Contact type aging cooling device and cooling method for high-power laser

Abstract

The invention relates to a high-power laser contact type aging cooling device and cooling method, and belongs to the technical field of semiconductor laser aging. The cooling device comprises a cooler, a water cooling machine, a water tank and a circulating pump, the cooler is connected with the water cooling machine through a first circulating pipeline, a second circulating pipeline is further arranged on the cooler, and the circulating pump and the water tank are arranged on the second circulating pipeline. The bottom of the laser is in direct contact with cooling water, so that heat generated by the laser is quickly dissipated, high-pressure cooling water and low-pressure cooling water are separated, and the influence of the high-pressure water on the laser is avoided.

Description

Technical Field

[0001] The invention relates to a high-power laser contact-type aging cooling device and a cooling method, belonging to the technical field of semiconductor laser aging. Background Art

[0002] Semiconductor lasers, also known as diode lasers, are high-power semiconductor lasers. They offer advantages such as small size, light weight, high electro-optical conversion efficiency, high reliability, and long service life. Furthermore, their electric drive facilitates their use on various platforms. Consequently, high-power semiconductor lasers have broadened their applications, including in laser processing, laser communications, medical and cosmetic procedures, scientific research, military defense, and laser entertainment displays. Many applications require semiconductor lasers to possess long life, high stability, high reliability, and extended storage time.

[0003] The power of semiconductor lasers on the market is getting higher and higher, reaching more than ten kilowatts. During the aging test of semiconductor lasers, the need for heat dissipation also increases. The existing cooling method generally uses aluminum / copper water-cooling plates for cooling and aging, or directly couples the laser to the water-cooling plate for cooling and aging. The aluminum / copper water-cooling plate has a good cooling effect for the aging of low-power lasers, but is not ideal for the heat dissipation of high-power lasers. Directly coupling the laser to the water-cooling plate for cooling and aging has high process requirements and is difficult to produce. Therefore, the existing aging method has limitations for the aging heat dissipation and production of high-power lasers.

[0004] Chinese patent document CN117269719A discloses a high-current COS chip aging tool and its use method. The tool includes a water-cooling plate, a relay plate, an insulating block, an electrode spring, a chip retaining plate, a column, an upper crossbeam, a lower crossbeam, and an insulating plate. The water-cooling plate is provided with a relay plate, an insulating plate on one side of the relay plate, and a chip retaining plate on the other side. The relay plate is provided with columns at both ends. The upper crossbeam is fixedly provided at the top of the column, and a lower crossbeam is slidingly provided in the middle of the column. Several insulating blocks are arranged side by side on the lower crossbeam. Two spring pins are provided in the insulating block. Below the spring pins are an electrode spring fixed to the insulating plate. The electrode spring is connected to a power cord. This tool uses a conventional water-cooling plate for aging, which cannot meet the heat dissipation requirements of high-power lasers.

[0005] Chinese patent document CN112490842A discloses a temperature control system for pump laser aging, comprising: a water chiller; at least two water cooling plates, each for attaching a pump laser to it for aging testing, the first water inlet of each water cooling plate connected to the second water outlet of the water chiller, and the first water outlet of each water cooling plate connected to the second water inlet of the water chiller; a temperature monitoring device for real-time monitoring of at least the temperature of each pump laser; and at least two temperature adjustment structures, each connected between the first water inlet of each water cooling plate and the second water outlet of the water chiller, and used to adjust the water inlet temperature of each water cooling plate based on the temperature monitoring results of the temperature monitoring device. This system primarily achieves temperature control to meet different aging temperature requirements, but the water cooling design still uses conventional water cooling plates, which does not significantly improve heat dissipation capacity.

[0006] The above-mentioned laser aging cooling adopts water-cooled plate bonding heat dissipation technology, which has contact thermal resistance between the heat dissipation surface and the water-cooled plate. It is difficult to improve the heat transfer performance and cannot meet the needs of rapid heat dissipation of large amounts of heat generated during high-temperature aging of high-power lasers. Summary of the Invention

[0007] Aiming at the problem that the heat generated by high-power lasers during high-temperature aging in the prior art is slowly dissipated, the present invention provides a high-power laser contact-type aging cooling device.

[0008] The present invention also provides a cooling method for the high-power laser contact-type aging cooling device.

[0009] Explanation of terms:

[0010] Water chiller: A cooling water device used to provide constant temperature, constant flow and constant pressure, also known as a chiller. It is a cooling water device that can provide constant temperature, constant flow and constant pressure. Water chillers are divided into air-cooled chillers and water-cooled chillers.

