A PCB circuit board vacuum fast pressing machine

Abstract

The present invention relates to the technical field of PCB board processing, and in particular to a PCB circuit board vacuum quick press, comprising an upper plate and a lower plate arranged up and down, a sealing cover movably arranged below the upper plate, a retaining ring 1, a retaining ring 2, and a retaining ring 3 concentrically fixed at the lower edge of the sealing cover, a buffer cavity 1 and a buffer cavity 2 are formed between the retaining ring 1, the retaining ring 2, and the retaining ring 3, and a vacuum cavity is formed between the retaining ring 3 and the sealing cover. The present invention uses a stepped exhaust mechanism to exhaust the inside of the buffer cavity 1, the buffer cavity 2, and the vacuum cavity, so that the external air pressure, the air pressure of the buffer cavity 1, the air pressure of the buffer cavity 2, and the air pressure of the buffer cavity 3 are stepped and decreased in sequence, and the small pressure difference is not enough to allow air to enter the inner side of the vacuum cavity through the gap between the sealing ring and the PCB board, thereby ensuring good sealing without applying a large pressure to the PCB board, and effectively preventing the PCB board from being indented at the edge due to excessive pressure.

Description

Technical Field

[0001] The invention relates to the technical field of PCB board processing, and in particular to a PCB circuit board vacuum fast pressing machine. Background Art

[0002] PCB is an important electronic component and the support of electronic components. In production, the inner layer circuit board, prepreg, copper foil and other materials are combined together by heat pressing to form a multi-layer PCB with a specific number of layers and thickness to meet the requirements of circuit design.

[0003] For the lamination of flexible boards, in order to prevent bubbles from forming between different layers of materials or in the glue during hot pressing, vacuum treatment is required to place the PCB board in a vacuum environment for hot pressing.

[0004] After searching, the invention patent with announcement number: CN113518518B discloses a PCB board vacuum lamination device, including a frame, a support table and a lamination mechanism, and a groove is provided on the support table; the lamination mechanism includes a first lamination unit and a second lamination unit, the first lamination unit includes a cylinder, a tension pressure sensor and a sliding plate, the sliding plate is connected to the cylinder through the tension pressure sensor, and an upper die and a sealing frame are fixed on the sliding plate, the upper die is located on the inner side of the sealing frame, and the upper die is located directly above the groove, and a vacuum pump is provided on the sealing frame; the second lamination unit includes a partition frame, a support plate and a pushing part, the partition frame is located in the groove, and the partition frame divides the groove into an inner cavity and an interlayer cavity, the support plate is slidably arranged in the inner cavity, and the support plate can push the circuit board out of the inner cavity, and the size of the inner cavity matches the size of the circuit board.

[0005] Based on the above search and combined with actual problems, it is found that: in order to ensure the sealing performance and keep the PCB board in a stable vacuum environment, the existing vacuum pressing machine for PCB boards needs to press the side of the sealing cover against the side of the PCB board, and the side of the sealing cover and the PCB board are sealed by a sealing ring. In order to improve the sealing performance, the pressure between the sealing cover and the PCB board is usually increased. However, as the pressure of the sealing cover on the PCB board increases, it is easy to cause indentations on the side of the PCB board, thereby reducing the production quality of the PCB board. Moreover, in a vacuum environment, the air pressure on the upper side of the PCB board gradually decreases, and the air on the lower side will exert upward pressure on the PCB board from the center of the lower side of the PCB board, which is easy to cause the center of the PCB board to bulge and deform, further reducing the processing quality of the PCB board. Summary of the invention

[0006] The purpose of the present invention is to provide a PCB circuit board vacuum fast pressing machine to solve the problems raised in the above background technology.

[0007] The technical solution of the present invention is: a PCB circuit board vacuum fast pressing machine, comprising an upper plate and a lower plate arranged up and down, a sealing cover movably arranged below the upper plate, a retaining ring 1, a retaining ring 2 and a retaining ring 3 are concentrically fixed at the lower edge of the sealing cover, a buffer chamber 1 and a buffer chamber 2 are formed between the retaining ring 1, the retaining ring 2 and the retaining ring 3, and a vacuum chamber is formed between the retaining ring 3 and the sealing cover; two pressure difference sensing mechanisms are arranged on the outside of the sealing cover, which respectively connect the buffer chamber 1 with the buffer chamber 2 and the buffer chamber 2 with the vacuum chamber, and the two pressure difference sensing mechanisms respectively detect the air pressure between the buffer chamber 1 and the buffer chamber 2, and the buffer chamber 2 and the vacuum chamber; a stepped exhaust mechanism is arranged on the outside of the sealing cover, and the stepped exhaust mechanism exhausts the buffer chamber 1, the buffer chamber 2 and the inner side of the vacuum chamber into different vacuum degrees.

