JPH06135221A - Air conditioner - Google Patents

Abstract

PURPOSE:To realize use even under the environment of extremely low temperature without causing power shortage and safety reduction in a case in which an auxiliary heating system to complement the heating capability of a main heating system is provided. CONSTITUTION:Inside a duct 11, a heat exchanger 6 of a freezing cycle 1 is provided and at the same time a warm water heater 13 to which the cooling water of an engine 12 is supplied is provided. At the freezing cycle 1, a hot gas feed mechanism 17 to feed hot gas that is from a compressor 2 to the heat exchanger 6 at the time of heating operation is provided, and in addition, at this hog gas feed mechanism 17, an endothermic heat exchanger 23 is provided by positioning it downstream of the heat exchanger 6, and this endothermic heat exchanger 23 is arranged at the exhaust opening 24 of a vehicle room 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner suitable for mounting on a vehicle.

[0002]

2. Description of the Related Art For example, as a heating device in an air conditioner mounted on a vehicle, a device utilizing waste heat of an engine for driving the vehicle has become mainstream, and more specifically, a cooling device for cooling the engine. A hot water heater in which water flows is used, and the hot water heater is arranged downstream of the heat exchanger of the refrigerating cycle for cooling with respect to the flow of air introduced into the vehicle interior.

However, when the amount of heat generated by the engine is low and the cooling water for cooling the engine is not sufficiently heated, the heating capacity is insufficient with only the hot water heater as the main heating device. Therefore, it is considered to use an electric heater, a combustion heater, a heat pump, or the like as the auxiliary heating device.

[0004]

The conventional structure using an electric heater as an auxiliary heating device has a problem of power shortage, and the structure using a combustion heater has a problem that safety is apt to be lowered. The configuration using the heat pump has a problem that it is difficult to use it in a low temperature environment.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent power shortage and decrease in safety when supplementing the heating capacity of a main heating device.
It is to provide a simple air conditioner that can be sufficiently used even in a low temperature environment.

[0006]

The air conditioner of the present invention is provided with a main heating device, and during cooling operation, the refrigerant compressed by the compressor is condensed by the condenser and supplied to the heat exchange equipment. After evaporation, a refrigeration cycle is provided so as to be returned to the compressor, and during heating operation, the refrigerant compressed by the compressor is supplied to the heat exchange device by bypassing the condenser, After radiating heat, a hot gas supply mechanism for returning to the compressor is provided in the refrigeration cycle,
The hot gas supply mechanism is characterized in that it is provided with an endothermic portion that exchanges heat with external heat.

[0007]

According to the air conditioner of the present invention, during heating operation,
Since the high-temperature and high-pressure refrigerant or hot gas compressed by the compressor is supplied to the heat exchanger, the heat exchanger radiates heat to supplement the heating capacity of the main heating device. In this case, since the hot gas supply mechanism is provided with the heat absorbing portion that exchanges heat with the external heat, the refrigerant in the hot gas supply mechanism is heated, and the amount of heat released by the heat exchanger is increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. First, the overall configuration will be described with reference to FIGS.

The refrigeration cycle 1 comprises a compressor 2, a condenser 3,
A receiver 4, an expansion valve 5, a heat exchanger 6 and an accumulator 7 are provided. The discharge port of the compressor 2 is connected to the inflow end of the condenser 3 via the solenoid valve 8 and the condenser 3
Is connected to the inflow end of the heat exchanger 6 via the receiver 4 and the expansion valve 5, and the outflow end of the heat exchanger 6 is connected to the suction port of the compressor 2 via the solenoid valve 9 and the accumulator 7. Connected to the department. In this case, the heat exchanger 6 of the refrigeration cycle 1 is, as shown in FIG.
It is arranged in a duct 11 that blows air into the air. The heat-sensitive cylinder 5 a of the expansion valve 5 is arranged on the outflow end side of the heat exchanger 6.

As shown in FIG. 2, the compressor 2 of the refrigeration cycle 1 is driven by an engine 12 for driving a vehicle. A hot water heater 13 as a main heating device is arranged in the duct 11 at a position downstream of the heat exchanger 6. The cooling water outlet of the engine 12 is connected to the inflow end of the warm water heater 13 via a pipe 15 having a water valve 14, and the outflow end of the warm water heater 13 is connected to the cooling water flow of the engine 12 via a pipe 16. It is connected to the entrance.

The hot gas supply mechanism 17 is for supplying a high temperature and high pressure refrigerant, that is, hot gas from the compressor 2 to the heat exchanger 6, and is constructed as follows. That is,
The discharge port of the compressor 2 is connected to the bypass pipe 1 via the solenoid valve 18.
9, the other end of the bypass pipe 19 is connected to the inlet of the pressure reducing valve 20, and the outlet of the pressure reducing valve 20 is connected to the inlet end of the heat exchanger 6 via the bypass pipe 21. Are linked to. Then, in parallel with the solenoid valve 9, the solenoid valve 22
An endothermic heat exchanger 23, which is an endothermic portion, is connected in series. In this case, the heat absorbing heat exchanger 23 of the hot gas supply mechanism 17 is arranged at the exhaust port 24 portion for discharging the air in the vehicle interior 10, as shown in FIG.

