Vehicle-mounted air conditioning system and vehicle

Abstract

The application provides a vehicle-mounted air conditioning system and a vehicle, and applies to the technical field of vehicle-mounted air conditioning. The vehicle-mounted air conditioning system comprises a refrigeration circuit and a defrosting branch. A first evaporator is connected with a first output end of a thermal expansion valve in the refrigeration circuit through a first pipeline, connected with a first liquid outlet end of a liquid accumulator in the refrigeration circuit through a second pipeline, and connected with a first end of a gas-liquid separator in the refrigeration circuit through a third pipeline. In the case that the vehicle-mounted air conditioning system is in a defrosting mode, the first pipeline is not conducted, the second pipeline is conducted, the refrigeration circuit continues to refrigerate, and the defrosting branch heats the first evaporator in the refrigeration circuit for defrosting. In the case that the vehicle-mounted air conditioning system is in a refrigeration mode, the first pipeline is conducted, the second pipeline is not conducted, and the refrigeration circuit and the defrosting branch both refrigerate, so that the problem that the existing vehicle-mounted air conditioning system needs to interrupt refrigeration when defrosting, the system structure is complex, or the system occupies a large space can be solved.

Description

Technical Field

[0001] This application relates to the field of vehicle air conditioning technology, and in particular to a vehicle air conditioning system and vehicle. Background Technology

[0002] Currently, vehicle air conditioning systems, as an important device for improving passenger comfort, are widely used in various types of passenger vehicles. As people's requirements for the riding environment continue to increase, air conditioning systems not only need to meet basic cooling needs, but also need to solve various problems that arise during operation, such as evaporator frosting.

[0003] In related technologies, vehicle air conditioning systems mainly employ three solutions: single-cooling air conditioning, hot gas bypass defrosting systems, and independent defrosting evaporators. Single-cooling air conditioning systems require a complete shutdown of cooling operation during defrosting, leading to significant temperature fluctuations inside the passenger compartment and impacting passenger comfort. While hot gas bypass defrosting systems can achieve continuous cooling, they require modifications to high-pressure piping, increasing system complexity and energy consumption. Independent defrosting evaporators address the shortcomings of the first two solutions, but require additional evaporator installation, consuming valuable interior space and increasing manufacturing costs, making them particularly unsuitable for space-constrained compact buses. Utility Model Content

[0004] The purpose of this application is to provide an in-vehicle air conditioning system and vehicle that solves the problems of existing in-vehicle air conditioning systems requiring interruption of cooling during defrosting, complex system structure, or large space occupation.

[0005] In a first aspect, embodiments of this application provide an in-vehicle air conditioning system, which includes a refrigeration circuit and a defrosting branch.

[0006] The defrost branch includes a first pipe, a second pipe, a third pipe, and a first evaporator. The first evaporator is connected to the first output terminal of the thermostatic expansion valve in the refrigeration circuit via the first pipe. The first evaporator is connected to the first liquid outlet terminal of the liquid receiver in the refrigeration circuit via the second pipe. The first evaporator is connected to the first terminal of the gas-liquid separator in the refrigeration circuit via the third pipe. When the vehicle air conditioning system is in defrost mode, the first pipe is not connected, the second pipe is connected, the refrigeration circuit continues to cool, and the defrost branch heats the first evaporator in the refrigeration circuit for defrosting. When the vehicle air conditioning system is in cooling mode, the first pipe is connected, the second pipe is not connected, and both the refrigeration circuit and the defrost branch perform cooling.

[0007] One possible implementation includes a refrigeration circuit comprising a compressor, a condenser, a liquid receiver, a thermostatic expansion valve, a second evaporator, and a gas-liquid separator. A first end of the compressor is connected to the outlet of the gas-liquid separator. A second end of the compressor is connected to the first end of the condenser. A second end of the condenser is connected to the inlet of the liquid receiver. A first outlet of the liquid receiver is connected to the first end of a solenoid valve. A second outlet of the liquid receiver is connected to the input of the thermostatic expansion valve. A first output of the thermostatic expansion valve is connected to the first end of a check valve. A second output of the thermostatic expansion valve is connected to the first end of the second evaporator. A second end of the second evaporator is connected to the second end of the gas-liquid separator. A third end of the gas-liquid separator is connected to the first end of the compressor.

