JP6948135B2 - Vehicle air conditioning system, defrost processing method and program for vehicle air conditioning system - Google Patents

Description

The present invention relates to a vehicle air conditioning system, a defrost processing method and a program for a vehicle air conditioning system.

Conventionally, hybrid vehicles such as PHEV vehicles are known to use a heat pump type air conditioning system for vehicles. In such a vehicle air-conditioning system, heating operation is performed with the engine stopped.
Therefore, when the outside air temperature is low, frost may occur on the outdoor heat exchanger. Since frost formation reduces the heat exchange efficiency of the outdoor heat exchanger, a technique for removing frost formation is known.

For example, in Patent Document 1, when the outside air temperature is below freezing point, for example, a part of the coolant that has been heated by cooling the vehicle driving equipment is circulated to the radiator to dissipate heat to the outside air, and the outside air heated by the heat. Is sprayed on the outside evaporator on the downstream side of the radiator to defrost it.
Further, in Patent Document 2, when frost is formed on the outdoor heat exchanger, for example, a control process for forcibly setting the cooling mode is performed, and heat is dissipated from the high-temperature refrigerant by the outdoor heat exchanger, which is generated in the outdoor heat exchanger. Defrosting the frost.

Further, in Patent Document 3 below, the refrigerant circulating in the outdoor heat exchanger is introduced into the indoor unit for generating warm air in the vehicle interior, heated, and dissipated by the outdoor heat exchanger to defrost.

Japanese Unexamined Patent Publication No. 2012-162149 Japanese Unexamined Patent Publication No. 2011-031704 Japanese Unexamined Patent Publication No. 2016-07817

However, in the conventional heat pump type vehicle air conditioning system, during defrosting, the engine is operated and the engine cooling water is circulated to supply heat to the indoor unit and heat the refrigerant circulated in the outdoor heat exchanger. Was there. Therefore, heating was not available at the start of defrosting.
That is, when the engine was started during defrosting, the temperature of the engine cooling water was initially low, and it took time for the temperature to rise. Therefore, until the temperature of the engine cooling water rises at the start of defrosting, the indoor unit for generating warm air in the passenger compartment is not supplied with a sufficient amount of heat from the engine, and the frosted outdoor heat exchanger is used. The refrigerant was circulated and warm air could not be generated.

The present invention has been made in view of the above problems, and an object of the present invention is a heat pump type vehicle air-conditioning system capable of generating warm air in an indoor unit immediately after the start of defrosting, a defrosting treatment method for a vehicle air-conditioning system, and the like. The purpose is to provide a control program for a vehicle air conditioning system.

According to the vehicle air conditioning system of the first aspect of the present invention, a refrigerant system having an outdoor heat exchanger and a water / refrigerant heat exchanger to circulate the refrigerant, and the inside of the water / refrigerant heat exchanger and the indoor unit. A hot water system that has a heater and circulates hot water, a refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing part for a refrigerant and can circulate the refrigerant to an evaporator in the indoor unit, and a hot water system. An engine cooling water system connected by providing an opening / closing part for hot water is provided, and the opening / closing part for the refrigerant is in a closed state, heat is absorbed by the outdoor heat exchanger, and heat is exchanged by the water / refrigerant heat exchanger. A normal operation mode in which heat is radiated by the heater and a defrost operation mode in which the heat absorbed by the evaporator is radiated by the outdoor heat exchanger with the refrigerant opening / closing part and the hot water opening / closing part open. In a vehicle air conditioning system including a mode switching unit that selectively switches, the mode switching unit includes a hot water flow path switching unit that opens the hot water opening / closing unit based on the temperature of the engine cooling water, and the hot water. It has a refrigerant flow path switching portion that opens the refrigerant opening / closing portion after the operation of the refrigerant opening / closing portion.

