A PCB and slot preparation method thereof

Abstract

The present invention discloses a PCB and a method for preparing a slot therein. The method comprises the following steps: obtaining the thickness of the PCB to be drilled; determining, based on the thickness of the PCB to be drilled, the total number of drilling operations at the same location to be drilled on the PCB to be drilled, and the drill parameters of the slot drill used for each drilling operation; the drill parameters comprising the total blade length and effective blade length of the slot drill; the total blade length of the same slot drill being greater than or equal to the effective blade length; and controlling the slot drill to drill the PCB to be drilled based on the total number of drilling operations and the drill parameters to form the slot. The technical solution of the present invention utilizes slot drills with different drill parameters when drilling multiple holes at the same location to be drilled on the PCB to be drilled, wherein the total blade length of the slot drill is greater than or equal to the effective blade length. This facilitates chip removal during drilling and ensures uniform force on both sides of the slot drill during drilling, thereby enabling the production of slots with a 0.2 mm diameter and an aspect ratio of 40:1, thereby improving process capability.

Description

Technical Field

[0001] The present invention relates to the technical field of PCB preparation, and in particular to a PCB and a method for preparing a slot thereof. Background Art

[0002] With the development of high-speed communication products, the requirements for signal quality are getting higher and higher. Since vias have parasitic inductance, and the parasitic inductances of each via are in a parallel structure, the more vias there are, the smaller the parasitic inductance of the loop in the PCB, and thus the lower the high-frequency impedance. Therefore, by adding shielding slots near the signal holes, signal loss can be effectively reduced. At present, PCB (Printed Circuit Board) high-speed boards are usually designed with shielding slots to reduce signal loss. However, as the spacing between signal holes becomes denser, it is necessary to design slots with an aperture of less than or equal to 0.25mm to meet process requirements.

[0003] In the existing technology, mechanical drills can only process slots with a hole diameter greater than or equal to 0.4mm. For slots with a hole diameter less than 0.4mm, the required drill bit is relatively small in diameter, which is prone to needle breakage. In addition, the uneven force on both sides of the drilling hole causes the hole to be skewed, resulting in quality problems such as connecting ribs, and limiting the process capability. Summary of the Invention

[0004] The present invention provides a PCB and a method for preparing a slot thereof, so as to solve the problems existing in the prior art, realize the preparation of a slot with a 0.2 mm aperture and an aspect ratio of 40:1, and improve the process capability.

[0005] In a first aspect, the present invention provides a method for preparing a slot of a PCB, comprising:

[0006] Get the thickness of the PCB to be drilled;

[0007] Determining, based on the thickness of the PCB to be drilled, the total number of drilling operations n for the same location to be drilled on the PCB to be drilled, and the drill bit parameters of the slot drill bit used for each drilling operation; the drill bit parameters include the total blade length and effective blade length of the slot drill bit; the total blade length of the same slot drill bit is greater than or equal to the effective blade length;

[0008] According to the total number of drilling times n and the drill needle parameters, the slot drill is controlled to drill the PCB to be drilled to form the slot.

[0009] Optionally, determining the total number of times n to drill holes at the same location to be drilled on the PCB to be drilled, and the drilling parameters of the slot drill used for each drilling, based on the thickness of the PCB to be drilled, includes:

[0010] Determining, based on the thickness of the PCB to be drilled, the operable board thickness when drilling at the same drilling location on the PCB to be drilled;

[0011] According to the workable plate thickness and based on a first calculation formula, determining the total effective blade length of each slot drill bit for drilling the same position to be drilled;

[0012] Determining the total number of drilling times n according to the total effective blade length and the selectable effective blade length of the slot drill bit;

[0013] Determining the drilling parameters of the slot drill used for each drilling according to the total number of drilling times n;

[0014] The first calculation formula is: F = T / (1-h);

[0015] Wherein, F is the total effective blade length; T is the workable plate thickness; and h is the chip removal space.

[0016] Optionally, when the total number of drilling times n is greater than or equal to 2, the total blade length of the slot drill used for the i-th drilling is greater than the total blade length of the slot drill used for the i-1-th drilling; i is a positive integer greater than or equal to 2.

