HK1175518A - Heat sink device for lamp and led lamp comprising the same - Google Patents

Description

Heat dissipation device for lamp and LED lamp comprising same

Technical Field

The invention relates to the field of lighting lamps. More particularly, the invention relates to a heat dissipation device for a lamp and an LED lighting lamp including the same, wherein the heat dissipation device has high heat dissipation efficiency and a compact and light structure.

Background

As a solid light source with great development potential, LEDs are receiving more and more attention due to their advantages of long lifetime, firm structure, low power consumption, flexible overall dimensions, and the like. In recent years, LED lamps have become cheaper and cheaper, and thus have been used in various lighting fields instead of conventional lamps. However, the LED lamp itself generates a relatively large amount of heat during operation, and if the heat cannot be dissipated in time, the temperature of the LED light source will gradually rise and exceed the temperature range of stable operation, which will greatly affect the product performance and the service life of the LED light source, and thus limit the application range of the LED lamp in the illumination field to a certain extent.

Various approaches have been proposed in an attempt to solve the heat dissipation problem of LED lamps. Generally, an active or passive heat dissipation device is disposed on the LED lamp to cool the LED light source, so as to achieve a better working temperature. However, for the passive heat dissipation device, in order to improve the heat dissipation efficiency, the size of the heat dissipation device is often required to be increased to increase the heat dissipation area, which increases the volume and weight of the LED lamp. Although the size of the active heat dissipation device, such as a fan, can be reduced to some extent by using the active heat dissipation device, the active heat dissipation device also has the disadvantages of high noise, higher power consumption and easy dust accumulation.

Currently, a commonly used heat dissipating device generally includes a cylinder having a continuous side circumferential surface and a plurality of fins formed on the continuous side circumferential surface. The heat generated by the LED light sources is carried to the air by these heat sinks in an air-convection manner and is also dissipated to the surrounding air in a radiation heat manner. To increase the heat dissipation area, more heat sinks are usually required or the structure of the heat sink is improved to obtain better heat dissipation effect.

For example, chinese utility model patent No. zl200720122176.x, entitled "a radiator of LED lamp and LED lamp" discloses a radiator including a plurality of fins, there are two points A, B in the center of any fin in the radiator cross section, and these two points form a triangle with the central point of radiator cross section. Compared with a straight-bar toothed radiator, the structure of the radiator has the advantages that the radiating area is increased, and the radiating speed is accelerated. However, not only does this heat sink use more material to make the heat sink, but the heat sink is bulky, which makes the LED lamp bulky.

Another chinese patent application No. 201010177036.9, entitled "a heat sink and LED lamp using the same", discloses a heat sink including a heat sink body composed of a cylindrical heat sink base and heat sink fins arranged around the heat sink base, and an air passage having a central through hole, the air passage is fixedly connected to one side end face of the heat sink body, and the through hole is perpendicular to the end face of the heat sink body for air convection heat dissipation. The heat dissipation device adopts the air passage structure for air convection heat dissipation, so that the heat dissipation efficiency of the heat dissipation body is increased. However, the provision of the air duct structure makes the volume of the LED lamp become considerably large and the manufacturing cost increases.

The existing LED lamp has a heavy and complex heat dissipation structure, so that the lamp has a large volume and complex manufacturing procedures. Therefore, there is a need for an improvement of a heat dissipation device of an LED lamp in the illumination field, which can not only improve the heat dissipation efficiency and maintain the lamp in a stable working state, but also achieve a compact and light structure.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a novel heat dissipation device which can effectively solve the heat dissipation problem of an LED lamp and has the advantages of good heat dissipation effect, compact structure, small volume, light weight, production raw material cost saving and the like.

The invention aims to realize the following technical scheme, and provides a heat dissipation device for a lamp, which is characterized by comprising the following components:

a base in heat conductive connection with a heat source; and

a plurality of spaced apart legs extending from the base, the legs surrounding and defining a hollow cavity such that gaps are formed on a side periphery of the cavity.

In one embodiment of the invention, the base is annular and has a first end face, and the plurality of struts extend perpendicularly or obliquely from the first end face. In another embodiment of the present invention, the annular base has a second end surface from which a plurality of second struts extend perpendicularly or obliquely, the second struts surrounding and defining a hollow second cavity such that a plurality of gaps are formed on a lateral peripheral surface of the second cavity.

