Multi-layer circuit board vacuum pressing equipment and control method

Abstract

The invention relates to the technical field of circuit board production equipment, and discloses multi-layer circuit board vacuum pressing equipment and a control method.The multi-layer circuit board vacuum pressing equipment comprises a machine base, a pressing device and a controller, a pressing cavity is formed in the machine base, the pressing cavity is connected with vacuumizing equipment through a pipeline, and an upper pressing plate and a lower pressing plate are arranged in the pressing cavity; the pressing device comprises a main oil cylinder and a pressure supplementing assembly, the pressure supplementing assembly comprises a seat body, a cover plate, a plurality of first pistons and a plurality of second pistons, output rods of the first pistons and output rods of the second pistons are connected with an upper pressing plate, the cover plate is connected to the upper end of the seat body, and a first oil inlet connector and a second oil inlet connector are connected to the cover plate. The first oil inlet connector and the second oil inlet connector are each provided with an electric control pressure regulating valve, the first oil inlet connector is communicated with the first annular groove, the second oil inlet connector is communicated with the second annular groove, an output rod of the main oil cylinder is connected with the cover plate, and the first oil inlet connector, the second oil inlet connector and the main oil cylinder are connected to a hydraulic station through pipelines.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board production equipment, and in particular to a multi-layer circuit board vacuum pressing device and a control method. Background Art

[0002] A multilayer circuit board has at least three conductive layers, two of which are on the outer surface and the rest are integrated inside. The electrical connection between the conductive layers is usually achieved through plated through holes on the cross section of the circuit board.

[0003] In the related art, a vacuum press is usually used to press the core board and the copper foil together, and a prepreg is placed between the core board and the copper foil as an adhesive. In order to improve production efficiency, multiple multi-layer circuit boards are usually stacked and pressed simultaneously, but the thickness of multiple multi-layer circuit boards is large, resulting in uneven distribution of pressing force, which affects product quality. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a multi-layer circuit board vacuum pressing device, which improves the distribution uniformity of the pressing force through structural improvement, which helps to improve product quality.

[0005] The present invention also provides a control method applied to the above-mentioned multi-layer circuit board vacuum pressing device.

[0006] According to the first aspect of the present invention, a multilayer circuit board vacuum pressing device comprises a machine base, a pressing device and a controller, wherein the machine base has a pressing chamber, the front and rear sides of the machine base are provided with movable door bodies to open or close the pressing chamber, the pressing chamber is connected to a vacuum pump through a pipeline, an upper pressing plate and a lower pressing plate are arranged in the pressing chamber; the pressing device is connected to the machine base, the pressing device comprises a main oil cylinder and a pressure compensation component, the pressure compensation component comprises a seat body, a cover plate, a plurality of first pistons and a plurality of second pistons, the seat body is provided with a plurality of first hydraulic holes matching the first pistons, a plurality of second hydraulic holes matching the second pistons, the plurality of first hydraulic holes are distributed along the circumference of the seat body, the plurality of second hydraulic holes are evenly distributed along the circumference of the seat body and are located inside the plurality of first hydraulic holes, each of the first hydraulic holes is installed with a first piston, and each of the second hydraulic holes is evenly distributed with a first piston. A second piston is installed in the pressure hole, the output rods of the first piston and the second piston are connected to the upper pressure plate, the upper end surface of the seat body is provided with a first annular groove and a second annular groove, the first annular groove is connected to a plurality of the first hydraulic holes, the second annular groove is connected to a plurality of the second hydraulic holes, the cover plate is connected to the upper end of the seat body and covers the first annular groove and the second annular groove, the cover plate is connected to a first oil inlet joint and a second oil inlet joint, the first oil inlet joint and the second oil inlet joint are both provided with an electrically controlled pressure regulating valve, the first oil inlet joint is connected to the first annular groove, the second oil inlet joint is connected to the second annular groove, the output rod of the master oil cylinder is connected to the cover plate, the first oil inlet joint, the second oil inlet joint and the master oil cylinder are connected to a hydraulic station through a pipeline; a controller, the vacuum pumping equipment, the electrically controlled pressure regulating valve and the hydraulic station are all electrically connected to the controller.