[0008] In one possible implementation, the first pipeline includes a check valve. A first end of the check valve is connected to a first output end of a thermostatic expansion valve. A second end of the check valve is connected to a first end of a first evaporator. The check valve allows unidirectional flow from the output end of the thermostatic expansion valve to the first evaporator.

[0009] One possible implementation is that the distance between the installation position of the one-way valve and the thermal expansion valve is no more than 20mm. The one-way valve is configured to allow unidirectional flow from the output end of the thermal expansion valve to the first evaporator when the pressure difference between the two ends of the one-way valve exceeds a preset threshold.

[0010] In one possible implementation, the second pipeline includes a solenoid valve. A first end of the solenoid valve is connected to a first outlet end of the liquid reservoir. A second end of the solenoid valve is connected to a second end of the first evaporator.

[0011] In one possible implementation, the system also includes a control unit. The control unit is connected to the solenoid valve. The control unit is configured to control the state of the solenoid valve in response to control commands. These control commands include cooling commands and defrosting commands.

[0012] One possible implementation involves the following: when the vehicle's air conditioning system is in defrost mode, the one-way valve in the first line is deactivated, while the solenoid valve in the second line is activated. The thermostatic expansion valve is configured to supply refrigerant to the second evaporator to allow it to continue cooling. The one-way valve is configured to prevent backflow of high-pressure refrigerant from the solenoid valve to the thermostatic expansion valve. The solenoid valve is configured to directly supply high-pressure refrigerant from the refrigeration circuit to the first evaporator to allow it to heat and defrost.

[0013] In one possible implementation, the thermostatic expansion valve is configured to deliver refrigerant to the second evaporator at a first opening degree. This first opening degree is less than the maximum opening degree of the thermostatic expansion valve.

[0014] One possible implementation involves the one-way valve in the first pipeline being open only when the vehicle's air conditioning system is in cooling mode, while the solenoid valve in the second pipeline is closed. The thermostatic expansion valve is configured to supply refrigerant to both the first and second evaporators, ensuring that both evaporators are cooling.

[0015] The vehicle air conditioning system provided in this embodiment features an independent defrost branch. This branch is activated when the vehicle is in defrost mode. At this time, high-temperature, high-pressure liquid refrigerant from the receiver is directly injected into the first evaporator via a dedicated second pipe, providing the heat required for defrosting. Simultaneously, the system precisely cuts off the connection between the defrost branch and the main refrigeration circuit through the automatic locking function of the one-way valve in the first pipe. This completely blocks the high-pressure refrigerant generated during defrosting from flowing back into the refrigeration circuit and interfering with its operation. Meanwhile, the thermostatic expansion valve continues to supply low-temperature, low-pressure refrigerant to the second evaporator according to cooling demand, allowing it to maintain its original cooling state. The two evaporators operate independently in this mode, fundamentally solving the problem of traditional air conditioning systems requiring interruption of cooling during defrosting, thus improving the stability of the vehicle's interior temperature and the comfort of the occupants.

[0016] Secondly, embodiments of this application provide a vehicle that may include an in-vehicle air conditioning system as described in the first aspect and any possible implementation thereof. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 A system architecture diagram of an in-vehicle air conditioning system provided in this application embodiment; Figure 2 This is a system architecture diagram of a vehicle provided in an embodiment of this application.

[0019] 1-Compressor; 2-Condenser; 3-Receiver; 4-Thermal expansion valve; 5-Second evaporator; 6-Gas-liquid separator; 7-One-way valve; 8-Solenoid valve; 9-First evaporator; 10-First pipeline; 11-Second pipeline; 12-Third pipeline; Vehicle air conditioning system 100; Vehicle 200; Refrigeration circuit 101; Defrosting circuit 102. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] In the operation of air conditioning systems in commercial vehicles such as buses, especially in low-temperature and high-humidity environments, frost formation on the evaporator surface is a common problem. The frost layer obstructs airflow and heat exchange, leading to reduced cooling efficiency and decreased airflow, thus requiring regular defrosting.

