Mini LED substrate vacuum pressing machine and control method

Abstract

The application relates to the technical field of circuit board production equipment, and discloses a Mini LED substrate vacuum pressing machine and a control method, wherein the Mini LED substrate vacuum pressing machine comprises a machine shell, a plurality of heating plates, a pressing support assembly and a controller; the plurality of heating plates are arranged in the pressing cavity in a vertical direction at intervals; the inside of the heating plate is provided with a heat-conducting oil pipeline and an electric heating component; the heat-conducting oil pipeline is formed with at least two U-shaped bending channels; the oil inlet is controlled through an electric control valve; the heating plate is connected with a plurality of temperature control probes; the pressing support assembly comprises a main hydraulic cylinder and an auxiliary pressure maintaining mechanism; the base of the auxiliary pressure maintaining mechanism is fixed to the output end of the main hydraulic cylinder; the upper end surface of the base is provided with a sliding groove; the bottom surface of the supporting plate is provided with a sliding block; the guide inclined surface of the sliding block is attached to the inclined surface of the wedge block; the wedge block is connected with an auxiliary hydraulic cylinder; the main hydraulic cylinder and the auxiliary hydraulic cylinder are connected to a hydraulic station; the electric control valve, the electric heating component, the temperature control probe and the hydraulic station are electrically connected to the controller.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of circuit board production equipment, in particular to a Mini LED substrate vacuum pressing machine and a control method. BACKGROUND

[0002] Mini LED, also known as sub-millimeter light-emitting diode, has a size of about 100 microns. Compared with traditional LED, the chip size of mini LED is smaller and the light-emitting angle is larger. Using mini LED for backlight display can achieve higher brightness, color gamut and contrast. Combined with the partition display technology, it can realize ultra-high-definition display screen. At present, mini LED backlight gradually penetrates into various fields such as large-size television, notebook and tablet, and with the increasing demand for application, the market potential of mini LED is very huge.

[0003] In the related art, the Mini LED substrate is usually pressed into one body with the bottom plate and the copper plate by using a vacuum pressing machine in production. Since the size of the mini LED chip is small, the performance requirement for the substrate is higher. The thermal stability and pressing force stability of the existing vacuum pressing machine cannot meet the production requirement and need to be improved. SUMMARY

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application provides a Mini LED substrate vacuum pressing machine, which can accurately control the temperature and improve the stability of the pressing force to meet the production requirement of Mini LED substrate.

[0005] The present application also provides a control method applied to the above-mentioned Mini LED substrate vacuum pressing machine.

[0006] The Mini LED substrate vacuum pressing machine according to the first aspect of the present application comprises a machine shell, a plurality of heating plates, a pressing support assembly and a controller, the inside of the machine shell is formed with a pressing cavity, the front side of the machine shell is provided with a movable door body to open or close the pressing cavity, and the pressing cavity is connected with a vacuumizing device through a pipeline; the plurality of heating plates are arranged in the pressing cavity in a vertical direction, the heating plates are in sliding connection with the machine shell, the inside of the heating plate is provided with a heat conducting oil pipeline and an electric heating component, the heat conducting oil pipeline is formed with at least two U-shaped curved channels, the electric heating component is filled in the area outside the heat conducting oil pipeline, the inlet of the heat conducting oil pipeline is provided with an electric control valve, the heating plate is connected with a plurality of temperature control probes, and the plurality of temperature control probes are distributed in a circumferential direction of the heating plate; the pressing support assembly is arranged on the bottom surface of the pressing cavity, the pressing support assembly comprises a main hydraulic cylinder and an auxiliary pressure maintaining mechanism, the main hydraulic cylinder is arranged in a vertical direction, the auxiliary pressure maintaining mechanism comprises a base, a support plate and a wedge, the base is fixed on the output end of the main hydraulic cylinder, the upper end surface of the base is provided with a sliding groove, the bottom surface of the support plate is provided with a sliding block, the sliding block and the wedge can slide in the sliding groove, the end of the sliding block is provided with a guide inclined surface, the inclined surface of the wedge is matched with the guide inclined surface, the wedge is connected with an auxiliary hydraulic cylinder, the auxiliary hydraulic cylinder is fixed to the base, the lowermost heating plate is fixed on the top surface of the support plate, and the main hydraulic cylinder and the auxiliary hydraulic cylinder are connected to a hydraulic station; the electric control valve, the electric heating component, the temperature control probe and the hydraulic station are electrically connected to the controller.