[0007] The multilayer circuit board vacuum pressing device according to the first embodiment of the present invention has at least the following beneficial effects: The substrate of the multi-layer circuit board is placed on the lower pressure plate, and the controller controls the hydraulic station to start. The hydraulic station inputs hydraulic oil into the main cylinder, and the main cylinder pushes the pressure-compensating assembly and the upper pressure plate downward until the upper pressure plate and the lower pressure plate cooperate to clamp the substrate of the multi-layer circuit board. Then the electronically controlled pressure regulating valve on the first oil inlet connector and the second oil inlet connector is opened, and hydraulic oil is injected into the multiple first hydraulic holes and the multiple second hydraulic holes. The multiple first pistons move synchronously, and the multiple second pistons also move synchronously to apply a large range of multi-point auxiliary pressing force to the upper pressure plate, thereby improving the uniformity of the distribution of the pressing force and helping to improve product quality.

[0008] According to some embodiments of the first aspect of the present invention, a plurality of the first hydraulic holes are arranged in a rectangular ring, a plurality of the second hydraulic holes are arranged in a circular ring, and a diameter of the first hydraulic holes is smaller than a diameter of the second hydraulic holes.

[0009] According to some embodiments of the first aspect of the present invention, two arc-shaped grooves are provided on the bottom surface of the cover plate, the lower sides of the two arc-shaped grooves are connected to the second annular groove, and the upper sides of the two arc-shaped grooves are connected to the second oil inlet joint.

[0010] According to some embodiments of the first aspect of the present invention, the pressing device has two master oil cylinders, which are distributed on the left and right sides of the second oil inlet joint, and the cover plate connects the two first oil inlet joints, which are distributed on the front and back sides of the second oil inlet joint.

[0011] According to some embodiments of the first aspect of the present invention, the two arc-shaped grooves are concentrically arranged, and a central angle thereof is greater than 150°.

[0012] According to some embodiments of the first aspect of the present invention, a rear opening is provided on the rear side of the base, the door body can cover the rear opening, and a plurality of exhaust fans are provided in the rear opening.

[0013] According to some embodiments of the first aspect of the present invention, the lower pressure plate is connected to an auxiliary pressure-maintaining mechanism, and the auxiliary pressure-maintaining mechanism includes a base, a support plate and a wedge block. The base is fixed to the machine base, and the lower pressure plate is fixed to the top surface of the support plate. The top surface of the base is provided with a slide groove, and the bottom surface of the support plate is provided with a slider. Both the slider and the wedge block can slide in the slide groove, and a guide slope is provided at the end of the slider. The slope of the wedge block can fit the guide slope, and the wedge block is connected to an auxiliary hydraulic cylinder, which is fixed to the base and connected to the hydraulic station.

[0014] According to some embodiments of the first aspect of the present invention, the auxiliary pressure maintaining mechanism has two wedge blocks, which are distributed on both sides of the slider, and the slider is provided with two symmetrical guide inclined surfaces. The top surface of the base is provided with a support groove, and the support groove is V-shaped. The bottom surface of the support plate is provided with a support block, and the shape of the support block matches the shape of the support groove, and the support block abuts against the inner wall of the support groove.

[0015] According to an embodiment of the second aspect of the present invention, a control method is provided, which is applied to the multilayer circuit board vacuum pressing device described in the embodiment of the first aspect, and the control method comprises the following steps: S100, after the substrate of the multilayer circuit board is loaded, the door is closed, and the controller controls the vacuuming device to start, so as to vacuum the pressing chamber; S200, the controller controls the hydraulic station to start, the hydraulic station inputs hydraulic oil into the main oil cylinder, and the main oil cylinder pushes the pressure compensation assembly and the upper pressure plate to move downward until the upper pressure plate and the lower pressure plate cooperate to clamp the substrate of the multi-layer circuit board; S300, the controller controls the electronically controlled pressure regulating valve on the second oil inlet connector to open, and hydraulic oil is input into the second hydraulic hole to push the second piston, and the plurality of second pistons push the upper pressure plate to further tighten; S400, the controller controls the electronically controlled pressure regulating valve on the first oil inlet connector to open, and hydraulic oil is input into the first hydraulic hole to push the first piston, and the plurality of first pistons push the upper pressure plate to further tighten.