[0011] Ball valve: A ball valve is a valve whose opening and closing member (ball) is driven by a valve stem and rotates around its axis. It can also be used for regulating and controlling fluids. The hard-sealed V-shaped ball valve has a strong shear force between its V-shaped ball core and the metal valve seat welded with cemented carbide, making it particularly suitable for media containing fibers and tiny solid particles. Multi-way ball valves can not only flexibly control the confluence, diversion, and flow direction of media in pipelines, but can also close any channel and connect the other two channels. This type of valve should generally be installed horizontally in the pipeline.

[0012] Circulation pump: A pump used to transport circulating fluid for reaction, absorption, separation, and absorption fluid regeneration within the system. A single-stage centrifugal pump is typically used. The flow rate of a circulation pump is medium, and under stable operating conditions, the pump's flow rate varies minimally. Its head is low and is only used to overcome pressure drops in the circulation system. A low-head pump can be used.

[0013] The technical solutions of the present invention are as follows:

[0014] A high-power laser contact aging cooling device comprises a cooler, a first heat exchange circulation pipeline, and a second heat exchange circulation pipeline, wherein the cooler comprises a cavity and a laser heat dissipation surface contact port connected to the cavity;

[0015] The second heat exchange circulation pipeline includes a circulation pump and a water tank to provide cooling medium for the cavity;

[0016] The first heat exchange circulation pipeline includes a copper tube and a water cooler, wherein the copper tube is bent or wrapped around and arranged in the cooler cavity to form a heat transfer body to provide heat exchange cooling for the cooling medium in the cavity.

[0017] The heat of the cooling medium inside the cavity diffuses to the copper tube and is carried to the water cooler through the high-pressure circulation loop formed by the water cooler and the copper tube for dissipation. The heat of the laser is mainly dissipated through the chiller, and the high pressure inside the high-pressure circulation loop has no effect on the laser.

[0018] According to the preferred embodiment of the present invention, the cooling medium is at least one of deionized water, Freon, liquid ammonia and liquid nitrogen.

[0019] According to a preferred embodiment of the present invention, two sets of copper tubes are provided, each with its own water inlet and outlet, connected to a water chiller. Furthermore, the two sets of copper tubes are arranged side by side. The copper tubes have excellent thermal conductivity and are evenly distributed within the cavity, allowing them to more quickly remove heat from the cavity, avoiding the problem of high temperatures near the water outlet associated with using a single set of long copper tubes.

[0020] Preferably, according to the present invention, a first circulating water inlet and a first circulating water outlet are provided on one side of the cavity, and the first circulating water inlet and the first circulating water outlet are used to connect the copper pipe and the chiller. A second circulating water inlet and a second circulating water outlet are also provided on the cavity, and the second circulating water inlet is used to connect the cavity and the water tank, and the second circulating water outlet is used to connect the circulating pump and the cavity.

[0021] Preferably, according to the present invention, the second circulating water inlet and the second circulating water outlet are arranged at the upper part of the cavity, which is conducive to the discharge of internal bubbles. The bubbles enter the water tank through the circulating pump and overflow from the water tank.

[0022] Preferably, according to the present invention, at least one contact port is provided. By providing multiple contact ports, simultaneous aging of multiple lasers can be achieved. The bottom of the laser is in direct contact with the liquid in the cavity, which is beneficial for a large amount of heat from the laser to quickly diffuse into the liquid. The liquid pressure is low, and the impact on the laser housing is small.

[0023] Preferably, according to the present invention, a gasket is provided on the contact port of the cavity, and the laser is fixed to the contact port by screws. The gasket plays a sealing role between the components. Since the lasers are different, the fixing hole positions are also different. The contact port can be opened according to actual conditions, and the size of the gasket is determined according to the laser.

[0024] Preferably according to the present invention, a ball valve A is provided on the pipeline between the circulation pump and the second circulation water outlet, and a ball valve B is provided on the pipeline between the water tank and the second circulation water outlet.

[0025] Preferably according to the present invention, the water inlet end of the circulation pump is connected to the cavity, and the water outlet end is connected to the water tank.

[0026] The second heat exchange circulation pipeline and the cavity form a low-pressure circulation loop, and the water cooler and copper pipe form a high-pressure circulation loop. The water outlet of the water cooler is high-pressure water with a pressure of about 0.3MPa. For precision lasers, it is a high pressure and will have a slight effect on the optical path. The connection method of the circulation pump is the opposite. The water inlet end is connected to the cavity, which is equivalent to sucking the water in the water tank into the circulation pump. This pressure is small and can be ignored. The water outlet end of the circulation pump is connected to the water tank, and the water outlet will have a certain pressure, which is released in the water tank.

