TWI615579B - LED motor vehicle headlight heat pipe and manufacturing method thereof - Google Patents

Abstract

The invention discloses an LED motor vehicle headlight heat-conducting tube , which includes a tube shell. The tube shell is provided with an evaporation section, an adiabatic section and a condensation section. A first channel cavity is provided in the evaporation section, and a second channel cavity is provided in the thermal insulation section. The condensation section is provided with a condensation chamber, and the first channel cavity, the second channel cavity and the condensation chamber are all vacuum chambers and filled with condensate. The cross-sectional area of the first channel cavity and the cross-sectional area of the second channel cavity are the same. The cross-sectional area is larger than the cross-sectional area of the first channel cavity or the second channel cavity. In another aspect of the present invention, a method for manufacturing a heat pipe for a headlight of an LED motor vehicle is also provided. In the present invention, the hot gas enters the relatively loose condensing cavity from the relatively narrow first channel cavity and the second channel cavity in turn. The larger volume of the condensation cavity slows down the flow rate of the high heat gas, that is, more hot gas stays in the condensation cavity and Heat dissipation can effectively improve heat dissipation efficiency.

Description

LED motor vehicle headlight heat pipe and manufacturing method thereof

The invention relates to the technical field of heat conduction, in particular to an LED motor vehicle headlight heat pipe and a manufacturing method thereof.

Since the invention of the "heat pipe" by G.M. Grver of the Los Alamos National Laboratory in the United States in 1963, the "heat pipe" technology has been gradually introduced as a heat dissipation component for LED headlights in recent years. The manufacturing technology of heat pipes has been mature and widespread. At present, the near and far light types of car headlights are based on reflector cups designed based on the tungsten wire's inner diameter of 2 ~ 3mm tungsten filaments. This special requirement causes all LED lamp heat pipes used in car headlights to be whole. Flat and long copper tubes with a thickness of less than 3mm, and currently the heat transfer tubes of LED automotive headlights on the market are made of flat or T-shaped. Due to the small volume of the flat or T-shaped condensation section, the heat cannot be effectively released. As a result, the lamp beads of the headlights of cars are often above 230 ° C, resulting in very low heat dissipation efficiency.

In order to overcome the shortcomings of the prior art, an object of the present invention is to provide an LED motor vehicle headlight heat pipe and a manufacturing method thereof. Since the first passage cavity is formed in the evaporation section, the second passage cavity is formed in the heat insulation section, and the condensation section is formed. A condensation cavity is formed inside, and the cross-sectional area of the condensation cavity is larger than the cross-sectional area of the first channel cavity or the second channel cavity. The hot gas enters the relatively loose condensation cavity from the relatively narrow first channel cavity and the second channel cavity in turn. The larger condensing chamber slows down the flow rate of the hot gas, making more hot gas stay in the condensing chamber and dissipate heat, which can effectively To improve heat dissipation efficiency. It can solve the problem of very low heat dissipation efficiency of flat or T-shaped heat pipes.

The purpose of the present invention is achieved by the following technical solution: An LED motor vehicle headlight heat-conducting tube includes a tube shell, the tube shell is provided with an evaporation section, an adiabatic section and a condensation section, and a first channel cavity is provided in the evaporation section, and the adiabatic section A second channel cavity is provided, and a condensation cavity is provided in the condensation section. The first channel cavity, the second channel cavity, and the condensation cavity are in fluid communication in sequence, and the first channel cavity, the second channel cavity, and the condensation cavity are all vacuum chambers and filled. For condensate, the cross-sectional area of the first channel cavity is the same as the cross-sectional area of the second channel cavity, and the cross-sectional area of the condensation cavity is larger than the cross-sectional area of the first channel cavity or the second channel cavity.

Preferably, the inner cavity walls of the first channel cavity, the second channel cavity and the condensation cavity are all provided with a capillary core layer.

Preferably, the cross sections of the first channel cavity and the second channel cavity are both rectangular, and the cross section of the condensation cavity is circular, oval, or polygonal.

Preferably, the width of the rectangular cross section is 1.4 mm, the diameter of the circular cross section is greater than 4.50 mm, or the minor axis of the oval cross section is greater than 2.25 mm.

Preferably, the thickness of the shell wall is 0.3 mm-1 mm.