[0023] Currently, common defrosting solutions such as reverse cycle defrosting or compressor shutdown defrosting require a complete halt to refrigeration operation, leading to temperature fluctuations inside the vehicle and poor comfort. While hot gas bypass defrosting can achieve defrosting without shutting down the system, it requires complex modifications to the high-pressure piping, resulting in a complex system, low energy efficiency, and reliability risks. Other solutions employ independent defrosting systems, but this further increases the system's size, complexity, and cost.

[0024] Based on this, this application provides an in-vehicle air conditioning system and a vehicle. The in-vehicle system includes a refrigeration circuit and a defrost branch. The defrost branch includes a first pipe, a second pipe, a third pipe, and a first evaporator. The first evaporator is connected to the first output terminal of the thermostatic expansion valve in the refrigeration circuit via the first pipe, the first evaporator is connected to the first liquid outlet terminal of the liquid receiver in the refrigeration circuit via the second pipe, and the first evaporator is connected to the first end of the gas-liquid separator in the refrigeration circuit via the third pipe. When the in-vehicle air conditioning system is in defrost mode, the first pipe is not connected, the second pipe is connected, the refrigeration circuit continues to cool, and the defrost branch heats and defrosts the first evaporator in the refrigeration circuit. When the in-vehicle air conditioning system is in cooling mode, the first pipe is connected, the second pipe is not connected, and both the refrigeration circuit and the defrost branch perform cooling.

[0025] The vehicle air conditioning system provided in this embodiment features an independent defrost branch. This branch is activated when the vehicle is in defrost mode. At this time, high-temperature, high-pressure liquid refrigerant from the receiver is directly injected into the first evaporator via a dedicated second pipe, providing the heat required for defrosting. Simultaneously, the system precisely cuts off the connection between the defrost branch and the main refrigeration circuit through the automatic locking function of the one-way valve in the first pipe. This completely blocks the high-pressure refrigerant generated during defrosting from flowing back into the refrigeration circuit and interfering with its operation. Meanwhile, the thermostatic expansion valve continues to supply low-temperature, low-pressure refrigerant to the second evaporator according to cooling demand, allowing it to maintain its original cooling state. The two evaporators operate independently in this mode, fundamentally solving the problem of traditional air conditioning systems requiring interruption of cooling during defrosting, thus improving the stability of the vehicle's interior temperature and the comfort of the occupants.

[0026] The solutions provided in the embodiments of this application will now be described in conjunction with the specific accompanying drawings.

[0027] On one hand, embodiments of this application provide a vehicle air conditioning system. For example... Figure 2 As shown, the vehicle air conditioning system 100 includes a refrigeration circuit 101 and a defrosting branch 102.

[0028] The refrigeration circuit 101 is the main component of the vehicle air conditioning system 100 that enables cooling. This refrigeration circuit 101 includes a compressor 1, a condenser 2, a liquid receiver 3, a thermostatic expansion valve 4, a second evaporator 5, and a gas-liquid separator 6, which are connected sequentially through pipes to form a closed loop. The liquid receiver 3 has a first liquid outlet and a second liquid outlet. The second evaporator 5 can be a cooling zone evaporator.

[0029] The defrost branch 102 is connected in parallel with the refrigeration circuit to perform the defrosting function on the first evaporator 9. The defrost branch 102 includes a first pipe 10, a second pipe 11, a third pipe 12, and the first evaporator 9. The first evaporator 9 can be a defrost zone evaporator.

[0030] It should be noted that the first evaporator 9 can be a component that is physically independent but functionally coordinated with the second evaporator 5, or it can be integrated with the second evaporator 5 in the same evaporator but with the flow channels isolated from each other.

[0031] Specifically, the first pipeline 10 includes a one-way valve 7. The first end of the one-way valve 7 is connected to the first output end of the thermal expansion valve 4, and the second end of the one-way valve 7 is connected to the first end of the first evaporator 9.

[0032] The one-way valve 7 can be installed within 20 mm of the thermostatic expansion valve 4 to ensure a fast response. At the same time, the one-way valve 7 is designed to allow refrigerant to flow unidirectionally from the thermostatic expansion valve 4 to the first evaporator 9 only, and can reliably block reverse flow when the pressure difference between the two ends exceeds a preset threshold (e.g., 0.3 MPa).

