A cooling plate closed cavity brazing device and process in an inert gas protection environment

Abstract

The invention provides a cooling plate closed cavity brazing device and process under an inert gas protection environment. The device structure comprises a drying and preheating furnace, a brazing furnace, a cooling chamber, a chain conveyor and an automatic nitrogen filling and deoxidation mechanism. The drying and preheating furnace and the cooling furnace are arranged at two ends of the brazing furnace. An aluminum heat dissipation cooling plate workpiece to be welded is fixed on the chain conveyor. The chain conveyor passes through the drying and preheating furnace, the brazing furnace and the cooling chamber. Insulation curtains are arranged at the inlets and outlets of the preheating and drying furnace, the brazing furnace and the cooling chamber. The automatic nitrogen filling and deoxidation mechanism is arranged on both sides of the chain conveyor. The nitrogen blowing nozzle of the automatic nitrogen filling and deoxidation mechanism automatically moves with the aluminum heat dissipation cooling plate workpiece and is aligned with the internal cavity of the aluminum heat dissipation cooling plate workpiece. The device and the process of the invention have a high degree of automation, greatly improve the yield rate, and have good promotion value.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, in particular to a cooling plate closed cavity brazing device and process in an inert gas protection environment. Background Art

[0002] The closed cavity of the aluminum heat dissipation cooling plate is a heat exchanger for gas, water or other cooling medium fluid. The aluminum heat dissipation cooling plate has the characteristics of extended surface structure, cooling channel with smaller equivalent diameter and rib surface that is conducive to enhancing convective heat transfer, so that its heat transfer coefficient is higher. As the actuator of the cooling system, the aluminum heat dissipation cooling plate can effectively realize the efficient cooling of power devices, printed circuit board assemblies and electronic chassis. Therefore, the aluminum heat dissipation cooling plate has been widely used in the thermal control technology of electronic equipment. Since the thermal conductivity and specific heat of liquid are greater than those of air, the thermal resistance of each relevant heat exchange link can be greatly reduced and the cooling efficiency can be improved. Therefore, the use of aluminum heat dissipation cooling plate liquid cooling is a better cooling method. Many high-power transmitters use aluminum heat dissipation cooling plates for transmitting tube cooling.

[0003] As the heating power of electronic equipment gradually increases, the flow channels of aluminum heat dissipation cooling plates are also developing towards complexity and miniaturization. The increasing complexity, pressure resistance and harsh environmental requirements of aluminum heat dissipation cooling plates have put forward higher requirements for the subsequent manufacturing of aluminum heat dissipation cooling plates. The narrow channel aluminum heat dissipation cooling plate has dense internal flow channels and is separated by various supporting ribs. In order to improve the heat dissipation efficiency, the cross-sectional area of ​​the flow channels needs to be increased. The increase in the cross-sectional area of ​​the flow channels also compresses the rib width size of the aluminum heat dissipation cooling plate welding, which is only about 1-3mm. Considering the mechanical properties and thermal conductivity, the aluminum heat dissipation cooling plate is designed to use heat-treatable strengthened aluminum alloy. Since aluminum easily forms Al2O3 oxide film when it meets oxygen, the melting point is as high as 2050℃, and even if the surface-treated aluminum alloy is welded quickly, it is inevitable that an oxide film will be generated during the operation. This oxide film will seriously affect the welding quality of the aluminum heat dissipation cooling plate. Therefore, the welding dew point must be strictly controlled, a brazing atmosphere must be provided, and the generation of HF must be minimized. When the aluminum cooling plate workpiece enters the heating furnace for brazing, if the oxygen content in the furnace is too high, the aluminum cooling plate workpiece will be severely oxidized after welding, and the aluminum cooling plate workpiece has a low yield rate. Therefore, the oxygen content in the furnace and the closed cavity of the cooling plate must be controlled. After the aluminum cooling plate workpiece is dried, the atmosphere in the aluminum cooling plate cavity is complex. The oxygen and trace water vapor in the air will affect the welding quality. Therefore, the welding process not only protects the external environment of the cooling plate from oxygen, but also the closed cavity of the aluminum cooling plate must be filled with nitrogen for anti-oxidation protection. At present, there is no good method to effectively solve the problem of high-quality and high-qualified welding of aluminum cooling plates. Summary of the invention

[0004] The purpose of the present invention is to provide a cooling plate closed cavity brazing device and process in an inert gas protection environment.

