontamination pipe 6 enters the hole. After passing through the hole, the swelling agent enters the decontamination head 7 and decontamination pipe 6 of the decontamination component on the lower side of the hole in turn, and is collected into the lower header 5. Then, the filter 17 on the first circulation pipe 13 is entered from the lower header 5 and then flows back into the swelling agent tank 15. Through circulation, the swelling agent performs swelling pretreatment on the hole. Before the swelling agent circulates, the heater in the swelling agent tank 15 is operated to keep the swelling agent within the operating temperature range. The filter 17 filters out impurities in the swelling agent. The swelling agent recycled in the swelling agent tank 15 can be reused or replaced. During regeneration, the heavy components are discarded through membrane distillation, and the fraction is supplemented with a certain amount of new agent for reuse.

[0050] After the swelling agent completes the swelling pretreatment in the hole, the two solenoid valves on the first circulation pipe 13 are closed, and then the solenoid valve on the second circulation pipe 14 near the upper header 4 is opened, and the solenoid valve near the lower header 5 remains closed. The circulation pump works, and the solenoid valve on the discharge pipe 9 is opened. The oxidizing agent in the oxidizing agent tank 16 enters the upper header 4 along the second circulation pipe 14, and then enters the decontamination pipes 6 and decontamination heads 7 of multiple decontamination components in turn from the upper header 4 and enters the hole, and then flows from the hole into the lower decontamination head 7, decontamination pipe 6 and lower header 5, and then enters the waste liquid tank 8 through the discharge pipe 9, so that the initial oxidizing agent flushes the upper header 4, decontamination components and lower header 5 to remove residual swelling agent, and the flushing waste liquid is collected by the waste liquid tank 8. After flushing is complete, the solenoid valve in drain pipe 9 closes, and the solenoid valve in second circulation pipe 14 near lower header 5 opens, allowing the oxidant to circulate. The oxidant output from lower header 5 passes through filter 17 and flows back into oxidant tank 16, where it oxidizes and decomposes impurities within the pores. Before the oxidant circulates, the heater in oxidant tank 16 operates to keep the oxidant within the operating temperature range. Filter 17 removes impurities from the oxidant, allowing the oxidant in oxidant tank 16 to be regenerated or replaced. The oxidant's primary component is typically potassium permanganate, which can be regenerated through electrolysis.

[0051] After the oxidizing agent completes its circulation and removes the residue in the wells, the two solenoid valves in the second circulation pipe 14 are closed. Then, the solenoid valve and delivery pump in the pipeline between the neutralizing agent tank 10 and the upper header 4 are opened, and the solenoid valve on the discharge pipe 9 is opened. The neutralizing agent in the neutralizing agent tank 10 is input into the upper header 4, and then into the decontamination pipe 6, the decontamination head 7, the wells, and the decontamination head 7 and decontamination pipe 6 connected to the lower header 5. Finally, it is output from the lower header 5 to the discharge pipe 9 and into the waste liquid tank 8. The neutralizing agent neutralizes the residual oxidizing agent in the wells. Before the neutralizing agent enters the upper header 4, the heater in the neutralizing agent tank 10 is activated to keep the neutralizing agent within the operating temperature range.

[0052] After the neutralizing agent has completely removed any residual oxides from the holes, the solenoid valve and delivery pump between the neutralizing agent tank 10 and the upper header 4 are stopped. The solenoid valve on the water inlet pipe 12 is then opened, allowing clean water to flush the upper header 4, the decontamination assembly, and the lower header 5. The flushing water ultimately enters the waste liquid tank 8 through the drain pipe 9. After the flushing is complete, the solenoid valve on the water inlet pipe 12 is closed, and the solenoid valve on the air inlet pipe 11 is opened. Dry nitrogen is then introduced through the air inlet pipe 11 into the loading and unloading system, the decontamination assembly, and the lower header 5, assisting in cleaning and drying the holes. Upon completion, the upper and lower headers 4 and 5 drive the decontamination assembly away from the PCB slab, and the PCB slab is then removed.