[0007] The Mini LED substrate vacuum pressing machine according to the first aspect of the present application has at least the following beneficial effects:

[0008] A group of bottom plates and copper plates are placed on each heating plate, the door body is closed, the pressing cavity is vacuumized through the vacuumizing device, the controller controls the electric control valve to be opened, the heat conducting oil enters the heat conducting oil pipeline of the heating plate to increase the temperature of the heating plate, the controller controls the electric heating component to be started, the temperature of the heating plate is increased to a set temperature and kept in a set temperature range, then the controller controls the hydraulic station to act, the main hydraulic cylinder pushes the auxiliary pressure maintaining mechanism and the lowermost heating plate to rise, so that the plurality of heating plates are stacked and clamp the plurality of groups of bottom plates and copper plates, then the auxiliary hydraulic cylinder pushes the wedge to move, the support plate is pushed to rise through the cooperation of the inclined surface, and the pressing force and the pressure maintaining are increased. The heating mode of the combination of the heat conducting oil and the electric heating component is beneficial to accurately control the temperature, the auxiliary pressure maintaining mechanism is used to increase the pressing force and the stability of the pressing force, the performance of the pressed substrate is improved, and the production demand of the Mini LED is met.

[0009] According to some embodiments of the first aspect of the present application, the heating plate has two electric heating components, which are distributed on both sides of the heat conduction oil pipeline.

[0010] According to some embodiments of the first aspect of the present application, the electric heating component is provided with a U-shaped bending part, which is located in the inner region of the bending channel.

[0011] According to some embodiments of the first aspect of the present application, the support plate is connected with a plurality of pressure sensors, which are distributed along the circumference of the support plate.

[0012] According to some embodiments of the first aspect of the present application, the auxiliary pressure maintaining mechanism has two wedge blocks, which are distributed on both sides of the sliding block, and the sliding block is provided with two symmetrical guide inclined surfaces.

[0013] According to some embodiments of the first aspect of the present application, the upper end surface of the base is provided with a support groove, which is V-shaped, and the bottom surface of the support plate is provided with a support block, the shape of which matches that of the support groove, and the support block abuts against the inner wall of the support groove.

[0014] According to some embodiments of the first aspect of the present application, the bottom surface of the support plate is provided with a support part, which includes a cylinder and a plurality of rib plates evenly distributed around the circumference of the cylinder, and the sliding block and the support block are an integral structure and fixed to the support part.

[0015] According to some embodiments of the first aspect of the present application, the outer wall of the cabinet is connected with a locking mechanism, which includes a locking seat and a wrench, the locking seat is detachably connected to the cabinet, the locking seat is provided with a rotating shaft, the end of the wrench is provided with a cam, the cam is rotationally connected to the rotating shaft, and the cam can abut against the side of the door body away from the cabinet.

[0016] The control method according to the second aspect of the present application is applied to the Mini LED substrate vacuum pressing machine according to the first aspect of the present application, and the control method includes the following steps:

[0017] S100, after the bottom plate and the copper plate are loaded, the controller controls the electric control valve to open, the heat conduction oil enters the heat conduction oil pipeline of the heating plate to increase the temperature of the heating plate, the controller controls the electric heating component to start, and the temperature of the heating plate is increased to a set temperature and kept within a set temperature range;

[0018] S200, the controller controls the hydraulic station to start, the hydraulic station drives the main hydraulic cylinder to start, the main hydraulic cylinder pushes the auxiliary pressure maintaining mechanism and the lowermost heating plate to move upward, so that a plurality of heating plates are stacked and clamped a plurality of groups of bottom plates and copper plates;

[0019] S300, the hydraulic station drives the auxiliary hydraulic cylinder of the auxiliary pressure maintaining mechanism to start, the auxiliary hydraulic cylinder pushes the wedge block to move in the chute, and in turn pushes the sliding block and the support plate to rise, increases the pressing force, and stabilizes the pressing force in a set range.