According to the vehicle air-conditioning system of the present invention, it has a hot water flow path switching portion that opens an opening / closing portion for hot water based on the temperature of engine cooling water. Therefore, the opening / closing part for hot water can be opened after the temperature of the engine cooling water rises, and the heated engine cooling water can be circulated in the hot water system to supply heat to the heater of the indoor unit.
And since it has a refrigerant flow path switching part that opens the refrigerant opening / closing part after the operation of the hot water opening / closing part, even if the refrigerant opening / closing valve is opened immediately after the start of defrosting, the indoor unit is already from the engine cooling water. Heat is supplied and warm air can be generated. Even if a low-temperature refrigerant is supplied from the frosted outdoor heat exchanger to the evaporator in the indoor unit, it is possible to reliably prevent the air discharged from the indoor unit into the vehicle interior from becoming excessively low.
Moreover, since the refrigerant in the refrigerant indoor system can be heated by the heat from the engine cooling water in the indoor unit and supplied to the outdoor heat exchanger, defrosting can be efficiently performed even immediately after the start of defrosting.
Therefore, it is possible to provide a heat pump type vehicle air conditioning system capable of generating warm air by the indoor unit immediately after the start of defrosting.

According to the vehicle air-conditioning system of the second aspect of the present invention, in the first aspect, the hot water flow path switching unit opens the hot water opening / closing unit when the temperature of the engine cooling water is equal to or higher than a predetermined value. It is better to configure it like this.
According to such a configuration, the opening / closing portion for hot water can be easily opened depending on the temperature of the engine cooling water, and the configuration of the vehicle air conditioning system can be simplified.

According to the vehicle air-conditioning system of the third aspect of the present invention, in the second aspect, the hot water opening / closing part may be a thermo valve.
According to such a configuration, the hot water opening / closing unit can be automatically opened / closed without control, and the configuration of the vehicle air conditioning system can be further simplified.

According to the vehicle air-conditioning system of the fourth aspect of the present invention, in the second aspect, the hot water opening / closing part is an electric valve, and the hot water flow path switching part includes the temperature of the engine cooling water in advance. The electric valve may be opened when the set flow path switching condition is satisfied.

According to such a configuration, the hot water opening / closing part can be opened according to the preset flow path switching conditions, so that the hot water opening / closing part can be operated more appropriately.

According to the vehicle air-conditioning system according to the fifth aspect of the present invention, in the first to fourth aspects, the refrigerant opening / closing portion may be opened when the temperature of the indoor unit is equal to or higher than a predetermined value. ..

According to such a configuration, warm air can be more reliably generated in the indoor unit when the defrost treatment is started.

According to the sixth aspect of the present invention, the defrost treatment method includes an outdoor heat exchanger and a refrigerant system having a water / refrigerant heat exchanger to circulate the refrigerant, and the inside of the water / refrigerant heat exchanger and the indoor unit. A hot water system that has a heater and circulates hot water, and a refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing part for a refrigerant and can circulate the refrigerant to an evaporator in the indoor unit, and the hot water system. A defrost treatment method for a vehicle air-conditioning system including an engine cooling water system connected by providing an opening / closing part for hot water, wherein the opening / closing part for a refrigerant is in a closed state and heat is absorbed by the outdoor heat exchanger. In the normal operation mode in which the heat exchanged by the water / refrigerant heat exchanger is dissipated by the heater, and the heat absorbed by the evaporator while the refrigerant opening / closing section and the hot water opening / closing section are open, the heat absorbed by the evaporator is used outdoors. It has a mode switching step to switch between the defrost operation mode in which heat is dissipated by the heat exchanger. The mode switching step further includes a step of determining a preset defrost entry condition, a step of raising the temperature of the engine cooling water when the defrost entry condition is satisfied, and a step of raising the temperature of the engine cooling water to a predetermined temperature or higher. After reaching, the step of connecting the engine cooling water system to the hot water system is included.

According to such a configuration, a step of determining the defrost entry condition, a step of turning on the engine to raise the temperature of the engine cooling water when the defrost entry condition is satisfied, and a step of raising the temperature of the engine cooling water to a predetermined temperature or higher. After that, the engine cooling water system is connected to the hot water system.
Therefore, when the engine cooling water system is connected to the hot water system, the temperature of the cooling water of the engine cooling water system is surely raised, and it is possible to prevent the temperature of the hot water system from dropping due to the connection.
Therefore, it is possible to provide a defrost treatment method capable of generating warm air in the indoor unit immediately after the start of defrost.

According to the defrost treatment method of the seventh aspect of the present invention, in the sixth aspect, it is preferable to detect the temperature of the indoor unit and start the defrost treatment after the temperature reaches a predetermined temperature or higher. ..
According to such a configuration, warm air can be more reliably generated in the indoor unit when the defrost treatment is started.

According to an eighth aspect of the present invention, the program includes a refrigerant system having an outdoor heat exchanger and a water / refrigerant heat exchanger to circulate the refrigerant, and a heater in the water / refrigerant heat exchanger and the indoor unit. A hot water system that circulates hot water, a refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing part for a refrigerant and can circulate the refrigerant to an evaporator in the indoor unit, and a hot water system for hot water. The computer of the vehicle air conditioning system provided with the engine cooling water system connected by providing the opening / closing part is absorbed by the outdoor heat exchanger with the refrigerant opening / closing part closed to exchange the water / refrigerant heat. In the normal operation mode in which the heat exchanged by the device is dissipated by the heater, and the heat absorbed by the evaporator is dissipated by the outdoor heat exchanger while the refrigerant opening / closing section and the hot water opening / closing section are open. It functions as a mode switching unit that switches between the defrost operation mode. The mode switching unit further includes a step of determining a preset defrost entry condition, a step of raising the temperature of the engine cooling water when the defrost entry condition is satisfied, and a step of raising the temperature of the engine cooling water to a predetermined temperature or higher. After reaching, the step of connecting the engine cooling water system to the hot water system is performed.

According to such a configuration, a step of determining the defrost input condition, a step of turning on the engine to raise the temperature of the engine cooling water when the defrost input condition is satisfied, and a step of raising the temperature of the engine cooling water to a predetermined temperature or higher. After that, it has a step of connecting the engine cooling water system to the hot water system.
Therefore, when the engine cooling water system is connected to the hot water system, the temperature of the cooling water of the engine cooling water system is surely raised, and it is possible to prevent the temperature of the hot water system from dropping due to the connection.
Therefore, it is possible to provide a control program for an air conditioning system for a vehicle that can generate warm air in the indoor unit immediately after the start of defrosting.

According to the above invention, it is possible to provide a heat pump type vehicle air-conditioning system, a defrost processing method, and a control program for a vehicle air-conditioning system that can generate warm air in the indoor unit immediately after the start of defrosting.

It is a circuit diagram which shows the air-conditioning system for a vehicle which concerns on 1st Embodiment. It is a block diagram which shows the control system of the air-conditioning system for a vehicle which concerns on 1st Embodiment. It is a flow chart which shows the defrost processing of the air-conditioning system for a vehicle which concerns on 1st Embodiment. It is a circuit diagram which shows the normal operation mode in the vehicle air-conditioning system which concerns on 1st Embodiment. It is a circuit diagram which shows the defrost operation mode in the vehicle air-conditioning system which concerns on 1st Embodiment.

<First Embodiment>
Hereinafter, the first embodiment will be described with reference to the accompanying drawings. The same or corresponding members are designated by the same reference numerals in all drawings, and common description will be omitted.
The vehicle air-conditioning system 1 of the present embodiment is a system that can be mounted on a hybrid vehicle such as a PHEV vehicle and capable of heating operation.

(Overall structure)
As shown in FIGS. 1 and 2, the vehicle air-conditioning system 1 includes a refrigerant system P1, a hot water system P2, an engine cooling water system P3, and a refrigerant chamber system P4, which are in a normal operation mode and a defrost operation mode. It is provided with a mode switching unit 2a that can be switched to and.
The normal operation mode is a mode in which a heating operation can be performed by a heat pump method, and the defrost operation mode is a mode in which an operation for removing frost on the outdoor heat exchanger 13 is possible.

(Refrigerant system)
The refrigerant system P1 includes a compressor 10, a water / refrigerant heat exchanger 11, a three-way solenoid valve V3, a receiver 12, an expansion valve E1, a check valve V5, an outdoor heat exchanger 13, and a two-way solenoid. It has a valve V1 and a refrigerant pipe connecting them, and constitutes a refrigerant flow path 21 through which the refrigerant circulates.
A temperature sensor T1 for detecting the refrigerant temperature is provided between the compressor 10 and the water / refrigerant heat exchanger 11.

The water / refrigerant heat exchanger 11 is provided so that heat can be exchanged between the refrigerant flow path 21 and the hot water flow path 22 of the hot water system P2.
The three-way solenoid valve V3 is connected between the water / refrigerant heat exchanger 11, the receiver 12, and the outdoor heat exchanger 13. In the normal operation mode, the three-way solenoid valve V3 communicates between the water / refrigerant heat exchanger 11 and the receiver 12, and closes the outdoor heat exchanger 13 side. In the defrost operation mode, the water / refrigerant heat exchanger 11 and the outdoor heat exchanger 13 communicate with each other and the receiver 12 side is blocked.

In the receiver 12, the refrigerant pipe 21a from the three-way solenoid valve V3 and the refrigerant pipe 21b from the outdoor heat exchanger 13 are connected to an inlet with a check valve. A refrigerant pipe 21c on the branch portion 21d side is connected to the outlet.
An expansion valve E1 and a check valve V5 are provided on one side of the branch portion 21d, and the outdoor heat exchanger 13 is connected via the branch portion 21e.

The outdoor heat exchanger 13 is configured to be heat exchangeable with a refrigerant through which outside air permeates and flows inside. In the present embodiment, the outdoor heat exchanger 13 functions as an evaporator in the normal operation mode, and flows in the opposite direction to the normal operation mode in the defrost operation mode to function as a condenser.
Further, the discharge path of the outdoor heat exchanger 13 is a refrigerant pipe 21i provided with a two-way solenoid valve V1 in the normal operation mode, and is a refrigerant pipe 21f communicating with the receiver 12 in the defrost operation mode.

The two-way solenoid valve V1 is connected to the compressor 10 by a refrigerant pipe 21g via a branch portion 21h.
A temperature sensor T2 for detecting the refrigerant temperature is provided in the refrigerant pipe 21g between the two-way solenoid valve V1 and the branch portion 21h downstream of the outdoor heat exchanger 13.

(Hot water system)
The hot water system P2 includes a water / refrigerant heat exchanger 11 for exchanging heat with the refrigerant of the refrigerant system P1, a heater 15 in the indoor unit U, a water pump 17, and a four-way valve V4 (opening / closing for hot water). Part) and is connected by a hot water pipe to form a hot water flow path 22 through which hot water circulates.
The hot water does not necessarily have to be water, and may be any liquid that can be used as a heat medium in this system. For example, engine cooling water such as coolant may be used.

The heater 15 in the indoor unit U is provided in the indoor unit U in order to generate warm air introduced into the vehicle interior, and is arranged so as to be heat exchangeable with the gas flowing inside.
The water pump 17 only needs to be able to pump hot water so as to circulate in the hot water system P2.
The four-way valve V4 is interposed between the four-way valve V4 and the engine cooling water system P3, and has two communication flow paths. The four-way valve consists of an electric valve, and is configured to be rotatable by a drive unit (not shown). The four-way valve V4 can be rotated by the hot water flow path switching unit 2d of the control unit 2 to switch the form of the hot water flow path 22 communicated by the two communication flow paths.

Specifically, one communication flow path communicates the hot water pipe 22a on the water pump 17 side with the hot water pipe 22b on the water / refrigerant heat exchanger 11, and the other communication pipe communicates with the cooling water of the engine cooling water system P3. Communicate pipes with each other. Further, by rotating the four-way valve V4, one communication flow path communicates with the hot water pipe 22a on the water pump 17 side and one end of the cooling water pipe 23a of the engine cooling water system P3, and the other communication flow path becomes The hot water pipe 22b on the water / refrigerant heat exchanger 11 side and the other end of the cooling water pipe 23b of the engine cooling water system P3 are communicated with each other.

(Refrigerant chamber system)
The refrigerant chamber system P4 is provided between the branch portion 21d and the branch portion 21h of the refrigerant pipe, and is connected to the refrigerant system P1 by providing an opening / closing portion for the refrigerant.
The refrigerant opening / closing portion provided in the refrigerant system P1 and the refrigerant chamber system P4 of the present embodiment includes an expansion valve E1 and a two-way solenoid valve V2. In the normal operation mode, the refrigerant opening / closing portion is in a state in which the expansion valve E1 is opened and the two-way solenoid valve V2 is closed. In this state, no refrigerant is introduced into the refrigerant chamber system P4.
On the other hand, in the defrost operation mode, the expansion valve E1 is closed and the two-way solenoid valve V2 is opened. In this state, the refrigerant is not introduced between the branch portion 21d and the branch portion 21e, and the refrigerant is introduced into the refrigerant chamber system P4 and flows.

The refrigerant chamber system P4 has a two-way solenoid valve V2, an expansion valve E2, and an evaporator 14, and is a flow path continuous from the refrigerant flow path 21 by a refrigerant pipe from the branch portion 21d to the branch portion 21h. It is provided as.
The evaporator 14 is provided in the indoor unit U, and the refrigerant can evaporate to absorb the heat in the indoor unit U.

(Engine cooling water system)
The engine cooling water system P3 is a flow path for circulating cooling water to the engine 18 and the radiator 19, and has a structure in which the cooling water always flows when the engine is operating.
As described above, the engine cooling water system P3 is provided with a four-way valve V4 and is connected to the hot water system P2 so as to be openable and closable.

(Mode switching unit)
The mode switching unit 2a of the present embodiment is configured so that the refrigerant system P1, the hot water system P2, the engine cooling water system P3, and the refrigerant chamber system P4 can be selectively switched between the normal operation mode and the defrost operation mode. There is.

The mode switching unit 2a includes a defrost input condition determination unit 2b that determines whether or not it is necessary to switch from the normal operation mode to the defrost operation mode, and a timing for switching from the normal operation mode to a flow path such as the refrigerant flow path 21 and the hot water flow path 22. The flow path switching condition determination unit 2c for determination is preset.
Further, the mode switching unit 2a includes a hot water flow path switching unit 2d that opens the four-way valve V4 of the hot water opening / closing part based on the temperature of the engine cooling water, and an expansion valve that constitutes the refrigerant opening / closing part after the four-way valve V4 is operated. It has a refrigerant flow path switching unit 2e that opens and closes by operating E1 and a two-way solenoid valve V2.

In this mode switching unit 2a, the refrigerant opening / closing unit is closed, that is, the expansion valve E1 is opened, the two-way electromagnetic valve V2 is closed, the two-way electromagnetic valve V1 is further opened, and the three-way electromagnetic valve V3 is watered. / By communicating between the refrigerant heat exchanger 11 and the receiver 12 and closing the outdoor heat exchanger 13 side, heat was absorbed by the outdoor heat exchanger 13 and heat was exchanged by the water / refrigerant heat exchanger 11. A normal operation mode in which heat is dissipated by the heater 15 can be configured.
On the other hand, the opening / closing part for the refrigerant is in the open state, that is, the expansion valve E1 is closed and the two-way electromagnetic valve V2 is opened, the two-way electromagnetic valve V1 is closed, and the three-way electromagnetic valve V3 is water / refrigerant. By communicating between the heat exchanger 11 and the outdoor heat exchanger 13 and closing the receiver 12 side, a defrost operation mode in which the heat absorbed by the evaporator 14 is dissipated by the outdoor heat exchanger 13 can be configured.

Next, in such a vehicle air-conditioning system 1, a method of switching from the normal operation mode to the defrost operation mode and performing the defrost processing will be described. This defrosting process can be performed using the control program of the vehicle air conditioning system of the present embodiment.
In the defrost processing method, as shown in FIG. 3, as step S1, as shown in FIG. 4, the vehicle air conditioning system 1 is operated in the normal operation mode.

In the normal operation mode, the four-way valve V4 is disconnected from the engine cooling water system P3 and the hot water system P2 without communicating with each other by the hot water flow path switching unit 2d of the mode switching unit 2a.
In the refrigerant flow path switching unit 2e, the three-way solenoid valve V3 communicates between the water / refrigerant heat exchanger 11 and the receiver 12, the outdoor heat exchanger 13 side is closed, the expansion valve E1 is open, and the two-way solenoid valve is open. The two-way solenoid valve V2 is closed while V1 is open.
In this normal operation mode, the heat absorbed by the outdoor heat exchanger 13 and the heat exchanged by the water / refrigerant heat exchanger 11 is dissipated by the heater 15 to generate warm air in the indoor unit and enter the vehicle interior. It has been introduced.

If heating is continued in the normal operation mode in a state where the outside air temperature is low, the temperature of the surface of the outdoor heat exchanger 13 may be excessively lowered in combination with heat absorption.
The temperature sensors T2, T3, and the like detect the temperature of the refrigerant after heat exchange and the outside air temperature in the outdoor heat exchanger 13, and transmit the temperature to the defrost entry condition determination unit 2b. The defrost input condition determination unit 2b stores in advance a standard for determining the necessity of defrost processing, and determines each temperature transmitted from the temperature sensors T2 and T3 in step S2 based on the standard.
When it is determined that the defrost treatment is necessary, the switch of the engine 18 is turned on in step S3, and the engine cooling water of the engine 18 and the radiator 19 is circulated to raise the temperature.

In step S4, the temperature of the engine cooling water is continuously detected by the temperature sensor T4 and transmitted to the flow path switching condition determination unit 2c of the mode switching unit 2a. In the flow path switching condition determination unit 2c, conditions for communicating the engine cooling water system P3 to the hot water system P2 by the hot water flow path switching unit 2d are set in advance, and the engine cooling to the refrigerant system P1 by the refrigerant flow path switching unit 2e. Conditions for communicating the water system P3 are set.
In the flow path switching condition determination unit 2c, the temperature of the engine cooling water is higher than the temperature detected by the temperature sensor T1, and here the temperature of the engine cooling water detected by the temperature sensor T4 is equal to or higher than the preset temperature threshold T40. When it is determined that the item has reached, the process proceeds to step S5.
The cooling water temperature threshold T40 is a temperature that does not lower the temperature of the refrigerant when the water / refrigerant heat exchanger 11 exchanges heat with the flowing refrigerant as hot water, and raises the temperature inside the indoor unit U. It is set as a possible temperature.

In step S5, the four-way valve V4 is rotationally driven by the hot water flow path switching portion 2d to open the hot water opening / closing portion including the four-way valve V4. As a result, as shown in FIG. 5, the flow path is switched so that the engine cooling water system P3 communicates with the hot water system P2, and the heated engine cooling water circulates in the hot water system P2 and the engine cooling water system P3. Therefore, the inside of the indoor unit U is heated by the heater 15.
In step S6, the temperature sensor T5 continuously detects the temperature inside the indoor unit U and transmits it to the flow path switching condition determination unit 2c of the mode switching unit 2a. The flow path switching condition determination unit 2c proceeds to step S7 when the inside of the indoor unit U reaches the preset temperature threshold value T50 or higher.
This threshold value T50 is set as a temperature that does not excessively lower the temperature of the warm air generated in the indoor unit U when the refrigerant is circulated through the evaporator 14 in the indoor unit U by the refrigerant indoor system P4.

In step S7, the flow path is switched by closing the two-way solenoid valve V1 by the refrigerant flow path switching unit 2e, opening the two-way solenoid valve V2, communicating the three-way solenoid valve V3 with the defrost side, and closing the expansion valve E1. Be done.
As a result, as shown in FIG. 5, the mode is switched to the defrost operation mode, and the refrigerant system P1 flows to the refrigerant chamber system P4 to start the defrost process.

In this way, when the expansion valve E1 of the refrigerant opening / closing part, the two-way solenoid valves V1, V2, the three-way solenoid valve V3, and the four-way valve V4 of the hot water opening / closing part are switched to switch to the defrost operation mode, the refrigerant becomes the evaporator of the indoor unit U. By absorbing heat at 14 and dissipating this heat in the outdoor heat exchanger 13, the outdoor heat exchanger 13 can be defrosted.
After that, when the frost formation is removed, the defrost operation mode can be switched to the normal operation mode again, and the heating operation can be continued.

(Action, effect)
According to the vehicle air-conditioning system 1 of the present embodiment as described above, the hot water flow path switching unit 2d that opens the four-way valve V4 based on the temperature of the engine cooling water is provided. Therefore, the four-way valve V4 can be opened after the engine cooling water temperature rises, and the heated engine cooling water can be circulated to the hot water system P2 to supply heat to the heater 15 of the indoor unit U.

Then, at the same time as or after the operation of the four-way valve V4, the expansion valves E1, the two-way solenoid valves V1, V2, and the three-way solenoid valve V3 of the refrigerant system P1 are operated by the refrigerant flow path switching unit 2e. The heat from the engine cooling water has already been supplied to U. Therefore, even if a low-temperature refrigerant is supplied from the frosted outdoor heat exchanger 13 to the evaporator 14 in the indoor unit U, the temperature of the warm air discharged from the indoor unit U into the vehicle interior is surely lowered excessively. Can be prevented.

Moreover, since the heat from the engine cooling water in the indoor unit U can supply a sufficient amount of heat to the refrigerant of the refrigerant indoor system P4 and supply it to the outdoor heat exchanger 13, defrosting can be performed efficiently even immediately after the start of defrosting. Can be carried out.
Therefore, it is possible to provide a heat pump type vehicle air conditioning system 1 capable of generating warm air by the indoor unit U immediately after the start of defrosting.

In the vehicle air-conditioning system 1 of the present embodiment, the hot water flow path switching unit 2d is configured to open the four-way valve V4 of the hot water opening / closing unit when the temperature of the engine cooling water is equal to or higher than a predetermined value. Therefore, the four-way valve V4 can be easily opened and closed with a simple configuration according to the temperature of the engine cooling water.
Further, when the four-way valve V4 is an electric valve and the flow path switching condition determination unit 2c satisfies the flow path switching conditions set in advance including the temperature of the engine cooling water, the four-way valve is operated by the hot water flow path switching unit 2d. I try to open V4. Therefore, the four-way valve V4 can be operated more appropriately by appropriately adjusting the flow path switching conditions.
Further, when the temperature of the indoor unit U is equal to or higher than a predetermined value, the expansion valve E1 and the two-way solenoid valve V2 of the refrigerant opening / closing part are opened by the refrigerant flow path switching unit 2e, so that when the defrost process is started. In addition, it is possible to prevent the indoor unit U from generating excessively low temperature warm air.

<Modification example>
Although the first embodiment has been described in detail above, the specific embodiment is not limited to the above, and various design changes and the like can be added within a range that does not deviate from the gist. ..
For example, in the above embodiment, the four-way valve V4 of the hot water opening / closing part is controlled and driven by the hot water flow path switching part 2d to switch the hot water flow path 22, but the communication position and the communication position and the hot water opening / closing part are changed according to the temperature. It is also possible to use a thermo valve that can switch the closed position.

Even if the vehicle air-conditioning system 1 shown in FIGS. It is possible to generate warm air with U.
In particular, since the hot water opening / closing unit can be automatically opened / closed without control, the configuration of the vehicle air conditioning system 1 can be simplified.

Further, as in the above embodiment, by combining the thermo valve with the control unit 2, the expansion valve E1 and the two-way solenoid valve V2 of the refrigerant opening / closing unit can be operated according to the set reference. As a result, the control unit 2 can operate the expansion valve E1 and the two-way solenoid valve V2 of the opening / closing part for the refrigerant which are appropriate according to the temperature of the engine cooling water.

Further, in each of the above-described embodiments, the processes of the various processes described above are stored in a computer-readable recording medium in the form of a program, and the various processes are performed by the computer reading and executing this program. It is said. The computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Further, this computer program may be distributed to a computer via a communication line, and the computer receiving the distribution may execute the program.

The above program may be for realizing a part of the above-mentioned functions. Further, it may be a so-called difference file (difference program) that can realize the above-mentioned function in combination with a program already recorded in the computer system. Further, the vehicle air-conditioning system 1 may be composed of one computer or a plurality of computers connected so as to be able to communicate with each other.

Although some embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

1 Vehicle air conditioning system 2 Control unit 2a Mode switching unit 2b Defrost input condition determination unit 2c Flow path switching condition determination unit 2d Hot water flow path switching unit 2e Refrigerant flow path switching unit 10 Compressor 11 Water / refrigerant heat exchanger 12 Receiver 13 Outdoor heat exchanger 14 Evaporator 15 Heater 16 Eamix damper 17 Water pump 18 Engine 19 Radiator 21 Refrigerant flow path 21a, 21b, 21c, 21f, 21g, 21i Refrigerant piping 21d, 21e, 21h Branch 22 Hot water flow path 22a, 22b Hot water piping 23a, 23b Cooling water piping U Indoor unit V1, V2 Two-way electromagnetic valve V3 Three-way electromagnetic valve V4 Four-way valve V5 Check valve E1, E2 Expansion valve T1, T2, T3, T4, T5 Temperature sensor P1 Refrigerant system P2 Hot water System P3 Engine cooling water system P4 Refrigerant chamber system

Claims (7)

A refrigerant system that has an outdoor heat exchanger and a water / refrigerant heat exchanger to circulate the refrigerant,
A hot water system that has a water / refrigerant heat exchanger and a heater in the indoor unit to circulate hot water, and
A refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing portion for the refrigerant and can circulate the refrigerant to the evaporator in the indoor unit.
An engine cooling water system connected to the hot water system by providing an opening / closing part for hot water,
In a normal operation mode in which the refrigerant opening / closing portion is closed, the heat absorbed by the outdoor heat exchanger and the heat exchanged by the water / refrigerant heat exchanger is dissipated by the heater, and the refrigerant opening / closing portion and the above. A mode switching unit that switches between a defrost operation mode in which the heat absorbed by the evaporator is dissipated by the outdoor heat exchanger when the hot water opening / closing unit is open.
In a vehicle air conditioning system equipped with
The mode switching unit includes a hot water flow path switching unit that opens the hot water opening / closing part based on the temperature of the engine cooling water system, and a refrigerant flow path switching unit that opens the refrigerant opening / closing part after the hot water opening / closing part is operated. and parts, the possess,
The hot water flow path switching section opens the hot water opening / closing section when the temperature of the engine cooling water is equal to or higher than a predetermined value.
Air conditioning system for vehicles. The hot water opening / closing part is a thermo valve.
The vehicle air conditioning system according to claim 1. The hot water opening / closing part is an electric valve.
The hot water flow path switching unit opens the electric valve when a preset flow path switching condition including the temperature of the engine cooling water is satisfied.
The vehicle air conditioning system according to claim 1. The vehicle air-conditioning system according to any one of claims 1 to 3 , wherein the refrigerant flow path switching unit opens the refrigerant opening / closing unit when the temperature of the indoor unit is equal to or higher than a predetermined value. A refrigerant system that has an outdoor heat exchanger and a water / refrigerant heat exchanger to circulate the refrigerant,
A hot water system that has a water / refrigerant heat exchanger and a heater in the indoor unit to circulate hot water, and
A refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing portion for the refrigerant and can circulate the refrigerant to the evaporator in the indoor unit.
An engine cooling water system connected to the hot water system by providing an opening / closing part for hot water,
It is a defrosting method for vehicle air-conditioning systems equipped with
In a normal operation mode in which the refrigerant opening / closing portion is closed, the heat absorbed by the outdoor heat exchanger and the heat exchanged by the water / refrigerant heat exchanger is dissipated by the heater, and the refrigerant opening / closing portion and the above. It has a mode switching step to switch between a defrost operation mode in which the heat absorbed by the evaporator is dissipated by the outdoor heat exchanger when the hot water opening / closing part is open.
The mode switching step further
Steps to determine the preset defrost entry conditions and
When the defrosting condition is satisfied, the step of raising the temperature of the engine cooling water and
After the engine cooling water reaches a predetermined temperature or higher, the step of connecting the engine cooling water system to the hot water system and
Defrosting methods for vehicle air conditioning systems, including. The temperature of the indoor unit is detected, and after the temperature reaches a predetermined temperature or higher, the defrost treatment is started.
The defrost treatment method for a vehicle air conditioning system according to claim 5. A refrigerant system that has an outdoor heat exchanger and a water / refrigerant heat exchanger to circulate the refrigerant,
A hot water system that has a water / refrigerant heat exchanger and a heater in the indoor unit to circulate hot water, and
A refrigerant indoor system that is connected to the refrigerant system by providing an opening / closing portion for the refrigerant and can circulate the refrigerant to the evaporator in the indoor unit.
An engine cooling water system connected to the hot water system by providing an opening / closing part for hot water,
Computer for vehicle air conditioning system, equipped with
In a normal operation mode in which the refrigerant opening / closing portion is closed, the heat absorbed by the outdoor heat exchanger and the heat exchanged by the water / refrigerant heat exchanger is dissipated by the heater, and the refrigerant opening / closing portion and the above. With the hot water opening / closing part open, it functions as a mode switching part to switch between the defrost operation mode in which the heat absorbed by the evaporator is dissipated by the outdoor heat exchanger.
The mode switching unit further
Steps to determine the preset defrost entry conditions and
When the defrosting condition is satisfied, the step of raising the temperature of the engine cooling water and
After the engine cooling water reaches a predetermined temperature or higher, the step of connecting the engine cooling water system to the hot water system and
A program that runs.

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