TWI555948B - LED bulb - Google Patents

Description

LED bulb

The present invention relates to a light-emitting diode (LED) lamp, and more particularly to an omni-directional LED bulb having a large-angle light-emitting characteristic or called full-circumferential light.

When the LED was used in the 1960s, it was used as a display light and a signal light because of its low power. However, in recent years, its brightness and power have been significantly improved. LED luminaires are the lowest power consumption of current illuminators, and are therefore the most suitable for green lighting. However, because of the light source of the LED and the emitted light shape, it is not only a point light source but also has directivity compared to a conventional light source. Although it has the advantage of extremely low power consumption, it is necessary to spread the point source and apply it to illumination. Other designs and improvements are needed.

As described above, since the LED has high directivity, it is difficult to apply to a case where a wider illumination range is required. If you need to achieve a large illumination angle or a full-circumferential effect, you need to use reflection, refraction, and scattering of LED light, or extend the length of the basic light-emitting surface to achieve full-period light structure. Therefore, it is necessary to increase the cost and add more parts. In terms of geometric improvement, in order to achieve full-circumference, it is common to arrange the LED lighting module on the side of the columnar or tapered heat sink, that is, to increase the light by mounting the LED die on the side. angle. Generally, the angle of the side surface of the LED die and the horizontal plane is generally larger, about 35 to 90 degrees, and thus the columnar or tapered heat sink has a considerable height, so that the overall height of the LED bulb is not easy to be small. There are problems with oversize.

In view of this, the present invention provides an LED bulb lamp, which is improved in structural design and can achieve a large illumination angle without increasing the height of the LED bulb.

The invention provides an LED bulb lamp, wherein an LED stage with an inclined plane is used, and a lamp cover suitable for physical characteristics and geometric structure can effectively achieve the effect of full-circumference (≧270 degrees) without greatly increasing the LED. The height of the bulb is in line with the trend of miniaturization.

An LED bulb according to an embodiment of the invention includes a lamp cover, a power connector, an LED lighting module, a power conversion module, and a heat sink. The power conversion module is electrically connected to the power connector and the LED lighting module, and converts the alternating current into direct current to provide power required for the LED lighting module. The heat sink includes an upper surface including at least two inclined plane LED stages for carrying the LED lighting module. When the lampshade of the LED bulb is disposed vertically upward, the angle formed by the inclined plane and the horizontal plane ranges from 10 to 25 degrees, and the LED bulb has an illumination angle of at least 270 degrees. In particular, the LED bulb of the present invention uses a smaller tilt angle LED stage, which only slightly increases the height of the heat sink, so the overall height of the LED bulb is not greatly increased, and is suitable for a miniaturized design.

In one embodiment, the lampshade has a haze of at least 90% for obtaining a larger LED illumination angle of the LED bulb.

In one embodiment, the lamp cover protrudes laterally relative to the heat sink base. Specifically, the ratio of the diameter of the upper surface of the heat sink to the diameter of the lamp cover at the widest point is 50-70%.

In one embodiment, the heat sink further includes an annular sidewall, the upper edge of the annular sidewall is connected to the periphery of the upper surface, and the heat sink is a structure having an upper width and a lower width.

In one embodiment, the LED bulb further includes a base that cooperates with a periphery of the opening of the shade.

In one embodiment, the highest point of the heat sink is higher than the junction of the lampshade and the base, and the vertical distance between the highest point of the heat sink and the junction of the lampshade and the base is about 2.5-15 mm.

In one embodiment, the junction of the lampshade and the base forms a tangent to the cover housing, and the angle between the tangent and the vertical line is 30 to 60 degrees.

In one embodiment, the base is a hollow structure having an upper width and a lower width, and the slope of the inner side wall coincides with the slope of the annular side wall of the heat sink seat, so that a main portion of the heat sink seat can be accommodated in the base.

In one embodiment, the light cover has a light transmittance of at least 75%.

In one embodiment, the upper surface of the heat sink includes 3-8 inclined planes for carrying the LED lighting module.

The invention improves the tilt angle of the LED lighting module on the heat sink, and cooperates with the suitable lampshade to effectively achieve the effect of large light exit angle or full illumination. In addition, because the angle of the inclined plane of the LED lighting module on the heat sink of the present invention is not more than 25 degrees, the height of the heat sink is not excessively high. Therefore, the height of the LED bulb produced in accordance with the present invention is not too high due to the need for full illumination, and does not meet the demand for miniaturization.

The above and other technical contents, features and advantages of the present invention will become more apparent from the following description.

