CN114294583A

CN114294583A - Plane heat pipe lamp sheet and lamp thereof

Info

Publication number: CN114294583A
Application number: CN202210037964.8A
Authority: CN
Inventors: 张润锦; 苏涛; 杨池
Original assignee: Shenzhen Agc Lighting Technology Co ltd
Current assignee: Shenzhen Agc Lighting Technology Co ltd
Priority date: 2022-01-13
Filing date: 2022-01-13
Publication date: 2022-04-08

Abstract

The invention belongs to the technical field of lamps and provides a planar heat pipe lamp piece and a lamp thereof. The planar heat pipe lamp piece comprises a lamp bead and two ceramic substrates; the two ceramic substrates are mutually attached, and the opposite surfaces are respectively provided with a micro-groove array; the micro-groove arrays mutually attached to the two ceramic substrates form a cavity, and phase-change liquid is filled in the cavity. The lamp comprises a planar heat pipe lamp piece, a lens frame and a radiator. In the plane heat pipe lamp piece and the lamp provided by the invention, the ceramic flat heat pipe can be directly contacted with the LED light source, so that the contact thermal resistance is reduced. In the lamp provided by the invention, the heat dissipation capability of the heat pipe structure is further enhanced by controlling the detail parameters such as the distance, the height and the like of the heat dissipation fins.

Description

Plane heat pipe lamp sheet and lamp thereof

Technical Field

The invention belongs to the technical field of lamps, and particularly relates to a planar heat pipe lamp piece and a lamp thereof.

Background

An led (light Emitting diode) is a light Emitting diode, which is a solid semiconductor device capable of converting electric energy into visible light, and can directly convert electricity into light. The LED lamp is a lamp with wide application scenes, and has the advantages of less heat productivity, long service life and environmental protection.

The problems of color temperature drift, dominant wavelength shift, luminous flux reduction and the like can be caused by the overhigh LED chip; according to related researches, the service life of the LED is reduced by 5-10% when the temperature of the LED rises by 10 ℃, and the higher the temperature is, the more serious the breakage is; for example, when the LED package temperature reaches 105 ℃ versus 60 ℃, the lifetime is reduced by more than 30%; thus, heat dissipation has hindered the application prospects of the LED industry.

Disclosure of Invention

The invention provides a planar heat pipe lamp piece and a lamp thereof, which are used for optimally designing the whole radiating system of the lamp.

On one hand, the invention provides a planar heat pipe lamp piece, which comprises a lamp bead and two ceramic substrates;

the two ceramic substrates are mutually attached, and the opposite surfaces are respectively provided with a micro-groove array; the positions of the micro-groove arrays of the two ceramic substrates correspond to each other, and the deepest depth of the micro-groove arrays is 0.4 mm; the micro-groove arrays which are mutually attached to the two ceramic substrates form a cavity, and phase change liquid accounting for 40-50% of the total cavity is filled in the cavity;

one of the ceramic substrates is sintered with a copper coating on the surface; the lamp beads are fixed on the copper coating; the surface of the copper coating is coated with a resin insulation layer, and the lamp bead protrudes out of the resin insulation layer.

Specifically, the phase change liquid is ethanol; the ceramic substrate is aluminum nitride ceramic.

In another aspect, the invention provides a lamp using the planar heat pipe lamp sheet.

The lamp comprises a planar heat pipe lamp piece, a lens frame and a radiator;

the planar heat pipe lamp sheet is attached to the surface of one side of the radiator, and the surface of the other side of the radiator is provided with a radiating fin; the lens frame covers one side of the plane heat pipe lamp piece, which is provided with the plane heat pipe lamp piece; the number of the lenses on the lens frame is matched with the number of the lamp beads on the plane heat pipe lamp piece; the lens frame is arranged on the upper surface of the lens frame;

the bottom surface of a radiating fin on the radiator is 1-6mm thick; the thickness of the radiating fin is 0.5-3 mm; the distance between the radiating fins is 5-10 mm; the height of the radiating fins is 20-40 mm;

the planar heat pipe lamp piece comprises a lamp bead and two ceramic substrates;

the two ceramic substrates are mutually attached, and the opposite surfaces are respectively provided with a micro-groove array; the positions of the micro-groove arrays of the two ceramic substrates correspond to each other, and the deepest depth of the micro-groove arrays is 0.4 mm; the micro-groove arrays which are mutually attached to the two ceramic substrates form a cavity, and phase-change liquid is filled in the cavity; one of the ceramic substrates is sintered with a copper coating on the surface; the lamp beads are fixed on the copper coating.

