A laser processing device with adjustable low-temperature environment and its processing method

Abstract

The present invention relates to a laser processing device with adjustable low-temperature environment and its processing method. The laser processing device includes: a laser emission system, a laser transmission optical path, a beam scanning device, a low-temperature control device, a heat insulation device, and a control system. The low-temperature control device includes a cryogenic box, a liquid nitrogen delivery system, and a first normal-temperature gas delivery system. Both the liquid nitrogen delivery system and the first normal-temperature gas delivery system are connected to the cryogenic box; a workpiece mounting position is provided inside the cryogenic box; the heat insulation device covers the opening of the cryogenic box; the heat insulation device adopts a multi-layer light-transmitting glass structure, and the heat insulation device is connected to the second normal-temperature gas delivery system; the shaped laser beam irradiates the surface of the workpiece through the double-layer light-transmitting glass structure; the control system is used to control the laser emission system, the beam scanning device, the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system. The device has a simple structure, is easy to operate, does not require air drying, and has a low cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser processing, and particularly relates to a laser processing device with adjustable low-temperature environment and a processing method thereof. Background Art

[0002] Laser processing utilizes the energy of a laser, which is focused by a focusing lens to reach a high energy density at the focal point. After the material to be processed absorbs the laser, a photothermal effect is generated for processing. Due to its advantages such as good processing quality, high speed, non-contact, low pollution, high flexibility, and wide material adaptability, it has now become one of the important processing means. However, current laser processing is generally carried out at room temperature. For processing scenarios with high requirements such as a small heat-affected zone and no deformation of the material, it is difficult to meet the processing quality requirements; for example, when laser cutting thin film materials, heat-induced curling is likely to occur in a room temperature environment, and the thermal deformation of the material easily leads to changes in the laser focus, affecting the processing quality; in a low-temperature environment, the elongation rate of the material decreases and the brittleness increases. Utilizing the low-temperature physical properties of the material, both the heat-affected zone and the deformation amount generated during the laser processing process will be greatly reduced, which helps to improve the processing quality.

[0003] Methods for reducing the material temperature are usually achieved by means such as dry ice or liquid nitrogen. In an open environment, since the atmosphere contains a large amount of water molecules, a layer of water mist is easily formed on the surface of the low-temperature material when it meets cold. During laser processing, it will absorb and scatter the laser, resulting in a poor quality of the laser focus acting on the material, a decrease in power, and a slow processing efficiency; moreover, due to the continuous heat exchange between the material and the surrounding environment, the actual cooling effect is not good. Therefore, the best means is to place the material in a low-temperature and water-free environment, and the laser passes through the window glass for processing.

[0004] In addition, the processing effects will also vary greatly under different gas environment atmospheres. The material can promote the processing process in certain gas atmospheres. For example, adding inert gases such as argon can prevent the material from oxidizing; adding oxygen can improve the processing efficiency.

[0005] Currently existing enclosed low-temperature environment devices either have an unadjustable low-temperature environment and cannot meet the need to adjust the low-temperature environment based on the material characteristics, or have a small laser light inlet range and can only perform small-range processing, or only involve temperature environment adjustment and do not have the ability to add other auxiliary gases, resulting in limited application ranges. Therefore, the prior art has problems such as a small window range, only being applicable to small parts, slow temperature control speed, and low applicable scenarios for laser processing. Summary of the Invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a laser processing device with adjustable low-temperature environment and a processing method thereof. The technical problems to be solved by the present invention are achieved through the following technical solutions:

[0007] An embodiment of the present invention provides a laser processing device with adjustable low-temperature environment, including: a laser emission system, a laser transmission optical path, a beam scanning device, a low-temperature control device, a heat insulation device, and a control system. Among them,

[0008] The laser emission system is used to generate a laser beam; the laser transmission optical path is used to perform beam shaping on the laser beam and transmit it to the beam scanning device; the beam scanning device is used to control the shaped laser beam to move along a target trajectory and focus it on the workpiece to achieve a laser processing morphology with a set shape;

[0009] The low-temperature control device includes a cryogenic box, a liquid nitrogen delivery system, and a first normal-temperature gas delivery system. Both the liquid nitrogen delivery system and the first normal-temperature gas delivery system are connected to the cryogenic box and are used to deliver liquid nitrogen and normal-temperature gas into the cryogenic box in a preset ratio to control the temperature inside the cryogenic box; a workpiece installation position is provided inside the cryogenic box;

[0010] The heat insulation device covers the opening of the cryogenic box; the heat insulation device adopts a multi-layer light-transmitting glass structure, and the heat insulation device is connected to a second normal-temperature gas delivery system. The second normal-temperature gas delivery system is used to deliver normal-temperature gas into the chamber formed by the multi-layer light-transmitting glass structure; the shaped laser beam irradiates the surface of the workpiece through the double-layer light-transmitting glass structure;

[0011] The control system is used to control the laser emission system, the beam scanning device, the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system.