[0016] According to some embodiments of the second aspect of the present invention, in the step S300, the oil inlet pressure is controlled by the electronically controlled pressure regulating valve on the second oil inlet connector, and the pressure of the hydraulic oil entering the second hydraulic hole rises to more than 70% of the preset pressure value, maintains for 2 seconds, and then rises to the preset pressure value.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Additional aspects and advantages of the present invention will become apparent and readily understood from the following description of embodiments in conjunction with the accompanying drawings, in which: Figure 1 It is an exploded schematic diagram of a multi-layer circuit board vacuum pressing device according to an embodiment of the first aspect of the present invention; Figure 2 It is a schematic structural diagram of a pressing device in an embodiment of the first aspect of the present invention; Figure 3 for Figure 2 Schematic diagram of the disassembly of the middle pressing device Figure 1 ; Figure 4 for Figure 2 Schematic diagram of the disassembly of the middle pressing device Figure 2 ; Figure 5 Schematic diagram of the auxiliary pressure-maintaining mechanism in the first embodiment of the present invention Figure 1 ; Figure 6 Schematic diagram of the auxiliary pressure-maintaining mechanism in the first embodiment of the present invention Figure 2 .

[0019] The figures are as follows: The machine base 100, the pressing chamber 101, the door body 110, the upper pressing plate 120, the positioning protruding ring 121, the exhaust hole 122, the lower pressing plate 130, the end cover 140, and the exhaust fan 150; Pressing device 200, main oil cylinder 210; The pressure compensation assembly 300, the seat body 310, the first hydraulic hole 311, the second hydraulic hole 312, the first annular groove 313, the second annular groove 314, the cover plate 320, the first oil inlet joint 321, the second oil inlet joint 322, the arc groove 323, the first piston 330, and the second piston 340; The auxiliary pressure-maintaining mechanism 400 , the base 410 , the slide groove 411 , the support groove 412 , the support plate 420 , the slide block 421 , the guide slope 4211 , the support block 422 , the support portion 423 , the wedge block 430 , and the auxiliary hydraulic cylinder 440 . DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0022] In the description of the present invention, if there is a description of first and second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0023] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0024] It is understandable that, referring to Figures 1 to 4, the embodiment of the first aspect of the present invention proposes a multi-layer circuit board vacuum pressing device, including a machine base 100, a pressing device 200 and a controller. The machine base 100 has a pressing chamber 101, which is the place where the multi-layer circuit board is pressed. In order to facilitate operation and maintenance, the front and rear sides of the machine base 100 are provided with movable door bodies 110 to open or close the pressing chamber 101, which is convenient for operators to load and unload the multi-layer circuit board. The pressing chamber 101 is connected to a vacuum pump through a pipeline. The vacuum pump creates a low-pressure environment during the pressing process, thereby improving the pressing quality and efficiency. The vacuum pump can select various forms of vacuum pumps or powerful fans. In the pressing chamber, an upper pressing plate and a lower pressing plate are arranged, which are key components for realizing the pressing of circuit boards. An upper pressing plate 120 and a lower pressing plate 130 are arranged in the pressing chamber 101, and the multi-layer circuit board is pressed by the upper pressing plate 120 and the lower pressing plate 130. The pressing device 200 is located at the upper part of the machine base 100, and the machine base 100 is connected to a detachable end cover 140. The end cover 140 is installed at the upper end of the machine base 100 and covers the pressing device 200. The end cover 140 can provide positioning support for the main oil cylinder 210 of the pressing device 200, or the machine base 100 can be provided with a special bracket to provide positioning support for the main oil cylinder 210 of the pressing device 200.

[0025] The pressing device 200 includes a main oil cylinder 210 and a pressure-compensating assembly 300. The pressure-compensating assembly 300 includes a seat body 310, a cover plate 320, a plurality of first pistons 330 and a plurality of second pistons 340. The seat body 310 is provided with a plurality of first hydraulic holes 311 matching the first pistons 330 and a plurality of second hydraulic holes 312 matching the second pistons 340. The plurality of first hydraulic holes 311 are distributed along the circumference of the seat body 310. The plurality of second hydraulic holes 312 are evenly distributed along the circumference of the seat body 310 and are located inside the plurality of first hydraulic holes 311. A first piston 330 is installed in each first hydraulic hole 311 to form a No. 1 small hydraulic cylinder. A second piston 340 is installed in each second hydraulic hole 312 to form a No. 2 small hydraulic cylinder. The output rods of the first piston 330 and the second piston 340 are connected to the upper pressure plate 120. That is, the plurality of No. 1 small hydraulic cylinders and the plurality of No. 2 small hydraulic cylinders can both push the upper pressure plate 120.