Specifically, the thickness of the bottom surface of a radiating fin on the radiator is 1-4 mm; the thickness of the radiating fin is 1.5-2 mm; the distance between the radiating fins is 5-7 mm; the height of the radiating fin is 20-35 mm.

Specifically, the lamp group bracket comprises a bracket component and a lamp group component; the radiator component consists of a plane heat pipe lamp piece, a lens frame and a radiator;

the lamp group assembly consists of a pair of side plates, at least two radiator assemblies and a light shield; the side surfaces of all the heat dissipation assemblies are clamped by the pair of side plates; the light shield is arranged at the top end of the uppermost radiator and is fixedly connected with the side plate;

the tail ends of two sides of a lamp bracket of the bracket component are provided with through holes; the lamp screw, the crown gear base, the side plate, the reinforcing bracket and the crown gear screw are sequentially arranged in the through hole at the tail ends of the two sides of the lamp bracket from the outer side to the inner side; the through holes at the tail ends of the two sides of the lamp bracket are positioned between the crown gear and the crown gear base; the lamp screw, the crown gear base, the side plate, the reinforcing support and the crown gear screw are all located on the same axis, so that the angle between the support component and the lamp group component is changed.

Further concretely, the power supply box assembly is further included;

a pair of power box brackets which extend outwards and are opposite to the two sides of the lamp bracket are fixed in the middle of the lamp bracket; the power supply box assembly is fixed on the power supply box bracket.

Specifically, waterproof rubber rings are clamped at the edges of the lens frame and the radiator.

Specifically, a cable head and a respirator are arranged on the radiator; the breather is communicated with the cavity formed by the lens frame and the radiator on the plane heat pipe lamp piece.

Specifically, a washer is arranged between the lamp screw and the crown gear.

The invention has the beneficial effects that:

in the plane heat pipe lamp piece provided by the invention, the ceramic flat heat pipe can be directly contacted with the LED light source, so that the contact thermal resistance is reduced. In the lamp provided by the invention, the heat dissipation capability of the heat pipe structure is further enhanced by controlling the detail parameters such as the distance, the height and the like of the heat dissipation fins.

Drawings

FIG. 1 is a schematic diagram of the exploded structure of a flat heat pipe according to the present invention;

FIG. 2 is a schematic cross-sectional view of a flat heat pipe according to the present invention;

FIG. 3 is a schematic diagram of different levels of the flat heat pipe according to the present invention;

FIG. 4 is a schematic view of the complete appearance of the flat heat pipe according to the present invention;

FIG. 5 is a schematic view of the exploded heat sink assembly of the present invention;

FIG. 6 is a schematic view of a heat sink assembly according to the present invention;

fig. 7 is a schematic view of the exploded structure of the lamp body assembly of the present invention;

FIG. 8 is a schematic view of the entire appearance of the lamp body assembly of the present invention;

FIG. 9 is a schematic view of a bracket assembly of the present invention shown in an exploded configuration;

FIG. 10 is a schematic view of a bracket assembly of the present invention shown in an exploded configuration;

FIG. 11 is a schematic view of a bracket assembly of the present invention shown in an exploded configuration;

FIG. 12 is a schematic view of a bracket assembly according to the present invention;

FIGS. 13a and 13b are experimental results of the thickness of the bottom surface of the heat sink of the present invention;

FIGS. 14a and 14b are experimental results of the thickness of the heat dissipating fins of the present invention;

15a, 15b is the heat dissipation fin spacing experimental results of the present invention;

fig. 16a and 16b show the height test results of the heat dissipation fins of the present invention.

