A circuit board edge milling device and process method

Abstract

This application relates to the field of circuit board processing, in particular to a circuit board edge milling device and a process method, including a base, a loading table, and a fixture: installed on the loading table and used to clamp the circuit board to be processed; a milling cutter head: used to mill the edge of the circuit board; a driving component: including a milling mechanism for driving the milling cutter head to rotate, a feeding mechanism for driving the milling cutter head to translate in both forward and reverse directions along the surface to be processed of the circuit board, and an adjusting mechanism for adjusting the milling allowance of the milling cutter head. Two milling cutter heads are provided to perform forward and reverse milling on the surface to be processed of the circuit board, thereby reducing the length of the curled edge and meeting the processing requirements of the circuit board.

Description

Technical Field

[0001] The present application relates to the field of circuit board processing, and particularly relates to a circuit board edge milling and cutting device and a process method thereof. Background Art

[0002] A PCB circuit board, also known as a printed circuit board, a printed wiring board, or a printed circuit board, is an important electronic component, a support for electronic components, and a provider of electrical connections for electronic components; in the production process of the circuit board, it involves blanking and edge grinding, drilling, outer layer pattern, gold plating, etching, inspection, silk screen solder mask, hot air leveling, silk screen characters, shape processing, and test inspection. Generally, the surface of the circuit board is also polished.

[0003] Generally, grooves are processed on the edge of the circuit board. During the grinding and milling process of the circuit board edge, when the milling cutter first passes through the groove opening, the part of the groove opening will be rolled and milled into the groove, forming a curled edge, while the other groove opening on the other side of the groove will not form a curled edge, resulting in an uneven groove opening, which affects the use of the groove and also reduces the production quality of the circuit board. Summary of the Invention

[0004] In order to alleviate the problem that the part of the groove opening where the milling cutter first passes is rolled and milled into the groove during milling and grinding, the present application provides a circuit board edge milling and cutting device and a process method thereof.

[0005] A circuit board edge milling and cutting device provided by the present application adopts the following technical solutions:

[0006] A circuit board edge milling and cutting device includes a base, a loading table, and further includes: a fixture: installed on the loading table and used to clamp the circuit board to be processed; a milling cutter head: used to mill the edge of the circuit board; a driving assembly: including a milling mechanism for driving the milling cutter head to rotate, a feeding mechanism for driving the milling cutter head to translate in both forward and reverse directions along the surface to be processed of the circuit board, and an adjusting mechanism for adjusting the milling allowance of the milling cutter head.

[0007] By adopting the above technical solutions, a feeding mechanism is provided in the driving assembly to drive the milling cutter head to translate in both forward and reverse directions along the surface to be processed, so that when milling in the reverse direction, the curled edge generated during forward milling can be milled off. An adjusting mechanism for adjusting the milling allowance is also provided. By reducing the milling allowance during reverse milling, the length of the curled edge during reverse milling can be reduced. Under the condition of meeting the milling and cutting processing requirements, the curled edge can be further reduced through multiple forward and reverse milling operations until the processing requirements are met.

[0008] Further preferably, the fixture includes a positioning column slidably installed on the loading table and a pressing plate for pressing the circuit board. The end surface on the side opposite to the surface to be processed abuts against the positioning column. The positioning column is parallel to the feeding mechanism, and the feeding mechanism is arranged on the base.

[0009] By adopting the above technical solution, the positioning posts are parallel to the feeding mechanism, and the end face on the opposite side of the surface to be processed of the circuit board abuts against the positioning posts, so that the surface to be processed of the circuit board is parallel to the feeding direction of the feeding mechanism, thereby enabling the milling cutter head to mill along the surface to be processed, ensuring the flatness of the surface to be processed. After the pressing plate presses the circuit board, the positioning posts slide towards the side close to the milling cutter head, and then push the circuit board to move closer to the milling cutter head, making the surface to be processed of the circuit board flush with the rotation center line of the milling cutter head. At this time, the milling allowance of the surface to be processed of the circuit board is the largest, which is also convenient for the adjusting mechanism to adjust the milling allowance.

[0010] Further preferably, the adjusting mechanism includes a rotating box for installing the milling cutter head, and a first driving member installed on the feeding mechanism and driving the rotating box to rotate. The output end of the first driving member is fixedly connected to the rotating box, and the milling cutter head is eccentrically arranged with respect to the output end of the first driving member.

