A method of replacing a false positive FPC

Abstract

The application discloses a method for replacing a dummy FPC, comprising the following steps: step 100, binding a dummy FPC to be replaced with a touch screen; step 200, placing the bound touch screen and dummy FPC in a dummy fixture; step 300, fixing the dummy FPC to the dummy fixture; step 400, peeling the dummy FPC from the touch screen; and step 500, removing the touch screen from the dummy fixture. The method has small position deviation between the replaced dummy FPC and the touch screen to be tested, and has high replacement efficiency.

Description

Technical Field

[0001] This invention relates to touch screen technology, and more particularly to a method for replacing a dummy pressure FPC. Background Technology

[0002] After the touch screen is manufactured, it needs to be bonded to the FPC with an anisotropic conductive film (ACF adhesive) to form an electrical connection. The FPC is equipped with a driver IC. The FPC is used to connect the touch screen to the motherboard with the processor so that the control signal obtained from the processor can be converted into a driving signal that can be recognized by the touch screen and drive the touch screen.

[0003] The touchscreen may be defective during manufacturing. If the touchscreen is bonded to the FPC without testing, the defective touchscreen may lead to waste of materials such as the FPC and driver IC. Therefore, the touchscreen needs to undergo a dummy pressure test before being bonded to the FPC.

[0004] The dummy pressure test refers to the process where, before the touchscreen is bonded, it is aligned and pressed with a dummy pressure FPC in a dummy pressure fixture, so that the dummy pressure gold fingers on the dummy pressure FPC form an electrical connection with the corresponding bonding gold fingers on the touchscreen. This simulates the environment in which the touchscreen is bonded to the FPC. Then, the dummy pressure FPC sends a test signal to the touchscreen to test whether the various functions of the touchscreen are normal.

[0005] During the sham pressure test, the sham pressure FPC on the sham pressure fixture is reused. After multiple sham pressure tests, the sham pressure gold fingers on the sham pressure FPC will wear out or become missing. Therefore, the sham pressure FPC on the sham pressure fixture needs to be replaced periodically.

[0006] In existing technology, when replacing the dummy pressure FPC, a CCD is generally used to first align the dummy pressure FPC with the dummy pressure fixture, and then fix the dummy pressure FPC on the dummy pressure fixture. This method of replacing the dummy pressure FPC makes it easy for there to be a large positional deviation between the dummy pressure FPC and the touch screen, requiring multiple calibrations, thus resulting in low replacement efficiency. Summary of the Invention

[0007] To address the shortcomings of the prior art, this invention provides a method for replacing a dummy pressure FPC, wherein the positional deviation between the replaced dummy pressure FPC and the touch screen is small, and the replacement efficiency is high.

[0008] The technical problem to be solved by the present invention is achieved through the following technical solution: A method for replacing a dummy FPC includes the following steps: Step 100: Bind the dummy FPC to be replaced to the touch screen; Step 200: Place the bound touchscreen and the dummy pressure FPC together inside the dummy pressure fixture; Step 300: Fix the dummy pressure FPC to the dummy pressure fixture; Step 400: Peel the dummy FPC from the touchscreen; Step 500: Remove the touchscreen from the dummy pressure fixture.

[0009] Furthermore, in step 100, when binding the dummy pressure FPC to be replaced to the touchscreen, the dummy pressure FPC is first aligned with the touchscreen under CCD monitoring, so that each dummy pressure gold finger on the dummy pressure FPC corresponds one-to-one with each binding gold finger on the touchscreen. Then, the dummy pressure gold fingers of the dummy pressure FPC are pasted and pressed to the binding gold fingers of the touchscreen using anisotropic conductive adhesive film, so that each dummy pressure gold finger and each binding gold finger form a one-to-one electrical connection through the anisotropic conductive adhesive film. Then, the touch function of the touchscreen is tested through the dummy pressure FPC to determine whether the dummy pressure FPC and the touchscreen are successfully bound. If the binding is successful, step S200 is executed. If the binding is unsuccessful, the dummy pressure FPC is peeled off from the touchscreen and rebound until the binding is successful.

