Laser cooling system and control method thereof, laser and laser processing equipment

Abstract

The invention provides a laser cooling system and a control method thereof, a laser and laser processing equipment. The laser cooling system comprises an evaporator, a liquid storage container, a refrigerant pump and a first flow regulating valve, the evaporator is used for cooling a heating device of the laser, the liquid storage container is used for storing a liquid refrigerant, the refrigerant pump is connected between the liquid storage container and the evaporator, and the first flow regulating valve is connected with the refrigerant pump in parallel. The first flow regulating valve is used for forming a loop with the refrigerant pump and regulating the pressure of the refrigerant pump. The control method comprises the steps that the evaporation pressure in the evaporator is obtained; and according to the evaporation pressure, the opening degree of the first flow adjusting valve is adjusted, and the pressure of the refrigerant pump is adjusted. According to the embodiment of the invention, the evaporation pressure in the evaporator is not too low to influence the light emitting quality of the laser, and the light emitting stability of the laser is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lasers, and particularly to a laser cooling system and its control method, a laser, and a laser processing device. Background Art

[0002] A related technology proposes a direct-cooled laser that uses a compression refrigeration cycle to directly evaporate and exchange heat of a refrigerant in a cold plate to achieve heat dissipation of a laser device. However, in a low-temperature ambient temperature, such as -20°C to 0°C, as the ambient temperature decreases, the suction pressure of the compressor also gradually decreases, resulting in a low overall mass flow rate of the refrigerant in the cooling system, making it difficult to meet the heat dissipation requirements of the laser and limiting the use of the laser. Summary of the Invention

[0003] Embodiments of the present invention provide a laser cooling system and its control method, a laser, and a laser processing device to prevent the evaporation pressure in the evaporator from being too low and affecting the light output quality of the laser, and improve the light output stability of the laser.

[0004] In a first aspect, an embodiment of the present invention provides a control method for a laser cooling system. The cooling system includes an evaporator, a liquid storage container, a refrigerant pump, and a first flow regulating valve. The evaporator is used to cool a heat-generating device of the laser, the liquid storage container is used to store liquid refrigerant, the refrigerant pump is connected between the liquid storage container and the evaporator, and the first flow regulating valve is connected in parallel with the refrigerant pump. The first flow regulating valve is used to form a loop with the refrigerant pump and regulate the pressure of the refrigerant pump.

[0005] The control method includes:

[0006] Obtaining the evaporation pressure in the evaporator;

[0007] Adjusting the opening degree of the first flow regulating valve according to the evaporation pressure to regulate the pressure of the refrigerant pump.

[0008] Optionally, adjusting the opening degree of the first flow regulating valve to regulate the pressure of the refrigerant pump includes:

[0009] If the opening degree of the first flow regulating valve is less than a first opening degree threshold, increasing the opening degree of the first flow regulating valve to boost the pressure of the refrigerant pump; and / or, if the opening degree of the first flow regulating valve is greater than or equal to the first opening degree threshold, decreasing the opening degree of the first flow regulating valve to boost the pressure of the refrigerant pump.

[0010] Optionally, before obtaining the evaporation pressure in the evaporator, it further includes:

[0011] Setting the opening degree of the first flow regulating valve according to the light output power of the laser.

[0012] Optionally, set the opening degree of the first flow regulating valve according to the light output power of the laser, including:

[0013] If the opening degree of the first flow regulating valve is less than the first opening threshold: If the light output power is less than the first threshold, the opening degree of the first flow regulating valve is within the first opening range; If the light output power is greater than or equal to the first threshold and less than the second threshold, the opening degree of the first flow regulating valve is within the second opening range; The value in the second opening range is greater than the value in the first opening range; The first threshold is less than the second threshold; If the light output power is greater than or equal to the second threshold, the opening degree of the first flow regulating valve is within the third opening range; The value in the third opening range is greater than the value in the second opening range;

[0014] If the opening degree of the first flow regulating valve is greater than or equal to the first opening threshold: If the light output power is less than the first threshold, the opening degree of the first flow regulating valve is within the fourth opening range, and the value in the fourth opening range is greater than the value in the third opening range; If the light output power is greater than or equal to the first threshold and less than the second threshold, the opening degree of the first flow regulating valve is within the fifth opening range; The value in the fifth opening range is greater than the value in the third opening range and less than the value in the fourth opening range; If the light output power is greater than or equal to the second threshold, the opening degree of the first flow regulating valve is within the sixth opening range; The value in the sixth opening range is greater than the value in the third opening range and less than the value in the fifth opening range.

[0015] Optionally, the cooling system further includes a condenser and a compressor. The compressor is connected between the condenser and the evaporator, and the condenser is connected between the compressor and the liquid storage container. Gaseous refrigerant enters the compressor, and the compressed gaseous refrigerant enters the condenser for heat exchange to form liquid refrigerant;

[0016] Before setting the opening degree of the first flow regulating valve according to the light output power of the laser, it further includes:

[0017] Obtain the rotation speed of the refrigerant pump;

[0018] Among them, the step of setting the opening degree of the first flow regulating valve according to the light output power of the laser includes:

[0019] If the rotation speed of the refrigerant pump reaches the maximum rotation speed, set the opening degree of the first flow regulating valve according to the light output power of the laser;

[0020] After obtaining the rotation speed of the refrigerant pump, it further includes:

[0021] If the rotational speed of the refrigerant pump does not reach the maximum rotational speed, increase the rotational speed of the refrigerant pump.

[0022] Optionally, the cooling system further includes a fan, and the fan provides air volume for heat dissipation of the condenser;

[0023] Before setting the opening degree of the first flow regulating valve according to the light output power of the laser, it further includes:

[0024] Obtain the rotational speed of the fan;

[0025] Wherein, the step of setting the opening degree of the first flow regulating valve according to the light output power of the laser includes:

[0026] If the fan stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed, set the opening degree of the first flow regulating valve according to the light output power of the laser;

[0027] After obtaining the rotational speed of the fan, it further includes:

[0028] If the fan does not stop rotating, reduce the rotational speed of the fan.