In the figure: 1. a lamp bead; 2. a copper cladding layer; 3. a ceramic substrate; 4. a ceramic substrate; 7. a resin insulating layer; 17. a lens screw; 18. a lens frame; 19. a waterproof rubber ring; 20. a lamp panel screw; 22. a heat sink; 23. a respirator; 24. a cable head; 25. a radiator screw hole; 26. a screw hole; 27. a radiator screw hole; 28. a screw hole; 29. a radiator screw hole; 30. a side plate; 31. a heat sink screw; 32. a light shield; 33. a lens hood screw; 34. a crown screw; 35. a reinforcing bracket; 36. a crown gear base; 37. a lamp bracket; 38. crown gear; 39. a lamp screw; 40. a power pack bracket screw; 41. a power pack bracket screw; 42. a power supply box support; 43. a power box screw; 44. a power box assembly; 100. a planar heat pipe; 200. a heat sink assembly; 300. a lamp group assembly; 400. a bracket assembly.

Detailed Description

In order to make the technical problems solved, technical solutions adopted, and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention are described in further detail below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The structure of the embodiment is shown in figures 1-4; the lamp bead is composed of a lamp bead 1, a copper coating layer 2, a ceramic substrate 3 and a ceramic substrate 4; the lamp beads 1 are LED lamp beads and are welded on the copper coating layer 2 in an array mode; as shown in fig. 1, the copper cladding layer 2 is a thin sheet structure with a flat surface and no gaps, and the copper cladding layer 2 is sintered on the upper surface of the ceramic substrate 3 in order to fit the ceramic substrate 3 as much as possible and reduce gaps. And the other surface of the copper coating layer 2, on which the lamp beads 1 are welded, is covered with a resin insulating layer 7 except for the positions of the lamp beads 1. )

A continuous micro groove array is processed on one surface of each of the

ceramic substrates

3 and 4, as shown in fig. 2, and a laser processing method is generally used; the deepest part of each micro groove is 0.4 +/-0.02 mm and is triangular sawtooth-shaped. The groove processing of the ceramic substrate 3 and the groove processing of the ceramic substrate 4 are enabled to be relatively attached in a micro array mode, a cavity is formed between the ceramic substrate 3 and the groove processing of the ceramic substrate 4, pure ethanol with the total volume of 40-50% of the cavity is filled in the cavity, the ethanol is used as phase change liquid for heat conduction in the gap, and the edges of the ceramic substrate 3 and the ceramic substrate 4 are sealed through laser welding.

The surfaces of the copper coating layer 2, the ceramic substrate 3 and the ceramic substrate 4 are all provided with a plurality of through holes, and the through holes are used for fixedly installing and connecting other equipment; the surface through-holes of the copper clad layer 2, the ceramic substrate 3 and the ceramic substrate 4 correspond to each other in position. The assembled planar heat pipe 100 is shown in fig. 4.

The invention adopts the thick film process to directly coat copper on the surface of the material for sintering wiring, can reduce the multilayer thermal resistance from the LED light source to the substrate, and leads the heat to be rapidly conducted to the ceramic substrate 3 and the ceramic substrate 4.

The phase change liquid in the micro-groove array is clamped by the ceramic substrate 3 and the ceramic substrate 4 to be heated and evaporated, the steam moves to the outer ring low-temperature position and is re-condensed into liquid, and then the liquid is transported to the LED heating position through the capillary force generated by the micro-reflux groove on the inner surface; because the integral structure of the invention is thinner and the sintered wick is difficult to effectively fill, the project adopts a double-sided groove type wick structure and a triangular groove shape, and the sharp-angled structure can enhance the action of capillary force, improve the reflux speed of the phase change liquid and prevent the dry burning phenomenon. Aluminum nitride with good heat conduction performance and mechanical performance is preferably used as the materials of the ceramic substrate 3 and the ceramic substrate 4, and because the ceramic insulating performance is good, copper sheets can be directly distributed on the surfaces of the materials through a film thickness method; the LED light source is welded on the surface of the substrate through reflow soldering, so that the multilayer thermal resistance is reduced, and the thermal and electrical separation is realized. The inside was evacuated and filled with ethanol as a phase change liquid, and then sealed by laser welding. Because the existence of non-condensable gas can cause the influence to the heat pipe performance, consequently pass through laser welding technology with the heat pipe and seal one end, the hole is reserved with the inside evacuation of heat pipe in the other end back, pours a certain amount of phase transition liquid, and is sealed with laser welding after accomplishing.

