Vehicle air conditioner and transport refrigeration unit dual system

Abstract

The present invention provides a dual system for vehicle air conditioners and transport refrigerating machines, which includes an air conditioner compressor, a refrigerating machine compressor, an outdoor heat exchanger, an air conditioner indoor heat exchanger, two throttling devices, a gas-liquid separator, a refrigerating machine evaporator and a subcooler; and respectively form an air conditioning circuit and a refrigeration circuit. In the air conditioning circuit: the output side of the first tube pass of the outdoor heat exchanger is connected to a first branch, the output side of the first throttling device is connected to a second branch, a first stop valve is installed on the first branch, a second stop valve is installed on the second branch, the output sides of the first stop valve and the second stop valve converge and then are connected to a third throttling device, the third throttling device is connected to the inlet of the condensation pipeline of the subcooler, and the outlet of the condensation pipeline of the subcooler is connected to the loop interface of the air conditioner compressor. Without increasing additional costs, this system provides a large amount of subcooling for the refrigeration circuit through the subcooling cycle of the air conditioning circuit, and can also prevent the outdoor heat exchanger of the vehicle air conditioner from frosting in winter.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle refrigeration and air conditioning, and specifically, to a dual system of vehicle air conditioner and transport refrigerating machine. Background Art

[0002] At present, for refrigerated vehicles, especially electric refrigerated vehicles, energy consumption is an important reference factor affecting the overall use of the vehicle.

[0003] In addition to the refrigerating machine system for refrigeration, a refrigerated vehicle also has an additional independent air conditioning system. The two operate independently of each other, consuming double energy and resulting in waste of cooling capacity.

[0004] Moreover, the refrigerating machine system accounts for a relatively high proportion of the overall energy consumption of the refrigerated vehicle.

[0005] At the same time, most current transport refrigerating machine systems use a split single-cycle refrigerant to supercool the main circuit system to improve the refrigerating capacity and energy efficiency of the refrigerating machine system. However, the degree of supercooling improved by such systems is limited.

[0006] For example, in the invention patent with the application number: 201620071100.8 and the invention name: Dual refrigeration unit for refrigerated transport vehicle, a single compressor is used to provide cooling capacity for both the air conditioner and the refrigerating machine, which also achieves the purpose of energy saving. However, this method places too high a requirement on the capacity of the compressor, resulting in high performance requirements for the compressor and no reduction in cost.

[0007] Another example is the invention patent application with the application number: 201810208821.2 and the invention name: Refrigeration and air conditioning combined system using cascaded cold energy of liquefied natural gas. The cold energy released during the gasification process of hydraulic natural gas is used to provide a cold source for the air conditioning system, reduce the pressure ratio of the air conditioning compressor, improve the operating efficiency of the air conditioner, and reduce energy consumption. However, this method requires an external cold source such as liquefied natural gas. In a vehicle-mounted system, there is no external cold source to supplement the cold quantity supply.

[0008] In order to solve the above problems, people have been seeking an ideal technical solution. Summary of the Invention

[0009] The object of the present invention is to address the deficiencies of the prior art, thereby providing a dual system of vehicle air conditioner and transport refrigerating machine that, without increasing additional costs, uses a mechanical subcooling cycle to provide a large degree of subcooling for the transport refrigerating machine, increase the refrigerating capacity and energy efficiency of the transport refrigerating machine system; and in winter conditions, the outdoor heat exchanger of the electric vehicle air conditioner can recover the heat released by the outdoor heat exchanger of the transport refrigerating machine to prevent frosting of the outdoor heat exchanger of the vehicle air conditioner.

[0010] To achieve the above object, the technical solution adopted by the present invention is: a dual system of a vehicle air conditioner and a transport refrigerating machine, including an air conditioner compressor, a refrigerating machine compressor, an outdoor heat exchanger, an air conditioner indoor heat exchanger, two throttling devices, a gas-liquid separator, a refrigerating machine evaporator and a subcooler;

[0011] The air conditioner compressor, the first tube pass of the outdoor heat exchanger, the first throttling device, and the air conditioner indoor heat exchanger are sequentially connected end to end to form an air conditioner circuit;

[0012] The refrigerating machine compressor, the second tube pass of the outdoor heat exchanger, the heat exchange pipeline of the subcooler, the second throttling device, the refrigerating machine evaporator and the gas-liquid separator are sequentially connected end to end to form a refrigeration circuit;

[0013] In the air conditioner circuit:

[0014] The output side of the first tube pass of the outdoor heat exchanger is connected to a first branch, the output side of the first throttling device is connected to a second branch, a first stop valve is installed on the first branch, a second stop valve is installed on the second branch, the output sides of the first stop valve and the second stop valve converge and then are connected to a third throttling device, the third throttling device is connected to the inlet of the condensation pipeline of the subcooler, and the outlet of the condensation pipeline of the subcooler is connected to the circuit interface of the air conditioner compressor.

[0015] Based on the above, the outdoor heat exchanger is an integrated heat exchanger, the integrated heat exchanger includes the first tube pass, the second tube pass and heat exchange fins, the first tube pass and the second tube pass are independent of each other, and the heat exchange fins are distributed outside the first tube pass and the second tube pass for supporting the pipeline and enhancing heat dissipation.

[0016] Based on the above, a cooling fan is arranged outside the heat exchange fins of the outdoor heat exchanger.

[0017] Based on the above, the outlet of the air conditioner compressor is connected to a four-way reversing valve, the first interface of the four-way reversing valve communicates with the outlet of the air conditioner compressor, the second interface communicates with the first tube pass of the outdoor heat exchanger, the third interface communicates with the circuit interface of the air conditioner compressor, and the fourth interface communicates with the air conditioner indoor heat exchanger.

[0018] Based on the above, the first stop valve and the second stop valve are linked with the start switch of the refrigerating machine compressor. When the refrigerating machine compressor starts, one of the first stop valve and the second stop valve is opened.

[0019] Based on the above, when the air conditioner circuit operates in the refrigeration state and the refrigerating machine compressor starts, the first stop valve is opened and the second stop valve is closed.

[0020] Based on the above, when the air conditioner circuit operates in the heating state and the refrigerating machine compressor starts, the second stop valve is opened and the first stop valve is closed.

[0021] As described above, when the chiller compressor is closed during the refrigeration operation of the air-conditioning circuit, both the first shut-off valve and the second shut-off valve are closed.

[0022] As described above, the subcooler is a plate heat exchanger.

[0023] The present invention has prominent substantive features and remarkable progress compared with the prior art. Specifically, the present invention has the following advantages:

[0024] 1. During the refrigeration process of the air-conditioning system, it operates in conjunction with the transport chiller, and provides subcooling for the refrigeration circuit through the subcooler, improving the refrigeration capacity and energy efficiency ratio of the transport chiller.

[0025] 2. During the heating process of the air-conditioning system, the heat released by the chiller refrigeration system is recovered through the outdoor heat exchanger, avoiding frosting of the outdoor heat exchanger.

[0026] 3. The entire system only adds a set of subcoolers and several shut-off valves, with low transformation cost and excellent effect.

[0027] 4. The system adopts linkage start control, and the entire combined operation process runs automatically without additional control processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic structural diagram of the dual-system of the vehicle air conditioner and the transport chiller in the present invention.

[0029] In the figure: 1. Air-conditioning compressor; 2. Chiller compressor; 3. Outdoor heat exchanger; 4. Air-conditioning indoor heat exchanger; 5. Gas-liquid separator; 6. Chiller evaporator; 7. Subcooler; 8. First throttling device; 9. Four-way reversing valve; 10. Second throttling device; 11. First shut-off valve; 12. Second shut-off valve; 13. Third throttling device. DETAILED DESCRIPTION OF THE INVENTION

[0030] The technical solutions of the present invention will be further described in detail below through specific embodiments.

[0031] As Figure 1 shown, a dual-system of a vehicle air conditioner and a transport chiller includes an air-conditioning compressor 1, a chiller compressor 2, an outdoor heat exchanger 3, an air-conditioning indoor heat exchanger 4, two throttling devices, a gas-liquid separator 5, a chiller evaporator 6, and a subcooler 7;

[0032] The air-conditioning compressor 1, the first tube pass of the outdoor heat exchanger 3, the first throttling device 8, and the air-conditioning indoor heat exchanger 4 are connected end to end in sequence to form an air-conditioning circuit.

[0033] Among them, the outlet side of the air-conditioning compressor 1 is connected to the four-way reversing valve 9. The first interface of the four-way reversing valve 9 is communicated with the outlet of the air-conditioning compressor 1, the second interface is communicated with the first tube pass of the outdoor heat exchanger 3, the third interface is communicated with the return interface of the air-conditioning compressor 1, and the fourth interface is communicated with the air-conditioning indoor heat exchanger 4. By switching the four-way reversing valve 9, the switching between refrigeration and heating is realized.

[0034] The cold machine compressor 2, the second tube pass of the outdoor heat exchanger 3, the heat exchange pipeline of the subcooler 7, the second throttling device 10, the cold machine evaporator 6 and the gas-liquid separator 5 are connected end to end in sequence to form a refrigeration cycle. The subcooler adopts a plate heat exchanger.

[0035] The outdoor heat exchanger 3 is designed as an integrated heat exchanger. The integrated heat exchanger includes the first tube pass, the second tube pass and heat exchange fins. The first tube pass and the second tube pass are independent of each other. The heat exchange fins are distributed outside the first tube pass and the second tube pass for supporting the pipeline and enhancing heat dissipation; a cooling fan is arranged outside the heat exchange fins of the outdoor heat exchanger.

[0036] In the air-conditioning loop:

[0037] The output side of the first tube pass of the outdoor heat exchanger 3 is connected to the first branch, and the output side of the first throttling device 8 is connected to the second branch. The first branch is equipped with a first stop valve 11, and the second branch is equipped with a second stop valve 12. The output sides of the first stop valve 11 and the second stop valve 12 converge and then are connected to a third throttling device 13. The third throttling device 13 is connected to the inlet of the condensation pipeline of the subcooler 7, and the outlet of the condensation pipeline of the subcooler 7 is connected to the return interface of the air-conditioning compressor 1.

[0038] The first stop valve and the second stop valve are linked with the start switch of the cold machine compressor.

[0039] When the cold machine compressor starts during the refrigeration operation of the air-conditioning loop, the first stop valve opens and the second stop valve closes.

[0040] When the cold machine compressor starts during the heating operation of the air-conditioning loop, the second stop valve opens and the first stop valve closes.

[0041] When the cold machine compressor is closed during the refrigeration operation of the air-conditioning loop, both the first stop valve and the second stop valve close.

[0042] Its working process is as follows

[0043] Working process 1, in summer conditions, start the vehicle air-conditioning system alone:

[0044] The refrigerant gas at high temperature and high pressure is discharged through the air-conditioning compressor 1, enters the outdoor heat exchanger 3 and condenses into a refrigerant liquid at medium temperature and high pressure. The refrigerant liquid at medium temperature and high pressure becomes a two-phase gas-liquid fluid at low temperature and low pressure through the first throttling device 8, and then absorbs heat and evaporates into a refrigerant gas at low temperature and low pressure through the air-conditioning indoor heat exchanger 4 in the cab, and finally returns to the air-conditioning compressor 1.

[0045] Working process 2, start the transport refrigeration system alone:

[0046] The refrigerant gas at high temperature and high pressure is discharged through the refrigeration compressor 2, enters the outdoor heat exchanger 3 and condenses and releases heat into a refrigerant liquid at medium temperature and high pressure. The refrigerant liquid at medium temperature and high pressure becomes a two-phase gas-liquid fluid at low temperature and low pressure through the second throttling device 10, and then absorbs heat and evaporates into a refrigerant gas at low temperature and low pressure through the refrigeration evaporator 6 arranged inside the refrigerated box body, and finally returns to the refrigeration compressor 2.

[0047] Working process 3, in summer condition, the vehicle air-conditioning system and the transport refrigeration system operate jointly:

[0048] The refrigerant gas at high temperature and high pressure is discharged through the air-conditioning compressor, enters the outdoor heat exchanger 3 and condenses into a refrigerant liquid at medium temperature and high pressure. The refrigerant liquid at medium temperature and high pressure is divided into two paths. One path throttles through the first throttling device 8 and then enters the air-conditioning indoor heat exchanger 4 to absorb heat and evaporate into a refrigerant gas at low temperature and low pressure, and returns to the air-conditioning compressor 1; the other path passes through the first stop valve 11 and throttles through the third throttling device 13 into a two-phase gas-liquid fluid at low temperature and low pressure, and then evaporates and absorbs heat through the sub-cooler 7 (absorbing the heat of the refrigerant liquid at the outlet of the outdoor heat exchanger 3 which acts as a condenser in the transport refrigeration system), and returns to the air-conditioning compressor 1.

[0049] For the transport refrigeration system, the refrigerant gas at high temperature and high pressure is discharged through the refrigeration compressor 2, enters the outdoor heat exchanger 3 and condenses and releases heat into a refrigerant liquid at medium temperature and high pressure. The refrigerant liquid at medium temperature and high pressure is further sub-cooled by releasing heat through the sub-cooler 7, and then becomes a two-phase gas-liquid fluid at low temperature and low pressure through the second throttling device 10, and then absorbs heat and evaporates into a refrigerant gas at low temperature and low pressure through the refrigeration evaporator 6 in the refrigerated box body, and finally returns to the refrigeration compressor 2.

[0050] Working process 4, in winter condition, start the vehicle air-conditioning system alone:

[0051] The refrigerant gas at high temperature and high pressure is discharged through the air-conditioning compressor 1, enters the air-conditioning indoor heat exchanger 4 and condenses into a refrigerant liquid at medium temperature and high pressure. The refrigerant liquid at medium temperature and high pressure becomes a two-phase gas-liquid fluid at low temperature and low pressure through the first throttling device 8, and then absorbs heat and evaporates into a refrigerant gas at low temperature and low pressure through the outdoor heat exchanger 3, and finally returns to the air-conditioning compressor 1.

[0052] Working process 5, winter condition, combined operation of vehicle air-conditioning system and transport refrigeration system:

[0053] The high-temperature and high-pressure refrigerant gas is discharged through the air-conditioning compressor and enters the air-conditioning indoor heat exchanger 5 in the cab to be condensed into a medium-temperature and high-pressure refrigerant liquid. The medium-temperature and high-pressure refrigerant liquid is divided into two paths. One path throttles through the first throttling device 8 and then enters the outdoor heat exchanger 3 to absorb heat and evaporate into a low-temperature and low-pressure refrigerant gas, and then returns to the air-conditioning compressor 1. The other path passes through the second stop valve 12 and throttles through the third throttling device 13 into a low-temperature and low-pressure gas-liquid two-phase fluid, and then evaporates and absorbs heat through the subcooler 7 (absorbing the heat of the refrigerant liquid at the outlet of the outdoor heat exchanger 3, which is the condenser of the transport refrigeration system), and then returns to the air-conditioning compressor 1.

[0054] For the transport refrigeration system, the high-temperature and high-pressure refrigerant gas is discharged through the refrigeration compressor 2 and enters the outdoor heat exchanger 3 to condense and release heat into a medium-temperature and high-pressure refrigerant liquid. The medium-temperature and high-pressure refrigerant liquid is further subcooled by releasing heat through the subcooler 7, and then becomes a low-temperature and low-pressure gas-liquid two-phase fluid through the second throttling device 10, and then absorbs heat and evaporates into a low-temperature and low-pressure refrigerant gas through the refrigeration evaporator 6 in the refrigerated box body, and finally returns to the refrigeration compressor 2.

[0055] The dual-system of vehicle air-conditioning and transport refrigeration proposed in this solution shunts part of the refrigerant of the vehicle air-conditioning to subcool the transport refrigeration system, improves the refrigeration capacity and energy efficiency of the refrigeration system, and achieves the purpose of energy saving. At the same time, in winter, the vehicle air-conditioning operates for heating, and the air-conditioning outdoor heat exchanger can recover the heat of the outdoor heat exchanger of the refrigeration system to prevent frosting.

[0056] Without additional cost, using an additional system to subcool the refrigeration system can greatly increase the subcooling degree of the refrigeration system, and thus improve its refrigeration capacity and energy efficiency.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the specific implementation manners of the present invention or perform equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A dual system for vehicle air conditioners and transport refrigeration units, characterized in that: It includes an air-conditioning compressor, a chiller compressor, an outdoor heat exchanger, an air-conditioning indoor heat exchanger, two throttling devices, a gas-liquid separator, a chiller evaporator and a subcooler; The air-conditioning compressor, the first tube pass of the outdoor heat exchanger, the first throttling device, and the air-conditioning indoor heat exchanger are connected end to end in sequence to form an air-conditioning circuit; The chiller compressor, the second tube pass of the outdoor heat exchanger, the heat exchange pipeline of the subcooler, the second throttling device, the chiller evaporator and the gas-liquid separator are connected end to end in sequence to form a refrigeration circuit; In the air-conditioning circuit: The output side of the first tube pass of the outdoor heat exchanger is connected to a first branch, the output side of the first throttling device is connected to a second branch, a first stop valve is installed on the first branch, a second stop valve is installed on the second branch, the output sides of the first stop valve and the second stop valve converge and then are connected to a third throttling device, the third throttling device is connected to the inlet of the condensation pipeline of the subcooler, and the outlet of the condensation pipeline of the subcooler is connected to the circuit interface of the air-conditioning compressor.

2. The vehicle air conditioner and transport refrigeration unit dual system according to claim 1, characterized in that: The outdoor heat exchanger is an integrated heat exchanger, and the integrated heat exchanger includes the first tube pass, the second tube pass and heat exchange fins. The first tube pass and the second tube pass are independent of each other, and the heat exchange fins are distributed outside the first tube pass and the second tube pass for supporting the pipeline and enhancing heat dissipation.

3. The vehicle air conditioner and transport refrigeration unit dual system according to claim 2, characterized in that: A cooling fan is arranged outside the heat exchange fins of the outdoor heat exchanger.

4. The vehicle air conditioner and transport refrigeration unit dual system according to claim 3, wherein: The outlet of the air-conditioning compressor is connected to a four-way reversing valve. The first interface of the four-way reversing valve communicates with the outlet of the air-conditioning compressor, the second interface communicates with the first tube pass of the outdoor heat exchanger, the third interface communicates with the circuit interface of the air-conditioning compressor, and the fourth interface communicates with the air-conditioning indoor heat exchanger.

5. The vehicle air conditioner and transport refrigeration unit dual system according to claim 4, characterized in that: The first stop valve and the second stop valve are linked with the start switch of the chiller compressor. When the chiller compressor starts, one of the first stop valve and the second stop valve is opened.

6. The vehicle air conditioner and transport refrigeration unit dual system according to claim 5, characterized in that: When the air-conditioning circuit operates in the refrigeration state and the chiller compressor starts, the first stop valve is opened and the second stop valve is closed.

7. The vehicle air conditioner and transport refrigeration unit dual system according to claim 5 or 6, characterized in that: When the air-conditioning circuit operates in the heating state and the chiller compressor starts, the second stop valve is opened and the first stop valve is closed.

8. The vehicle air conditioner and transport refrigeration unit dual system according to claim 7, characterized in that: When the air-conditioning circuit operates in the refrigeration state and the chiller compressor is closed, both the first stop valve and the second stop valve are closed.

9. The vehicle air conditioner and transport refrigeration unit dual system according to claim 8, characterized in that: The subcooler is a plate heat exchanger.

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