1 and 2, FIG. 1 shows a schematic perspective view of an LED bulb 10, and FIG. 2 shows an exploded perspective view of the LED bulb 10. The LED bulb 10 includes a lamp cover 11, a heat sink 12, a power conversion module 13, a base 14, a power connection base 15, and an LED lighting module 16. In this embodiment, the lower edge of the lamp cover 11 is provided with a threaded connection structure, which can be matched with the corresponding thread structure disposed on the upper edge of the base 14, that is, the lower edge structure of the base 14 matches the peripheral structure of the opening of the lamp cover 11 to carry out the two. Combine. The manner of bonding the lampshade 11 and the base 14 can also be other fastening methods or bonding methods, and is not limited to the embodiment. The shape of the lampshade 11 may be, but not limited to, a spherical shape, and other shapes such as an ellipse or a square may be used. The upper surface 17 of the heat sink 12 includes two inclined plane LED stages 18 and 19 for carrying the LED lighting module 16 and providing heat dissipation. The number of LED lighting modules is not limited, but it is usually determined by the number of inclined planes for easy production. In addition, the heat sink 12 further includes an annular sidewall 20 that connects the periphery of the upper surface 17, and the annular sidewall 20 has a structure that is wide and narrow. Overall, the heat sink 11 is also a structure that is wide and narrow. A hollow chamber is formed between the annular side wall 20 and the upper surface 17. The base 14 is an annular hollow structure with an upper width and a lower width, and the inclination of the inner side wall of the annular hollow structure coincides with the inclination of the periphery of the annular side wall 20 of the heat dissipation seat 12, so that the heat dissipation seat 12 can be disposed on the base 14 Among them. The power conversion module 13 is disposed in the hollow space formed by the heat sink 12 and the base 14. The two ends are respectively connected with the LED light emitting module 16 and the power connection base 15 by wires, and the alternating current can be converted into direct current to provide the LED light emitting mode. Group 16 illuminates the required power. The upper end of the power connector 15 is coupled to and coupled to the lower edge of the base 14.

3 shows a cross-sectional view of the LED bulb 10, and the power conversion module 13 is omitted in order to clearly show the position and relationship between the members. The lampshade 11 can be in the form of a transparent or translucent matte surface to achieve an effect of nearly 90% transmittance or semi-light transmission. In this embodiment, the lampshade 11 is substantially circular or elliptical, and the boundary between the bottom of the lampshade 11 and the base 14 cannot exceed the height of the LED die in the LED lighting module 16 so as not to hinder the emission of light. A hollow chamber 21 is formed between the annular side wall 20 and the upper surface 17 of the heat sink 12, which can be combined with the hollow portion of the lower half of the base 14 to accommodate the power conversion module 13.

FIG. 4 shows a side cross-sectional view of the heat sink 12. When the heat sink 12 is laid flat, that is, when the lampshade of the LED bulb 10 is vertically disposed upward, the angle between the plane of the LED stages 18 and 19 on the upper surface 17 of the heat sink 12 and the horizontal plane is between 10~ 25 degrees, or especially 12 degrees, 15 degrees or 20 degrees.

In order to obtain a larger LED light-emitting angle, for example, to achieve the effect of full-circumference light (≧270 degrees), it is preferable to use a lamp cover having a high light diffusing rate. The "light diffusion" of illumination is a phenomenon in which the light of multiple light sources is ghosted by interference to make the vision difficult to distinguish. Generally, as long as the material that can interfere with the light advances has a diffusing effect on the light, the diffusion performance of the light depends on the light. In the ratio of the refractive index of the interference material to the refractive index of the substrate, the larger the ratio, the better the diffusion, but at the same time, a good light transmittance must be considered. The high diffusivity lampshade can be added in the production process, and can be evenly distributed in the lampshade plate. When the light passes through the plate, the optical effect of refraction, reflection, scattering, etc. occurs when the diffusing particles meet. The effect of diffusivity or large illumination angle. In general, the higher the light diffusivity or haze, the higher the wide angle scattering. The lampshade 11 of the present invention must have both high light transmittance and high light diffusivity, for example, a light transmittance of 75% or more, such as 80% or 85% in particular, a haze of 90% or more, or especially 92. % or 95%, the above light transmittance and haze are data measured according to ASTM D1003, that is, the measurement of the lampshade raw material in the form of a flat plate. That is to say, when the lamp cover 11 is selected in the present invention, while ensuring high light transmittance, it is also necessary to simultaneously consider the optimal light diffusion effect. Some high-haze lampshades sometimes have insufficient light transmittance. Depending on the current popularity of high-power or high-lumen LEDs, higher-power LED lighting modules can be used, for example, 8W or more. The problem of low lumens of the LED bulb caused by insufficient light transmittance is compensated.