[0010] Furthermore, the dummy pressure fixture includes a screen limiting groove and an FPC supporting groove, wherein the FPC supporting groove is connected to one side of the screen limiting groove; the screen limiting groove is used to accommodate the touch screen and limit the relative position between the touch screen and the dummy pressure fixture, and the FPC supporting groove is used to accommodate and support the dummy pressure FPC.

[0011] Furthermore, when the touch screen is placed in the screen limiting groove of the dummy pressure fixture, the four side walls of the screen limiting groove abut against the four side edges of the touch screen.

[0012] Furthermore, the depth of the FPC support groove is greater than the depth of the screen limiting groove.

[0013] Furthermore, the depth difference between the FPC support groove and the screen limiting groove is equal to the thickness of the dummy FPC.

[0014] Furthermore, the width of the FPC support groove is greater than the width of the dummy FPC.

[0015] Furthermore, the dummy pressure fixture also includes a clearance groove, which is located in the middle of the screen limiting groove. When the touch screen is placed in the screen limiting groove, the clearance groove corresponds to the circuit area on the surface of the touch screen.

[0016] Furthermore, the bottom periphery of the screen limiting groove protrudes from the avoidance groove to form a screen support portion, which supports the edge of the touch screen.

[0017] Furthermore, the screen limiting groove protrudes at least on the two oppositely arranged side walls to form the screen support portion.

[0018] The present invention has the following beneficial effects: The method first binds the dummy pressure FPC to the touch screen to fix the relative position between the dummy pressure FPC and the touch screen. Then, the bound touch screen and the dummy pressure FPC are placed together in the dummy pressure fixture. Since the dummy pressure fixture has a limiting effect on the touch screen, the relative position between the dummy pressure FPC bound to the touch screen and the dummy pressure fixture is also limited. Finally, the dummy pressure FPC is fixed on the dummy pressure fixture, and the touch screen is peeled off and removed, so as to achieve the purpose of transferring and replacing the dummy pressure FPC from the touch screen to the dummy pressure fixture. Since the touch screen to be tested and the touch screen used when replacing the dummy pressure FPC are products of the same size, specification, and model, the touch screen to be tested is also subject to the limiting effect in the dummy pressure fixture, and thus naturally aligns with the dummy pressure FPC. The positional deviation between the replaced dummy pressure FPC and the touch screen is small, no secondary calibration is required, and the replacement efficiency is high. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating the steps of the method for replacing a dummy FPC provided by the present invention.

[0020] Figure 2 This is a schematic diagram of the structure of the dummy pressure FPC, touch screen, and dummy pressure fixture before and after replacement according to the present invention.

[0021] Figure 3 This is a front view of the dummy pressure fixture of the present invention.

[0022] Figure 4 This is a cross-sectional view of the dummy pressure FPC, touch screen, and dummy pressure fixture of the present invention after loading. Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and embodiments, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this invention, "multiple" means two or more, unless otherwise explicitly specified.

[0026] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," and "setting," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Example

[0027] like Figure 1 and 2 As shown, a method for replacing a dummy FPC200 includes the following steps: Step 100: Bind the dummy pressure FPC200 to be replaced to the touch screen 100; Step 200: Place the bound touchscreen 100 and the dummy pressure FPC 200 together inside the dummy pressure fixture 300; Step 300: Fix the dummy pressure FPC200 to the dummy pressure fixture 300; Step 400: Peel the dummy pressure FPC 200 from the touch screen 100; Step 500: Remove the touch screen 100 from the dummy pressure fixture 300.

[0028] This method involves first binding the dummy pressure FPC 200 to the touchscreen 100 to fix their relative positions. Then, the bound touchscreen 100 and dummy pressure FPC 200 are placed together inside the dummy pressure fixture 300. Because the dummy pressure fixture 300 limits the movement of the touchscreen 100, the relative position of the dummy pressure FPC 200 bound to the touchscreen 100 is also restricted. Finally, the dummy pressure FPC 200 is fixed to the dummy pressure fixture 300. The touch screen 100 is peeled off and removed to transfer the dummy pressure FPC 200 from the touch screen 100 to the dummy pressure fixture 300. Since the touch screen to be tested and the touch screen 100 used when replacing the dummy pressure FPC 200 are the same size, specification and model, the touch screen to be tested is also limited in the dummy pressure fixture 300, and thus naturally aligns with the dummy pressure FPC 200. The positional deviation between the replaced dummy pressure FPC 200 and the touch screen 100 is small, no secondary calibration is required, and the replacement efficiency is high.

