COB light source and LED lamp
By adding an insulating protection structure to the COB light source, the creepage distance between the electrode pad and the contour edge of the metal substrate is increased, the problem of the insulating layer falling off due to leakage current is solved, and the service life of the COB light source is improved.
Patent Information
- Application Number
- CN202421662855.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-12
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2034-07-12
AI Technical Summary
The insulating layer of the COB light source of the related art falls off due to the generation of leakage current, resulting in a shortening of the service life of the COB light source.
A COB light source is designed to add an insulating protection structure, which is located between the electrode pad and the contour edge of the metal substrate to increase the creepage distance between the electrode pad and the contour edge of the metal substrate.
By adding an insulating protection structure, the probability of leakage current generated by creepage between the electrode pad and the contour edge of the metal substrate is reduced, thereby preventing the insulating layer from falling off and improving the service life of the COB light source.
Smart Images
Figure CN222966145U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the technical field of lighting devices, and particularly relates to a COB light source and an LED lamp. Background Art
[0002] For the related COB light source (i.e., Chip On Board Light), in order to improve the efficiency of the integrated light source, the output voltage of the driver needs to be as high as 400V or above, collectively referred to as the 400V COB light source. In the 400V COB light source, the insulating layer is likely to fall off due to the generation of leakage current, resulting in a shortened service life of the COB light source. Summary of the Utility Model
[0003] The purpose of this application is to provide a COB light source and an LED lamp, aiming to solve the problem that the insulating layer of the related COB light source falls off due to the generation of leakage current, resulting in a shortened service life of the COB light source.
[0004] To achieve the above purpose, according to the first aspect of this application, the technical solution adopted is: A COB light source, comprising:
[0005] A metal substrate;
[0006] An LED chip, mounted on the surface of the metal substrate;
[0007] An insulating layer, provided on at least one surface of the metal substrate;
[0008] An electrode pad, provided on the insulating layer, and electrically connected to the LED chip through a welding wire;
[0009] Characterized in that, the COB light source further comprises:
[0010] An insulation protection structure, provided on the insulating layer, and the insulation protection structure is located between the electrode pad and the contour edge of the metal substrate to increase the creepage distance between the electrode pad and the contour edge of the metal substrate.
[0011] In some embodiments of this application, the insulation protection structure includes a first insulation enclosure wall, the first insulation enclosure wall is provided on the surface of the insulating layer, and the first insulation enclosure wall surrounds the electrode pad and the LED chip.
[0012] In some embodiments of this application, the height of the first insulation enclosure wall on the insulating layer is greater than the height of the electrode pad on the insulating layer.
[0013] In some embodiments of this application, the insulation protection structure includes an insulation covering layer, the insulation covering layer is provided on the surface of the insulating layer, and the insulation covering layer covers the electrode pad and the welding wire.
[0014] In some embodiments of the present application, the insulation protection structure includes a second insulation enclosure that surrounds the electrode pad, and the height of the second insulation enclosure on the insulation layer is greater than the height of the electrode pad on the insulation layer.
[0015] In some embodiments of the present application, the insulation protection structure includes a third insulation enclosure that is disposed on the circumferential side surface of the insulation layer, and the third insulation enclosure extends and covers the circumferential side surface of the metal substrate.
[0016] In some embodiments of the present application, the minimum distance between the contour edge of the vertical projection of the electrode pad on the surface of the metal substrate and the contour edge of the metal substrate is greater than or equal to 3 mm.
[0017] In some embodiments of the present application, the thickness range of the insulation layer is 0.1 mm - 1.0 mm.
[0018] In some embodiments of the present application, a barrier portion in a closed curve is provided between the LED chip and the electrode pad. The barrier portion surrounds the LED chip, and the space surrounded by the barrier portion is filled with a fluorescent layer that covers the LED chip.
[0019] According to the second aspect of the present application, an LED lamp is provided. Among them, the LED lamp includes the COB light source as described above.