[0012] In an embodiment of the present invention, a cryogenic box liquid nitrogen inlet, a cryogenic box normal-temperature gas inlet, a cryogenic box outlet, a cryogenic box pressure relief valve, a temperature sensor, and a cryogenic box inlet baffle are provided on the cryogenic box. A workbench is provided inside the cryogenic box. Among them,

[0013] The cryogenic box liquid nitrogen inlet and the cryogenic box normal-temperature gas inlet are provided on one side wall of the cryogenic box. The cryogenic box liquid nitrogen inlet is connected to the liquid nitrogen delivery system, and the cryogenic box normal-temperature gas inlet is connected to the first normal-temperature gas delivery system;

[0014] The cryogenic box outlet is provided on another side wall of the cryogenic box; the cryogenic box pressure relief valve is provided on the cryogenic box outlet;

[0015] The temperature sensor is provided on the side wall of the cryogenic box and is connected to the control system through a temperature conversion module;

[0016] The baffle of the cryogenic box inlet is arranged on the inner wall of the cryogenic box and near the liquid nitrogen inlet and the normal temperature gas inlet of the cryogenic box;

[0017] The workbench is located at the bottom of the cryogenic box, and a tablet pressing clamp is arranged on the workbench, and the tablet pressing clamp is used to fix the workpiece on the workbench.

[0018] In an embodiment of the present invention, there is a 1-2 mm gap between the bottom of the workbench and the bottom of the cryogenic box;

[0019] The material of the workbench includes copper.

[0020] In an embodiment of the present invention, the liquid nitrogen delivery system includes a liquid nitrogen container, a liquid nitrogen transfer pipe, a first pressure gauge, and a first solenoid valve, and the first normal temperature gas delivery system includes a normal temperature gas container, a first normal temperature gas transfer pipe, a second pressure gauge, and a second solenoid valve. Among them,

[0021] The liquid nitrogen container is connected to the liquid nitrogen inlet of the cryogenic box through the liquid nitrogen transfer pipe, and the first pressure gauge and the first solenoid valve are sequentially arranged on the liquid nitrogen transfer pipe along the liquid nitrogen transfer direction, and the first solenoid valve is connected to the control system;

[0022] The normal temperature gas container is connected to the normal temperature gas inlet of the cryogenic box through the first normal temperature gas transfer pipe, and the second pressure gauge and the second solenoid valve are sequentially arranged on the first normal temperature gas transfer pipe along the normal temperature gas transfer direction, and the second solenoid valve is connected to the control system.

[0023] In an embodiment of the present invention, the heat insulation device includes a first heat insulation and light-transmitting glass, a second heat insulation and light-transmitting glass, a first fixing member, a second fixing member, a heat insulation device inlet, a heat insulation device outlet, a heat insulation device pressure relief valve, and a heat insulation device heat insulation pad. Among them,

[0024] The first heat insulation and light-transmitting glass is fixed on the first fixing member, and the second heat insulation and light-transmitting glass is fixed on the second fixing member;

[0025] The first fixing member and the second fixing member are stacked through the heat insulation device heat insulation pad;

[0026] The heat insulation device inlet is arranged on one side of the first fixing member or the second fixing member and is connected to the second normal temperature gas delivery system;

[0027] The heat insulation device outlet is arranged on the other side of the first fixing member or the second fixing member, and the heat insulation device pressure relief valve is arranged on the heat insulation device outlet.

[0028] In one embodiment of the present invention, the first heat-insulating and light-transmitting glass is fixed on the first fixing member through a first retaining ring, and a rubber pad is provided between the first retaining ring and the first heat-insulating and light-transmitting glass;

[0029] The second heat-insulating and light-transmitting glass is fixed on the second fixing member through a second retaining ring, and a rubber pad is provided between the second retaining ring and the second heat-insulating and light-transmitting glass;

[0030] The materials of the first fixing member and the second fixing member both include aluminum alloy, and the periphery of the aluminum alloy is wrapped with a heat-insulating material.

[0031] In one embodiment of the present invention, the second normal-temperature gas delivery system includes a normal-temperature gas container, a normal-temperature gas transmission pipe, a third pressure gauge, and a third solenoid valve. Among them,

[0032] The normal-temperature gas container is connected to the air inlet of the heat-insulating device through the normal-temperature gas transmission pipe. The third pressure gauge and the third solenoid valve are sequentially arranged on the normal-temperature gas transmission pipe along the normal-temperature gas transmission direction, and the third solenoid valve is connected to the control system.

[0033] Another embodiment of the present invention provides a processing method for a laser processing device with adjustable low-temperature environment, including the steps:

[0034] S1. Open the heat-insulating device from the cryogenic box, fix the workpiece at the workpiece installation position, and then fix the heat-insulating device on the cryogenic box;

[0035] S2. Control the delivery pressures of the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system through the control system;

[0036] S3. Use the control system to control the first normal-temperature gas delivery system to exhaust the air in the cryogenic box, and control the second normal-temperature gas delivery system to exhaust the air in the heat-insulating device;

[0037] S4. Close the first normal-temperature gas delivery system, open the liquid nitrogen delivery system, so that liquid nitrogen flows into the cryogenic box, and obtain the temperature in the cryogenic box in real time through the control system until the temperature reaches the set value, then close the liquid nitrogen delivery system;

[0038] S5. Use the control system to control the beam scanning device to perform trajectory scanning, and synchronously turn on the laser emission system;

[0039] S6. After the processing is completed, stop the beam scanning device and the laser emission system, close the second normal-temperature gas delivery system, open the first normal-temperature gas delivery system, so that the temperature in the cryogenic box rises to normal temperature, then close the first normal-temperature gas delivery system, take out the workpiece, and the processing is completed.