[0026] The upper end surface of the seat body 310 is provided with a first annular groove 313 and a second annular groove 314. The first annular groove 313 is connected to the plurality of first hydraulic holes 311 to guide and distribute the hydraulic oil to the plurality of first hydraulic holes 311. The second annular groove 314 is connected to the plurality of second hydraulic holes 312 to guide and distribute the hydraulic oil to the plurality of second hydraulic holes 312. The cover plate 320 is connected to the upper end of the seat body 310 and covers the first annular groove 313 and the second annular groove 314. The cover plate 320 is connected to the first oil inlet joint 321 and the second oil inlet joint 322, the first oil inlet connector 321 and the second oil inlet connector 322 are both provided with an electrically controlled pressure regulating valve, through which the pressure of the input hydraulic oil can be accurately controlled, the first oil inlet connector 321 is connected to the first annular groove 313, the second oil inlet connector 322 is connected to the second annular groove 314, the output rod of the main oil cylinder 210 is connected to the cover plate 320, the first oil inlet connector 321, the second oil inlet connector 322 and the main oil cylinder 210 are connected to the hydraulic station through pipelines; the vacuum equipment, the electrically controlled pressure regulating valve and the hydraulic station are all electrically connected to the controller.

[0027] When the multi-layer circuit board vacuum pressing equipment is in operation, the operator first places the substrate of the multi-layer circuit board on the lower pressing plate 130, then closes the door body 110, and the controller controls the vacuum pumping equipment to start, and the air in the pressing chamber 101 is sucked out to form a high vacuum environment, so that the air between the substrates of the multi-layer circuit board is discharged to prevent the pressing from being affected. Then, the controller controls the hydraulic station to start, and the hydraulic station inputs hydraulic oil into the main oil cylinder 210, and the main oil cylinder 210 pushes the pressure-compensating assembly 300 and the upper pressing plate 120 to move downward until the upper pressing plate 120 and the lower pressing plate 130 cooperate to clamp the substrate of the multi-layer circuit board, and then the electric-controlled pressure regulating valve on the first oil inlet joint 321 and the second oil inlet joint 322 is opened, and hydraulic oil is injected into the multiple first hydraulic holes 311 and the multiple second hydraulic holes 312, and the multiple No. 1 small hydraulic cylinders are synchronously operated, and the multiple No. 2 small hydraulic cylinders are also synchronously operated to apply a large range of multi-point auxiliary pressing force to the upper pressing plate 120, improve the distribution uniformity of the pressing force, improve the pressing effect, and help improve product quality.

[0028] In the following embodiment of the present invention, in order to further improve the pressing effect, the arrangement of the multiple first hydraulic holes 311 is designed to be a rectangular ring, which is adapted to the rectangular body structure of the seat body 310 and is distributed close to the edge of the seat body 310, while the arrangement of the multiple second hydraulic holes 312 is a circular ring, which improves the uniformity of each and makes the distribution of the hydraulic holes more reasonable, which helps the hydraulic oil to flow evenly in the seat body, thereby achieving a more uniform pressing force distribution.

[0029] In some embodiments of the present invention, two arc grooves 323 are designed on the bottom surface of the cover plate 320. The lower side of the two arc grooves 323 is connected to the second annular groove 314, and the upper side is connected to the second oil inlet joint 322. The shape of the arc groove 323 helps to guide the rapid flow of hydraulic oil, so that the hydraulic oil can flow smoothly from the second oil inlet joint 322 to the second annular groove 314, and then evenly distributed to each second hydraulic hole 312. The above design not only improves the efficiency of the hydraulic system, but also helps to reduce the impact of the hydraulic oil flow process, and improves the stability and reliability of the pressing equipment. The two arc grooves 323 are concentrically arranged, and the central angle is greater than 150°, which can cover the area of ​​multiple second hydraulic holes 312.

[0030] In addition, the first oil inlet connector 321 and the first annular groove 313 may be directly connected, or a guide groove with matching shape may be designed to guide the flow of hydraulic oil.