Preferably, the evaporation section, the heat insulation section and the condensation section are integrally formed, or the heat insulation section and the condensation section are fixed together by welding, or the tube shell includes a first sheet structure and a second sheet structure, The first sheet structure and the second sheet structure are fixed together by welding to form an evaporation section, an insulation section and a condensation section.

Preferably, the thickness of the evaporation section and the adiabatic section in the tube shell is 3 mm or less, and the thickness of the condensation section in the tube shell is greater than 4.5 mm.

A manufacturing method of a heat pipe for a headlight of an LED motor vehicle, 1) selecting a first copper pipe, and reducing and sealing the one end of the first copper pipe, wherein the first copper pipe includes an evaporation section, an insulation section and a condensation section, 2) Insert a sintered mandrel made of stainless steel into the first copper tube and fix it so that a gap is formed between the outer surface of the sintered mandrel and the inner wall of the first copper tube. 3) Mix copper powder and industrial salt to obtain powder A. Alternatively, mix copper powder with industrial salt and alumina fiber to obtain powder B. Use vibration machinery to inject powder A or powder B into the gap. 4) Add nitrogen and sinter repeatedly at a temperature of 940 ° C to 960 ° C to make it evaporate. A capillary core layer is formed on the inner cavity wall of the first channel cavity of the segment, the second channel cavity of the adiabatic segment, and the condensation cavity of the condensation segment. 5) Add condensate to the other end of the first copper pipe, and then The cavity, the second channel cavity, and the condensation cavity are vacuum-processed, so that the first channel cavity, the second channel cavity, and the condensation cavity become vacuum chambers, and then the other end of the first copper pipe is sealed.

A method for manufacturing a headlight heat pipe for an LED motor vehicle, 1) selecting a second copper pipe, and reducing the diameter of one end of the second copper pipe, wherein the second copper pipe includes an evaporation section and an insulation section, and 2) selecting a third Copper pipe, the third copper pipe is the condensation section, the other end of the second copper pipe and the third copper pipe are welded together, 3) a sintered core rod made of stainless steel is inserted into the third copper pipe and the second copper pipe in sequence and Fix it so that a gap is formed between the outer surface of the sintered core rod and the inner wall of the third copper pipe and the second copper pipe, 4) mix copper powder and industrial salt to obtain powder C, or, Alumina fibers are mixed to obtain powder D, and powder C or powder D is poured into the gap using a vibration machine. 5) Nitrogen is added, and sintering is repeated at a temperature of 940 ° C to 960 ° C, so that a capillary core layer is formed on the inner cavity wall of the first channel cavity of the evaporation section, the second channel cavity of the thermal insulation section and the condensation cavity of the condensation section. 6) Add condensate to the other end of the third copper tube, and vacuum-process the first channel cavity, the second channel cavity, and the condensation cavity, so that the first channel cavity, the second channel cavity, and the condensation cavity become vacuum chambers, and then Seal the other end of the third copper pipe.

A method for manufacturing a headlamp heat pipe for an LED motor vehicle, 1) selecting a first sheet structure and a second sheet structure obtained by stamping, and 2) matching the corresponding first jig on the upper surface of the first sheet structure and Fix it so that a first gap layer is formed between the upper surface of the first sheet structure and the first jig. Match the corresponding second jig on the upper surface of the second sheet structure and fix it so that the second sheet structure A second void layer is formed between the surface and the second jig. 3) Mix copper powder and industrial salt to obtain powder E, or mix copper powder with industrial salt and alumina fiber to obtain powder F. Powder E or powder F is poured into the first and second void layers. 4) Nitrogen is added and sintering is repeated at a temperature of 940 ° C to 960 ° C, so that the upper surface of the first sheet structure and the upper surface of the second sheet structure. Capillary core layers are all formed. 5) The two sides of the first sheet structure and the two sides of the second sheet structure are welded together, so that the first sheet structure and the second sheet structure include an evaporation section, an insulation section and a condensation section. The fourth copper tube, 6) add the condensate to the fourth copper tube , Then a fourth brass vacuum treatment, a vacuum chamber such that the fourth copper pipe, and then performs a sealing process in the fourth brass.