[0040] In one embodiment of the present invention, step S2 includes:

[0041] Set the pressure value of the first pressure gauge in the liquid nitrogen delivery system, the pressure value of the second pressure gauge in the first normal temperature gas delivery system, and the pressure value of the third pressure gauge in the second normal temperature gas delivery system through the control system, such that the pressure value of the third pressure gauge is 1 / 2 of the pressure value of the first pressure gauge.

[0042] In one embodiment of the present invention, step S3 includes:

[0043] Use the control system to control the opening of the second solenoid valve in the first normal temperature gas delivery system and the third solenoid valve in the second normal temperature gas delivery system to exhaust the air in the cryogenic chamber and the heat insulation device;

[0044] Step S4 includes:

[0045] Close the second solenoid valve, open the first solenoid valve of the liquid nitrogen delivery system, such that liquid nitrogen flows into the cryogenic chamber, and use the control system to obtain the temperature in the cryogenic chamber in real time through the temperature sensor until the temperature reaches the set value, then close the first solenoid valve;

[0046] Step S6 includes:

[0047] After processing is completed, stop the beam scanning device and the laser emission system, close the third solenoid valve, open the second solenoid valve, such that the temperature in the cryogenic chamber rises to normal temperature, then close the second solenoid valve, take out the workpiece, and the processing is completed.

[0048] Compared with the prior art, the beneficial effects of the present invention are:

[0049] 1. In the present invention, a liquid nitrogen delivery system and a first normal temperature gas delivery system are connected to the cryogenic chamber. By adjusting the opening time of the two, liquid nitrogen and normal temperature gas are mixed in a certain proportion, and thus the temperature in the chamber can be quickly and effectively adjusted; when the first normal temperature gas delivery system is closed and only the liquid nitrogen delivery system is opened, the lowest temperature of -196 °C can be reached. When the liquid nitrogen delivery system is closed and only the first normal temperature gas delivery system is opened, the temperature can reach normal temperature, thereby realizing that the working environment temperature is adjustable between -196 °C and 0 °C, and the temperature control speed is faster;

[0050] 2. The present invention uses multi-layer light-transmitting glass as the window glass, and normal temperature gas is filled between the multi-layer light-transmitting glasses, which can effectively prevent ultra-low temperature from being conducted to the first layer of window glass, such that the temperature of the window glass in contact with air is not lower than the dew condensation temperature, avoiding the generation of dew condensation on the window glass, and thus enabling high transmittance of laser energy to be transmitted to the workpiece;

[0051] 3. The present invention connects a second normal temperature gas delivery system to the heat insulation device. The pressure difference between the cryogenic box and the heat insulation device can be adjusted through a pressure control device, and the pressure is evenly distributed to the upper and lower light-transmitting glasses, enabling a larger area of the light-transmitting glass, a larger workpiece processing range, and larger workpiece sizes that can be processed.

[0052] 4. The present invention is provided with a pressure relief valve for the heat insulation device on the heat insulation device, which can ensure that the pressure of the light-transmitting glass is within the safe use range.

[0053] 5. The laser processing device with adjustable low-temperature environment of the present invention has a simple structure, is easy to operate, does not require air drying, and has a low cost. Brief Description of the Drawings

[0054] Figure 1 It is a schematic structural diagram of a laser processing device with adjustable low-temperature environment provided by an embodiment of the present invention;

[0055] Figure 2 It is a schematic structural diagram of a low-temperature control device provided by an embodiment of the present invention;

[0056] Figure 3 It is a schematic structural diagram of a heat insulation device provided by an embodiment of the present invention. Detailed Description of the Invention

[0057] The following further describes the present invention in detail with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0058] Embodiment 1

[0059] The purpose of this embodiment is to provide a device for laser processing with adjustable low-temperature environment, especially for ultra-low temperature processing environment below -70°C. Compared with the normal temperature processing environment, the ultra-low temperature processing environment has many processing advantages: 1. For materials prone to thermoplastic deformation, the ultra-low temperature environment can increase the brittleness of the materials and reduce plasticity. During laser processing, the materials are not easily deformed; 2. The ultra-low temperature environment can quickly reduce the temperature of the material surface during laser processing and reduce the heat-affected zone; 3. Processing in the ultra-low temperature environment can change the mechanical properties and organizational structure of the materials. The processed materials have stronger toughness, better mechanical properties, and lower internal stress.

[0060] Please refer to Figure 1 , Figure 1 It is a schematic structural diagram of a laser processing device with adjustable low-temperature environment provided by an embodiment of the present invention.

[0061] The laser processing device with adjustable low-temperature environment in this embodiment has various advantages such as a large processing range, adjustable low temperature, adjustable gas, and adjustable pressure, and includes a laser emission system 1, a laser transmission optical path 2, a beam scanning device 3, a low-temperature control device 4, a heat insulation device 5, and a control system 6.