[0020] According to some embodiments of the second aspect of the application, in the S100 step, the heat conducting oil raises the temperature of the heating plate to more than 95% of the set temperature, the electric heating component raises the temperature of the heating plate to the set temperature, the controller receives signals of a plurality of temperature control probes, and the controller precisely controls the temperature of the heating plate through an integrated PID controller.

[0021] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0022] Additional aspects and advantages of the application will become apparent and appreciated through review of the following detailed description, taken in conjunction with the accompanying drawings, in which:

[0023] Figure 1 A schematic diagram of a Mini LED substrate vacuum pressing machine according to an embodiment of the first aspect of the application;

[0024] Figure 2 A schematic diagram of a Mini LED substrate vacuum pressing machine according to an embodiment of the first aspect of the application;

[0025] Figure 3 A schematic diagram of an electric heating plate according to some embodiments of the first aspect of the application;

[0026] Figure 4 A schematic diagram of the distribution of heat conducting oil pipes and electric heating components inside an electric heating plate according to some embodiments of the first aspect of the application;

[0027] Figure 5 A schematic diagram of an auxiliary pressure maintaining mechanism according to some embodiments of the first aspect of the application Figure 1 ;

[0028] Figure 6 A schematic diagram of an auxiliary pressure maintaining mechanism according to some embodiments of the first aspect of the application Figure 2 ;

[0029] Figure 7The exploded view of the locking mechanism in some embodiments of the first aspect of the application;

[0030] Figure 8 The sealing structure of the cabinet and the door body in some embodiments of the first aspect of the application.

[0031] The reference signs are as follows:

[0032] Cabinet 100, pressing cavity 101, door body 110, sealing rib 111, locking mechanism 120, locking seat 121, wrench 122, rotating shaft 123, cam 124, sealing gasket 130;

[0033] Heating plate 200, heat conduction oil pipeline 201, electric heating component 202;

[0034] Pressing support assembly 300, main hydraulic cylinder 310, auxiliary pressure maintaining mechanism 320, base 321, support plate 322, wedge block 323, sliding groove 324, sliding block 325, guide inclined surface 3251, auxiliary hydraulic cylinder 326, support groove 327, support block 328, support part 329. DETAILED DESCRIPTION

[0035] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0036] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as a limitation of the present application, which indicates or implies that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application.

[0037] In the description of the present application, if the first, second, etc. are described, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the sequence of technical features indicated.

[0038] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be broadly understood, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0039] It can be understood that the reference Figures 1 to 6The first aspect of the present invention provides a Mini The LED substrate vacuum laminating machine includes a housing 100, multiple heating plates 200, a laminating support assembly 300, and a controller. The housing 100 contains a laminating cavity 101, which serves as the space for laminating production substrates. To facilitate loading and unloading, a movable door 110 is provided on the front side of the housing 100 to open or close the laminating cavity 101. The laminating cavity 101 is connected to a vacuum pump via pipelines. The vacuum pump is used to evacuate the laminating cavity 101 to obtain a set vacuum level. The door 110 is typically a sliding door. Rollers are provided at the upper end of the housing 100, and a slide rail is provided at the upper end of the door 110. The slide rail rolls on the rollers, thereby moving the door 110 to open or close the laminating cavity 101. A frame can be provided on the side of the housing 100, with multiple rollers of corresponding heights on the frame. When the laminating cavity 101 is opened, the door 110 can be moved to the frame for temporary storage.

[0040] like Figure 2 As shown, multiple heating plates 200 are arranged vertically at intervals in the pressing cavity 101. The heating plates 200 are slidably connected to the housing 100. This can be achieved by installing vertical slide rails on the inner wall of the housing 100, with the heating plates 200 connected to the slide rails via sliding members. The sliding members can be held at any height on the slide rails and can move along the slide rails when subjected to thrust. Alternatively, special locking devices can be used to help position the heating plates 200. Alternatively, a specially designed carriage can be used, with multiple heating plates 200 connected to the carriage, which is then pushed into the pressing cavity 101 for use. Inside the heating plates 200, there are heat transfer oil pipes 201 and electric heating components 202. The heat transfer oil pipes 201 are used for the flow of heat transfer oil and form at least two U-shaped curved channels, resulting in a longer flow path for the heat transfer oil and helping the heating plates 200 heat up. The electric heating element 202 fills the area outside the heat transfer oil pipeline 201, which helps to balance heating and improve the heating speed. An electric control valve is installed at the inlet of the heat transfer oil pipeline 201. The heating plate 200 is connected to multiple temperature control probes. The multiple temperature control probes are distributed at intervals along the circumference of the heating plate 200. The multiple temperature control probes can be arranged in a ring, or in two rings, a rectangle with a ring inside, or other shapes.