[0029] Optionally, before obtaining the rotational speed of the refrigerant pump, it further includes:

[0030] Obtain the condensation pressure at the outlet of the condenser and the light output power of the laser;

[0031] Wherein, the step of obtaining the rotational speed of the refrigerant pump includes:

[0032] If the condensation pressure is less than or equal to the second preset pressure value, obtain the rotational speed of the refrigerant pump.

[0033] Optionally, before obtaining the evaporation pressure in the evaporator, it further includes:

[0034] Obtain the ambient temperature;

[0035] If the ambient temperature is less than the preset temperature value, control the refrigeration mode of the cooling system to include the refrigerant pump refrigeration mode, and in the refrigerant pump refrigeration mode, the refrigerant pump provides refrigeration.

[0036] In a second aspect, an embodiment of the present invention provides a cooling system for a laser, and the cooling system includes an evaporator, a condenser, a liquid storage container, and a second flow regulating valve connected in sequence; the cooling system further includes a compressor, and the compressor is connected between the evaporator and the condenser;

[0037] The evaporator is used to cool the heating components of the laser; gaseous refrigerant enters the compressor, and the compressed gaseous refrigerant enters the condenser for heat exchange to form liquid refrigerant; the liquid storage container is used to store the liquid refrigerant;

[0038] The cooling system further includes a refrigerant pump, a check valve, and a first flow regulating valve; the refrigerant pump is connected between the liquid storage container and the evaporator for pressurizing the liquid refrigerant;

[0039] The check valve is in parallel with the compressor, and the first flow regulating valve is in parallel with the refrigerant pump. The first flow regulating valve is used to form a circuit with the refrigerant pump and regulate the pressure of the refrigerant pump.

[0040] Optionally, the cooling system further includes a blower, and the blower provides air volume for heat dissipation of the condenser.

[0041] In a third aspect, an embodiment of the present invention provides a laser, including the cooling system described in the second aspect; and an optical device.

[0042] In a fourth aspect, an embodiment of the present invention provides a laser processing device, including the laser described in the third aspect.

[0043] For the control method of the laser cooling system provided by the embodiment of the present invention, if the evaporation pressure is less than or equal to the first preset pressure value, the opening of the first flow regulating valve is adjusted to boost the refrigerant pump. The first flow regulating valve is in parallel with the refrigerant pump, so that the first flow regulating valve and the refrigerant pump form a bypass circuit. Under the cyclic boosting effect of the refrigerant pump, the refrigerant pressure at the outlet of the refrigerant pump is increased. Through the combined action of the first flow regulating valve and the refrigerant pump, the evaporation pressure in the evaporator is increased, thereby improving the refrigeration capacity of the evaporator, ensuring that the evaporation pressure in the evaporator will not be too low to affect the light output quality of the laser, and improving the light output stability of the laser. Description of the Drawings

[0044] Figure 1 It is a schematic diagram of a cooling system of a laser provided by an embodiment of the present invention;

[0045] Figure 2 It is a flowchart of a control method of a laser cooling system provided by an embodiment of the present invention;

[0046] Figure 3 It is a flowchart of another control method of a laser cooling system provided by an embodiment of the present invention;

[0047] Figure 4 It is a flowchart of another control method of a laser cooling system provided by an embodiment of the present invention;

[0048] Figure 5 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention;

[0049] Figure 6 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention;

[0050] Figure 7 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention;

[0051] Figure 8 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention;

[0052] Figure 9 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention;

[0053] Figure 10 Flowchart of another control method for the laser cooling system provided by the embodiment of the present invention.

[0054] Wherein, 11 is the evaporator; 12 is the compressor; 13 is the condenser; 14 is the liquid storage container; 15 is the refrigerant pump; 16 is the second flow regulating valve; 17 is the check valve; 18 is the first flow regulating valve. Specific embodiments

[0055] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only the parts related to the present invention are shown in the accompanying drawings rather than all the structures.

[0056] It has been found through research that when the laser emits light and the ambient temperature is low, the system is in the refrigerant pump refrigeration mode. When the ambient temperature is very low, such as -20°C to 0°C, the fan may operate at a low speed or stop running. In this case, the condensation pressure is very low; even with the pressurization of the refrigerant pump 15, the evaporation pressure will also be on the low side.

[0057] Figure 1 Schematic diagram of a cooling system for a laser provided by the embodiment of the present invention, refer to Figure 1, the laser includes a cooling system and optical devices. The optical devices are the main heat-generating components during the operation of the laser. When the laser is operating, the temperature of the optical devices will rise, and refrigeration is required through the cooling system to maintain a suitable operating temperature. The cooling system provides refrigeration for the heat-generating components including the optical devices. In addition to the optical devices, the heat-generating components may also include other elements, such as circuit elements and / or mechanical elements. The cooling system includes an evaporator 11, a condenser 13, a liquid storage container 14, and a second flow regulating valve 16 connected in sequence. The cooling system also includes a compressor 12, and the compressor 12 is connected between the evaporator 11 and the condenser 13. The evaporator 11 is used to cool the heat-generating components of the laser. The heat-generating components include, but are not limited to, the pump source, optical fiber, mode stripper, beam combiner, adapter, and optical lens of the laser. The gaseous refrigerant enters the compressor 12, and the compressed gaseous refrigerant enters the condenser 13 for heat exchange to form a liquid refrigerant. The liquid storage container 14 is used to store the liquid refrigerant. The second flow regulating valve 16 is used to control its opening degree according to the control instruction.