[0020] The present application has at least the following beneficial effects:
[0021] The COB light source provided by the present application is powered on. The driver outputs a voltage to the electrode pad, and the electrode pad is electrically connected to the LED chip through a wire, so that the LED chip emits light when powered on. During the process of the LED chip emitting light, the LED chip is mounted on the surface of the metal substrate, enabling the LED chip to dissipate heat quickly through the metal substrate. The insulation layer disposed on the surface of the metal substrate provides an installation position for the electrode pad that is insulated from the metal substrate. Moreover, the COB light source of the present application is additionally provided with an insulation protection structure that is located between the electrode pad and the contour edge of the metal substrate, thereby increasing the creepage distance between the electrode pad and the contour edge of the metal substrate. In this way, when the COB light source is powered on, the probability of creepage occurring between the electrode pad and the contour edge of the metal substrate and generating leakage current can be reduced, thereby preventing the insulation layer of the COB light source from falling off due to the generation of leakage current and improving the service life of the COB light source. Description of the Drawings
[0022] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.
[0023] Figure 1 Schematic three-dimensional structure diagram of the COB light source according to Embodiment 1 of the present application;
[0024] Figure 2 is Figure 1 Schematic cross-sectional view of the shown COB light source;
[0025] Figure 3 is Figure 2 Enlarged schematic view of part A in ;
[0026] Figure 4 Schematic three-dimensional structure diagram of the COB light source according to Embodiment 2 of the present application;
[0027] Figure 5 is Figure 4 Schematic cross-sectional view of the shown COB light source;
[0028] Figure 6 Schematic cross-sectional view of the COB light source according to Embodiment 3 of the present application;
[0029] Figure 7 Schematic cross-sectional view of the COB light source according to Embodiment 4 of the present application.
[0030] Among them, the reference numerals in the figure are as follows:
[0031] 10, metal substrate; 20, LED chip; 30, insulating layer; 40, electrode pad; 50, welding wire; 60, insulating protection structure; 61, first insulating enclosure; 62, insulating covering layer; 63, second insulating enclosure; 64, third insulating enclosure; 70, fluorescent layer; 71, blocking part. Detailed implementation manners
[0032] The following will describe in detail the embodiments of the present application. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as a limitation to the present application.
[0033] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present 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, and thus should not be construed as a limitation to the present application.
[0034] In addition, terms such as "first", "second", etc. are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality" is two or more unless otherwise specifically defined.
[0035] In the present application, unless otherwise clearly specified and limited, terms such as "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.
[0036] Embodiment 1:
[0037] Such as Figure 1 And Figure 2As shown in the figure, the COB light source provided in the first embodiment of the present application includes a metal substrate 10, an LED chip 20, an insulating layer 30, an electrode pad 40, and an insulating protection structure 60. The LED chip 20 is mounted on the surface of the metal substrate 10, and the electrodes of the LED chip 20 are located on the side of the LED chip 20 facing away from the metal substrate 10. Therefore, the LED chip 20 and the metal substrate 10 cannot conduct electricity. The insulating layer 30 is disposed on at least one surface of the metal substrate 10. Moreover, the insulating layer 30 must be provided on the surface of the metal substrate 10 where the LED chip 20 is located. Whether to provide the insulating layer on the surface of the metal substrate 10 facing away from the LED chip 20 is determined according to actual needs. Herein, the following-mentioned insulating layer 30 refers to the insulating layer 30 provided on the surface of the metal substrate 10 where the LED chip 20 is located. The insulating layer 30 is an independent component relative to the metal substrate 10. When preparing the insulating layer 30 provided on the surface of the metal substrate 10 where the LED chip 20 is located, a hollow space for avoiding the LED chip 20 needs to be cut out on the insulating layer 30, and then the insulating layer 30 is pasted onto the surface of the metal substrate 10. The electrode pad 40 is disposed on the insulating layer 30, and the electrode pad 40 is electrically connected to the LED chip 20 through a wire 50. In the related art, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is the shortest distance measured along the surface of the insulating layer 30. However, the COB light source provided in the present application is provided with an insulating protection structure 60. The insulating protection structure 60 is disposed on the insulating layer 30, and the insulating protection structure 60 is located between the electrode pad 40 and the contour edge of the metal substrate 10. Compared with the COB light source in the related art, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is increased.
[0038] "Creepage" means that when the performance of the insulating material deteriorates, due to external factors such as weather, such as high air humidity, continuous cloudy and rainy seasons, humid environments, etc., an arc like water pattern is generated between the charged metal part and the insulating material and climbs along the outer skin. The "creepage distance" refers to the shortest space distance measured along the surface of the insulating material between two conductive components, the distance of discharge along the insulating surface, that is, the leakage distance. Therefore, in the COB light source provided in the present application, the shortest path from the electrode pad 40 to the contour edge of the metal substrate 10 along the surface of the insulating layer 30 and the surface of the insulating protection structure 60 is the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10.