[0005] The objective of the present invention is achieved in the following manner: a cooling plate closed cavity brazing device and process under an inert gas protection environment, the device structure comprising a drying preheating furnace, a brazing furnace, a cooling chamber, a chain conveyor and an automatic nitrogen filling and deoxidation mechanism, the drying preheating furnace and the cooling furnace are arranged at both ends of the brazing furnace, the aluminum heat dissipation cooling plate workpiece to be welded is fixed on the chain conveyor, the chain conveyor passes through the middle of the drying preheating furnace, the brazing furnace and the cooling chamber, the inlet and outlet of the preheating drying furnace, the brazing furnace and the cooling chamber are provided with heat insulation curtains, the automatic nitrogen filling and deoxidation mechanism is arranged on both sides of the chain conveyor, and the nitrogen blowing nozzle of the automatic nitrogen filling and deoxidation mechanism automatically follows the movement of the aluminum heat dissipation cooling plate workpiece and is aligned with the internal cavity of the aluminum heat dissipation cooling plate workpiece.

[0006] The brazing equipment and process described herein, the automatic nitrogen filling and deoxidation mechanism is composed of a nitrogen main pipe, a lifting air pressure cylinder, a rack and a servo motor. A nitrogen blowing and deoxidation nozzle is arranged on the nitrogen main pipe. The blowing direction of the nitrogen blowing and deoxidation nozzle is opposite to a medium inlet and outlet of an aluminum heat dissipation cooling plate workpiece. The lower part of the nitrogen main pipe is connected to the lifting air pressure cylinder. The bottom of the lifting air pressure cylinder is connected to the rack. A driving gear is arranged at the bottom of the rack. The driving gear is connected to the power output shaft of the servo motor. The servo motor and the control valve of the lifting air cylinder are connected to the single-chip microcomputer controller through a data line.

[0007] The brazing equipment and process are as follows: the brazing furnace is composed of a furnace body and a furnace chamber, the outside of the furnace chamber is a heat-insulating layer, and the inlet and outlet of the furnace chamber are provided with heat-insulating curtains.

[0008] The brazing equipment and process, the brazing process is as follows:

[0009] 1. Preparation process: The front welding process of the aluminum heat dissipation cooling plate workpiece is as follows: evenly apply brazing flux and brazing material on the weld part of the aluminum heat dissipation cooling plate workpiece for later use;

[0010] 2. Drying and preheating process: Place the aluminum heat dissipation cooling plate workpiece in the fixed slot on the chain conveyor, and send it to the drying and preheating furnace for drying by the chain conveyor. The drying time is controlled within 5-8 minutes, and the drying and preheating temperature is controlled at 100-150℃;

[0011] 3. Nitrogen blowing and deoxidation process: the aluminum heat dissipation cooling plate workpiece enters the brazing furnace after passing through the drying preheating furnace, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lowered by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is aimed at the inner cavity of the aluminum heat dissipation cooling plate workpiece from the liquid inlet or outlet of the aluminum heat dissipation cooling plate workpiece to blow nitrogen, and the servo motor drives the rack to drive the nitrogen main pipe from right to left according to the travel speed and direction of the chain conveyor to follow the nitrogen blowing and deoxidation. After deoxidation, the nitrogen and other mixed gases are discharged from the other pipe mouth of the aluminum heat dissipation cooling plate workpiece. After 1-3 minutes of nitrogen blowing and deoxidation, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lifted again by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is lifted upward. The servo motor drives the rack to move right quickly through the gear, and the lifting pneumatic cylinder puts down the nitrogen main pipe again to let the nitrogen blowing and deoxidation nozzle be aimed at the liquid inlet or discharge port inner cavity of the next group of aluminum heat dissipation cooling plate workpieces to follow the nitrogen blowing and deoxidation;

