Fixed-frequency vehicle air conditioning system
By setting up a hot air bypass branch and a multi-stage adjustment device in the fixed-frequency vehicle air conditioning system, the problem of limited cooling capacity adjustment range is solved, and precise temperature control and power consumption optimization are achieved.
Patent Information
- Application Number
- CN202423010963.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2034-12-06
AI Technical Summary
Fixed-frequency vehicle air conditioning systems have a limited range of cooling capacity adjustment when the temperature changes greatly. The conventional 5-level adjustment mode cannot meet the needs, resulting in frequent start-stop, limited temperature control accuracy, and high power consumption.
A hot gas bypass branch is set between the compressor and the evaporator, and the first bypass branch and the second bypass branch are connected in parallel. Combined with an adjustable speed fan, an electronic expansion valve and a solenoid valve, the cooling capacity demand of the refrigeration system is adjusted in multiple stages.
It enables precise adjustment of cooling capacity under different temperature scenarios, improves temperature control accuracy, and reduces frequent start-stop cycles and power consumption.
Smart Images
Figure CN223840699U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of air conditioning technology, and in particular to a fixed-frequency vehicle air conditioning system. Background Technology
[0002] When rail vehicle air conditioning uses fixed-frequency air conditioning units, its cooling capacity adjustment range is limited. When the vehicle environment is variable, the temperature varies greatly, and the cooling capacity demand range is wide, its conventional 5-level adjustment method cannot meet the usage requirements, resulting in problems such as frequent start-stop, limited temperature control accuracy, and high power consumption. Utility Model Content
[0003] The main purpose of this utility model is to solve the above-mentioned problems and deficiencies and provide a fixed-frequency vehicle air conditioning system, which achieves the adjustment of the cooling capacity of the refrigeration system by setting up a hot air bypass branch and opening the hot air bypass branch.
[0004] To achieve the purpose of this utility model, this utility model provides a fixed-frequency vehicle air conditioning system, which adopts the following technical solution:
[0005] A fixed-frequency vehicle air conditioning system includes a compressor, a condenser, and an evaporator connected by pipes, with a hot gas bypass branch provided between the compressor and the evaporator.
[0006] Furthermore, the fixed-frequency vehicle air conditioning system is a fixed-frequency refrigeration vehicle air conditioning system, with the first end of the hot gas bypass branch located at the outlet end of the compressor and the second end located at the inlet end of the evaporator.
[0007] Furthermore, a four-way valve is provided between the compressor and the condenser, and the first end of the hot gas bypass branch is located at the outlet end of the compressor, and the second end is located at the return end of the four-way valve.
[0008] Furthermore, the fixed-frequency vehicle air conditioning system is a fixed-frequency refrigeration vehicle air conditioning system, and the hot air bypass branch includes a first bypass branch and a second bypass branch connected in parallel.
[0009] Furthermore, the first end of both the first bypass branch and the second bypass branch is located at the outlet end of the compressor, and the second end of both is located at the inlet end of the evaporator.
[0010] Furthermore, a solenoid valve for controlling the on / off state of the hot gas bypass branch is provided, and an electronic expansion valve is provided between the evaporator and the condenser.
[0011] Furthermore, the opening degree of the electronic expansion valve is adjustable.
[0012] Furthermore, the opening degree of the electronic expansion valve is between 0 and 500 steps.
[0013] Furthermore, adjustable speed fans are provided at the evaporator and condenser.
[0014] In summary, the fixed-frequency vehicle air conditioning system provided by this utility model has the following technical advantages compared with the prior art:
[0015] By configuring variable speed fans and variable diameter throttling devices, different cooling capacity requirements for different temperature scenarios can be met.
[0016] The flow rate in the main circuit of the refrigeration system is changed by adjusting the opening of the electronic expansion valve.
[0017] The thermal bypass branch includes multiple branches connected in parallel, and the large bypass regulation of the refrigeration system is achieved by opening multiple branches. Attached Figure Description
[0018] Figure 1 This utility model provides a connection diagram for a fixed-frequency vehicle air conditioning system. Figure 1 ;
[0019] Figure 2 This utility model provides a connection diagram for a fixed-frequency vehicle air conditioning system. Figure 2 ;
[0020] Figure 3 This utility model provides a connection diagram for a fixed-frequency vehicle air conditioning system. Figure 3 ;
[0021] Figure 4 This utility model provides a control method for an electronic expansion valve in a fixed-frequency vehicle air conditioning system;
[0022] Figure 5 This utility model provides a method for controlling an electromagnetic valve in a fixed-frequency vehicle air conditioning system.