The heat dissipation device further comprises a supporting piece arranged inside the annular base, and a fixing piece used for bearing the LED light source and fixing the LED light source. The supporting piece is in threaded connection, clamping connection or integrated molding with the inner wall of the annular base.

The free ends of the plurality of legs may be slightly bent inwardly or outwardly so as to abut against an object without moving.

Another aspect of the invention relates to an LED lamp comprising at least one LED light source, a base that is insertable into the base and connectable to a power source, a control circuit, and a back cover that houses the control circuit, the LED lamp further comprising a heat sink of the invention, the LED light source being in conductive thermal contact with a base of the heat sink, the back cover housing the control circuit being at least partially received within a cavity defined by the plurality of posts.

The inner surface of the support post is separated from the outer surface of the rear cover by at least 1mm, so that the support post and the surrounding cold air perform convection heat dissipation.

In a preferred embodiment of the invention, the LED light fixture is a reflector lamp and the heat sink comprises a plurality of spaced first legs and a plurality of spaced second legs extending from the first end face and the second end face of the base, respectively, and surrounding the first cavity and the second cavity, respectively, defining a hollow. Wherein at least a portion of the rear cover containing the control circuitry is received within the first cavity and at least a portion of the reflector cup is received within the second cavity. Preferably, the second cavity is shaped and dimensioned to cooperate with the reflector cup such that the reflector cup is fully received within the second cavity. The inner surface of the first support and the outer surface of the rear cover are separated by at least 1mm, and the inner surface of the second support and the outer surface of the reflection cup are separated by at least 1mm, so that the supports and the surrounding cold air perform convection heat dissipation.

In another preferred embodiment of the invention, the luminaire comprises two heat sinks of the invention, the bases of which are fixedly connected together and the legs of the two heat sinks are oriented oppositely. The cavity of one radiator is used for receiving at least one part of the rear cover and the control circuit, and the cavity of the other radiator is used for receiving at least one part of the light reflecting cup. The inner surface of the pillar of the radiator is at least 1mm away from the outer surfaces of the reflection cup and the rear cover.

The heat sink may comprise a support disposed within the base, the LED light source being mounted on the support, or the LED light source being secured to a heat conductor mounted on the support.

Preferably, the free ends of the legs of the heat sink are slightly bent inward or outward so that the free ends rest against the outer surface of the rear cover and remain stationary.

The heat sink is made of a thermally conductive material and the back cover is made of a non-conductive material. The thermally conductive material may be selected from aluminum, aluminum alloys, ceramics, thermally conductive plastics, or graphite. The non-conductive material may be plastic or glass.

The heat radiator of the invention omits a column body of the continuous side peripheral surface and a heat radiating fin formed on the side peripheral surface of the prior heat radiator, adopts a hollow cavity body formed by a plurality of spaced pillars, and the cavity body is provided with a plurality of gaps, thereby being beneficial to air circulation. Specifically, the hot air which absorbs heat from the LED light source in the cavity of the heat dissipation device can be diffused out through the gaps, and the cold air can be supplemented subsequently, so that the aim of quickly dissipating heat through air convection is fulfilled, and the heat dissipation efficiency is greatly improved. In addition, the radiator has the advantages of simple structure, light weight and small volume, and saves a large amount of raw material cost.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.

Drawings

Fig. 1 is a perspective view illustrating a heat dissipation device according to an embodiment of the invention.

Fig. 2 is a front view of the heat sink shown in fig. 1.

Fig. 3 is a bottom view of the heat dissipating device shown in fig. 1.

Fig. 4 is a top view of the heat sink shown in fig. 1.

Fig. 5 is a perspective view showing an LED lamp according to a first embodiment of the present invention.

Fig. 6 is an exploded view of the LED lamp shown in fig. 5.

Fig. 7 is a perspective view showing an LED reflector lamp according to a second embodiment of the present invention.

Fig. 8 is an exploded view of the LED reflector lamp of fig. 7.

Detailed Description

Referring to fig. 1-4, a heat sink 100 is shown as a preferred embodiment of the present invention, the heat sink 100 including a base 110 having a first end surface 112 and a second end surface 114, and a plurality of spaced apart pillars 120 extending perpendicularly from the first end surface 112 of the base 110. Of course, the pillar may also extend obliquely or curvilinearly from the first end surface 112 of the base 110. In this embodiment, the base is annular, and the pillar is a rectangular cylinder. Of course, the base and the post may be of any shape, for example the post may be cylindrical.