[0041] The pressing support assembly 300 is arranged on the bottom surface of the pressing cavity 101, and the pressing support assembly 300 comprises a main hydraulic cylinder 310 and an auxiliary pressure maintaining mechanism 320. The main hydraulic cylinder 310 is arranged vertically, and the auxiliary pressure maintaining mechanism 320 comprises a base 321, a support plate 322 and a wedge block 323. The base 321 is fixed on the output end of the main hydraulic cylinder 310. The upper end surface of the base 321 is provided with a sliding groove 324. The bottom surface of the support plate 322 is provided with a sliding block 325. The sliding block 325 and the wedge block 323 can slide in the sliding groove 324. The end of the sliding block 325 is provided with a guide inclined surface 3251. The inclined surface of the wedge block 323 is matched with the guide inclined surface 3251. The wedge block 323 is connected with an auxiliary hydraulic cylinder 326. The auxiliary hydraulic cylinder 326 is fixed to the base 321. The lowermost heating plate 200 is fixed on the top surface of the support plate 322. The main hydraulic cylinder 310 and the auxiliary hydraulic cylinder 326 are connected to the hydraulic station. The electric control valve, the electric heating component 202, the temperature control probe and the hydraulic station are electrically connected to the controller.

[0042] The operation process of the Mini LED substrate vacuum pressing machine is as follows: a group of bottom plate and copper plate is placed on each heating plate 200. The door body 110 is closed, and the pressing cavity 101 is vacuumized by the vacuumizing equipment. The controller controls the electric control valve to open. The heat conducting oil enters the heat conducting oil pipeline 201 of the heating plate 200 to increase the temperature of the heating plate 200. The controller controls the electric heating component 202 to start. The heating power of the electric heating component 202 is controlled by the information fed back by the plurality of temperature control probes. The temperature of the heating plate 200 is accurately increased to the set temperature and kept within the set temperature range (for example, within 0.2°). The bottom plate and the copper plate are synchronously heated in this process. Then the controller controls the hydraulic station to act. The main hydraulic cylinder 310 pushes the auxiliary pressure maintaining mechanism 320 and the lowermost heating plate 200 to rise, so that the plurality of heating plates 200 are stacked and clamp a plurality of groups of bottom plate and copper plate. At this time, the bottom plate and the copper plate have been preliminarily clamped to prevent the displacement of the bottom plate and the copper plate. Then the auxiliary hydraulic cylinder 326 pushes the wedge block 323 to move. The support plate 322 is pushed to rise by the cooperation of the inclined surface, so as to increase the pressing force and the pressure maintaining. The controller accurately controls the output hydraulic oil pressure to accurately control the pressing force. The hydraulic station is driven by a servo motor, which can accurately control the output hydraulic oil pressure. The heating mode of the combination of the heat conducting oil and the electric heating component 202 can accurately control the temperature and stability of the heating plate in cooperation with the temperature control probe. The auxiliary pressure maintaining mechanism 320 increases the pressing force and the stability of the pressing force to improve the performance of the substrate and meet the production requirements of Mini LED.

[0043] As Figure 4As shown, in some embodiments of the first aspect of the present application, the heating plate 200 has two electric heating components 202 distributed on both sides of the heat conduction oil pipeline 201, mainly considering that after the heat conduction oil pipeline 201 is designed to be curved, the heating plate 200 still has a lot of empty space, and the two electric heating components 202 are used to fill both sides of the heat conduction oil pipeline 201, reducing the empty space, which helps to improve the temperature uniformity and heating speed of the heating plate 200. The heating plate 200 can use electric heating wires, electric heating tubes, graphene heating components, etc. As shown in the figure, Figure 3 As shown, in order to facilitate processing, the heating plate 200 can be divided into two plate parts, and after the containing grooves of the heat conduction oil pipeline 201 and the electric heating component 202 are processed, the two plate parts are assembled into one, such as welding, bolt fixing, etc.