[0017] Optionally, controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes:

[0018] When the total number of drilling times n=1, a first slot drill is used to drill the PCB to be drilled; the effective blade length of the first slot drill is 1.5 mm.

[0019] Optionally, controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes:

[0020] When the total number of drilling times n=2, the first slot drill is used to drill the PCB to be drilled for the first drilling, and the second slot drill is used to drill the PCB to be drilled for the second drilling; the effective blade length of the first slot drill is 1.5 mm; the effective blade length of the second slot drill is 2.5 mm.

[0021] Optionally, controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes:

[0022] When the total number of drilling times n=p, the first slot drill is used to drill the PCB to be drilled for the first drilling, and the second slot drill is used to drill the PCB to be drilled for the second drilling; the third slot drill is used to drill the PCB to be drilled for the third and subsequent drilling times; the effective blade length of the first slot drill is 1.5 mm; the effective blade length of the third slot drill is 1 mm; and p is a positive integer greater than or equal to 3.

[0023] Optionally, controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes:

[0024] When the total number of drilling times n=p, during the first n / 2 drilling times, the slot drill is controlled to drill from the front side of the PCB to be drilled, and during the next n / 2 drilling times, the slot drill is controlled to drill from the back side of the PCB to be drilled;

[0025] When drilling from the front side of the PCB to be drilled, or when drilling from the back side of the PCB to be drilled, a first slotted hole drill is used to drill the PCB to be drilled for the first time, and a second slotted hole drill is used to drill the PCB to be drilled for the second time; and a third slotted hole drill is used to drill the PCB to be drilled for the third time and each subsequent time; the effective blade length of the first slotted hole drill bit is 1.5 mm; the effective blade length of the second slotted hole drill bit is 2.5 mm; and the effective blade length of the third slotted hole drill bit is 1 mm; and p is an even number greater than or equal to 5.

[0026] Optionally, the length of the slotted hole is greater than the diameter of the slotted hole drill bit;

[0027] Before controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters, the PCB slot preparation method further includes:

[0028] Obtain the length of the slot and the two end points of the slot in the length direction; the two end points are respectively the first hole to be drilled position and the second hole to be drilled position;

[0029] According to the two end point positions and the slot length, the other positions to be drilled between the two end point positions are marked in sequence using a dichotomy method.

[0030] Optionally, controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes:

[0031] According to the order of the positions to be drilled, the slotted hole drill is used to drill the positions to be drilled in sequence until the number of drilling times of each position to be drilled reaches the total number of drilling times n.

[0032] In a second aspect, the present invention provides a PCB, comprising a slot; the slot is prepared using any of the above-mentioned methods for preparing a slot of a PCB.

[0033] The technical solution of the present invention obtains the thickness of the PCB to be drilled, and determines the total number of drilling times to be performed at the same hole-to-be-drilled position of the PCB to be drilled, as well as the drill needle parameters of the slot drill used for each drilling, based on the thickness of the PCB to be drilled. Thus, based on the total number of drilling times and the drill needle parameters, the slot drill is controlled to drill the PCB to be drilled to form a slotted hole. When drilling, force is evenly applied to both sides of the slot drill needle to avoid hole deviation, thereby avoiding the problem of connecting ribs caused by hole deviation and improving process capability. In addition, by ensuring that the total blade length of the slot drill needle is greater than or equal to the effective blade length, chip removal is facilitated during drilling, making it less likely for the needle to break during drilling and improving the efficiency of slot hole preparation.

[0034] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 A flow chart of a method for preparing a slot hole in a PCB provided in an embodiment of the present invention;

[0037] Figure 2 A schematic structural diagram of a slotted hole drill provided by an embodiment of the present invention;

[0038] Figure 3 A flow chart of another method for preparing a slot hole in a PCB provided by an embodiment of the present invention;

[0039] Figure 4 A flow chart of another method for preparing a slot hole in a PCB provided in an embodiment of the present invention;

[0040] Figure 5 A schematic diagram of the sequence of positions to be drilled provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be practiced in an order other than that illustrated or described herein.

