A highly weather-resistant SMD LED light-emitting tube and its packaging process

Abstract

The present invention discloses a highly weather-resistant SMD LED light-emitting tube, comprising a shell structure and an electrode support constituting the electrode lead end of the LED light-emitting tube chip, wherein a first cavity and a second cavity that are mutually interpenetrating are formed inside the shell structure; the electrode support is fixedly arranged on the inner wall of the first cavity, and the electrode support comprises a middle part and end heads on both sides, wherein the middle part is fixed on the inner wall of the first cavity, and at least one end head on one side of the end heads on both sides extends along the inner wall of the first cavity toward the outer wall, and is abutted against the outer wall of the shell structure corresponding to the first cavity. The technical solution of the present invention aims to enhance the weather resistance of the light-emitting tube and reduce the impact of the light-emitting tube on the harsh environment.

Description

Technical Field

[0001] The invention relates to the technical field of light-emitting tubes, and in particular to a highly weather-resistant SMD LED light-emitting tube and a packaging process thereof. Background Art

[0002] LED outdoor display screens made of LED light-emitting tubes using SMD packaging technology have become the mainstream product for outdoor displays. As outdoor display screens are exposed to sunlight for a long time, high and low temperature differences, wind and rain erosion, harmful gases and other harsh environments, the weather resistance of the LED light-emitting tube devices of the display screen will directly affect the display quality and life of the display screen.

[0003] LED light-emitting tubes used in outdoor display screens generally adopt a normal LED chip package in a bracket in the industry. The electrode lead of the LED chip is welded to the electrode bracket of the chip in a long wire with a certain arc. Due to the small space inside the LED light-emitting tube, the welding point at the other end of the electrode wire is close to the side of the electrode inside the light-emitting tube. When the LED light-emitting tube is subjected to the impact of harsh environment during use, causing the shell to expand and contract, the welding point on the side of the electrode is subjected to the greatest expansion and contraction stress deformation, which can easily cause the welding wire at this location to detach or be damaged; at the same time, wind, rain and harmful gases will gradually penetrate into the chip and chip electrode lead welding points near the side of the light-emitting tube for a long time, rust the welding points, resulting in reduced electrode line connection performance, thereby causing a serious decline in the quality of the display screen.

[0004] In addition, because traditional LED light-emitting tubes have built-in red, green and blue chips, the positive and negative poles of each chip correspond to the electrode welding feet of an electrode bracket, and the total number of electrode welding feet is at most 6. The welding thrust value with the external PCB board is insufficient. After using for a period of time, if it is impacted by the outside world, the LED light-emitting tube is easy to separate from the external PCB board. Summary of the invention

[0005] The first object of the present invention is to provide a highly weather-resistant SMD LED light-emitting tube, aiming to enhance the weather resistance of the SMD LED light-emitting tube, reduce the influence of the light-emitting tube on the harsh environment, and improve the quality of the SMD LED light-emitting tube.

[0006] To achieve the above object, the present invention provides a highly weather-resistant SMD LED light-emitting tube, comprising:

[0007] A shell structure, wherein a first cavity and a second cavity that are interconnected are formed inside the shell structure;

[0008] An electrode bracket constituting the electrode lead end of the LED light-emitting tube chip is fixedly arranged on the inner wall of the first cavity. The electrode bracket includes a middle part and end heads on both sides. The middle part is fixed on the inner wall of the first cavity, and at least one end head on both sides extends along the inner wall of the first cavity to the outer wall, and is placed in contact with the outer wall of the shell structure corresponding to the first cavity.

[0009] By adopting the above technical solution, since the electrode sheet is made of metal material, its resistance to thermal expansion and contraction is stronger than that of the plastic shell, thereby improving the ability of the entire SMD LED light-emitting tube shell to resist the impact of harsh environments.

[0010] Preferably, the cross-sections of the first cavity and the second cavity are both trapezoidal, and the cross-sectional area of ​​the second cavity is larger than the cross-sectional area of ​​the first cavity.

[0011] By adopting the above technical solution, the path for gas or water vapor to enter the first cavity can be lengthened, while the light radiation range of the LED light-emitting chip is not affected.