[0062] Among them, the laser emission system 1 is used to generate a laser beam. The laser transmission optical path 2 is used to shape the laser beam and transmit it to the beam scanning device 3. The beam scanning device 3 is used to control the shaped laser beam to move along a target trajectory and focus it on the workpiece to achieve a laser processing topography with a set shape. The low-temperature control device 4 includes a cryogenic box 401, a liquid nitrogen delivery system, and a first normal-temperature gas delivery system; both the liquid nitrogen delivery system and the first normal-temperature gas delivery system are connected to the cryogenic box 401 and are used to deliver liquid nitrogen and normal-temperature gas into the cryogenic box 401 in a preset ratio to control the temperature inside the cryogenic box 401; specifically, the liquid nitrogen delivery system and the first normal-temperature gas delivery system control the temperature inside the cryogenic box 401 to be adjustable between -196°C and 0°C; a workpiece mounting position is provided inside the cryogenic box 401. The heat insulation device 5 covers the opening above the cryogenic box 401; the heat insulation device 5 adopts a multi-layer light-transmitting glass structure, and the heat insulation device 5 is connected to the second normal-temperature gas delivery system, and the second normal-temperature gas delivery system is used to deliver normal-temperature gas into the chamber formed by the multi-layer light-transmitting glass structure; the shaped laser beam irradiates the surface of the workpiece 7 through the double-layer light-transmitting glass structure. The control system 6 is electrically connected to the laser emission system 1, the beam scanning device 3, the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system respectively, and is used to control the laser emission system 1, the beam scanning device 3, the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system.

[0063] In this embodiment, normal-temperature gas and liquid nitrogen are mixed for temperature control, which can quickly achieve adjustable temperature control.

[0064] It should be noted that the heat insulation device 5 adopts a multi-layer light-transmitting glass structure, and the multi-layer light-transmitting glass structure can be two layers of light-transmitting glass, or three layers of light-transmitting glass, or four layers of light-transmitting glass, and so on.

[0065] In one embodiment, the laser transmission optical path 2 includes a beam expander 21, a reflector 22, and a reflector 23.

[0066] Please refer to Figure 2 , Figure 2 which is a schematic structural diagram of a low-temperature control device provided by an embodiment of the present invention.

[0067] In one embodiment, a liquid nitrogen inlet 402 for the cryogenic box, a normal-temperature gas inlet 403 for the cryogenic box, an outlet 404 for the cryogenic box, a pressure relief valve 405 for the cryogenic box, a temperature sensor 406, and an inlet baffle 407 for the cryogenic box are provided on the cryogenic box 401, and a workbench 408 is provided inside the cryogenic box 401.

[0068] Specifically, the liquid nitrogen inlet 402 of the cryogenic box and the normal-temperature gas inlet 403 of the cryogenic box are arranged on one side wall of the cryogenic box 401. The liquid nitrogen inlet 402 of the cryogenic box is connected to the liquid nitrogen delivery system, and the normal-temperature gas inlet 403 of the cryogenic box is connected to the first normal-temperature gas delivery system. The outlet 404 of the cryogenic box is arranged on the other side wall of the cryogenic box 401. The pressure relief valve 405 of the cryogenic box is arranged on the outlet 404 of the cryogenic box, and is used to discharge the gas in the cryogenic box and ensure pressure safety.

[0069] The temperature sensor 406 is arranged on the side wall of the cryogenic box 401, and is connected to the control system 6 through the temperature conversion module 20. Specifically, the temperature conversion module 20 can be a temperature A / D converter, and the control system 6 can be a computer; the temperature sensor 406 is connected to the temperature A / D converter 20, and the temperature sensor 406 is used to monitor the temperature in the cryogenic box and transmit the measured temperature of the cryogenic box to the computer.

[0070] The inlet baffle 407 of the cryogenic box is arranged on the inner wall of the cryogenic box 401 and near the liquid nitrogen inlet 402 and the normal-temperature gas inlet 403 of the cryogenic box, blocking the liquid nitrogen inlet 402 and the normal-temperature gas inlet 403 of the cryogenic box to prevent liquid nitrogen from splashing onto the workpiece 7 and the incoming gas flow field from causing the workpiece 7 to vibrate.

[0071] The workbench 408 is located at the bottom of the cryogenic box 401, and a tablet clamp 409 is arranged on the workbench 408. The tablet clamp 409 is used to fix the workpiece 7 on the workbench 408. Specifically, there is a 1-2 mm gap between the bottom of the workbench 408 and the bottom of the cryogenic box 401, which is conducive to the full contact between the workbench and liquid nitrogen, improving the cooling rate and quickly achieving cooling. The material of the workbench 408 includes copper, which has a faster heat conductivity.

[0072] In one embodiment, the liquid nitrogen delivery system includes a liquid nitrogen container 410, a liquid nitrogen transfer pipe 411, a first pressure gauge 412, and a first solenoid valve 413. The first normal-temperature gas delivery system includes a normal-temperature gas container 414, a first normal-temperature gas transfer pipe 415, a second pressure gauge 416, and a second solenoid valve 417.

[0073] Specifically, the liquid nitrogen container 410 is connected to the liquid nitrogen inlet 402 of the cryogenic box through the liquid nitrogen transfer pipe 411. The first pressure gauge 412 and the first solenoid valve 413 are sequentially arranged on the liquid nitrogen transfer pipe 411 along the liquid nitrogen transfer direction, and the first solenoid valve 413 is connected to the control system 6.