Compared with the prior art, the beneficial effect of the present invention lies in: There is a first channel cavity, a second channel cavity is formed in the adiabatic section, and a condensation cavity is formed in the condensation section. The first channel cavity, the second channel cavity and the condensation cavity are all vacuum chambers and filled with condensate, and the cross section of the condensation cavity is The area is larger than the cross-sectional area of the first channel cavity or the second channel cavity. During the operation of the headlights of the motor vehicle, the LED lamp bead heat source causes the high-temperature gas to be generated in the evaporation section, and the high-temperature gas sequentially flows from the narrow first channel cavity and the second channel. The channel cavity quickly enters the loose condensing cavity. The larger volume of the condensing cavity slows down the flow rate of the hot gas, that is, more hot gas stays in the condensing cavity, and the external heat dissipation system of the condensation section absorbs the heat of the hot gas, and the hot gas (water (Steam) When cold, the gas phase is converted into the liquid phase. Because the volume of the condensation chamber is larger, the hot gas (water vapor) can be converted from the gas phase to the liquid phase faster in the condensation chamber, that is, the water vapor is converted into a liquid, and then Adhesion into the capillary core layer, and then flowing back from the condensation section along the capillary core layer to the evaporation section, can effectively improve the heat dissipation efficiency. It can solve the problem of very low heat dissipation efficiency of flat or T-shaped heat pipes.

11 ‧‧‧ evaporation section

12 ‧‧‧ adiabatic section

13 ‧‧‧Condensing section

FIG. 1 is a schematic structural diagram of an embodiment of a heat pipe for a headlight of an LED motor vehicle according to the present invention; FIG. 2 is a schematic structural diagram of another embodiment of a heat pipe for a headlight of an LED motor vehicle according to the present invention; FIG. 3 is shown in FIG. 2 The structural schematic diagram of the evaporation section and the adiabatic section in the heat pipe of the headlight of the LED motor vehicle; FIG. 4 is the structural schematic diagram of the condensation section in the heat pipe of the headlight of the LED motor vehicle shown in FIG. 2; Schematic sectional view of the headlight heat pipe.

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

Hereinafter, the present invention will be further described with reference to the accompanying drawings and specific embodiments. Referring to FIGS. 1-5, the present invention relates to a heat pipe for a headlight of an LED motor vehicle, which includes a tube shell, and the tube shell is provided with an evaporation section 11 and an insulation section. 12 和 condensation section 13.

The evaporation section 11 is a flat tubular structure, in which the thickness of the evaporation section 11 in the shell is 3 mm (that is, the distance between the two sides of the outer surface of the shell 11 in the shell is 3 mm), and the evaporation section in the shell is 3 mm. The shell wall thickness of 11 is 0.3 mm.

In this embodiment, the thickness of the evaporation section 11 in the tube shell is 3 mm. In other embodiments, the thickness of the evaporation section 11 in the shell can be changed according to the actual situation. For example, the thickness of the evaporation section 11 in the shell can be 2.4mm, 2.5mm, or 2.8mm. The thickness may be 3 mm or less.

In this embodiment, the thickness of the shell wall of the evaporation section 11 in the tube shell is 0.3 mm. In other embodiments, the thickness of the shell wall of the evaporation section 11 in the tube shell can be changed according to the actual situation. For example, the thickness of the shell wall of the evaporation section 11 in the tube shell can be 0.4 mm, 0.5 mm, or 1 mm. The thickness of the shell wall of the middle evaporation section 11 may be 0.3 mm-1 mm.

The heat insulation section 12 is a flat tubular structure, in which the thickness of the heat insulation section 12 in the shell is 3 mm, that is, the distance between the two sides of the outer surface of the heat insulation section 12 in the shell is 3 mm, and the heat insulation section 12 in the shell is 12 The wall thickness of the shell is 0.3mm.

In this embodiment, the thickness of the heat insulation section 12 in the tube shell is 3 mm. In other implementations In the example, the thickness of the heat insulation section 12 in the shell can be changed according to the actual situation. For example, the thickness of the heat insulation section 12 in the shell can be 2.4mm, 2.5mm, or 2.8mm, as long as the thickness of the heat insulation section 12 in the shell is less than or equal to 3mm is sufficient.

In this embodiment, the thickness of the shell wall of the heat insulation section 12 in the tube shell is 0.3 mm. In other embodiments, the thickness of the shell wall of the heat insulation section 12 in the shell can be changed according to the actual situation. For example, the thickness of the shell wall of the heat insulation section 12 in the shell can be 0.4mm, 0.5mm, or 1mm. The thickness of the shell wall of the middle insulation section 12 may be 0.3 mm-1 mm.