As shown, the plurality of spaced-apart struts 120 surround and define a hollow cavity 122 having a plurality of gaps 126 formed on the lateral periphery of the cavity. The cross-sectional area of the support post and the gap between two adjacent support posts are determined according to the size of the lamp. The cross-sectional area of the strut is preferably not too small, otherwise a good heat conduction effect is not achieved; furthermore, the gap between the two struts is not too small, which would affect the air circulation and the heat convection effect.

The free ends 124 of the legs 120 may be slightly bent inward or outward so that when the heat sink 100 is installed in a light fixture, the free ends 124 may grip against other components of the light fixture, leaving the heat sink stationary. This will be discussed in more detail below.

As a variation, a plurality of spaced apart second struts extend from the second end face 114 of the base 110 and surround and define a hollow second cavity such that a plurality of gaps (not shown) are formed on the lateral periphery of the second cavity. The structure increases the design change of the lamp, and different parts of the lamp can be respectively arranged in two different cavities of the heat dissipation device according to actual needs or design requirements.

Referring to fig. 1, 3 and 4, the heat dissipating device 100 further includes a support 130 disposed inside the base 110, wherein the support 130 is composed of a bottom 132 and a boss 134 extending from the bottom 132. The bottom 132 may be bolted or snapped together with the inner wall of the base 110. Of course, the base 132 and the boss 134 may be integrally formed with the base 110. The center of the boss 134 is provided with a square recessed area 136, and one or more LED light sources can be directly fixed on the recessed area 136. Alternatively, one or more LED light sources are secured to the light source panel, which is then secured to the recessed area 136. Alternatively, one or more LED light sources are mounted on a light source panel that is secured to the heat sink of the light source, and the heat sink with the LED light sources secured thereto is secured to the recessed area 136. These are known to the person skilled in the art and will not be described in detail here.

The heat sink base 110, the pillars 120, and the supports 130 are all made of a thermally conductive material, such as aluminum, aluminum alloy, ceramic, thermally conductive plastic, or graphite. Thus, heat generated by the LED light source mounted in the recessed area 136 during operation is conducted through the support 130 and the base 110 to the support 120, causing the support 120 to heat up, and the support 120 to heat up surrounding air. Due to the gaps 126 of the heat dissipation device, the hot air can be diffused out through the gaps 126, and the cold air can be supplemented later after the hot air is diffused, so that the convection of the air is accelerated, and the heat dissipation effect is increased.

Fig. 5 and 6 show an LED lamp 200 according to a first embodiment of the present invention, the LED lamp 200 including the heat dissipation device 100 described above. The LED lamp 200 further comprises a glass bulb 210, an LED light source 220, a back cover 230 and a lamp cap 240, and a control circuit (not shown).

The glass bulb 210 may be a transparent glass bulb, or a silica gel-coated glass bulb, a twisted glass bulb, a frosted glass bulb, or the like may be selected as required. The base 240 may be designed as various sized bases as desired, such as E14, E26, E27, and the like. The control circuit may employ various control circuits known in the art, which are not essential to the present invention and will not be described in detail herein.

The LED light source 220 may be formed of one or more LED chips. In the present embodiment, the LED light source 220 is composed of a plurality of chip LEDs and is fixed on the light source panel 250. The LED light sources 220 and the light source panel 250 may be glued or secured together in any known mechanical manner. Then, the light source panel 250 to which the LED light sources 220 are fixed is fixed on the recess 136 of the heat sink. The fixing means may be any other means known in the art, and preferably the fixing means and the fixing means are capable of providing good heat conduction and heat dissipation, for example, the fixing means and the fixing means may be bonded together by using a highly viscous heat-dissipating oil.

The rear cover 230 is made of a non-conductive material, such as glass or plastic, and provides an insulating function. The rear cover 230 includes a housing 232 having a receiving cavity in which the control circuit is accommodated. A portion of the rear cover 230 is received with the control circuitry within the hollow cavity 122 of the heat sink 100 surrounded by the posts. In this embodiment, the free ends 124 of the pillars 120 of the heat sink 100 are slightly bent to abut and grip on the outer surface of the lower trapezoidal portion of the rear cover 230, so that the pillars 120 are kept stationary.

The outer surface of the housing 232 of the rear cover 230 is spaced from the inner surface of the pillar 120 of the heat sink 100, preferably by at least 1 mm. Thereby, a space is defined between the housing 232 and the support column 120, which is more favorable for convection of air, so that hot air can be more rapidly emitted.

