JPH0232486Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is an air conditioner for a vehicle that has a refrigeration system for cooling the room and a hot water heating system that heats the room using engine water temperature. It is related to the device.

(Prior Art) Vehicle air conditioners have been known that include a cooling refrigeration system for cooling the room and a hot water heating system that heats the room using engine water temperature.

This cooling refrigeration system includes a compressor, a condenser, a liquid tank, an expansion valve, and an evaporator, which are connected in order through a cooling refrigerant pipe. This cooling refrigeration system circulates refrigerant between a condenser and an evaporator, circulates indoor air through the evaporator, causes the refrigerant to absorb heat from the indoor air via the evaporator, and condenses the refrigerant in the condenser. The heat taken by the refrigerant is then released outside to cool the room. In addition, the hot water type heating system guides engine cooling water to a heat exchanger inside the vehicle interior, and exchanges heat between the inside air or outside air and the engine cooling water to raise the temperature of the indoor air, thereby heating the room. I'm starting to do it. The liquid tank is necessary to separate the refrigerant gas contained in the refrigerant that has been liquefied in the condenser to make it a complete liquid refrigerant that does not contain gas, and is generally used as a component of the refrigeration cycle. There are some items that are not provided because they are not necessarily indispensable.

(Problem to be solved by the invention) By the way, there are cases where it is desired to run the vehicle immediately after starting the engine and heat the interior of the vehicle in the middle period of a predetermined range of outside air temperature from 0°C to 15°C. With hot water heating systems, heating effects cannot be expected unless the engine water temperature as a cooling water temperature reaches 40°C or higher, which is a predetermined temperature determined in consideration of the heating efficiency of the hot water heating system. Immediately after the vehicle is started, outside air is shut off and the vehicle is started running while being careless about heating the interior.With conventional systems, heating effects cannot be expected immediately in such cases. There is a problem.

There is also an air conditioner that is equipped with an auxiliary electric heater and uses the auxiliary electric heater to heat the engine until the temperature of the engine coolant rises. It has the disadvantage of being easily damaged.

In addition, we have developed an air conditioner that can be used as a heat pump by switching the cooling refrigeration system (Japanese Patent Application Laid-open No.
No. 38113) is also known, but since this uses exhaust gas as a heat source, the heat exchanger must be constructed to withstand high temperatures and oxidation, and it also requires safety against exhaust gas. Since the air conditioner must have an airtight structure that takes into account the nature of the air conditioner, it has the disadvantage that the configuration of the air conditioner becomes more complicated.

(Purpose of the invention) The present invention was made in view of the above circumstances, and is a vehicle equipped with a refrigeration system for cooling the room and a hot water heating system that heats the room using the engine water temperature. In a commercial air conditioner, when the outdoor temperature is within a predetermined range from 0°C to 15°C, and the engine water temperature is lower than the predetermined temperature determined in consideration of the heating efficiency of the hot water heating system. When the temperature is low, the cooling refrigeration system can be operated as a heat pump to immediately produce a heating effect without making any major changes to the configuration, and the heating efficiency of the hot water heating system is comparable to that for cooling. If the heating efficiency is higher than the heating efficiency of operating the refrigeration system as a heat pump, the system will prevent the cooling refrigeration system from continuing to operate as a heat pump with low heating efficiency while the hot water heating system performs efficient heating. An object of the present invention is to provide a vehicle air conditioner that can prevent such problems.

