A dual evaporator rooftop air conditioning system for a passenger vehicle

Abstract

The utility model provides a kind of condenser double evaporator's motor coach top-mounted air conditioning system, it is related to air conditioning system technical field, including the compressor fixed in the motor coach bottom, the middle part position of motor coach roof is fixedly installed condenser unit, the front part position of motor coach roof is fixedly installed front evaporator unit, the rear part position of motor coach roof is fixedly installed rear evaporator unit;The exhaust port of the compressor is connected with the inlet of the condenser unit, the outlet of the condenser unit is communicated with the shunt inlet, two outlets of shunt are connected two independent liquid pipelines respectively, one liquid pipeline is sequentially connected front evaporator unit by front thermal expansion valve, another liquid pipeline is sequentially connected rear evaporator unit by rear thermal expansion valve, the outlet of the front evaporator unit is converged with the outlet of the rear evaporator unit by return gas pipeline, and is jointly connected to the suction port of the compressor.

Description

Technical Field

[0001] This utility model relates to the field of air conditioning system technology, specifically to a bus roof-mounted air conditioning system with a dual evaporator condenser. Background Technology

[0002] Large buses of 14 meters or more typically use a single roof-mounted air conditioning system to meet the overall cooling needs of the vehicle. This system usually concentrates the evaporator unit in the center of the roof, distributing cool air to the front, middle, and rear areas of the passenger compartment through a centralized air duct. Because the evaporator is concentrated in the middle, the air delivery path from its air outlet to the front and rear of the carriage is the longest. When air flows in the long air duct, significant pressure loss and flow rate reduction occur due to the friction resistance along the duct. This results in the actual air velocity and air volume at the front and rear air outlets of the carriage being much lower than at the middle air outlet, causing a temperature difference between the front or rear of the carriage and other areas. Existing air conditioning systems generally use a single evaporator unit with a single temperature sensor and expansion valve for control. The system can only adjust the cooling output of the entire system based on the temperature of a single detection point (usually the return air vent temperature or the temperature of a representative area), which exacerbates the temperature unevenness between areas.

[0003] To address the aforementioned issues, the industry has previously adopted the following solution: installing two completely independent air conditioning systems at the front and rear of the roof. While these two independent compressor systems can cover the temperatures on both sides, they have significant drawbacks. In the limited space and electrical load of a bus, operating two independent compressor systems simultaneously increases fuel or electricity consumption. Existing technologies either result in large temperature differences between the front and rear of the passenger compartment due to the centralized arrangement of a single evaporator, or require a dual independent system to address the temperature difference, leading to low energy efficiency and high costs. Utility Model Content

[0004] The purpose of this invention is to provide a bus rooftop air conditioning system with a dual condenser and evaporator, which can solve the technical problem of low energy efficiency in existing bus air conditioning systems.

[0005] To achieve the above objectives, this utility model proposes a bus roof-mounted air conditioning system with a dual evaporator and condenser, including a compressor fixed to the bottom of the bus, a condenser unit fixedly installed in the middle of the bus roof, a front evaporator unit fixedly installed in the front of the bus roof, and a rear evaporator unit fixedly installed in the rear of the bus roof. The compressor's exhaust port is connected to the condenser unit's inlet, and the condenser unit's outlet is connected to the distributor's inlet. The distributor's two outlets are connected to two independent liquid lines. One liquid line passes through the front thermal expansion valve and connects to the front evaporator unit, while the other liquid line passes through the rear thermal expansion valve and connects to the rear evaporator unit. The outlets of the front and rear evaporators unit merge through a return gas line and are connected together to the compressor's suction port.

[0006] Further configured, the distributor adopts a three-way valve, the distributor includes a first outlet and a second outlet, the first outlet of the distributor is connected to the inlet of the front thermostatic expansion valve, and the outlet of the front thermostatic expansion valve is connected to the inlet of the front evaporator unit. The distributor adopts a three-way valve, which has a simple structure and can reliably distribute the refrigerant to the front evaporator unit and the rear evaporator unit, ensuring uniform refrigerant distribution.

