High-precision laser cooling-water machine and temperature control method thereof

Abstract

The invention discloses a high-precision laser water chiller and a temperature control method thereof, and solves the problems of high cost and low control precision of a laser water chiller in the prior art, the high-precision laser water chiller comprises a low-temperature circulation loop and a high-temperature circulation loop, the high-temperature circulation loop comprises a first electromagnetic valve connected with a compressor, the first electromagnetic valve is connected with a first capillary tube, and the first capillary tube is connected with a second capillary tube; the low-temperature circulation loop comprises a second capillary tube, a second electromagnetic valve is connected to the second capillary tube in parallel, one end of the second capillary tube is connected with the condenser, the other end of the second capillary tube is connected with the heat exchange loop, and the first electromagnetic valve and the second electromagnetic valve are connected with the control panel. The control panel controls the heat exchange amount by controlling opening and closing of the first electromagnetic valve and the second electromagnetic valve. The two loops are used for adjusting the heat exchange amount of the heat exchange loop, so that the temperature control precision of the laser water chiller is improved, meanwhile, the capillary tube and the electromagnetic valve are used for replacing an electronic expansion valve, the control circuit is simple, the error rate is low, and cost is saved.

Description

Technical Field

[0001] The invention relates to the technical field of water chillers, and in particular to a high-precision laser water chiller and a temperature control method thereof. Background Art

[0002] Lasers have important applications in biomedicine, industry, and scientific research. Their ultrashort pulse width and high peak power enable picosecond lasers to be used in biological microscopic imaging, optical parametric oscillation, drilling, cutting, and other micro-processing processes. A large amount of heat is generated during the operation of the laser, and its stability is closely related to the temperature stability of the core parts. Laser chillers are used to provide circulating cooling water with a constant temperature to the laser to maintain the high-precision operation of the laser. For example, high-precision laser chillers used for picosecond, femtosecond, nanosecond and other ultrafast lasers usually require a temperature control accuracy of ±0.1°C.

[0003] Conventional laser chillers generally adopt a single cooling circuit. The refrigerant enters the evaporator through the condenser, and the cooling water temperature is controlled by controlling the flow rate according to the solenoid valve between the condenser and the evaporator. However, on the one hand, the electronic expansion valve is relatively expensive, and the control system for adjusting the opening of the electronic expansion valve is relatively complex, with many components, high prices and high costs. On the other hand, the control is only controlled through one cooling circuit, the control accuracy is low, and the electronic expansion valve control system is complex and has a high error rate, which cannot guarantee the temperature control accuracy of the laser chiller. Summary of the invention

[0004] The purpose of the present invention is to overcome the problems of high temperature control cost and low control accuracy of laser water chillers in the prior art, and provide a high-precision laser water chiller and a temperature control method thereof, wherein a low-temperature circulation loop and a high-temperature circulation loop are arranged, and the heat exchange capacity of the heat exchange loop is adjusted by using the two loops, thereby improving the temperature control accuracy of the laser water chiller and maintaining the temperature stability of the laser water chiller. At the same time, a capillary tube and a solenoid valve are used instead of an electronic expansion valve, so the control circuit is simple and the error rate is low, which further improves the temperature control accuracy of the laser water chiller while saving costs.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A high-precision laser chiller comprises: a low-temperature circulation loop and a high-temperature circulation loop, the high-temperature circulation loop comprises a first solenoid valve connected to a compressor, the first solenoid valve is connected to a first capillary, the first capillary is connected to a heat exchange loop, the low-temperature circulation loop comprises a second capillary, a second solenoid valve is connected in parallel to the second capillary, one end of the second capillary is connected to a condenser, and the other end of the second capillary is connected to the heat exchange loop, the first solenoid valve and the second solenoid valve are connected to a control board, and the control board controls the heat exchange amount by controlling the opening and closing of the first solenoid valve and the second solenoid valve.