The condensing section 13 is a circular tube structure, in which the thickness of the condensing section 13 in the shell is 8mm, that is, the distance between the two sides of the outer surface of the shell of the condensing section 13 in the shell is 8mm, and the shell of the condensing section 13 in the shell The body wall thickness was 0.3 mm.

In this embodiment, the thickness of the condensation section 13 in the tube shell is 8 mm. In other embodiments, the thickness of the condensation section 13 in the shell can be changed according to the actual situation. For example, the thickness of the condensation section 13 in the shell can be 8.8 mm or 10 mm.

In this embodiment, the thickness of the shell wall of the condensation section 13 in the tube shell is 0.3 mm. In other embodiments, the thickness of the shell wall of the condensation section 13 in the shell can be changed according to the actual situation. For example, the thickness of the shell wall of the condensation section 13 in the shell can be 0.4mm, 0.5mm, or 1mm, as long as the shell is guaranteed The thickness of the middle condensation section 13 may be 0.3 mm-1 mm.

A first channel cavity is formed in the evaporation section 11, a second channel cavity is formed in the thermal insulation section 12, and a condensation cavity is formed in the condensation section 13, wherein the first channel cavity, the second channel cavity and the condensation cavity are in fluid communication in sequence. The cross sections of the first channel cavity and the second channel cavity are rectangular (the cross section of the first channel cavity refers to the cross section of the inner wall of the evaporation section 11 and the cross section of the second channel cavity refers to the cross section of the inner wall of the thermal insulation section 12), The cross section of the condensation chamber is circular or oval (the cross section of the condensation chamber refers to the condensation section 13 Inner wall cross section), the cross-sectional area of the first channel cavity is the same as the cross-sectional area of the second channel cavity, and the cross-sectional area of the condensation cavity is larger than the cross-sectional area of the first channel cavity or the second channel cavity. The width of the rectangular cross section in the first and second channel cavities is 1.4 mm, the diameter of the circular cross section in the condensing cavity is greater than 4.50 mm, or the cross section of the elliptical cross section in the condensing cavity is short. The semi-axis is larger than 2.25mm.

In this embodiment, the cross section of the condensation chamber is circular. In other embodiments, the cross-section of the condensation chamber may be polygonal.

In this embodiment, the width of the rectangular cross sections in the first channel cavity and the second channel cavity is 1.4 mm. In other embodiments, the width of the rectangular cross section can be changed according to the actual situation. For example, the width of the rectangular cross section can be 1.5 mm or 1.6 mm.

The evaporation section 11, the thermal insulation section 12 and the condensation section 13 are integrally formed; or, the evaporation section 11 and the thermal insulation section 12 are integrally formed, and the thermal insulation section 12 and the condensation section 13 are fixed together by welding; and Alternatively, the tube shell includes a first sheet-like structure and a second sheet-like structure, wherein the first sheet-like structure and the second sheet-like structure are both obtained by stamping, and between the first sheet-like structure and the second sheet-like structure They are fixed together by welding to form the evaporation section 11, the heat insulation section 12 and the condensation section 13 (that is, the first channel cavity and the heat insulation section of the evaporation section 11 are formed between the first sheet structure and the second sheet structure. The second channel cavity of 12 and the condensation cavity of the condensation section 13). The length of the shell formed by the evaporation section 11, the thermal insulation section 12 and the condensation section 13 can be designed according to actual conditions.

The first channel cavity, the second channel cavity, and the condensation cavity are all vacuum chambers. The first channel cavity, the second channel cavity, and the condensation cavity are filled with condensate (the condensate is ionized water). A capillary core layer is formed on the inner cavity wall of the two-channel cavity and the condensation cavity. During the working process of the headlight of a motor vehicle, the heat source of the LED lamp beads causes the ionized water in the evaporation section 11 to evaporate, thereby generating a shape. Into hot gas (water vapor), the hot gas (water vapor) from the narrow first channel cavity and the second channel cavity into the loose condensation cavity quickly, the larger volume of the condensation cavity slows down the flow rate of the hot gas, that is, more Much hot gas stays in the condensation chamber, and the external heat dissipation system of the condensing section 13 absorbs the heat of the hot gas. The hot gas (water vapor) converts the gas phase into the liquid phase when it is cold. Due to the larger volume of the condensation chamber, the hot gas ( Water vapor) can be converted from the gas phase to the liquid phase faster in the condensation chamber, that is, the water vapor changes the liquid, and then attaches to the cavity wall of the condensation chamber and enters the capillary core layer, and flows from the condensation section 13 along the capillary core layer back to the evaporation section. In 11, the liquid is converted by water vapor and adheres to the capillary core layer under the capillary force of the capillary core layer, and then flows from the condensation section 13 along the capillary core layer to the evaporation section 11 to effectively improve the heat dissipation efficiency.