[0008] Preferably, the pressure difference sensing mechanism includes a sensing cylinder, the inner side of which is slidably connected to a sensing piston plate, one end of which is elastically connected to an inner end of the sensing cylinder via a balance spring, and a trigger switch is installed on an inner end of the sensing cylinder away from the sensing piston plate.

[0009] Preferably, two ends of one of the sensing tubes are connected to the inner sides of buffer chamber 1 and buffer chamber 2 through two buffer chamber connecting tubes, and two ends of the other sensing tube are connected to the inner sides of buffer chamber 2 and the vacuum chamber through two buffer chamber connecting tubes.

[0010] Preferably, the stepped exhaust mechanism includes a vacuum pump installed on the outside of the sealing cover, the air inlet end of the vacuum pump is connected to a collecting pipe, three air outlet pipes are inserted on one side of the collecting pipe, one end of the three air outlet pipes is connected to a reversing pipe, one side of the reversing pipe is provided with an air intake pipe at the position corresponding to each air outlet pipe, one end of the three air intake pipes is respectively connected to the inner side of buffer chamber 1, buffer chamber 2 and vacuum chamber, and a step-by-step conduction mechanism is provided on the inner side of the reversing pipe.

[0011] Preferably, the step-by-step conduction mechanism includes a fixed valve column fixed at one end of the inner side of the reversing tube and two partitions fixed at the middle position of the inner side of the reversing tube, a fixed flow channel is opened inside the fixed valve column, and the fixed flow channel is connected with the interior of the vacuum chamber through an air suction pipe at a corresponding position, one end of the two partitions are elastically connected with movable valve columns through reset springs, the two movable valve columns are slidably connected to the inner side of the reversing tube, and movable flow channels are opened inside the two movable valve columns, the two movable flow channels are connected with the interior of buffer chamber one and buffer chamber two respectively through two air suction pipes at corresponding positions, one end of the two partitions are equipped with electromagnets, the two electromagnets are electrically connected to two trigger switches respectively, and the inner diameter ratio between the fixed flow channel and the two movable flow channels is equal to the volume ratio between the vacuum chamber, buffer chamber two and buffer chamber one.

[0012] Preferably, two downward pressure electric cylinders are installed on the upper side of the upper plate, and the telescopic ends of the two downward pressure electric cylinders are slidably connected with sliders 1, and the lower sides of the two sliders 1 are fixed with suspension rods extending to the outside, and the lower ends of the two suspension rods are fixed to the upper side of the sealing cover, and the upper sides of the two sliders 1 are elastically connected to the telescopic ends of the downward pressure electric cylinders through buffer springs.

[0013] Preferably, a plurality of pressing cylinders are installed on the lower side of the sealing cover, a pressing plate is fixed to the telescopic ends of the plurality of pressing cylinders, and a cushion is provided on the lower side of the pressing plate.

[0014] Preferably, a guide cylinder is fixed at the center position on the upper side of the pressing plate, and a pre-compression rod is slidably connected to the inner side of the guide cylinder. The upper end of the pre-compression rod is elastically connected to the inner upper end of the guide cylinder through a pre-compression spring, and the lower end of the pre-compression rod is lower than the height of a lower side of the retaining ring.

[0015] Preferably, the lower sides of the retaining ring 1, retaining ring 2 and retaining ring 3 are all wrapped with sealing rings.

[0016] Preferably, two positioning cylinders are symmetrically installed at two diagonal positions on the upper side of the lower plate, and positioning angle blocks are fixed to the telescopic ends of the two positioning cylinders.