[0011] By adopting the above technical solution, the first driving member drives the rotating box to rotate, thereby driving the milling cutter head to rotate around the output end of the first driving member, adjusting the distance between the milling cutter head and the surface to be processed of the circuit board, and thus changing the milling allowance of the milling cutter head for processing the circuit board.

[0012] Further preferably, an angle detection mechanism is provided between the first driving member and the rotating box.

[0013] By adopting the above technical solution, the angle detection mechanism is provided to detect the rotation angle of the rotating box, that is, to detect the rotation angle of the milling cutter head around the output end of the first driving member, so as to facilitate calculating the distance between the milling cutter head and the surface to be processed of the circuit board, and thus calculating the milling allowance of the milling cutter head.

[0014] Further preferably, the rotation angle range of the rotating box is: 0° to 180°.

[0015] By adopting the above technical solution, the rotation angle range of the rotating box is limited between 0° and 180°, that is, the rotation angle of the milling cutter head around the output end of the first driving member is between 0° and 180°, so that the distance between the milling cutter head and the surface to be processed of the circuit board corresponds one-to-one to the rotation angle of the rotating box.

[0016] Further preferably, two milling cutter heads are provided and symmetrically arranged with respect to the output end of the first driving member.

[0017] By adopting the above technical solution, the two milling cutter heads are symmetrically arranged with respect to the center of the output end of the first driving member. That is, by driving the rotating box to rotate through the adjusting mechanism, not only can the milling allowance of the milling cutter head be adjusted, but also the use of the milling cutter head can be switched, which is convenient for replacement.

[0018] Further preferably, the milling mechanism is arranged on the rotating box and includes a second driving member and a transmission mechanism. The transmission mechanism includes two ratchet transmissions with opposite meshing directions. Each ratchet transmission includes a ratchet wheel and a ratchet gear. Both ratchet wheels are connected to the output end of the second driving member, and two milling heads are respectively connected to the two ratchet gears through rotating shafts. The blades of the two milling heads face in opposite directions.

[0019] By adopting the above technical solution, ratchet transmissions are arranged between the second driving member and the two milling heads, and the two ratchet transmissions have opposite meshing directions, that is, the second driving member does not drive the two milling heads to rotate simultaneously, saving electric energy; and the two milling heads rotate in opposite directions and the blades face in opposite directions, so the two milling heads respectively perform forward and reverse translational milling on the surface of the circuit board to be processed, making the milling lines on the surface to be processed the same, facilitating subsequent polishing, and also capable of cutting off the curled edges generated by the previous milling.

[0020] Further preferably, a synchronous belt assembly is connected between the ratchet gear and the milling head.

[0021] By adopting the above technical solution, the synchronous belt assembly is not only used for power transmission between the ratchet mechanism and the milling head, but also can increase the distance between the two milling heads, avoid waste chips from splashing onto the other milling head, and improve the safety when replacing the milling head.

[0022] The present application also provides a process method for applying a circuit board edge milling device, and its process steps include:

[0023] Loading: Place the circuit board on the loading table, abut the end face on the side opposite to the surface to be processed against the positioning column, and press the circuit board tightly with a pressing plate;

[0024] First adjustment: Start the first driving member to drive the rotating box to rotate, and adjust the machining allowance of one of the milling heads for the circuit board;

[0025] Rotation: Start the second driving member, and through the ratchet transmission and the synchronous belt assembly transmission, realize the rotation of the milling head for milling, and at this time the other milling head does not rotate;

[0026] First milling: Start the feeding mechanism, thereby driving the adjustment mechanism, the milling mechanism and the milling head to feed synchronously, and mill the surface of the circuit board to be processed;

[0027] Second adjustment: After the first milling is completed, start the first driving member, drive the rotating box to rotate and make the other milling head rotate to the milling position, and adjust the machining allowance of this milling head for the circuit board;

[0028] Rotation: Reverse-start the second driving member, and through the ratchet transmission and the synchronous belt assembly transmission, realize the rotation of the milling head located at the milling position, and at this time the other milling head does not rotate;

[0029] Second milling: Reverse-start the feed mechanism to drive the milling cutter head to feed and perform the second milling on the surface of the circuit board to be processed.