[0074] It can be understood that the liquid nitrogen inlet 402 of the cryogenic box is directly connected to the liquid nitrogen container 410, and the first pressure gauge 412 and the first solenoid valve 413 are installed in sequence in the middle. The first pressure gauge 412 is used to control the inlet pressure and thus control the liquid nitrogen flow rate. The first solenoid valve 413 is connected to the computer and controls whether to intake gas according to the temperature set by the computer.

[0075] The normal temperature gas container 414 is connected to the normal temperature gas inlet 403 of the cryogenic box through the first normal temperature gas transfer pipe 415. The second pressure gauge 416 and the second solenoid valve 417 are arranged on the first normal temperature gas transfer pipe 415 in sequence along the normal temperature gas transfer direction. The second solenoid valve 417 is connected to the control system 6.

[0076] It can be understood that the normal temperature gas inlet 403 of the cryogenic box is directly connected to the normal temperature gas container 414, and the second pressure gauge 416 and the second solenoid valve 417 are installed in the middle. The second pressure gauge 416 is used to control the inlet pressure and thus control the normal temperature gas flow rate. The second solenoid valve 417 is connected to the computer and controls whether to intake gas according to the temperature set by the computer.

[0077] In this embodiment, the first solenoid valve 413 and the second solenoid valve 417 are connected to the computer. The computer can control the on-off states of the first solenoid valve 413 and the second solenoid valve 417 according to the temperature of the temperature sensor, so as to adjust the internal temperature of the cryogenic box.

[0078] Please refer to Figure 3 , Figure 3 which is a schematic structural diagram of a heat insulation device provided by an embodiment of the present invention.

[0079] In one embodiment, the heat insulation device 5 includes a first heat insulation and light-transmitting glass 501, a second heat insulation and light-transmitting glass 502, a first fixing member 503, a second fixing member 504, a heat insulation device gas inlet 505, a heat insulation device gas outlet 506, a heat insulation device pressure relief valve 507, and a heat insulation device heat insulation pad 508.

[0080] Specifically, the first heat insulation and light-transmitting glass 501 is fixed on the first fixing member 503, and the second heat insulation and light-transmitting glass 502 is fixed on the second fixing member 504. The first fixing member 503 and the second fixing member 504 are stacked through the heat insulation device heat insulation pad 508. The heat insulation device gas inlet 505 is arranged on one side of the first fixing member 503 or the second fixing member 504 and is connected to the second normal temperature gas delivery system. The heat insulation device gas outlet 506 is arranged on the other side of the first fixing member 503 or the second fixing member 504, and the heat insulation device pressure relief valve 507 is arranged on the heat insulation device gas outlet 506.

[0081] Furthermore, the first heat insulation and light-transmitting glass 501 is fixed on the first fixing member 503 through a first retaining ring, and a rubber pad is arranged between the first retaining ring and the first heat insulation and light-transmitting glass 501. The second heat insulation and light-transmitting glass 502 is fixed on the second fixing member 504 through a second retaining ring, and a rubber pad is arranged between the second retaining ring and the second heat insulation and light-transmitting glass 502. The laser beam irradiates the workpiece 7 after passing through the light-transmitting glasses 501 and 502.

[0082] To prevent the lower transparent glass from transferring low temperature to the upper transparent glass and causing condensation, and to keep the upper transparent glass always above 0°C, the most common method is to evacuate the space between the upper and lower transparent glasses of the heat insulation device. However, after evacuation, the upper and lower transparent glasses will bear a huge atmospheric pressure and are prone to breakage. In this embodiment, an adiabatic design is carried out between the two transparent glasses of the heat insulation device, and an inert gas is filled between the two transparent glasses. The inert gas has a lower thermal conductivity than air and is not easy to conduct heat. At the same time, the inert gas flows dynamically in and out of the isolation layer to conduct the generated low temperature out in time.

[0083] In this embodiment, the two transparent glasses are fixed by a retaining ring, and there is a rubber pad between the retaining ring and the transparent glass, which can avoid the generation of local stress on the retaining ring, make the force evenly distributed, and effectively seal to prevent gas leakage.

[0084] In this embodiment, the fixing parts for fixing the upper and lower transparent glasses are isolated by a heat insulation pad 508 of the heat insulation device to prevent low temperature from being conducted from the lower fixing part to the upper fixing part.

[0085] In this embodiment, a pressure relief valve of the heat insulation device is provided at the air outlet of the heat insulation device to prevent the internal pressure of the heat insulation device from being too high.

[0086] In one embodiment, the second normal temperature gas delivery system includes a normal temperature gas container 414, a normal temperature gas transmission pipe 509, a third pressure gauge 510, and a third solenoid valve 511. Among them, the normal temperature gas container 414 is connected to the air inlet 505 of the heat insulation device through the normal temperature gas transmission pipe 509. The third pressure gauge 510 and the third solenoid valve 511 are arranged on the normal temperature gas transmission pipe 509 in sequence along the normal temperature gas transmission direction, and the third solenoid valve 511 is connected to the control system 6.

[0087] Specifically, the third pressure gauge 510 is used to adjust the intake pressure. The third solenoid valve 511 is connected to a computer, and the computer controls the opening and closing of the third solenoid valve 511 according to the pressure change at the pressure relief valve, thereby controlling whether to intake air.