[0012] 4. Brazing process: After nitrogen blowing and deoxidation, the aluminum heat dissipation cooling plate workpiece is sent to the high temperature zone of the brazing furnace by a chain conveyor in an oxygen-free environment. The brazing temperature is controlled at 580-613°C. The brazing material melts and penetrates into the weld of the aluminum heat dissipation cooling plate workpiece. The brazing time is controlled at 2.5 minutes.

[0013] 5. After brazing, the aluminum heat dissipation cooling plate workpiece is slowly sent into the cooling room by the chain conveyor. After cooling to room temperature for 2-5 minutes, it is sent out of the cooling room by the chain conveyor. The robot moves the aluminum heat dissipation cooling plate workpiece up and down from the chain conveyor and sends it to the inspection process and packaging process.

[0014] The beneficial effects of the present invention are: realizing automation and intelligence, greatly reducing the labor intensity of workers, improving production efficiency, and improving the rate of finished products. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the equipment process flow chart;

[0016] Figure 2 It is a schematic diagram of the planar structure of an aluminum heat dissipation cooling plate workpiece;

[0017] Figure 3 It is a left-side structural schematic diagram of the automatic nitrogen filling and deoxygenation mechanism.

[0018] Explanation of the reference numerals: chain conveyor 1, aluminum heat dissipation cooling plate 2, preheating and drying furnace 3, lifting pneumatic cylinder 4, nitrogen blowing and deoxidation nozzle 5, nitrogen main pipe 6, gear 7, rack 8, servo motor 9, brazing furnace chamber 10, thermal insulation layer 11, brazing furnace 12, liquid inlet 13, weld part 14, liquid outlet 15, thermal insulation curtain 16, cooling chamber 17. DETAILED DESCRIPTION

[0019] The following is a detailed description of the brazing equipment and process for the cooling plate enclosed cavity in an inert gas protection environment of the present invention with reference to the accompanying drawings.

[0020] A cooling plate closed cavity brazing equipment and process under an inert gas protection environment, the equipment structure includes a drying and preheating furnace 3, a brazing furnace, a cooling chamber 17, a chain conveyor 1 and an automatic nitrogen filling and deoxidation mechanism, the drying and preheating furnace 3 and the cooling furnace 17 are arranged at both ends of the brazing furnace, the aluminum heat dissipation cooling plate workpiece 2 to be welded is fixed on the chain conveyor 1, the chain conveyor 1 passes through the drying and preheating furnace 3, the brazing furnace and the cooling chamber 17, the inlet and outlet of the preheating and drying furnace 3, the brazing furnace and the cooling chamber 17 are provided with heat insulation curtains 16, the automatic nitrogen filling and deoxidation mechanism is arranged on both sides of the chain conveyor 1, and the nitrogen blowing and deoxidation nozzle 5 of the automatic nitrogen filling and deoxidation mechanism automatically follows the movement of the aluminum heat dissipation cooling plate workpiece 2 and is aligned with the internal cavity of the aluminum heat dissipation cooling plate workpiece 2.

[0021] The brazing equipment and process described herein, the automatic nitrogen filling and deoxidation mechanism is composed of a nitrogen main pipe 6, a lifting air pressure cylinder 4, a rack 8 and a servo motor 9. A nitrogen blowing and deoxidation nozzle 5 is arranged on the nitrogen main pipe 6. The blowing direction of the nitrogen blowing and deoxidation nozzle 5 is opposite to a medium inlet and outlet of the aluminum heat dissipation cooling plate workpiece 2. The lower part of the nitrogen main pipe 6 is connected to the lifting air pressure cylinder 4. The bottom of the lifting air pressure cylinder 4 is connected to the rack 8. A driving gear 7 is arranged at the bottom of the rack 8. The driving gear 7 is connected to the power output shaft of the servo motor 9. The servo motor 9 and the control valve of the lifting cylinder 4 are connected to the single-chip controller through a data line.