[0007] The system is further configured such that the second outlet of the distributor is connected to the inlet of the rear thermal expansion valve, and the outlet of the rear thermal expansion valve is connected to the inlet of the rear evaporator unit. The refrigerant is directed to the rear thermal expansion valve and the rear evaporator unit through the second outlet of the distributor, ensuring that the cooling demand of the rear compartment is met and achieving independent temperature control of the front and rear compartments.

[0008] Further configuration includes a controller installed in the carriage, a front temperature sensor installed in the front carriage, and a rear temperature sensor installed in the rear carriage, which can monitor the temperature of the front and rear carriages in real time and provide data support for independent temperature control.

[0009] Further configured, the controller is electrically connected to the compressor, condenser fan, front / rear thermal expansion valves and front / rear temperature sensors via a CAN bus, enabling efficient communication between the various components of the system and coordinating the operation of the entire air conditioning system.

[0010] A further configuration is provided in which a rear evaporator fan is fixedly installed on one side of the rear evaporator unit and a front evaporator fan is fixedly installed on one side of the front evaporator unit. The front evaporator fan and the rear evaporator fan respectively enhance the heat exchange efficiency of the front evaporator unit 5 and the rear evaporator unit, and accelerate the delivery of cold air.

[0011] Further configured, the front evaporator unit and the rear evaporator unit have identical structures and are interchangeable, simplifying the production and maintenance process.

[0012] A further configuration is made in which the exhaust port of the compressor is connected to the inlet of the condenser unit via a high-pressure pipeline, and the high-pressure pipeline connects the compressor and the condenser unit to ensure the safe delivery of high-temperature and high-pressure refrigerant.

[0013] A further configuration is that the condenser unit is fixedly installed in the middle position of the bus roof by a bracket, and the condenser unit integrates a condensing fan inside. The condenser unit is stably installed in the middle position by the bracket to improve heat dissipation efficiency.

[0014] A further configuration is that the front evaporator unit and the rear evaporator unit are respectively fixedly installed at the front and rear positions of the bus roof by brackets, so that the cold air distribution is more uniform.

[0015] Beneficial effects of one or more of the above technical solutions This invention installs the condenser unit in the middle of the bus roof, and the front and rear evaporator units are installed at the front and rear of the roof, respectively. Compared to a single roof-mounted air conditioner with an excessively concentrated evaporator, the front and rear evaporator units are installed at the front and rear, respectively, shortening the cold air delivery path. This results in a more balanced airflow and consistent temperature in the front, middle, and rear areas of the passenger compartment. At the same time, the single compressor system operates stably, ensuring a balanced airflow and consistent temperature in the front, middle, and rear areas of the passenger compartment. This avoids energy competition between two systems. Furthermore, the front and rear evaporator units, through independent sensors and thermal expansion valves, in conjunction with a controller, can achieve completely independent temperature control for the front and rear compartments. Under the premise of using a single compressor system, the system always operates within the optimal energy efficiency range. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute a limitation thereof.

[0017] Figure 1 This is a schematic diagram of the system of this utility model.

[0018] Figure 2 This is a schematic diagram of the installation structure of this utility model on the roof of a bus.

[0019] In the diagram, 1 is the compressor; 2 is the condenser unit; 21 is the condenser fan; 3 is the distributor; 31 is the distributor inlet; 32 is the distributor first outlet; and 33 is the distributor second outlet. 4. Front thermal expansion valve; 5. Front evaporator unit; 51. Front evaporator fan; 6. Rear thermal expansion valve; 7. Rear evaporator unit; 71. Rear evaporator fan; 8. Controller; 9. Front temperature sensor; 10. Rear temperature sensor; 101. Bus roof; 11. High-pressure pipeline; 12. Return gas pipeline. Detailed Implementation

[0020] The specific implementation of this embodiment will now be described with reference to the accompanying drawings.