[0006] In the present invention, after the refrigerant is discharged from the compressor, it is divided into two paths. One path is throttled from the condenser, the second solenoid valve, and the second capillary tube to become a low-temperature liquid, and then enters the heat exchange circuit for heat exchange; the other path is converted into a high-temperature gas or liquid through the first solenoid valve and the first capillary tube, and then enters the heat exchange circuit for heat exchange. By opening / closing the first solenoid valve and the second solenoid valve, the heat exchange amount of the evaporator is adjusted to maintain the temperature stability of the laser chiller.

[0007] Preferably, when the first solenoid valve and the second solenoid valve are closed, the heat exchange rate of the heat exchange circuit is 100%; when the first solenoid valve is closed, the second solenoid valve is opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 75-100%; when the first solenoid valve and the second solenoid valve are both opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 50-75%; when the first solenoid valve is opened, the second solenoid valve is opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 25-50%; when the first solenoid valve and the second solenoid valve are both opened, the heat exchange rate of the heat exchange circuit is 0-25%.

[0008] Preferably, the heat exchange circuit comprises a water tank and an evaporator, the water tank outlet is connected to the evaporator water inlet, the water tank inlet is connected to a customer device, and the customer device is connected to the evaporator water outlet.

[0009] Preferably, a heating component is provided in the water tank, and the heating component is connected to a control panel. The control panel controls the start-up of the heating component according to the water temperature in the water tank and adjusts the temperature control accuracy.

[0010] Preferably, a water pump is provided between the outlet of the water tank and the water inlet of the evaporator, and a spiral water outlet pipe is provided between the water outlet of the water tank and the water inlet of the water pump.

[0011] Preferably, a drying filter is provided between the gas outlet of the condenser and the second capillary tube.

[0012] Preferably, a fan is installed on the condenser.

[0013] A high-precision laser chiller control method, comprising: The water temperature at the evaporator outlet is obtained. If the water temperature is less than a first temperature threshold, the first solenoid valve is closed, and the second solenoid valve is opened and closed at a preset frequency. The water temperature at the evaporator outlet is obtained. If the water temperature is still lower than the first temperature threshold, the first solenoid valve and the second solenoid valve are both opened and closed at a preset frequency. The water temperature at the evaporator outlet is obtained. If the water temperature is less than a second temperature threshold, the first solenoid valve is opened, and the second solenoid valve is opened and closed at a preset frequency. The water temperature at the evaporator water outlet is obtained. If the water temperature is still lower than the second temperature threshold, both the first solenoid valve and the second solenoid valve are opened.

[0014] Preferably, if the evaporator heat exchange rate is less than or equal to 50% and the water temperature is less than the first temperature threshold, the water in the water tank is heated; if the evaporator water outlet temperature is less than the second threshold, the first solenoid valve is opened and the second solenoid valve is opened and closed regularly according to a preset frequency; if the water temperature is greater than the first threshold and the evaporator heat exchange rate is equal to 100%, the water in the water tank is cooled.

[0015] Preferably, the first temperature threshold is the sum of the required temperature of the evaporator water outlet and the temperature control accuracy; the second temperature threshold is the sum of the required temperature of the evaporator water outlet and the maximum value of the water heating temperature in the water tank.

[0016] Therefore, the present invention has the following beneficial effects: 1. Set up a low-temperature circulation loop and a high-temperature circulation loop. Use the two loops to control the opening and closing of the solenoid valves on the two adjustment loops through the control panel to adjust the heat exchange capacity of the heat exchange loop, thereby adjusting the cooling temperature of the laser chiller. The cooling temperature of the laser chiller can be adjusted in time to improve the temperature control accuracy of the laser chiller.

[0017] 2. Using capillaries and solenoid valves instead of electronic expansion valves has a simple control circuit and a low error rate, which further improves the temperature control accuracy of the laser chiller while saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the principle of the laser chiller in Example 1 of the present invention.

[0019] Figure 2 This is a schematic diagram of the working principle of the current water-cooled chiller.

[0020] Figure 3 This is a schematic diagram of the principle of the laser chiller in the second embodiment of the present invention.

[0021] Figure 4 This is a flow chart of the steps of the high-precision laser chiller temperature control method in the third embodiment.