Referring to Figure 3, in addition to using a high haze of the lampshade 11 to increase the full-circumference effect, the structural design of the lampshade 11 and the base 14 is also an important consideration. In this embodiment, the base 14 adopts a wide and narrow design to provide an unobstructed emission space. The angle φ1 of the side wall of the base 14 and the vertical line is between 15 and 45 degrees, or particularly 20 or 30 degrees. . In addition, the width or diameter of the lamp cover 11 at the widest point is larger than the width or diameter of the upper surface 17 of the heat sink 12, and a large light-emitting scattering effect is produced by the lateral cover of the lamp cover 11 protruding laterally from the heat sink 12. In one embodiment, the diameter A at the widest point of the lampshade 11 and the diameter B of the upper surface of the heat sink 12 have a better ratio range, and the B/A ratio is between 50% and 70%, or particularly 55%, 60%. Or 65%. From another point of view, since the base 14 is opaque, the junction of the lamp cover 11 and the base 14 represents the lowest point of light transmission, and the angle φ2 between the junction and the tangential line of the cover 11 and the vertical line can also be The size of the width of the lamp cover 11 is shown, and the larger the angle φ2, the more the lamp cover 11 is protruded laterally, thus producing a larger angle of illumination. In one embodiment, φ2 ranges from 30 to 60 degrees, and may also be 35 degrees, 40 degrees, 45 degrees, 50 degrees, or 55 degrees. In addition, the higher the LED lighting module 16 is, the larger the angle of the lowest point of light transmission at the boundary between the lampshade 11 and the base 14 is, and thus a larger illumination angle can be obtained. Therefore, the highest point of the heat sink 12 must be higher than the junction of the lamp cover 11 and the base 14, and the higher the distance H between the apex of the upper surface 17 of the heat sink 12 and the junction of the lampshade 11 and the base 14, the more the illumination angle can be obtained. Big. For example, the heat sink 12 is displaced upward without changing the tilt angle θ, thereby obtaining a larger light-emitting angle. In one embodiment, H is in the range of about 2.5-15 mm, and may also be in particular 3 mm, 6 mm, 9 mm or 12 mm. The foregoing dimensions are for a general-sized bulb lamp. If the base 14 is relatively wide, the vertical distance between the highest point of the heat sink 12 and the junction of the lampshade 11 and the base 14 can be up to 30 mm.

In summary, how to obtain a better full-circumference effect (the illuminating angle is greater than or equal to 270 degrees), the geometry part depends mainly on the angle θ of the inclined plane and the horizontal plane where the LED stages 18 and 19 are located, the lampshade 11 and the base 14 The angle between the junction and the tangential line of the housing of the lampshade 11 and the vertical line φ2, and the distance H between the apex of the upper surface 17 of the heat sink 12 and the junction of the lampshade 11 and the base 14 are. In addition, in the physical properties or material parts, the lampshade 11 needs to have a haze of 90% or more to provide a larger illumination angle. Table 1 below shows examples of illuminating angles corresponding to different θ, φ2, and H conditions, where θ = 10 ^o or 20 ^o , φ 2 = 30 ^o or 60 ^o , and H = 3, 5, or 8 mm. In addition, the angle of illumination of the lampshade with a large inclination angle or a laterally convex shape is shown in Table 2, where φ2 = 60 ^o , θ = 10 ^o , 15 ^o or 20 ^o , and H = 3, 5 or 8 mm. The lampshade of the examples in Tables 1 and 2 had a light transmittance of 80% and a haze of 92%. The illumination angle or luminous intensity distribution of the full perimeter is in accordance with Energy Star Lamps V1.1, which specifies that the number of lumens in the 135-180 ^o area on the back of the bulb should not be Less than 5% of the total lumens. It can be concluded from Table 1 and Table 2 that the higher the position of the heat sink seat, the larger the tilt angle of the LED stage in the heat sink seat, and the more laterally the lamp cover protrudes, the larger the light angle can be obtained. LED bulbs can be illuminated at angles of 270 to 320 ^o , such as 280 ^o and 290 ^o , in particular.

Table 1         <TABLE border="1" borderColor="#000000" width="_0003"><TBODY><tr><td> </td><td> H=3mm </td><td> H=8mm </ Td><td> H=13mm </td></tr><tr><td> θ=10^o; φ2=30^o</td>< Td> 270^o</td><td> 284^o</td><td> 297^o</td></tr ><tr><td> θ=20^o; φ2=30^o</td><td> 286^o</td> <td> 290^o</td><td> 299^o</td></tr><tr><td> θ=10<sup>o< /sup>; φ2=60^o</td><td> 284^o</td><td> 299^o</td ><td> 310^o</td></tr><tr><td> θ=20^o; φ2=60^o </td><td> 291^o</td><td> 310^o</td><td> 318^o</ Td></tr></TBODY></TABLE>

