A drilling detection method and device of a PCB drilling machine, the drilling machine and a storage medium

Abstract

The application relates to a drilling detection method and device of a PCB drilling machine, a drilling machine and a storage medium, the method comprising the following steps: acquiring a to-be-drilled position coordinate of a PCB, acquiring a minimum interval between adjacent metal layers in a plurality of metal layers drilled by the to-be-drilled position coordinate; controlling a spindle module of the drilling machine to acquire a drill bit, the length of a drill head part of the drill bit is less than or equal to the minimum interval; controlling the drill bit to move to the to-be-drilled position and drill, when the drill head part contacts the metal layer, a drill head detection module outputs a first signal, when the drill head part is separated from the metal layer, the drill head detection module outputs a second signal, the application makes the drill bit more likely to form distinguishable contact and separation signal changes in the process of penetrating a previous metal layer and contacting a next metal layer, thereby improving the detection accuracy of signals of adjacent metal layers and improving the drilling detection effect under the condition of small layer intervals.

Description

Technical Field

[0001] This invention relates to the field of PCB processing technology, and in particular to a drilling detection method, apparatus, drilling machine, and storage medium for a PCB drilling machine. Background Technology

[0002] A PCB drilling machine is a device used in PCB manufacturing to drill holes in printed circuit boards. Drilling machines are equipped with drill bit detection modules, such as contact drill bit detection (CBD) systems, for real-time drill bit status monitoring and high-precision surface positioning. When the drill spindle encounters a metal surface during drilling, the CBD outputs a high voltage. After passing through the metal layer, the CBD returns to a low voltage. The control module uses this voltage change to determine the spindle's current position and calculate the distance between two metal layers. However, when two metal layers are too close, the CBD signal may not switch in time. After the drill bit passes through one metal layer, its tip immediately contacts the next metal layer, causing the signal acquisition for the second metal layer to fail. Summary of the Invention

[0003] To address the problem that existing PCB drilling machines, when the spacing between adjacent metal layers is small, often result in insignificant changes in the detection signal and difficulty in accurately identifying the position of adjacent metal layers due to the continuous contact of the sidewall with the previous metal layer during the process of the drill bit passing through the previous metal layer and contacting the next metal layer, this application provides a drilling detection method, device, drilling machine, and storage medium for a PCB drilling machine.

[0004] The embodiments of the present invention adopt the following technical solutions:

[0005] A drilling detection method for a PCB drilling machine, the drilling machine including a drill bit detection module and a drill bit electrically connected to the drill bit detection module, the drill bit including a drill head and a drill body connected to each other, the diameter of the drill head being larger than that of the drill body, the method comprising:

[0006] Obtain the coordinates of the hole to be drilled on the PCB, and obtain the minimum spacing between adjacent metal layers among several metal layers to be drilled corresponding to the hole location coordinates;

[0007] The spindle module of the drilling machine is controlled to acquire the drill bit, wherein the length of the drill head of the drill bit is less than or equal to the minimum spacing;

[0008] The drill bit is controlled to move to the position to be drilled and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

[0009] In some embodiments, obtaining the minimum spacing between adjacent metal layers among several drilled metal layers corresponding to the coordinates of the hole to be drilled specifically involves: obtaining pre-stored PCB layer structure data, extracting the interlayer spacing values ​​of all adjacent metal layers in the target drilling area from the data, and comparing them to obtain the minimum value, which is the minimum spacing.

[0010] In some embodiments, when obtaining the coordinates of the holes to be drilled on the PCB, the coordinates of all holes to be drilled are obtained, the minimum spacing of all holes to be drilled is calculated, and they are arranged in descending order, starting with the hole with the largest minimum spacing value and processed sequentially.

[0011] In some embodiments, the control module presets a threshold to divide holes with a minimum spacing greater than a set threshold into a first group of holes to be drilled, and the remaining holes into a second group of holes to be drilled. Each group of holes to be drilled corresponds to a type of drill bit. When processing the first group of holes to be drilled, the linear distance from the initial position of the spindle module to the coordinates of each hole in the group is calculated, and the hole with the closest distance is selected as the first drilling point. Subsequent holes to be drilled select the hole with the closest distance to the previous hole to minimize the idle travel time within the batch.

[0012] In some embodiments, the drill bit detection module is a CBD module. When the drill bit contacts the metal layer, the first signal is a high-level signal. When the drill bit leaves the metal layer, the second signal is a low-level signal. The length of the drill bit is ≤0.3mm, and the distance between the PCB surface layer and the reference layer is 0.3mm-0.8mm.