[0088] Furthermore, the materials of the first fixing part 503 and the second fixing part 504 both include aluminum alloy, and the aluminum alloy is wrapped with heat insulation materials.

[0089] Furthermore, there is a rubber pad between the cryogenic box 401 and the heat insulation device 5, and they are connected by screws

[0090] It should be noted that the normal temperature gas in this embodiment can be a normal temperature inert gas, which can be replaced with other types of gases according to the test requirements, increasing the range of test conditions and having a wider range of use scenarios.

[0091] In this embodiment, a liquid nitrogen delivery system and a first normal-temperature gas delivery system are connected to the cryogenic box. By adjusting the opening time of both, liquid nitrogen and normal-temperature gas are mixed in a certain proportion, enabling rapid and effective adjustment of the temperature inside the cavity. When the first normal-temperature gas delivery system is closed and only the liquid nitrogen delivery system is opened, the lowest temperature of -196°C can be achieved. When the liquid nitrogen delivery system is closed and only the first normal-temperature gas delivery system is opened, the temperature can reach normal temperature, thus realizing that the working environment temperature can be adjusted between -196°C and 0°C, and the temperature control speed is faster.

[0092] In this embodiment, multi-layer light-transmitting glass is used as the window glass, and normal-temperature gas is filled between the multi-layer light-transmitting glass, which can effectively prevent ultra-low temperature from being conducted to the first-layer window glass, ensuring that the temperature of the window glass in contact with air is not lower than the dew condensation temperature, avoiding the occurrence of dew condensation on the window glass, and thus enabling high transmittance of laser energy to be transmitted to the workpiece.

[0093] In this embodiment, a second normal-temperature gas delivery system is connected to the heat insulation device. The pressure difference between the cryogenic box and the heat insulation device can be adjusted through a pressure control device, and the pressure is evenly distributed to the upper and lower light-transmitting glasses, enabling a larger light-transmitting glass area, a larger workpiece processing range, and larger workpiece sizes that can be processed.

[0094] In this embodiment, a pressure relief valve for the heat insulation device is provided on the heat insulation device, which can ensure that the pressure of the light-transmitting glass is within the safe operating range.

[0095] The laser processing device with adjustable low-temperature environment in this embodiment has a simple structure, is easy to operate, does not require air drying, and has a low cost.

[0096] Embodiment 2

[0097] Based on Embodiment 1, this embodiment also provides a processing method for a laser processing device with an adjustable low-temperature environment. The processing method includes the steps:

[0098] S1. Open the heat insulation device 5 from the cryogenic box 401, fix the workpiece 7 at the workpiece installation position, and then fix the heat insulation device 5 on the cryogenic box 401.

[0099] Specifically, first, open the heat insulation device 5 from the cryogenic box 401 and remove it; then fix the workpiece 7 on the workbench 408 and clamp it tightly with the pressing clip 409; afterwards, install the heat insulation device 5 on the cryogenic box 401, tighten the screws, and ensure the sealing of the cryogenic box 401.

[0100] S2. Control the delivery pressures of the liquid nitrogen delivery system, the first normal-temperature gas delivery system, and the second normal-temperature gas delivery system through the control system 6.

[0101] Specifically, turn on the computer and set the pressure values of the first pressure gauge 412 in the liquid nitrogen delivery system, the second pressure gauge 416 in the first normal temperature gas delivery system, and the third pressure gauge 510 in the second normal temperature gas delivery system. Among them, the set values of the first pressure gauge 412 and the second pressure gauge 416 are not greater than 1 MPa, and the pressure value of the third pressure gauge 510 is 1 / 2 of the set value of the first pressure gauge 412, so as to evenly distribute the air pressure generated by the cryogenic box to the light-transmitting glass.

[0102] S3. Use the control system 6 to control the first normal temperature gas delivery system to exhaust the air in the cryogenic box 401, and control the second normal temperature gas delivery system to exhaust the air in the heat insulation device 5.

[0103] Specifically, use the control system 6 to control the second solenoid valve 417 in the first normal temperature gas delivery system and the third solenoid valve 511 in the second normal temperature gas delivery system to open, exhaust the air in the cryogenic box 401 and the heat insulation device 5, and continue for 5 minutes.

[0104] S4. Close the first normal temperature gas delivery system, turn on the liquid nitrogen delivery system, so that liquid nitrogen flows into the cryogenic box 401, and use the control system 6 to obtain the temperature in the cryogenic box 401 in real time until the temperature reaches the set value, and then close the liquid nitrogen delivery system.

[0105] Specifically, close the second solenoid valve 417, open the first solenoid valve 413 of the liquid nitrogen delivery system, so that liquid nitrogen flows into the cryogenic box 401, and use the control system 6 to read the temperature in the cryogenic box 401 measured by the temperature sensor 406 in real time until the temperature reaches the set value, and then close the first solenoid valve 413.

[0106] S5. Use the control system 6 to control the beam scanning device 3 to perform trajectory scanning, and synchronously turn on the laser emission system 1.