[0033] The second pipeline 11 includes a solenoid valve 8. The first end of the solenoid valve 8 is connected to the first liquid outlet of the liquid reservoir 3, and the second end of the solenoid valve 8 is connected to the second end of the first evaporator 9.

[0034] In this second pipeline, the liquid receiver is directly connected to the first evaporator. Compared with the traditional defrosting branch with a throttling device, this process can provide a high-pressure direct injection channel from the liquid receiver directly to the first evaporator, which can increase the defrosting temperature rise rate of the vehicle air conditioning system 100 in defrosting mode to 8-10℃ / min.

[0035] The third pipe 12 connects the third end of the first evaporator 9 to the first end of the gas-liquid separator 6.

[0036] Furthermore, the vehicle air conditioning system 100 provided in this application embodiment also includes a control unit, which is electrically connected to the solenoid valve 8 and is used to receive control commands (such as operations from the driver or signals from the frost sensor) and control the opening and closing of the solenoid valve 8.

[0037] Furthermore, combining Figure 1 The vehicle air conditioning system 100 shown in the embodiment operates as follows: When the vehicle air conditioning system 100 is in cooling mode, the control unit issues a cooling command, controlling the solenoid valve 8 to be closed. At this time, the second pipeline 11 is not open. The liquid refrigerant from the receiver 3 is throttled by the thermal expansion valve 4 and divided into two paths: one path enters the second evaporator 5 for cooling; the other path enters the first evaporator 9 for cooling through the one-way valve 7 in the first pipeline 10. After absorbing heat and evaporating, the two refrigerants merge through their respective pipelines to the gas-liquid separator 6, and are finally drawn into the compressor 1, completing the refrigeration cycle. In this mode, both evaporators of the entire system participate in cooling, providing maximum cooling capacity.

[0038] When defrosting of the first evaporator 9 is required, the control unit issues a defrost command, causing the solenoid valve 8 to open. At the same time, since the first evaporator 9 no longer draws refrigerant from the main line, the opening of the thermostatic expansion valve 4 can be reduced accordingly, for example, reduced to 30% of the maximum opening of the thermostatic expansion valve 4.

[0039] At this time, the refrigerant at the first end of the one-way valve 7 in the first pipeline 10 is low-temperature and low-pressure refrigerant, while the refrigerant at the second end of the one-way valve 7 becomes high-temperature and high-pressure due to the high-temperature and high-pressure refrigerant being injected into the first evaporator 9 through the second pipeline 11. At this time, the pressure difference of the refrigerant at both ends of the one-way valve 7 is greater than 0.3MPa. Under the action of the pressure difference, the one-way valve 7 closes quickly, effectively blocking the high-pressure backflow.

[0040] Furthermore, at this point, the defrosting branch 102 becomes a high-temperature, high-pressure liquid refrigerant from the receiver 3, which is directly injected into the first evaporator 9 through the solenoid valve 8 in the second pipeline 11. This refrigerant releases sensible and latent heat on the cold fins of the first evaporator 9, rapidly melting the frost layer and achieving defrosting. The defrosted refrigerant returns to the gas-liquid separator 6 through the third pipeline 12.

[0041] The refrigeration circuit then switches to a state where the thermostatic expansion valve 4 continues to supply refrigerant to the second evaporator 5, ensuring continuous cooling of the vehicle interior. Since the first evaporator 9 no longer draws refrigerant from the main circuit, the opening of the thermostatic expansion valve 4 can be reduced accordingly (i.e., the first opening) to match the cooling demand of only the second evaporator 5, achieving energy saving and precise control.

[0042] Once defrosting is complete, the control unit closes the solenoid valve 8, and the vehicle air conditioning system 100 switches back to cooling mode.

[0043] On the other hand, embodiments of this application provide a vehicle. For example... Figure 2 As shown, the vehicle 200 includes Figure 1 The vehicle air conditioning system 100 shown.

[0044] It should be noted that the functions of vehicle 200 are implemented based on the vehicle air conditioning system 100, and the specific implementation process can be referred to the above. Figure 1 The implementation process of the vehicle air conditioning system 100 shown is not described in detail in this application.