[0023] Among them, compressor 1, condenser 2, electronic expansion valve 3, evaporator 4, condenser fan 5, evaporator fan 6, hot gas bypass branch 7, solenoid valve 8, first bypass branch 71, second bypass branch 72, first solenoid valve 81, second solenoid valve 82, and four-way valve 9.
[0024] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this utility model, but are not intended to limit the scope of this utility model.
[0026] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0027] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0028] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0029] This utility model provides a fixed-frequency vehicle air conditioning system, including a compressor 1, a condenser 2 and an evaporator 4 connected by pipelines, and a hot gas bypass branch 7 is provided between the compressor 1 and the evaporator 4.
[0030] The fixed-frequency vehicle air conditioning system provided by this utility model has a hot air bypass branch 7 located between the compressor and the evaporator. Its specific location is described in the following embodiments:
[0031] Example 1
[0032] like Figure 1 As shown, the air conditioning system is a fixed-frequency air conditioning system with only cooling function. The compressor 1 is a fixed-frequency compressor 1. A condenser fan 5 is installed at the condenser 2 and an evaporator fan 6 is installed at the evaporator 4. Both the condenser fan 5 and the evaporator fan 6 are adjustable-speed fans, and their speed and frequency are adjusted according to the cooling capacity requirements.
[0033] A hot gas bypass branch 7 is provided between compressor 1 and evaporator 4. The first end of the hot gas bypass branch 7 is the input end, which is located at the outlet end of compressor 1, and the second end is the output end, which is located at the inlet end of evaporator 4. The refrigerant output from compressor 1 is split. Part of the refrigerant flows back to compressor 1 in the normal direction after heat exchange through condenser 2 and evaporator 4, completing one refrigeration cycle. The other part flows through the hot gas bypass branch 7, merges with the refrigerant from condenser 2, enters evaporator 4, and then flows back to compressor 1.
[0034] When the air conditioning system is running, compressor 1 compresses the gaseous refrigerant into a high-temperature, high-pressure gaseous state. A portion of the gaseous refrigerant enters condenser 2, releases heat, and cools down to become a medium-temperature, high-pressure liquid refrigerant. This liquid refrigerant then merges with another portion of the high-temperature, high-pressure refrigerant that is diverted from the hot gas bypass branch 7. This process increases the temperature of the refrigerant entering evaporator 4, allowing it to absorb heat from the air (cooling the air) and vaporize, turning back into a gaseous state. The vapor then returns to compressor 1, completing one cycle.
[0035] By setting up a hot gas bypass branch 7, the temperature of the refrigerant entering the evaporator 4 is increased in cooling mode, thereby adjusting the cooling effect.
[0036] Example 2
[0037] like Figure 2 As shown, the air conditioning system also includes a four-way valve installed at the outlet of compressor 1. The four-way valve changes the refrigerant flow direction, enabling the air conditioning system to achieve heat pump function and realize cooling and heating functions.
[0038] Similarly, as described in Embodiment 1, an adjustable speed fan is installed at the condenser 2 and evaporator 4, and a hot gas bypass branch 7 is installed between the compressor 1 and evaporator 4. The difference is that:
[0039] In this embodiment, the first end (input end) of the hot gas bypass branch 7 is located on the pipeline between the outlet end of the compressor 1 and the inlet end of the four-way valve, and the second end (output end) is located on the pipeline between the return end of the four-way valve and the return end of the compressor 1. The return end of the four-way valve refers to the pipeline end where, in cooling mode, the refrigerant exits from the evaporator 4 and returns to the compressor 1 via the four-way valve, and in heating mode, the refrigerant exits from the condenser 2 and returns to the compressor 1 via the four-way valve.