[0107] S6. After processing is completed, stop the beam scanning device 3 and the laser emission system 1, and close the second normal temperature gas delivery system. Open the first normal temperature gas delivery system, so that the temperature in the cryogenic box 401 rises to normal temperature. Then close the first normal temperature gas delivery system, take out the workpiece 7, and the processing is completed.

[0108] Specifically, after processing is completed, stop the beam scanning device 3 and the laser emission system 1. At the same time, close the third solenoid valve 511 and open the second solenoid valve 417, so that normal temperature gas flows into the cryogenic box 401, and its temperature gradually rises to normal temperature; after the temperature rises to normal temperature, close the second solenoid valve 417. Open the screw between the heat insulation device and the cryogenic box, take out the workpiece 7, and the processing is completed.

[0109] The processing method of this embodiment is easy to operate, does not require air drying, and has a low cost.

[0110] The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A laser processing device with adjustable low-temperature environment, characterized in that Comprising: a laser emission system (1), a laser transmission optical path (2), a beam scanning device (3), a cryogenic control device (4), a heat insulation device (5) and a control system (6), wherein, the laser emission system (1) is used to generate a laser beam; the laser transmission optical path (2) is used to perform beam shaping on the laser beam and transmit it to the beam scanning device (3); the beam scanning device (3) is used to control the shaped laser beam to move along a target trajectory and focus it on a workpiece to achieve a laser processing topography of a set shape; the cryogenic control device (4) includes a cryogenic box (401), a liquid nitrogen delivery system and a first normal temperature gas delivery system, the liquid nitrogen delivery system and the first normal temperature gas delivery system are both connected to the cryogenic box (401) and are used to deliver liquid nitrogen and normal temperature gas into the cryogenic box (401) in a preset ratio to control the temperature inside the cryogenic box (401); a workpiece mounting position is provided inside the cryogenic box (401); the heat insulation device (5) covers the opening of the cryogenic box (401); the heat insulation device (5) adopts a multi-layer light-transmitting glass structure, and the heat insulation device (5) is connected to a second normal temperature gas delivery system, and the second normal temperature gas delivery system is used to deliver normal temperature gas into the chamber formed by the multi-layer light-transmitting glass structure; the shaped laser beam irradiates the surface of the workpiece (7) through the multi-layer light-transmitting glass structure; the control system (6) is used to control the laser emission system (1), the beam scanning device (3), the liquid nitrogen delivery system, the first normal temperature gas delivery system and the second normal temperature gas delivery system.

2. The laser processing device with adjustable low-temperature environment according to claim 1, wherein The cryogenic box (401) is provided with a cryogenic box liquid nitrogen inlet (402), a cryogenic box normal temperature gas inlet (403), a cryogenic box outlet (404), a cryogenic box pressure relief valve (405), a temperature sensor (406) and a cryogenic box inlet baffle (407), and a workbench (408) is provided inside the cryogenic box (401), wherein, the cryogenic box liquid nitrogen inlet (402) and the cryogenic box normal temperature gas inlet (403) are provided on one side wall of the cryogenic box (401), the cryogenic box liquid nitrogen inlet (402) is connected to the liquid nitrogen delivery system, and the cryogenic box normal temperature gas inlet (403) is connected to the first normal temperature gas delivery system; the cryogenic box outlet (404) is provided on the other side wall of the cryogenic box (401); the cryogenic box pressure relief valve (405) is provided on the cryogenic box outlet (404); the temperature sensor (406) is provided on the side wall of the cryogenic box (401) and is connected to the control system (6) through a temperature conversion module (20); the cryogenic box inlet baffle (407) is provided on the inner wall of the cryogenic box (401) and is near the cryogenic box liquid nitrogen inlet (402) and the cryogenic box normal temperature gas inlet (403); The workbench (408) is located at the bottom of the cryogenic box (401), and a tablet press clamp (409) is arranged on the workbench (408). The tablet press clamp (409) is used to fix the workpiece (7) on the workbench (408).

3. The laser processing device with adjustable low-temperature environment according to claim 2, wherein There is a gap of 1 - 2 mm between the bottom of the workbench (408) and the bottom of the cryogenic box (401); The material of the workbench (408) includes copper.

4. The laser processing device with adjustable low-temperature environment according to claim 2, characterized in that, The liquid nitrogen delivery system includes a liquid nitrogen container (410), a liquid nitrogen transfer pipe (411), a first pressure gauge (412), and a first solenoid valve (413). The first normal temperature gas delivery system includes a normal temperature gas container (414), a first normal temperature gas transfer pipe (415), a second pressure gauge (416), and a second solenoid valve (417). Among them, The liquid nitrogen container (410) is connected to the liquid nitrogen inlet (402) of the cryogenic box through the liquid nitrogen transfer pipe (411). The first pressure gauge (412) and the first solenoid valve (413) are arranged on the liquid nitrogen transfer pipe (411) in sequence along the liquid nitrogen transfer direction. The first solenoid valve (413) is connected to the control system (6); The normal temperature gas container (414) is connected to the normal temperature gas inlet (403) of the cryogenic box through the first normal temperature gas transfer pipe (415). The second pressure gauge (416) and the second solenoid valve (417) are arranged on the first normal temperature gas transfer pipe (415) in sequence along the normal temperature gas transfer direction. The second solenoid valve (417) is connected to the control system (6).