[0022] In the figure: 1. compressor; 2. condenser; 3. first solenoid valve; 4. first capillary tube; 5. drying filter; 6. second solenoid valve; 7. second capillary tube; 8. evaporator; 9. water pump; 10. water tank; 11. customer equipment; 12. heating component; 13. fan; 14. electronic expansion valve. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments: Embodiment 1: This embodiment provides a high-precision laser water chiller, which uses two circuits to adjust the heat exchange capacity of the heat exchange circuit, thereby improving the temperature control accuracy of the laser water chiller and maintaining the temperature stability of the laser water chiller.

[0024] like Figure 1 As shown, it includes a condenser 2, a compressor 1, a first solenoid valve 3, a first capillary tube 4, a second solenoid valve 6, a second capillary tube 7, an evaporator 8, a water pump 9, a water tank 10 and a heating component 12. The compressor outlet is connected to the refrigerant inlet of the condenser, the refrigerant outlet of the condenser is connected to the second capillary tube, the second solenoid valve is connected in parallel with the second capillary tube, the second capillary tube is connected to the air inlet of the evaporator, and the air outlet of the evaporator is connected to the compressor inlet; the water outlet of the evaporator is connected to the customer equipment 11, the customer equipment is connected to the water tank inlet, the water tank outlet is connected to the water pump through a spiral water outlet pipe, and the water pump is connected to the water inlet of the evaporator; the heating component is installed in the water tank.

[0025] Among them, the compressor, condenser, second capillary, second solenoid valve, and evaporator constitute a low-temperature circulation loop, the compressor, first solenoid valve, first capillary, and evaporator constitute a high-temperature circulation loop, and the evaporator, customer equipment, water tank, and water pump constitute a heat exchange loop.

[0026] The first capillary and the second capillary mainly play the role of throttling, reducing pressure and regulating the amount of liquid supply. The first capillary and the second capillary control the flow rate of the refrigerant by increasing the resistance to liquid flow, and reduce pressure during the flow process, turning the high-pressure refrigerant liquid into a low-pressure and high-temperature gas. The throttling process of the capillary is completed along its total length, which will produce a large pressure drop. Its inner diameter, length and inlet and outlet pressure difference will affect the amount of refrigerant passing through and the pressure drop.

[0027] The high-precision laser chiller provided in this embodiment is based on vapor compression refrigeration technology. This process involves four main steps: compression, condensation, throttling and evaporation. The laser chiller compresses the refrigerant into a high-temperature and high-pressure gas through a compressor, and then cools it into a liquid through a condenser. Next, the liquid passes through a capillary tube and becomes a low-temperature and low-pressure wet vapor, absorbing the heat of the cooling water in the evaporator, thereby reducing the water temperature. The evaporated refrigerant is sucked into the compressor again, completing a refrigeration cycle.

[0028] Based on the above, in this embodiment, the working process of the laser chiller includes: During operation, for the low-temperature circulation loop: the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. The high-temperature and high-pressure refrigerant releases heat through the condenser and liquefies into a high-pressure liquid at room temperature. Then, it passes through the first solenoid valve and the first capillary tube and enters the evaporator, absorbs the heat of the heated cooling water in the evaporator, cools the heated cooling water, and then the refrigerant is sucked in and compressed by the compressor, thereby circulating.

[0029] For the high-temperature circulation loop: the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. The high-temperature and high-pressure refrigerant directly passes through the first solenoid valve and the first capillary tube to become a high-temperature gas or liquid and then enters the evaporator, absorbing the heat of the heated cooling water in the evaporator, cooling the heated cooling water, and then the refrigerant is sucked in and compressed by the compressor to circulate.

[0030] For the heat exchange circuit: the high-temperature coolant flowing out from the customer's equipment enters the water tank, passes through the water pump and enters the evaporator. After passing through the evaporator, it is cooled to the temperature required by the customer. The cooled coolant then passes through the customer's equipment again to cool the customer's equipment (such as a laser), maintaining the temperature of the customer's equipment stable so that it can work normally.

[0031] The following further describes the relationship between the evaporator heat exchange amount corresponding to the on and off of the first solenoid valve and the second solenoid valve in the high-precision laser chiller provided in this embodiment.