[0030] In summary, the present application includes at least one of the following beneficial technical effects:

[0031] 1. In the present application, two milling cutter heads are provided to perform forward and reverse milling on the surface of the circuit board to be processed, thereby reducing the length of the curled edge and meeting the processing requirements of the circuit board;

[0032] 2. In a further setting of the present application, a regulating mechanism is provided, which is not only used to adjust the milling allowance of the milling cutter head, but also can be used to switch between the two milling cutter heads;

[0033] 3. In a further setting of the present application, a milling mechanism is provided to prevent the two milling cutter heads from rotating simultaneously and to enable the two milling cutter heads to rotate in opposite directions, avoiding the confusion of milling lines on the surface to be processed after forward and reverse milling. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a top view schematic diagram of the circuit board and the milling cutter head during forward milling;

[0035] Figure 2 is a top view schematic diagram of the circuit board and the milling cutter head during reverse milling;

[0036] Figure 3 is Figure 4 an enlarged schematic diagram of the comparison before and after processing at position A in

[0037] Figure 4 is Figure 4 an enlarged schematic diagram of the comparison before and after processing at position B in

[0038] Figure 5 is a structural schematic diagram of a circuit board edge milling device;

[0039] Figure 6 is a structural schematic diagram of the drive assembly;

[0040] Figure 7 is a partial structural schematic diagram of the transmission mechanism;

[0041] Figure 8 is a top view schematic diagram before adjusting the milling allowance;

[0042] Figure 9 is a top view schematic diagram after adjusting the milling allowance.

[0043] Description of reference numerals: 1, base; 2, material loading table; 3, fixture; 31, pressing plate; 32, positioning column; 33, telescopic mechanism; 4, circuit board; 41, board body; 42, surface to be processed; 43, groove; 44, first milling layer; 45, second milling layer; 46, curled edge; 5, drive assembly; 51, feeding mechanism; 52, adjusting mechanism; 521, first driving member; 522, first mounting seat; 523, rotating box; 53, milling mechanism; 531, second driving member; 532, second mounting seat; 533, gearbox; 6, angle detection mechanism; 61, angle detector; 62, torsion spring; 7, transmission mechanism; 71, output shaft; 72, ratchet wheel; 73, ratchet gear; 74, synchronous belt assembly; 8, milling cutter head; 9, tool holder; 100, radius; 101, center distance; 102, measured angle. Detailed implementation manners

[0044] The following further describes the present application in detail with reference to the Figures 1-9 accompanying drawings.

[0045] An embodiment of the present application discloses a circuit board edge milling device, which mills the edge of the circuit board 4 provided with a groove 43. By providing two milling cutter heads 8 with opposite blade orientations, opposite rotations, and opposite feeding directions, the front and back milling of the surface to be processed 42 of the circuit board 4 is respectively performed, so as to reduce the length of the curled edge 46 at the notch of the groove 43. Multiple front and back milling operations can be performed according to the processing requirements until the length of the curled edge 46 reaches the processing requirements.

[0046] Taking one front and back milling operation as an example in the embodiment of the present application:

[0047] As shown in the Figures 1-2 accompanying drawings, a groove 43 is provided on the surface to be processed 42 of the circuit board 4. At this time, the left milling cutter head 8 mills the surface to be processed 42 in a clockwise rotation and backward feeding manner, and the milling allowance at this time is the thickness of the first milling layer 44. As shown in the Figures 3-4 accompanying drawings, after processing, a curled edge 46 curling into the groove 43 will appear at the front notch of the groove 43, and no curled edge 46 will appear at the rear notch of the groove 43.

[0048] After the milling of the first milling layer 44 is completed, the positions of the two milling cutter heads 8 are switched and the milling allowance is adjusted. At this time, the left milling cutter head 8 mills the surface to be processed 42 in a counterclockwise rotation and forward feeding manner, and the milling allowance at this time is the thickness of the second milling layer 45. The thickness of the second milling layer 45 is less than the thickness of the first milling layer 44. At this time, the curled edge 46 at the front notch of the groove 43 is milled off, and a new curled edge 46 will be formed at the rear notch of the groove 43, but the length of the new curled edge 46 is less than the curled edge 46 at the front notch. At this time, the length of the rear curled edge 46 is within the allowable range of processing.