[0053] The present invention aims at drilling contamination in holes with a diameter of more than 2 mm in thick PCB boards. By establishing a closed circulation pipeline with the hole, the drilling contamination in the hole is accurately removed, the amount of reagent used is greatly reduced, and the reagent flows in the hole, avoiding low contact efficiency between the inside of the hole and the reagent, increasing the contact amount between the reagent and the inside of the hole, and improving the efficiency of drilling contamination removal. Since the opening end of the decontamination head 7 is larger, impurities generated during the drilling process and falling on the periphery of the hole are also inside the decontamination head 7 and are cleaned.

[0054] The above embodiments are only preferred embodiments of the present invention and are not limitations on the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A PCB thick plate decontamination device, characterized in that: include: Support mechanism, supporting and fixing the thick PCB board; The decontamination mechanism is arranged on the side of the support mechanism and includes: The upper header box is arbitrarily arranged above the supporting mechanism; The lower connecting box is arranged below the supporting mechanism in a liftable manner; Multiple decontamination components are located at the bottom of the upper header and the top of the lower header; The positions of the multiple decontamination components at the bottom of the upper header and the top of the lower header correspond to the positions of the holes on the PCB thick plate. The decontamination components include a decontamination pipe connected to the corresponding upper header or lower header, and a decontamination head is provided at the end of the decontamination pipe for contacting the PCB thick plate. The decontamination head has a through cavity. A first circulation pipeline and a second circulation pipeline are connected between the upper header and the lower header. A swelling agent circulates in the first circulation pipeline, and an oxidizing agent circulates in the second circulation pipeline.

2. The PCB thick plate decontamination device according to claim 1, characterized in that: The cavity of the decontamination head is in the shape of a bullet, and the cavity gradually increases in the direction away from the decontamination pipe. The inner diameter of the opening end of the decontamination head is larger than the inner diameter of the corresponding hole.

3. The PCB thick plate decontamination device according to claim 2, characterized in that: The outer edge of the open end of the decontamination head is provided with a sealing ring that contacts the PCB thick plate.

4. The PCB thick plate decontamination device according to claim 1, characterized in that: The first circulation pipeline and the second circulation pipeline are both provided with a circulation pump and a filter, and the first circulation pipeline and the second circulation pipeline at the connection points with the upper header and the lower header are both provided with a solenoid valve.

5. The PCB thick plate decontamination device according to claim 4, characterized in that: A swelling agent tank is provided on the first circulation pipeline. An organic solvent for swelling the resin is provided in the swelling agent tank. A heater is provided in the swelling agent tank.

6. The PCB thick plate decontamination device according to claim 4, characterized in that: An oxidizing agent tank is provided on the second circulation pipeline. An oxidizing agent for oxidizing and decomposing the resin is provided in the oxidizing agent tank. A heater is provided in the oxidizing agent tank.

7. The PCB thick plate decontamination device according to claim 1, characterized in that: The lower connecting box is connected with a drain pipe, a solenoid valve is provided on the drain pipe, and the drain pipe is connected with a waste liquid tank.

8. The PCB thick plate decontamination device according to claim 1, characterized in that: The upper pipeline of the upper header is connected with a neutralizing agent tank, the neutralizing agent tank is provided with a neutralizing agent, the neutralizing agent tank is provided with a heater, and the pipeline between the neutralizing agent tank and the upper header is provided with a solenoid valve and a delivery pump.

9. The PCB thick plate decontamination device according to claim 1, characterized in that: The upper header is connected with an air inlet pipe and a water inlet pipe, and electromagnetic valves are provided on the air inlet pipe and the water inlet pipe. The air inlet pipe is connected with a nitrogen source, and the water inlet pipe is connected with a water source.

10. The PCB thick plate decontamination device according to any one of claims 1 to 9, characterized in that: The support mechanism includes a vertically arranged enclosure arranged along the edge track of the PCB thick plate, and the inner wall of the enclosure is provided with a circle of horizontally arranged support rings; A slider is provided on the enclosure above the support ring. The slider slides horizontally and is perpendicular to the inner wall of the enclosure where it is located. A cylinder for driving the slider to slide is provided on the outer wall of the enclosure. The distance between the bottom of the slider and the support ring is adapted to the thickness of the PCB thick plate, and the bottom of the outer end of the slider is an arc surface.

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