[0032] The heat exchange capacity of the evaporator refers to the amount of heat exchange generated by the transfer of heat between the evaporating liquid and the air. Specifically, in the process of cooling the air, the evaporator absorbs heat through the evaporation of the liquid, thereby reducing the temperature of the air.

[0033] State 1: The first solenoid valve 1 and the second solenoid valve 2 are closed.

[0034] In this working state, the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. All the refrigerant passes through the condenser and the second capillary tube and enters the evaporator. At this time, the evaporator has 100% heat exchange capacity.

[0035] State 2: The first solenoid valve is closed, and the second solenoid valve is closed and opened at a certain frequency.

[0036] In this working state, the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. After passing through the condenser, the high-temperature and high-pressure refrigerant is divided into two paths, one flowing through the second solenoid valve and the other flowing through the second capillary tube. The refrigerants passing through the second solenoid valve and the second capillary tube converge and enter the evaporator. However, due to the different flow rates of the refrigerant in the second capillary tube and the second solenoid valve, the amount of refrigerant after the diversion and convergence is different from that before the diversion (that is, the amount of refrigerant flowing out of the condenser refrigerant outlet), and the second solenoid valve is opened and closed, so the amount of refrigerant flowing into the evaporator also changes accordingly. At this time, the evaporator has 75-100% heat exchange. The frequency of opening and closing the second solenoid valve is related to the heat exchange. The longer the second solenoid valve is opened, the greater the heat exchange.

[0037] State 3: The first solenoid valve is closed and opened at a certain frequency, and the second solenoid valve is closed and opened at a certain frequency.

[0038] In this working state, the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. After the high-temperature and high-pressure refrigerant flows out of the compressor, it is divided into two paths. One path passes through the first solenoid valve and the first capillary tube to the evaporator, and the other path passes through the condenser and then is divided into two paths, respectively flowing through the second solenoid valve and the second capillary tube. At this time, because the first solenoid valve will be opened on time, part of the refrigerant from the compressor directly passes through the first solenoid valve and the first capillary tube to the evaporator, and is not condensed by the condenser, and the heat exchange is further reduced, and the evaporator has 50-75% heat exchange.

[0039] State 4: The first solenoid valve is open, and the second solenoid valve is closed and opened at a certain frequency.

[0040] In this working state, the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. After the high-temperature and high-pressure refrigerant flows out of the compressor, it is divided into two paths. One path flows to the evaporator through the first solenoid valve and the first capillary tube, and the other path flows through the condenser and then is divided into two paths, respectively flowing through the second solenoid valve and the second capillary tube 2. At this time, because the first solenoid valve is open for a long time, nearly half of the refrigerant from the compressor directly passes through the first solenoid valve and the first capillary tube to the evaporator without being condensed by the condenser, and the heat exchange is further reduced. The evaporator has 25-50% heat exchange; State 5: The first solenoid valve is open, and the second solenoid valve is open.

[0041] In this working state, the compressor compresses the refrigerant gas and outputs high-temperature and high-pressure refrigerant. After the high-temperature and high-pressure refrigerant flows out of the compressor, it is divided into two paths. One path flows to the evaporator through the first solenoid valve and the first capillary tube, and the other path is condensed by the condenser and then divided into two paths, respectively flowing through the second solenoid valve and the second capillary tube 2. At this time, because the first solenoid valve and the second solenoid valve are opened for a long time, nearly half of the refrigerant from the compressor directly passes through the first solenoid valve and the first capillary tube to the evaporator without being condensed by the condenser, and the refrigerant after passing through the condenser will always be divided into two paths, and the heat exchange capacity is reduced again, and the evaporator has a heat exchange capacity of 0-25%.

[0042] The cooling water temperature of the laser chiller is closely related to the heat exchange efficiency of the evaporator. When the cooling water temperature rises, the heat exchange efficiency of the laser chiller will decrease significantly. Therefore, this embodiment adjusts the heat exchange of the evaporator by adjusting the opening and closing of the first solenoid valve and the second solenoid valve, thereby controlling the temperature of the cooling water and cooling the customer's equipment. The control accuracy is high and the control method is simple. When controlling, the heat exchange decreases and the cooling water temperature passing through the evaporator increases; conversely, the heat exchange increases and the cooling water temperature passing through the evaporator decreases.