(Means for Solving Problems) The characteristics of the vehicle air conditioner according to the present invention include: a cooling refrigeration system for indoor cooling, and a hot water heating system that heats the room using engine water temperature. and wherein the cooling refrigeration device is composed of at least a compressor, a condenser, an expansion valve, and an evaporator, which are connected in order through a cooling refrigerant pipe, wherein between the compressor and the condenser, A compressor discharge direction switching valve and a condenser inflow direction switching valve are provided in order from the upstream side of the refrigerant pumping direction of the compressor in the existing cooling refrigerant pipe, and the cooling refrigerant pipe existing between the condenser and the evaporator is provided with a compressor discharge direction switching valve and a condenser inflow direction switching valve. A condenser outflow direction switching valve and an evaporator inflow direction switching valve are provided in order from the upstream side in the refrigerant pumping direction of the compressor, and a cooling refrigerant pipe existing between the evaporator and the compressor is provided on the upstream side in the refrigerant pumping direction of the compressor. An evaporator outflow direction switching valve and a compressor inflow direction switching valve are provided in this order, and in order to perform heating and cooling by the cooling refrigeration device, between the compressor discharge direction switching valve and the evaporator inflow direction switching valve, the evaporator Each heating refrigerant pipe connects between the outflow direction switching valve and the condenser inflow direction switching valve, and between the condenser outflow direction switching valve and the compressor inflow direction switching valve, and each of the switching valves is connected to the cooling direction switching valve. a control circuit that performs switching control between a refrigerant pipe for heating and a refrigerant pipe for heating; When the temperature is lower than a predetermined temperature determined in consideration of the heating efficiency of the device, the refrigerant flowing out from the compressor is connected to the condenser in order to operate the cooling refrigeration device as a heat pump by a passenger's manual switch operation. The refrigerant that flows into the condenser via the cooling refrigerant pipe between the compressor and the condenser flows into the evaporator via the expansion valve of the cooling refrigerant pipe between the evaporator and the condenser. From a state in which refrigerant flows into the evaporator and can circulate to the compressor through the cooling refrigerant pipe between the compressor and the evaporator, the refrigerant flows out from the compressor into the compressor discharge direction switching valve. The refrigerant flows into the evaporator through the heating refrigerant pipe between the evaporator inflow direction switching valve and the heating refrigerant pipe between the evaporator outflow direction switching valve and the condenser inflow direction switching valve. The refrigerant flowing into the condenser through an expansion valve in the condenser and flowing out of the condenser is circulated through a heating refrigerant line between the condenser outflow direction switching valve and the compressor inflow direction control valve and flowing into the compressor. The configuration is such that each of the switching valves is controlled in the state shown in FIG.

(Function) According to this vehicle air conditioner, when the outdoor temperature is within a predetermined range and the engine water temperature is below a predetermined temperature, the switching valve is switched from the cooling refrigerant pipe side to the heating refrigerant pipe side. When switched to the road side, the refrigerant flows through the heating pipe, and the evaporator during cooling functions as a condenser, and the condenser during cooling functions as an evaporator. Even if the heating effect of the heating device cannot be expected immediately, the room can be heated using the cooling refrigeration device.

(Example) Examples of the vehicle air conditioner according to the present invention will be described below with reference to the drawings.

In FIG. 1, numeral 1 indicates a cooling refrigeration device for indoor cooling, and numeral 2 indicates a hot water type heating device. The hot water heating device 2 is roughly composed of an engine 3, a radiator 47 for cooling the engine, a cooling water pipe 4, a heat exchanger 5 as a hot water heater, and a fan 6 for blowing air. When the engine cooling water passes through the engine 3, it receives heat from the engine 3 and is guided to the heat exchanger 5. The fan 6 takes in outside air or inside air and passes it through the heat exchanger 5. It has the function of blowing air into the room. The outside air or inside air is heated by receiving heat from the engine cooling water through the heat exchanger 5, and is led into the room as warm air, thereby heating the room. In addition, after passing through the heat exchanger 5, the engine cooling water is guided to the radiator 47, radiates its heat to the outside air, is cooled, and returns to the engine 3.
It is guided by.

The cooling refrigeration device 1 is of a heat pump type that has an indoor cooling system 7 and an indoor heating system 8 and performs indoor heating and cooling. This cooling refrigeration device 1
can be switched between the indoor cooling system 7 and the indoor heating system 8. That is, the cooling refrigeration device 1
has a compressor 9, a condenser 10, a fan 11, a liquid tank 12, and an evaporator 13, and an indoor cooling system 7 and an indoor heating system 8.
means this compressor 9, capacitor 10, evaporator 13, fan 11, liquid tank 1
2 are shared. The compressor 9, the condenser 10, the liquid tank 12, and the evaporator 13 are connected in order through cooling refrigerant pipes 14, 15, 16, and 17, and an expansion valve 18 is provided in the middle of the cooling refrigerant pipe 16. The expansion valve 18 has the function of converting a high-pressure, high-temperature liquid refrigerant into a low-pressure, low-temperature liquid refrigerant, and the condenser 10 cools the high-pressure, high-temperature refrigerant to a condensation point, converting it from gas to high-pressure liquid. Evaporator 13
has the function of evaporating a liquid refrigerant to remove heat from the internal air and converting it into a gaseous refrigerant.