[0043] This embodiment provides a method for preparing slots in a PCB. Figure 1 A flowchart of a method for preparing a slot hole in a PCB according to an embodiment of the present invention is provided. Figure 1 As shown, the method for preparing the slot of the PCB includes:

[0044] S110: Obtain the thickness of the PCB to be drilled.

[0045] The PCB to be drilled may be, but is not limited to, a multilayer board, which may include a signal hole position and a slot hole position. The slot hole position is arranged near the signal hole position, and the slot hole is used to reduce the signal loss of the signal hole.

[0046] S120 , determining the total number of drilling times n at the same drilling location of the PCB to be drilled, and the drilling parameters of the slot drill used for each drilling according to the thickness of the PCB to be drilled.

[0047] Among them, the slot holes in the PCB are formed by drilling multiple circular holes in an overlapping manner. Therefore, when using a slot drill to drill a hole in the PCB to be drilled to form a slot hole, it is necessary to drill multiple positions to be drilled. However, when one side of a position to be drilled along the length direction of the slot hole has been drilled, and the other side has not been drilled, if the slot drill is controlled to drill the position to be drilled, it is easy to cause the hole to deviate due to uneven force on both sides of the slot drill needle. Therefore, according to the thickness of the PCB to be drilled, the slot drill can be controlled to drill at least once at the same position to be drilled in the PCB to be drilled to control the depth of each drilling. When drilling with a slot drill needle with each drill needle parameter, all positions to be drilled in the PCB to be drilled are drilled in sequence to avoid uneven force on both sides of the slot drill needle, thereby preventing the hole from deviating.

[0048] Figure 2 A schematic diagram of the structure of a slot drill provided by an embodiment of the present invention, referring to Figure 2 As shown, the drill parameters of the slotted hole drill include the total blade length L and the effective blade length L1 of the slotted hole drill. The effective blade length L1 can be the blade length of the slotted portion of the slotted hole drill. The drill parameters also include the unslotted blade length L2. The unslotted blade length L2 can be the blade length of the unslotted portion of the slotted hole drill. The total blade length L of the slotted hole drill is equal to the sum of the slotted blade length L1 and the unslotted blade length L2. The total blade length L of the same slotted hole drill is greater than or equal to the effective blade length L1. When the slotted hole drill is used for drilling, the chips formed can be guided through the slotted portion to the unslotted portion, causing the chips to break in the unslotted portion, thereby preventing chip blockage and avoiding chip removal blockage and needle breakage. Depending on the depth of the hole drilled at the same hole-to-be-drilled position of the PCB to be drilled, drills with different drill bit parameters can be used for drilling. In an exemplary embodiment, when the depth of the hole drilled is small, a slotted hole drill with a longer effective blade length L1 and a shorter total blade length L can be used for drilling, so that the depth of each drilling can be greater while ensuring smooth discharge of chips and no hole deviation, and it is beneficial to control the slotted hole drill for drilling; when the depth of the hole drilled is large, a slotted hole drill with a shorter effective blade length L1 and a longer total blade length L can be used for drilling, so that when drilling, at least part of the ungrooved portion of the slotted hole drill protrudes from the PCB to be drilled, which is beneficial to chip discharge and can prevent the PCB to be drilled from being damaged by the slotted hole drill. In addition, when the depth of the hole drilled is large, hole deviation is likely to occur. By using a slotted hole drill with a shorter effective blade length for drilling, the uneven force on both sides of the hole-to-be-drilled position can be reduced, which is beneficial to preventing hole deviation.

[0049] S130 , controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill needle parameters to form a slot.

[0050] Specifically, after obtaining the thickness of the PCB to be drilled, the total number of drilling times n to be performed at the same hole-to-be-drilled position of the PCB to be drilled and the drill bit parameters of the slot drill used for each drilling are determined based on the thickness of the PCB to be drilled. Then, based on the total number of drilling times n and the drill bit parameters, the slot drill with corresponding slot parameters is controlled to drill the PCB to be drilled until the last drilling of all hole-to-be-drilled positions of the PCB to be drilled is completed, thereby forming slot holes.