[0043] On the other hand, the present embodiment also includes a heating component, which is installed in the water tank and is used to heat the cooling water in the water tank. The temperature control accuracy of the chiller can be adjusted by controlling the on and off time of the heating component.

[0044] Specifically: In this embodiment, when state 3 or state 4 is reached, that is, when the evaporator heat exchange rate is 50%±2%, if the cooling temperature of the chiller is still lower than the target temperature required for laser cooling, the heating component is activated to heat the cooling water in the water tank, thereby increasing the cooling temperature of the chiller to reach the target temperature required for laser cooling.

[0045] In other embodiments, a refrigeration component may be installed in the water tank. When the evaporator heat exchange reaches 100%, if the target temperature required for laser cooling still cannot be reached, the refrigeration component may be controlled to cool the cooling water in the water tank.

[0046] In this embodiment, a fan is also included. The fan is installed on the condenser to dissipate the heat in the condenser, so that the high-temperature and high-pressure refrigerant transferred from the compressor can be condensed. The fan can blow the surrounding air to the condenser, increase the heat dissipation area of ​​the condenser, speed up the heat dissipation rate, and thus improve the refrigeration efficiency of the condenser. The fan on the condenser can make the air flow, thereby increasing the heat conduction rate and achieving better heat dissipation effect. The fan on the condenser can improve the heat dissipation efficiency of the condenser, thereby making the refrigeration system run more smoothly and reducing energy waste. It can also enhance heat dissipation and prevent the condenser temperature from rising too quickly, thereby extending the service life of the condenser.

[0047] Based on the above, the high-precision laser chiller provided in this embodiment has the following beneficial effects: 1. Set up a low-temperature circulation loop and a high-temperature circulation loop. Use the two loops to control the opening and closing of the solenoid valves on the two adjustment loops through the control panel to adjust the heat exchange capacity of the heat exchange loop, thereby adjusting the cooling temperature of the laser chiller. The cooling temperature of the laser chiller can be adjusted in time to improve the temperature control accuracy of the laser chiller.

[0048] 2. Using capillaries and solenoid valves instead of electronic expansion valves has a simple control circuit and a low error rate, which further improves the temperature control accuracy of the laser chiller while saving costs.

[0049] Embodiment 2: This embodiment provides a high-precision laser chiller and applies it to specific scenarios.

[0050] like Figure 2As shown, the conventional laser chiller includes a condenser 2, a compressor 1, an electronic expansion valve 14, a filter drier 5, an evaporator 8, a water pump 9, a water tank 10 and a fan 13. The compressor outlet is connected to the refrigerant inlet of the condenser, the refrigerant outlet of the condenser is connected to the filter drier, the filter drier is connected to the electronic expansion valve, the electronic expansion valve is connected to the air inlet of the evaporator, and the air outlet of the evaporator is connected to the compressor inlet; the water outlet of the evaporator is connected to the customer equipment 11, the customer equipment is connected to the water tank inlet, the water tank outlet is connected to the water pump through a spiral water outlet pipe, and the water pump is connected to the water inlet of the evaporator.

[0051] When working, the refrigerant enters the condenser from the compressor outlet, and the condenser condenses the refrigerant. Then, it passes through the drying filter and the electronic expansion valve to become a low-temperature liquid, and then enters the evaporator for heat exchange. By adjusting the opening of the electronic expansion valve, the heat exchange amount of the evaporator is adjusted to maintain the temperature stability of the laser chiller.

[0052] However, there are the following problems: First, the laser chiller requires an electronic expansion valve and the price of the electronic expansion valve is relatively high. Second, the control system for adjusting the opening of the electronic expansion valve is relatively complex, with many components and high prices. In addition, there is only one low-temperature circulation loop, and the accuracy of adjusting the heat exchange of the evaporator is low, and the accuracy of controlling the temperature of the laser chiller is low.