[0044] Referring to Figure 3 In some embodiments of the first aspect of the present application, for the U-shaped curved channel of the heat conduction oil pipeline 201, the electric heating component 202 is also provided with a U-shaped curved part, which is located in the inner region of the curved channel, further increasing the heating density, which helps to improve the temperature uniformity and heating speed of the heating plate 200.

[0045] It can be understood that the support plate 322 is connected with a plurality of pressure sensors, which are distributed along the circumference of the support plate 322, and can be arranged in a circular ring, two circular rings, a rectangular ring, or various shapes, which can be designed according to the shape and area size of the support plate 322.

[0046] Referring to Figure 5 and Figure 6 In some embodiments of the first aspect of the present application, the auxiliary pressure maintaining mechanism 320 uses two wedge blocks 323, which are distributed on the opposite sides of the sliding block 325, and the corresponding sliding block 325 is provided with two symmetrical guide inclined surfaces 3251. The two wedge blocks 323 push the sliding block 325 to rise from both sides, and the stress is relatively balanced and stable. In actual operation, the auxiliary hydraulic cylinder 326 pushes the wedge block 323 to move, and the inclined surface of the wedge block 323 is in close contact with the guide inclined surface 3251, thereby pushing the sliding block 325 to rise. By controlling the output force of the auxiliary hydraulic cylinder 326, the distance of the sliding block 325 rising can be controlled, thereby adjusting the pressing force. In addition, the output force of the auxiliary hydraulic cylinder 326 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 323 or more wedge blocks 323 can also be used, and a wedge block 323 can also be used, and the side of the sliding block 325 away from the guide inclined surface 3251 is in sliding fit with the base 321, such as through a linear module connection, through a slide rail connection, etc.

[0047] Referring to Figure 5And Figure 6 In some embodiments of the first aspect of the present application, the upper end surface of the base 321 is further provided with a support groove 327, the support groove 327 is V-shaped, the bottom surface of the support plate 322 is provided with a support block 328, the shape of the support block 328 matches the shape of the support groove 327, when the sliding block 325 is not pushed up by the wedge block 323, the support block 328 abuts against the inner wall of the support groove 327, so that the base 321 supports the sliding block 325 and the support plate 322, and when the auxiliary hydraulic cylinder 326 is in the retracted state, the wedge block 323 is separated from the sliding block 325, the gravity of the sliding block 325 and the support plate 322 will not be transmitted to the auxiliary hydraulic cylinder 326, avoiding crushing the auxiliary hydraulic cylinder 326.

[0048] As Figure 6 shown, in some embodiments of the first aspect of the present application, the bottom surface of the support plate 322 is provided with a support part 329, the support part 329 includes a cylindrical body and a plurality of rib plates uniformly distributed around the cylindrical body, considering that the area of the support plate 322 is larger, by setting a plurality of rib plates, the structural strength and rigidity of the support plate 322 can be greatly increased, which is conducive to stably supporting the heating plate 200. The sliding block 325 and the support block 328 are of an integral structure and are fixed to the support part 329, which improves the stable supporting force and pushes the heating plate 200 up and applies a pressing force.

[0049] Referring to Figure 1 In some embodiments of the first aspect of the present application, the outer wall of the cabinet 100 is connected with a locking mechanism 120, and the shape of the door body is rectangular, usually two locking mechanisms 120 are arranged on each side of the door body, and the two locking mechanisms 120 on the same side correspond to the upper and lower ends of the door body 110. The locking mechanism 120 includes a locking seat 121 and a wrench 122, the locking seat 121 is detachably connected to the cabinet 100, the locking seat 121 is provided with a rotating shaft 123, the end of the wrench 122 is provided with a cam 124, the cam 124 is rotationally connected to the rotating shaft 123, by rotating the wrench 122, the part with larger radius of the cam 124 is rotated to abut against the side of the door body 110 away from the cabinet 100, thereby pushing the door body 110 to press against the side of the cabinet 100, so as to be connected tightly, improve the sealing performance, and help the vacuumizing of the pressing cavity 101.