[0031] In some embodiments of the present invention, in order to improve the stability and uniformity during the pressing process, the pressing device 200 is structurally equipped with two main oil cylinders 210. According to the rectangular structure of the seat body 310, the two main oil cylinders 210 are distributed on the left and right sides of the second oil inlet joint 322. The above layout helps to achieve uniform distribution of pressure, and the upper pressure plate 120 presses the multi-layer circuit board more evenly during the pressing process.

[0032] It is understandable that, referring to Figure 2 and Figure 3 The diameter of the first hydraulic hole 311 is designed to be smaller than the diameter of the second hydraulic hole 312, that is, the thrust of the No. 1 small hydraulic cylinder is smaller than the thrust of the No. 2 small hydraulic cylinder. The two main oil cylinders 210 are distributed on the left and right sides of the second oil inlet joint 322, and multiple No. 2 small hydraulic cylinders provide greater pressing force in the center, so that the pressing force distribution of the entire upper pressure plate 120 is more uniform.

[0033] At the same time, the cover plate 320 is connected to two first oil inlet connectors 321, and the two first oil inlet connectors 321 are distributed on the front and rear sides of the second oil inlet connector 322. The distribution method further enhances the balance of the hydraulic system, which is beneficial to improving the oil inlet speed and control accuracy.

[0034] In some embodiments of the present invention, the structure of the upper pressing plate 120 is optimized and designed so that the upper pressing plate 120 can help position the multi-layer circuit board during the pressing process and can also help to draw a vacuum. A positioning convex ring 121 protruding downward is specially designed around the upper pressing plate 120, and a space is formed inside the positioning convex ring 121. The space is specifically used to accommodate the multi-layer circuit board, and the shape and size match the multi-layer circuit board to help position it. Through the above structure, the multi-layer circuit board can be confined to the center position of the upper pressing plate 120, which helps to prevent displacement or sliding under high pressure, thereby ensuring the accuracy of pressing.

[0035] Moreover, the lower end surface of the positioning protruding ring 121 is provided with a plurality of air extraction holes 122, and the plurality of air extraction holes 122 are also connected to the vacuum pumping device. During the vacuum pumping process, the vacuum pumping device quickly extracts the air around the substrate of the multi-layer circuit board through the plurality of air extraction holes 122, which is conducive to the discharge of air between the substrates, helps to improve the bonding strength and pressing quality of the multi-layer circuit board, can reduce the formation of air bubbles, and ensure that the adhesive or material is evenly distributed between the circuit boards.

[0036] It is understood that in some embodiments of the first aspect of the present invention, Figure 1 As shown, the rear side of the base 100 is provided with a rear opening, and the door body 110 can cover the rear opening, and a plurality of exhaust fans 150 are provided in the rear opening. The multilayer circuit board needs to be heated during the lamination process. Usually, the upper pressing plate 120 and the lower pressing plate 130 are heated by an electric heating component, or the upper pressing plate 120 and the lower pressing plate 130 are connected to the positive and negative electrodes respectively, and short-circuited after clamping the multilayer circuit board substrate, and the resistance becomes larger, thereby generating heat to make the multilayer circuit board substrate, which is helpful for melting the semi-cured sheet. After the lamination is completed, the door bodies 110 on the front and rear sides are disassembled, and the lamination chamber 101 is exhausted by a plurality of exhaust fans 150, and the outside air is used to help the multilayer circuit board to cool down quickly, thereby improving production efficiency. Among them, it should be understood that the exhaust fan 150 can be fixed to the base 100 or be detachable. For example, the base 100 is provided with a snap-in position, and the shell of the exhaust fan 150 is fixed by the snap-in position. The exhaust fan 150 is installed when it is needed, so as to avoid the exhaust fan 150 bringing pollutants to the pressing cavity 101, which is beneficial to improving product quality.

[0037] In some embodiments of the present invention, the lower pressing plate 130 is connected to an auxiliary pressure maintaining mechanism 400, such as Figure 5 and Figure 6 As shown, the auxiliary pressure-maintaining mechanism 400 includes a base 410, a support plate 420 and a wedge block 430. The base 410 is fixed to the machine base 100. The upper end surface of the base 410 is provided with a slide groove 411. The bottom surface of the support plate 420 is provided with a slider 421. Both the slider 421 and the wedge block 430 can slide in the slide groove 411. The end of the slider 421 is provided with a guide inclined surface 4211. The inclined surface of the wedge block 430 fits the guide inclined surface 4211. The wedge block 430 is connected to an auxiliary hydraulic cylinder 440. The auxiliary hydraulic cylinder 440 is fixed to the base 410. The lower pressure plate 130 is fixed to the top surface of the support plate 420. The auxiliary hydraulic cylinder 440 is connected to the hydraulic station.