In another aspect of the present invention, a method for manufacturing the heat conduction tube of an LED motor vehicle headlight is also provided: 1) selecting a first copper tube, and reducing and sealing the one end of the first copper tube, wherein the first copper The tube includes an evaporation section 11, an insulation section 12, and a condensation section 13. 2) A sintered core rod made of stainless steel is inserted into the first copper tube and fixed, so that the outer surface of the sintered core rod and the inner wall of the first copper tube are formed. Gap, 3) mixing copper powder and industrial salt to obtain powder A, or mixing copper powder and industrial salt with alumina fiber to obtain powder B, using a vibration machine to inject powder A or powder B into the gap, 4 ) Nitrogen is added and sintering is repeated at a temperature of 940 ° C to 960 ° C, so that the inner cavity walls of the first passage cavity of the evaporation section 11, the second passage cavity of the heat insulation section 12, and the condensation cavity of the condensation section 13 are all formed. with capillary core, 5) the condensate is added at the other end of the first copper pipe, and then the first passage chamber, the second chamber and the passage chamber condenser vacuum processing chamber such that the first passage, a second passage and chamber The condensation chamber becomes a vacuum chamber (to further improve the first channel chamber, For the vacuum degree of the two-channel cavity and the condensation chamber, the residual air in the first copper tube must be degassed twice, that is, the evaporation section 11 is heated so that the water vapor squeezes the residual air from one end of the first copper tube to the other end, and then To the outside of the pipe), and then the other end of the first copper pipe is sealed to complete the production of the heat pipe.

In another aspect of the present invention, there is also provided another manufacturing method of the LED motor vehicle headlight heat pipe: 1) selecting a second copper pipe, and reducing the diameter of one end of the second copper pipe, wherein the second The copper tube includes the evaporation section 11 and the thermal insulation section 12, 2) the third copper tube is selected, the third copper tube is the condensation section 13, the other end of the second copper tube is welded with the third copper tube, and 3) is made of stainless steel The sintered core rod is inserted into the third copper tube and the second copper tube in order and fixed, so that a gap is formed between the outer surface of the sintered core rod and the inner wall of the third copper tube and the second copper tube, 4) the copper powder and Mix industrial salt to get powder C, or mix copper powder with industrial salt and alumina fiber to get powder D, use vibration machine to fill powder C or powder D into the gap, 5) add nitrogen, at 940 ℃ ~ The sintering is repeated at a temperature of 960 ° C, so that a capillary core layer is formed on the inner cavity wall of the first channel cavity of the evaporation section 11, the second channel cavity of the thermal insulation section 12, and the condensation cavity of the condensation section 13, Condensate is added to the other end of the third copper tube, and the first channel cavity, the second channel cavity and the cold Chamber vacuum processing chamber such that the first passage, a second passage in a vacuum chamber and the condensation chamber chamber (chamber to further improve a first passage, a second passage chamber and the vacuum degree of the condensation chamber, a second copper tube and shall Residual air in the third copper pipe is degassed twice, that is, the evaporation section 11 is heated so that water vapor squeezes the residual air from the inner end of the second copper pipe to the other end of the third copper pipe, and then to the outside of the pipe), and then The third copper pipe is sealed at the other end to complete the production of the heat pipe.

In another aspect of the present invention, a third manufacturing method of the LED motor vehicle headlight heat pipe is provided: 1) selecting the first sheet structure and the second sheet structure obtained by stamping, and 2) the The upper surface of the first sheet structure matches the corresponding first jig and is fixed, so that a first gap layer is formed between the first surface of the first sheet structure and the first jig, and on the second sheet structure The surface matches the corresponding second jig and is fixed so that a second gap layer is formed between the upper surface of the second sheet structure and the second jig. 3) Mix copper powder and industrial salt to obtain powder E, or, Copper powder is mixed with industrial salt and alumina fiber to obtain powder F, and powder E or powder F is poured into the first void layer and the second void layer using a vibration machine. 4) Nitrogen is added at a temperature of 940 ° C to 960 ° C. Repeated sintering at the temperature, so that a capillary core layer is formed on the upper surface of the first sheet structure and the upper surface of the second sheet structure. 5) Weld the two sides of the first sheet structure and the two sides of the second sheet together. So that the first sheet-like structure and the second sheet-like structure include the evaporation section 11 The fourth copper tube in the thermal insulation section 12 and the condensation section 13; 6) The condensate is added to the fourth copper tube, and the fourth copper tube is vacuum-treated so that the fourth copper tube becomes a vacuum chamber (to further improve the first For the vacuum degree of the channel cavity, the second channel cavity and the condensation cavity, the residual air in the four copper tubes must be degassed twice, that is, the evaporation section 11 is heated so that the water vapor squeezes the residual air from one end of the four copper tubes to the other end. , And then discharged to the outside of the pipe), and then sealing the fourth copper pipe to complete the production of the heat pipe.

