Leveling device of printed circuit board

Abstract

The invention discloses a leveling device of a printed circuit board, and relates to the technical field of circuit board leveling, the leveling device comprises a leveling machine table, the front surface of the leveling machine table is provided with a conveying device, the inner side of the leveling machine table is provided with a processing table, the inside of the leveling machine table is provided with a hydraulic cylinder, the bottom end of the hydraulic cylinder is connected with a leveling plate, and the leveling plate is provided with a positioning device. The device further comprises a pressure control mechanism, the pressure control mechanism comprises two sets of cavities, the cavities are formed in the leveling machine table, fixed tables are fixed to the inner walls of the cavities, movable rods are arranged in the cavities in a sleeved mode, one ends of the movable rods penetrate through the cavities and are connected with extrusion plates, U-shaped plates are fixed to the other ends of the movable rods, and the U-shaped plates are connected with the fixed tables. The board warping degrees of the two sides of the printed circuit board are sensed through the pressure control mechanism, the flow entering the hydraulic cylinder is adjusted through the flow control valve, and then the movement speed and the output force of the hydraulic cylinder can be adjusted, so that the device adapts to the printed circuit boards with different board warping degrees.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board leveling, and specifically to a leveling device for printed circuit boards. Background Art

[0002] A printed circuit board, also known as a printed wiring board, printed circuit board, abbreviated as PCB or PWB in English, is an important electronic component, a support for electronic components, and a provider of electrical connections for electronic components. Since it is made by electronic printing technology, it is called a "printed" circuit board.

[0003] During the manufacturing process of circuit boards, the board material is affected by factors such as thermal expansion and contraction, and is prone to warping problems. Especially in the manufacturing process of multi-layer circuit boards, due to the uneven thermal expansion and contraction of the internal copper foil, it is very easy to cause the board surface to warp, thus affecting the quality and performance of the circuit board. The circuit board leveling machine is an essential part of the circuit board manufacturing process. Most of the existing circuit board leveling machines use mechanical leveling methods, applying pressure to the printed circuit board to make it flat. For example, the molding leveling machine proposed in the publication number "CN207558764U". When applying pressure to the circuit board, it is necessary to preset the pressure value for the circuit board. Since the degree of warping of different circuit boards varies, when applying pressure to a circuit board with a higher degree of warping, a higher pressure is required to make the circuit board flat. If the same pressure is applied to a circuit board with a lower degree of warping deformation, it is easy to cause damage to the circuit board. Therefore, when leveling the circuit board, it is necessary to observe the degree of warping of the circuit board and frequently adjust the pressure value of the circuit board leveling machine, which affects the efficiency of leveling the circuit board. Summary of the Invention

[0004] The purpose of the present invention is to make up for the deficiencies of the prior art and provide a leveling device for printed circuit boards.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A leveling device for printed circuit boards, including a leveling machine table. A conveying device is arranged on the front surface of the leveling machine table. A processing table is arranged inside the leveling machine table. A hydraulic cylinder is assembled inside the leveling machine table. The bottom end of the hydraulic cylinder is connected to a leveling plate. It further includes:

[0006] A pressure control mechanism, which is arranged on the leveling machine table and is used to control the extrusion force on the printed circuit board;

[0007] Among them, the pressure control mechanism includes two groups of cavities. The cavities are arranged inside the leveling machine table. A fixed table is fixed on the inner wall of the cavity. A movable rod is sleeved inside the cavity. One end of the movable rod passes through the cavity and is connected with a pressing plate. The other end of the movable rod is fixed with a U-shaped plate. The top of the pressing plate is slidably connected with a movable frame. One side of the movable frame is connected with a baffle through a connecting frame. The other side of the movable frame is fixed with a connecting shaft. A movable part is sleeved on the outer surface of the connecting shaft. A notch is opened above the cavity. The top of the movable part is connected with a sleeve. An extrusion shaft and a compression spring are slidably connected inside the sleeve. A double-shaft motor is installed inside the processing table. Output shafts at both ends of the double-shaft motor are both connected with threaded rods. Two groups of pressure sensors are installed inside the leveling machine table.

[0008] As a preferred solution of the present invention, a sliding table cylinder is fixed on one side of the top of the leveling plate. The sliding table cylinder is fixed with a push plate in cooperation with its slider.

[0009] As a preferred solution of the present invention, a chamfer is provided at the end of the connecting shaft. The fixed table is trapezoidal. The chamfered part of the cavity is in pressing contact with the inclined surface of the fixed table.