The second end 114 of the heat sink 100 and the glass envelope 210 may be joined together in any manner known in the art, such as snap-on screws or glue.

The light source panel 250 and the heat sink 100 are preferably made of a thermally conductive material, such as aluminum, aluminum alloy, ceramic, thermally conductive plastic or graphite.

Since the light source panel 250 with the LED light source fixed thereon is closely attached to the supporting member 130 of the heat sink 100, the supporting member 130 is in thermal conductive connection with the base 110 of the heat sink, thereby conducting the heat generated by the LED light source to the plurality of pillars 120. The hot air in the space defined by the housing 232 and the support column 120 is rapidly dissipated through the plurality of gaps 126, and the cold air is supplemented later, so that the heat dissipation effect is greatly improved, the temperature of the LED light source is reduced, and the heat dissipation problem of the LED lamp is effectively solved.

Fig. 7 and 8 show an LED lamp 300 according to a second embodiment of the present invention, the LED lamp 300 being a reflective lamp comprising a heat sink 370. The LED lamp 300 further includes a glass plate 310, a reflective cup 320, a heat conductive plate 330, an LED light source 380, a rear cover 340, a lamp cap 350, and a control circuit 360.

Glass sheet 310 is a smooth, light transmitting glass sheet. In some applications, glass sheet 310 may not be provided.

The design of the LED light source 380, the reflective cup 320 and the heat conductive plate 330 can be found in the specification of another chinese patent application No. 200910002486.1 of the present applicant, which is incorporated herein by reference in its entirety.

The rear cover 340, the lamp head 350 and the control circuit 360 can refer to the above description of the first embodiment, and various changes can be made as needed, which are not described in detail herein.

The heat sink 370 of the present embodiment is a modification of the heat sink 100 of the above first embodiment. Specifically, a plurality of spaced apart first legs 372 and a plurality of spaced apart second legs 374 extend from the first and second end faces of the base of the heat sink, respectively. The first leg 372 surrounds and defines a hollow first cavity and the second leg 374 surrounds and defines a hollow second cavity.

As shown, the first post 372 defines a first cavity that is cylindrical for receiving a portion of the rear cover 340 and the control circuit 360 housed within the rear cover 340, as in the embodiments described above. Likewise, the outer surface of the housing of the rear cover 340 is spaced apart from the inner surface of the first support 372 by at least 1mm to facilitate convection of air so that hot air can be more rapidly emitted.

In this embodiment, the second leg 374 is scalloped in longitudinal cross-section, defining a flared second cavity. This is to cooperate with the flared reflector cup 320 such that the reflector cup 320 is fully received within the second cavity. The outer surface of the reflector cup 320 is also spaced from the inner surface of the second leg 374, preferably at least 1 mm. Thereby, a space is defined between the reflector cup 320 and the second support 374, which increases the convection of air and accelerates the emission of hot air.

The heat conductive plate 330, to which the LED light source 380 and the light source panel are fixed, is inserted into the reflective cup through the through-groove at the bottom of the reflective cup 320, and then fixed to the recessed area of the support of the heat sink. In the present embodiment, the heat conductive plate 330 is disposed such that its central vertical axis overlaps with the central vertical axis of the reflector cup 320. This design enables a uniform amount of light and higher illumination brightness to be obtained.

In the embodiment, the LED light source 380 and the light source panel thereof are tightly contacted with the heat conducting plate 330, and the heat conducting plate is connected with the base of the heat sink through the through groove at the bottom of the reflective cup, so that the heat generated by the LED light source during operation is conducted to the first pillar 372 and the second pillar 374 through the base of the light source panel, the heat conducting plate and the heat sink, so that the first pillar 372 and the second pillar 374 generate heat, and the surrounding air becomes hot after the pillars are heated. Since the gaps are formed between the first and second struts 372 and 374, the hot air is diffused through the gaps, and the cold air is then replenished after the hot air is diffused, thereby accelerating the convection of the air. Since the first support 372 and the second support 374 are provided in the present embodiment, the heat dissipation effect is correspondingly increased, and the temperature of the LED light source is further reduced.

Another variation is that the LED fixture further includes two heat sinks 100 as described in the first embodiment, with their bases fixedly connected together and their respective legs facing in opposite directions, wherein one heat sink has a cavity for receiving the rear cover and control circuitry and the other heat sink has a cavity for receiving the reflector cup and the thermally conductive plate.