[0017] The present invention provides a PCB circuit board vacuum fast press machine through improvement, which has the following improvements and advantages compared with the prior art:

[0018] First, the present invention forms a buffer chamber 1, a buffer chamber 2 and a vacuum chamber by means of a baffle ring 1, a baffle ring 2 and a baffle ring 3 which are concentrically arranged at the lower side of the sealing cover, and evacuates the inside of the buffer chamber 1, the buffer chamber 2 and the vacuum chamber through a stepped exhaust mechanism, so that the external air pressure, the air pressure of the buffer chamber 1, the air pressure of the buffer chamber 2 and the air pressure of the buffer chamber 3 are successively reduced in a stepped manner, so that the baffle ring 1, the baffle ring 2 and the baffle ring 3 share the pressure difference between the outside and the vacuum chamber. In this way, when the baffle ring 1, the baffle ring 2 and the baffle ring 3 do not apply too much pressure to the PCB board, the small pressure difference is not enough to make the air enter the inner side of the vacuum chamber through the gap between the sealing ring and the PCB board, so that when the baffle ring 1, the baffle ring 2 and the baffle ring 3 do not apply too much pressure to the PCB board, the small pressure difference is not enough to make the air enter the inner side of the vacuum chamber through the gap between the sealing ring and the PCB board, so that when the PCB board is not applied with a large pressure, good sealing can be guaranteed, and indentations at the edge of the PCB board caused by excessive pressure can be effectively prevented.

[0019] Secondly, the present invention uses the effect of the pre-compression rod. Since the height of the lower end of the pre-compression rod is lower than the height of the lower side of the retaining ring, when the sealing cover drives the retaining ring one, the retaining ring two, and the retaining ring three to move downward, the lower end of the pre-compression rod will contact the upper side of the PCB board before the sealing ring. Under the action of the pre-compression spring, the pre-compression rod can pre-apply a certain pressure to the center of the PCB board. In this way, when vacuuming, the center of the PCB board can be prevented from bulging and deforming upward due to the decrease in air pressure inside the vacuum chamber, thereby ensuring the flatness of the PCB board. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

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

[0023] Figure 3 It is a schematic diagram of the first cross-sectional structure of the sealing cover in the present invention;

[0024] Figure 4 It is a second cross-sectional structural schematic diagram of the sealing cover in the present invention;

[0025] Figure 5 It is a cross-sectional structural schematic diagram of the pressure difference sensing mechanism and the stepped air extraction mechanism in the present invention;

[0026] Figure 6 For the present invention Figure 5 A schematic diagram of the enlarged structure at A in the middle;

[0027] Figure 7 For the present invention Figure 5 A schematic diagram of the enlarged structure at B in the middle;

[0028] Figure 8 It is a cross-sectional structural schematic diagram of the step-by-step conduction mechanism in the present invention;

[0029] Fig. 9 For the present invention Figure 2 Schematic diagram of the enlarged structure at point C in the middle.

[0030] Reference numerals:

[0031] 1. Lower plate; 2. Upper plate; 3. Sealing cover; 4. Positioning cylinder; 5. Positioning angle block; 6. Lower pressure cylinder; 7. Slider 1; 8. Suspension rod; 9. Buffer spring; 101. Blocking ring 1; 102. Blocking ring 2; 103. Blocking ring 3; 104. Buffer chamber 1; 105. Buffer chamber 2; 106. Vacuum chamber; 107. Sealing ring; 201. Induction cylinder; 202. Induction piston plate; 203. Buffer chamber connecting pipe; 204. Balance spring; 205 , trigger switch; 301, vacuum pump; 302, collecting pipe; 303, reversing pipe; 304, exhaust pipe; 305, suction pipe; 306, fixed valve column; 307, fixed flow channel; 308, partition; 309, electromagnet; 310, return spring; 311, movable valve column; 312, movable flow channel; 401, pressing cylinder; 402, pressing plate; 403, cushion; 404, guide cylinder; 405, pre-compression rod; 406, pre-compression spring. DETAILED DESCRIPTION

[0032] The present invention is described in detail below, and the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments 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 creative work are within the scope of protection of the present invention.