[0051] In this embodiment, the thickness of the PCB to be drilled is obtained, and the total number of drilling times to be performed at the same hole-to-be-drilled position of the PCB to be drilled, as well as the drill parameters of the slot drill used for each drilling, are determined based on the thickness of the PCB to be drilled. Thus, based on the total number of drilling times and the drill parameters, the slot drill is controlled to drill the PCB to be drilled to form a slotted hole. When drilling, force is evenly applied to both sides of the slot drill to avoid hole deviation, thereby avoiding the problem of connecting ribs caused by hole deviation and improving the process capability. In addition, by making the total blade length of the slot drill greater than or equal to the effective blade length, chip removal is facilitated during drilling, making it less likely that the drill will break during drilling, thereby improving the efficiency of slot preparation.

[0052] In an optional embodiment, when the total number of drilling times n is greater than or equal to 2, the total blade length of the slot drill used in the i-th drilling is greater than the total blade length of the slot drill used in the i-1th drilling. Here, i is a positive integer greater than or equal to 2. For example, when the total number of drilling times n=3 is determined, since the depth of the hole drilled in the third drilling time is greater than the depth of the second drilling time, the total blade length of the slot drill used in the third drilling time can be set to be greater than the total blade length of the slot drill used in the second drilling time, so that during each drilling operation, a portion of the blade length of the slot drill used protrudes from the PCB to be drilled, thereby preventing the PCB to be drilled from being damaged by the slot drill.

[0053] Optional, Figure 3 A flowchart of another method for preparing a slot hole in a PCB according to an embodiment of the present invention is provided. Figure 3 As shown, according to the thickness of the PCB to be drilled, the total number of drilling times n at the same drilling position of the PCB to be drilled is determined, and the drilling parameters of the slot drill used for each drilling include:

[0054] S121. Determine, based on the thickness of the PCB to be drilled, the workable board thickness when drilling at the same drilling position of the PCB to be drilled.

[0055] Multiple workable board thicknesses can be determined based on the drill bit parameters of the selectable slot drill bit. Based on the thickness of the PCB to be drilled, a workable board thickness equal to the thickness of the PCB to be drilled, or a minimum workable board thickness greater than the thickness of the PCB to be drilled, is determined as the workable board thickness when drilling at the same drilling location on the PCB to be drilled.

[0056] S122. Determine the total effective blade length of each slot drill bit for drilling the same hole to be drilled based on the first calculation formula according to the operable plate thickness.

[0057] The first calculation formula is: F = T / (1-h), where F is the total effective blade length, T is the workable plate thickness, and h is the chip clearance. The chip clearance is the chip clearance space for each slot drill bit. In one exemplary embodiment, the chip clearance h = 10%.

[0058] It is understandable that when drilling a hole in a PCB to be drilled, the surface of the PCB to be drilled that is close to the slot drill needle is covered with a cover plate, and the surface of the PCB to be drilled that is away from the slot drill needle is provided with a pad. When drilling, the slot drill needle needs to first drill the cover plate, then drill the PCB to be drilled, and finally drill the pad. When the drilling depth of the pad is constant, for example, when the drilling depth of the pad is 0.4 mm, a slot is formed in the PCB to be drilled. Therefore, in this embodiment, when calculating the sum of the effective blade lengths of each slot drill needle drilling the same hole position to be drilled, the thickness of the cover plate and the drilling depth of the pad plate can also be considered. In this case, it can be determined based on the second calculation formula; the second calculation formula is: F = T / (1-h)-D1-D2; where F is the sum of the effective blade lengths; T is the workable board thickness; h is the chip removal space; D1 is the cover plate thickness; and D2 is the drilling depth of the pad.

[0059] S123. Determine the total number of drilling times n according to the total effective blade length and the effective blade length of the selectable slot drill bit.