[0058] The cooling system also includes a refrigerant pump 15 and a first flow regulating valve 18. The refrigerant pump 15 is connected between the liquid storage container 14 and the evaporator 11, and the refrigerant pump 15 is used to pressurize the liquid refrigerant. The first flow regulating valve 18 is connected in parallel with the refrigerant pump 15 and is connected between the liquid storage container 14 and the evaporator 11. The first flow regulating valve 18 is used to form a circuit with the refrigerant pump 15 and regulate the pressure of the refrigerant pump 15. Among them, regulating the pressure of the refrigerant pump 15 includes increasing the pressure of the refrigerant pump 15 or reducing the pressure of the refrigerant pump 15. If the pressure of the refrigerant pump 15 is increased, the refrigerant pressurized by the refrigerant pump 15 flows back to the refrigerant pump 15 through the first flow regulating valve 18 and is pressurized again. Through cyclic pressurization, the output pressure of the refrigerant pump 15 is increased. If the pressure of the refrigerant pump 15 is reduced, relative to the current output pressure of the refrigerant pump 15, by adjusting the opening degree of the first flow regulating valve 18, the pressurization amount of the refrigerant pump 15 is reduced to achieve the preset purpose of reducing the pressure of the refrigerant pump 15. Or, by adjusting the opening degree of the first flow regulating valve 18, the bypass function of the first flow regulating valve 18 plays a major role to achieve the preset purpose of reducing the pressure of the refrigerant pump 15.

[0059] The second flow regulating valve 16 includes, but is not limited to, an electronic expansion valve, a solenoid valve, and a throttle valve. In the embodiments of the present application, the second flow regulating valve 16 is a throttle valve. The liquid storage container 14 is mainly used to store the liquid refrigerant in the refrigeration system. In the refrigeration system, the circulation amount of the refrigerant changes according to the change of the refrigeration load. The light output power of the laser is different, and its heat dissipation requirements also vary. When the refrigeration load is large, the liquid refrigerant in the liquid storage container 14 can be supplemented into the refrigeration system; when the refrigeration load is small, the excess liquid refrigerant is stored in the liquid storage container 14, so as to ensure the stable operation of the refrigeration system. In addition, in the refrigerant pump refrigeration mode or the hybrid refrigeration mode, the liquid storage container 14 needs to store a certain amount of liquid refrigerant to avoid cavitation of the refrigerant pump 15.

[0060] Figure 2 It is a flowchart of a control method for a laser cooling system provided by an embodiment of the present invention. Refer to Figure 1 and Figure 2 , the control method of the laser cooling system includes:

[0061] S11. Obtain the evaporation pressure in the evaporator.

[0062] If the evaporation pressure in the evaporator 11 is insufficient, it will affect the refrigeration capacity of the evaporator 11, and then cause the evaporator 11 to be unable to effectively refrigerate the heating device thereon, control the temperature of the heating device within the set range, and then affect the light output quality of the laser.

[0063] S12. According to the evaporation pressure, adjust the opening degree of the first flow regulating valve to regulate the pressure of the refrigerant pump.

[0064] If the evaporation pressure in the evaporator 11 is insufficient, adjust the opening degree of the first flow regulating valve 18. The first flow regulating valve 18 and the refrigerant pump 15 form a bypass circuit. Under the cyclic boosting action of the refrigerant pump 15, the refrigerant pressure at the outlet of the refrigerant pump 15 is increased. Through the combined action of the first flow regulating valve 18 and the refrigerant pump 15, the evaporation pressure in the evaporator 11 is increased, so as to improve the refrigeration capacity of the evaporator 11, and ensure that the evaporation pressure in the evaporator 11 will not be too low to affect the light output quality of the laser, and improve the light output stability of the laser.

[0065] In other embodiments, if the evaporation pressure is greater than the third preset pressure value, adjust the opening degree of the first flow regulating valve 18 to reduce the pressure of the refrigerant pump 15. If the evaporation pressure in the evaporator 11 exceeds the set value, adjust the opening degree of the first flow regulating valve 18 to reduce the refrigeration capacity of the evaporator 11, control the evaporation pressure between the third preset pressure value and the first preset pressure value, and control the heating device of the laser within the temperature range of the preset range, thereby improving the light output stability of the laser.

[0066] In some embodiments, the refrigeration capacity of the evaporator 11 can be reduced by adjusting other devices except the first flow regulating valve 18. For example, the opening degree of the second flow regulating valve 16 is reduced.

[0067] Since heat generation has a greater impact on the light output stability of the laser, that is, the heat generated by the heat generating device cannot be dissipated in time. As long as the heat generated by the heat generating device can be dissipated in time, it will not have a great impact on the light output stability of the laser. Thus, in other embodiments, if the evaporation pressure is greater than the first preset pressure value, the current opening degree of the first flow regulating valve 18 can meet the requirements of the evaporation pressure, and thus the current opening degree of the first flow regulating valve 18 is maintained. That is, as long as the evaporation pressure is controlled to be greater than the first preset pressure value. It is not necessary to control the evaporation pressure between the third preset pressure value and the first preset pressure value. Thus, the difficulty of system control is reduced.

[0068] Figure 3 It is a flowchart of a control method for a laser cooling system provided by an embodiment of the present invention. Refer to Figure 1 and Figure 3 , the control method of the laser cooling system includes:

[0069] S21. Obtain the evaporation pressure in the evaporator.

[0070] If the opening degree of the first flow regulating valve is less than the first opening degree threshold, step S22 is executed; if the opening degree of the first flow regulating valve is greater than or equal to the first opening degree threshold, step S23 is executed.

[0071] S22. If the opening degree of the first flow regulating valve is less than the first opening degree threshold, increase the opening degree of the first flow regulating valve to boost the refrigerant pump.

[0072] In this step, if the opening degree of the first flow regulating valve 18 is less than the first opening degree threshold, the greater the opening degree of the first flow regulating valve 18, the greater the boosting effect of the circulation loop composed of the first flow regulating valve 18 and the refrigerant pump 15 on the refrigerant pump 15, and the greater the evaporation pressure. The smaller the opening degree of the first flow regulating valve 18, the smaller the boosting effect of the circulation loop composed of the first flow regulating valve 18 and the refrigerant pump 15 on the refrigerant pump 15, and the smaller the evaporation pressure.