5. The laser processing device with adjustable low-temperature environment according to claim 1, wherein The heat insulation device (5) includes a first heat insulation and light-transmitting glass (501), a second heat insulation and light-transmitting glass (502), a first fixing member (503), a second fixing member (504), a heat insulation device air inlet (505), a heat insulation device air outlet (506), a heat insulation device pressure relief valve (507), and a heat insulation device heat insulation pad (508). Among them, The first heat insulation and light-transmitting glass (501) is fixed on the first fixing member (503), and the second heat insulation and light-transmitting glass (502) is fixed on the second fixing member (504); The first fixing member (503) and the second fixing member (504) are stacked through the heat insulation device heat insulation pad (508); The heat insulation device air inlet (505) is arranged on one side of the first fixing member (503) or the second fixing member (504) and is connected to the second normal temperature gas delivery system; The heat insulation device air outlet (506) is arranged on the other side of the first fixing member (503) or the second fixing member (504). The heat insulation device pressure relief valve (507) is arranged on the heat insulation device air outlet (506).

6. The laser processing device with adjustable low-temperature environment according to claim 5, characterized in that, The first heat insulation and light-transmitting glass (501) is fixed on the first fixing member (503) through a first retaining ring, and a rubber pad is arranged between the first retaining ring and the first heat insulation and light-transmitting glass (501); The second heat-insulating and light-transmitting glass (502) is fixed on the second fixing member (504) through a second retaining ring, and a rubber gasket is arranged between the second retaining ring and the second heat-insulating and light-transmitting glass (502); The materials of the first fixing member (503) and the second fixing member (504) both include aluminum alloy, and the periphery of the aluminum alloy is wrapped with heat-insulating materials.

7. The laser processing device with adjustable low-temperature environment according to claim 5, characterized in that, The second normal-temperature gas delivery system includes a normal-temperature gas container (414), a normal-temperature gas transmission pipe (509), a third pressure gauge (510) and a third solenoid valve (511), wherein, The normal-temperature gas container (414) is connected to the air inlet (505) of the heat-insulating device through the normal-temperature gas transmission pipe (509), the third pressure gauge (510) and the third solenoid valve (511) are sequentially arranged on the normal-temperature gas transmission pipe (509) along the normal-temperature gas transmission direction, and the third solenoid valve (511) is connected to the control system (6).

8. A processing method using the laser processing device with adjustable low-temperature environment according to any one of claims 1-7, characterized in that, Including steps: S1. Open the heat-insulating device (5) from the cryogenic box (401), fix the workpiece (7) at the workpiece installation position, and then fix the heat-insulating device (5) on the cryogenic box (401); S2. Control the delivery pressures of the liquid nitrogen delivery system, the first normal-temperature gas delivery system and the second normal-temperature gas delivery system through the control system (6); S3. Use the control system (6) to control the first normal-temperature gas delivery system to exhaust the air in the cryogenic box (401), and control the second normal-temperature gas delivery system to exhaust the air in the heat-insulating device (5); S4. Close the first normal-temperature gas delivery system, open the liquid nitrogen delivery system, so that liquid nitrogen flows into the cryogenic box (401), and obtain the temperature in the cryogenic box (401) in real time through the control system (6) until the temperature reaches the set value, and then close the liquid nitrogen delivery system; S5. Use the control system (6) to control the beam scanning device (3) to perform trajectory scanning, and synchronously turn on the laser emission system (1); S6. After processing is completed, stop the beam scanning device (3) and the laser emission system (1), close the second normal-temperature gas delivery system, open the first normal-temperature gas delivery system, so that the temperature in the cryogenic box (401) rises to normal temperature, then close the first normal-temperature gas delivery system, take out the workpiece (7), and the processing is completed.

9. The processing method of the laser processing device with adjustable low-temperature environment according to claim 8, characterized in that, Step S2 includes: Set the pressure value of the first pressure gauge (412) in the liquid nitrogen delivery system, the pressure value of the second pressure gauge (416) in the first normal-temperature gas delivery system and the pressure value of the third pressure gauge (510) in the second normal-temperature gas delivery system through the control system (6), so that the pressure value of the third pressure gauge (510) is 1 / 2 of the pressure value of the first pressure gauge (412).

10. The processing method of the laser processing device with adjustable low-temperature environment according to claim 8, characterized in that, Step S3 includes: Use the control system (6) to control the second solenoid valve (417) in the first normal-temperature gas delivery system and the third solenoid valve (511) in the second normal-temperature gas delivery system to open, and exhaust the air in the cryogenic box (401) and the heat-insulating device (5); Step S4 includes: Close the second solenoid valve (417), open the first solenoid valve (413) of the liquid nitrogen delivery system, so that liquid nitrogen flows into the cryogenic chamber (401), and use the control system (6) to obtain the temperature inside the cryogenic chamber (401) in real time through the temperature sensor (406) until the temperature reaches the set value, then close the first solenoid valve (413); Step S6 includes: After processing is completed, stop the beam scanning device (3) and the laser emission system (1), close the third solenoid valve (511), open the second solenoid valve (417), so that the temperature inside the cryogenic chamber (401) rises to room temperature, then close the second solenoid valve (417), take out the workpiece (7), and the processing is completed.

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