[0033] The present invention provides a PCB circuit board vacuum fast pressing machine through improvement. The technical solution of the present invention is:

[0034] like Figures 1 to 9 As shown, the embodiment of the present invention provides a PCB circuit board vacuum fast pressing machine, including an upper plate 2 and a lower plate 1 arranged up and down, a sealing cover 3 is movably arranged below the upper plate 2, a retaining ring 101, a retaining ring 102, and a retaining ring 103 are concentrically fixed at the lower edge of the sealing cover 3, a buffer cavity 104 and a buffer cavity 105 are formed between the retaining ring 101, the retaining ring 102, and the retaining ring 103, and a vacuum cavity 106 is formed between the retaining ring 103 and the sealing cover 3, and the retaining ring 101, the retaining ring 102, and the retaining ring 103 are fixed to the lower edge of the sealing cover 3. The lower sides are wrapped with sealing rings 107; two pressure difference sensing mechanisms are arranged on the outside of the sealing cover 3, which respectively connect the buffer chamber 1 104 and the buffer chamber 2 105, and the buffer chamber 2 105 and the vacuum chamber 106, and the two pressure difference sensing mechanisms respectively detect the air pressure between the buffer chamber 1 104 and the buffer chamber 2 105, and the buffer chamber 2 105 and the vacuum chamber 106; a stepped exhaust mechanism is arranged on the outside of the sealing cover 3, and the stepped exhaust mechanism draws the inner sides of the buffer chamber 1 104, the buffer chamber 2 105, and the vacuum chamber 106 into different vacuum degrees.

[0035] Furthermore, the pressure difference sensing mechanism includes a sensing tube 201 (such as Figure 6As shown in the figure, the inner side of the sensing cylinder 201 is slidably connected with a sensing piston plate 202, one end of the sensing piston plate 202 is elastically connected to the inner end of the sensing cylinder 201 through a balance spring 204, and a trigger switch 205 is inserted and installed at one end of the inner side of the sensing cylinder 201 away from the sensing piston plate 202, the two ends of one sensing cylinder 201 are connected to the inner sides of the buffer chamber 1 104 and the buffer chamber 2 105 through two buffer chamber connecting tubes 203, and the two ends of the other sensing cylinder 201 are connected to the inner sides of the buffer chamber 2 105 and the vacuum chamber 106 through two buffer chamber connecting tubes 203;

[0036] The pressure difference sensing mechanism is used to sense the pressure difference between the adjacent buffer chamber 1 104 and buffer chamber 2 105 , and between the buffer chamber 2 105 and the vacuum chamber 106 .

[0037] Furthermore, the stepped exhaust mechanism includes a vacuum pump 301 installed on the outside of the sealing cover 3, the air inlet end of the vacuum pump 301 is connected to a collecting pipe 302, one side of the collecting pipe 302 is inserted with three air outlet pipes 304, one end of the three air outlet pipes 304 is connected to a reversing pipe 303, one side of the reversing pipe 303 is inserted with an air intake pipe 305 at the position corresponding to each air outlet pipe 304, one end of the three air intake pipes 305 is respectively connected to the inner side of the buffer chamber 1 104, the buffer chamber 2 105, and the vacuum chamber 106, and the inner side of the reversing pipe 303 is provided with a step-by-step conduction mechanism, which includes a fixed valve column 306 fixed at one end of the inner side of the reversing pipe 303 and two valves fixed at the inner side of the reversing pipe 303 at the middle position. A partition 308 is provided, a fixed flow channel 307 is provided inside the fixed valve column 306, and the fixed flow channel 307 is communicated with the inside of the vacuum chamber 106 through an air suction pipe 305 at a corresponding position, one end of the two partitions 308 is elastically connected to a movable valve column 311 through a reset spring 310, the two movable valve columns 311 are slidably connected to the inner side of the reversing tube 303, and the inside of the two movable valve columns 311 is provided with a movable flow channel 312, and the two movable flow channels 312 are communicated with the inside of the buffer chamber 1 104 and the buffer chamber 2 105 through two air suction pipes 305 at corresponding positions, and one end of the two partitions 308 is installed with an electromagnet 309, and the two electromagnets 309 are electrically connected to the two trigger switches 205 respectively;

[0038] The buffer chamber 104, the buffer chamber 105 and the vacuum chamber 106 are evacuated step by step through the step-by-step exhaust mechanism, so that the external air pressure, the air pressure of the buffer chamber 104, the air pressure of the buffer chamber 105 and the air pressure of the vacuum chamber 106 are successively reduced in a step-by-step manner. In this way, when the retaining ring 101, the retaining ring 102 and the retaining ring 103 do not apply too much pressure to the PCB board, the small pressure difference is not enough to allow the air to pass through the gap between the sealing ring 107 and the PCB board and enter the inner side of the vacuum chamber 106. Therefore, when no large pressure is applied to the PCB board, good sealing can be ensured, and indentations at the edge of the PCB board caused by excessive pressure can be effectively prevented.