When the present invention is used, the first passage cavity is formed in the evaporation section 11, the second passage cavity is formed in the heat insulation section 12, and the condensation cavity is formed in the condensation section 13, wherein the first passage cavity, the second passage cavity, and the condensation cavity are formed. They are in fluid communication in sequence, and the first channel cavity, the second channel cavity, and the condensation cavity are all vacuum chambers. The first channel cavity, the second channel cavity, and the condensation cavity are filled with condensate (the condensate is ionized water). A capillary core layer is formed on the inner cavity wall of the channel cavity, the second channel cavity, and the condensation cavity, and the cross-sectional area of the condensation cavity is larger than the cross-sectional area of the first channel cavity or the second channel cavity. In the LED lamp bead heat source, the ionized water in the evaporation section 11 evaporates, thereby generating the formation of hyperthermic gas (water vapor). The hyperthermic gas (water vapor) sequentially enters the loose condensation from the narrow first channel cavity and the second channel cavity in turn. In the cavity, the larger volume of the condensation chamber slows down the flow rate of the hot gas, that is, more hot gas stays in the condensation chamber, and the external heat dissipation system of the condensation section 13 absorbs the heat of the hot gas. Phase conversion into liquid phase. Because the volume of the condensation chamber is larger, the hot gas (water vapor) can be converted from the gas phase to the liquid phase faster in the condensation chamber, that is, the water vapor is converted into a liquid, and then attached to the capillary core layer. Then, it flows from the condensation section 13 along the capillary layer back to the evaporation section 11, that is, after the water vapor changes the liquid, it is attached to the capillary core layer by the capillary force of the capillary core layer, and then flows from the condensation section 13 along the capillary core layer. The reuse in the re-evaporation section 11 can effectively improve the heat dissipation efficiency. It can solve the problem of very low heat dissipation efficiency of flat or T-shaped heat pipes. In another aspect of the present invention, a method for manufacturing a heat pipe for a headlight of an LED motor vehicle is also provided.

For those skilled in the art, according to the technical solutions and concepts described above, various other corresponding changes and deformations can be made, and all these changes and deformations should fall within the protection scope of the patent application scope of the present invention.

Claims (10)