[0012] Preferably, the electrode bracket includes a first electrode bracket, a second electrode bracket, a third electrode bracket, a fourth electrode bracket, and a fifth electrode bracket;

[0013] The end portions on both sides of the first electrode bracket extend along the inner wall of the first cavity toward the outer wall, and are abutted against the outer wall of the shell structure corresponding to the first cavity;

[0014] The second electrode bracket, the third electrode bracket, and the fourth electrode bracket all have an end portion on one side extending along the inner wall of the first cavity toward the outer wall, and are placed in contact with the outer wall of the shell structure corresponding to the first cavity;

[0015] The end portions on both sides of the fifth electrode bracket extend along the inner wall of the first cavity toward the outer wall, and are abutted against the outer wall of the shell structure corresponding to the first cavity;

[0016] The positive and negative electrodes of the red LED flip chip are respectively fixedly connected to the first electrode bracket and the second electrode bracket;

[0017] The positive and negative electrodes of the green LED flip chip are respectively fixedly connected to the third electrode bracket and the first electrode bracket;

[0018] The positive and negative electrodes of the blue LED flip chip are fixedly connected to the fifth electrode bracket and the fourth electrode bracket respectively.

[0019] By adopting the above technical solution, the structure of the present invention can make the red / green / blue LED flip chips be located at a relatively central position at the bottom of the first cavity. When the external high and low temperature changes or physical impacts cause the shell structure to deform, the flip chips located at the central position of the bottom of the inner wall of the first cavity are subjected to the least stress deformation, thereby achieving the strongest resistance to physical environmental impact.

[0020] The increased number of electrode sheets increases the soldering area between the LED light-emitting tube and the externally connected PCB board, increases the number of soldering points, improves the soldering strength, and greatly increases the soldering thrust value of the LED light-emitting tube.

[0021] Preferably, a side wall extension portion for extending the path length of gas entering the first cavity is provided on the side wall of the shell structure corresponding to the first cavity, and the shape of the electrode bracket at the side wall extension portion is the same as the shape of the side wall extension portion.

[0022] By adopting the above technical solution, the arrangement of the electrode bracket and the shell structure can lengthen the path for gas or water vapor to enter the first cavity, improve the airtightness of the LED light-emitting tube, and thus enhance its anti-corrosion ability.

[0023] Preferably, the first cavity is filled with a first packaging glue, the electrode bracket is located at the connecting portion between the inner wall and the outer wall, and at the transition portion between the first cavity and the second cavity, and the surface formed after the first packaging glue is cured covers the connecting portion between the inner wall and the outer wall of the electrode bracket;

[0024] The second plastic shell is filled with second packaging glue.

[0025] By adopting the above technical solution, the solidified connection parts of the first packaging glue and the second packaging glue with the electrode support and the shell structure are enlarged, thereby enhancing the tensile strength of the connection between the electrode support and the shell structure.

[0026] The second object of the present invention is to provide a packaging process for a highly weather-resistant SMD LED light-emitting tube, so as to manufacture a highly weather-resistant LED light-emitting tube in a simple, convenient and low-cost manner.

[0027] A packaging process for a highly weather-resistant SMD LED light-emitting tube, used for preparing any of the above-mentioned highly weather-resistant SMD LED light-emitting tubes, comprising:

[0028] S10, setting a bracket mold for punching the electrode bracket, wherein the shape of the cavity of the bracket mold is the same as the shape of the electrode bracket to be formed;

[0029] A plastic mold for injection molding the shell structure is provided, wherein the shape of the cavity of the plastic mold is the same as the shape of the shell structure to be molded;

[0030] S20, using a punching machine in conjunction with a bracket mold to punch a copper sheet or an iron sheet into an electrode bracket, and then silver-plating the surface of the electrode bracket;

[0031] S30, placing the electrode bracket in a plastic mold, and using an injection molding machine to injection mold a shell structure with the electrode bracket;

[0032] S40, using a die bonding machine to fix the red LED flip chip, the green LED flip chip, and the blue LED flip chip on the corresponding electrode brackets;

[0033] S50, dripping a first packaging glue into the first cavity using a glue dispenser, and then dripping a second packaging glue into the second cavity after the first packaging glue is initially cured, and curing the second packaging glue.

[0034] Preferably, the surface of the electrode sheet is coated with conductive solder, and the red LED flip chip, the green LED flip chip and the blue LED flip chip are fixedly connected to the electrode sheet via the conductive solder.

[0035] By adopting the above technical solutions, the bracket mold can realize stable and reliable mass production of electrode brackets; the plastic mold can realize stable and reliable mass production of shell structures; the whole packaging process is simple, convenient and low-cost, and the manufactured LED light-emitting tube has strong weather resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 This is a structural schematic diagram of an embodiment of a highly weather-resistant SMD LED light-emitting tube of the present invention;

[0038] Figure 2 It is a structural schematic diagram of another viewing angle of an embodiment of a highly weather-resistant SMD LED light-emitting tube of the present invention;

[0039] Figure 3 for Figure 2 Section view at AA;

[0040] Figure 4 for Figure 2 Sectional view at BB;

[0041] Figure 5This is a schematic structural diagram from another viewing angle of an embodiment of a highly weather-resistant SMD LED light-emitting tube of the present invention.