Each of the cooling refrigerant pipes 14, 15, 16, and 17 is provided with a switching valve. These switching valves are, from the upstream side of the compressor 9 in the refrigerant pumping direction, a first switching valve 19, a second switching valve 20, a third switching valve 21, and a fourth switching valve.
switching valve 22, fifth switching valve 23, sixth switching valve 24,
A seventh switching valve 25 is provided in this order. A cooling refrigerant pipe 14 existing between the compressor 9 and the condenser 10 is provided with a first switching valve 19 which is a compressor discharge direction switching valve and a second switching valve 20 which is a condenser inflow direction switching valve. The cooling refrigerant pipe 15 existing between the compressor 10 and the liquid tank 12 has a third switching valve 21 which is a condenser outflow direction switching valve and a fourth switching valve which is a liquid tank inflow direction switching valve in order from the upstream side of the compressor 9 in the refrigerant feeding direction. A switching valve 22 is provided, and the cooling refrigerant pipe 16 that exists between the liquid tank 12 and the evaporator 13 is provided with a fifth switching valve 23, which is a liquid tank outflow direction switching valve, and a fifth switching valve 23, which is a liquid tank outflow direction switching valve, in order from the upstream side in the refrigerant feeding direction of the compressor. A sixth switching valve 24 which is an inflow direction switching valve is provided, and an evaporator outflow direction switching valve is provided in the cooling refrigerant pipe 17 existing between the evaporator 13 and the compressor 9 in order from the upstream side of the compressor 9 in the refrigerant feeding direction. A seventh switching valve 25 which is a switching valve for the compressor inflow direction and an eighth switching valve 26 which is a compressor inflow direction switching valve are provided. Note that the sixth switching valve 24 is disposed between the expansion valve 18 and the evaporator 13. Then, the first switching valve 19 and the sixth switching valve 24 are connected by the first heating refrigerant pipe line 27, and the seventh switching valve 25 and the sixth switching valve 24 are connected to each other so that the cooling refrigeration device 1 can perform heating. 4 switching valve 22 and the second heating refrigerant pipe line 2
8, the fifth switching valve 23 and the second switching valve 20
are connected by a third heating refrigerant pipe 29, and the third switching valve 21 and the eighth switching valve 26 are connected by a fourth heating refrigerant pipe 30. When cooling the vehicle,
The refrigerant is connected to the cooling refrigerant pipes 14 to 17 by arrows A to H.
When the vehicle is heated,
The refrigerant is connected to heating refrigerant pipes 27 to 30 by arrows I to T.
It is something that is circulated in the same direction. An expansion valve 31 is provided upstream of the condenser 10.
1 has the function of converting high-pressure room temperature refrigerant into low-pressure low-temperature refrigerant during indoor heating, and condenser 1 during cooling.
During heating, the evaporator 13 evaporates the refrigerant and removes the heat from the outside air. During heating, the evaporator 13 cools the high-pressure, high-temperature refrigerant to the condensation point during heating, radiates the heat, and converts it into high-pressure liquid. Functions as a capacitor for the source.

FIG. 2 shows an indoor heating control circuit when heating is performed by the refrigeration cooling device 1, and in this figure, 32 is an indoor heating setting switch. This indoor heating setting switch 32 includes a movable contact 33 and fixed contacts 34 and 35. When the movable contact 33 is switched to the fixed contact 34 side, the heating system 8 becomes operational, and when the movable contact 33 is switched to the fixed contact 35 side, the heating system 8 is turned off. The indoor heating control circuit includes a series circuit 39 consisting of outdoor temperature detection sensors 36, 37 that detect outdoor temperature and an engine water temperature detection sensor 38 that detects engine water temperature. The outdoor temperature detection sensor 36 turns off when the outdoor temperature becomes 0°C or less, and turns on when the outdoor temperature becomes 0°C or more.The outdoor temperature detection sensor 37 turns off when the outdoor temperature becomes 15°C or more, and turns off when the outdoor temperature reaches 15°C. The engine water temperature detection sensor 38 turns on when the engine water temperature falls below 40°C, which is a predetermined temperature determined in consideration of the heating efficiency of the hot water heating system.
It turns off when the temperature exceeds 40℃. The series circuit 39 is connected to a relay 40 and a relay 41, and the relay 40 has a function of switching and driving the switching valves 19 to 26 of the cooling refrigeration system 1 as a load 42, and when the outdoor temperature ranges from 0°C to 15°C. ℃ and when the engine water temperature is below 40℃,
The coil 43 is energized, the normally open contact 44 is closed, the load 42 is energized, and the switching valve 1 as a load is energized.
9 to 26 are switched to the indoor heating system 8 side,
The refrigerant circulates through the heating refrigerant pipes 27 to 30, and the heating system 8 operates. At this time, the coil 45 of the relay 41 is energized, its normally open contact 46 is closed, and the compressor 9, fan 11, etc. of the cooling refrigeration system 1 are energized. This is a flowchart for explaining the activation and deactivation of the heating system 8 of the device 1.

The flow of refrigerant in the cooling refrigeration system is shown in Figure 4 below.
This will be explained in detail with reference to FIG.

(1) When operating a cooling refrigeration device as a cooling device.