[0029] In step 100, when binding the dummy pressure FPC 200 to be replaced to the touch screen 100, the dummy pressure FPC 200 and the touch screen 100 are first aligned under CCD monitoring, so that each dummy pressure gold finger on the dummy pressure FPC 200 corresponds one-to-one with each binding gold finger on the touch screen 100. Then, each dummy pressure gold finger of the dummy pressure FPC 200 and each binding gold finger of the touch screen 100 are pasted and pressed together and fixed using anisotropic conductive adhesive film (ACF adhesive), so that each dummy pressure gold finger and each binding gold finger form a one-to-one electrical connection through the gold balls in the anisotropic conductive adhesive film. Then, the touch function of the touch screen 100 is tested through the dummy pressure FPC 200 to determine whether the dummy pressure FPC 200 and the touch screen 100 are successfully bound. If the binding is successful, step S200 is executed. If the binding is unsuccessful, the dummy pressure FPC 200 is peeled off from the touch screen 100 and rebound until the binding is successful.

[0030] like Figure 3 and 4 As shown, the dummy pressure fixture 300 includes a screen limiting groove 310 and an FPC support groove 320. The FPC support groove 320 is connected to one side of the screen limiting groove 310. The screen limiting groove 310 is used to accommodate the touch screen 100 and limit the relative position between the touch screen 100 and the dummy pressure fixture 300. The FPC support groove 320 is used to accommodate and support the dummy pressure FPC 200.

[0031] In step 200, after the bound touch screen 100 and the dummy pressure FPC 200 are placed together in the dummy pressure fixture 300, the touch screen 100 is placed in the screen limiting groove 310 of the dummy pressure fixture 300 and its relative position with the dummy pressure fixture 300 is restricted by the screen limiting groove 310. The dummy pressure FPC 200 is placed in the FPC support groove 320 of the dummy pressure fixture 300 and is supported by the FPC support groove 320.

[0032] The length and width dimensions of the screen limiting groove 310 are the same as or have a tolerance gap with the length and width dimensions of the touch screen 100. When the touch screen 100 is placed in the screen limiting groove 310 of the dummy pressure fixture 300, the four side walls of the screen limiting groove 310 abut against the four side edges of the touch screen 100, thereby restricting the touch screen 100 within the screen limiting groove 310.

[0033] The depth of the FPC support groove 320 can be greater than the depth of the screen limiting groove 310. The touch screen 100 placed in the screen limiting groove 310 has one side of the dummy pressure FPC 200 facing the bottom of the screen limiting groove 310. The dummy pressure FPC 200 is placed in the FPC support groove 320 with a greater depth to prevent the touch screen 100 located in the screen limiting groove 310 from being lifted and tilted by the dummy pressure FPC 200.

[0034] When picking up or placing the touch screen 100, the tester's fingers can grasp the side of the touch screen 100 from the FPC support groove 320. Therefore, the depth of the screen limiting groove 310 can be less than the thickness of the touch screen 100.

[0035] Preferably, the depth difference between the FPC support groove 320 and the screen limiting groove 310 is equal to the thickness of the dummy pressure FPC 200.

[0036] The width of the FPC support groove 320 is greater than the width of the dummy pressure FPC 200, so as to facilitate the entry and exit of the tester's fingers when picking up and placing the touch screen 100. Therefore, the depth of the screen limiting groove 310 can also be equal to the thickness of the touch screen 100.

[0037] Meanwhile, sufficient width is reserved for the FPC support groove 320 so that the dummy pressure fixture 300 can be used to perform dummy pressure tests on touch screens 100 of the same size but with different binding positions. The dummy pressure FPC 200 can be fixed at different positions along the width direction of the FPC support groove 320 according to its different binding positions on the touch screen 100.