[0021] A roof-mounted air conditioning system for buses with a dual condenser and evaporator, as described in the reference. Figures 1 to 2 The system includes a compressor 1 fixed to the bottom of the bus, a condenser unit 2 fixedly installed in the middle of the bus roof 101, a front evaporator unit 5 fixedly installed at the front of the bus roof 101, and a rear evaporator unit 7 fixedly installed at the rear of the bus roof 101. The exhaust port of the compressor 1 is connected to the inlet of the condenser unit 2, and the outlet of the condenser unit 2 is connected to the inlet 31 of the distributor. The two outlets of the distributor 3 are respectively connected to two independent liquid pipelines. One liquid pipeline passes through the front thermal expansion valve 4 and connects to the front evaporator unit 5, and the other liquid pipeline passes through the rear thermal expansion valve 6 and connects to the rear evaporator unit 7. The outlets of the front evaporator unit 5 and the rear evaporator unit 7 are merged through the return gas pipeline 12 and connected together to the suction port of the compressor 1. By installing the condenser unit 2 in the middle of the bus roof 101, and the front evaporator unit 5 and the rear evaporator unit 7 in the front and rear respectively, the cold air delivery path is shortened, so that the air speed in the front, middle and rear areas of the carriage is balanced and the temperature is consistent. At the same time, the single compressor 1 system operates stably, avoiding energy competition between the two systems and improving energy efficiency.

[0022] The distributor 3 employs a three-way valve and includes a first outlet 32 ​​and a second outlet 33. The first outlet 32 ​​is connected to the inlet of the front thermal expansion valve 4 via a liquid pipeline, and the outlet of the front thermal expansion valve 4 is connected to the inlet of the front evaporator unit 5. The distributor 3, with its simple structure, reliably distributes refrigerant to the front evaporator unit 5 and the rear evaporator unit 7, ensuring uniform refrigerant distribution and thus consistent cooling performance between the front and rear compartments.

[0023] The second outlet 33 of the distributor is connected to the inlet of the rear thermal expansion valve 6 via a liquid pipeline, and the outlet of the rear thermal expansion valve 6 is connected to the inlet of the rear evaporator unit 7. The refrigerant is directed to the rear thermal expansion valve 6 and the rear evaporator unit 7 through the second outlet 33 of the distributor, ensuring that the cooling needs of the rear compartment are met and achieving independent temperature control between the front and rear compartments.

[0024] It also includes a controller 8 installed in the passenger compartment, a front temperature sensor 9 installed in the front passenger compartment, and a rear temperature sensor 10 installed in the rear passenger compartment. Through the cooperation of the controller 8, the front temperature sensor 9, and the rear temperature sensor 10, the temperature of the front and rear passenger compartments can be monitored in real time, providing data support for independent temperature control, thereby accurately adjusting the cooling output and improving passenger comfort.

[0025] Controller 8 is electrically connected to compressor 1, condenser fan 21, front thermal expansion valve 4, rear thermal expansion valve 6, front temperature sensor 9, and rear temperature sensor 10 via a CAN bus. This CAN bus connection enables efficient communication between the system components, ensuring that controller 8 can quickly respond to temperature changes, coordinate the operation of the entire air conditioning system, and improve control accuracy and system stability. Figure 2 When the system is started, the driver or passengers can set the target temperature for the front and rear compartments through the control panel. The controller 8 receives real-time temperature signals from the front temperature sensor 9 and the rear temperature sensor 10. If the temperature of both the front and rear compartments is higher than the set value, the controller 8 will stop the compressor 1 from running. At the same time, the front evaporator fan 51 will work to deliver strong cold air into the compartment. The speed of the compressor 1 and the speed of the condenser fan 21 are determined by the combined cooling demand of the front and rear compartments to ensure the efficient and stable operation of the system.