[0042] Description of Figure Numbers:

[0043] 10. Shell structure; 11. First cavity; 111. Extension portion; 12. Second cavity; 20. Electrode bracket; 21. First electrode bracket; 22. Second electrode bracket; 23. Third electrode bracket; 24. Fourth electrode bracket; 25. Fifth electrode bracket; 26. Red LED flip chip; 27. Green LED flip chip; 28. Blue LED flip chip.

[0044] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0046] For the problems in the background technology, refer to Figures 1 to 5 As shown, the present invention proposes a highly weather-resistant SMD LED light-emitting tube, including a shell structure 10 and an electrode holder 20 constituting an electrode lead end of an LED light-emitting tube chip, wherein a first cavity 11 and a second cavity 12 which are interconnected are formed inside the shell structure 10; the electrode holder 20 is fixedly arranged on the inner wall of the first cavity 11, and the electrode holder 20 includes a middle part and end heads on both sides, wherein the middle part is fixed on the inner wall of the first cavity 11, and at least one end head on one side of the end heads on both sides extends along the inner wall of the first cavity 11 to the outer wall, and is abutted against the outer wall of the shell structure 10 corresponding to the first cavity 11.

[0047] The shell structure 10 can be formed by plastic injection molding, and a first cavity 11 and a second cavity 12 that are interconnected are formed therein. The first cavity 11 can be a cup-shaped structure with a groove, and the shape of its longitudinal section can be trapezoidal, rectangular, hemispherical or other shapes. The second cavity 12 can be an inverted trapezoidal cup-shaped structure that passes through from top to bottom, that is, the upper opening area is larger than the bottom opening area. The first cavity 11 and the second cavity 12 can be integrally formed by injection molding.

[0048] An electrode bracket is provided at the bottom of the first cavity 11, the middle part of the electrode bracket is laid flat on the bottom of the first cavity 11, and the two ends are pin parts, which are respectively attached to the inner wall of the first cavity 11 and extend upward, and then bend outward at the edge of the first cavity 11, and then extend toward the bottom in accordance with the outer wall surface of the first cavity 11, and finally buckle at the bottom of the first cavity 11. After the second cavity 12 is solidified and connected to the first cavity 11, the electrode bracket can be injection molded at the connection between the first cavity 11 and the second cavity 12, so as to fix the metal sheet bracket. By adopting the above technical solution, since the electrode sheet is made of metal material, its resistance to thermal expansion and contraction is stronger than that of the plastic shell, thereby improving the ability of the plastic shell of the entire SMD LED light-emitting tube to resist the impact of harsh environments.

[0049] Combined with reference Figure 3 and Figure 4 As shown, in one embodiment of the present application, the cross-sections of the first cavity 11 and the second cavity 12 are both trapezoidal, and the cross-sectional area of ​​the second cavity 12 is larger than the cross-sectional area of ​​the first cavity 11. Setting the cross-sectional shape of the first cavity 11 and the second cavity 12 to a trapezoid can enhance the light reflection ability and improve the light effect. It can also increase the path for gas or water vapor to enter the first cavity 11, while not affecting the light radiation range of the LED light-emitting chip.

[0050] In one embodiment of the present application, the electrode bracket 20 includes a first electrode bracket 21, a second electrode bracket 22, a third electrode bracket 23, a fourth electrode bracket 24, and a fifth electrode bracket 25; the end portions on both sides of the first electrode bracket 21 extend along the inner wall of the first cavity 11 to the outer wall, and are abutted against the outer wall of the shell structure 10 corresponding to the first cavity 11; the second electrode bracket 22, the third electrode bracket 23, and the fourth electrode bracket 24 all have end portions on one side extending along the inner wall of the first cavity 11 to the outer wall, and are abutted against the shell structure 10. 0 is at the outer wall of the first cavity 11; the end portions on both sides of the fifth electrode bracket 25 extend toward the outer wall along the inner wall of the first cavity 11 respectively, and are abutted against the outer wall of the shell structure 10 corresponding to the first cavity 11; the positive and negative electrodes of the red LED flip chip 26 are fixedly connected to the first electrode bracket 21 and the second electrode bracket 22 respectively; the positive and negative electrodes of the green LED flip chip 27 are fixedly connected to the third electrode bracket 23 and the first electrode bracket 21 respectively; the positive and negative electrodes of the blue LED flip chip 28 are fixedly connected to the fifth electrode bracket 25 and the fourth electrode bracket 24 respectively.