[0013] In some embodiments, a partition is provided between the drill bit and the drill body, the partition protruding from the drill bit surface. When the drill bit has completely entered a certain metal layer and the partition passes through the current metal layer, the drill bit detection module outputs a second signal.

[0014] In some embodiments, the drill bit includes an interconnected cutting edge and a guide portion, the guide portion being located at the distal end of the cutting edge.

[0015] A drilling detection device for a PCB drilling machine, comprising:

[0016] The acquisition unit is used to acquire the coordinates of the hole to be drilled on the PCB and to acquire the minimum spacing between adjacent metal layers among several drill-through metal layers corresponding to the coordinates of the hole to be drilled.

[0017] A drill bit matching unit is used to control the spindle module of the drilling machine to acquire a drill bit, wherein the length of the drill bit head is less than or equal to the minimum spacing.

[0018] The detection trigger unit is used to control the drill bit to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

[0019] A PCB drilling machine includes: a spindle module, a drill bit, a drill bit detection module, a storage module, and a control module. The drill bit includes a drill head and a drill body connected to each other. The diameter of the drill head is larger than the diameter of the drill body, and the outer helical side surface of the drill head is a continuous conductive surface. The axial length of the drill head is configured to be less than the minimum spacing between any adjacent metal layers at the drilling location of the PCB to be detected.

[0020] The spindle module is used to clamp and drive the drill bit to rotate and feed axially.

[0021] The drill bit detection module is electrically connected to the drill bit and is used to detect the contact state between the helical side of the drill bit and the metal layer and output a change signal.

[0022] The storage module is used to store PCB layer structure data;

[0023] The control module is connected to the spindle module, drill bit detection module, and storage module respectively, and is configured as follows:

[0024] Obtain the coordinates of the hole to be drilled on the PCB, and obtain the minimum spacing between adjacent metal layers among several metal layers to be drilled corresponding to the hole location coordinates;

[0025] The spindle module of the drilling machine is controlled to acquire the drill bit, wherein the length of the drill head of the drill bit is less than or equal to the minimum spacing;

[0026] The drill bit is controlled to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

[0027] A storage medium storing a computer program that, when executed by a processor, implements the aforementioned drilling detection method for a PCB drilling machine.

[0028] The present invention has the following main advantages:

[0029] This application matches the drill bit with a length less than or equal to the minimum spacing between adjacent metal layers at the drilling location. This makes it easier for the drill bit to form distinguishable contact and disengagement signal changes during the process of passing through the previous metal layer and contacting the next metal layer. This improves the detection accuracy of signals from adjacent metal layers, enhances the drilling detection effect under small layer spacing conditions, and helps improve the back-drilling stub control accuracy. Other advantages of the technical solution of this invention are described in specific embodiments. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a flowchart of a drilling detection method for a PCB drilling machine provided in an embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of the drill bit provided in an embodiment of the present invention.

[0033] Figure 3 This is a partial schematic diagram of the drill head and drill body of the drill bit provided in an embodiment of the present invention.

[0034] Figure 4 This is a schematic diagram of the drill bit drilling the same hole at times T1 to T4, as provided in the embodiment of the present invention.

[0035] Figure 5 This is an architectural diagram of the PCB drilling machine provided in an embodiment of the present invention.

[0036] In the attached diagram: 100, detection module; 200, drill bit; 210, drill head; 211, cutting edge; 212, guide section; 220, drill body section; 230, tool holder; 300, spindle module; 400, PCB; 410, hole to be drilled. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0038] In this embodiment, "several" and "more than" refer to two or more. In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "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 the 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 the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. For structural components such as drill bits, the terms "axial," "radial," and the reference system for directional descriptions are generally based on the rotational center axis of the drill bit. These are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component 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 application. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances and common knowledge.

[0040] This embodiment uses back-drilling of a PCB using a PCB drilling machine as an example. In high-speed and ultra-high-speed printed circuit boards, back-drilling is typically used to remove residual conductor segments in vias that are not involved in electrical connections, thereby reducing the adverse effects of via stubs on high-speed signal transmission. As signal rates continue to increase, industry requirements for controlling residual stubs after back-drilling are becoming increasingly stringent: in servers, storage, switching equipment, and high-frequency RF applications, the permissible range for residual stubs has been further compressed to smaller sizes. Therefore, the accuracy of back-drilling depth control has become one of the important factors affecting the manufacturing quality of high-speed boards.