[0038] For some touch screens 100 of the same size, the final bonding position (i.e. the bonding position of the gold fingers) will be different due to wiring reasons. For example, the FPC is generally bonded in the center of the side of the touch screen 100, but due to wiring reasons, the FPC is sometimes bonded in a non-centered position on the side of the touch screen 100. By reserving a sufficiently wide FPC support groove 320, the dummy pressure FPC 200 can be fixed at different positions along the width direction of the FPC support groove 320 according to the bonding position on the touch screen 100, thereby improving the utilization rate of the dummy pressure fixture 300.

[0039] The dummy pressure fixture 300 also includes a clearance groove 330, which is located in the middle of the screen limiting groove 310. When the touch screen 100 is placed in the screen limiting groove 310, the clearance groove 330 corresponds to the circuit area on the surface of the touch screen 100.

[0040] This patent allows for the creation of a clearance groove 330 at the bottom center of the screen limiting groove 310. When the touchscreen 100 is placed within the screen limiting groove 310, the side surface of the touchscreen 100 with circuitry faces the bottom of the screen limiting groove 310. The outer periphery of the bottom surface of the screen limiting groove 310 protrudes from the clearance groove 330 to form a screen support portion 311. The screen support portion 311 supports the edge of the touchscreen 100. The clearance groove 330 can avoid the circuitry area on the surface of the touchscreen 100, thus preventing damage to the circuitry on the surface of the touchscreen 100 due to contact and friction with the dummy pressure fixture 300.

[0041] The screen limiting groove 310 includes a first sidewall, a second sidewall, a third sidewall, and a fourth sidewall connected in sequence, wherein the first sidewall is disposed opposite to the third sidewall, and the second sidewall is disposed opposite to the fourth sidewall; the screen limiting groove 310 has a screen support portion 311 protruding on at least the first sidewall and the third sidewall that abuts against the edge of the touch screen 100, or at least on the second sidewall and the fourth sidewall that has a screen support portion 311 protruding on at least the second sidewall and the fourth sidewall that abuts against the edge of the touch screen 100.

[0042] In this embodiment, screen support portions 311 are protruding on the first, second, third, and fourth sidewalls of the screen limiting groove 310, wherein the length of the screen support portion 311 on the first sidewall on the same side as the FPC support groove 320 is the same as the length of the touch screen 100.

[0043] In step 300, an adhesive can be used to bond and fix the dummy pressure FPC200 to the dummy pressure fixture 300, or other mechanical structures such as buckles or pressure strips can be used to bond and fix the dummy pressure FPC200 to the dummy pressure fixture 300.

[0044] Preferably, a variable viscosity adhesive can be used to bond and fix the dummy pressure FPC200 to the dummy pressure fixture 300. The variable viscosity adhesive refers to a type of adhesive with high viscosity under normal conditions and low viscosity under special conditions. For example, thermosensitive adhesives exhibit high viscosity at room temperature and low viscosity at high temperatures, and UV adhesives exhibit high viscosity under non-UV light conditions and low viscosity under UV light conditions. By using the variable viscosity adhesive to bond the dummy pressure FPC200 to the dummy pressure fixture 300, when replacing the dummy pressure FPC200, the viscosity of the variable viscosity adhesive can be reduced under special conditions before the old FPC is peeled off from the dummy pressure fixture 300 without affecting the dummy pressure test under normal conditions.

[0045] In step 400, since the dummy pressure FPC200 and the touch screen 100 are bonded and fixed only by the anisotropic conductive adhesive film (ACF adhesive) during the bonding process, and the anisotropic conductive adhesive film is a pressure-sensitive adhesive, the adhesive force of which is related to the magnitude of the pressure force it receives during bonding. Therefore, in step 100, an appropriate pressure force can be used when bonding the dummy pressure FPC200 and the touch screen 100, so that the adhesive force of the anisotropic conductive adhesive film can both maintain the bonding between the dummy pressure FPC200 and the touch screen 100 and also facilitate direct manual peeling.