[0039] When the COB light source provided by this application is powered on, the driver outputs voltage to the electrode pad 40. The electrode pad 40 is electrically connected to the LED chip 20 through a wire 50, so that the LED chip 20 is powered on and emits light. During the process of the LED chip 20 emitting light, the LED chip 20 generates heat. The LED chip 20 is mounted on the surface of the metal substrate 10, enabling the LED chip 20 to directly transfer the heat to the metal substrate 10, and thus quickly dissipate heat through the metal substrate 10. The insulating layer 30 provided on the surface of the metal substrate 10 provides an installation position for the electrode pad 40 that is insulated from the metal substrate 10.
[0040] In order to improve the reflectivity of the surface of the metal substrate 10 to the light emitted by the LED chip 20, therefore, the COB light source adopts a mirror silver-aluminum substrate. That is, the main body of the metal substrate 10 is an aluminum substrate, and silver is plated on one side surface of the aluminum substrate to form a mirror surface, improving the reflectivity to the light emitted by the LED chip 20. The reflectivity can reach more than 95%, and the light emitted by the LED chip 20 can be better reflected. Moreover, the insulating layer 30 is pasted on one side of the silver-plated layer of the metal substrate 10. Due to the existence of the silver-plated layer, when creepage occurs between the electrode pad 40 and the contour edge of the metal substrate 10, resulting in leakage current, it will cause Ag migration and damage the adhesive layer between the insulating layer 30 and the surface of the metal substrate 10, leading to a decrease in the bonding strength and causing the insulating layer 30 to fall off from the surface of the metal substrate 10.
[0041] In order to prevent the insulating layer 30 of the COB light source from falling off due to the generation of leakage current, therefore, the COB light source of this application is additionally provided with an insulation protection structure 60. The insulation protection structure 60 is located between the electrode pad 40 and the contour edge of the metal substrate 10. Compared with the COB light source in the related art, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is increased. In this way, when the COB light source provided by this application is powered on, the probability of creepage occurring between the electrode pad 40 and the contour edge of the metal substrate 10, resulting in leakage current, can be reduced, thereby preventing the insulating layer 30 of the COB light source from falling off due to the generation of leakage current and improving the service life of the COB light source.
[0042] Such as Figure 1 and Figure 2As shown, the insulation protection structure 60 includes a first insulation enclosure 61. The first insulation enclosure 61 is disposed on the surface of the insulation layer 30 facing away from the metal substrate 10. The first insulation enclosure 61 has a certain thickness and protrudes in the direction away from the metal substrate 10 of the insulation layer 30. Moreover, the first insulation enclosure 61 surrounds the electrode pad 40 and the LED chip 20. In this way, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is increased by the added first insulation enclosure 61. It is not easy for creepage to occur between the electrode pad 40 and the contour edge of the metal substrate 10 to generate leakage current, thereby preventing the insulation layer 30 of the COB light source from falling off due to the generation of leakage current and improving the service life of the COB light source.
[0043] As Figure 2 and Figure 3 shown, the height of the first insulation enclosure 61 on the insulation layer 30 is greater than the height of the electrode pad 40 on the insulation layer 30. In this way, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is further increased, further reducing the probability of creepage occurring between the electrode pad 40 and the contour edge of the metal substrate 10 to generate leakage current, preventing the insulation layer 30 from falling off due to the generation of leakage current, and improving the service life of the COB light source.
[0044] In the COB light source of Embodiment 1 of the present application, the minimum distance between the contour edge of the vertical projection of the electrode pad 40 on the board surface of the metal substrate 10 and the contour edge of the metal substrate 10 is greater than or equal to 3 mm. As Figure 1 shown, the metal substrate 10 has a square contour shape. Moreover, in order to reasonably utilize other board surface positions of the metal substrate 10 except for the board surface positions necessary for mounting the LED chip 20, the electrode pad 40 is generally disposed at the board surface position in the corner area of the square contour shape. In this way, there are a distance L1 and a distance L2 between the electrode pad 40 and the two adjacent sides of this corner area respectively. On the basis of reasonably utilizing the board surface position of the metal substrate 10, through experiments, the appropriate dimensions between the contour edge of the metal substrate 10 and the electrode pad 40 are determined, L1≥3 mm, L2≥3 mm. Preferably, in the COB light source provided in the present application, L1 = L2 = 3 mm.