[0039] Furthermore, the ratio of the inner diameters of the fixed flow channel 307 and the two movable flow channels 312 is equal to the volume ratio of the vacuum chamber 106, the buffer chamber 105, and the buffer chamber 104 (combined with Figure 3 and Figure 8 );

[0040] When the fixed flow channel 307 and the two movable flow channels 312 are respectively connected to the vacuum chamber 106, the buffer chamber 105 and the buffer chamber 1 104, with the operation of the vacuum pump 301, it can be ensured that the speed of evacuating the inside of the vacuum chamber 106 is greater than the speed of evacuating the buffer chamber 105 and the buffer chamber 1 104, which is beneficial to maintain the pressure difference between the adjacent buffer chamber 1 104 air pressure, the buffer chamber 2 105 air pressure and the vacuum chamber 106 unchanged, thereby improving stability.

[0041] Furthermore, two lower pressure electric cylinders 6 are installed on the upper side of the upper plate 2, and the telescopic ends of the two lower pressure electric cylinders 6 are slidably connected with sliders 7, and the lower sides of the two sliders 7 are fixed with suspension rods 8 extending to the outside, and the lower ends of the two suspension rods 8 are fixed to the upper side of the sealing cover 3, and the upper sides of the two sliders 7 are elastically connected to the telescopic ends of the lower pressure electric cylinders 6 through buffer springs 9;

[0042] The telescopic ends of the two lower pressure electric cylinders 6 are extended synchronously to drive the sealing cover 3 to move vertically downward. When the retaining ring 101, the retaining ring 102 and the retaining ring 103 on the lower side of the sealing cover 3 contact the upper edge of the PCB board, the PCB board will give the sealing cover 3 a reaction force through the retaining ring 101, the retaining ring 102 and the retaining ring 103. The reaction force is transmitted to the two buffer springs 9 through the two suspension rods 8 and the two sliders 1 7. The two buffer springs 9 can buffer the reaction force. During the compression of the buffer springs 9, the two lower pressure electric cylinders 6 have enough time to stop extending to prevent the telescopic ends of the two lower pressure electric cylinders 6 from continuing to apply thrust to the sealing cover 3, causing the PCB board to be subjected to a greater impact, thereby preventing indentations at the edge of the PCB board.

[0043] Furthermore, a plurality of pressing cylinders 401 are installed on the lower side of the sealing cover 3, a pressing plate 402 is fixed to the telescopic end of the plurality of pressing cylinders 401, and a cushion 403 is provided on the lower side of the pressing plate 402;

[0044] When the vacuum chamber 106 reaches a certain vacuum level, the telescopic ends of the multiple pressing cylinders 401 extend to drive the pressing plate 402 to move downward. The pressing plate 402 moves downward to apply pressure to the PCB, thereby pressing the PCB.

[0045] Furthermore, a guide cylinder 404 is fixed at the center position on the upper side of the pressing plate 402, and a pre-compression rod 405 is slidably connected to the inner side of the guide cylinder 404. The upper end of the pre-compression rod 405 is elastically connected to the inner upper end of the guide cylinder 404 through a pre-compression spring 406, and the lower end of the pre-compression rod 405 is lower than the lower side height of the retaining ring 101.

[0046] When the sealing cover 3 drives the retaining ring 101, the retaining ring 102 and the retaining ring 103 to move downward, since the lower end height of the pre-compression rod 405 is lower than the lower side height of the retaining ring 101, the lower end of the pre-compression rod 405 will contact the upper side of the PCB board before the sealing ring 107. Under the action of the pre-compression spring 406, the pre-compression rod 405 can pre-apply a certain pressure to the center of the PCB board. In this way, when vacuuming, the center of the PCB board can be prevented from bulging upward and deforming due to the decrease in air pressure inside the vacuum chamber 106, thereby ensuring the flatness of the PCB board.

[0047] Furthermore, two positioning cylinders 4 are symmetrically installed at two diagonal positions on the upper side of the lower plate 1, and positioning angle blocks 5 are fixed to the telescopic ends of the two positioning cylinders 4;

[0048] The telescopic ends of the two positioning cylinders 4 are controlled to extend, driving the two positioning angle blocks 5 to merge, and the two positioning angle blocks 5 are pressed against the diagonal corners of the PCB board respectively, so that the PCB board can be positioned and fixed at the same time.

