A water-cooled pressure head on a mobile phone display bonding device

Abstract

The present invention belongs to the technical field of mobile phone display screen manufacturing, and in particular, is a water-cooled pressure head on a mobile phone display screen bonding device, comprising two water-cooled pressure caps, a pressure head mounting block is provided on the side close to each other of the two water-cooled pressure caps, the pressure head mounting blocks are fixedly connected to the two water-cooled pressure caps, a cutter head is fixedly mounted on the pressure head mounting block, end caps are fixedly mounted on both sides of the pressure head mounting block, the two end caps are respectively in contact with the two sides of the two water-cooled pressure caps, and a first cooling water pipe is fixedly mounted on the same side of the two end caps. The present invention avoids the situation in which the electronic circuit contact and mechanical connection are poor due to the material rebound caused by the withdrawal of the pressure head under high temperature during the FPC electronic circuit bonding process.

Description

Technical Field

[0001] The invention relates to the technical field of mobile phone display screen manufacturing, and in particular to a water-cooling pressure head on mobile phone display screen bonding equipment. Background Art

[0002] Bonding heads are widely used in the equipment for the bonding process of mobile phone screen liquid crystal display modules (LCMs). That is, the components that assemble the liquid crystal display, drive circuit, FPC (Flexible Printed Circuit), backlight and other structural parts together. The mechanical connection and electrical conduction between the liquid crystal glass and the drive circuit and FPC in the liquid crystal display are the core parts of LCM production. The production process of liquid crystal glass and FPC is the FOG (Film On Glass) bonding process, that is, the FPC is mounted on the glass panel. The process equipment in the FOG bonding process will use this type of head. The following is the basic process flow:

[0003] 1. ACF pre-lamination: paste ACF of specified length on the ITO end of the LCD glass or the pins of the FPC that need to be bonded;

[0004] 2. Pre-bonding: Use the auxiliary image system on the FOG bonding machine to align the pins of the FPC and the ITO end of the liquid crystal glass, and pre-press to form a preliminary connection;

[0005] 3. Main bonding: Under higher temperature and pressure, the pre-bonded LCM products are subjected to main bonding. The electrical connection between FPC and liquid crystal glass is achieved through the deformation of ACF conductive particles and the rupture of the insulating layer. At the same time, the two different materials, FPC and liquid crystal glass, are connected together through the polymerization and hardening of ACF glue at high temperature to provide sufficient mechanical connection strength.

[0006] The fully automatic COG bonding machine is mainly composed of three units: ACF (anisotropic conductive adhesive or anisotropic conductive film), pre-pressing and main pressing. The main pressing unit is also called the main pressing bonding device, which is used to complete the back-end process of the display screen, namely the main pressing stage. Specifically, the main function of the pressure head of the main pressing bonding device is to provide a movement in the Z-axis direction, so as to apply a force of about 150-300N on the buffer silicone tape, and then transfer it to the glass substrate and IC.

[0007] In order to make the circuits between the IC and the glass substrate well connected, during this pressing stage, the pressing head temperature needs to be as high as 200-420 degrees. The temperature of the heat insulation board rises sharply, and this heat will be transferred to the parts above the pressing head. The expansion coefficient of the product material is unstable under the heating state and the influence of the ambient temperature, which directly affects the product yield.

[0008] In the existing LCM product process similar to FOG bonding, the temperature of the pressure head is kept at a high temperature (such as 180 degrees - 360 degrees) when the pressure head is bonding the product. The pressure head is withdrawn in a hot state, and the material has not been completely cooled. Therefore, after the material is heated, it needs to be cooled naturally. The product material rebounds under high temperature, causing poor contact of the electronic pin circuit, which not only reduces the circuit connection strength and force between the FPC and the liquid crystal glass, but also causes the electrode pins of the FPC and the liquid crystal glass to produce induced open circuits due to the particle situation. The existing LCM products bonded by the FOG process have serious quality risks. Therefore, a water-cooled pressure head on the mobile phone display bonding equipment is proposed. Summary of the invention

[0009] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a water-cooling pressure head on a mobile phone display screen bonding device.