[0022] The brazing equipment and process described above include a brazing furnace consisting of a furnace body 12 and a furnace chamber 10 , the outside of the furnace chamber 10 is a heat-insulating layer 11 , and the inlet and outlet of the furnace chamber 10 are provided with heat-insulating curtains 16 .

[0023] Example

[0024] The brazing equipment and process, the brazing process is as follows:

[0025] 1. Preparation process: The front welding process of the aluminum heat dissipation cooling plate workpiece is as follows: evenly apply brazing flux and brazing material on the weld part of the aluminum heat dissipation cooling plate workpiece for later use;

[0026] 2. Drying and preheating process: Place the aluminum heat dissipation cooling plate workpiece in the fixed slot on the chain conveyor, and send it to the drying and preheating furnace for drying by the chain conveyor. The drying time is controlled within 5-8 minutes, and the drying and preheating temperature is controlled at 100-150℃;

[0027] 3. Nitrogen blowing and deoxidation process: the aluminum heat dissipation cooling plate workpiece enters the brazing furnace after passing through the drying preheating furnace, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lowered by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is aimed at the inner cavity of the aluminum heat dissipation cooling plate workpiece from the liquid inlet or outlet of the aluminum heat dissipation cooling plate workpiece to blow nitrogen, and the servo motor drives the rack to drive the nitrogen main pipe from right to left according to the travel speed and direction of the chain conveyor to follow the nitrogen blowing and deoxidation. After deoxidation, the nitrogen and other mixed gases are discharged from the other pipe mouth of the aluminum heat dissipation cooling plate workpiece. After 1-3 minutes of nitrogen blowing and deoxidation, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lifted again by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is lifted upward. The servo motor drives the rack to move right quickly through the gear, and the lifting pneumatic cylinder puts down the nitrogen main pipe again to let the nitrogen blowing and deoxidation nozzle be aimed at the liquid inlet or discharge port inner cavity of the next group of aluminum heat dissipation cooling plate workpieces to follow the nitrogen blowing and deoxidation;

[0028] 4. Brazing process: After nitrogen blowing and deoxidation, the aluminum heat dissipation cooling plate workpiece is sent to the high temperature zone of the brazing furnace by a chain conveyor in an oxygen-free environment. The brazing temperature is controlled at 580-613°C. The brazing material melts and penetrates into the weld of the aluminum heat dissipation cooling plate workpiece. The brazing time is controlled at 2.5 minutes.

[0029] 5. After brazing, the aluminum heat dissipation cooling plate workpiece is slowly sent into the cooling room by the chain conveyor. After cooling to room temperature for 2-5 minutes, it is sent out of the cooling room by the chain conveyor. The robot moves the aluminum heat dissipation cooling plate workpiece up and down from the chain conveyor and sends it to the inspection process and packaging process.