[0027] The cooling method of the high-power laser contact aging cooling device comprises the following steps:

[0028] (1) Install the laser on the cavity contact port, connect the copper pipe to the water cooler, connect the water inlet of the circulation pump to the cavity, and connect the water outlet to the water tank;

[0029] (2) The circulation pump and water cooler are started, the cavity is filled with cooling medium, and the cooling medium contacts the bottom of the laser;

[0030] (3) The laser undergoes aging test. The heat generated by the laser diffuses directly into the cooling medium in the cavity. The heat is dissipated into the water cooler through the high-pressure circulation loop formed by the water cooler and the copper tube. The high pressure inside the high-pressure circulation loop has no effect on the laser. The circulation pump drives the cooling medium in the cavity to flow, and simultaneously takes out part of the heat emitted by the laser. The first heat exchange circulation pipeline and the second heat exchange circulation pipeline are used in conjunction to improve the heat dissipation efficiency.

[0031] The technical features and beneficial effects of the present invention are as follows:

[0032] 1. The present invention provides a contact port for the laser heat dissipation surface in the cooler cavity, fills the cavity with a cooling medium, and places the cooling medium in direct contact with the high-power laser heat dissipation surface. During the aging process, the heat generated by the high-power laser is rapidly transferred to the cooling medium through the heat dissipation surface, thereby rapidly dissipating the heat generated by the high-power laser. The present invention utilizes contact heat dissipation to eliminate the contact thermal resistance between the laser's heat dissipation surface and traditional water-cooled plates, significantly improving heat transfer performance. It also avoids the adverse effects of high-pressure cooling water on the laser's precision components.

[0033] 2. The present invention separates high-pressure cooling water from low-pressure cooling water through the first circulation pipe and the second circulation pipe, thereby preventing high-pressure water from adversely affecting the laser optical path while ensuring effective cooling. The water cooler and the copper pipe constitute a high-pressure circulation loop, which is used to cool the copper pipe to achieve and maintain the cooling of the cooling medium in the cooler. The water outlet pressure of the water cooler is about 0.3MPa, which is a high pressure for precision lasers. If it directly contacts the laser, it will have a slight effect on the laser optical path; the water tank, circulation pump and cavity constitute a low-pressure circulation loop. The connection method of the circulation pump is opposite. The water inlet end is connected to the cavity, which is equivalent to sucking the water in the water tank into the circulation pump. The pressure is small and can be ignored. The water outlet end of the circulation pump is connected to the water tank, and the outlet water will have a certain pressure, which is released in the water tank.

[0034] 3. The structural design of the present invention is reasonable. The second heat exchange circulation pipeline composed of the water tank and the circulation pump and the first heat exchange circulation pipeline jointly bear the heat exchange demand of the cooling medium. After the cooling medium circulates to the water tank, it can dissipate heat naturally in the external water tank environment, thereby improving the heat dissipation effect of the cooling medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic structural diagram of Example 1 of the present invention;

[0036] Figure 2 Schematic diagram of the cooler structure of embodiment 2 of the present invention

[0037] Figure 3 This is a schematic cross-sectional view of a cooler according to Example 2 of the present invention;

[0038] Figure 4 This is a schematic diagram of the application state of the cooler according to Example 2 of the present invention;

[0039] Figure 5 For the present invention Figure 4 Schematic diagram of vertical section of cooler in application state;

[0040] Including: 1. Cooler; 2. Laser; 3. Water chiller; 4. First heat exchange circulation pipeline; 5. Water tank; 6. Second heat exchange circulation pipeline; 7. Circulation pump; 8. Ball valve A; 9. Ball valve B; 10. Gasket;

[0041] 101. Contact port; 102. Copper tube; 103. Second circulation water inlet; 104. Second circulation water outlet; 105. First circulation water inlet; 106. First circulation water outlet; 107. Cavity; 108. Cooling medium; 109. Cooling water. DETAILED DESCRIPTION

[0042] The present invention will be further described below with reference to embodiments and accompanying drawings, but is not limited thereto.

[0043] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to needs to have a specific orientation, be constructed and operate in a specific orientation. Therefore, they cannot be understood as limiting the present invention.