The switch 33 shown in FIG. 2 is a fixed contact 35.
When the cooling refrigeration system is driven when the refrigerant is on the side shown in FIG.
The refrigerant flows through the cooling refrigerant pipe 14 in the direction of arrow B, and flows into the condenser 10 through the second switching valve 20 in the direction of arrow B. The condenser 10 cools the high-temperature, high-pressure refrigerant flowing out from the compressor 9 into a low-temperature, high-pressure refrigerant. The refrigerant flowing out of the condenser 10 flows in the direction of arrow C.
The refrigerant flows through the cooling refrigerant pipe 15 through the switching valve 21, passes through the fourth switching valve 22 in the direction of arrow D, and flows into the liquid tank 12. The refrigerant flowing out of the liquid tank 12 passes through the fifth switching valve 23 in the direction of arrow E, flows through the cooling refrigerant pipe 16, and flows into the expansion valve 18. This expansion valve 18
Accordingly, a low-temperature, high-pressure refrigerant is treated as a low-temperature, low-pressure refrigerant. The refrigerant flowing out of the expansion valve 18 passes through the sixth switching valve 24 in the direction of arrow F and flows into the evaporator 13. This evaporator 13
The room is cooled by the low-temperature, low-pressure refrigerant that flows into the room. The refrigerant flowing out from the evaporator 13 passes through the seventh switching valve 25 in the direction of arrow G, flows through the cooling refrigerant pipe 17, and then flows through the eighth switching valve 25.
6 in the direction of arrow H, flows into compressor 9, and is circulated.

The switch 33 shown in FIG. 2 is a fixed contact 34.
Even if the outdoor temperature detection sensor 36,
37. When at least one of the engine water temperature detection sensors 38 is off (when the outdoor temperature is between 0°C and 15°C)
(or when the engine water temperature is above 40°C), the switching valves 19 to 26 remain as they are, and when the cooling refrigeration system is driven, the refrigerant flows in the same direction.

(2) When operating a cooling refrigeration device as a heat pump.

When the switch 33 is on the side of the fixed contact 34 and the outdoor temperature detection sensors 36, 37 and the engine water temperature detection sensor 38 are on (the outdoor temperature is between 0°C and 15°C)
℃ and the engine water temperature is within the specified range.
(when the temperature is below 40°C), the switching valves 19 to 26 are switched. Further, the compressor 9, fan 11, etc. are automatically driven. Therefore, as shown in FIG. 5, the refrigerant flowing out of the compressor 9 passes through the first switching valve 19 in the direction of arrow I, flows through the first heating refrigerant pipe 27 in the direction of arrow J, and then passes through the sixth switching valve 24.
flows in the direction of arrow K into the evaporator 13. The high-temperature, high-pressure refrigerant is cooled by this evaporator 13, and the heat of the refrigerant is radiated.
It becomes a low-temperature, high-pressure refrigerant. This heats the room. The refrigerant flowing out from the evaporator 13 passes through the seventh switching valve 25 in the direction of the arrow L, flows through the second heating refrigerant pipe 28 in the direction of the arrow M, passes through the fourth switching valve 22 in the direction of the arrow N, and is transferred to the liquid tank 12.
flows into. The refrigerant flowing out from the liquid tank 12 passes through the fifth switching valve 23 in the direction of arrow O, flows through the third heating refrigerant pipe 29 in the direction of arrow P, and then flows through the expansion valve 3.
Flows into 1. This expansion valve 31 turns the high-pressure, normal-temperature refrigerant into a low-pressure, low-temperature refrigerant. This expansion valve 31
The low-temperature, low-pressure refrigerant flowing out passes through the second switching valve 20 in the direction of arrow Q and flows into the condenser 10. With this condenser 10, the low-temperature, low-pressure refrigerant absorbs heat from the outside air and becomes a high-temperature, normal-pressure refrigerant. The refrigerant flowing out of the condenser 10 passes through the third switching valve 21 in the direction of arrow R, flows through the fourth heating refrigerant pipe 30 in the direction of arrow S, passes through the eighth switching valve 26 in the direction of arrow T, and flows into the compressor 9. , circulate.

(Effects of the invention) Since the present invention is constructed as described above, it has the following effects.