[0040] Example 3
[0041] In this embodiment, similar to Embodiment 1, the air conditioning system is also a fixed-frequency air conditioner with a single cooling function. The difference is that, in this embodiment, as... Figure 3 As shown, the hot gas bypass branch 7 includes a first bypass branch 71 and a second bypass branch 72 connected in parallel. The first ends of both the first bypass branch 71 and the second bypass branch 72 are located at the outlet end of the compressor 1, and the second ends are located at the inlet end of the evaporator 4. If necessary, multiple bypass branches can be set in parallel to perform multi-stage adjustment of the cooling capacity.
[0042] As described above in the three embodiments of the hot gas bypass branch 7, an adjustable throttling device is installed between the evaporator 4 and the condenser 2, such as an electronic expansion valve with an adjustable opening, which is adjustable between 0 and 500 steps. A solenoid valve 88 is installed on the hot gas bypass branch 7 to control the opening and closing of the branch. In the third embodiment, a first solenoid valve 818 and a second solenoid valve 828 are respectively installed on the first bypass branch 71 and the second bypass branch 72. The unloading function is realized by controlling the opening and closing of the solenoid valve 8 on the hot gas bypass branch 7, and the cooling capacity of the refrigeration system is adjusted in conjunction with the opening of the electronic expansion valve.
[0043] In embodiment three, at least two parallel bypass branches are provided, and each branch is equipped with a solenoid valve 8. Each solenoid valve 8 can be controlled to open or close separately. According to the cooling capacity requirements, the opening and closing of each solenoid valve 8 can be adjusted to achieve multi-level control of the cooling capacity.
[0044] Furthermore, in addition to controlling the on / off state of each solenoid valve 8 and the opening degree of the electronic expansion valve to achieve multi-level regulation of cooling capacity, the cooling efficiency can also be further regulated by coordinating the speed and frequency of the condenser fan 5 and / or the evaporator fan 6.
[0045] In this application, the opening degree of the electronic expansion valve is adjusted according to the suction pressure and suction temperature of the compressor 1, while also taking into account the application environment of the air conditioning system and the difference between the set temperature and the actual temperature. The control method of the electronic expansion valve described below is applicable to both refrigeration and heating systems.
[0046] like Figure 4 As shown, after the air conditioning system is turned on, it detects the outdoor and indoor temperatures. When the temperature difference between the indoor and outdoor temperatures is greater than the preset value M℃, the opening of the electronic expansion valve is adjusted between the P zone and the O zone; otherwise, the opening of the electronic expansion valve is adjusted between the Q zone and the P zone.
[0047] After the electronic expansion valve opens, the suction pressure and suction temperature of compressor 1 are detected. Based on these conditions, the opening of the electronic expansion valve is further adjusted. When the temperature difference between the suction pipe temperature and the suction pipe pressure of compressor 1 is less than a preset value, the opening of the electronic expansion valve is decreased; otherwise, the opening is increased.
[0048] After the opening of the electronic expansion valve is adjusted according to the suction pressure and suction temperature of compressor 1 for a preset time Y seconds, the suction pressure and suction temperature of compressor 1 are checked again and a judgment is made again to adjust the opening of the electronic expansion valve. This cycle continues until the air conditioning system stops.
[0049] like Figure 4 As shown, the symbols in the diagram represent:
[0050] T_suction -- Temperature of the suction pipe of compressor 1;
[0051] T(P suction) -- Temperature corresponding to the suction pipe pressure of compressor 1;
[0052] Tin -- Indoor temperature;
[0053] Tex -- Outdoor temperature;
[0054] N℃ -- Set value, typically ranging from 2 to 5℃
[0055] Y seconds – a set value, typically ranging from 10 seconds to 120 seconds.
[0056] P - Expansion valve opening range, typically 200-300 steps.
[0057] Q - Expansion valve opening range, typically 50 to 80 steps.
[0058] O -- Expansion valve opening, typically ranging from 400 to 480 steps.