[0049] Working principle: When in use, place the PCB board to be pressed on the upper side of the lower plate 1, then control the telescopic ends of the two positioning cylinders 4 to extend, drive the two positioning angle blocks 5 to merge, and the two positioning angle blocks 5 are pressed against the diagonal corners of the PCB board respectively, so that the PCB board can be positioned and fixed at the same time, so that the PCB board is located directly below the sealing cover 3;

[0050] Then, the telescopic ends of the two lower pressure electric cylinders 6 are controlled to extend synchronously to drive the sealing cover 3 to move vertically downward. When the retaining ring 101, the retaining ring 102 and the retaining ring 103 on the lower side of the sealing cover 3 contact the upper edge of the PCB board, the PCB board will give the sealing cover 3 a reaction force through the retaining ring 101, the retaining ring 102 and the retaining ring 103. The reaction force is transmitted to the two buffer springs 9 through the two suspension rods 8 and the two sliders 1 7. The two buffer springs 9 can buffer the reaction force. During the compression of the buffer springs 9, the two lower pressure electric cylinders 6 have enough time to stop extending, preventing the telescopic ends of the two lower pressure electric cylinders 6 from continuing to apply thrust to the sealing cover 3, causing the PCB board to be subjected to a large impact, thereby preventing indentations from being caused at the edge of the PCB board.

[0051] When the sealing cover 3 drives the retaining ring 101, the retaining ring 102 and the retaining ring 3 103 to move downward, since the lower end height of the pre-compression rod 405 is lower than the lower side height of the retaining ring 101, the lower end of the pre-compression rod 405 will contact the upper side of the PCB board before the sealing ring 107. Under the action of the pre-compression spring 406, the pre-compression rod 405 can pre-apply a certain pressure to the center of the PCB board. In this way, when vacuuming, it can prevent the center of the PCB board from bulging upward and deforming due to the reduction of air pressure inside the vacuum chamber 106, thereby ensuring the flatness of the PCB board. When the inside of the vacuum chamber 106 reaches a certain vacuum degree, the telescopic ends of the multiple pressing cylinders 401 are controlled to extend and drive the pressing plate 402 to move downward. The pressing plate 402 moves downward to apply pressure on the PCB board, thereby achieving the effect of quickly pressing the PCB board.

[0052] When the sealing cover 3 drives the lower retaining ring 101, retaining ring 2 102, and retaining ring 3 103 to press on the upper edge of the PCB board, the vacuum pump 301 of the step-by-step exhaust mechanism is operated, wherein the fixed valve column 306 of the step-by-step conduction mechanism is fixed, so the fixed flow channel 307 always connects the vacuum chamber 106 with the air inlet end of the vacuum pump 301 through the air outlet pipe 304 and the air intake pipe 305 at the corresponding position, and the two movable valve columns 311 are located at the specified position under the action of the two reset springs 310, so that As a result, the two active flow channels 312 and the other two suction pipes 305 are not aligned, so the active flow channels 312 and the suction pipes 305 are not connected, so the two active flow channels 312 are not connected with the buffer chamber 104 and the buffer chamber 2 105. At this time, when the vacuum pump 301 is running, it only draws out the air inside the vacuum chamber 106, so that the inside of the vacuum chamber 106 forms a negative pressure state. As the air pressure inside the vacuum chamber 106 decreases, the air pressure inside the buffer chamber 2 105 will be higher than the air pressure inside the vacuum chamber 106, so that the buffer chamber A certain pressure difference is generated between the second buffer chamber 105 and the vacuum chamber 106. The relatively higher pressure air inside the second buffer chamber 105 pushes the sensing piston plate 202 in the corresponding pressure difference sensing mechanism. The sensing piston plate 202 moves to compress the balance spring 204. When the pressure difference between the second buffer chamber 105 and the vacuum chamber 106 reaches a certain value, the sensing piston plate 202 triggers the trigger switch 205. When the trigger switch 205 is triggered, the circuit is turned on for the electromagnet 309 in the middle. The electromagnet 309 in the middle When the power is turned on, the electromagnetic suction force is generated to attract a movable valve column 311 at the corresponding position, so that the movable valve column 311 moves, and the movable valve column 311 drives the movable flow channel 312 inside it to move, so that the movable flow channel 312 connects an air intake pipe 305 connected to the second buffer chamber 105 with an air outlet pipe 304 at the corresponding position, thereby connecting the second buffer chamber 105 with the air inlet end of the vacuum pump 301. At this time, the operation of the vacuum pump 301 can simultaneously evacuate the inside of the second buffer chamber 105 and the vacuum chamber 106;