Example 2

A heat sink assembly 200 comprising a light emitting assembly; the solar heat collector consists of a lens screw 17, a lens frame 18, a waterproof rubber ring 19, a lamp panel screw 20, a planar heat pipe 100, a radiator 22, a respirator 23 and a cable head 24, and is shown in figure 6 after assembly, and is shown in figure 5 in an exploded view.

The lens frame 18 of the present embodiment has an array of a plurality of small lenses, and the positions of the small lenses on the lens frame 18 correspond to the positions of the lamp beads 1 on the planar heat pipe 100.

The lens frame 18 is mounted on the heat sink 22, and specifically, the lens frame 18 is provided with a plurality of through holes, and each through hole corresponds to one lens screw 17; a plurality of screw holes 26 are also provided at corresponding positions of the heat sink 22, and the lens screws 17 are fixed in the screw holes 26 of the heat sink 22 through the through holes of the lens frame 18.

A flat heat pipe 100 is sandwiched between the lens frame 18 and the heat sink 22; more specifically, two planar heat pipes 100 are sandwiched within each heat sink assembly 200; the area of each planar heat pipe 100 is less than half of the area of the surface of the heat sink 22 facing the face of the planar heat pipe 100. A plurality of through holes are formed in the planar heat pipe 100 and used for mounting lamp panel screws 20; the lamp panel screw 20 is fixed in the heat dissipation screw hole 25 of the heat sink 22 through the through hole of the planar heat pipe 100 by interference fit.

A waterproof rubber ring 19 is clamped between the lens frame 18 and the radiator 22, and the planar heat pipe 100 is fixed in a cavity formed by the lens frame 18, the radiator 22 and the waterproof rubber ring 19, so that waterproof treatment is performed on the planar heat pipe 100 to the maximum extent; and the cavity formed may be such that in case of ethanol leakage within the planar heat pipe 100, it is controlled within a certain area to prevent diffusion from further damaging other components.

The heat sink 22 has a lens frame 18 mounted on one surface thereof and a plurality of heat dissipating fins disposed on the opposite surface thereof. The height, spacing, and thickness of the heat dissipating fins have a non-linearly dependent effect on heat dissipation.

A radiator screw hole 30 for installing the cable head 24 is arranged on the side surface of the radiator 22; a radiator screw hole 27 for mounting the respirator 23; and screw holes 28 for fixing the lamp set assembly 300 to each other.

Example 3

A lamp assembly 300 is composed of side panels 30, a heat sink assembly 200 and a light shield 32, as shown in FIG. 7, and as shown in FIG. 8 after assembly. The present embodiment comprises four heat sink assemblies 200, two symmetrically arranged side plates 30 and a light shield 32; the four heat sink assemblies 200 are clamped by the side plates 30 on two sides respectively in a stepped arrangement manner, specifically, the side plates 30 are fixed on the screw holes 28 of the heat sink assemblies 200 through side plate screws 31 to realize fixed connection; the hood 32 is disposed on the top end of the uppermost heat sink assembly 200 and is fixed to the side plate 30 by a hood screw 33. A large through hole is arranged in the middle of the side plate 30, and a circle of small through holes is arranged around the through hole; two sides of the larger through hole are respectively provided with a strip-shaped through hole, and the through holes are used for being connected with other elements.