[0060] The selectable effective blade length of the slotted hole drill can be related to the slotted hole diameter, the accuracy of the slotted hole diameter, and the depth of the drilled hole. The smaller the effective blade length of the slotted hole drill, the less likely it is to cause hole deviation when drilling with the slotted hole drill. Conversely, the larger the effective blade length of the slotted hole drill, the more likely it is to cause uneven force on both sides of the slotted hole drill during drilling, which is more likely to cause hole deviation. Therefore, the smaller the slotted hole diameter, the higher the accuracy of the slotted hole diameter, and the greater the depth of the drilled hole, the shorter the effective blade length of the slotted hole drill, making it less likely to cause hole deviation. In an optional embodiment, the selectable effective blade lengths may include 1.5mm, 2.5mm, and 1mm. When the effective blade length is 1.5mm, the total blade length can be 1.5mm; when the effective blade length is 2.5mm, the total blade length can be 3mm; when the effective blade length is 1mm, the total blade length can be 4mm, 5mm, or 5.5mm.

[0061] S124. Determine the drilling parameters of the slot drill used for each drilling according to the total number of drilling times n.

[0062] In an optional embodiment, taking the selectable effective blade lengths including 1.5 mm, 2.5 mm and 1 mm as an example, when drilling the PCB to be drilled for the first time, the effective blade length of the slot drill bit used can be 1.5 mm, when drilling the same position of the PCB to be drilled for the second time, the effective blade length of the slot drill bit used can be 2.5 mm, when drilling the same position of the PCB to be drilled for the third time, the effective blade length of the slot drill bit used can be 1 mm, and when drilling the same position of the PCB to be drilled for the fourth time and thereafter, the effective blade length of the slot drill bit used can be 1 mm.

[0063] Specifically, after obtaining the thickness of the PCB to be drilled, the operable board thickness when drilling at the same hole-to-be-drilled position of the PCB to be drilled is determined based on the thickness of the PCB to be drilled, and the sum of the effective blade lengths of the slot drill bits for drilling the same hole-to-be-drilled position is determined based on the operable board thickness and the first calculation formula, thereby determining the total number of drilling times n based on the sum of the effective blade lengths and the effective blade lengths of the selectable slot drill bits, and then determining the drill bit parameters of the slot drill bit used for each drilling based on the total number of drilling times n, thereby controlling the slot drill bit to drill the PCB to be drilled based on the total number of drilling times n and the drill bit parameters to form a slot hole.

[0064] Optionally, according to the total number of drilling times n and the drill bit parameters, controlling the slot drill to drill the PCB to be drilled includes: when the total number of drilling times n=1, using the first slot drill to drill the PCB to be drilled; the effective blade length of the first slot drill bit is 1.5 mm.

[0065] Optionally, controlling the slot drill to drill the PCB to be drilled based on the total number of drilling times n and the drill bit parameters may also include: when the total number of drilling times n=2, using the first slot drill to drill the PCB to be drilled for the first time, and using the second slot drill to drill the PCB to be drilled for the second time; the effective blade length of the first slot drill bit is 1.5 mm; the effective blade length of the second slot drill bit is 2.5 mm.

[0066] The drilling depth H1 of the first slot drill can be determined based on the effective blade length of the first slot drill, the cover plate thickness, and the chip removal space. For example, H1 = (F1 - D1) * (1 - h), where F1 is the effective blade length of the first slot drill, D1 is the cover plate thickness, and h is the chip removal space. During the second drilling, the hole location in the PCB to be drilled is drilled through. The cover plate can be omitted during the second drilling, thereby facilitating chip removal by the slot drill.

[0067] Optionally, controlling the slot drill to drill the PCB to be drilled based on the total number of drilling times n and the drill bit parameters may also include: when the total number of drilling times n=p, using the first slot drill to drill the PCB to be drilled for the first time, and using the second slot drill to drill the PCB to be drilled for the second time; using the third slot drill to drill the PCB to be drilled for the third time and each subsequent drilling; the effective blade length of the first slot drill bit is 1.5 mm; the effective blade length of the second slot drill bit is 2.5 mm; and the effective blade length of the third slot drill bit is 1 mm.

[0068] Where p is a positive integer greater than or equal to 3. The drilling depth H1 of the first slotted hole drill can be determined based on the effective blade length of the first slotted hole drill, the thickness of the cover plate, and the chip removal space. For example, H1 = (F1-D1)*(1-h). The drilling depth H2 of the second slotted hole drill can be determined based on the effective blade length of the second slotted hole drill and the chip removal space. For example, H2 = F2*(1-h). The drilling depth of the third slotted hole drill can be determined based on the effective blade length of the third slotted hole drill and the chip removal space. For example, H3 = F3*(1-h). During the final drilling operation, the hole to be drilled in the PCB is drilled through. Where D1 is the cover plate thickness, and h is the chip removal space. During the second and subsequent drilling operations, the cover plate can be omitted to facilitate chip removal by the slotted hole drill.

[0069] Optionally, based on the total number of drilling times n and the drill bit parameters, controlling the slot hole drill to drill holes in the PCB to be drilled may also include: when the total number of drilling times n=p, controlling the slot hole drill to drill from the front side of the PCB to be drilled during the first n / 2 drilling times, and controlling the slot hole drill to drill from the back side of the PCB to be drilled during the next n / 2 drilling times; when drilling from the front side of the PCB to be drilled, or when drilling from the back side of the PCB to be drilled, using the first slot hole drill to drill the PCB to be drilled during the first drilling, and using the second slot hole drill to drill the PCB to be drilled during the second drilling; using the third slot hole drill to drill the PCB to be drilled during the third drilling and each drilling thereafter; the effective blade length of the first slot hole drill is 1.5 mm; the effective blade length of the second slot hole drill is 2.5 mm; and the effective blade length of the third slot hole drill is 1 mm.

[0070] Here, p is an even number greater than or equal to 5.

[0071] Specifically, when the thickness of the PCB to be drilled is relatively large and the total number of drilling times n=p is determined, where p is an even number greater than or equal to 5, the slot drill can be controlled to drill n / 2 times from the front side of the PCB to be drilled and n / 2 times from the back side of the PCB to be drilled to form the slot, thereby reducing uneven force on both sides of the slot drill and preventing hole deviation.

[0072] In an optional embodiment, when the thickness of the PCB to be drilled is greater than 4.5 mm, the total number of drillings n = p can be determined, thereby controlling the slot drill to drill n / 2 times from the front side of the PCB to be drilled and n / 2 times from the back side of the PCB to be drilled. In this case, the slot drill can be mounted on a drilling machine with a CCD function to improve the alignment accuracy of the front and back drilling when preparing the slots, thereby improving the accuracy of the prepared slots. In this embodiment, during drilling, X-ray can be used to first drill the positioning holes for the slot drill. For example, a drill with a diameter of 1.6 mm can be used to drill the positioning holes at the front side of the PCB to be drilled, and then a drill with a diameter of 1.6 mm can be used to drill the positioning holes at the back side of the PCB to be drilled to form the positioning holes. After forming the positioning holes, a positioning pin with a diameter of 1.575 mm can be used to verify the accuracy of the positioning holes to ensure that the vertical alignment of the positioning holes is within 0.025 mm, thereby ensuring the accuracy of the slots. A CCD-enabled drilling machine is then used to drill holes n / 2 times from the front side of the PCB to be drilled, respectively, to complete 55% of the slot hole depth in the PCB to be drilled, and n / 2 times from the back side of the PCB to be drilled, to form the slot hole. Before drilling, the third formula can be used to determine the total effective blade lengths of the slot drills used to drill the same hole location from the front or back side. Based on the total effective blade lengths and the effective blade lengths of the selectable slot drills, the total number of front drilling times (n / 2) or back drilling times (n / 2) is determined. Furthermore, based on the total number of drilling times, the drill parameters of the slot drill used for each drilling operation are determined. Based on the total number of front and back drilling times, as well as the drill parameters, the slot drill is controlled to drill the PCB to form the slot hole.

[0073] Optional, Figure 4 A flowchart of another method for preparing a slot hole in a PCB according to an embodiment of the present invention is provided. Figure 4 As shown, before controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill needle parameters, the PCB slot preparation method further includes:

[0074] S1201, obtaining the length of the slot and the two end points of the slot in the length direction; the two end points are respectively the first position to be drilled and the second position to be drilled.

[0075] The length of the slot hole is greater than the diameter of the slot hole drill. Therefore, it is necessary to control each slot hole drill to drill multiple positions to be drilled in sequence, thereby forming the slot hole.

[0076] S1202: Based on the two endpoint positions and the slot length, the other positions to be drilled between the two endpoint positions are sequentially marked using a binary method.

[0077] Specifically, the length of the slot and the positions of its two endpoints along the length are determined. Based on the two endpoints and the slot length, the two endpoints are designated as the first and second positions to be drilled, respectively. A binary search method is then used to sequentially mark the remaining positions to be drilled between the two endpoints. After drilling each position to be drilled, the slot is formed. In an optional embodiment, the distance between the centers of two adjacent positions to be drilled is less than or equal to 0.05 mm.

[0078] In an exemplary embodiment, Figure 5 A schematic diagram of the sequence of positions to be drilled provided by an embodiment of the present invention, with reference to Figure 5 As shown, one end of the slot hole in the length direction is the first hole position to be drilled, and the other end is the second hole position to be drilled. The dichotomy method is used to determine the middle position between the first hole position to be drilled and the second hole position to be drilled as the third hole position to be drilled, the middle position between the first hole position to be drilled and the third hole position to be drilled is determined as the fourth hole position to be drilled, the middle position between the third hole position to be drilled and the second hole position to be drilled is determined as the fifth hole position to be drilled, and so on, until the middle position between the first hole position to be drilled and the sixth hole position to be drilled is determined as the tenth hole position to be drilled, and the distance between the centers of the first hole position to be drilled and the tenth hole position to be drilled is less than 0.05 mm.

[0079] Continue to refer Figure 4 As shown, in this embodiment, according to the total number of drilling times n and the drill bit parameters, the slot drill is controlled to drill the PCB to be drilled, including:

[0080] S131 , according to the order of the positions to be drilled, use a slotted drill bit to drill the positions to be drilled in sequence until the number of drilling times of each position to be drilled reaches the total number of drilling times n.

[0081] Specifically, the binary method is used to mark the other positions to be drilled between the two endpoint positions in sequence. After that, all the positions to be drilled and the drilling order of each position to be drilled are determined. According to the order of each position to be drilled, a slot drill is used to drill each position to be drilled in sequence until the number of drilling times of each position to be drilled reaches the total number of drilling times, thereby forming a slot hole.

[0082] In an exemplary embodiment, taking the total number of drilling times n as 3 times as an example, after determining the drilling order of each position to be drilled, the first slotted hole drill is used to drill each position to be drilled in turn during the first drilling, the second slotted hole drill is used to drill each position to be drilled in turn during the second drilling, and the third slotted hole drill is used to drill each position to be drilled in turn during the third drilling, until the number of drilling times for each position to be drilled reaches 3 times.

[0083] Based on the same inventive concept, this embodiment further provides a PCB including a slot; the slot is produced using the PCB slot production method provided in any of the aforementioned embodiments. Because the PCB provided in this embodiment is produced using the PCB slot production method provided in any of the aforementioned embodiments, it can achieve the beneficial effects of the PCB slot production method provided in any of the aforementioned embodiments. Similarities can be found in the aforementioned description.

[0084] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for preparing a slot of a PCB, characterized in that: include: Get the thickness of the PCB to be drilled; Determining, based on the thickness of the PCB to be drilled, the total number of drilling operations n for the same location to be drilled on the PCB to be drilled, and the drill bit parameters of the slot drill bit used for each drilling operation; the drill bit parameters include the total blade length and effective blade length of the slot drill bit; the total blade length of the same slot drill bit is greater than or equal to the effective blade length; The total number of drilling times n at the same drilling location on the PCB to be drilled, and the drilling parameters of the slot drill used for each drilling, are determined based on the thickness of the PCB to be drilled, including: Determining, based on the thickness of the PCB to be drilled, a workable board thickness when drilling at the same location to be drilled on the PCB to be drilled; wherein a workable board thickness equal to the thickness of the PCB to be drilled or a minimum workable board thickness greater than the thickness of the PCB to be drilled is determined as the workable board thickness when drilling at the same location to be drilled on the PCB to be drilled; According to the workable plate thickness and based on a first calculation formula, determining the total effective blade length of each slot drill bit for drilling the same position to be drilled; Determining the total number of drilling times n according to the total effective blade length and the selectable effective blade length of the slot drill bit; Determine the drill bit parameters of the slotted hole drill bit used for each drilling according to the total number of drilling times n; wherein, when the drilled hole depth is small, a slotted hole drill bit with a longer effective blade length L1 and a shorter total blade length L is used for drilling; and when the drilled hole depth is large, a slotted hole drill bit with a shorter effective blade length L1 and a longer total blade length L is used for drilling; The first calculation formula is: F=T / (1-h); Wherein, F is the total effective blade length; T is the workable plate thickness; h is the chip removal space; According to the total number of drilling times n and the drill needle parameters, the slot drill is controlled to drill the PCB to be drilled to form the slot.