[0073] S23. If the opening degree of the first flow regulating valve is greater than or equal to the first opening degree threshold, decrease the opening degree of the first flow regulating valve to boost the refrigerant pump.

[0074] In this step, if the opening degree of the first flow regulating valve 18 is greater than or equal to the first opening threshold, since the first flow regulating valve 18 is in parallel with the refrigerant pump 15, the bypass function of the first flow regulating valve 18 plays a major role. The greater the opening degree of the first flow regulating valve 18, the smaller the boosting effect on the refrigerant pump 15 and the smaller the evaporation pressure. The smaller the opening degree of the first flow regulating valve 18, the greater the boosting effect on the refrigerant pump 15 and the greater the evaporation pressure will be.

[0075] Exemplarily, the first opening threshold is jointly determined by the rated pressure of the refrigerant pump 15 and the diameter of the first flow regulating valve 18. Specifically, first determine the rated pressure of the refrigerant pump 15; the opening degree of the first flow regulating valve 18 is related to the pressure that the refrigerant pump 15 itself can provide. Taking the rated pressure that the refrigerant pump 15 can provide as a reference, determine the first opening threshold according to the actual change of the evaporation pressure in the refrigeration system.

[0076] In one example, the first opening threshold is 35%.

[0077] In one implementation manner, if the opening degree of the first flow regulating valve 18 is less than 35%, increase the opening degree of the first flow regulating valve 18 to boost the refrigerant pump 15. If the opening degree of the first flow regulating valve 18 is greater than or equal to 35%, decrease the opening degree of the first flow regulating valve 18 to boost the refrigerant pump 15.

[0078] In another implementation manner, further, a more refined adjustment method can be set: if the opening degree of the first flow regulating valve 18 is less than the first opening threshold and greater than the second opening threshold, increase the opening degree of the first flow regulating valve 18 to boost the refrigerant pump 15. For example, the first opening threshold is 35% and the second opening threshold is 10%. If the opening degree of the first flow regulating valve 18 is greater than or equal to the first opening threshold and less than the third opening threshold, decrease the opening degree of the first flow regulating valve 18 to boost the refrigerant pump 15. For example, the first opening threshold is 35% and the third opening threshold is 50%.

[0079] Figure 4 For another flowchart of the control method of the laser cooling system provided by the embodiment of the present invention, refer to Figure 1 and Figure 4 , the control method of the laser cooling system includes:

[0080] S101. Obtain the evaporation pressure in the evaporator.

[0081] S102. Determine whether the evaporation pressure is greater than the first preset pressure value.

[0082] S103. If the evaporation pressure is less than or equal to the first preset pressure value, adjust the opening degree of the first flow regulating valve to boost the refrigerant pump.

[0083] Figure 5 This is a flowchart of another control method for a laser cooling system provided by an embodiment of the present invention. Refer to Figure 1 and Figure 5 , the control method of the laser cooling system includes:

[0084] S201. Set the opening degree of the first flow regulating valve according to the light output power of the laser.

[0085] The higher the light output power of the laser, the faster the temperature of the heating device in the laser rises. Correspondingly, the evaporator 11 needs to have a stronger heat dissipation capacity. The lower the light output power of the laser, the slower the temperature rise rate of the heating device in the laser. Correspondingly, the evaporator 11 requires less cooling capacity. Therefore, the opening degree of the first flow regulating valve 18 is set according to the light output power of the laser. It should be noted that the initial opening degree of the first flow regulating valve 18 is set according to the light output power of the laser. That is to say, a preset opening degree is set for the first flow regulating valve 18, and the preset opening degree is set according to the light output power of the laser.

[0086] S202. Obtain the evaporation pressure in the evaporator.

[0087] S203. Determine whether the evaporation pressure is greater than the first preset pressure value.

[0088] If the evaporation pressure is less than or equal to the first preset pressure value, execute step S204; if the evaporation pressure is greater than the first preset pressure value, execute step S205.

[0089] S204. If the evaporation pressure is less than or equal to the first preset pressure value, adjust the opening degree of the first flow regulating valve and boost the refrigerant pump.

[0090] S205. If the evaporation pressure is greater than the first preset pressure value, maintain the opening degree of the first flow regulating valve.

[0091] In this step, if the evaporation pressure is greater than the first preset pressure value, the current opening degree of the first flow regulating valve 18 can meet the requirements of the evaporation pressure, so the current opening degree of the first flow regulating valve 18 is maintained.

[0092] Optionally, the step of setting the opening degree of the first flow regulating valve 18 according to the light output power of the laser includes the following two cases:

[0093] In the first case, if the opening degree of the first flow regulating valve 18 is less than the first opening degree threshold: if the output optical power is less than the first threshold, the opening degree of the first flow regulating valve 18 is within the first opening degree range; if the output optical power is greater than or equal to the first threshold and less than the second threshold, the opening degree of the first flow regulating valve 18 is within the second opening degree range; the values in the second opening degree range are greater than the values in the first opening degree range; the first threshold is less than the second threshold; if the output optical power is greater than or equal to the second threshold, the opening degree of the first flow regulating valve 18 is within the third opening degree range; the values in the third opening degree range are greater than the values in the second opening degree range.

[0094] Exemplarily, the first threshold is 30% and the second threshold is 70%. In other embodiments, further, a more refined adjustment method can be set: if the opening degree of the first flow regulating valve 18 is less than the first opening degree threshold and the output optical power is less than the first threshold and greater than or equal to the third threshold, the opening degree of the first flow regulating valve 18 is within the first opening degree range. For example, the third threshold is 10%.

[0095] Exemplarily, the first opening degree range is 10% - 15%, the second opening degree range is 15% - 30%, and the third opening degree range is 30% - 35%.