Example 4

A light fixture is composed of a bracket assembly 400, a light set assembly 300 and a power box assembly 44, as shown in FIG. 12. The structure of the bracket assembly 400 is shown in fig. 9-11. The lamp bracket 37 is of a concave structure, and the tail ends of the two ends of the lamp bracket are provided with a plurality of through holes; from outside to inside, a lamp screw 39, a small washer, a large washer, a crown gear 38, a through hole of a lamp bracket 37, a crown gear base 36, a side plate 30, a reinforcing bracket 35 and a ring of crown gear screws 34 are sequentially arranged. The lamp screw 39, the small washer, the large washer, the crown gear 38, the through hole of the lamp bracket 37, the crown gear base 36, the side plate 30, the reinforcing bracket 35 and the crown gear screw 34 are all positioned on the same axis; this set of parts enables controlled, articulated/non-articulated angular adjustment between the bracket assembly 400 and the lamp cluster assembly 300.

A middle cross-post in the concave configuration of the light fixture mount 37; a pair of symmetrical, outward power pack brackets 42 are fixed; the power box bracket 42 is fixedly connected with the lamp bracket 37 through a power box bracket screw 40 and a power box bracket screw 41; the power box bracket screw 40 and the power box bracket screw 41 have the same size and shape, but are oppositely positioned, as shown in fig. 10.

As shown in fig. 11, a power box assembly 44 is disposed on the upper surface of the pair of power box brackets 42, the power box assembly 44 provides power for the whole device, and a plurality of cable heads 24 are disposed on the power box assembly 44 for electrically connecting with the cable heads 24 on the heat sink assembly 200 through cables. The power box assembly 44 is fixed to the power box bracket 42 by passing through the power box bracket 42 by a plurality of power box screws 43. After assembly as shown in fig. 12.

In the experiment, it is found that the heat dissipation performance and the quality of the heat sink assembly 200 do not increase in equal proportion, the proportion of the heat transfer area to the natural convection, the natural convection and the convection block are one of the important factors influencing the heat transfer and dissipation; therefore, the shape and the structure of the fin radiator are optimized, the heat radiation performance can be enhanced, and the cost is saved; the heat dissipation effect of the high-power LED heat radiator is influenced by various factors, including the bottom surface thickness of the heat radiator, the height of the heat dissipation fins and the thickness of the heat dissipation fins; in order to quickly know the influence of the above factors on the heat dissipation performance, the following experiment is performed;

radiator bottom surface thickness experiment:

firstly, under the condition of not changing other conditions, comparing the temperature rise value of the bottom surface of the radiator under the thickness of 1-6mm, finding that the temperature drop rate is maximum when the thickness is changed from 1mm to 2mm, all temperature parameters are the lowest value when the thickness is 3mm, and the temperature of the LED light source is increased along with the increase of the thickness of the bottom surface from 3mm to 6mm, so that the result shows that the thickness of the bottom surface has direct influence on heat conduction, and because the heat conduction capability is related to the sectional area, when the thickness is thinner, the heat flow density generated by high power exceeds the heat conduction capability of the material, and heat flow accumulation is caused; when the thickness is thick, the thermal conductivity of the material is less than the heat dissipation capacity, also resulting in heat flux build-up.

When the thickness of the radiator is more than 4mm, the influence of the increased thickness on heat transfer is smaller and smaller, and the problems of heat transfer, strength, cost and the like are comprehensively considered, so that the thickness of 3mm is the optimal choice.

The experimental conditions were: heat sink size 100 x 43mm, simulated heat source 50W, ambient temperature 298K. The results are shown in FIGS. 13a and 13 b.

Thickness experiment of the radiating fins:

under the condition of not changing other conditions, comparing the influence of the thickness of the radiating fins between 0.5 and 3mm on the radiating performance, finding that the temperature of 0.5mm is higher than that of 1mm, the temperature parameters of all aspects are the lowest when the temperature is 1mm, and gradually increase along with the thickening of the blades, and because the parameters of all aspects are unchanged during comparison and comprise the overall dimension, the thicker the radiating fins are, the smaller the spacing is, and the worse the convection is; however, when the thickness of the blade is less than a certain thickness, the heat conduction capability is affected, so that the heat conduction capability is less than the heat dissipation capability, and heat flow is accumulated.