[0041] To improve the accuracy of back-drilling depth control, optical or electrical methods are typically used to acquire the actual distance between the back-drilling surface layer and the target layer, thereby reducing the impact of PCB thickness errors after lamination on back-drilling control. When adjacent metal layers are close together, the spacing between the two metal layers is too small. After the drill bit passes through the previous metal layer, the control signal may not have time to switch before the tip contacts the next metal layer, resulting in signal acquisition failure for the subsequent metal layer. This makes it difficult to accurately obtain layer information, thus affecting the accuracy of back-drilling depth judgment.

[0042] <Example 1>

[0043] This embodiment provides a drilling detection method for a PCB drilling machine. Utilizing the correspondence between the drill bit geometry and the interlayer spacing within the board, the drill bit detection module outputs a recognizable signal when the drill bit contacts a metal layer. Furthermore, by limiting the drill bit length to less than the minimum spacing between adjacent metal layers that the target hole needs to penetrate, the possibility of the drill bit simultaneously crossing two metal layers between adjacent layers is reduced, thereby improving the stability of the identification at the contact moment of a single target metal layer. A PCB is a board structure comprising upper and lower CU layers (copper metal layers) and an intermediate PP layer (prepreg layer, i.e., insulating layer).

[0044] like Figure 2 , Figure 3 and Figure 5As shown, specifically, the drilling machine in this embodiment includes a drill bit detection module 100 and a drill bit 200 electrically connected to the drill bit detection module 100. The drill bit detection module 100 can be a CBD module, which can obtain a trigger signal by contacting and conducting with the drill bit 200 and the metal layer. When the drill bit contacts the metal layer, the circuit is turned on, causing the drill bit detection module 100 to output a high-level signal. When the drill bit 200 completely leaves the current metal layer, the circuit is turned off and the output returns to a low level. The control module can determine the position of the metal layer currently traversed by the drill bit by recognizing the transition of the level signal. The drill bit 200 is used to connect to the drilling machine spindle module 300 and completes the drilling of the PCB with the feed of the spindle module 300. At the same time, it can obtain the metal layer signal. The metal layer can be the copper layer or aluminum sheet, reference layer, target layer, etc. on the surface of the PCB 400. The drill bit 200 includes a drill head 210 and a drill body 220 connected to each other. The drill head 210 is located at the end of the drill bit 200 (i.e., the end away from the spindle module). The drill body 220 connects the drill head 210 to a smooth tool holder 230. The tool holder 230 is used by the spindle module 300 for gripping. The drill head 210 is used to first enter the PCB to be processed and contact the target metal layer. The function of the drill body 220 is chip removal; the chips generated during drilling are discharged through the drill body. In this embodiment, the drill head 210 and the drill body 220 are the working parts of the drill bit. The whole structure is helical and is ground from the same carbide bar. The outer helical side of the drill head is a continuous conductive surface. Since the entire drill bit is made of carbide, its entire surface is naturally conductive. Standard helical grooves 240 are distributed on this helical side for chip removal, but the top of the helical ridges still maintain continuous electrical contact capability. The drill head 210 in this embodiment includes a cutting edge 211 and a guide portion 212 connected to each other. The guide portion 212 is located at the distal end of the cutting edge 211, that is, at the end away from the spindle module. During drilling, the guide portion 212 contacts the PCB board first. The diameter D of the drill head 210 is larger than the diameter d of the drill body. When the drill bit drills, the drill head contacts the PCB board. After the drill head has completely passed through a certain metal layer, the drill body will not contact that metal layer, ensuring that the drill bit detection module can successfully complete the signal switching and avoiding false signal triggering.

[0045] The PCB drilling machine also includes a spindle module 300 and a control module. The spindle module 300 is used to acquire, clamp, and drive the drill bit to rotate and feed. The control module can cooperate with the spindle module 300 and the drill bit detection module 100 to perform hole position calling, drill bit selection, movement control, feed control, and signal acquisition. The control module can be an industrial computer, an embedded control unit, etc.