[0096] In the second case, if the opening degree of the first flow regulating valve 18 is greater than or equal to the first opening degree threshold: if the output optical power is less than the first threshold, the opening degree of the first flow regulating valve 18 is within the fourth opening degree range, and the values in the fourth opening degree range are greater than the values in the third opening degree range; if the output optical power is greater than or equal to the first threshold and less than the second threshold, the opening degree of the first flow regulating valve 18 is within the fifth opening degree range; the values in the fifth opening degree range are greater than the values in the third opening degree range and less than the values in the fourth opening degree range; if the output optical power is greater than or equal to the second threshold, the opening degree of the first flow regulating valve 18 is within the sixth opening degree range; the values in the sixth opening degree range are greater than the values in the third opening degree range and less than the values in the fifth opening degree range.

[0097] Exemplarily, the fourth opening degree range is 45% - 50%, the fifth opening degree range is 40% - 45%, and the sixth opening degree range is 35% - 40%.

[0098] Figure 6 For the control method flowchart of another laser cooling system provided by the embodiments of the present invention, refer to Figure 1 and Figure 6, the cooling system further includes a condenser 13 and a compressor 12. The compressor 12 is connected between the condenser 13 and the evaporator 11, and the condenser 13 is connected between the compressor 12 and the liquid storage container 14. The gaseous refrigerant enters the compressor 12, and the gaseous refrigerant formed after compression enters the condenser 13 for heat exchange to form a liquid refrigerant. The cooling system further includes a blower, and the blower provides air volume for heat dissipation of the condenser 13. The control method of the laser cooling system includes:

[0099] S301. Obtain the condensation pressure at the outlet of the condenser and the light output power of the laser.

[0100] In some embodiments, the condensation pressure at the outlet of the condenser 13 and the light output power of the laser can also be obtained in two different steps respectively. The step of obtaining the light output power of the laser only needs to be before "setting the opening degree of the first flow regulating valve according to the light output power of the laser".

[0101] Among them, the condensation pressure at the outlet of the condenser 13 refers to the pressure of the liquid refrigerant after condensation by the condenser 13.

[0102] S302. Determine whether the condensation pressure is greater than the second preset pressure value.

[0103] In the case where the condensation pressure is very low, even with the pressurization of the refrigerant pump 15, the evaporation pressure will also be on the low side. Therefore, the condensation pressure can also be detected.

[0104] S303. If the condensation pressure is less than or equal to the second preset pressure value, obtain the rotational speed of the blower and the rotational speed of the refrigerant pump.

[0105] S304. Determine whether the blower stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed.

[0106] The blower stops rotating means that the rotational speed of the blower is 0. The rotational speed of the refrigerant pump 15 reaches the maximum rotational speed, that is, the rotational speed of the refrigerant pump 15 reaches the set highest rotational speed.

[0107] If the blower stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed, execute step S305; if the blower does not stop rotating and the rotational speed of the refrigerant pump does not reach the maximum rotational speed, execute step S306.

[0108] S305. If the blower stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed, set the opening degree of the first flow regulating valve according to the light output power of the laser.

[0109] If the fan stops rotating and the rotational speed of the refrigerant pump 15 reaches the maximum rotational speed, it is impossible to increase the condensation pressure at the outlet of the condenser 13 by adjusting the rotational speed of the fan and the rotational speed of the refrigerant pump 15. Further, the evaporation pressure in the evaporator 11 can be increased by opening the first flow regulating valve 18 and through the combined action of the first flow regulating valve 18 and the refrigerant pump 15.

[0110] S306. If the fan has not stopped rotating and the rotational speed of the refrigerant pump has not reached the maximum rotational speed, reduce the rotational speed of the fan and increase the rotational speed of the refrigerant pump.

[0111] If the fan has not stopped rotating and the rotational speed of the refrigerant pump 15 has not reached the maximum rotational speed, reduce the rotational speed of the fan, thereby increasing the condensation pressure at the outlet of the condenser 13, and increase the rotational speed of the refrigerant pump 15, thereby increasing the evaporation pressure in the evaporator 11.

[0112] In one embodiment, the step of reducing the rotational speed of the fan and the step of increasing the rotational speed of the refrigerant pump can be carried out simultaneously. In another embodiment, the step of reducing the rotational speed of the fan and the step of increasing the rotational speed of the refrigerant pump can be carried out successively at different times.

[0113] Figure 7 For the flowchart of the control method of another laser cooling system provided by the embodiment of the present invention, refer to Figure 1 and Figure 7 , the control method of the laser cooling system includes:

[0114] S401. Obtain the condensation pressure at the outlet of the condenser and the light output power of the laser.

[0115] S402. Judge whether the condensation pressure is greater than the second preset pressure value.

[0116] S403. If the condensation pressure is less than or equal to the second preset pressure value, obtain the rotational speed of the refrigerant pump.

[0117] S404. Judge whether the rotational speed of the refrigerant pump has reached the maximum rotational speed.

[0118] If the rotational speed of the refrigerant pump reaches the maximum rotational speed, execute step S405; if the rotational speed of the refrigerant pump has not reached the maximum rotational speed, execute step S406.

[0119] S405. If the rotational speed of the refrigerant pump reaches the maximum rotational speed, set the opening degree of the first flow regulating valve according to the light output power of the laser.

[0120] S406. If the rotational speed of the refrigerant pump has not reached the maximum rotational speed, increase the rotational speed of the refrigerant pump.

[0121] In an embodiment of the present invention, if the evaporation pressure in the evaporator 11 is relatively low, the rotational speed of the refrigerant pump 15 can be increased to increase the condensation pressure at the outlet of the condenser 13, so as to increase the evaporation pressure in the evaporator 11. If the rotational speed of the refrigerant pump 15 reaches the maximum rotational speed and cannot be further increased, the opening degree of the first flow regulating valve 18 is set according to the light output power of the laser. Through the combined action of the first flow regulating valve 18 and the refrigerant pump 15, the evaporation pressure in the evaporator 11 is increased.

[0122] Figure 8 It is a flowchart of another control method for a laser cooling system provided by an embodiment of the present invention. Refer to Figure 1 and Figure 8 , the control method of the laser cooling system includes:

[0123] S501. Obtain the condensation pressure at the outlet of the condenser and the light output power of the laser.