An LED motor vehicle headlight heat-conducting tube includes a tube shell, the tube shell is provided with an evaporation section, an insulation section, and a condensation section, the evaporation section is provided with a first channel cavity, and the heat insulation section is provided with a second A channel cavity, the condensation section is provided with a condensation cavity, the first channel cavity, the second channel cavity, and the condensation cavity are in fluid communication in sequence, and the first channel cavity, the second channel cavity, and the condensation cavity are all vacuum chambers And filled with condensate, the cross-sectional area of the first channel cavity is the same as the cross-sectional area of the second channel cavity, and the cross-sectional area of the condensation cavity is larger than the cross-sectional area of the first channel cavity or the second channel cavity. According to the LED motor vehicle headlight heat pipe according to claim 1, a capillary core layer is provided on the inner cavity wall of the first channel cavity, the second channel cavity, and the condensation cavity. According to the LED motor vehicle headlight heat pipe according to claim 1, the first channel cavity and the second channel cavity are rectangular in cross section, and the condensation cavity is circular, oval or polygonal in cross section. According to claim 3, the LED motor vehicle headlight heat pipe has a rectangular cross-sectional width of 1.4 mm, a circular cross-section having a diameter greater than 4.50 mm, or an oval shape. The minor semi-axis of the cross section is greater than 2.25mm. According to the LED motor vehicle headlight heat pipe described in claim 1, the thickness of the tube shell wall is 0.3 mm-1 mm. According to the LED motor vehicle headlight heat pipe according to claim 1, the evaporation section, the heat insulation section and the condensation section are integrally formed, or the heat insulation section and the condensation section are fixed together by welding. Alternatively, the tube shell includes a first sheet-like structure and a second sheet-like structure, and the first sheet-like knot The structure and the second sheet structure are fixed together by welding to form the evaporation section, the heat insulation section and the condensation section. According to the LED motor vehicle headlight heat pipe according to any one of claims 1-6, the thickness of the evaporation section and the thermal insulation section in the tube shell is less than or equal to 3 mm, and the thickness of the condensation section in the tube shell is greater than 4.5 mm. . A method for manufacturing a heat pipe for a headlight of an LED motor vehicle is characterized in that: 1) a first copper pipe is selected, and one end of the first copper pipe is reduced in diameter and sealed, wherein the first copper pipe includes an evaporation section, an adiabatic section and condensation 2) Insert the sintered core rod made of stainless steel into the first copper tube and fix it so that a gap is formed between the outer surface of the sintered core rod and the inner wall of the first copper tube, 3) Mix the copper powder and industrial salt Powder A is obtained, or copper powder is mixed with industrial salt and alumina fiber to obtain powder B, and powder A or powder B is poured into the gap using a vibration machine, 4) nitrogen is added at a temperature of 940 ° C to 960 ° C Capillary core layer is formed on the inner cavity wall of the first channel cavity of the evaporation section, the second channel cavity of the adiabatic section and the condensation cavity of the condensation section. 5) Add the other end of the first copper tube The condensate is vacuum-treated on the first channel cavity, the second channel cavity, and the condensation cavity, so that the first channel cavity, the second channel cavity, and the condensation cavity become a vacuum cavity, and then the other end of the first copper pipe is sealed. deal with. A method for manufacturing a heat pipe for a headlight of an LED motor vehicle is characterized in that: 1) selecting a second copper pipe, and reducing and sealing the end of the second copper pipe, wherein the second copper pipe includes an evaporation section and an insulation section; 2) Select the third copper pipe, the third copper pipe is the condensation section, weld the other end of the second copper pipe and the third copper pipe together, 3) insert the sintered core rod made of stainless steel into the third copper pipe and the first The second copper tube is fixed inside, so that a gap is formed between the outer surface of the sintered core rod and the inner wall of the third copper tube and the second copper tube, 4) Mixing copper powder and industrial salt to obtain powder C, or Powder and industrial salt and alumina fiber are mixed to obtain powder D, and powder C or powder D is poured into the gap using a vibration machine, 5) nitrogen is added, and sintering is repeatedly performed at a temperature of 940 ° C to 960 ° C, so that the evaporation A capillary core layer is formed on the inner cavity wall of the first channel cavity of the segment, the second channel cavity of the adiabatic segment, and the condensation cavity of the condensation segment. 6) Add condensate to the other end of the third copper pipe, and then The cavity, the second channel cavity, and the condensation cavity are vacuum-processed, so that the first channel cavity, the second channel cavity, and the condensation cavity become vacuum chambers, and then the other copper tube is sealed at the other end. A manufacturing method of a heat pipe for a headlight of an LED motor vehicle, characterized in that: 1) a first sheet structure and a second sheet structure obtained by stamping are selected, and 2) the upper surface of the first sheet structure is matched correspondingly And fix the first jig such that a first gap layer is formed between the upper surface of the first sheet structure and the first jig, and the corresponding second jig is fixed on the upper surface of the second sheet structure and fixed , So that a second void layer is formed between the upper surface of the second sheet structure and the second jig, 3) mixing copper powder and industrial salt to obtain powder E, or mixing copper powder with industrial salt and alumina fiber Powder F is obtained, and powder E or powder F is poured into the first void layer and the second void layer using a vibration machine, 4) Add nitrogen and sinter repeatedly at a temperature of 940 ° C to 960 ° C, so that a capillary core layer is formed on the upper surface of the first sheet structure and the upper surface of the second sheet structure. 5) Both sides of the first sheet structure It is welded to both sides of the second sheet, so that the first sheet structure and the second sheet form a fourth copper tube including an evaporation section, an insulation section and a condensation section. 6) The condensate is added to the fourth copper tube. Then, the fourth copper pipe is vacuum-processed so that the inside of the fourth copper pipe becomes a vacuum cavity, and then the fourth copper pipe is sealed.