[0038] After the upper pressing plate 120 and the lower pressing plate 130 cooperate to clamp the substrate of the multi-layer circuit board, the electrically controlled pressure regulating valves on the first oil inlet connector 321 and the second oil inlet connector 322 are opened, and hydraulic oil is injected into the multiple first hydraulic holes 311 and the multiple second hydraulic holes 312. Multiple No. 1 small hydraulic cylinders act synchronously, and multiple No. 2 small hydraulic cylinders also act synchronously to apply a large range of multi-point auxiliary pressing forces to the upper pressing plate 120 to improve the uniformity of the distribution of the pressing force. Then the auxiliary hydraulic cylinder 440 is started, and the auxiliary hydraulic cylinder 440 pushes the wedge block 430 to move, and uses the cooperation of the inclined surface to push the support plate 420 up, increasing the pressing force and maintaining the pressure. The hydraulic station is driven by a servo motor, which can accurately control the output hydraulic oil pressure.

[0039] Reference Figure 5 and Figure 6 In some embodiments of the first aspect of the present invention, the auxiliary pressure-maintaining mechanism 400 uses two wedge blocks 430, and the two wedge blocks 430 are distributed on opposite sides of the slider 421. The corresponding slider 421 is provided with two symmetrical guiding inclined surfaces 4211. The two wedge blocks 430 push the slider 421 to rise from both sides, and the force is relatively balanced and stable. In actual operation, the auxiliary hydraulic cylinder 440 pushes the wedge block 430 to move, and the inclined surface of the wedge block 430 fits with the guiding inclined surface 4211, thereby pushing the slider 421 to rise. By controlling the output force of the auxiliary hydraulic cylinder 440, the rising distance of the slider 421 can be controlled, thereby adjusting the pressing force. The output force of the auxiliary hydraulic cylinder 440 is controlled by the hydraulic oil pressure output by the hydraulic station, so as to achieve the purpose of accurately controlling the pressing force and improving the stability of the pressing force. In addition, three wedge blocks 430 or more wedge blocks 430 may be used, or one wedge block 430 may be used, and the side of the slider 421 away from the guide slope 4211 is slidably matched with the base 410, such as connected by a linear module or a slide rail.

[0040] Reference Figure 5 and Figure 6 In some embodiments of the first aspect of the present invention, a support groove 412 is further provided on the upper end surface of the base 410, and the support groove 412 is V-shaped. A support block 422 is provided on the bottom surface of the support plate 420, and the shape of the support block 422 matches the shape of the support groove 412. When the slider 421 is not pushed up by the wedge block 430, the support block 422 abuts against the inner wall of the support groove 412, so that the base 410 supports the slider 421 and the support plate 420, and when the auxiliary hydraulic cylinder 440 is in a retracted state, the wedge block 430 is disengaged from the slider 421, and the gravity of the slider 421 and the support plate 420 will not be transmitted to the auxiliary hydraulic cylinder 440, thereby avoiding crushing the auxiliary hydraulic cylinder 440.

[0041] like Figure 6As shown, in some embodiments of the first aspect of the present invention, a support portion 423 is provided on the bottom surface of the support plate 420, and the support portion 423 includes a cylinder and a plurality of ribs uniformly distributed around the cylinder. Considering that the area of ​​the support plate 420 is large, the structural strength and rigidity of the support plate 420 can be greatly increased by providing a plurality of ribs, which is conducive to stably supporting the lower pressing plate 130. The slider 421 and the support block 422 are an integrated structure and are fixed to the support portion 423, providing a stable supporting force to push the heating plate 200 up and apply a pressing force.