[0046] Of course, laser peeling or other methods can also be used to assist in peeling the dummy FPC200 from the touch screen 100.

[0047] After removing the touchscreen 100 from the dummy pressure fixture 300, the touchscreen to be tested is directly placed into the screen limiting groove 310 of the dummy pressure fixture 300. The bonding gold fingers on the touchscreen to be tested will be directly aligned with the dummy pressure gold fingers on the dummy pressure FPC 200. Then, only pressure needs to be applied to the touchscreen to be tested to press the bonding gold fingers on the touchscreen to be tested into contact with the dummy pressure gold fingers on the dummy pressure FPC 200 to form an electrical connection. The touch function of the touchscreen to be tested can then be tested through the dummy pressure FPC 200.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention and not to limit them. Although the embodiments of the present invention have been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the embodiments of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for replacing a dummy pressure FPC, characterized in that, Includes the following steps: Step 100: Bond the new dummy FPC to the touchscreen; Step 200: Place the bound touchscreen and the dummy pressure FPC together inside the dummy pressure fixture; Step 300: Fix the dummy pressure FPC to the dummy pressure fixture; Step 400: Peel the dummy FPC from the touchscreen; Step 500: Remove the touchscreen from the dummy pressure fixture; The touchscreen under test and the touchscreen used when replacing the dummy FPC are products of the same size, specifications and model.

2. The method for replacing the dummy pressure FPC according to claim 1, characterized in that, In step 100, when bonding the new dummy FPC to the touchscreen, the dummy FPC is first aligned with the touchscreen under CCD monitoring, so that each dummy gold finger on the dummy FPC corresponds one-to-one with each bonding gold finger on the touchscreen. Then, an anisotropic conductive adhesive film is used to stick and press the dummy gold fingers of the dummy FPC to the bonding gold fingers of the touchscreen, so that each dummy gold finger and each bonding gold finger forms a one-to-one electrical connection through the anisotropic conductive adhesive film. Then, the touch function of the touchscreen is tested through the dummy FPC to determine whether the bonding between the dummy FPC and the touchscreen is successful. If the bonding is successful, step S200 is executed. If the bonding is unsuccessful, the dummy FPC is peeled off from the touchscreen and rebonded until the bonding is successful.

3. The method for replacing the dummy pressure FPC according to claim 1, characterized in that, The dummy pressure fixture includes a screen limiting groove and an FPC supporting groove. The FPC supporting groove is connected to one side of the screen limiting groove. The screen limiting groove is used to accommodate the touch screen and limit the relative position between the touch screen and the dummy pressure fixture. The FPC supporting groove is used to accommodate and support the dummy pressure FPC.

4. The method for replacing the dummy pressure FPC according to claim 3, characterized in that, When the touch screen is placed in the screen limiting groove of the dummy pressure fixture, the four side walls of the screen limiting groove abut against the four side edges of the touch screen.

5. The method for replacing the dummy pressure FPC according to claim 3, characterized in that, The depth of the FPC support groove is greater than the depth of the screen limiting groove.

6. The method for replacing the dummy pressure FPC according to claim 5, characterized in that, The depth difference between the FPC support groove and the screen limiting groove is equal to the thickness of the dummy FPC.

7. The method for replacing the dummy pressure FPC according to claim 3, characterized in that, The width of the FPC support groove is greater than the width of the dummy FPC.

8. The method for replacing the dummy pressure FPC according to claim 3, characterized in that, The dummy pressure fixture also includes a clearance groove, which is located in the middle of the screen limiting groove. When the touch screen is placed in the screen limiting groove, the clearance groove corresponds to the circuit area on the surface of the touch screen.

9. The method for replacing the dummy pressure FPC according to claim 8, characterized in that, The bottom periphery of the screen limiting groove protrudes from the avoidance groove to form a screen support portion, which supports the edge of the touch screen.

10. The method for replacing the dummy pressure FPC according to claim 9, characterized in that, The screen limiting groove protrudes at least on the two oppositely arranged side walls to form the screen support portion.

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