[0010] As a preferred solution of the present invention, the bottom surface of the baffle is in pressing contact with the edge of the top surface of the printed circuit board. The bottom surface of the pressing plate is flush with the top surface of the processing table. The pressing plate is in pressing contact with both sides of the printed circuit board, and rubber is bonded to the pressing surface of the pressing plate and the printed circuit board.

[0011] As a preferred solution of the present invention, the thread directions of the outer surfaces of the two threaded rods are opposite, and the threaded rods are in threaded connection with the U-shaped plate.

[0012] As a preferred solution of the present invention, the top end of the extrusion shaft is in pressing contact with the pressure sensor. The sleeve is slidably connected with the notch.

[0013] As a preferred solution of the present invention, the compression spring elastically supports between the extrusion shaft and the movable part.

[0014] As a preferred solution of the present invention, the push plate is strip-shaped, and the thickness of the push plate is less than the thickness of the printed circuit board. The push plate is in pressing contact with one side of the printed circuit board.

[0015] As a preferred solution of the present invention, the pressure sensor records data through a single-chip microcomputer, and the single-chip microcomputer adjusts the pressure of the hydraulic cylinder by controlling a flow control valve.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The present invention respectively senses the warpage degrees on both sides of the printed circuit board through a pressure control mechanism, records the pressure changes of two groups of pressure sensors by a single-chip microcomputer, records the minimum pressure detected by each group of pressure sensors, compares the numerical values of the minimum pressures detected by the two groups of pressure sensors, and takes the larger pressure value. This value corresponds to the maximum warpage degree on both sides of the printed circuit board. At this time, the single-chip microcomputer controls a flow control valve, and the flow control valve is used to adjust the flow rate into the hydraulic cylinder, thereby adjusting the movement speed and output force of the hydraulic cylinder to adapt to printed circuit boards with different warpage degrees and avoiding excessive pressure on the printed circuit board.

[0018] 2. The present invention realizes the cooperation between the threaded rod and the U-shaped plate. Since the thread directions on the outer surfaces of the two threaded rods are opposite, when the threaded rods rotate, the two U-shaped plates will move towards or away from each other, which is convenient for centering the printed circuit board and sensing the warpage degree of the printed circuit board. After centering the printed circuit board and detecting its warpage degree, the pressing plate is controlled to separate from the printed circuit board, facilitating continuous processing.

[0019] 3. The present invention controls the push plate to slide along the bottom surface of the flattening plate through a sliding table cylinder. Since the push plate is strip-shaped and its thickness is less than the thickness of the printed circuit board, when the flattening plate flattens the printed circuit board, the push plate does not contact the upper surface of the printed circuit board. Thus, the push plate can be used to push the printed circuit board to move, facilitating continuous flattening of the printed circuit board.

[0020] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be learned from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a three-dimensional structural schematic diagram of the present invention;

[0022] Figure 2 is a partial cross-sectional structural schematic diagram of the front of the present invention;

[0023] Figure 3 is the present invention Figure 2 the enlarged structural schematic diagram at A in;

[0024] Figure 4 is the disassembly structural schematic diagram of the hydraulic cylinder of the present invention;

[0025] Figure 5 is the disassembly structural schematic diagram of the processing table and the flattening plate of the present invention;

[0026] Figure 6 is the disassembly structural schematic diagram of the double-shaft motor and the U-shaped plate of the present invention;

[0027] Figure 7 This is a schematic diagram of the partial sectional structure of the leveling machine table of the present invention;

[0028] Figure 8 For the present invention Figure 7 Schematic diagram of the enlarged partial structure;

[0029] Figure 9 This is a schematic diagram of the principle structure of the hydraulic cylinder pressure regulation of the present invention.