[0044] Example 1:

[0045] like Figure 1-Figure 5 As shown, this embodiment provides a high-power laser contact aging cooling device, including a cooler 1, a first heat exchange circulation pipeline 4, and a second heat exchange circulation pipeline 6, wherein the cooler 1 includes a cavity and a cooling medium contact port on the laser heat dissipation surface connected to the cavity;

[0046] The second heat exchange circulation pipeline 6 includes a circulation pump 7 and a water tank 5, which provides cooling medium for the cavity;

[0047] The first heat exchange circulation pipeline 4 includes a copper tube 102 and a water chiller 3, wherein the copper tube 102 is bent or looped and arranged in the cavity of the cooler 1 to form a heat transfer body to provide heat exchange for the cooling medium in the cavity. The cooling medium 108 is deionized water.

[0048] The heat of the liquid inside the cavity 107 diffuses to the copper tube and is carried to the water cooler through the high-pressure circulation loop formed by the water cooler and the copper tube and dissipated. The heat of the laser is mainly dissipated through the chiller, and the high pressure inside the high-pressure circulation loop has no effect on the laser.

[0049] A first circulating water inlet 105 and a first circulating water outlet 106 are provided on one side of the cavity 107. The first circulating water inlet 105 and the first circulating water outlet 106 are used to connect the copper tube 102 and the chiller 3. A second circulating water inlet 103 and a second circulating water outlet 104 are also provided on the cavity. The second circulating water inlet 103 is used to connect the cavity and the water tank 5, and the second circulating water outlet 104 is used to connect the circulating pump 7 and the cavity.

[0050] There are four contact ports 101, and by setting up multiple contact ports, multiple lasers can be aged simultaneously. The bottom of the laser is in direct contact with the liquid in the cavity, which is conducive to the rapid diffusion of a large amount of heat from the laser into the liquid. The liquid pressure is low and has little impact on the laser housing.

[0051] The water inlet of the circulation pump 7 is connected to the cavity 107 , and the water outlet is connected to the water tank 5 .

[0052] The second heat exchange circulation pipeline and the cavity constitute a low-pressure circulation loop, and the water cooler and the copper pipe constitute a high-pressure circulation loop. The cooling water 109 output from the water cooler is high-pressure water with a pressure of about 0.3 MPa. For precision lasers, it is a high pressure and will have a slight effect on the optical path. The connection method of the circulation pump is opposite. The water inlet end is connected to the cavity, which is equivalent to sucking the water in the water tank into the circulation pump. This pressure is small and can be ignored. The water outlet end of the circulation pump is connected to the water tank, and the outlet water will have a certain pressure, which is released in the water tank.

[0053] The cooling method of the high-power laser contact aging cooling device comprises the following steps:

[0054] (1) Install the laser 2 on the cavity contact port 101, connect the copper pipe to the water cooler 3, connect the water inlet of the circulation pump 7 to the cavity, and connect the water outlet to the water tank;

[0055] (2) The circulation pump 7 and the water chiller 3 are started, the cavity 107 is filled with a cooling medium, and the cooling medium contacts the bottom of the laser 2;

[0056] (3) The laser 2 is subjected to an aging test. The heat generated by the laser 2 is directly diffused into the cooling medium in the cavity 107. The heat is brought into the water cooler 3 and dissipated through the high-pressure circulation loop formed by the water cooler 3 and the copper tube 102. The high pressure inside the high-pressure circulation loop has no effect on the laser 2. The circulation pump drives the cooling medium in the cavity 107 to flow, and simultaneously takes out part of the heat emitted by the laser 2. The first heat exchange circulation pipeline 4 and the second heat exchange circulation pipeline 6 are used in conjunction to improve the heat dissipation efficiency.

[0057] Example 2:

[0058] A high-power laser contact aging cooling device, as described in Example 1, except that two groups of copper tubes 102 are arranged in parallel on the left and right. Figure 3 As shown, they each have their own water inlet and outlet, which are connected to the water cooler. The copper tube has good heat conduction effect and is evenly distributed in the cavity, which can take away the heat in the cavity more quickly, avoiding the problem of high temperature near the water outlet when using a group of long copper tubes.

[0059] Example 3:

[0060] A high-power laser contact aging cooling device, as described in Example 1, differs in that the second circulation water inlet 103 and the second circulation water outlet 104 are arranged at the upper part of the cavity, which is conducive to the discharge of internal bubbles. The bubbles enter the water tank through the circulation pump and overflow from the water tank.

[0061] Example 4:

[0062] A high-power laser contact aging cooling device is as described in Example 1, except that a gasket 10 is provided on the cavity contact port 101, and the laser 2 is fixed to the contact port by screws. The gasket 10 serves as a seal between the components. Since the fixing hole positions are different for different lasers, the contact port can be opened according to actual conditions, and the size of the gasket is determined according to the laser.