[0053] Similarly, as the air pressure in the buffer chamber 105 gradually decreases, a pressure difference is gradually formed between the buffer chamber 104 and the buffer chamber 105. The air with a higher pressure in the buffer chamber 104 pushes the sensing piston plate 202 of the other pressure difference sensing mechanism to move, thereby triggering another trigger switch 205. The other trigger switch 205 conducts the circuit of another electromagnet 309. The other electromagnet 309 is energized to generate an electromagnetic suction force to attract another active valve column 311 to move, thereby causing the inside of the other active valve column 311 to The active flow channel 312 connects the buffer chamber 104 with the air inlet end of the vacuum pump 301. At this time, the vacuum pump 301 can simultaneously evacuate the inside of the buffer chamber 104, the buffer chamber 2 105, and the vacuum chamber 106. Because a certain pressure difference is always maintained between the buffer chamber 104 and the buffer chamber 2 105, and between the buffer chamber 2 105 and the vacuum chamber 106, the two active flow channels 312 will be aligned and connected with the two suction pipes 305 respectively, so that the buffer chamber 104, the buffer chamber 2 105, and the vacuum chamber 106 can be evacuated at the same time. The vacuum chamber 106 is evacuated, so that a certain pressure difference can be maintained between the buffer chamber 1 104 and the buffer chamber 2 105, and between the buffer chamber 2 105 and the vacuum chamber 106, so that the pressure between the buffer chamber 1 104, the buffer chamber 2 105, and the vacuum chamber 106 is reduced in sequence, and the vacuum degree is increased in sequence. When a certain vacuum degree is reached inside the vacuum chamber 106, the pressure difference between the outside and the vacuum chamber 106 can be shared by the retaining ring 101, the retaining ring 2 102, and the retaining ring 3 103, so that the external air pressure, the buffer chamber 104, the buffer chamber 2 105, and the vacuum chamber 106 are always maintained. The air pressure in the first chamber 104, the air pressure in the second buffer chamber 105, and the air pressure in the vacuum chamber 106 are successively decreased in a step-by-step manner. In this way, when the first retaining ring 101, the second retaining ring 102, and the third retaining ring 103 do not exert too much pressure on the PCB board, the small pressure difference is not enough to allow the air to enter the inner side of the vacuum chamber 106 through the gap between the sealing ring 107 and the PCB board. Therefore, when no large pressure is exerted on the PCB board, good sealing can be ensured, and indentations at the edge of the PCB board caused by excessive pressure can be effectively prevented.