[0124] S502. Determine whether the condensation pressure is greater than a second preset pressure value.

[0125] Exemplarily, if the condensation pressure is less than or equal to the second preset pressure value, step S503 is executed; if the condensation pressure is greater than the second preset pressure value, return to execute step S501.

[0126] S503. If the condensation pressure is less than or equal to the second preset pressure value, obtain the rotational speed of the fan and the rotational speed of the refrigerant pump.

[0127] Among them, the step of obtaining the rotational speed of the fan and the step of obtaining the rotational speed of the refrigerant pump can be carried out simultaneously, or can be carried out separately in sequence.

[0128] S504. Determine whether the rotational speed of the refrigerant pump reaches the maximum rotational speed.

[0129] If the rotational speed of the refrigerant pump reaches the maximum rotational speed, step S505 is executed; if the rotational speed of the refrigerant pump does not reach the maximum rotational speed, step S507 is executed.

[0130] S505. If the rotational speed of the refrigerant pump reaches the maximum rotational speed, determine whether the fan stops rotating.

[0131] If the fan stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed, step S506 is executed; if the fan does not stop rotating, step S508 is executed.

[0132] S506. If the fan stops rotating and the rotational speed of the refrigerant pump reaches the maximum rotational speed, set the opening degree of the first flow regulating valve according to the light output power of the laser.

[0133] S507. If the rotational speed of the refrigerant pump does not reach the maximum rotational speed, increase the rotational speed of the refrigerant pump.

[0134] S508. If the fan has not stopped rotating, reduce the speed of the fan.

[0135] In the embodiment of the present invention, if the evaporation pressure in the evaporator 11 is relatively low, the rotational speed of the refrigerant pump 15 can be increased first to increase the condensation pressure at the outlet of the condenser 13, so as to increase the evaporation pressure in the evaporator 11. If the rotational speed of the refrigerant pump 15 reaches the maximum rotational speed and cannot be further increased, the rotational speed of the fan is reduced to increase the condensation pressure at the outlet of the condenser 13, so as to increase the evaporation pressure in the evaporator 11. If the rotational speed of the fan is the lowest and cannot be further reduced, the opening degree of the first flow regulating valve 18 is set according to the light output power of the laser. Through the combined action of the first flow regulating valve 18 and the refrigerant pump 15, the evaporation pressure in the evaporator 11 is increased.

[0136] Figure 9 It is a flowchart of another control method for the laser cooling system provided by the embodiment of the present invention. Refer to Figure 1 and Figure 9 , before obtaining the evaporation pressure in the evaporator, the control method of the laser cooling system further includes:

[0137] S601. Obtain the ambient temperature.

[0138] S602. Determine whether the ambient temperature is less than a preset temperature value.

[0139] Exemplarily, the preset temperature value is 0°C. In other embodiments, the preset temperature value can also be 5°C or -5°C.

[0140] S603. If the ambient temperature is less than the preset temperature value, control the refrigeration mode of the cooling system to include the refrigerant pump refrigeration mode. In the refrigerant pump refrigeration mode, the refrigerant pump provides refrigeration.

[0141] In a low-temperature environment, the refrigeration mode of the cooling system is the refrigerant pump refrigeration mode. In the refrigerant pump refrigeration mode, the refrigerant pump 15 provides refrigeration. The compressor 12 stops, and the first flow regulating valve 18 can adjust the opening degree or close according to the specific situation. Through the combined action of the first flow regulating valve 18 and the refrigerant pump 15, the evaporation pressure in the evaporator 11 is increased.

[0142] It should be noted that if the laser emits light and operates at a low ambient temperature, the second flow regulating valve 16 is fully opened or has a relatively large opening degree. In the refrigerant pump refrigeration mode, it is usually not necessary to adjust the opening degree of the second flow regulating valve 16 anymore.

[0143] Figure 10 It is a flowchart of another control method for the laser cooling system provided by the embodiment of the present invention. Refer to Figure 1 and Figure 10, the control method of the laser cooling system includes:

[0144] Collect the condensation pressure and the light output power.

[0145] Judge whether the condensation pressure is greater than P 2 . Wherein, P 2 is the second preset pressure value.

[0146] If not, the condensation pressure is less than or equal to P 2 , collect the rotation speed of the fan and the rotation speed of the refrigerant pump.

[0147] If so, the condensation pressure is greater than P 2 , after a 15s delay, repeat the above steps of collecting the condensation pressure and the light output power.

[0148] Judge whether the fan stops rotating and the rotation speed of the refrigerant pump reaches the maximum rotation speed.

[0149] If so, the fan stops rotating and the rotation speed of the refrigerant pump reaches the maximum rotation speed, and set the opening degree of the first flow regulating valve according to the light output power.

[0150] If not, the fan does not stop rotating and the rotation speed of the refrigerant pump does not reach the maximum rotation speed, reduce the rotation speed of the fan and increase the rotation speed of the refrigerant pump. And repeat the above steps of collecting the condensation pressure and the light output power.

[0151] Obtain the evaporation pressure.

[0152] Judge whether the evaporation pressure is greater than P 1 . Wherein, P 1 is the first preset pressure value.

[0153] If not, the evaporation pressure is less than or equal to P 1 , the opening degree of the first flow regulating valve is reduced by 2%. For example, from the original opening degree of 43%, it is reduced by 2% to 41%. In other embodiments, the value by which the opening degree of the first flow regulating valve is reduced can also be other values other than 2%. And after a 15s delay, repeat the above step of obtaining the evaporation pressure. It should be noted that in this step, taking the opening degree of the first flow regulating valve 18 being greater than or equal to the first opening threshold and reducing the opening degree of the first flow regulating valve to boost the refrigerant pump as an example. In other embodiments, if the opening degree of the first flow regulating valve 18 is less than the first opening threshold, then in response to the evaporation pressure being less than or equal to P 1 , the opening degree of the first flow regulating valve 18 is increased by a value, for example, increased by 2%.