Under the condition that the thickness of the radiating fins can ensure normal heat transfer, the influence is gradually reduced along with the increase of the thickness, and the problems of heat transfer, strength, cost and the like are comprehensively considered, so that the thickness of 1.5-2mm is the optimal choice.

The experimental conditions were: heat sink size 100 x 43mm, simulated heat source 50W, ambient temperature 298K. The results are shown in fig. 14a and 14 b.

The heat dissipation fin spacing experiment:

under the condition of not changing other conditions, compared with the influence of the distance between the radiating fins and the radiating performance of 5-10mm, the temperature is continuously reduced when the distance is 5-7mm, when the distance is 7-10mm, all temperature parameters are increased, and according to result analysis, when the distance between the radiating fins is increased, the natural convection is facilitated to be formed and the radiating capacity is enhanced, and when the distance is too large, the radiating area is reduced, and the radiating capacity is reduced.

When the thickness is 7mm, the optimal balance point of the heat dissipation area and the convection is set; when the interval is larger than 7mm, although convection becomes good, the heat dissipation area is insufficient, and the temperature gradually rises.

The experimental conditions were: heat sink size 100 x 43mm, simulated heat source 50W, ambient temperature 298K. The results are shown in fig. 15a and 15 b.

Height test of the radiating fins:

under the condition of not changing other conditions, compared with the influence of the height of the radiating fins from 20 mm to 40mm on the radiating performance, the temperature is continuously reduced when the height is from 20 mm to 35mm, and slightly rises when the height is from 35mm to 40mm, according to result analysis, the radiating capacity is reduced when the radiating area is insufficient, and the radiating fins are higher than a certain height, so that although the radiating area is increased, the natural convection is reduced, and the radiating capacity is reduced on the contrary. When the height of the radiating fin reaches 35mm, the influence of increasing the height on heat radiation is smaller and smaller, and the problems of heat radiation performance, cost and the like are comprehensively considered, so that the height of 35mm is the optimal choice.

The experimental conditions were: heat sink size 100 x 43mm, simulated heat source 50W, ambient temperature 298K. The results are shown in FIGS. 16a and 16 b.

In the description herein, it is to be understood that the terms "upper," "lower," "left," "right," and the like are used in an orientation or positional relationship merely for convenience in description and simplicity of operation, and do not indicate or imply that the referenced device or element must have a particular orientation, configuration, and operation in a particular orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the terms "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be appropriately combined to form other embodiments as will be appreciated by those skilled in the art.

The technical principle of the present invention is described above in connection with specific embodiments. The description is made for the purpose of illustrating the principles of the invention and should not be construed in any way as limiting the scope of the invention. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.

Claims

1. The planar heat pipe lamp piece is characterized by comprising a lamp bead and two ceramic substrates;

2. The planar heat pipe lamp plate as claimed in claim 1, wherein the phase change liquid is ethanol; the ceramic substrate is aluminum nitride ceramic.

3. The lamp is characterized by comprising a planar heat pipe lamp piece, a lens frame and a radiator;

4. A light fixture as recited in claim 3, wherein the bottom surface of the fins on the heat sink is between 1-4mm thick; the thickness of the radiating fin is 1.5-2 mm; the distance between the radiating fins is 5-7 mm; the height of the radiating fin is 20-35 mm.

5. The light fixture of claim 3, comprising a bracket assembly, a lamp group assembly; the radiator component consists of a plane heat pipe lamp piece, a lens frame and a radiator;

6. The light fixture of claim 5, further comprising a power box assembly;

7. A light fixture as recited in claim 3, wherein a waterproof rubber ring is sandwiched between the lens frame and the edge of the heat sink.

8. A light fixture as recited in claim 3, wherein the heat sink has a cable head and a breather disposed thereon; the breather is communicated with the cavity formed by the lens frame and the radiator on the plane heat pipe lamp piece.

9. A lamp as set forth in claim 3, characterized in that a washer is provided between the lamp screw and the crown gear.