[0050] It can be understood that in order to facilitate the movement of the door body 110, the locking mechanism 120 can be disassembled as a whole, and a positioning pin can be arranged on the outer wall of the cabinet 100, and the locking seat 121 is provided with a positioning hole matched with the positioning pin. After the door body 110 is moved to close the pressing cavity 101, the locking seat 121 is installed on the positioning pin, and then the wrench 122 is turned to lock. Since the force of the door body on the locking mechanism 120 is perpendicular to the positioning pin, the locking mechanism 120 can be fixed. Of course, bolts, buckles or other detachable structures can also be arranged on the outer wall of the cabinet 100 to fix the locking mechanism 120. When moving the door body 110, two locking mechanisms 120 on one side of the door body 110 can be disassembled, which is convenient to operate. In addition, the locking seat 121 can also be hinged to the outer wall of the cabinet 100. When the door body 110 is moved, the locking seat 121 is turned to avoid the door body 110, which is convenient to operate.

[0051] As shown in Figure 8 The labyrinth seal structure is arranged between the cabinet 100 and the door body 110, and the sealing gasket 130 is fixed on the side surface of the cabinet 100. The two sides of the sealing gasket 130 are protruding cylindrical ribs, and the door body 110 is provided with a plurality of sealing edges 111 arranged at intervals. The sealing edges 111 are inserted into the grooves of the sealing gasket 130, and a plurality of grooves are located between the two cylindrical ribs, thereby forming a labyrinth seal. Under the pushing of the cam 124, the door body 110 can be in close contact with the sealing gasket 130, the sealing edges 111 are inserted into the grooves of the sealing gasket 130, and the sealing performance is improved, which is beneficial to the vacuumization of the pressing cavity 101, helps to improve the vacuum degree, reduces the influence of gas on the pressing, and makes the combination of the bottom plate and the copper plate more closely, which is beneficial to improve the performance of the produced MiniLED substrate.

[0052] The embodiment of the second aspect of the application proposes a control method, which is applied to the MiniLED substrate vacuum pressing machine of the first aspect embodiment. The control method comprises the following steps:

[0053] S100, after a plurality of bottom plates and copper plates are fed, the door body 110 is moved to close the pressing cavity 101, the pressing cavity 101 is vacuumized by a vacuumizing device, a high vacuum environment is obtained, a controller controls an electric control valve to open, and heat conducting oil enters the heat conducting oil pipeline 201 of the heating plate 200 to improve the temperature of the heating plate 200. The controller controls the electric heating component 202 to start, and the temperature of the heating plate 200 is raised to a set temperature and kept within a set temperature range (such as plus or minus 0.2°).

[0054] S200, the controller controls the hydraulic station to start, the hydraulic station outputs hydraulic oil, first drives the main hydraulic cylinder 310 to start, the main hydraulic cylinder 310 pushes the auxiliary pressure maintaining mechanism 320 and the lowermost heating plate 200 upwards, so that the plurality of heating plates 200 are stacked and clamped a plurality of groups of bottom plates and copper plates, at this time, a smaller pressing force is applied to the plurality of heating plates 200, and the inlet and outlet ports of the main hydraulic cylinder 310 can be closed to fix the position of the auxiliary pressure maintaining mechanism 320;

[0055] S300, the auxiliary hydraulic cylinder 326 of the auxiliary pressure maintaining mechanism 320 is driven by the hydraulic station to start, the auxiliary hydraulic cylinder 326 pushes the wedge block 323 to move in the sliding groove 324, and then pushes the sliding block 325 and the supporting plate 322 to rise, increases the pressing force, and stabilizes the pressing force in a set range, by controlling the output pressure of the hydraulic station, the output force of the auxiliary hydraulic cylinder 326 is stabilized in a certain range, and the stability of the pressing process is improved.

[0056] In some embodiments of the second aspect of the application, in the step S100, the heat conducting oil raises the temperature of the heating plate 200 to more than 95% of the set temperature, and then the temperature of the heating plate 200 is raised to the set temperature by using the electric heating component 202.