[0053] like Figure 3 As shown, the new chiller provided in this embodiment includes: a condenser 2, a compressor 1, a first solenoid valve 3, a first capillary tube 4, a drying filter 5, a second solenoid valve 6, a second capillary tube 7, an evaporator 8, a water pump 9, a water tank 10 and a fan 13, the compressor outlet is connected to the refrigerant inlet of the condenser, the refrigerant outlet of the condenser is connected to the second capillary tube, the second solenoid valve is connected in parallel with the second capillary tube, the second capillary tube is connected to the air inlet of the evaporator, and the air outlet of the evaporator is connected to the compressor inlet; the water outlet of the evaporator is connected to the customer equipment 11, the customer equipment is connected to the water tank inlet, the water tank outlet is connected to the water pump through a spiral water outlet pipe, and the water pump is connected to the water inlet of the evaporator.

[0054] Among them, the compressor, condenser, drying filter, second capillary, second solenoid valve, and evaporator constitute a low-temperature circulation loop, the compressor, first solenoid valve, first capillary, and evaporator constitute a high-temperature circulation loop, and the evaporator, customer equipment, water tank, and water pump constitute a heat exchange loop.

[0055] The dry filter is used to remove mechanical impurities in the refrigerant to prevent the pipeline from being blocked by impurities, ensuring the normal operation of the laser chiller. It can also absorb moisture in the refrigerant to prevent ice blockage caused by the presence of moisture, ensuring the stable operation of the laser chiller. The dry filter can also protect the compressor, solenoid valves, capillaries and other important components from the influence of impurities and moisture, extending the service life of the laser chiller.

[0056] During operation, the refrigerant is divided into two paths after being discharged from the compressor. One path passes through the condenser, the drying filter, the second solenoid valve, and the second capillary tube to become a low-temperature liquid, and then enters the evaporator for heat exchange; the other path passes through the first solenoid valve and the first capillary tube to become a high-temperature gas or liquid, and then enters the evaporator for heat exchange. The heat exchange amount of the evaporator is adjusted by opening / closing the first solenoid valve 1 and the second solenoid valve to maintain the stability of the system temperature.

[0057] The relationship between the evaporator heat exchange amount corresponding to the on and off of the first solenoid valve and the second solenoid valve is described in detail below.

[0058] State 1: The first solenoid valve and the second solenoid valve are closed.

[0059] In this state, all refrigerants pass through the condenser, filter drier, and second capillary tube, and the evaporator has 100% heat exchange; State 2: The first solenoid valve is closed, and the second solenoid valve is closed and opened at a certain frequency.

[0060] In this state, the refrigerant is divided into two paths after passing through the condenser and the drying filter, flowing through the second solenoid valve and the second capillary tube respectively, and the evaporator has 75-100% heat exchange. At this time, the longer the second solenoid valve is opened, the lower the heat exchange.

[0061] State 3: The first solenoid valve and the second solenoid valve are closed and opened at a certain frequency.

[0062] In this state, the refrigerant flows out of the compressor and is divided into two paths. One path flows to the evaporator through the first solenoid valve and the first capillary tube, and the other path flows through the condenser and the drying filter and then is divided into two paths, respectively flowing through the second solenoid valve and the first capillary tube. The evaporator has 50-75% heat exchange. At this time, the longer the first solenoid valve and the second solenoid valve are opened, the lower the heat exchange.

[0063] State 4: The first solenoid valve is open, and the second solenoid valve is closed and opened at a certain frequency.

[0064] In this state, the refrigerant flows out of the compressor and is divided into two paths. One path passes through the first solenoid valve and the first capillary tube to the evaporator, and the other path passes through the condenser and the drying filter and then is divided into two paths, respectively flowing through the second solenoid valve and the second capillary tube. The evaporator has 25-50% heat exchange. At this time, the longer the second solenoid valve is opened, the lower the heat exchange.

[0065] State 5: Both the first solenoid valve and the solenoid valve 2 are open.

[0066] In this state, the refrigerant flows out of the compressor and is divided into two paths. One path flows through the first solenoid valve and the first capillary tube to the evaporator, and the other path flows through the condenser and the drying filter and then is divided into two paths, respectively flowing through the second solenoid valve and the second capillary tube. At this time, the evaporator has a heat exchange capacity of 0 to 25%.

[0067] The high-precision laser chiller provided in this embodiment controls the temperature of cooling water by controlling the heat exchange of the evaporator. During control, the heat exchange is reduced and the temperature of cooling water passing through the evaporator increases; conversely, the heat exchange is increased and the temperature of cooling water passing through the evaporator decreases.

[0068] Therefore, the high-precision laser chiller provided in this embodiment has the following beneficial effects: 1. Solved the problem of high parts cost of existing laser chiller temperature control solutions, making the product more competitive.

[0069] 2. The problem of complex control circuit of existing laser chiller temperature control solution is solved, and the probability of product error is lower.

[0070] Embodiment three: This embodiment provides a high-precision laser chiller temperature control method, which controls the high-precision laser chiller provided in Embodiment 1 or Embodiment 2. During the laser cutting process, the cooling water of the laser chiller is needed to cool the laser generator of the laser cutting machine to ensure that the laser works stably in a high temperature environment, prevent thermal deformation, and ensure cutting accuracy and equipment life.

[0071] This embodiment provides a temperature control method for a high-precision laser chiller, and the control process is as follows: Step 1: Obtain the water temperature at the evaporator outlet. If the water temperature is less than a first temperature threshold, the first solenoid valve is closed and the second solenoid valve is opened and closed at a preset frequency.

[0072] Under normal circumstances, when it is used at the beginning, the first solenoid valve and the second solenoid valve of the laser chiller are closed. At this time, the evaporator heat exchange rate is equal to 100%. The water temperature at the evaporator outlet is obtained. If the water temperature is greater than the first threshold at this time, the refrigeration component in the water tank is turned on to cool the water in the water tank; if the water temperature is less than the first temperature threshold at this time, the first solenoid valve is closed, and the second solenoid valve is opened and closed at a preset frequency. At this time, the evaporator heat exchange rate is 75-100%, thereby increasing the cooling temperature of the laser chiller (for example, when the heat exchange rate is 100%, the cooling temperature of the laser chiller is 10 degrees Celsius, then after this operation, the cooling temperature of the laser chiller can be increased to greater than 10 degrees Celsius).

[0073] The first temperature threshold is the sum of the required temperature of the evaporator water outlet and the temperature control accuracy.

[0074] Step 2: obtaining the water temperature at the evaporator outlet. If the water temperature is still lower than the first temperature threshold, the first solenoid valve and the second solenoid valve are opened and closed at a preset frequency.

[0075] After the first step is executed, the water temperature of the evaporator outlet is continuously obtained. If the water temperature of the evaporator outlet is still lower than the first temperature threshold, the first solenoid valve and the second solenoid valve are opened and closed at a preset frequency. At this time, the heat exchange amount of the evaporator is 50-75%, further increasing the cooling temperature of the laser chiller.

[0076] Step three, obtaining the water temperature at the evaporator outlet. If the water temperature is less than a second temperature threshold, the first solenoid valve is opened, and the second solenoid valve is opened and closed regularly according to a preset frequency.

[0077] If the evaporator heat exchange capacity is less than or equal to 50% and the water temperature is less than the first temperature threshold, the water in the water tank is heated. If the evaporator outlet temperature is less than the second threshold, the first solenoid valve is opened and the second solenoid valve is opened and closed regularly according to the preset frequency. The second temperature threshold is the sum of the required temperature of the evaporator outlet and the maximum value of the water heating temperature in the water tank. The heating temperature value is the difference between the water temperature after the heating component is heated and the water temperature before the heating component is turned on.

[0078] The maximum value of the water heating temperature in the water tank is determined by the power of the heating component and the set energy consumption of the laser chiller.

[0079] Step 4: Obtain the water temperature at the evaporator outlet. If the water temperature is still lower than the second temperature threshold, both the first solenoid valve and the second solenoid valve are opened.