[0030] Except for the technical features described in the specification, all other technical features are known technologies to those skilled in the art.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A cooling plate enclosed cavity brazing device in an inert gas protection environment, characterized in that The equipment structure includes a drying preheating furnace, a brazing furnace, a cooling chamber, a chain conveyor and an automatic nitrogen filling and deoxidation mechanism. The drying preheating furnace and the cooling furnace are arranged at both ends of the brazing furnace. The aluminum heat dissipation cooling plate workpiece to be welded is fixed on the chain conveyor. The chain conveyor passes through the drying preheating furnace, the brazing furnace and the cooling chamber. The inlet and outlet of the preheating drying furnace and the cooling chamber are provided with heat insulation curtains. The automatic nitrogen filling and deoxidation mechanism is arranged on both sides of the chain conveyor. The nitrogen blowing nozzle of the automatic nitrogen filling and deoxidation mechanism automatically moves with the aluminum heat dissipation cooling plate workpiece and is aligned with the internal cavity of the aluminum heat dissipation cooling plate workpiece. The automatic nitrogen filling and deoxidation mechanism is composed of a nitrogen main pipe, a lifting air pressure cylinder, a rack and a servo motor. A nitrogen blowing and deoxidation nozzle is arranged on the nitrogen main pipe. The blowing direction of the nitrogen blowing and deoxidation nozzle is opposite to a medium inlet and outlet of the aluminum heat dissipation cooling plate workpiece. The lower part of the nitrogen main pipe is connected to the lifting air pressure cylinder. The bottom of the lifting air pressure cylinder is connected to the rack. The bottom of the rack is provided with a driving gear. The driving gear is connected to the power output shaft of the servo motor. The servo motor and the control valve of the lifting cylinder are connected to the single-chip controller through a data line. The brazing furnace is composed of a furnace body and a furnace chamber. The outside of the furnace chamber is an insulation layer, and the inlet and outlet of the furnace chamber are provided with heat insulation curtains.

2. A brazing process for a cooling plate closed cavity brazing device in an inert gas protection environment according to claim 1, characterized in that The process steps are as follows:

1. Preparation process: The front welding process of the aluminum heat dissipation cooling plate workpiece is as follows: evenly apply brazing flux and brazing material on the weld part of the aluminum heat dissipation cooling plate workpiece for later use; 2. Drying and preheating process: Place the aluminum heat dissipation cooling plate workpiece in the fixed slot on the chain conveyor, and send it to the drying and preheating furnace for drying by the chain conveyor. The drying time is controlled within 5-8 minutes, and the drying and preheating temperature is controlled within 100-150℃; 3. Nitrogen blowing and deoxidation process: the aluminum heat dissipation cooling plate workpiece enters the brazing furnace after passing through the drying preheating furnace, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lowered by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is aimed at the inner cavity of the aluminum heat dissipation cooling plate workpiece from the liquid inlet or outlet of the aluminum heat dissipation cooling plate workpiece to blow nitrogen, and the servo motor drives the rack to drive the nitrogen main pipe from right to left according to the travel speed and direction of the chain conveyor to follow the nitrogen blowing and deoxidation. After deoxidation, the nitrogen and other mixed gases are discharged from the other pipe mouth of the aluminum heat dissipation cooling plate workpiece. After 1-3 minutes of nitrogen blowing and deoxidation, the nitrogen main pipe of the automatic nitrogen filling and deoxidation mechanism is lifted again by the lifting pneumatic cylinder, and the nitrogen blowing and deoxidation nozzle is lifted upward. The servo motor drives the rack to move right quickly through the gear, and the lifting pneumatic cylinder puts down the nitrogen main pipe again to let the nitrogen blowing and deoxidation nozzle be aimed at the liquid inlet or discharge port inner cavity of the next group of aluminum heat dissipation cooling plate workpieces to follow the nitrogen blowing and deoxidation; 4. Brazing process: After nitrogen blowing and deoxidation, the aluminum heat dissipation cooling plate workpiece is sent to the high temperature zone of the brazing furnace by a chain conveyor in an oxygen-free environment. The brazing temperature is controlled at 580-613°C. The brazing material melts and penetrates into the weld of the aluminum heat dissipation cooling plate workpiece. The brazing time is controlled at 2.5 minutes.

5. After brazing, the aluminum heat dissipation cooling plate workpiece is slowly sent into the cooling room by the chain conveyor. After cooling to room temperature for 2-5 minutes, it is sent out of the cooling room by the chain conveyor. The robot moves the aluminum heat dissipation cooling plate workpiece up and down from the chain conveyor and sends it to the inspection process and packaging process.

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