[0057] Further, in order to maintain the temperature of the heating plate 200 in a set temperature range, the controller receives signals of a plurality of temperature control probes, and the controller accurately controls the temperature of the heating plate 200 by using an integrated PID controller, so that the temperature of the heating plate 200 is maintained in a set temperature range (such as ±0.2°). Wherein u(t) is the output of the controller, e(t) is the control deviation, that is, the difference between the expected value and the actual value, 、 And Respectively, the proportional coefficient, the integral coefficient and the differential coefficient are determined according to the running data of the system. In the equation, The proportional part reacts immediately according to the current value of the deviation, the larger the deviation, the larger the output, which helps to quickly reduce the deviation; The integral of the deviation is adjusted by accumulating the deviation to adjust the output, which helps to eliminate the steady-state error; The output is adjusted according to the rate of change of the deviation, which helps to reduce the overshoot and speed up the system response. The algorithm of the PID controller is easy to implement and debug, has good stability and robustness, and has certain adaptability to parameter changes and measurement noise of the system. The system response speed is fast, the control precision is high, and there are many adjustable parameters, which can be adjusted according to actual needs.

[0058] In the step S100, the temperature of the heating plate 200 from the start of the electric heating component 202 to the temperature reaching the set temperature range is the temperature rising stage, in which the power of the electric heating component 202 is raised to satisfy the equation: Y=K*arctanX, where Y is the power, X is the time (0-10 seconds), and K is the proportional coefficient, which is determined according to the different specifications of the base plate and the copper plate. In the temperature rising stage, the temperature of the heating plate 200 increases rapidly to approach the set temperature, and after reaching the maximum time (10 seconds), the temperature holding stage is entered, in which the temperature of the heating plate 200 is adjusted by the PID controller to keep the temperature of the heating plate 200 within the set temperature range.

[0059] In the step S300, after the auxiliary hydraulic cylinder 326 is started, the pressing force value is detected by the multiple pressure sensors on the support plate 322, the pressing force is increased to exceed the set range, and then the pressing force is decreased to be within the set range. The upper limit of the pressing force exceeding the set range is not more than 5%, and the time is 2 seconds. For example, if the set range of the pressing force is 100-110 kN, the pressing force is first increased to 113 kN, and after 2 seconds, the output force of the auxiliary hydraulic cylinder 326 is decreased, and the pressing force is decreased to be within the set range.

[0060] The embodiments of the present application are described in detail above with reference to the drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the present application.

Claims

1. A vacuum press-bonding machine for a mini LED substrate, characterized by comprising: The application relates to a pressing machine. The machine shell is internally provided with a pressing cavity, the front side of the machine shell is provided with a movable door body for opening or closing the pressing cavity, the pressing cavity is connected with a vacuumizing device through a pipeline, the side surface of the machine shell is fixedly provided with a sealing pad, the two side surfaces of the sealing pad are provided with protruding cylindrical convex strips, the door body is provided with a plurality of spaced sealing ribs, the sealing ribs are inserted into grooves of the sealing pad, and a plurality of the grooves are arranged between the two cylindrical convex strips to form a labyrinth seal. A plurality of heating plates are arranged in the pressing cavity in a vertical direction, the heating plates are in sliding connection with the machine shell, the inside of the heating plate is provided with a heat-conducting oil pipeline and an electric heating component, the heat-conducting oil pipeline is formed with at least two U-shaped bending channels, the electric heating component is filled in the area outside the heat-conducting oil pipeline, the inlet of the heat-conducting oil pipeline is provided with an electric control valve, the heating plate is connected with a plurality of temperature control probes which are distributed in a circumferential direction of the heating plate; heat-conducting oil enters the heat-conducting oil pipeline of the heating plate to raise the temperature of the heating plate to more than 95% of the set temperature, then the electric heating component raises the temperature of the heating plate to the set temperature, the power of the electric heating component rises to meet the equation Y=K*arctanX, wherein Y is the power, X is the time, the value range of X is 0-10, the unit is second, K is a proportional coefficient, and K is determined according to different specifications of the bottom plate and the copper plate, then after 10 seconds, the controller receives signals of the plurality of temperature control probes, and the temperature of the heating plate is adjusted by a PID controller to keep the temperature of the heating plate in a range of plus or minus 0.2 degrees of the set temperature. A pressing support assembly is arranged on the bottom surface of the pressing cavity, the pressing support assembly comprises a main hydraulic cylinder and an auxiliary pressure maintaining mechanism, the main hydraulic cylinder is arranged in a vertical direction, the auxiliary pressure maintaining mechanism comprises a base, a support plate and four wedge blocks, the base is fixed on the output end of the main hydraulic cylinder, the upper end surface of the base is provided with a sliding groove, the bottom surface of the support plate is provided with a sliding block, the sliding block and the wedge blocks can slide in the sliding groove, the end of the sliding block is provided with a guide inclined surface, the inclined surface of the wedge block can be attached to the guide inclined surface, the wedge block is connected with an auxiliary hydraulic cylinder, the auxiliary hydraulic cylinder is fixed on the base, the four wedge blocks are distributed in a circumferential direction of the base, the lowermost heating plate is fixed on the top surface of the support plate, the main hydraulic cylinder and the auxiliary hydraulic cylinder are connected to a hydraulic station, and the support plate is connected with a plurality of pressure sensors which are distributed in a circumferential direction of the support plate. The electric control valve, the electric heating component, the temperature control probe and the hydraulic station are electrically connected to the controller.