[0154] If so, the evaporation pressure is greater than P 1 , the first flow regulating valve maintains the current opening degree. And after a 15s delay, repeat the above step of obtaining the evaporation pressure.

[0155] An embodiment of the present invention provides a cooling system. Refer to Figure 1 . The cooling system further includes a refrigerant pump 15, a check valve 17, and a first flow regulating valve 18. The refrigerant pump 15 is connected between the liquid storage container 14 and the evaporator 11, and the refrigerant pump 15 is used to pressurize the liquid refrigerant. The check valve 17 is connected in parallel with the compressor 12, and the check valve 17 is connected between the evaporator 11 and the condenser 13. The first flow regulating valve 18 is connected in parallel with the refrigerant pump 15. The first flow regulating valve 18 is connected between the liquid storage container 14 and the second flow regulating valve 16. The first flow regulating valve 18 is used to form a circuit with the refrigerant pump 15 and regulate the pressure of the refrigerant pump 15.

[0156] The cooling system provided by the embodiment of the present invention includes a refrigerant pump 15 and a compressor 12, and provides refrigeration through the refrigerant pump 15 and / or the compressor 12. The cooling system determines different multiple refrigeration modes according to the ambient temperature and the working state of the laser. The multiple refrigeration modes include but are not limited to a hybrid refrigeration mode, a compression refrigeration mode, and a refrigerant pump refrigeration mode. The cooling system can meet the refrigeration requirements of the laser at high temperature, normal temperature, and low temperature, and particularly solves the heat dissipation problem of the laser at low temperature. The cooling system further includes a first flow regulating valve 18, and the first flow regulating valve 18 is connected in parallel with the refrigerant pump 15, so that the first flow regulating valve 18 and the refrigerant pump 15 form a bypass circuit. Under the cyclic boosting action of the refrigerant pump 15, the refrigerant pressure at the outlet of the refrigerant pump 15 is increased. Through the combined action of the first flow regulating valve 18 and the refrigerant pump 15, the evaporation pressure in the evaporator 11 is increased, so as to improve the refrigeration capacity of the evaporator 11, and ensure that the evaporation pressure in the evaporator 11 is not too low to affect the light output quality of the laser, thereby improving the light output stability of the laser. And / or, if the evaporation pressure is greater than the third preset pressure value, the opening degree of the first flow regulating valve 18 is adjusted to reduce the pressure of the refrigerant pump 15, and the evaporation pressure is controlled between the third preset pressure value and the first preset pressure value, and the heating device of the laser is controlled within the preset temperature range, thereby improving the light output stability of the laser.

[0157] Optionally, the cooling system further includes a fan ( Figure 1 not shown in ), and the fan provides air volume for heat dissipation of the condenser 13. If the evaporation pressure in the evaporator 11 is relatively low, the rotational speed of the fan can be reduced to increase the condensation pressure at the outlet of the condenser 13, so as to increase the evaporation pressure in the evaporator 11.

[0158] An embodiment of the present invention provides a laser, which includes the cooling system provided by the above embodiment and an optical device. Since the laser includes the cooling system provided by the above embodiment, the laser has the same or corresponding technical effects as the cooling system.

[0159] Exemplarily, refer to Figure 1, The refrigerant directly undergoes phase change evaporation heat exchange in the evaporator 11 to cool the pump source and fiber optic devices. The laser has three states: shutdown, standby (only the cooling system operates), and lasing. In standby, the cooling system pre-cools the optical devices including the pump source and fiber optic devices; during lasing, the laser emits light, and at this time the cooling system cools the optical devices including the pump source and fiber optic devices to maintain their temperatures within a certain range.

[0160] The operation of the cooling system includes three modes: the compression refrigeration mode, the hybrid refrigeration mode, and the refrigerant pump refrigeration mode. In the compression refrigeration mode, the refrigerant pump 15 stops and the first flow regulating valve 18 is fully open; the refrigerant is compressed by the compressor 12, then comes to the condenser 13 for condensation, and after passing through the liquid storage container 14 and the first flow regulating valve 18, under the action of the second flow regulating valve 16, the refrigerant evaporates and exchanges heat in the evaporator 11 and then returns to the compressor 12. In the refrigerant pump refrigeration mode, the compressor 12 stops, and the first flow regulating valve 18 can be adjusted in opening or closed according to specific conditions; the refrigerant after heat exchange in the evaporator 11 passes through the check valve 17 and comes to the condenser 13 for condensation, and then through the liquid storage container 14 and the refrigerant pump 15, and under the action of the second flow regulating valve 16, the refrigerant evaporates and exchanges heat in the evaporator 11. In the hybrid refrigeration mode, the first flow regulating valve 18 is fully closed; the refrigerant after heat exchange in the evaporator 11 is compressed by the compressor 12, then comes to the condenser 13 for condensation, and then through the liquid storage container 14 and the refrigerant pump 15, and under the action of the second flow regulating valve 16, the refrigerant evaporates and exchanges heat in the evaporator 11.

[0161] Exemplarily, the cooling system determines different multiple refrigeration modes according to the ambient temperature and the working state of the laser. If the ambient temperature is high and the refrigeration demand of the laser is large, the refrigeration mode can include the compression refrigeration mode. If the ambient temperature is normal and the refrigeration demand of the laser is medium, the refrigeration mode can include the hybrid refrigeration mode or the refrigerant pump refrigeration mode. If the ambient temperature is low and the refrigeration demand of the laser is small, the refrigeration mode can include the refrigerant pump refrigeration mode.

[0162] The embodiment of the present invention provides a laser processing device, and the laser processing device includes the laser in the above embodiment. A laser beam is output from the laser processing device to the surface of the workpiece to achieve the processing of the workpiece. Since the laser processing device includes the laser in the above embodiment, and the laser includes the cooling system in the above embodiment, the laser processing device has the same or corresponding technical effects as the cooling system.

[0163] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments, combinations with each other, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A control method for a laser cooling system, characterized in that: The cooling system comprises an evaporator, a liquid storage container, a refrigerant pump and a first flow regulating valve, wherein the evaporator is used to cool the heating device of the laser, the liquid storage container is used to store liquid refrigerant, the refrigerant pump is connected between the liquid storage container and the evaporator, the first flow regulating valve is connected in parallel with the refrigerant pump, and the first flow regulating valve is used to form a loop with the refrigerant pump and regulate the pressure of the refrigerant pump; The control method comprises: obtaining the evaporation pressure in the evaporator; According to the evaporation pressure, the opening of the first flow regulating valve is adjusted to adjust the pressure of the refrigerant pump.

2. The control method according to claim 1, characterized in that: Adjusting the opening of the first flow regulating valve to adjust the pressure of the refrigerant pump includes: If the opening of the first flow regulating valve is less than a first opening threshold, increase the opening of the first flow regulating valve to increase the pressure of the refrigerant pump; and / or, if the opening of the first flow regulating valve is greater than or equal to the first opening threshold, reduce the opening of the first flow regulating valve to increase the pressure of the refrigerant pump.

3. The control method according to claim 2, characterized in that: Before obtaining the evaporation pressure in the evaporator, the method further includes: The opening of the first flow regulating valve is set according to the output light power of the laser.

4. The control method according to claim 3, characterized in that: According to the output light power of the laser, the opening of the first flow regulating valve is set, including: If the opening of the first flow regulating valve is less than the first opening threshold: if the output light power is less than the first threshold, the opening of the first flow regulating valve is in the first opening range; if the output light power is greater than or equal to the first threshold and less than the second threshold, the opening of the first flow regulating valve is in the second opening range; the value in the second opening range is greater than the value in the first opening range; the first threshold is less than the second threshold; if the output light power is greater than or equal to the second threshold, the opening of the first flow regulating valve is in the third opening range; the value in the third opening range is greater than the value in the second opening range; If the opening of the first flow regulating valve is greater than or equal to the first opening threshold: if the light output power is less than the first threshold, the opening of the first flow regulating valve is located in the fourth opening range, and the value in the fourth opening range is greater than the value in the third opening range; if the light output power is greater than or equal to the first threshold, and less than the second threshold, the opening of the first flow regulating valve is located in the fifth opening range; the value in the fifth opening range is greater than the value in the third opening range, and less than the value in the fourth opening range; if the light output power is greater than or equal to the second threshold, the opening of the first flow regulating valve is located in the sixth opening range; the value in the sixth opening range is greater than the value in the third opening range, and less than the value in the fifth opening range.

5. The control method according to claim 3, characterized in that: The cooling system further comprises a condenser and a compressor, wherein the compressor is connected between the condenser and the evaporator, and the condenser is connected between the compressor and the liquid storage container, and the gaseous refrigerant enters the compressor, and the gaseous refrigerant formed after compression enters the condenser for heat exchange to form liquid refrigerant; Before setting the opening of the first flow regulating valve according to the output light power of the laser, the method further includes: Obtaining the rotation speed of the refrigerant pump; The step of setting the opening of the first flow regulating valve according to the output light power of the laser comprises: If the speed of the refrigerant pump reaches the maximum speed, the opening of the first flow regulating valve is set according to the output power of the laser; After obtaining the rotation speed of the refrigerant pump, the method further includes: If the rotation speed of the refrigerant pump has not reached the maximum rotation speed, the rotation speed of the refrigerant pump is increased.

6. The control method according to claim 5, characterized in that: The cooling system also includes a fan, which provides air volume and heat dissipation for the condenser; Before setting the opening of the first flow regulating valve according to the output light power of the laser, the method further includes: Obtaining the rotation speed of the fan; The step of setting the opening of the first flow regulating valve according to the output light power of the laser comprises: If the fan stops rotating and the speed of the refrigerant pump reaches the maximum speed, the opening of the first flow regulating valve is set according to the output power of the laser; After obtaining the rotation speed of the fan, the method further includes: If the fan does not stop rotating, reduce the rotation speed of the fan.

7. The control method according to claim 5, characterized in that: Before obtaining the rotation speed of the refrigerant pump, the method further includes: Obtaining the condensation pressure at the outlet of the condenser and the optical output power of the laser; Wherein, the step of obtaining the rotation speed of the refrigerant pump comprises: If the condensing pressure is less than or equal to the second preset pressure value, the rotation speed of the refrigerant pump is obtained.

8. The control method according to claim 1, characterized in that: Before obtaining the evaporation pressure in the evaporator, the method further includes: Get the ambient temperature; If the ambient temperature is less than a preset temperature value, controlling the cooling system to adopt a refrigeration mode including a refrigerant pump refrigeration mode, in which a refrigerant pump provides refrigeration.

9. A cooling system for a laser, characterized in that: The cooling system comprises an evaporator, a condenser, a liquid storage container and a second flow regulating valve connected in sequence; the cooling system also comprises a compressor connected between the evaporator and the condenser; The evaporator is used to cool the heating device of the laser; the gaseous refrigerant enters the compressor, and the gaseous refrigerant formed after compression enters the condenser for heat exchange to form liquid refrigerant; the liquid storage container is used to store the liquid refrigerant; The cooling system further includes a refrigerant pump, a one-way valve and a first flow regulating valve; the refrigerant pump is connected between the liquid storage container and the evaporator and is used to pressurize the liquid refrigerant; The one-way valve is connected in parallel with the compressor, and the first flow regulating valve is connected in parallel with the refrigerant pump. The first flow regulating valve is used to form a loop with the refrigerant pump and regulate the pressure of the refrigerant pump.

10. The cooling system according to claim 9, characterized in that The cooling system also includes a fan, which provides air volume for heat dissipation of the condenser.

11. A laser, characterized in that: Comprising the cooling system according to claim 9 or 10; and an optical device.

12. A laser processing device, characterized in that: Comprising the laser as claimed in claim 11.

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