2. The method for preparing a slot of a PCB according to claim 1, wherein: When the total number of drilling times n is greater than or equal to 2, the total blade length of the slot drill used for the i-th drilling is greater than the total blade length of the slot drill used for the i-1-th drilling; i is a positive integer greater than or equal to 2.

3. The method for preparing a slot of a PCB according to claim 1, wherein: Controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes: When the total number of drilling times n=1, a first slot drill is used to drill the PCB to be drilled; the effective blade length of the first slot drill is 1.5 mm.

4. The method for preparing a slot of a PCB according to claim 1, wherein: Controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes: When the total number of drilling times n=2, the first slot drill is used to drill the PCB to be drilled for the first drilling, and the second slot drill is used to drill the PCB to be drilled for the second drilling; the effective blade length of the first slot drill is 1.5 mm; the effective blade length of the second slot drill is 2.5 mm.

5. The method for preparing a slot of a PCB according to claim 1, wherein: Controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes: When the total number of drilling times n=p, the first slot drill is used to drill the PCB to be drilled for the first drilling, and the second slot drill is used to drill the PCB to be drilled for the second drilling; the third slot drill is used to drill the PCB to be drilled for the third and subsequent drilling times; the effective blade length of the first slot drill is 1.5 mm; the effective blade length of the third slot drill is 1 mm; and p is a positive integer greater than or equal to 3.

6. The method for preparing a slot of a PCB according to claim 1, wherein: Controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes: When the total number of drilling times n=p, during the first n / 2 drilling times, the slot drill is controlled to drill from the front side of the PCB to be drilled, and during the next n / 2 drilling times, the slot drill is controlled to drill from the back side of the PCB to be drilled; When drilling from the front side of the PCB to be drilled, or when drilling from the back side of the PCB to be drilled, a first slotted hole drill is used to drill the PCB to be drilled for the first time, and a second slotted hole drill is used to drill the PCB to be drilled for the second time; and a third slotted hole drill is used to drill the PCB to be drilled for the third time and each subsequent time; the effective blade length of the first slotted hole drill bit is 1.5 mm; the effective blade length of the second slotted hole drill bit is 2.5 mm; and the effective blade length of the third slotted hole drill bit is 1 mm; and p is an even number greater than 5.

7. The method for preparing a slot of a PCB according to claim 1, wherein: The length of the slotted hole is greater than the diameter of the slotted hole drill bit; Before controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters, the PCB slot preparation method further includes: Obtain the length of the slot and the two end points of the slot in the length direction; the two end points are respectively the first hole to be drilled position and the second hole to be drilled position; According to the two end point positions and the slot length, the other positions to be drilled between the two end point positions are marked in sequence using a dichotomy method.

8. The method for preparing a slot of a PCB according to claim 7, wherein: Controlling the slot drill to drill the PCB to be drilled according to the total number of drilling times n and the drill bit parameters includes: According to the order of the positions to be drilled, the slotted hole drill is used to drill the positions to be drilled in sequence until the number of drilling times of each position to be drilled reaches the total number of drilling times n.

9. A PCB, characterized in that: The PCB includes a slot; the slot is prepared using the method for preparing a slot of a PCB according to any one of claims 1 to 8.

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