[0054] The above description enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A PCB circuit board vacuum quick press, comprising an upper plate (2) and a lower plate (1) arranged one above the other, characterized in that: A sealing cover (3) is movably provided below the upper plate (2); a retaining ring 1 (101), a retaining ring 2 (102), and a retaining ring 3 (103) are concentrically fixed at the lower edge of the sealing cover (3); a buffer cavity 1 (104) and a buffer cavity 2 (105) are formed between the retaining ring 1 (101), the retaining ring 2 (102), and the retaining ring 3 (103); and a vacuum cavity (106) is formed between the retaining ring 3 (103) and the sealing cover (3); Two pressure difference sensing mechanisms are arranged on the outside of the sealing cover (3), respectively connecting the buffer chamber 1 (104) and the buffer chamber 2 (105), and connecting the buffer chamber 2 (105) and the vacuum chamber (106), and the two pressure difference sensing mechanisms respectively detect the air pressure between the buffer chamber 1 (104) and the buffer chamber 2 (105), and between the buffer chamber 2 (105) and the vacuum chamber (106); A stepped air extraction mechanism is arranged on the outside of the sealing cover (3), and the stepped air extraction mechanism extracts the insides of the buffer chamber 1 (104), the buffer chamber 2 (105), and the vacuum chamber (106) to different vacuum degrees; The pressure difference sensing mechanism comprises a sensing cylinder (201), the inner side of the sensing cylinder (201) is slidably connected to a sensing piston plate (202), one end of the sensing piston plate (202) is elastically connected to an inner end of the sensing cylinder (201) via a balance spring (204), and a trigger switch (205) is inserted and installed at an inner end of the sensing cylinder (201) away from the sensing piston plate (202); The step-type exhaust mechanism comprises a vacuum pump (301) installed on the outside of the sealing cover (3); the air inlet end of the vacuum pump (301) is connected to a collecting pipe (302); three air outlet pipes (304) are inserted on one side of the collecting pipe (302); one end of the three air outlet pipes (304) is connected to a reversing pipe (303); one side of the reversing pipe (303) is provided with an air intake pipe (305) at a position corresponding to each air outlet pipe (304); one end of the three air intake pipes (305) is respectively connected to the inner side of the buffer chamber 1 (104), the buffer chamber 2 (105), and the vacuum chamber (106); and a step-by-step conduction mechanism is provided on the inner side of the reversing pipe (303); The step-by-step conduction mechanism comprises a fixed valve column (306) fixed to one end of the inner side of the reversing tube (303) and two partitions (308) fixed to the inner side of the reversing tube (303) at a middle position, a fixed flow channel (307) is provided inside the fixed valve column (306), the fixed flow channel (307) is communicated with the inside of the vacuum chamber (106) through an air suction pipe (305) at a corresponding position, one end of the two partitions (308) are elastically connected to movable valve columns (311) respectively through return springs (310), and the two movable valve columns (311) are slidably connected to the inner side of the reversing tube (303), and The two movable valve posts (311) are each provided with a movable flow channel (312) inside, and the two movable flow channels (312) are respectively connected to the inside of the buffer chamber 1 (104) and the buffer chamber 2 (105) through two suction pipes (305) at corresponding positions. An electromagnet (309) is installed at one end of the two partitions (308), and the two electromagnets (309) are respectively electrically connected to the two trigger switches (205). The ratio of the inner diameters between the fixed flow channel (307) and the two movable flow channels (312) is equal to the ratio of the volumes between the vacuum chamber (106), the buffer chamber 2 (105), and the buffer chamber 1 (104).

2. The PCB circuit board vacuum quick press according to claim 1, characterized in that: The two ends of one of the sensing tubes (201) are in communication with the inner sides of buffer chamber one (104) and buffer chamber two (105) through two buffer chamber connecting tubes (203), and the two ends of the other sensing tube (201) are in communication with the inner sides of buffer chamber two (105) and the vacuum chamber (106) through the two buffer chamber connecting tubes (203).

3. The PCB circuit board vacuum quick press according to claim 1, characterized in that: Two downward pressure electric cylinders (6) are installed on the upper side of the upper plate (2), and the telescopic ends of the two downward pressure electric cylinders (6) are slidably connected to sliders (7), and the lower sides of the two sliders (7) are fixed with suspension rods (8) extending to the outside, and the lower ends of the two suspension rods (8) are fixed to the upper side of the sealing cover (3), and the upper sides of the two sliders (7) are elastically connected to the telescopic ends of the downward pressure electric cylinders (6) through buffer springs (9).

4. The PCB circuit board vacuum quick press according to claim 1, characterized in that: A plurality of pressing cylinders (401) are installed on the lower side of the sealing cover (3), a pressing plate (402) is fixed to the telescopic ends of the plurality of pressing cylinders (401), and a soft cushion (403) is provided on the lower side of the pressing plate (402).

5. The PCB circuit board vacuum quick press machine according to claim 4, characterized in that: A guide cylinder (404) is fixed at a central position on the upper side of the pressing plate (402), and a pre-compression rod (405) is slidably connected to the inner side of the guide cylinder (404). The upper end of the pre-compression rod (405) is elastically connected to the inner upper end of the guide cylinder (404) via a pre-compression spring (406), and the height of the lower end of the pre-compression rod (405) is lower than the height of the lower side of the retaining ring (101).

6. The PCB circuit board vacuum quick press according to claim 1, characterized in that: The lower sides of the retaining ring 1 (101), retaining ring 2 (102) and retaining ring 3 (103) are all wrapped with sealing rings (107).

7. The PCB circuit board vacuum quick press according to claim 1, characterized in that: Two positioning cylinders (4) are symmetrically mounted at two diagonal positions on the upper side of the lower plate (1), and positioning angle blocks (5) are fixed to the telescopic ends of the two positioning cylinders (4).

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