Table 2         <TABLE border="1" borderColor="#000000" width="_0004"><TBODY><tr><td> </td><td> θ=10^o</td> <td> θ=15^o</td><td> θ=20^o</td></tr><tr><td> φ2=60< Sup>o</sup>; H=3mm </td><td> 285^o</td><td> 288^o</td><td> 291^o</td></tr><tr><td> φ2=60^o; H=8mm </td><td> 299^o</td><td> 305^o</td><td> 310^o</td></tr><tr><td> Φ2=60^o; H=13mm </td><td> 310^o</td><td> 315^o</td ><td> 318^o</td></tr></TBODY></TABLE>

Figure 5 shows a schematic view of a heat sink 30 of another embodiment, which is an embodiment with three LED stages. The upper surface 31 of the heat sink 30 includes three inclined plane LED stages 33, 34 and 35 for carrying the LED lighting module and providing heat dissipation. In addition, the heat sink 30 further includes an annular side wall 32 that connects the periphery of the upper surface 31. The annular side wall 32 and the upper surface 31 form a hollow chamber having an opening below. Compared with the two inclined planes of the first embodiment, the embodiment adopts three inclined planes, and the illumination of the LED will be more uniform. In addition to the 2 or 3 inclined planes of the foregoing embodiments, the heat sink of the present invention can be designed according to different needs. In particular, the heat sink of the present invention includes two or more inclined planes for carrying the LED lighting module and providing a heat dissipation function.

The invention utilizes the inclined plane of the small angle to achieve the effect of the full illumination of the illumination angle of at least 270 degrees, and because of the inclined plane design of the small angle, the height of the heat sink can be effectively reduced, thereby reducing the overall height of the LED bulb. Therefore, it can be used as the basis for the miniaturization design of LED bulbs.

The technical contents and technical features of the present invention have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should be construed as being limited by the scope of the appended claims

10‧‧‧LED Bulb
11‧‧‧shade
12‧‧‧ Heat sink
13‧‧‧Power Conversion Module
14‧‧‧Base
15‧‧‧Power connector
16‧‧‧LED lighting module
17‧‧‧Upper surface
18, 19‧‧‧LED stage
20‧‧‧Circular side wall
21‧‧‧ hollow room
30‧‧‧ Heat sink
31‧‧‧ upper surface
32‧‧‧Ring side wall
33, 34, 35‧‧‧LED stage

1 is a schematic perspective view of an LED bulb according to an embodiment of the present invention; FIG. 2 is an exploded perspective view of an LED bulb according to an embodiment of the present invention; FIG. 3 is a side view of an LED bulb according to an embodiment of the present invention; 4 is a side view of a heat sink of an LED bulb according to an embodiment of the present invention; and FIG. 5 is a perspective view of a heat sink of an LED bulb according to another embodiment of the present invention.

10‧‧‧LED Bulb

11‧‧‧shade

12‧‧‧ Heat sink

13‧‧‧Power Conversion Module

14‧‧‧Base

15‧‧‧Power connector

16‧‧‧LED lighting module

17‧‧‧Upper surface

18, 19‧‧‧LED stage

20‧‧‧Circular side wall

Claims (9)

An LED bulb lamp comprises: a lamp cover; a power connection base; an LED illumination module; a power conversion module, electrically connecting the power connection base and the LED illumination module, providing power required by the LED illumination module; and a heat sink The heat sink includes an upper surface, the upper surface includes at least two inclined plane LED carriers for carrying the LED light emitting module, wherein the heat sink further comprises an annular sidewall, and the upper edge of the annular sidewall is connected to the upper surface a periphery of the surface, and the heat sink is a structure having an upper width and a lower width; wherein when the lamp cover of the LED bulb is vertically disposed upward, the angle formed by the inclined plane and the horizontal plane ranges from 10 to 25 degrees, and the LED ball The bulb has an illumination angle of at least 270 degrees. The LED bulb of claim 1, wherein the shade has a haze of at least 90%. The LED bulb according to claim 1, wherein a ratio of a diameter of the upper surface of the heat sink to a diameter of the widest portion of the lamp cover is 50 to 70%. The LED bulb according to claim 1, further comprising a base that is coupled to a circumference of the opening of the lampshade. The LED bulb according to claim 4, wherein the highest point of the heat sink is higher than the junction of the lamp cover and the base, and the vertical distance between the highest point of the heat sink and the junction of the lamp cover and the base is 2.5 to 15 mm. The LED bulb of claim 4, wherein the junction of the lampshade and the base forms a tangent to the lampshade housing, the angle of the tangent to the vertical line being between 30 and 60 degrees. The LED bulb according to claim 4, wherein the base is a hollow structure having an upper width and a lower width, and a slope of an inner side wall thereof matches a slope of the annular side wall of the heat sink seat, so that a main portion of the heat sink seat Can be placed in the base. The LED bulb of claim 1, wherein the lamp cover has a light transmittance of at least 75%. The LED bulb of claim 1, wherein the upper surface of the heat sink comprises 3-8 inclined planes for carrying the LED lighting module.