Now, the electrical configuration will be described with reference to FIG. The operation unit 25 is an EC which is a control means for controlling a start signal and a stop signal of the cooling operation and a start signal and a stop signal of the heating operation.
It is designed to be input to U26. And the ECU 2
Based on a signal from the operation section 25, 6 controls the solenoid valves 8 and 9, the water valve 14, the solenoid valves 18 and 22, and the electromagnetic clutch 2a to switch on and off, as will be described later. . The electromagnetic clutch 2a is built in the compressor 2, and when energized, the driving force of the engine 12 is transmitted to the compressor 2 to operate the compressor 2.

Next, the operation of this embodiment will be described with reference to FIGS. 4 and 5. In this case, points a to e in the Mollier diagram shown in FIG. 5 indicate the same positions as points a to e in the refrigeration cycle 1 and the hot gas supply mechanism 17 shown in FIG.

When the cooling operation start signal is given to the ECU 26 from the operation unit 25, the ECU 26 energizes the solenoid valves 8 and 9 to open them (see FIG. 4) and energizes the electromagnetic clutch 2a. Then, the operation of the compressor 2 is started. As a result, the high-temperature and high-pressure gas refrigerant compressed by the compressor 2 (point a in the broken line in FIG. 5) is supplied to the condenser 3 via the solenoid valve 8 and condensed there to become the high-temperature and high-pressure liquid refrigerant (see FIG. 5 point a ') of the broken line, this liquid refrigerant is supplied to the expansion valve 5 via the receiver 4 and becomes a low-pressure low-temperature gas-liquid mixed refrigerant here (point c of the broken line in FIG. 5).

Further, the gas-liquid mixed refrigerant from the expansion valve 5 evaporates in the heat exchanger (evaporator) 6 to become a low-temperature low-pressure gas refrigerant (point d of the broken line in FIG. 5). After passing through the valve 9 (point e of the broken line in FIG. 5), it returns to the compressor 2 via the accumulator 7. Therefore, the behavior of the refrigerant in this case is as shown in the diagram A of the broken line in FIG.

During such cooling and heating operation, E
The CU 26 energizes the water valve 14 to open it, so that the cooling water that has cooled the engine 12 is supplied to the hot water heater 13. And
As shown in FIG. 1, an air mix damper 27 is provided in the duct 11, and the air mix damper 27 is provided.
Is adjusted to adjust the ratio between the cool air flowing through the heat exchanger 6 toward the air outlet 11a and the hot air flowing through the hot water heater 13 toward the air outlet 11a. The temperature of the blown air is adjusted. or,
When the air mix damper 27 is adjusted to the "maximum cooling operation", the ECU 26 disconnects the water valve 14 so as to close it, and the cooling water for the engine 12 is not supplied to the hot water heater 13.

When a heating operation start signal is given to the ECU 26 from the operation unit 25, the ECU 26 energizes and opens the solenoid valves 18 and 22 (see FIG. 4).
), The electromagnetic clutch 2a is energized to start the operation of the compressor 2, and further, the water valve 14 is energized to open. Therefore, by opening the water valve 14, the cooling water for cooling the engine 12 is supplied to the hot water heater 13.

Further, by operating the compressor 2, the high-temperature and high-pressure gas refrigerant, that is, the hot gas from the compressor 2 (point a in the solid line in FIG. 5) is supplied to the pressure reducing valve 20 via the solenoid valve 18 and is reduced in pressure. It becomes a high temperature gas refrigerant at a relatively low pressure (points b and c in the solid line in FIG. 5). The gas refrigerant from the pressure reducing valve 20 is radiated by the heat exchanger (radiator) 6 and becomes a low-temperature gas refrigerant containing a small amount of liquid (point d in the solid line in FIG. 5). As understood from the above, the hot gas from the compressor 2 bypasses the condenser 3, the receiver 4 and the expansion valve 5, and the heat exchanger 6
Will be supplied to.

The air flowing through the duct 11 toward the air outlet 11a is heated by the heat radiation from the heat exchanger 6, and then is heated by the hot water heater 13 to be blown into the vehicle interior 10 from the air outlet 11a. To be blown out. The passenger compartment 10
Part of the air inside passes through the intake heat exchanger 23 and the exhaust port 2
It is discharged from the outside as exhaust gas.