[0046] like Figures 1 to 5 As shown, the PCB drilling machine drilling detection method of this embodiment includes the following steps:

[0047] S100: Obtain the position coordinates of the hole 410 to be drilled on PCB 400, and obtain the minimum spacing between adjacent metal layers among several drilled metal layers corresponding to the position coordinates of the hole 410. The position coordinates of the hole 410 can be obtained using hole position data established before PCB processing. This hole position data records the planar position of the hole to be processed. The control module can retrieve the position coordinates of a target hole to be drilled from the drill tape and control the spindle module 300 or the worktable accordingly for alignment. The position coordinates of the hole to be drilled are the X and Y axis coordinates of the hole to be drilled, stored in the drilling machine control module, used to determine the drilling position. The drill bit drills down from this position, drilling downwards along the Z-axis direction (the axial direction of the spindle module). During back drilling, the drill bit 200 will drill through the corresponding metal layer and the dielectric layer between the metal layers. For example, the surface copper layer or aluminum sheet of the PCB, reference layer, etc. The minimum spacing between adjacent metal layers can be obtained according to the Gerber file of the circuit board. "Minimum spacing" refers to the minimum interlayer distance between any two adjacent metal layers in the Z-axis direction among several metal layers that need to be drilled at a certain coordinate position of the hole to be drilled. In this embodiment, the hole 410 to be drilled on PCB400 is a back-drilled hole. The PCB board has four metal layers, L1 to L4, and the drill bit drills from top to bottom. Figure 4 As shown, the position of the same drill head 210 on the PCB at times T1 to T4 for the same hole 410 to be drilled, where T1 < T2 < T3 < T4, meaning the drill head 210 continuously drills down.

[0048] S200: The spindle module 300 of the drilling machine acquires the drill bit 200, wherein the length H of the drill head 210 is less than or equal to the minimum spacing. The spindle module 300 is movable above the work platform, the drill bit is placed on the work platform, and the spindle module 300 moves to the corresponding drill bit position to acquire the drill bit. "Drill head length" can be understood as the axial length (UC length in the figure) of the drill bit tip forming an effective contact detection effect. According to the data obtained in step S100, the control module of the drilling machine controls the spindle module to automatically move to the required drill bit position and pick up the drill bit. In this step, the spindle module may select and load the corresponding drill bit from the tool magazine, clamping position, or pre-installed position, or the drill bit currently installed on the spindle may be directly put into use after being judged to meet the length condition. This application does not limit the specific form of the tool changing mechanism. Before drilling, the drill bit held by the spindle module should meet the requirement that the drill head length is less than or equal to the minimum spacing of the target hole position. In a preferred embodiment, to meet the back-drilling or controlled-depth drilling requirements of current mainstream high-density interconnect boards, the length of the drill head is ≤0.3mm, adapting to back-drilling scenarios where the spacing between the PCB surface layer and the reference layer is in the range of 0.3mm to 0.8mm. In this embodiment, the minimum spacing between the metal layers to be drilled 410 is the distance h1 between L1 and L2. Utilizing the structure where the drill head diameter D is larger than the drill body diameter, combined with the CBD detection principle, the signal ambiguity problem caused by continuous contact with the sidewalls when drilling through metal layers using traditional equal-diameter drill bits can be effectively avoided. Due to the smaller diameter of the drill body, a tiny gap is formed between the drill body and the hole wall after the drill head leaves the metal layer, thereby completely breaking the conductive contact and ensuring clear triggering of the second signal. This greatly improves the accuracy of detection when the drill tip penetrates each metal layer, effectively solving the technical problem of accurately controlling the stub length in the back-drilling process.

[0049] Preferably, when the drill bit length is less than the minimum spacing, the drill bit will only come into contact with the next metal layer after it has completely passed through the previous metal layer. At this time, the drill bit detection module has already completed the signal switching when the previous metal layer is passed through, so there will be no situation where the two signals overlap and cannot be distinguished, thus ensuring the accuracy of signal acquisition.

[0050] As another implementation, when the length of the drill bit is equal to the minimum spacing, it is theoretically possible to contact adjacent metal layers simultaneously. However, in reality, the upper and lower surfaces of the metal layers are not ideal parallel planes. The metal layers have surface roughness and burrs, the PCB board is warped, and the drill bit will wear out during use. Therefore, when selecting a new drill bit, if the length of the drill bit is equal to the theoretical minimum spacing, the drill bit can trigger signals sequentially during actual drilling, and the control module can also distinguish between the signals of the two metal layers.

[0051] S300: Control the drill bit to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal; when the drill bit leaves the metal layer, the drill bit detection module outputs a second signal. This step may include two processes: planar positioning and Z-axis feed. During planar positioning, the spindle module, the worktable, or both work together to align the drill bit center with the target drilling position coordinates. Then, the drilling action is performed, causing the drill bit to gradually approach and enter the PCB along the Z-axis. During drilling, the drill bit detection module continuously monitors the contact status between the drill bit and the conductive layer inside the PCB.