[0026] A rear evaporator fan 71 is fixedly installed on one side of the rear evaporator unit 7, and a front evaporator fan 51 is fixedly installed on one side of the front evaporator unit 5. The front evaporator fan 51 and the rear evaporator fan 71 respectively enhance the heat exchange efficiency of the front evaporator unit 5 and the rear evaporator unit 7, accelerate the delivery of cold air, ensure uniform airflow speed in the front and rear of the vehicle compartment, further reduce the temperature difference, and improve the cooling effect.

[0027] The front evaporator unit 5 and the rear evaporator unit 7 have identical structures and are interchangeable. This interchangeability simplifies production and maintenance processes, reduces spare parts inventory costs, and improves the system's versatility and reliability.

[0028] The exhaust port of the compressor 1 is connected to the inlet of the condenser unit 2 via a high-pressure pipeline 11. Connecting the compressor 1 and the condenser unit 2 via the high-pressure pipeline 11 ensures the safe delivery of high-temperature, high-pressure refrigerant, improving system reliability and safety.

[0029] The condenser unit 2 is fixedly installed in the middle of the bus roof 101 by a bracket. The condenser unit 2 integrates a condensing fan 21. The condenser unit 2 is securely installed in the middle by a bracket, and the integrated condensing fan 21 improves heat dissipation efficiency and ensures condensation effect. At the same time, the structure is compact and saves installation space.

[0030] The front evaporator unit 5 and the rear evaporator unit 7 are fixedly installed at the front and rear of the bus roof 101 respectively via brackets. The front evaporator unit 5 and the rear evaporator unit 7 are fixed at the front and rear positions respectively via brackets, which is a firm installation, reasonable layout, shortens the air duct length, reduces pressure loss, makes the cold air distribution more uniform, and improves the temperature consistency of the carriage.

[0031] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A roof-mounted air conditioning system for a bus with dual evaporators, characterized in that, It includes a compressor fixed to the bottom of the bus, a condenser unit fixedly installed in the middle of the bus roof, a front evaporator unit fixedly installed at the front of the bus roof, and a rear evaporator unit fixedly installed at the rear of the bus roof. The compressor's exhaust port is connected to the condenser unit's inlet, and the condenser unit's outlet is connected to the distributor's inlet. The distributor's two outlets are connected to two independent liquid lines. One liquid line passes through the front thermal expansion valve and connects to the front evaporator unit, while the other liquid line passes through the rear thermal expansion valve and connects to the rear evaporator unit. The outlets of the front and rear evaporators unit merge through a return gas line and are connected together to the compressor's suction port.

2. The dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The distributor employs a three-way valve and includes a first outlet and a second outlet. The first outlet is connected to the inlet of the front thermal expansion valve, and the outlet of the front thermal expansion valve is connected to the inlet of the front evaporator unit.

3. The dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The second outlet of the distributor is connected to the inlet of the rear thermal expansion valve, and the outlet of the rear thermal expansion valve is connected to the inlet of the rear evaporator unit.

4. The dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, It also includes a controller installed in the carriage, a front temperature sensor installed in the front carriage, and a rear temperature sensor installed in the rear carriage.

5. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The controller is electrically connected to the compressor, condenser fan, front / rear thermostatic expansion valves, and front / rear temperature sensors via a CAN bus.

6. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, A rear evaporator fan is fixedly installed on one side of the rear evaporator unit, and a front evaporator fan is fixedly installed on one side of the front evaporator unit.

7. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The front evaporator unit and the rear evaporator unit have the same structure and can be used interchangeably.

8. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The compressor's exhaust port is connected to the inlet of the condenser unit via a high-pressure pipeline.

9. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The condenser unit is fixedly installed in the middle of the bus roof by a bracket, and the condenser unit integrates a condenser fan.

10. A dual-evaporator roof-mounted air conditioning system for buses according to claim 1, characterized in that, The front evaporator unit and the rear evaporator unit are fixedly installed on the front and rear of the bus roof by brackets, respectively.

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