[0010] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a water-cooled pressure head on a mobile phone display bonding device, comprising two water-cooled pressure covers, a pressure head mounting block is provided on the side where the two water-cooled pressure covers are close to each other, the pressure head mounting blocks are fixedly connected to the two water-cooled pressure covers, a cutter head is fixedly mounted on the pressure head mounting block, end covers are fixedly mounted on both sides of the pressure head mounting block, the two end covers are respectively in contact with the two sides of the two water-cooled pressure covers, and a first cooling water pipe is fixedly mounted on the same side of the two end covers.

[0011] Preferably, a second cooling water pipe is fixedly installed on one side of the two end covers close to each other, and both ends of the second cooling water pipe are respectively fixedly connected to the two first cooling water pipes.

[0012] Preferably, the ends of the two first cooling water pipes away from the two end covers are fixedly mounted with a same fixing plate.

[0013] Preferably, an induction heating coil is fixedly mounted on one side of the fixing plate.

[0014] Preferably, temperature sensing probes are fixedly mounted on the two end covers, and the two temperature sensing probes are fixedly connected to the fixing plate.

[0015] Preferably, a connecting plate is fixedly mounted on the fixing plate, and two ceramic thermal insulation pads are fixedly mounted on the bottom of the connecting plate, and both of the two ceramic thermal insulation pads are fixedly connected to the pressure head mounting block.

[0016] Preferably, two ceramic heat-insulating rings are fixedly mounted on the top of the connecting plate, and connecting blocks are fixedly mounted on the tops of the two ceramic heat-insulating rings.

[0017] Preferably, a first plug and a second plug are welded to both of the end covers.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: first, the device is equipped with a water-cooled pressure cover, a cutter head, a first plug, an induction heating coil, an end cover, a second plug, a first cooling water pipe, a temperature sensing probe, a connecting plate, a ceramic heat insulating ring, a connecting block, a second cooling water pipe, a pressure head mounting block, a ceramic heat insulating pad, and a fixing plate. The medium frequency controller is started to preheat the cutter head so that the temperature reaches the process required temperature (160-280°C). After the temperature reaches the set value, the Z-axis pressure mechanism is started. The Z-axis pressure mechanism above the cutter head moves vertically downward at a uniform speed. The Z-axis pressure mechanism drives the device as a whole to move downward through the connecting block, thereby driving the cutter head to move downward, so that the cutter head is bonded. The cutter head passes through the buffer silica gel. It is pressed on the product, and then the Z-axis pressing mechanism is kept stationary and the temperature of the pressing head is kept stable within the process requirements. When the bonding time is up, the intermediate frequency controller is turned off, and cooling water is introduced into one of the first cooling water pipes. The cooling water enters the other first cooling water pipe through the second cooling water pipe and flows out. The cold water in the second cooling water pipe flows rapidly to quickly cool the cutter head to the lower limit (70-110℃); when the cutter head is cooled to the set lower line temperature, the bonding position of the product is also reduced to the temperature of the product material forming state (70-100℃), so as to control the thermal expansion and contraction of the material and the instability of the electronic circuit, thereby improving the product quality. Then the cutter head rises and returns to the standby position to complete a binding process.

[0019] The present invention avoids the situation in which the electronic circuit contact and mechanical connection are poor due to the material rebounding caused by the withdrawal of the pressure head under high temperature during the FPC electronic circuit bonding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention;

[0021] Figure 2 It is a schematic diagram of the side cross-sectional structure of the end cover and the pressure head mounting block in the present invention;

[0022] Figure 3 It is an exploded view of the present invention.

[0023] In the figure: 1. water-cooled pressure cover; 2. cutter head; 3. first plug; 4. induction heating coil; 5. end cover; 6. second plug; 7. first cooling water pipe; 8. temperature sensing probe; 9. connecting plate; 10. ceramic insulation ring; 11. connecting block; 12. second cooling water pipe; 13. pressure head mounting block; 14. ceramic insulation pad; 15. fixing plate. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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. Example

[0025] Please refer to Figure 1-3 The present invention provides a technical solution: a water-cooled pressure head on a mobile phone display screen bonding device, comprising two water-cooled pressure caps 1, a pressure head mounting block 13 is provided on the side of the two water-cooled pressure caps 1 close to each other, the pressure head mounting blocks 13 are fixedly connected to the two water-cooled pressure caps 1, a cutter head 2 is fixedly mounted on the pressure head mounting block 13, end caps 5 are fixedly mounted on both sides of the pressure head mounting block 13, the two end caps 5 are respectively in contact with the two sides of the two water-cooled pressure caps 1, and a first cooling water pipe 7 is fixedly mounted on the same side of the two end caps 5;

[0026] A second cooling water pipe 12 is fixedly installed on one side of the two end covers 5 close to each other, and both ends of the second cooling water pipe 12 are fixedly connected to the two first cooling water pipes 7 respectively. The ends of the two first cooling water pipes 7 away from the two end covers 5 are fixedly installed with the same fixing plate 15, and an induction heating coil 4 is fixedly installed on one side of the fixing plate 15. Temperature sensing probes 8 are fixedly installed on the two end covers 5, and the two temperature sensing probes 8 are fixedly connected to the fixing plate 15. A connecting plate 9 is fixedly installed on the fixing plate 15, and two ceramic heat insulation pads 14 are fixedly installed on the bottom of the connecting plate 9. Each ceramic insulation pad 14 is fixedly connected to the pressure head mounting block 13, two ceramic insulation rings 10 are fixedly installed on the top of the connecting plate 9, and the tops of the two ceramic insulation rings 10 are fixedly installed with a connecting block 11, and the first plug 3 and the second plug 6 are welded on the two end covers 5, through the water-cooled pressure cover 1, the cutter head 2, the first plug 3, the induction heating coil 4, the end cover 5, the second plug 6, the first cooling water pipe 7, the temperature sensing probe 8, the connecting plate 9, the ceramic insulation ring 10, the connecting block 11, the second cooling water pipe 12, the pressure head mounting block 13, the ceramic insulation pad 14, the fixing plate 1 5, start the intermediate frequency controller to preheat the cutter head 2, so that the temperature reaches the process requirement temperature of 160-280℃. After the temperature reaches the set value, start the Z-axis mechanism, and the Z-axis main pressing mechanism above the cutter head 2 moves vertically downward at a uniform speed. The Z-axis main pressing mechanism drives the device as a whole to move downward through the connecting block 11, thereby driving the cutter head 2 to move downward, so that the cutter head 2 is bonded. The cutter head 2 is indirectly pressed on the product through the buffer silicone, and then the Z-axis main pressing mechanism is kept stationary and the pressure head temperature is kept stable within the process requirement range. When the bonding time is up, turn off the intermediate frequency controller and send one of the Cooling water is introduced into the first cooling water pipe 7, and the cooling water flows into another first cooling water pipe 7 through the second cooling water pipe 12. The cold water in the second cooling water pipe 12 quickly cools the cutter head 2 to the lower limit (70-110°C); when the cutter head 2 is cooled to the set lower line temperature, the product bonding position part is also cooled to the product material shaping state temperature (70-100°C), so as to control the thermal expansion and contraction of the material and the instability of the electronic circuit, thereby improving the product quality. Then the cutter head 2 rises and returns to the standby position, completing a binding process. The present invention avoids the situation in which the electronic circuit contact and mechanical connection are poor due to the material rebound caused by the withdrawal of the pressure head under the high temperature state during the FPC electronic circuit bonding process.

[0027] In this embodiment, first, an intermediate frequency controller is provided on one side of the device, and the induction heating coil 4 is connected to the intermediate frequency controller. A Z-axis pressing mechanism is provided on the top of the device, and the connecting block 11 is fixedly connected to the Z-axis pressing mechanism. The intermediate frequency controller is started to preheat the cutter head 2 so that the temperature reaches the process required temperature (160-280°C). After the temperature reaches the set value, the Z-axis mechanism is started, and the Z-axis pressing mechanism above the cutter head 2 moves vertically downward at a uniform speed. The Z-axis pressing mechanism drives the device as a whole to move downward through the connecting block 11, thereby driving the cutter head 2 to move downward, so that the cutter head 2 is bonded, and the cutter head 2 is indirectly pressed on the product through the buffer silicone, and then the Z-axis pressing mechanism is kept stationary and Keep the temperature of the pressure head stable within the range of process requirements. When the bonding time is up, turn off the intermediate frequency controller, and introduce cooling water into one of the first cooling water pipes 7. The cooling water flows into the other first cooling water pipe 7 through the second cooling water pipe 12. The cold water in the second cooling water pipe 12 quickly cools the cutter head 2 to the lower limit (70-110°C). When the cutter head 2 is cooled to the set lower line temperature, the bonding position of the product is also cooled to the product material shaping state temperature (70-100°C), thereby achieving the purpose of controlling the thermal expansion and contraction of the material and the instability of the electronic circuit, thereby improving the product quality. Then the cutter head 2 rises and returns to the standby position, completing a binding process.

[0028] In this device, the cutter head 2 is made of YG12X tungsten steel and is vacuum heat treated, so that the heating deformation of the workpiece during use can be ignored, the surface finish reaches 0.4µm, and the parallelism reaches 0.001mm;

[0029] The first plug 3 and the second plug 6 are designed to be seamlessly welded with the end cover using stainless steel 316 to meet the requirements of repeated heating and cooling without water seepage;

[0030] The water-cooled gland 1 is used to cover the second cooling pipe 12 and the gland mounting block 13, so as to achieve cooling at the cutter head 2;

[0031] The end cover 5 is made of 316 stainless steel, and is used to fix the connection of the second cooling pipe 12 and the first cooling water pipe 7 and the installation of the temperature sensing probe;

[0032] The temperature sensing probe 8 is used to detect the temperature change during the heating and use of the pressure head, and the process temperature change process is realized through mutual adjustment between the temperature controller and the intermediate frequency controller;

[0033] The connecting plate 9 is used to fix the induction heating coil 4. The material is 6061 aluminum alloy. Since the connecting plate 9 is relatively close to the induction heating coil 4, the aluminum alloy is less affected by the eddy current and meets the strength requirements. In addition, it can be used as a heat sink to prevent heat from being transferred to the upper components.

[0034] The ceramic heat insulating ring 10 is made of ceramic material to reduce the heat conduction of the upper connecting plate during the heating process of the cutter head 2;

[0035] The ceramic heat-insulating pad 14 reduces the temperature transfer of the upper parts during the rapid heating of the cutter head 2.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A water-cooled pressure head on a mobile phone display screen bonding device, comprising two water-cooled pressure covers (1), characterized in that: A pressure head mounting block (13) is provided on the side of the two water-cooled pressure covers (1) close to each other, the pressure head mounting block (13) is fixedly connected to the two water-cooled pressure covers (1), a cutter head (2) is fixedly mounted on the pressure head mounting block (13), end covers (5) are fixedly mounted on both sides of the pressure head mounting block (13), the two end covers (5) are respectively in contact with the two sides of the two water-cooled pressure covers (1), a first cooling water pipe (7) is fixedly mounted on the same side of the two end covers (5), a second cooling water pipe (12) is fixedly mounted on the side of the two end covers (5) close to each other, and the second cooling water pipe (1 2) are respectively fixedly connected to the two first cooling water pipes (7), and the two first cooling water pipes (7) are fixedly installed with a same fixing plate (15) at one end away from the two end covers (5), and a connecting plate (9) is fixedly installed on the fixing plate (15), and two ceramic thermal insulation pads (14) are fixedly installed at the bottom of the connecting plate (9), and the two ceramic thermal insulation pads (14) are fixedly connected to the pressure head mounting block (13), and two ceramic thermal insulation rings (10) are fixedly installed on the top of the connecting plate (9), and the tops of the two ceramic thermal insulation rings (10) are fixedly installed with a connecting block (11).

2. The water-cooled pressure head on the mobile phone display screen bonding device according to claim 1, characterized in that: An induction heating coil (4) is fixedly mounted on one side of the fixing plate (15).

3. The water-cooled pressure head on the mobile phone display screen bonding device according to claim 1, characterized in that: A temperature sensing probe (8) is fixedly mounted on each of the two end covers (5), and each of the two temperature sensing probes (8) is fixedly connected to the fixing plate (15).

4. The water-cooled pressure head on the mobile phone display screen bonding device according to claim 1 is characterized in that: A first plug (3) and a second plug (6) are welded onto the two end covers (5).

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