[0052] In this embodiment, the drill bit detection module uses a CBD module. When the drill bit contacts the metal layer L1, the first output signal is a high-voltage signal. The contact between the drill bit and the metal layer L1 can be either the tip or the sidewall of the drill bit, depending on the shape of the drill bit. When the drill bit detaches from the metal layer L1, the second output signal is a low-voltage signal. When the drill bit detaches from the metal layer, the sidewall of the drill bit is no longer in contact with the metal layer L1. After the control module receives the voltage signal transition, it can determine that the drill bit has completely passed through the current metal layer.

[0053] In this embodiment, because the drill bit length is pre-matched to be less than or equal to the minimum spacing of all adjacent metal layers, the drill bit will only contact the next metal layer L2 after it has completely detached from the previous metal layer L1 and completed the signal switching. This prevents the drill bit from simultaneously contacting two adjacent metal layers, thus avoiding a situation where the signal cannot be switched, and ensuring that the position of each metal layer can be accurately detected. By acquiring and analyzing this signal transition from high to low level, the control system can accurately determine the precise depth of the drill bit when entering and leaving each metal layer, thereby achieving high-precision control of the drilling depth.

[0054] Further, step S100 specifically includes: acquiring pre-stored PCB layer structure data, extracting the interlayer spacing values ​​of all adjacent metal layers in the target drilling area from the data, and comparing them to obtain the minimum value, which is the minimum spacing. The PCB layer structure data is stored in Gerber files. Gerber files are a standard file format used for printed circuit board (PCB) manufacturing (often translated as Gerber files or photoplotting files in Chinese). They are a collection of document formats used by PCB industry software to describe the images and drilling / milling data of circuit boards (circuit layers, solder mask layers, character layers, etc.). For a specific target drilling area, the control module extracts all relevant metal layers that will be drilled through the target hole from the pre-stored data, reads the interlayer spacing values ​​between adjacent metal layers, compares these interlayer spacings, and takes the minimum value as the minimum spacing corresponding to the coordinates of the hole to be drilled.

[0055] For example, when the borehole 410 needs to drill through the upper metal layer L1, the middle metal layer L2, and the lower metal layer L3 in sequence, the spacing value h1 between the upper metal layer L1 and the middle metal layer L2, and the spacing value h2 between the middle metal layer L2 and the lower metal layer L3 can be extracted respectively, and the two can be compared. The smaller one is determined as the minimum spacing. If there are more metal layers to be drilled through, all adjacent layer pairs can be traversed in the same way.

[0056] Preferably, in actual PCB production, a single circuit board often has thousands or even tens of thousands of holes requiring back-drilling. Each drilling location has a different minimum spacing between adjacent metal layers due to the different underlying layer stacking structures, and the drill bit's head length needs to be less than the corresponding minimum spacing. If the minimum spacing of all holes is not exactly the same, theoretically, any drill bit that meets the minimum spacing requirement can be selected. However, because a smaller drill bit length results in lower rigidity, it becomes difficult to drill through thick dielectric layers, easily leading to needle breakage and a decrease in overall efficiency. Furthermore, using a variety of drill bit specifications necessitates tool changes during processing, and frequent tool changes significantly reduce overall processing efficiency.

[0057] In step S100 of this embodiment, the position coordinates of all holes to be drilled are obtained, the minimum spacing of all holes to be drilled is calculated, and they are arranged in descending order, starting with the hole with the largest minimum spacing value for sequential processing. Specifically, when the control system obtains the position coordinates of all holes to be drilled on the PCB, drilling does not begin immediately; instead, a full data calculation is performed first. For each hole to be drilled, the system independently obtains the minimum spacing between adjacent metal layers in its corresponding drilling layers based on pre-stored PCB layer structure data. After calculation, the system builds a dataset of minimum spacing values ​​corresponding to all holes to be drilled and arranges them in descending order of value, thus generating a processing sequence from the hole with the largest minimum spacing value to the hole with the smallest minimum spacing value. At the start of processing, the spindle module prioritizes processing the hole at the beginning of the sequence, starting with the hole with the largest minimum spacing value for sequential drilling.

[0058] For example, the control module reads the coordinates (xi, yi) of all N holes to be drilled and their corresponding minimum spacing. It first selects the drill bit corresponding to the "minimum spacing" with the largest current value. Since the hole with the largest "minimum spacing" corresponds to a thicker medium layer, a longer drill bit can be used. The longer drill bit has better rigidity and smoother chip removal, allowing for higher spindle speed and feed rate, thereby shortening the single-hole machining time. In addition, the higher initial spindle speed and feed rate enable the drilling machine to reach thermal equilibrium faster, resulting in higher efficiency.

[0059] Preferably, the control module presets a threshold value, grouping holes with a minimum spacing greater than the set threshold into a first group of holes to be drilled, and the remaining holes into a second group. Each group of holes corresponds to a specific drill bit. When machining the first group of holes, the linear distance from the initial position of the spindle module to the coordinates of each hole in that group is calculated, and the hole with the closest distance is selected as the first drilling point. Subsequent holes to be drilled are selected from the holes closest to the previous hole to minimize the idle travel time within the batch. Specifically, the minimum spacing values ​​of all holes to be drilled are arranged from largest to smallest (h1, h2, h3, h4...hn). Holes with a minimum spacing value less than the threshold S are grouped together. For example, if the threshold S is 0.4mm, then holes with a minimum spacing value greater than or equal to 0.4mm are grouped into the first group of holes to be tested (h1, h2, h3...hx), and the second group of holes to be tested is (hx+1...hn).

[0060] This divides all holes to be drilled into two groups. The threshold S can be set according to the specifications of existing drill bits in the drill bit library and the "minimum spacing" value range of all holes to be tested. After grouping, the straight-line distance from the initial position of the spindle module to the coordinates of each hole in the first group is calculated. The initial position of the spindle module is the preset origin position. After calculating all the straight-line distances to the holes in the group, the closest hole is selected as the first drilling point. After each hole is drilled, the straight-line distance to all remaining un-drilled holes in the same group is calculated from the current drilling position. The next hole with the closest distance is selected for processing. Through this path optimization, the idle travel distance of the spindle module during the processing of the same group is minimized, unnecessary time loss is reduced, and the overall processing efficiency is improved. After all holes in the same group are processed, the drill bit adapted to the minimum spacing specification of the second group is replaced, and the processing of all holes in the second group is completed according to the same path planning logic. This ensures that the drill head length meets the accuracy requirements of each hole position, while keeping the number of tool changes to a minimum, thus balancing detection accuracy and processing efficiency.

[0061] Through the above technical solution, the two sets of holes to be drilled correspond to two different drill bits with different head lengths. All holes can be machined with only one tool change, avoiding frequent tool changes that reduce machining efficiency and ensuring that each hole is fitted with a drill bit that meets the length requirements, balancing machining accuracy and efficiency. The head length of each set of drill bits meets the length requirements of that set of holes. After machining all holes fitted with that drill bit, the drill bit is replaced with one fitted with the next smaller minimum spacing drill bit, and so on, until all holes are machined. Drill bits with longer head lengths and better rigidity are preferentially used to reduce the risk of drill bit breakage and ensure drilling efficiency and machining safety. Furthermore, the drilling machine's movement path can be optimized, reducing unnecessary energy consumption and time loss, further improving overall machining efficiency.

[0062] Preferably, the drill bit 200 has a partition 250, which is disposed between the drill head 210 and the drill body 220. The partition 250 is the dividing point where the diameters of the drill head and the drill body change; that is, the distance H between the partition 250 and the bottom of the drill body 220 is the length of the drill body. The partition 250 protrudes from the surface of the drill bit, and its size is smaller than the outer diameter of the drill head. When the drill head completely enters a certain metal layer and the partition passes through the current metal layer, the drill bit detection module outputs a second signal. The protruding partition clearly distinguishes the structural boundary between the drill head and the drill body, making it easier to control dimensional accuracy during drill bit manufacturing and reducing the processing difficulty of special drill bits.

[0063] <Example 2>

[0064] In this embodiment, the parts that are the same as in Embodiment 1 are given the same reference numerals, and the same text descriptions are omitted.

[0065] Compared to Embodiment 1, this embodiment provides a drilling detection device for a PCB drilling machine. This device can be understood as a collection of functional units that perform the aforementioned methods, and can be deployed in the main controller of the drilling machine in the form of software modules, hardware circuits, or firmware.

[0066] The PCB drilling machine's drilling detection device in this embodiment includes an acquisition unit, a drill bit matching unit, and a detection triggering unit. The acquisition unit acquires the coordinates of the PCB hole to be drilled and the minimum spacing between adjacent metal layers among several drill-through metal layers corresponding to the hole's coordinates. The drill bit matching unit is connected to the acquisition unit and the spindle module and controls the drilling machine's spindle module to acquire the drill bit, wherein the drill bit's head length is less than or equal to the minimum spacing. After acquiring the minimum spacing data, the drill bit matching unit selects the most suitable drill bit model from the tool magazine management database according to the matching rule that "the axial length of the drill head is less than or equal to the minimum spacing," and sends a control command to the drilling machine's spindle module to control it to perform a tool change action and grab the matched drill bit from the tool magazine. The detection triggering unit works in conjunction with the drill bit detection module and the control system to control the drill bit to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal; when the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

[0067] <Example 3>

[0068] In this embodiment, the parts that are the same as in Embodiment 1 and Embodiment 2 are given the same reference numerals, and the same text descriptions are omitted.

[0069] Compared to Embodiments 1 and 2, this embodiment provides a complete PCB drilling machine system architecture integrating the above-mentioned detection method and device. The PCB drilling machine includes: a spindle module, a drill bit, a drill bit detection module, a storage module, and a control module. The spindle module possesses high-frequency rotary drive capability and high-precision axial linear feed (Z-axis) capability, used to clamp and drive the drill bit to perform rotary cutting and axial feed movements. The specific structure of the drill bit is as described in Embodiment 1; its drill head diameter is larger than the drill body, and the outer helical side of the drill head is a continuous conductive surface to ensure continuous and stable contact detection and drilling chip removal. The axial length of the drill head is configured to be less than the minimum spacing between any adjacent metal layers of the PCB to be detected.

[0070] An electrical connection is established between the drill bit detection module and the drill bit. This module continuously detects the contact state between the helical side of the drill bit and the metal layers within the board, converting these state changes into high and low level signal outputs. A storage module, such as non-volatile memory or a solid-state drive, is used to store PCB layer structure data (Gerber files, etc.), processing programs, and operation logs.

[0071] The control module is a processing unit connected to the data buses of the spindle module, drill bit detection module, and storage module. The control module is configured to fully implement the aforementioned method during operation. Specifically, it first reads and parses the PCB layer data from the storage module to obtain the coordinates of the hole to be drilled and the corresponding minimum spacing between adjacent metal layers. Next, it calculates and sends a tool change command to the spindle module, instructing it to acquire a drill bit with a length less than or equal to this spacing. Finally, after rapid positioning, the control module coordinates the Z-axis feed with the spindle rotation and continuously monitors the input from the drill bit detection module. When the helical side of the drill bit contacts a metal layer, the drill bit detection module outputs a first signal, which is recorded by the control module. When the drill bit detaches from the metal layer, the drill bit detection module outputs a second signal, which the control module uses to monitor the depth position of the drill bit. Furthermore, the control module can also execute the sorting, grouping, and path planning procedures described in Embodiment 1.

[0072] <Example 4>

[0073] In this embodiment, the parts that are the same as in Embodiments 1 to 3 are given the same reference numerals, and the same text descriptions are omitted.

[0074] Compared to embodiments one to three, this embodiment provides a storage medium, such as a USB flash drive, optical disc, or hard disk. This storage medium stores computer program instructions. When the storage medium is installed or connected to the control system of a PCB drilling machine, and the computer program on it is retrieved and executed by the central processing unit of the control module, the processor guides the entire PCB drilling machine to operate according to the logic of the program code, thereby fully implementing all steps of the drilling and detection method for the PCB drilling machine as described in embodiment one.

[0075] In the above embodiments one to four, during the working process, depending on the different working environments, some of the technical implementation methods of embodiments one to five can be combined or replaced.

[0076] The technical principles of the present invention have been described above in conjunction with specific embodiments. However, it should be noted that these descriptions are merely for explaining the principles of the present invention and should not be construed as limiting the scope of protection of the present invention in any way. Based on this explanation, those skilled in the art can conceive of other specific embodiments or equivalent substitutions of the present invention without creative effort, and all such embodiments will fall within the scope of protection of the present invention.

Claims

1. A drilling detection method for a PCB drilling machine, characterized in that, The drilling machine includes a drill bit detection module and a drill bit electrically connected to the drill bit detection module. The drill bit includes a drill head and a drill body connected to each other. The diameter of the drill head is larger than that of the drill body. The method includes: Obtain the coordinates of the hole to be drilled on the PCB, and obtain the minimum spacing between adjacent metal layers among several metal layers to be drilled corresponding to the hole location coordinates; The spindle module of the drilling machine is controlled to acquire the drill bit, wherein the length of the drill head of the drill bit is less than or equal to the minimum spacing; The drill bit is controlled to move to the position to be drilled and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

2. The drilling detection method for a PCB drilling machine according to claim 1, characterized in that, The step of obtaining the minimum spacing between adjacent metal layers in the several drilled metal layers corresponding to the coordinates of the hole to be drilled is specifically as follows: obtain pre-stored PCB layer structure data, extract the interlayer spacing values ​​of all adjacent metal layers in the target drilling area from the data, and compare them to obtain the minimum value, which is the minimum spacing.

3. The drilling detection method for a PCB drilling machine according to claim 2, characterized in that, When obtaining the coordinates of the holes to be drilled on the PCB, obtain the coordinates of all holes to be drilled, calculate the minimum spacing of all holes to be drilled, sort them in descending order, and process them sequentially starting from the hole with the largest minimum spacing value.

4. The drilling detection method for a PCB drilling machine according to claim 3, characterized in that, The control module has a preset threshold. Holes with a minimum spacing greater than the set threshold are divided into the first group of holes to be drilled, and the remaining holes are divided into the second group of holes to be drilled. Each group of holes to be drilled corresponds to a type of drill bit. When machining the first group of holes to be drilled, the straight-line distance from the initial position of the spindle module to the coordinates of each hole in the group is calculated, and the hole with the closest distance is selected as the first drilling point. Subsequent holes to be drilled select the hole with the closest distance to the previous hole to minimize the idle travel time within the batch.

5. The drilling detection method for a PCB drilling machine according to claim 1, characterized in that, The drill bit detection module is a CBD module. When the drill bit contacts the metal layer, the first signal is a high-level signal. When the drill bit leaves the metal layer, the second signal is a low-level signal. The length of the drill bit is ≤0.3mm, and the distance between the PCB surface layer and the reference layer is 0.3mm-0.8mm.

6. The drilling detection method for a PCB drilling machine according to claim 1, characterized in that, A partition is provided between the drill bit and the drill body. The partition protrudes from the surface of the drill bit. When the drill bit has completely entered a certain metal layer and the partition passes through the current metal layer, the drill bit detection module outputs a second signal.

7. The drilling detection method for a PCB drilling machine according to claim 1, characterized in that, The drill bit includes an interconnected cutting edge and a guide portion, with the guide portion located at the distal end of the cutting edge.

8. A drilling detection device for a PCB drilling machine, characterized in that, include: The acquisition unit is used to acquire the coordinates of the hole to be drilled on the PCB and to acquire the minimum spacing between adjacent metal layers among several drill-through metal layers corresponding to the coordinates of the hole to be drilled. A drill bit matching unit is used to control the spindle module of the drilling machine to acquire a drill bit, wherein the length of the drill bit head is less than or equal to the minimum spacing. The detection trigger unit is used to control the drill bit to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

9. A PCB drilling machine, characterized in that, include: The system includes a spindle module, a drill bit, a drill bit detection module, a storage module, and a control module. The drill bit comprises a drill head and a drill body that are connected to each other. The diameter of the drill head is larger than the diameter of the drill body, and the outer helical side surface of the drill head is a continuous conductive surface. The axial length of the drill head is configured to be less than the minimum spacing between any adjacent metal layers at the drill hole location of the PCB to be detected. The spindle module is used to clamp and drive the drill bit to rotate and feed axially. The drill bit detection module is electrically connected to the drill bit and is used to detect the contact state between the helical side of the drill bit and the metal layer and output a change signal. The storage module is used to store PCB layer structure data; The control module is connected to the spindle module, drill bit detection module, and storage module respectively, and is configured as follows: Obtain the coordinates of the hole to be drilled on the PCB, and obtain the minimum spacing between adjacent metal layers among several metal layers to be drilled corresponding to the hole location coordinates; The spindle module of the drilling machine is controlled to acquire the drill bit, wherein the length of the drill head of the drill bit is less than or equal to the minimum spacing; The drill bit is controlled to move to the drilling position and drill down. When the drill bit contacts the metal layer, the drill bit detection module outputs a first signal. When the drill bit leaves the metal layer, the drill bit detection module outputs a second signal.

10. A storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the drilling detection method of the PCB drilling machine as described in any one of claims 1 to 7.

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