[0059] The solenoid valve 8 is adjusted based on the difference between the indoor temperature and the set temperature, while also taking into account the low-pressure area of the system. For example, in the single-cooling air conditioning system with multiple hot gas bypass branches 7 described in Embodiment 3, such as... Figure 5 As shown, the specific adjustment relationship is as follows:
[0060] After the air conditioning system is turned on, if the temperature difference between the indoor temperature and the outdoor temperature is less than the set value X℃ and the first solenoid valve 818 is already open, the system will further detect if the temperature difference between the temperature of the compressor 1 suction pipe and the temperature corresponding to the compressor 1 suction pipe pressure is greater than the preset value. If it is greater than 5℃, the second solenoid valve 828 will be opened. After the set temperature is reached for Y seconds, the system will re-detect if the temperature difference between the temperature of the compressor 1 suction pipe and the temperature corresponding to the compressor 1 suction pipe pressure is small, in order to re-determine whether the second solenoid valve 828 should remain open.
[0061] When the temperature difference between the indoor temperature and the outdoor temperature is greater than the set value X℃, and the first solenoid valve 818 is open, the current state is maintained, and after a set time Y seconds, the temperature difference between the indoor temperature and the outdoor temperature is detected and judged again.
[0062] When the temperature difference between the temperature of the compressor 1 suction pipe and the temperature corresponding to the pressure of the compressor 1 suction pipe is less than or equal to the preset value, such as 5℃, the current state is maintained, and after a set time Y seconds, the temperature difference between the indoor temperature and the outdoor temperature is detected and judged again.
[0063] Figure 5 In the text, each symbol represents:
[0064] T_suction -- Temperature of the suction pipe of compressor 1;
[0065] T(P suction) -- Temperature corresponding to the suction pipe pressure of compressor 1;
[0066] Tin -- Indoor temperature;
[0067] Tset -- Indoor set temperature;
[0068] X℃ -- Set value, typically ranging from 2 to 5℃
[0069] Y seconds – a set value, typically ranging from 10 seconds to 120 seconds.
[0070] The 5℃ shown in the figure is just an example; it can be adjusted according to actual needs in practical applications.
[0071] It should be noted that the opening adjustment of the electronic expansion valve is a conventional technology in the field. The above description is only one possible method. This part is not the focus of this application and will not be elaborated. Existing or future technologies are applicable to this application, and should not be regarded as a limitation on the location of the air conditioning system to be protected by this application, especially the hot gas bypass branch 7, based on the above description.
[0072] In summary, the fixed-frequency vehicle air conditioning system provided by this utility model has the following technical advantages compared with the prior art:
[0073] By configuring variable speed fans and variable diameter throttling devices, different cooling capacity requirements for different temperature scenarios can be met.
[0074] The flow rate in the main circuit of the refrigeration system is changed by adjusting the opening of the electronic expansion valve.
[0075] The thermal bypass branch includes multiple branches connected in parallel, and the large bypass regulation of the refrigeration system is achieved by opening multiple branches.
[0076] As described above, similar technical solutions can be derived from the given solutions. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model, without departing from the scope of this utility model's technical solution, shall still fall within the scope of this utility model's technical solution.
Claims
1. A fixed-frequency vehicle air conditioning system, characterized in that: It includes a compressor, a condenser, and an evaporator connected by pipelines, with a hot gas bypass branch provided between the compressor and the evaporator; The hot gas bypass branch includes at least a first bypass branch and a second bypass branch connected in parallel; The first ends of the first bypass branch and the second bypass branch are both located at the outlet end of the compressor, and the second ends are spaced apart at the inlet end of the evaporator. Each of the aforementioned hot gas bypass branches is equipped with a solenoid valve to control the opening and closing of the branch.
2. A fixed-frequency vehicle air conditioning system as described in claim 1, characterized in that: The fixed-frequency vehicle air conditioning system is a fixed-frequency refrigeration vehicle air conditioning system.
3. A fixed-frequency vehicle air conditioning system as described in claim 1, characterized in that: An electronic expansion valve is installed between the condenser and the evaporator.
4. A fixed-frequency vehicle air conditioning system as described in claim 3, characterized in that: The opening degree of the electronic expansion valve is adjustable.
5. A fixed-frequency vehicle air conditioning system as described in claim 4, characterized in that: The opening degree of the electronic expansion valve is adjustable between 0 and 500 steps.
6. A fixed-frequency vehicle air conditioning system as described in any one of claims 1 to 5, characterized in that: An adjustable-speed fan is installed at the evaporator and condenser.