[0042] The embodiment of the second aspect of the present invention provides a control method, which is applied to the multilayer circuit board vacuum pressing device of the first aspect of the present invention. The control method includes the following steps: S100, after the substrate of the multilayer circuit board is loaded, the door 110 is closed, and the controller controls the vacuum pumping device to start, and the pressing chamber 101 is vacuumed to obtain a high vacuum environment to exhaust the air between the substrates to prevent bubbles from affecting the pressing; S200, the controller controls the hydraulic station to start, and the hydraulic station inputs hydraulic oil into the main oil cylinder 210, and the main oil cylinder 210 pushes the pressure compensation assembly 300 and the upper pressing plate 120 to move downward until the upper pressing plate 120 and the lower pressing plate 130 cooperate to clamp the substrate of the multi-layer circuit board, which is the initial clamping and positioning, and provides a part of the pressing force; S300, the controller controls the electronically controlled pressure regulating valve on the second oil inlet connector 322 to open, and the hydraulic oil is input into the second hydraulic hole 312 to push the second piston 340, and the plurality of second pistons 340 push the upper pressure plate 120 to further tighten; S400, the controller controls the electronically controlled pressure regulating valve on the first oil inlet connector 321 to open, and the hydraulic oil is input into the first hydraulic hole 311 to push the first piston 330, and the multiple first pistons 330 push the upper pressure plate 120 to further tighten.

[0043] It can be understood that the hydraulic oil is first input into the second hydraulic hole 312, and then into the first hydraulic hole 311, that is, the multiple No. 2 small hydraulic cylinders are actuated first, and the multiple No. 1 small hydraulic cylinders are actuated later. This is mainly because the multiple second hydraulic holes 312 are located inside the multiple first hydraulic holes 311, and the order of applying the auxiliary pressing force is from the center of the multi-layer circuit board to the periphery of the multi-layer circuit board, which helps to drive away the bubbles inside the multi-layer circuit board, and also helps to drive the adhesive to flow from the center of the multi-layer circuit board to the periphery of the multi-layer circuit board, thereby improving the uniformity of the distribution of the adhesive, helping to improve the bonding effect, and improving product quality.

[0044] It is understandable that in some embodiments of the second aspect of the present invention, in step S300, the oil inlet pressure is controlled by the electronically controlled pressure regulating valve on the second oil inlet connector 322, and the pressure of the hydraulic oil entering the second hydraulic hole 312 first rises to more than 70% of the preset pressure value, is maintained for 2 seconds, and then rises to the preset pressure value. The use of multi-stage boost can reduce the impact on the multi-layer circuit board, avoid deformation or damage to the substrate, and help improve the lamination effect.

[0045] In step S300, the pressure of the hydraulic oil entering the second hydraulic hole 312 first rises to 70% of the preset pressure value. The pressure change during the rising process of the hydraulic oil satisfies the equation: Y=K*arctanX, where Y is pressure, X is time (range 0 to 10, unit is seconds), and K is a proportional coefficient, which is determined according to different specifications of the substrate. During the pressure increase process, the pressure of the hydraulic oil increases rapidly to close to 70% of the preset pressure value. After reaching the maximum time (10 seconds), it can basically reach 70% of the preset pressure value and then stay for 2 seconds.

[0046] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. Multilayer circuit board vacuum pressing equipment, characterized in that: include: A machine base, wherein the machine base has a pressing cavity, the front and rear sides of the machine base are both provided with movable doors to open or close the pressing cavity, the pressing cavity is connected to a vacuum pumping device through a pipeline, and an upper pressing plate and a lower pressing plate are arranged in the pressing cavity; A pressing device is connected to the machine base, the pressing device includes a main oil cylinder and a pressure compensation component, the pressure compensation component includes a seat body, a cover plate, a plurality of first pistons and a plurality of second pistons, the seat body is provided with a plurality of first hydraulic holes matching the first pistons, a plurality of second hydraulic holes matching the second pistons, the plurality of first hydraulic holes are distributed along the circumference of the seat body, the plurality of second hydraulic holes are evenly distributed along the circumference of the seat body and are located inside the plurality of first hydraulic holes, a first piston is installed in each of the first hydraulic holes, a second piston is installed in each of the second hydraulic holes, the output rods of the first piston and the second piston are connected to the upper pressing plate, The upper end surface of the seat body is provided with a first annular groove and a second annular groove, the first annular groove is connected to a plurality of the first hydraulic holes, the second annular groove is connected to a plurality of the second hydraulic holes, the cover plate is connected to the upper end of the seat body and covers the first annular groove and the second annular groove, the cover plate is connected to a first oil inlet joint and a second oil inlet joint, the first oil inlet joint and the second oil inlet joint are both provided with an electrically controlled pressure regulating valve, the first oil inlet joint is connected to the first annular groove, the second oil inlet joint is connected to the second annular groove, the output rod of the master oil cylinder is connected to the cover plate, and the first oil inlet joint, the second oil inlet joint and the master oil cylinder are connected to the hydraulic station through pipelines; A controller, wherein the vacuum pumping equipment, the electrically controlled pressure regulating valve and the hydraulic station are all electrically connected to the controller.