[0049] If the length of the rear hem 46 exceeds the allowable range of processing, repeat the above positive and negative milling steps and successively reduce the milling layer thickness until the length of the hem 46 meets the processing requirements.

[0050] Specifically, as shown in the attached Figure 5 figure, the device includes a base 1, a loading table 2, a fixture 3, two milling heads 8, and a driving assembly 5 that provides power. The driving assembly 5 includes a milling mechanism 53, a feeding mechanism 51, and an adjusting mechanism 52.

[0051] Among them, the loading table 2 is arranged on the left side of the upper end of the base 1, the driving assembly 5 is arranged on the right side of the loading table 2, the two milling heads 8 are installed above the driving assembly 5, and the two milling heads 8 are arranged in the left-right direction. The fixture 3 is arranged on the loading table 2 and includes a positioning column 32, a pressing plate 31, and a telescopic mechanism 33. The positioning column 32 is slidably arranged along the left-right direction on the upper end of the loading table 2, and the pressing plate 31 is installed on the upper end of the positioning column 32 and can press the circuit board 4 against the upper end surface of the loading table 2. The left end surface of the circuit board 4 abuts against the positioning column 32, and the right end surface of the circuit board 4 is the surface 42 to be processed.

[0052] The telescopic mechanism 33 is connected to the left end of the positioning column 32. In this embodiment, the telescopic mechanism 33 is a cylinder. By driving the cylinder, the positioning column 32 slides to the right, thereby pushing the circuit board 4 to slide to the right until the surface 42 to be processed of the circuit board 4 is flush with the center line of the milling head 8 on the left side. The circuit board 4 is pushed by the cylinder to slide continuously and smoothly.

[0053] For the driving assembly 5, as shown in the attached Figures 6-7 figure, the feeding mechanism 51, the adjusting mechanism 52, and the milling mechanism 53 are arranged in sequence from bottom to top.

[0054] Among them, the feeding mechanism 51 is fixedly installed on the base 1. In this embodiment, the feeding mechanism 51 is an electric guide rail. The feeding direction of the electric guide rail is along the front-rear direction and is parallel to the length direction of the positioning column 32. The left end surface of the circuit board 4 abuts against the right end surface of the positioning column 32, that is, the left and right end surfaces of the circuit board 4 both extend along the front-rear direction. Thus, when the electric guide rail drives the milling head 8 to feed in the front-rear direction and mills the surface 42 to be processed of the circuit board 4, the flatness of the surface 42 to be processed after milling can be ensured.

[0055] The adjusting mechanism 52 includes a first mounting seat 522, a driving member 521, and a rotating box 523. In this embodiment, the driving member 521 is a rotating motor. The rotating box 523 is strip-shaped when viewed from above. The output end of the motor is connected to the center of the lower end of the rotating box 523. The two milling heads 8 are eccentrically arranged on the upper end surface of the rotating box 523 and are symmetric about the center of the rotating box 523 in the left-right direction. The milling head 8 on the left side is in the processing position, and the milling head 8 on the right side is in the switching position.

[0056] The first mounting seat 522 is a motor mounting seat for mounting the motor, and the first mounting seat 522 is connected to the feeding mechanism 51. The first mounting seat 522 is driven by the feeding mechanism 51 to slide, so as to realize the forward and backward feeding of the milling cutter head 8.

[0057] The rotation of the rotating box 523 is driven by the motor, so as to drive the milling cutter head 8 to rotate around the output end of the motor. Based on the rotation angle of the rotating box 523, the milling allowance of the milling cutter head 8 on the processing position for the circuit board 4 can be adjusted, and the milling cutter head 8 located at the switching position can also be rotated to the processing position for milling, which is convenient for the replacement of the milling cutter head 8.

[0058] The rotation angle range of the motor driving the rotating box 523 is between 0° and 180°, which can meet the adjustment of the milling allowance and the replacement of the milling cutter head 8.

[0059] In addition, in order to facilitate the calculation of the milling allowance, an angle detection mechanism 6 is arranged on the first mounting seat 522 for detecting the rotation angle of the motor output shaft, that is, the rotation angle of the rotating box 523. Since the detection range is between 0° and 180°, in this embodiment, the angle detection mechanism 6 can adopt an existing angle detector 61, and the milling allowance is calculated by detecting the rotation angle of the rotating box 523.