2. The Mini LED substrate vacuum press machine of claim 1, wherein, The heating plate has two electric heating components which are distributed on the two sides of the heat-conducting oil pipeline.

3. The Mini LED substrate vacuum lamination machine of claim 2, wherein, The electric heating component is provided with a U-shaped bending part which is arranged in the inner area of the bending channel.

4. The Mini LED substrate vacuum press machine of claim 1, wherein, The upper end surface of the base is provided with a support groove, the support groove is V-shaped, the bottom surface of the support plate is provided with a support block, 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.

5. The Mini LED substrate vacuum lamination machine of claim 4, wherein, The bottom surface of the support plate is provided with a support part, the support part includes a cylindrical body and a plurality of rib plates evenly distributed circumferentially around the cylindrical body, the sliding block and the support block are an integral structure, and are fixed to the support part.

6. The Mini LED substrate vacuum lamination machine of claim 1, wherein, The outer wall of the shell is connected with a locking mechanism, the locking mechanism includes a locking seat and a wrench, the locking seat is detachably connected to the shell, the locking seat is provided with a rotating shaft, the end of the wrench is provided with a cam, the cam is rotationally connected to the rotating shaft, and the cam can abut against the side surface of the door body away from the shell.

7. A control method applied to the Mini LED substrate vacuum lamination machine according to any one of claims 1 to 6, characterized in that, The control method comprises the following steps: S100, after the bottom plate and the copper plate are fed, the controller controls the electric control valve to be opened, the heat conducting oil enters the heat conducting oil pipeline of the heating plate, so as to improve the temperature of the heating plate, the controller controls the electric heating component to be started, the temperature of the heating plate is improved to the set temperature and is kept in the set temperature range, the controller receives the signals of the plurality of temperature control probes, the controller accurately controls the temperature of the heating plate through the integrated PID controller, and the control equation of the PID controller is as follows: Wherein u(t) is the output of the controller, e(t) is the control deviation, that is, the difference between the expected value and the actual value, K p , K i And K d are proportional coefficient, integral coefficient and differential coefficient respectively, which are determined according to the operation data of the system. S200, the controller controls the hydraulic station to start, the hydraulic station drives the main hydraulic cylinder to start, the main hydraulic cylinder pushes the auxiliary pressure maintaining mechanism and the lowermost heating plate to move upward, so that a plurality of heating plates are stacked and clamped a plurality of groups of bottom plates and copper plates; S300, the hydraulic station drives the auxiliary hydraulic cylinder of the auxiliary pressure maintaining mechanism to start, the auxiliary hydraulic cylinder pushes the wedge to move in the sliding groove, and in turn pushes the sliding block and the support plate to rise, increases the pressing force, and stabilizes the pressing force in the set range.

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