[0045] As Figure 3 shown, the thickness H of the insulation layer 30 ranges from 0.1 mm to 1.0 mm. Preferably, the thickness H of the insulation layer 30 is 0.3 mm, which is thicker than the thickness of the insulation layer of the COB light source in the related art, thereby being able to assist in increasing the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10.
[0046] In order to enable the light emitted by the LED chip 20 to be evenly irradiated for illumination, making the illumination light soft and non-glare. Therefore, asFigure 1 and Figure 2 As shown, a barrier portion 71 in a closed curve is provided between the LED chip 20 and the electrode pad 40. Among them, the barrier portion 71 is arranged along the circumferential edge of the hollow space of the insulating layer 30, that is, the barrier portion 71 surrounds the LED chip 20, and a fluorescent layer 70 is filled in the space surrounded by the barrier portion 71, and the fluorescent layer 70 covers the LED chip 20. The light emitted by the LED chip 20 is refracted after being guided by the fluorescent layer 70 for propagation to perform illumination, so that the illumination light is soft and non-glare. Since the thickness of the insulating layer 30 is less than the thickness of the LED chip 20, in order to prevent the liquid fluorescent layer 70 from overflowing and spreading during filling, the barrier portion 71 is provided to surround the LED chip 20, and the height of the barrier portion 71 relative to the metal substrate 10 is greater than the thickness of the LED chip 20. In this way, the liquid fluorescent layer 70 is blocked by the barrier portion 71, so that the liquid fluorescent layer 70 will not overflow and spread. Moreover, the top surface of the filled fluorescent layer 70 covering the LED chip 20 is flush with the top of the barrier portion 71. Further, in the COB light source of this embodiment, the top of the barrier portion 71 is substantially flush with the top of the first insulating enclosure wall 61.
[0047] Embodiment Two:
[0048] Compared with the COB light source of Embodiment One, the COB light source of Embodiment Two has the following differences.
[0049] As Figure 4 and Figure 5 shown, the insulation protection structure 60 includes a second insulating enclosure wall 63, and the second insulating enclosure wall 63 surrounds the electrode pad 40. In this embodiment, the COB light source is provided with two electrode pads 40, and each electrode pad 40 is correspondingly surrounded by a second insulating enclosure wall 63. Moreover, the height of the second insulating enclosure wall 63 on the insulating layer 30 is greater than the height of the electrode pad 40 on the insulating layer 30. In this way, by providing the second insulating enclosure wall 63 to surround the electrode pad 40, the creepage distance between the electrode pad 40 and the contour edge of the metal substrate 10 is increased compared with the COB light source of the related art, thereby reducing the probability of creepage between the electrode pad 40 and the contour edge of the metal substrate 10 to generate leakage current, and preventing the insulating layer 30 of the COB light source from falling off due to the generation of leakage current, and improving the service life of the COB light source.
[0050] In the COB light source of Embodiment Two, as Figure 5 shown, the top of the barrier portion 71 is substantially flush with the top of the second insulating enclosure wall 63.
[0051] Compared with the COB light source of Embodiment One, except for the above differences, the remaining structures are the same and will not be elaborated here.
[0052] Embodiment Three:
[0053] Compared with the COB light source of Embodiment One, the COB light source of Embodiment Three has the following differences.
[0054] As Figure 6 shown, the insulation protection structure 60 includes an insulation covering layer 62. The insulation covering layer 62 is disposed on the surface of the insulation layer 30, and the insulation covering layer 62 covers the electrode pads 40 and the welding wires 50. In this embodiment, by covering the electrode pads 40 and the welding wires 50 with the insulation covering layer 62, the possibility of creepage and generation of leakage current between the electrode pads 40 and the contour edge of the metal substrate 10 is basically eliminated. This is also a way to increase the creepage distance. The creepage distance between the electrode pads 40 and the contour edge of the metal substrate 10 is close to infinity, and creepage and generation of leakage current basically do not occur unless the insulation covering layer 62 is broken down. In this way, it is possible to prevent the insulation layer 30 of the COB light source from falling off due to the generation of leakage current, and improve the service life of the COB light source.
[0055] Compared with the COB light source of Embodiment One, except for the above differences, the remaining structures are the same and will not be elaborated here.