[0030] In the figure: 1. Leveling machine table; 2. Conveying device; 3. Processing table; 4. Hydraulic cylinder; 5. Leveling plate; 6. Cavity; 7. Fixed table; 8. Movable rod; 9. Extrusion plate; 10. U-shaped plate; 11. Movable frame; 12. Connecting frame; 13. Baffle; 14. Connecting shaft; 15. Movable part; 16. Notch; 17. Sleeve; 18. Extrusion shaft; 19. Compression spring; 20. Biaxial motor; 21. Threaded rod; 22. Slide cylinder; 23. Push plate; 24. Pressure sensor. Detailed implementation manners

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0032] As Figures 1-9 shown, the present invention provides a technical solution: a leveling device for printed circuit boards, including a leveling machine table 1, a conveying device 2 is arranged on the front of the leveling machine table 1, a processing table 3 is arranged inside the leveling machine table 1, a hydraulic cylinder 4 is assembled inside the leveling machine table 1, the bottom end of the hydraulic cylinder 4 is connected to a leveling plate 5, and further includes:

[0033] A pressure control mechanism, which is arranged on the leveling machine table 1 and is used to control the force of extruding the printed circuit board;

[0034] Among them, the pressure control mechanism includes two groups of cavities 6. The cavities 6 are arranged inside the leveling machine table 1. A fixed table 7 is fixed on the inner wall of the cavity 6. A movable rod 8 is sleeved inside the cavity 6. One end of the movable rod 8 passes through the cavity 6 and is connected with a pressing plate 9. The other end of the movable rod 8 is fixed with a U-shaped plate 10. The top of the pressing plate 9 is slidably connected with a movable frame 11. One side of the movable frame 11 is connected with a baffle 13 through a connecting frame 12. The other side of the movable frame 11 is fixed with a connecting shaft 14. An activity member 15 is sleeved on the outer surface of the connecting shaft 14. A notch 16 is opened above the cavity 6. The top of the activity member 15 is connected with a sleeve 17. An extrusion shaft 18 and a compression spring 19 are slidably connected inside the sleeve 17. A double-shaft motor 20 is installed inside the processing table 3. The output shafts at both ends of the double-shaft motor 20 are both connected with threaded rods 21. Two groups of pressure sensors 24 are installed inside the leveling machine table 1.

[0035] By running the double-shaft motor 20, the rotation of the two groups of threaded rods 21 can be controlled. At the same time, through the cooperation between the threaded rods 21 and the U-shaped plate 10, the movable rod 8 will be driven by the U-shaped plate 10 to slide along the inner side of the cavity 6, so that the printed circuit board can be pushed by the two groups of pressing plates 9, making the pressing plate 9 centered on the top of the processing table 3. At the same time, when the pressing plate 9 presses against the printed circuit board, the connecting shaft 14 will also separate from the top of the fixed table 7. At this time, the elastic force of the compression spring 19 will drive the activity member 15 and the connecting shaft 14 to move the baffle 13 downward. Therefore, the edge of the top surface of the printed circuit board can be pressed by the baffle 13. At this time, the pressure sensed by the pressure sensor 24 will change, and the pressure sensed by the pressure sensor 24 will also be different with the degree of board warping of the printed circuit board. Therefore, the smaller the pressure sensed by the pressure sensor 24, the smaller the degree of board warping. Furthermore, the single-chip microcomputer can be used to adjust the extrusion force of the hydraulic cylinder 4 accordingly. After adjusting the extrusion force of the hydraulic cylinder 4, it is necessary to control the separation of the pressing plate 9 from the printed circuit board to facilitate subsequent leveling operations.

[0036] As Figure 4 、 5 shown, a slide table cylinder 22 is fixed on one side of the top of the leveling plate 5. The slide table cylinder 22 is fixed with a push plate 23 in cooperation with its slider.

[0037] Through the cooperation between the slide table cylinder 22 and the push plate 23, the push plate 23 can be controlled by the slide table cylinder 22 to move along the bottom of the leveling plate 5. Thus, after the leveling plate 5 levels the printed circuit board, the hydraulic cylinder 4 is slightly lifted. At this time, the printed circuit board can be pushed out by the push plate 23, facilitating continuous processing.

[0038] As Figure 8 shown, a chamfer is provided at the end of the connecting shaft 14. The fixed table 7 is trapezoidal. The chamfered part of the cavity 6 is in pressing contact with the inclined surface of the fixed table 7.

[0039] Through the design of the connecting shaft 14, since chamfers are provided at the ends of the connecting shaft 14, when controlling the reset of the connecting shaft 14, the chamfered portion of the connecting shaft 14 will cause extrusion with the inclined surface of the fixed table 7, and then the connecting shaft 14 will drive the movable frame 11 to move upward along the inner side of the pressing plate 9, facilitating the induction of the warpage length of the next group of printed circuit boards.