Therefore, the invention provides a heat dissipation device of a lamp, the cavity of the heat dissipation device is formed by surrounding a plurality of spaced pillars, a large amount of raw materials for preparing a heat dissipation cylinder are omitted, and the heat dissipation device is simple and compact in structure, light in weight and small in size. The LED lamp adopting the heat dissipation device not only greatly enhances the heat dissipation effect and improves the luminous efficiency of the LED light source, but also prolongs the service life and has small volume. The heat sink has a better heat dissipation effect when the inner surface of the post of the heat sink is spaced at least 1mm from the other components of the lamp.

While several preferred embodiments of the present invention have been illustrated in the accompanying drawings, the present invention is not limited to the exact construction and operation as illustrated and described above. Many modifications and variations of the above-described embodiments, which may occur to those skilled in the art through analysis of logic, reasoning or limited experimentation, are within the spirit and scope of the invention and are considered to be within the scope of the invention as claimed.

Claims (19)

1. A heat sink for a luminaire, the heat sink comprising:

a base in heat conductive connection with a heat source; and

a plurality of spaced apart legs extending from the base, the legs surrounding and defining a hollow cavity such that gaps are formed on a side periphery of the cavity.

2. The heat dissipating device of claim 1, wherein said base is annular and has a first end surface, and said plurality of legs extend perpendicularly or obliquely from said first end surface.

3. The heat sink of claim 2, wherein the annular base has a second end face, and a plurality of second legs extend perpendicularly or obliquely from the second end face, the second legs surrounding and defining a second hollow cavity such that a plurality of gaps are formed on a lateral periphery of the second cavity.

4. The heat sink of claim 2, further comprising a support member disposed inside the annular base for carrying a light source and a fixture for securing the light source.

5. The heat sink of claim 4, wherein the support member is bolted, snapped or integrally formed with the inner wall of the annular base.

6. The heat sink of claim 1, wherein the free ends of the legs are slightly bent inwardly or outwardly.

7. An LED lamp comprising at least one LED light source, a base which is insertable into a base socket and connectable to a power supply, a control circuit, a rear cover, and a rear cover which houses said control circuit, wherein said LED lamp further comprises a heat sink according to any one of claims 1 to 6, said LED light source being in thermally conductive contact with a base portion of said heat sink, said rear cover housing said control circuit being at least partially received within a cavity defined by said plurality of posts.

8. The LED light fixture of claim 7 wherein the inner surface of the post is spaced at least 1mm from the outer surface of the back cover.

9. The LED light fixture of claim 7 wherein the heat sink is the heat sink of claim 3, the light fixture further comprising a reflector cup, wherein at least a portion of the back cover housing the control circuitry is received within the cavity defined by the plurality of posts, and wherein at least a portion of the reflector cup is received within a second cavity surrounded and defined by the second post.

10. The LED light fixture of claim 9 wherein the inner surface of the post is spaced at least 1mm from the outer surface of the back cover and the inner surface of the second post is spaced at least 1mm from the outer surface of the reflector cup.

11. The LED light fixture of claim 9 wherein the free end of the second leg is slightly bent inwardly or outwardly so that the free end abuts against the outer surface of the reflector cup.

12. The LED light fixture of claim 7 further comprising a second heat sink of any of claims 1-6 and a reflector cup, wherein the bases of the two heat sinks are fixedly attached together and face in opposite directions, and wherein at least a portion of the reflector cup is received within the cavity of the second heat sink.

13. The LED light fixture of claim 12 wherein the inner surface of the legs of the second heat sink is spaced at least 1mm from the outer surface of the reflector cup.

14. The LED light fixture of claim 7 wherein the heat sink includes a support disposed inside the base, the LED light source being mounted on the support.

15. The LED light fixture of claim 7 wherein the heat sink includes a support disposed within the base, the LED light source being secured to a heat conductor, the heat conductor being mounted to the support.

16. The LED light fixture of any of claims 7-15 wherein the free ends of the legs are slightly bent inward or outward such that the free ends abut against an outer surface of the back cover.

17. The LED light fixture of any of claims 7-15 wherein the heat sink is made of a thermally conductive material and the back cover is made of a non-conductive material.

18. The LED light fixture of claim 17 wherein the thermally conductive material is aluminum, aluminum alloy, ceramic, thermally conductive plastic, or graphite.

19. The LED light fixture of claim 17 wherein the non-conductive material is plastic or glass.