[0056] Embodiment Four:
[0057] Compared with the COB light source of Embodiment One, the COB light source of Embodiment Four has the following differences.
[0058] As Figure 7 shown, the insulation protection structure 60 includes a third insulation enclosure 64. The third insulation enclosure 64 is disposed on the circumferential side surface of the insulation layer 30, and the third insulation enclosure 64 extends and covers the circumferential side surface of the metal substrate 10. That is, the third insulation enclosure 64 encloses the circumferential side surface of the insulation layer 30 and the circumferential side surface of the metal substrate 10. At this time, the creepage distance between the electrode pads 40 and the metal substrate 10 is the sum of the minimum distance from the electrode pads 40 along the surface of the insulation layer 30 to the circumferential side surface of the insulation layer 30 and the distance from the connection of the third insulation enclosure 64 with the surface of the insulation layer 30 to its end close to the metal substrate 10. This increases the creepage distance between the electrode pads 40 and the contour edge of the metal substrate 10 compared with the COB light source of the related art, thereby reducing the probability of creepage and generation of leakage current between the electrode pads 40 and the contour edge of the metal substrate 10, being able to prevent the insulation layer 30 of the COB light source from falling off due to the generation of leakage current, and improving the service life of the COB light source.
[0059] Compared with the COB light source of Embodiment One, except for the above differences, the remaining structures are the same and will not be elaborated here.
[0060] According to another aspect of the present application, an LED lamp is provided. Among them, the LED lamp includes the COB light source as described above.
[0061] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A COB light source, comprising: metal substrate(10); An LED chip (20) is mounted on the surface of the metal substrate (10); An insulating layer (30) is disposed on at least one surface of the metal substrate (10); An electrode pad (40) is disposed on the insulating layer (30), and the electrode pad (40) is electrically connected to the LED chip (20) via a welding wire (50); Characterized in that the COB light source also includes: An insulating protection structure (60) is arranged on the insulating layer (30), and the insulating protection structure (60) is located between the electrode pad (40) and the contour edge of the metal substrate (10) to increase the creepage distance between the electrode pad (40) and the contour edge of the metal substrate (10).
2. The COB light source according to claim 1, characterized in that: The insulating protection structure (60) comprises a first insulating wall (61), wherein the first insulating wall (61) is arranged on the surface of the insulating layer (30), and the first insulating wall (61) surrounds the electrode pad (40) and the LED chip (20).
3. The COB light source according to claim 2, characterized in that: The height of the first insulating surrounding wall (61) on the insulating layer (30) is greater than the height of the electrode pad (40) on the insulating layer (30).
4. The COB light source according to claim 1, characterized in that: The insulating protective structure (60) comprises an insulating covering layer (62), wherein the insulating covering layer (62) is arranged on the surface of the insulating layer (30), and the insulating covering layer (62) covers the electrode pad (40) and the welding wire (50).
5. The COB light source according to claim 1, characterized in that: The insulating protection structure (60) comprises a second insulating wall (63), the second insulating wall (63) surrounds the electrode pad (40), and the height of the second insulating wall (63) on the insulating layer (30) is greater than the height of the electrode pad (40) on the insulating layer (30).
6. The COB light source according to claim 1, characterized in that: The insulating protection structure (60) comprises a third insulating wall (64), wherein the third insulating wall (64) is arranged on the circumferential side of the insulating layer (30), and the third insulating wall (64) extends and covers the circumferential side of the metal substrate (10).
7. The COB light source according to any one of claims 1 to 6, characterized in that: The minimum distance between the contour edge of the vertical projection of the electrode pad (40) on the plate surface of the metal substrate (10) and the contour edge of the metal substrate (10) is greater than or equal to 3 mm.
8. The COB light source according to any one of claims 1 to 6, characterized in that: The thickness of the insulating layer (30) is in the range of 0.1 mm to 1.0 mm.
9. The COB light source according to claim 1, characterized in that: A barrier portion (71) in the form of a closed curve is provided between the LED chip (20) and the electrode pad (40); the barrier portion (71) surrounds the LED chip (20); a fluorescent layer (70) is filled in the space surrounded by the barrier portion (71); and the fluorescent layer (70) covers the LED chip (20).
10. An LED lamp, characterized in that: Comprising the COB light source as described in any one of claims 1-9.