[0060] As shown in the appendix Figures 8-9 As shown, initially, the surface 42 to be processed of the circuit board 4 is aligned with the center line of the left milling cutter head 8 by pushing with the air cylinder, and before processing, the radius 100 of the milling cutter head 8 and the distance between the center of the milling cutter head 8 and the center of the rotating box 523, that is, the center distance 101, can be directly measured. After the adjusting mechanism 52 drives the rotating box 523 to rotate, the measured angle 102 is detected by the angle detector 61, and the milling allowance is calculated through the formula d = r - l * (1 - |cosα|), where d is the milling allowance; r is the radius 100; l is the center distance 101; α is the measured angle 102; |cosα| is the absolute value of the cosine value of the measured angle 102. The calculated value of d should be greater than or equal to 0.

[0061] The milling mechanism 53 includes a second mounting seat 532, a second driving member 531, a gearbox 533, two sets of ratchet transmissions and two sets of synchronous belt assemblies 74. In this embodiment, the second driving member 531 is a motor, the second mounting seat 532 is a motor mounting seat, and the motor mounting seat, the motor and the gearbox 533 are fixedly arranged in sequence from bottom to top between the motor output shaft 71 and the rotating box 523.

[0062] The ratchet drive and synchronous belt assembly 74 is disposed within the rotating box 523. The output end of the motor is connected to the gearbox 533. The output shaft 71 of the gearbox 533 extends into the rotating box 523 and is connected to two sets of ratchet drives. The ratchet drive includes a pawl wheel 72 and a ratchet gear 73. The pawl wheels 72 of the two sets of ratchet drives are both connected to the output shaft 71. The ratchet gears 73 of the two sets of ratchet drives are respectively meshed with the two pawl wheels 72, and the meshing directions of the two sets of ratchet drives are opposite. The two sets of synchronous belt assemblies 74 are respectively connected between the two ratchet gears 73 and the two milling heads 8.

[0063] By driving the motor, the two pawl wheels 72 rotate. Since the meshing directions of the two sets of ratchet drives are opposite, power transmission is only carried out through one side of the ratchet drive and the synchronous belt assembly 74, so that the milling head 8 on the corresponding side rotates. By controlling the driving direction of the motor, only the milling head 8 on the left side in the machining position rotates for milling; after switching the positions of the two milling heads 8 through the adjusting mechanism 52, at this time the other milling head 8 is in the machining position, and by driving the motor in the reverse direction, the other milling head 8 can be rotated, and the rotation directions of the two milling heads 8 are opposite, so that the two milling heads 8 can be respectively used for milling during forward and reverse feeding, avoiding the milling lines on the surface 42 to be machined from being chaotic.

[0064] For the convenience of installation, the milling head 8 is installed on the tool holder 9, and the tool holder 9 is connected to the output end of the synchronous belt assembly 74.

[0065] The embodiment of the present application also discloses a process method applying the circuit board edge milling equipment. The process steps include:

[0066] Loading: The circuit board 4 is placed on the loading table 2, the end surface on the opposite side of the surface 42 to be machined abuts against the positioning post 32, and the circuit board 4 is pressed by the pressing plate 31;

[0067] First adjustment: Start the driving member 521 and drive the rotating box 523 to rotate, and adjust the machining allowance of one of the milling heads 8 for the circuit board 4;

[0068] Rotation: Start the driving member 531, and through the ratchet drive and the synchronous belt assembly 74 for transmission, the milling head 8 for milling rotates, and at this time the other milling head 8 does not rotate;

[0069] First milling: Start the feeding mechanism 51, so as to drive the adjusting mechanism 52, the milling mechanism 53 and the milling head 8 to feed synchronously, and mill the surface 42 to be machined of the circuit board 4;

[0070] Second adjustment: After the first milling is completed, start the driving member 521, drive the rotating box 523 to rotate and make the other milling head 8 rotate to the milling position, and adjust the machining allowance of this milling head 8 for the circuit board 4;

[0071] Rotation: Reverse-start the driving part two 531. Through ratchet drive and synchronous belt assembly 74 drive, the milling cutter head 8 located at the milling position rotates, and at this time the other milling cutter head 8 does not rotate.