On the other hand, the gaseous refrigerant passing through the heat exchanger 6 is supplied to the heat absorbing heat exchanger 23 through the electromagnetic valve 22. In the intake heat heat exchanger 23, the refrigerant exchanges heat with the heat of the exhaust gas from the inside of the vehicle interior 10 that is discharged to the outside through the exhaust port 24. As a result, the refrigerant passing through the heat absorbing heat exchanger 23 (point e in the solid line in FIG. 5) has a slightly lower pressure and a higher temperature than the refrigerant at the point d, and this is returned to the compressor 2 via the accumulator 7. Will be Therefore, the behavior of the refrigerant in this case is as shown in the solid line C in FIG.

Now, consider the case where the solenoid valve 22 is closed and the solenoid valve 9 is opened instead (see FIG. 4) in the heating operation as described above. The hot gas from the compressor 2 (point a in the alternate long and short dash line in FIG. 5) is decompressed by the pressure reducing valve 22 to become a low pressure gas refrigerant (points b and c in the alternate long and short dash line in FIG. 5). The heat is dissipated in 6 and becomes a low-temperature low-pressure gas refrigerant (point d of the chain line in FIG.
e), this will be returned to the compressor 2 via the accumulator 7. Therefore, the behavior of the refrigerant in this case is as shown by the dashed line B in FIG.

As is apparent from FIG. 5, when the heat absorbing heat exchanger 23 is not used in the hot gas supply mechanism 17, heat is exchanged for the work Wb of the compressor 2 as shown in the diagram B. Although the heat radiation amount Qb of the container 6 is small, when the heat absorbing heat exchanger 23 is used, as shown in the diagram C, the compressor 2
The heat radiation amount Qc of the heat exchanger 6 is large with respect to the work Wc of the compressor 2 as compared with the case of the diagram B.
The efficiency of the heating capacity for the job will be high.

In the case of the diagram B in which the heat absorbing heat exchanger 23 is not used in the hot gas supply mechanism 17, the work of the compressor 2 is only directly converted into heat, so that the temperature in the vicinity of -20.degree. In a low temperature environment, the temperature and pressure of the refrigerant decrease and the specific volume increases, so the amount (weight) of the refrigerant sucked by the compressor 2 decreases, and therefore the compressor 2 does not perform sufficient work. Therefore, the auxiliary heating capacity may be insufficient.

On the other hand, in the case of the diagram C using the heat absorbing heat exchanger 23 in the hot gas supply mechanism 17, the temperature and pressure of the refrigerant are increased by the heat absorbing action of the heat absorbing heat exchanger 23. Therefore, even in an extremely low temperature environment near -20 ° C, the amount of refrigerant sucked into the compressor 2 will not be insufficient, and the compressor 2 will perform its work sufficiently and fully exert its auxiliary heating capacity. Will be able to.

As described above, according to this embodiment, since the hot gas supply mechanism 17 utilizing the refrigeration cycle 1 is provided as the auxiliary heating device, it is different from the conventional case where the electric heater is used as the auxiliary heating device. Unlike the case where a combustion heater is used, there is no power shortage, and the safety is not reduced. Furthermore, unlike the case where a heat pump is used, it is difficult to use in a low temperature environment. Nothing. Then, in the refrigeration cycle 1, the solenoid valve 18, the bypass pipe 19, the pressure reducing valve 20, and the bypass pipe 2
Since 1 is provided, it can be realized with a simple configuration.

In particular, according to this embodiment, the hot gas supply mechanism 17 is provided with an endothermic heat exchanger 23 for exchanging heat with the heat of the exhaust gas from the passenger compartment 10, and this endothermic heat exchanger. Since the refrigerant from the heat exchanger 6 is heated by 23, the temperature and pressure of the refrigerant can be increased. Therefore, even in an extremely low temperature environment near -20 ° C, the compressor 2
Can perform its work sufficiently without causing insufficient suction of the amount of refrigerant, and can fully exert its auxiliary heating capacity.

In the above embodiment, a temperature sensor for detecting the temperature of the wind from the heat exchanger 6 is provided, and the solenoid valves 22 and 9 are operated according to the temperature detected by the temperature sensor during heating operation.
It is also possible to selectively turn off the power.

FIG. 6 shows the second embodiment of the present invention.
The same parts as those of the embodiment of
The different parts will be described.

That is, the electromagnetic valve 9 is connected in parallel with the electromagnetic valve 22 and the heat absorbing pipe 28 serving as a heat absorbing portion in series, and the heat absorbing pipe 28 discharges the exhaust gas from the engine 12 to the outside. The pipe 29 is arranged so as to be able to exchange heat therewith. Therefore, the second embodiment can also obtain the same operational effect as the first embodiment.

7 and 8 show a third embodiment of the present invention. The same parts as those of the first embodiment are designated by the same reference numerals, and different parts will be described below.