2. The multi-layer circuit board vacuum pressing equipment according to claim 1, characterized in that: A plurality of the first hydraulic holes are arranged in a rectangular ring, a plurality of the second hydraulic holes are arranged in a circular ring, and a diameter of the first hydraulic hole is smaller than a diameter of the second hydraulic hole.

3. The multi-layer circuit board vacuum pressing equipment according to claim 2, characterized in that: The bottom surface of the cover plate is provided with two arc-shaped grooves, the lower sides of the two arc-shaped grooves are connected to the second annular groove, and the upper sides of the two arc-shaped grooves are connected to the second oil inlet joint.

4. The multi-layer circuit board vacuum pressing device according to claim 3, characterized in that: The two arc-shaped grooves are arranged concentrically, and the central angle thereof is greater than 150°.

5. The multi-layer circuit board vacuum pressing equipment according to claim 1, characterized in that: A downwardly protruding positioning convex ring is arranged around the periphery of the upper pressing plate, and a space for accommodating a multi-layer circuit board is formed inside the positioning convex ring. A plurality of exhaust holes are arranged on the lower end surface of the positioning convex ring, and the exhaust holes are connected to the vacuum pumping equipment.

6. The multi-layer circuit board vacuum pressing device according to claim 1, characterized in that: A rear opening is arranged at the rear side of the machine base, the door body can cover the rear opening, and a plurality of exhaust fans are arranged in the rear opening.

7. The multi-layer circuit board vacuum pressing equipment according to claim 1, characterized in that: The lower pressure plate is connected to an auxiliary pressure-maintaining mechanism, which includes a base, a support plate and a wedge block. The base is fixed to the machine base, and the lower pressure plate is fixed to the top surface of the support plate. The top surface of the base is provided with a slide groove, and the bottom surface of the support plate is provided with a slider. Both the slider and the wedge block can slide in the slide groove, and a guide slope is provided at the end of the slider. The slope of the wedge block can fit the guide slope, and the wedge block is connected to an auxiliary hydraulic cylinder, which is fixed to the base and connected to the hydraulic station.

8. The multi-layer circuit board vacuum pressing device according to claim 7, characterized in that: The auxiliary pressure-maintaining mechanism has two wedge blocks, which are distributed on both sides of the slider. The slider is provided with two symmetrical guide inclined surfaces. The top surface of the base is provided with a support groove, which is V-shaped. The bottom surface of the support plate is provided with a support block, the shape of which matches the shape of the support groove, and the support block abuts against the inner wall of the support groove.

9. A control method, applied to a multi-layer circuit board vacuum pressing device as claimed in any one of claims 1 to 8, characterized in that: The control method comprises the following steps: S100, after the substrate of the multilayer circuit board is loaded, the door is closed, and the controller controls the vacuuming device to start, so as to vacuum the pressing chamber; S200, the controller controls the hydraulic station to start, the hydraulic station inputs hydraulic oil into the main oil cylinder, and the main oil cylinder pushes the pressure compensation assembly and the upper pressure plate to move downward until the upper pressure plate and the lower pressure plate cooperate to clamp the substrate of the multi-layer circuit board; S300, the controller controls the electronically controlled pressure regulating valve on the second oil inlet connector to open, and hydraulic oil is input into the second hydraulic hole to push the second piston, and a plurality of the second pistons push the upper pressure plate to further tighten; S400, the controller controls the electronically controlled pressure regulating valve on the first oil inlet connector to open, and hydraulic oil is input into the first hydraulic hole to push the first piston, and the first pistons push the upper pressure plate to further tighten.

10. The control method according to claim 9, characterized in that: In the step S300, the oil inlet pressure is controlled by the electronically controlled pressure regulating valve on the second oil inlet connector, and the pressure of the hydraulic oil entering the second hydraulic hole rises to more than 70% of the preset pressure value, is maintained for 2 seconds, and then rises to the preset pressure value.

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