Without significantly changing the configuration of a vehicle air conditioner equipped with a conventional hot water heating system and a cooling refrigeration system, the engine water temperature can be lower than a predetermined temperature determined in consideration of the heating efficiency of the hot water heating system. When the outdoor temperature is within a specified range from 0℃ to 15℃ (i.e., when the outdoor temperature is within a specified range from 0℃ to 15℃ (i.e.,
(If you are in a temperature range where you feel the need for warm air during the intermediate seasons such as spring or autumn, but you cannot expect the heating effect immediately)
By operating the conventional cooling refrigeration equipment as a heat pump,
When the heating effect can be expected immediately, and when the engine water temperature is above the specified temperature, the hot water heating system performs efficient heating, while the cooling refrigeration system performs its original function. Since the switching valve is used to switch to a system that performs the cooling function, it is possible to prevent the cooling refrigeration system from continuing to operate as a heat pump with low heating efficiency.

When the outdoor temperature is above a predetermined temperature, each switching valve switches the cooling refrigeration system to the system that performs its original cooling function, so even if the switch is operated carelessly, the cooling refrigeration system will not operate as a heat pump. Therefore, warm air may be blown into the room due to careless switch operation.
It also prevents the occupants from feeling uncomfortable.

When the outdoor temperature is 0° C. or lower, the cooling refrigeration device does not operate as a heat pump, so it is possible to prevent the fins of the evaporator and the condenser from freezing.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a vehicle air conditioner according to the present invention, FIG. 2 is an indoor heating control circuit diagram for operating the heating system of the refrigeration cooling device shown in FIG. 1, and FIG. A flowchart for explaining the operation of the heating system of the cooling refrigeration device shown in FIG.
FIG. 4 is an explanatory diagram of the flow of refrigerant when the cooling refrigeration device is operated as a cooling device, and FIG. 5 is an explanatory diagram of the flow of refrigerant when the cooling refrigeration device is operated as a heat pump. 1... Cooling refrigeration device, 2... Hot water heating device, 3... Engine, 9... Compressor, 10
... Capacitor, 12 ... Liquid tank, 13
... Evaporator, 14-17... Refrigerant pipe line for cooling, 19-26... Switching valve, 27-30... Refrigerant pipe line for heating.

Claims (1)

[Scope of Claim for Utility Model Registration] The invention has a cooling refrigeration device for indoor cooling and a hot water heating device that heats the room using engine water temperature, and the cooling refrigeration device is a cooling refrigerant pipe. In a vehicle air conditioner comprising at least a compressor, a condenser, an expansion valve, and an evaporator connected in sequence, a cooling refrigerant pipe existing between the compressor and the condenser is connected upstream of the compressor in a refrigerant pumping direction. A compressor discharge direction switching valve and a condenser inflow direction switching valve are provided in order from the side, and a condenser outflow direction switching valve is provided in order from the upstream side of the refrigerant pumping direction of the compressor in a cooling refrigerant pipe existing between the condenser and the evaporator. and an evaporator inflow direction switching valve, and an evaporator outflow direction switching valve and a compressor inflow direction switching valve are installed in a cooling refrigerant pipeline existing between the evaporator and the compressor in order from the upstream side in the refrigerant pumping direction of the compressor. and between the compressor discharge direction switching valve and the evaporator inflow direction switching valve, and between the evaporator outflow direction switching valve and the condenser inflow direction switching valve, in order to perform heating and cooling by the cooling refrigeration device. The condenser outflow direction switching valve and the compressor inflow direction switching valve are connected by respective heating refrigerant pipes, and each of the switching valves is connected between the cooling refrigerant pipe and the heating refrigerant pipe. The control circuit includes a control circuit that performs switching control, and the control circuit is configured to perform switching control when the outdoor temperature is within a predetermined range from 0°C to 15°C and the engine water temperature is lower than a predetermined temperature determined in consideration of the heating efficiency of the hot water heating device. In order to operate the cooling refrigeration system as a heat pump by a passenger's manual switch operation when the temperature is low, the refrigerant flowing out from the compressor is passed through the cooling refrigerant pipe between the condenser and the compressor. The refrigerant flowing into the condenser and flowing out from the condenser flows into the evaporator via the expansion valve of the cooling refrigerant pipe between the evaporator and the condenser, and the refrigerant flowing out from the evaporator flows between the compressor and the evaporator. The refrigerant flowing out from the compressor is allowed to circulate to the compressor through the cooling refrigerant pipe between the compressor and the heating refrigerant pipe between the compressor discharge direction switching valve and the evaporator inflow direction switching valve. The refrigerant flowing into the evaporator through the evaporator and flowing out from the evaporator flows into the condenser through the expansion valve of the heating refrigerant pipe between the evaporator outflow direction switching valve and the condenser inflow direction switching valve, and flows from the condenser into the condenser. Each of the switching valves is controlled so that the refrigerant that flows out can circulate into the compressor through a heating refrigerant pipe between the condenser outflow direction switching valve and the compressor inflow direction switching valve. A vehicle air conditioner featuring: