A preparation method for improving the bilateral pin span tolerance of an LCD

Abstract

The present invention discloses a preparation method for improving the span tolerance of LCD bilateral pins. By reducing the thickness of the rack of a rack, leaving a gap between the lower surface of the front half of the push block of a pin-mounting machine and the upper surface of the rack, and adjusting the fixed height of the clamp of the electrical test frame and the conductive adhesive, the connection between the upper and middle parts of the pins and the connection between the middle and lower parts of the pins are ensured to avoid air and move freely during the entire preparation process, thereby preventing the pins from being deformed due to force during the preparation process, thereby ensuring the span between the bilateral pins of the LCD so that they can be accurately aligned with the solder holes reserved on the customer's PCB, reducing the difficulty of subsequent assembly, and facilitating the automation of assembly. The present invention only requires simple modification of existing LCD pin-mounting equipment and can fully utilize existing processes, that is, it can control the span tolerance of the LCD bilateral pins within a precision range of ±0.2mm.

Description

Technical Field

[0001] The present invention relates to the technical field of LCD (liquid crystal display), and in particular to a preparation method for improving the span tolerance of LCD bilateral pins. Background Art

[0002] One type of LCD connection involves connecting the LCD panel to pins. LCD pins are typically made of copper, a metal with high toughness and stability. During the pin installation process using LCD pin-mounting equipment, both the installation and electrical testing phases require external force to ensure reliable pin installation. However, due to the inherent properties of the pin material, strong external forces can easily cause the pins to deform. For LCD products with pins on both sides of the panel, this deformation increases the gap between the pins. This makes it difficult to insert the pins into the solder holes reserved on the customer's PCB during assembly, resulting in assembly difficulties. While traditional manual assembly methods can manually apply force to align the pin gap with the customer's PCB, the gradual replacement of manual assembly with fully automated machine assembly methods requires a higher tolerance for the pin gap between the two sides, from the traditional ±1.0mm to ±0.20mm. Otherwise, the LCD cannot be assembled onto the customer's PCB. Summary of the Invention

[0003] The present invention aims to solve the problem that the span tolerance of the bilateral pins of the existing LCD is difficult to meet the precision requirements of machine automated assembly, and provides a preparation method for improving the span tolerance of the bilateral pins of the LCD.

[0004] To solve the above problems, the present invention is achieved through the following technical solutions:

[0005] A preparation method for improving the span tolerance of LCD bilateral pins includes the following steps:

[0006] Step 1: Prepare a rolled pin tray, which consists of multiple F-shaped pins and connecting strips to connect the pins together. Each pin consists of three parts: a U-shaped upper part, an inclined middle part, and a vertical lower part. The upper end of the middle part is connected to the lower end of the upper part, and the lower end of the middle part is connected to the upper end of the lower part.

[0007] Step 2: Suspend each pin on the pin tray in turn on each comb tooth of the rack of the LCD pin mounting device, with the opening direction of the upper portion of all pins aligned with the opening direction of the comb teeth of the rack; the thickness of the comb teeth of the rack is less than the height of the middle portion of the pin, the lower edge of the upper portion of the pin is in contact with the upper surface of the comb teeth of the rack, the middle portion of the pin is embedded in the comb teeth of the rack, and the lower end of the middle portion of the pin is lower than the lower surface of the comb teeth of the rack;

[0008] Step 3. Place the LCD screen in front of the rack, with the upper openings of all the pins hanging on the rack facing the edge step of the LCD screen; set the push block of the LCD pin mounting machine behind the rack, with the lower surface of the rear half of the push block in contact with the upper surface of the rack, and a gap between the lower surface of the front half of the push block and the upper surface of the rack, and the front end of the push block in contact with the upper middle part of the back of the upper part of the pins; under the horizontal forward thrust of the push block, the upper openings of all the pins hanging on the rack are embedded in the edge step of the LCD screen, so that the pins are installed on the edge step of the LCD screen;

[0009] Step 4: The LCD pin cutting machine will cut off the connecting strip at the bottom of the pins installed on the edge of the LCD screen, so that each pin can be connected and conductive independently;

[0010] Step 5: Repeat steps 2-4 above to install pins on both sides of the LCD screen to obtain a prefabricated LCD.

[0011] Step 6. Fix the prefabricated LCD in the prepared electrical testing frame of the LCD; set the fixture of the electrical testing frame between the bilateral pins of the prefabricated LCD and abut against the inner surface of the bilateral pins of the prefabricated LCD, with the upper surface of the fixture being lower than the horizontal height of the connection between the middle and lower parts of the pins; set two conductive adhesives of the electrical testing frame on the outer sides of the bilateral pins of the prefabricated LCD and abut against the outer surface of the bilateral pins of the prefabricated LCD, with the upper surface of the two conductive adhesives being lower than the horizontal height of the connection between the middle and lower parts of the pins; use the electrical testing frame to test the performance of the connection between the LCD screen and the pins, and obtain the prepared LCD after the test passes.

[0012] In the above step 2, the thickness of the teeth of the rack is reduced from 3.0 mm to 1.5 mm.

[0013] In the above step 3, the gap between the lower surface of the front half of the push block and the upper surface of the rack is 0.2 mm.

[0014] In the above step 6, the height difference between the horizontal height of the upper surface of the clamp and the horizontal height of the connection between the middle and lower parts of the pin is 0.5mm, and the height difference between the horizontal height of the upper surfaces of the two conductive glues and the horizontal height of the connection between the middle and lower parts of their corresponding pins is 1.0mm.

[0015] Compared with the prior art, the present invention reduces the thickness of the rack, leaves a gap between the lower surface of the front half of the push block of the pin-mounting machine and the upper surface of the rack, and adjusts the fixed height of the fixture of the electrical test frame and the conductive adhesive to ensure that the connection between the upper and middle parts of the pins and the connection between the middle and lower parts of the pins are free from air and can move freely during the entire preparation process, thereby preventing the pins from being deformed due to force during the preparation process, thereby ensuring the span between the bilateral pins of the LCD so that they can be accurately aligned with the solder holes reserved on the customer's PCB, reducing the difficulty of subsequent assembly and facilitating the automation of assembly. The present invention only requires a simple modification of the existing LCD pin-mounting equipment and can fully utilize the existing process, that is, it can control the span tolerance of the bilateral pins of the LCD within a precision range of ±0.2mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of the pin tray.

[0017] Figure 2 Schematic diagram of the pins hanging on the rack, (a) existing solution, (b) the solution of the present invention.

[0018] Figure 3 Schematic diagram of the position relationship between the push block and the pin, (a) existing solution, (b) the solution of the present invention.

[0019] Figure 4 This is a schematic diagram of the fixture, conductive glue and pin positions of the electrical test frame.

[0020] Numbers in the figure: 1, pin, 1-1, upper part, 1-2, middle part, 1-3, lower part; 2, connecting bar; 3, LCD screen; 4, rack; 5, push block; 6-1, clamp; 6-2, conductive glue. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described below in detail with reference to specific examples and the accompanying drawings. It should be noted that directional terms mentioned in the examples, such as "upper," "lower," "center," "left," "right," "front," and "back," are merely references to the directions in the accompanying drawings. Therefore, the directions used are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0022] A preparation method for improving the span tolerance of LCD bilateral pins includes the following steps:

[0023] Step 1: Prepare a coiled tray of tube pins 1. This tray consists of multiple F-shaped tube pins 1 and a connecting strip 2 that connects them. Each tube pin 1 consists of three parts: a U-shaped upper portion 1-1, an inclined middle portion 1-2, and a vertical lower portion 1-3. The upper end of the middle portion 1-2 is connected to the lower end of the upper portion 1-1, and the lower end of the middle portion 1-2 is connected to the upper end of the lower portion 1-3. The lower end of the lower portion 1-3 is connected to the connecting strip 2.

[0024] During LCD fabrication, the upper portion 1-1 of the pin 1 is inserted into the edge step of the LCD screen 3. During LCD assembly, the lower portion 1-3 of the pin 1 is soldered to the customer's PCB.

[0025] Step 2: Hang each pin 1 on the pin 1 tray in turn on each comb tooth of the rack 4 of the LCD pin mounting device, and the opening direction of the upper part 1-1 of all pins 1 is consistent with the opening direction of the comb teeth of the rack 4; the thickness of the comb teeth of the rack 4 is less than the height of the middle part 1-2 of the pin 1, so that the lower edge of the upper part 1-1 of the pin 1 is in contact with the upper surface of the comb teeth of the rack 4, the middle part 1-2 of the pin 1 is embedded in the comb teeth of the rack 4, and the horizontal height of the lower end of the middle part 1-2 of the pin 1 is lower than the horizontal height of the lower surface of the comb teeth of the rack 4.

[0026] The thickness of the teeth of the rack 4 of the existing LCD pin mounting equipment is generally greater than the height of the middle portion 1-2 of the pin 1. Therefore, when the pin 1 is suspended in the teeth of the rack 4, the lower end of the middle portion 1-2 of the pin 1 will be higher than the lower surface of the teeth of the rack 4. Figure 2 As shown in (a). At this time, since the entire middle portion 1-2 and the upper half of the lower portion 1-3 of the pin 1 are also hidden within the teeth of the rack 4, that is, the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1 is hidden in the teeth of the rack 4 in the horizontal direction, its flexible and free movement is restricted. Therefore, when the lower portion 1-3 of the pin 1 is subjected to external horizontal force in subsequent processes, its stress will be concentrated at the intersection of the lower portion 1-3 of the pin 1 and the lower surface of the teeth of the rack 4. The reaction force of the teeth of the rack 4 directly causes the lower portion 1-3 of the pin 1 to deform, making it impossible to ensure the span between the pins 1 on both sides of the LCD.

[0027] In the present invention, the thickness of the teeth of the rack 4 of the LCD pin mounting device is smaller than the height of the middle portion 1-2 of the pin 1. Thus, when the pin 1 is suspended in the teeth of the rack 4, the lower end of the middle portion 1-2 of the pin 1 will be lower than the lower surface of the teeth of the rack 4. Figure 2As shown in (b). At this time, since only the upper half of the middle part 1-2 of the pin 1 is hidden in the comb teeth of the rack 4, and the lower half of the middle part 1-2 and the upper half of the lower part 1-3 are exposed outside the comb teeth of the rack 4, that is, the connection between the middle part 1-2 and the lower part 1-3 of the pin 1 is exposed outside the comb teeth of the rack 4 in the horizontal direction and is not restricted in its flexible and free movement, when the lower part 1-3 of the pin 1 is subjected to a horizontal external force in a subsequent process, its stress will be concentrated at the intersection of the middle part 1-2 of the pin 1 and the lower surface of the comb teeth of the rack 4. The connection between the middle part 1-2 and the lower part 1-3 of the pin 1 and the lower part 1-3 of the pin 1 are all free and can move freely. The reaction force of the comb teeth of the rack 4 will not cause the lower part 1-3 of the pin 1 to deform, thereby ensuring the span between the two-sided pins 1 of the LCD. In a preferred embodiment of the present invention, the thickness of the comb teeth of the rack 4 is d It was thinned from the original 3.0mm to 1.5mm.

[0028] Step 3. Place the LCD screen 3 in front of the rack 4, with the openings of the upper parts 1-1 of all the pins 1 hanging on the rack 4 facing the edge steps of the LCD screen 3; set the push block 5 of the LCD pin mounting machine behind the rack 4, with the lower surface of the rear half of the push block 5 in contact with the upper surface of the rack 4, and there is a gap between the lower surface of the front half of the push block 5 and the upper surface of the rack 4, and the front end face of the push block 5 in contact with the upper middle part of the back side of the upper part 1-1 of the pin 1; under the horizontal forward thrust of the push block 5, the openings of the upper parts 1-1 of the pins 1 of all the pins 1 hanging on the rack 4 are embedded in the edge steps of the LCD screen 3, so that the pins 1 are installed on the edge steps of the LCD screen 3.

[0029] The entire lower surface (the lower surface of the rear half and the lower surface of the front half) of the push block 5 of the existing LCD pin mounting equipment is in contact with the upper surface of the rack 4, so that the front end of the push block 5 is in contact with the entire back surface (the upper, middle and lower parts of the back surface) of the upper portion 1-1 of the pin 1; Figure 3 As shown in (a), when push block 5 applies a horizontal forward thrust to pin 1, stress is concentrated at the intersection of pin 1 and the upper surface of the comb teeth of rack 4, that is, at the junction of upper portion 1-1 and middle portion 1-2 of pin 1. Since there is no gap between the lower end of the front end of push block 5 and the upper surface of the comb teeth of rack 4, the flexible and free movement of the junction between upper portion 1-1 and middle portion 1-2 of pin 1 is restricted. As a result, lower portion 1-3 of pin 1 is deformed, making it impossible to ensure the span between pins 1 on both sides of the LCD.

[0030] There is a gap between the rear half of the push block 5 of the existing LCD pin mounting machine and the upper surface of the rack 4, so that the front end of the push block 5 is in contact with the upper middle part of the upper part 1-1 of the pin 1; Figure 3As shown in (b). When the push block 5 applies a horizontal forward thrust to the pin 1, its stress will be concentrated at the intersection of the pin 1 and the upper surface of the comb teeth of the rack 4, that is, the connection between the upper part 1-1 and the middle part 1-2 of the pin 1, and there is a gap between the lower end of the front end face of the push block 5 and the upper surface of the comb teeth of the rack 4. The connection between the upper part 1-1 and the middle part 1-2 of the pin 1 is not restricted in its flexible and free movement. At the same time, the connection between the middle part 1-2 and the lower part 1-3 of the pin 1 and the lower part 1-3 of the pin 1 are all free and can move freely. Therefore, the lower part 1-3 of the pin 1 will not be deformed, thereby ensuring the span between the bilateral pins 1 of the LCD. In a preferred embodiment of the present invention, the gap between the lower surface of the front half of the push block 5 and the upper surface of the rack 4 is e 0.2mm.

[0031] Step 4: The pin cutting machine of the LCD pin mounting equipment cuts off the connecting strip 2 at the lower end of the pin 1 installed on the step at the edge of the LCD screen 3, so that each pin 1 can be separated and connected and conductive independently.

[0032] Step 5: Repeat the operations of steps 2-4 above to install pins 1 on both sides of the steps of the LCD screen 3 to obtain a prefabricated LCD.

[0033] Step 6: Fix the prefabricated LCD in the prepared LCD electrical test frame; Figure 4 As shown. The fixture 6-1 of the electrical test frame is set between the bilateral pins 1 of the prefabricated LCD and is in contact with the inner surface of the bilateral pins 1 of the prefabricated LCD. The upper surface of the fixture 6-1 is lower than the level of the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1. The two conductive adhesives 6-2 of the electrical test frame are respectively set on the outer sides of the bilateral pins 1 of the prefabricated LCD and are in contact with the outer surface of the bilateral pins 1 of the prefabricated LCD. The upper surfaces of the two conductive adhesives 6-2 are lower than the level of the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1. The electrical test frame is used to test the performance of the connection between the liquid crystal screen 3 and the pins 1. If the test passes, the prepared LCD is obtained.

[0034] The height of the upper surface of the fixture 6-1 is lower than the height of the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1. The height of the upper surfaces of the two conductive adhesives 6-2 is lower than the height of the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1, so that the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1 is completely free from air. This can prevent the external force that impacts the lower portion 1-3 of the pin 1 during the inspection process from causing the pin 1 to deform, thereby ensuring the span between the two-sided pins 1 of the LCD. In a preferred embodiment of the present invention, the height difference between the height of the upper surface of the fixture 6-1 and the height of the connection between the middle portion 1-2 and the lower portion 1-3 of the pin 1 is fThe height difference between the upper surface of the two conductive adhesives 6-2 and the connecting point of the middle part 1-2 and the lower part 1-3 of the corresponding pin 1 is 0.5mm. g Both are 1.0mm.

[0035] It should be noted that the rack 4, mounting machine, cutting machine and electric measuring frame of the LCD mounting equipment mentioned in the present invention are all original components of the existing LCD mounting equipment. Except for the structures of the rack 4 and the push block 5 of the mounting machine mentioned above, and the adjustment of the fixed position of the electric measuring frame, the other structures and working processes of each component follow the structures and working processes of the corresponding components in the existing LCD mounting equipment. Although the above embodiments of the present invention are illustrative, they are not limitations of the present invention. Therefore, the present invention is not limited to the above specific embodiments. Without departing from the principles of the present invention, any other embodiments obtained by those skilled in the art under the guidance of the present invention are deemed to be within the protection of the present invention.

Claims

1. A method for improving the span tolerance of LCD bilateral pins, characterized by: The steps are as follows: Step 1: Prepare a reel of pin (1) tray. The pin (1) tray consists of multiple F-shaped pins (1) and connecting bars (2) that connect these pins (1) together; each pin (1) consists of three parts, namely an upper part (1-1) in a C-shaped form, a middle part (1-2) in an inclined shape, and a lower part (1-3) in a vertical shape; the upper end of the middle part (1-2) is connected to the lower end of the upper part (1-1), and the lower end of the middle part (1-2) is connected to the upper end of the lower part (1-3). Step 2: Hang each pin (1) on the pin tray on the respective teeth of the rack (4) of the LCD pin mounting device in sequence, and the opening directions of the upper parts (1-1) of all the pins (1) are the same as the opening directions of the teeth of the rack (4); the thickness of the teeth of the rack (4) is less than the height of the middle part (1-2) of the pin (1), the lower edge of the upper part (1-1) of the pin (1) is in contact with the upper surface of the teeth of the rack (4), the middle part (1-2) of the pin (1) is embedded in the teeth of the rack (4), and the horizontal height of the lower end of the middle part (1-2) of the pin (1) is lower than the horizontal height of the lower surface of the teeth of the rack (4). Step 3: Place the liquid crystal display screen (3) in front of the rack (4). The opening directions of the upper parts (1-1) of all the pins (1) hanging on the rack (4) are directed at the edge steps of the liquid crystal display screen (3); set the pusher block (5) of the pin mounting machine of the LCD pin mounting device behind the rack (4). The lower surface of the rear half of the pusher block (5) is in contact with the upper surface of the rack (4), there is a gap between the lower surface of the front half of the pusher block (5) and the upper surface of the rack (4), and the front end face of the pusher block (5) is in contact with the upper middle part of the back surface of the upper part (1-1) of the pin (1); under the horizontal forward thrust of the pusher block (5), the openings of the upper parts (1-1) of all the pins (1) hanging on the rack (4) are embedded in the edge steps of the liquid crystal display screen (3) to install the pins (1) on the steps at the edge of the liquid crystal display screen (3). Step 4: The cutting machine of the LCD pin mounting device cuts off the connecting bar (2) at the lower end of the pin (1) installed on the steps at the edge of the liquid crystal display screen (3) so that each pin (1) can be separated to be independently connected and conduct electricity. Step 5: Repeat the operations in the above steps 2-4 to install pins (1) on both-sided steps of the liquid crystal display screen (3) to obtain a prefabricated LCD. Step 6, fixing the prefabricated LCD in the prepared electrical test frame of the LCD; setting the fixture (6-1) of the electrical test frame between the bilateral pins (1) of the prefabricated LCD and abutting the inner surface of the bilateral pins (1) of the prefabricated LCD, and the level of the upper surface of the fixture (6-1) is lower than the level of the connection between the middle part (1-2) and the lower part (1-3) of the pin (1); setting the two conductive adhesives (6-2) of the electrical test frame on the outer side of the bilateral pins (1) of the prefabricated LCD and abutting the outer surface of the bilateral pins (1) of the prefabricated LCD, and the level of the upper surface of the two conductive adhesives (6-2) is lower than the level of the connection between the middle part (1-2) and the lower part (1-3) of the pin (1); using the electrical test frame to detect the performance of the connection between the liquid crystal screen (3) and the pins (1), and obtaining the prepared LCD after the test passes.

2. The method for improving the span tolerance of LCD bilateral pins according to claim 1, wherein: In step 2, the thickness of the teeth of the rack (4) is reduced from 3.0 mm to 1.5 mm.

3. The method for improving the span tolerance of LCD bilateral pins according to claim 1, wherein: In step 3, the gap between the lower surface of the front half of the push block (5) and the upper surface of the rack (4) is 0.2 mm.

4. The method for improving the span tolerance of LCD bilateral pins according to claim 1, wherein: In step 6, the height difference between the horizontal height of the upper surface of the clamp (6-1) and the horizontal height of the connection point between the middle part (1-2) and the lower part (1-3) of the pin (1) is 0.5 mm, and the height difference between the horizontal height of the upper surface of the two conductive adhesives (6-2) and the horizontal height of the connection point between the middle part (1-2) and the lower part (1-3) of their corresponding pins (1) is 1.0 mm.

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