[0040] As Figure 5 、 6 shown, the bottom surface of the baffle 13 is in extrusion contact with the edge of the top surface of the printed circuit board, the bottom surface of the pressing plate 9 is flush with the top surface of the processing table 3, the pressing plate 9 is in extrusion contact with both sides of the printed circuit board, and rubber is bonded to the extrusion surface of the printed circuit board.

[0041] Through the cooperation between the baffle 13 and the printed circuit board, when the baffle 13 extrudes the printed circuit board, as the warpage degree of the printed circuit board is different, the amplitude of the downward movement of the baffle 13 is also different. The greater the amplitude of the downward movement of the baffle 13, the lower the warpage degree of the printed circuit board. At this time, the force exerted by the compression spring 19 on the extrusion shaft 18 will also be lower, and then the pressure sensed by the pressure sensor 24 will change.

[0042] As Figure 6 shown, the thread directions on the outer surfaces of the two groups of threaded rods 21 are opposite, and the threaded rods 21 are threadedly connected to the U-shaped plate 10.

[0043] Through the cooperation between the threaded rods 21 and the U-shaped plate 10, and since the thread directions on the outer surfaces of the two groups of threaded rods 21 are opposite, when the threaded rods 21 rotate, they will drive the two groups of U-shaped plates 10 to move towards or away from each other, facilitating the centering of the printed circuit board and facilitating the flattening of the printed circuit board by the flattening plate 5.

[0044] As Figure 3 shown, the top end of the extrusion shaft 18 is in extrusion contact with the pressure sensor 24, and the sleeve 17 is slidably connected to the notch 16.

[0045] Through the cooperation between the extrusion shaft 18 and the pressure sensor 24, when the extrusion shaft 18 extrudes the pressure sensor 24, the extrusion force will be sensed by the pressure sensor 24. Therefore, the pressure exerted by the extrusion shaft 18 on the pressure sensor 24 can be controlled by the movement of the connecting shaft 14 and the movable part 15.

[0046] As Figure 3 shown, the compression spring 19 is elastically supported between the extrusion shaft 18 and the movable part 15.

[0047] Through the design of the compression spring 19, the extrusion shaft 18 has good elastic reset performance. At this time, since the compression spring 19 is in a compressed state, it will exert an elastic force on the extrusion shaft 18, so that a pressure can be applied to the pressure sensor 24 through the extrusion shaft 18, and then the warpage degree of the printed circuit board can be determined by the pressure sensed by the pressure sensor 24.

[0048] As Figure 4 shown, the push plate 23 is strip-shaped, and the thickness of the push plate 23 is less than the thickness of the printed circuit board. The push plate 23 is in extrusion contact with one side of the printed circuit board.

[0049] Through the design of the push plate 23, since the push plate 23 is strip-shaped and its thickness is less than the thickness of the printed circuit board, when the flattening plate 5 flattens the printed circuit board, the push plate 23 does not contact the upper surface of the printed circuit board, and then the push plate 23 can be used to push the printed circuit board to move.

[0050] As Figure 9 shown, the pressure sensor 24 records data through a single-chip microcomputer, and the single-chip microcomputer adjusts the pressure of the hydraulic cylinder 4 by controlling the flow control valve.

[0051] By using two groups of pressure sensors 24 to sense the warpage degrees on both sides of the printed circuit board respectively, it is necessary to use a single-chip microcomputer to record the pressure changes of the two groups of pressure sensors 24, record the minimum pressure detected by each group of pressure sensors 24, and compare the numerical values of the minimum pressures detected by the two groups of pressure sensors 24, and take the larger pressure value. This value is the warpage degree of the printed circuit board. Then, use the single-chip microcomputer to control the flow control valve, and use the flow control valve to adjust the flow rate entering the hydraulic cylinder 4, so as to adjust the movement speed and output force of the hydraulic cylinder 4 to adapt to printed circuit boards with different warpage degrees.