[0080] By controlling the opening and closing of the first solenoid valve and the second solenoid valve, as well as the opening and closing of the heating component, the cooling temperature of the laser chiller is controlled so that the temperature control accuracy can meet the cooling requirements of the picosecond laser.

[0081] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A high-precision laser chiller, characterized in that: include: A low-temperature circulation loop and a high-temperature circulation loop, the high-temperature circulation loop includes a first solenoid valve connected to a compressor, the first solenoid valve is connected to a first capillary tube, the first capillary tube is connected to a heat exchange loop, the low-temperature circulation loop includes a second capillary tube, the second capillary tube is connected in parallel with a second solenoid valve, one end of the second capillary tube is connected to a condenser, and the other end of the second capillary tube is connected to the heat exchange loop, the first solenoid valve and the second solenoid valve are connected to a control board, and the control board controls the heat exchange amount by controlling the opening and closing of the first solenoid valve and the second solenoid valve.

2. A high-precision laser chiller according to claim 1, characterized in that: When the first solenoid valve and the second solenoid valve are closed, the heat exchange rate of the heat exchange circuit is 100%; when the first solenoid valve is closed, the second solenoid valve is opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 75-100%; when the first solenoid valve and the second solenoid valve are both opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 50-75%; when the first solenoid valve is opened, the second solenoid valve is opened and closed at a preset frequency, the heat exchange rate of the heat exchange circuit is 25-50%; when the first solenoid valve and the second solenoid valve are both opened, the heat exchange rate of the heat exchange circuit is 0-25%.

3. A high-precision laser chiller according to claim 1, characterized in that: The heat exchange loop includes a water tank and an evaporator, the water tank outlet is connected to the evaporator water inlet, the water tank inlet is connected to a customer device, and the customer device is connected to the evaporator water outlet.

4. A high-precision laser chiller according to claim 3, characterized in that: A heating component is arranged in the water tank, and the heating component is connected to a control panel. The control panel controls the start-up of the heating component according to the water temperature in the water tank and adjusts the temperature control accuracy.

5. A high-precision laser chiller according to claim 3 or 4, characterized in that: A water pump is arranged between the outlet of the water tank and the water inlet of the evaporator, and a spiral water outlet pipe is arranged between the water outlet of the water tank and the water inlet of the water pump.

6. A high-precision laser chiller according to claim 1, 2, 3 or 4, characterized in that: A drying filter is arranged between the gas outlet of the condenser and the second capillary tube.

7. A high-precision laser chiller according to claim 1, 2, 3 or 4, characterized in that: A fan is installed on the condenser.

8. A high-precision laser chiller temperature control method, used for the high-precision laser chiller according to any one of claims 1 to 7, characterized in that: include: The water temperature at the evaporator outlet is obtained. If the water temperature is less than a first temperature threshold, the first solenoid valve is closed, and the second solenoid valve is opened and closed at a preset frequency. The water temperature at the evaporator outlet is obtained. If the water temperature is still lower than the first temperature threshold, the first solenoid valve and the second solenoid valve are both opened and closed at a preset frequency. The water temperature at the evaporator outlet is obtained. If the water temperature is less than a second temperature threshold, the first solenoid valve is opened, and the second solenoid valve is opened and closed at a preset frequency. The water temperature at the water outlet of the evaporator is obtained. If the water temperature is still lower than the second temperature threshold, both the first solenoid valve and the second solenoid valve are opened.

9. A high-precision laser chiller temperature control method according to claim 8, characterized in that: include: If the evaporator heat exchange rate is less than or equal to 50% and the water temperature is lower than the first temperature threshold, the water in the water tank is heated; if the evaporator water outlet temperature is lower than the second threshold, the first solenoid valve is opened and the second solenoid valve is opened and closed at a preset frequency; if the water temperature is greater than the first threshold and the evaporator heat exchange rate is equal to 100%, the water in the water tank is cooled.

10. A high-precision laser chiller temperature control method according to claim 8 or 9, characterized in that: The first temperature threshold is the sum of the required temperature of the evaporator water outlet and the temperature control accuracy; the second temperature threshold is the sum of the required temperature of the evaporator water outlet and the maximum value of the water heating temperature in the water tank.

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