That is, in FIG. 7, the outflow end of the heat exchanger 6 is connected to the inflow end of the accumulator 7 via the pipe 30, and instead of the bypass pipe 21 shown in FIG. 2, the engine 12 (see FIG. 1). ) Is provided with an endothermic heat exchanger 31 which is an endothermic part capable of exchanging heat with the heat of the exhaust gas.

Thus, during the heating operation, the compressor 2
Hot gas from (a in solid line in FIG. 8) is decompressed by the pressure reducing valve 20 to become a high temperature and relatively low pressure gas refrigerant (in solid line, b in FIG. 8), which is the heat absorbing heat exchanger 31.
And is heated here by the heat of the exhaust gas from the engine 12 (see FIG. 1), so that it becomes a gas refrigerant at a higher temperature and a lower pressure than at the point b (point c in FIG. 8).

The gas refrigerant from the heat-absorbing heat exchanger 31 is supplied to the heat exchanger (radiator) 6 and radiates heat to become a low-temperature low-pressure gas refrigerant (point e in FIG. 8), which is the pipe 30. Then, it is returned to the compressor 2 via the accumulator 7. Therefore, the behavior of the refrigerant in this case is as shown by the line D in FIG.

According to the third embodiment, in the first embodiment, the heat absorbing heat exchanger 23 is located on the downstream side of the heat exchanger 6 with respect to the flow of the refrigerant, while in the heat absorbing heat exchange. The container 31 is located upstream of the heat exchanger 6 with respect to the flow of the refrigerant, and is different from the first embodiment only, and the same effect as the first embodiment can be obtained.

FIG. 9 shows the fourth embodiment of the present invention.
The same parts as those of the embodiment of
The different parts will be described.

That is, between the heat exchanger 6 and the accumulator 7, instead of the solenoid valves 9 and 22 and the heat absorbing heat exchanger 23, exhaust gas from the passenger compartment 10 (see FIG. 1) or the engine 12 (see FIG. 1) is used. A heat-absorption heat exchanger 32, which is a heat-absorbing portion capable of exchanging heat with the exhaust gas from the air conditioner 1), is provided.

Thus, in the fourth embodiment, the heat exchanger 32 for heat absorption functions as a heat absorber during heating operation and as an evaporator during cooling operation.
Therefore, the effect similar to that of the first embodiment can be obtained by the fourth embodiment. It should be noted that the present invention is not limited to the above-described respective embodiments, and is not limited to, for example, a vehicle air conditioner, and can be applied to all air conditioners including a main heating device and a refrigeration cycle, which do not deviate from the gist. Needless to say, it can be appropriately modified within the range.

[0038]

As described above, the air conditioner of the present invention is provided with the hot gas supply mechanism for supplying the hot gas from the compressor to the heat exchanger by utilizing the refrigeration cycle as the auxiliary heating device. Since the gas supply mechanism is equipped with an endotherm that exchanges heat with the outside heat, it does not cause power shortage or decrease in safety, and it can be used not only in low temperature environments but also in extremely low temperature environments. It has an excellent effect that it can be realized and can be realized with a simple structure.

[Brief description of drawings]

FIG. 1 is an overall schematic configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a refrigeration cycle and a hot gas supply mechanism.

FIG. 3 is a configuration diagram of an electric circuit

FIG. 4 is a diagram showing an open / closed state of a solenoid valve.

[Figure 5] Mollier diagram

FIG. 6 is a view corresponding to FIG. 2 showing a second embodiment of the present invention.

FIG. 7 is a diagram corresponding to FIG. 2 showing a third embodiment of the present invention.

FIG. 8 is a view corresponding to FIG.

FIG. 9 is a diagram corresponding to FIG. 2 showing a fourth embodiment of the present invention.

[Explanation of symbols]

In the drawing, 1 is a refrigeration cycle, 2 is a compressor, 3 is a condenser,
5 is an expansion valve, 6 is a heat exchanger, 8 is a solenoid valve, 12 is an engine, 13 is a hot water heater (main heating device), 17 is a hot gas supply mechanism (auxiliary heating device), 18 is a solenoid valve, and 20 is decompression. Valve, 23 is a heat exchanger for heat absorption (heat absorption part), 26 is EC
U and 28 are heat absorbing pipes (heat absorbing parts), and 31 and 32 are heat absorbing heat exchangers (heat absorbing parts).

Claims (1)

[Claims] 1. A main heating device, and in a cooling operation, a refrigerant compressed by a compressor is condensed by a condenser and supplied to a heat exchanger, where it is evaporated and then returned to the compressor. And a refrigerating cycle provided in this refrigerating cycle, during heating operation, the refrigerant compressed by the compressor is supplied to the heat exchanger by bypassing the condenser, and after radiating heat there, An air conditioner comprising: a hot gas supply mechanism that is returned to the compressor; and a heat absorbing unit that is provided in the hot gas supply mechanism and exchanges heat with external heat.