[0072] Second milling: Reverse-start the feeding mechanism 51, thereby driving the milling cutter head 8 to feed and perform a second milling on the surface to be processed 42 of the circuit board 4.

[0073] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A circuit board edge milling device, comprising a base (1) and a material loading table (2), characterized in that: It further includes: A fixture (3): installed on the loading table (2) and used to clamp the circuit board (4) to be processed; A milling cutter head (8): used to mill the edge of the circuit board (4); A driving assembly (5): includes a milling mechanism (53) for driving the milling cutter head (8) to rotate, a feeding mechanism (51) for driving the milling cutter head (8) to translate in both forward and reverse directions along the surface to be processed (42) of the circuit board (4), and an adjusting mechanism (52) for adjusting the milling allowance of the milling cutter head (8); The adjusting mechanism (52) includes a rotating box (523) for installing the milling cutter head (8), and a first driving member (521) installed on the feeding mechanism (51) and driving the rotating box (523) to rotate; Two milling cutter heads (8) are provided and are symmetrically arranged with the output end of the first driving member (521) as the center; The milling mechanism (53) is arranged on the rotating box (523), and it includes a second driving member (531) and a transmission mechanism (7). The transmission mechanism (7) includes two sets of ratchet transmissions with opposite meshing directions. The ratchet transmission includes a pawl wheel (72) and a ratchet gear (73). Both pawl wheels (72) are connected to the output end of the second driving member (531). The two milling cutter heads (8) are respectively connected to the two ratchet gears (73) through rotating shafts, and the blades of the two milling cutter heads (8) face in opposite directions.

2. The edge milling device for a circuit board according to claim 1, wherein: The fixture (3) includes a positioning post (32) slidably installed on the loading table (2), and a pressing plate (31) for pressing the circuit board (4). The end face on the side opposite to the surface to be processed (42) abuts against the positioning post (32). The positioning post (32) is parallel to the feeding mechanism (51), and the feeding mechanism (51) is arranged on the base (1).

3. The edge milling device for a circuit board according to claim 1, characterized in that: The output end of the first driving member (521) is fixedly connected to the rotating box (523), and the milling cutter head (8) is eccentrically arranged with respect to the output end of the first driving member (521).

4. A circuit board edge milling device according to claim 3, characterized in that: An angle detection mechanism (6) is arranged between the first driving member (521) and the rotating box (523).

5. The edge milling device for a circuit board according to claim 3, wherein: The rotation angle range of the rotating box (523) is: 0° to 180°.

6. The edge milling device for a circuit board according to claim 1, wherein: A synchronous belt assembly (74) is connected between the ratchet gear (73) and the milling cutter head (8).

7. A process method of applying the circuit board edge milling equipment as described in claim 6, characterized in that: It includes the following steps: Loading: Place the circuit board (4) on the loading table (2), abut the end face on the side opposite to the surface to be processed (42) against the positioning post (32), and press the circuit board (4) through the pressing plate (31); First adjustment: Start the first driving member (521) and drive the rotating box (523) to rotate, and adjust the machining allowance of one of the milling cutter heads (8) for the circuit board (4); Rotation: Start the second driving member (531), and through the ratchet transmission and the synchronous belt assembly (74) transmission, realize the rotation of the milling cutter head (8) for milling. At this time, the other milling cutter head (8) does not rotate; First milling: Start the feeding mechanism (51), thereby driving the adjusting mechanism (52), the milling mechanism (53) and the milling cutter head (8) to feed synchronously, and mill the surface to be processed (42) of the circuit board (4); Second adjustment: After the first milling is completed, start the first driving member (521), drive the rotating box (523) to rotate and make another milling cutter head (8) rotate to the milling position, and adjust the machining allowance of the milling cutter head (8) for the circuit board (4); Rotation: Reverse-start the second driving member (531), and through ratchet drive and synchronous belt assembly (74) drive, realize the rotation of the milling cutter head (8) located at the milling position, and at this time the other milling cutter head (8) does not rotate; Second milling: Reverse-start the feeding mechanism (51), so as to drive the milling cutter head (8) to feed and perform a second milling on the surface to be machined (42) of the circuit board (4).

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