[0051] In this embodiment, the LED flip chips of the three colors of red / green / blue can be located at a relatively central position at the bottom of the first cavity 11. When the external high and low temperature changes or physical impacts cause the shell structure to deform, the flip chips located at the central position of the bottom of the inner wall of the first cavity 11 are subjected to the least stress deformation, thereby achieving the strongest resistance to physical environmental impact; the setting of the increased number of electrode sheets increases the welding area and the number of welding points of the LED light-emitting tube and the externally connected PCB board, thereby improving the welding strength and greatly increasing the welding thrust value of the LED light-emitting tube.

[0052] Combined with reference Figure 3 As shown, in one embodiment of the present application, the side wall of the shell structure 10 corresponding to the first cavity 11 is provided with a side wall extension portion 111 for extending the path length of the gas entering the first cavity 11, and the shape of the electrode bracket at the side wall extension portion 111 is the same as the shape of the side wall extension portion 111. By adopting the above technical solution, the arrangement of the electrode bracket and the shell structure 10 can increase the path for gas or water vapor to enter the first cavity 11, improve the airtightness of the LED light-emitting tube, and thus enhance its anti-corrosion ability.

[0053] Exemplarily, a beveled portion can be provided on the circumference of the outer edge of the first cavity 11, and part of the electrode holder is attached to the beveled portion. When the electrode holder shrinks and deforms due to temperature changes, most of the stress of the electrode holder shrinking toward the inside of the first cavity 11 is distributed in a direction perpendicular to the beveled portion, thereby transferring the stress to the outer wall of the first cavity 11. The outer wall of the first cavity 11 is sufficient to resist the force of the electrode holder shrinking and deforming, thereby preventing the electrode holder from shrinking and deforming inward, causing the electrode holder LED light-emitting chip to fall off or crack after being subjected to deformation stress. As a result, the ability of the light-emitting tube to resist cold and heat shocks can be enhanced, and its strong weather resistance can be enhanced.

[0054] In one embodiment of the present application, the first cavity 11 is filled with a first packaging glue (not shown in the figure), the electrode holder is located at the connecting portion between the inner wall and the outer wall, and at the transition portion between the first cavity 11 and the second cavity 12, and the surface formed after the first packaging glue is cured covers the connecting portion between the inner wall and the outer wall of the electrode holder; the second plastic shell is filled with a second packaging glue (not shown in the figure).

[0055] The first packaging glue filled in the first cavity 11 is mainly used to seal the electrode support and the LED light-emitting chip on the electrode support, and forms a closed space with the outer wall of the first cavity 11; the second packaging glue filled in the second cavity 12 is used to prevent ultraviolet erosion and enhance the luminous performance. Ultraviolet rays and harmful gases need to pass through the second packaging glue and the first packaging glue to enter the LED light-emitting chip on the electrode support. The superimposed and increased penetration path will reduce the degree of damage to the LED package chip packaged on the electrode support by ultraviolet rays and harmful gases. At the same time, the length of the multi-section tortuous airtight path is much longer than the length from the side welding point of the flat-bottomed internal electrode lead of the general light-emitting tube to the outer wall surface, which has stronger airtightness and improved anti-corrosion ability. In addition, the cured connection parts of the first packaging glue and the second packaging glue with the electrode support and the shell structure 10 are enlarged, thereby enhancing the tensile strength of the connection between the electrode support and the shell structure 10.

[0056] The present invention also provides a packaging process for a highly weather-resistant SMD LED light-emitting tube, which is used to prepare a highly weather-resistant SMD LED light-emitting tube as described in any of the previous embodiments, comprising the following steps:

[0057] S10, setting a bracket mold for punching the electrode bracket, wherein the shape of the cavity of the bracket mold is the same as the shape of the electrode bracket to be formed;

[0058] A plastic mold for injection molding the shell structure is provided, wherein the shape of the cavity of the plastic mold is the same as the shape of the shell structure to be molded;

[0059] S20, using a punching machine in conjunction with a bracket mold to punch a copper sheet or an iron sheet into an electrode bracket, and then silver-plating the surface of the electrode bracket;

[0060] S30, placing the electrode bracket in a plastic mold, and using an injection molding machine to injection mold a shell structure with the electrode bracket;

[0061] S40, using a die bonding machine to fix the red LED flip chip, the green LED flip chip, and the blue LED flip chip on the corresponding electrode brackets;

[0062] S50, dripping a first packaging glue into the first cavity using a glue dispenser, and then dripping a second packaging glue into the second cavity after the first packaging glue is initially cured, and curing the second packaging glue.