[0063] Example 5:

[0064] A high-power laser contact aging cooling device is as described in Example 1, except that a ball valve A8 is provided on the pipe between the circulation pump 7 and the second circulation water outlet 104, and a ball valve B9 is provided on the pipe between the water tank 5 and the second circulation water inlet 103.

[0065] Test example:

[0066] The cooling device and cooling method described in Example 1 were used to simultaneously perform water-cooling aging on four lasers. The power of the semiconductor laser was set to 15 kW. A temperature sensor was installed on the laser housing to monitor the temperature change of the laser housing.

[0067] Comparative Example:

[0068] The existing water-cooling plate is used for aging test. A water-cooling channel is set inside the water-cooling plate. Four lasers are set on the upper side of the water-cooling plate. Aging is carried out with the same power as the test example. At the same time, a temperature sensor is set to detect the temperature of the laser shell, and the following data comparison is obtained. According to the data in the table below, the temperature change range of the laser in the test example is 17°-32°, the temperature change range of the laser in the comparative example is 24-45°, and the normal operating temperature range of the laser is 15°-35°. According to the data comparison, the cooling device of the present invention can ensure that the high-power laser is aged within the normal operating temperature range, while the temperature range change of the existing laser during cooling far exceeds the specified normal operating temperature range of the laser, which will greatly affect the aging test results.

[0069]

[0070] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high-power laser contact aging cooling device, characterized in that: The heat exchanger comprises a cooler, a first heat exchange circulation pipeline, and a second heat exchange circulation pipeline, wherein the cooler comprises a cavity and a cooling medium contact port on the laser heat dissipation surface connected to the cavity; The second heat exchange circulation pipeline includes a circulation pump and a water tank to provide cooling medium for the cavity; The first heat exchange circulation pipeline includes a copper tube and a water cooler, which is bent or surrounded in the cooler cavity to form a heat transfer body to provide heat exchange cooling for the cooling medium in the cavity.

2. The high-power laser contact aging cooling device according to claim 1, characterized in that: The cooling medium is at least one of deionized water, Freon, liquid ammonia, and liquid nitrogen.

3. The high-power laser contact aging cooling device according to claim 1, characterized in that: There are two groups of copper tubes, each of which is connected to a water cooler; Preferably, the two groups of copper tubes are arranged in parallel.

4. The high-power laser contact aging cooling device according to claim 1, characterized in that: A first circulating water inlet and a first circulating water outlet are provided on one side of the cavity, and the first circulating water inlet and the first circulating water outlet are used to connect the copper pipe and the chiller. A second circulating water inlet and a second circulating water outlet are also provided on the cavity, and the second circulating water inlet is used to connect the cavity and the water tank, and the second circulating water outlet is used to connect the circulating pump and the cavity.

5. The high-power laser contact aging cooling device according to claim 4, characterized in that: The second circulating water inlet and the second circulating water outlet are arranged at the upper part of the cavity.

6. The high-power laser contact aging cooling device according to claim 1, characterized in that: There is at least one contact port.

7. The high-power laser contact aging cooling device according to claim 6, characterized in that: A gasket is provided on the cavity contact port.

8. The high-power laser contact aging cooling device according to claim 4, characterized in that: A ball valve A is provided on the pipeline between the circulation pump and the second circulation water outlet, and a ball valve B is provided on the pipeline between the water tank and the second circulation water outlet.

9. The high-power laser contact aging cooling device according to claim 4, characterized in that: The water inlet end of the circulation pump is connected to the cavity, and the water outlet end is connected to the water tank.

10. The cooling method of the high-power laser contact aging cooling device according to claim 9, characterized in that: Here are the steps: (1) Install the laser on the cavity contact port, connect the copper pipe to the water cooler, connect the water inlet of the circulation pump to the cavity, and connect the water outlet to the water tank; (2) The circulation pump and water cooler are started, the cavity is filled with cooling water, and the cooling water contacts the bottom of the laser; (3) The laser undergoes aging test. The heat generated by the laser diffuses directly into the cooling water in the cavity. The heat is dissipated into the water cooler through the high-pressure circulation loop formed by the water cooler and the copper pipe. The high pressure inside the high-pressure circulation loop has no effect on the laser. The circulation pump drives the cooling water in the cavity to flow, and simultaneously takes out part of the heat emitted by the laser. The first heat exchange circulation pipeline and the second heat exchange circulation pipeline are used in conjunction to improve the heat dissipation efficiency.

Images