[0045] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A vehicle air conditioning system, characterized in that, The vehicle air conditioning system includes a refrigeration circuit and a defrosting branch; The defrosting branch includes a first pipeline, a second pipeline, a third pipeline, and a first evaporator. The first evaporator is connected to the first output end of the thermostatic expansion valve in the refrigeration circuit through the first pipeline. The first evaporator is connected to the first liquid outlet end of the liquid receiver in the refrigeration circuit through the second pipeline. The first evaporator is connected to the first end of the gas-liquid separator in the refrigeration circuit through the third pipeline. When the vehicle air conditioning system is in defrost mode, the first pipe is not connected, the second pipe is connected, the refrigeration circuit continues to refrigerate, and the defrost branch is the first evaporator in the refrigeration circuit that is heated for defrosting. When the vehicle air conditioning system is in cooling mode, the first pipe is open, the second pipe is closed, and both the cooling circuit and the defrosting branch are cooling.

2. The system according to claim 1, characterized in that, The refrigeration circuit includes a compressor, a condenser, a liquid receiver, the thermostatic expansion valve, a second evaporator, and a gas-liquid separator; The first end of the compressor is connected to the outlet end of the gas-liquid separator; the second end of the compressor is connected to the first end of the condenser; the second end of the condenser is connected to the inlet end of the liquid receiver; the first outlet end of the liquid receiver is connected to the second circuit; the second outlet end of the liquid receiver is connected to the input end of the thermostatic expansion valve; the first output end of the thermostatic expansion valve is connected to the first circuit; the second output end of the thermostatic expansion valve is connected to the first end of the second evaporator; the second end of the second evaporator is connected to the second end of the gas-liquid separator; and the third end of the gas-liquid separator is connected to the first end of the compressor.

3. The system according to claim 1, characterized in that, The first pipeline includes a one-way valve; the first end of the one-way valve is connected to the first output end of the thermal expansion valve; the second end of the one-way valve is connected to the first end of the first evaporator; the one-way valve allows unidirectional flow from the output end of the thermal expansion valve to the first evaporator.

4. The system according to claim 3, characterized in that, The installation position of the one-way valve is no more than 20mm away from the thermal expansion valve. The one-way valve is configured to allow unidirectional flow from the output end of the thermal expansion valve to the first evaporator when the pressure difference between the two ends of the one-way valve exceeds a preset threshold.

5. The system according to claim 1, characterized in that, The second pipeline includes a solenoid valve; the first end of the solenoid valve is connected to the first liquid outlet of the liquid reservoir; the second end of the solenoid valve is connected to the second end of the first evaporator.

6. The system according to claim 1, characterized in that, The system also includes a control unit; the control unit is connected to the solenoid valve; the control unit is configured to control the state of the solenoid valve in response to control commands; the control commands include cooling commands and defrosting commands.

7. The system according to claim 1, characterized in that, When the vehicle air conditioning system is in defrost mode, the one-way valve in the first pipeline is not open, while the solenoid valve in the second pipeline is open. The thermostatic expansion valve is configured to deliver refrigerant to the second evaporator so that the second evaporator continues to cool; The one-way valve is configured to block the backflow of high-pressure refrigerant from the solenoid valve to the thermostatic expansion valve; The solenoid valve is configured to directly transfer high-pressure refrigerant from the refrigeration circuit to the first evaporator to heat and defrost the first evaporator.

8. The system according to claim 7, characterized in that, The thermostatic expansion valve is configured to transfer the refrigerant to the second evaporator at a first opening degree; the first opening degree is less than the maximum opening degree of the thermostatic expansion valve.

9. The system according to claim 1, characterized in that, When the vehicle air conditioning system is in cooling mode, the one-way valve in the first pipeline is open in one direction, and the solenoid valve in the second pipeline is not open. The thermostatic expansion valve is configured to deliver refrigerant to the first evaporator and the second evaporator so that both the first evaporator and the second evaporator perform refrigeration.

10. A vehicle, characterized in that, The vehicle includes the vehicle air conditioning system as described in any one of claims 1-9.

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