[0063] Preferably, the surface of the electrode sheet is coated with solder, and the red LED flip chip, the green LED flip chip, and the blue LED flip chip are fixedly connected to the electrode sheet through the solder.

[0064] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of this application, it should be understood that if the terms "upper", "lower", "left", "right", etc. indicate an orientation or position relationship based on the orientation or position relationship shown in the drawings, it is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0065] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A highly weather-resistant SMD LED light-emitting tube, characterized in that: include: A shell structure, wherein a first cavity and a second cavity that are interconnected are formed inside the shell structure; An electrode bracket constituting the electrode lead end of the LED light-emitting tube chip, the electrode bracket is fixedly arranged on the inner wall of the first cavity, the electrode bracket includes a middle part and end heads on both sides, the middle part is fixed on the inner wall of the first cavity, the end heads on both sides are respectively bent outward at the edge of the inner wall of the first cavity and extend toward the bottom along the outer wall surface of the first cavity and buckled with the bottom of the first cavity, and the electrode bracket is injection molded at the connection between the first cavity and the second cavity; Wherein, the electrode bracket includes a first electrode bracket, a second electrode bracket, a third electrode bracket, a fourth electrode bracket, and a fifth electrode bracket; The end portions on both sides of the first electrode bracket extend along the inner wall of the first cavity toward the outer wall, and are abutted against the outer wall of the shell structure corresponding to the first cavity; The second electrode bracket, the third electrode bracket, and the fourth electrode bracket all have an end portion on one side extending along the inner wall of the first cavity toward the outer wall, and are placed in contact with the outer wall of the shell structure corresponding to the first cavity; The end portions on both sides of the fifth electrode bracket extend along the inner wall of the first cavity toward the outer wall, and are abutted against the outer wall of the shell structure corresponding to the first cavity; The positive and negative electrodes of the red LED flip chip are respectively fixedly connected to the first electrode bracket and the second electrode bracket; The positive and negative electrodes of the green LED flip chip are respectively fixedly connected to the third electrode bracket and the first electrode bracket; The positive and negative electrodes of the blue LED flip chip are fixedly connected to the fifth electrode bracket and the fourth electrode bracket respectively.

2. The highly weather-resistant SMD LED light-emitting tube according to claim 1, characterized in that: The cross-sections of the first cavity and the second cavity are both trapezoidal, and the cross-section area of ​​the second cavity is larger than the cross-section area of ​​the first cavity.

3. The highly weather-resistant SMD LED light-emitting tube according to claim 1, characterized in that: The shell structure is provided with a side wall extending portion on the side wall corresponding to the first cavity for extending the path length of the gas entering the first cavity, and the shape of the electrode bracket at the side wall extending portion is the same as the shape of the side wall extending portion.

4. The highly weather-resistant SMD LED light-emitting tube according to claim 2, characterized in that: The first cavity is filled with a first packaging glue, the electrode bracket is located at the connection portion between the inner wall and the outer wall, and at the transition portion between the first cavity and the second cavity, and the surface formed after the first packaging glue is cured covers the connection portion between the inner wall and the outer wall of the electrode bracket; The second cavity is filled with second packaging glue.

5. A packaging process for a highly weather-resistant SMD LED light-emitting tube, used for preparing a highly weather-resistant SMD LED light-emitting tube as claimed in any one of claims 1 to 4, characterized in that: include: S10, setting a bracket mold for punching the electrode bracket, wherein the shape of the cavity of the bracket mold is the same as the shape of the electrode bracket to be formed; A plastic mold for injection molding the shell structure is provided, wherein the shape of the cavity of the plastic mold is the same as the shape of the shell structure to be molded; S20, using a punching machine in conjunction with a bracket mold to punch a copper sheet or an iron sheet into an electrode bracket, and then silver-plating the surface of the electrode bracket; S30, placing the electrode bracket in a plastic mold, and using an injection molding machine to injection mold a shell structure with the electrode bracket; S40, using a die bonding machine to fix the red LED flip chip, the green LED flip chip, and the blue LED flip chip on the corresponding electrode brackets; S50, dripping a first packaging glue into the first cavity using a glue dispenser, and then dripping a second packaging glue into the second cavity after the first packaging glue is initially cured, and curing the second packaging glue.

6. The packaging process of a highly weather-resistant SMD LED light-emitting tube according to claim 5, characterized in that: The surface of the electrode bracket is coated with conductive solder, and the red LED flip chip, the green LED flip chip, and the blue LED flip chip are fixedly connected to the electrode bracket through the conductive solder.

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