[0052] Working principle:

[0053] First, by operating the biaxial motor 20, the rotation of two groups of threaded rods 21 can be controlled. At the same time, through the cooperation between the threaded rods 21 and the U-shaped plate 10, the movable rod 8 will be driven by the U-shaped plate 10 to slide along the inner side of the cavity 6, so that the printed circuit board can be pushed by two groups of pressing plates 9. At the same time, when the pressing plate 9 presses against the printed circuit board, the connecting shaft 14 will separate from the top of the fixed table 7. At this time, the elastic force of the compression spring 19 will drive the movable part 15 and the connecting shaft 14 to move the baffle 13 downward. Therefore, the edge of the top surface of the printed circuit board can be pressed by the baffle 13. At this time, the pressure sensed by the pressure sensor 24 will change, and the pressure sensed by the pressure sensor 24 will also be different with the degree of warping of the printed circuit board. The degree of warping of both sides of the printed circuit board is sensed by two groups of pressure sensors 24 respectively. At this time, it is necessary to use the single-chip microcomputer to record the pressure changes of the two groups of pressure sensors 24, record the minimum pressure detected by each group of pressure sensors 24, and compare the numerical values of the minimum pressures detected by the two groups of pressure sensors 24, and take the larger pressure value. This value is the degree of warping of the printed circuit board. Then, use the single-chip microcomputer to control the flow control valve, and use the flow control valve to adjust the flow rate into the hydraulic cylinder 4, so as to adjust the movement speed and output force of the hydraulic cylinder 4. Adjust the pressure output shaft of the hydraulic cylinder 4 to control the separation of the pressing plate 9 from the printed circuit board. Then start the hydraulic cylinder 4 to control the flattening plate 5 to flatten the printed circuit board. After flattening, make the flattening plate 5 slightly separate from the printed circuit board. At this time, by operating the slide cylinder 22, the printed circuit board can be pushed out by the push plate 23.

[0054] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A printed circuit board leveling device, comprising a leveling machine platform, a conveying device is arranged on the front of the leveling machine platform, a processing table is arranged on the inner side of the leveling machine platform, a hydraulic cylinder is installed inside the leveling machine platform, and a leveling plate is connected to the bottom end of the hydraulic cylinder, characterized in that: Also includes: A pressure control mechanism, which is arranged on the flattening machine platform and is used to control the force of squeezing the printed circuit board; Among them, the pressure control mechanism includes two groups of cavities, the cavity is arranged inside the leveling machine platform, the inner wall of the cavity is fixed with a fixed platform, the interior of the cavity is sleeved with a movable rod, one end of the movable rod passes through the cavity and is connected to an extrusion plate, the other end of the movable rod is fixed with a U-shaped plate, the top of the extrusion plate is slidably connected to a movable frame, one side of the movable frame is connected to a baffle through a connecting frame, a connecting shaft is fixed to the other side of the movable frame, the outer surface of the connecting shaft is sleeved with a movable part, a notch is opened above the cavity, the top of the movable part is connected with a sleeve, the interior of the sleeve is slidably connected with an extrusion shaft and a compression spring, a dual-axis motor is installed inside the processing table, the output shafts at both ends of the dual-axis motor are connected to threaded rods, and two groups of pressure sensors are installed inside the leveling machine platform.

2. A printed circuit board flattening device according to claim 1, characterized in that: A slide cylinder is fixed on one side of the top of the screed plate, and a push plate is fixed to the slide cylinder in cooperation with its slider.

3. A printed circuit board flattening device according to claim 1, characterized in that: The end of the connecting shaft is provided with a chamfer, the fixing platform is trapezoidal, and the chamfer of the cavity is in extrusion contact with the inclined surface of the fixing platform.

4. A printed circuit board flattening device according to claim 1, characterized in that: The bottom surface of the baffle is in extrusion contact with the edge of the top surface of the printed circuit board, the bottom surface of the extrusion plate is flush with the top surface of the processing table, the extrusion plate is in extrusion contact with both sides of the printed circuit board, and rubber is bonded to the extrusion surface of the printed circuit board.

5. A printed circuit board flattening device according to claim 1, characterized in that: The threads on the outer surfaces of the two groups of threaded rods are in opposite directions, and the threaded rods are threadedly connected to the U-shaped plates.

6. A printed circuit board flattening device according to claim 1, characterized in that: The top end of the extrusion shaft is in extrusion contact with the pressure sensor, and the sleeve is slidably connected with the notch.

7. A printed circuit board flattening device according to claim 1, characterized in that: The compression spring is elastically supported between the extrusion shaft and the movable member.

8. A printed circuit board flattening device according to claim 2, characterized in that: The push plate is in a long strip shape, and the thickness of the push plate is less than the thickness of the printed circuit board. The push plate is in extrusion contact with one side of the printed circuit board.

9. A printed circuit board flattening device according to claim 1, characterized in that: The pressure sensor records data via a single chip microcomputer, and the single chip microcomputer adjusts the pressure of the hydraulic cylinder by controlling a flow control valve.

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