KR19980042425A - Automotive Air Conditioning System - Google Patents

Abstract

The vehicle air conditioning system includes a compressor, a first condenser, a second condenser, a liquid tank, an expansion valve, and an evaporator connected to each other through a pipe, and the refrigerant flows from the outlet of the compressor to the inlet of the compressor while changing phase. And a first cycle forming a first refrigerant circulation circuit. The first cycle causes the evaporator to act as a cooler in operation. The air conditioning system comprises a second refrigerant circulation circuit comprising a compressor, a second condenser, a liquid tank, an expansion valve and an evaporator connected to each other via a pipe, the refrigerant flowing from the outlet of the compressor to the inlet of the compressor while changing phase. Form. The second cycle causes the condenser to act as a heater and the evaporator to act as a cooler in operation. The first cycle and the second cycle are switched by switch means. The air conditioning system has an air conduit case having an air flow passage provided with a second condenser and an evaporator. The air flow passage is connected to the vehicle interior of the vehicle in the downstream portion. The air conditioning system also includes heater means for heating the return refrigerant flowing in the pipe extending from the outlet of the evaporator to the inlet of the compressor under the operation of the second cycle.

Description

Automotive Air Conditioning System

BACKGROUND OF THE INVENTION The present invention relates generally to an air conditioning system in a motor vehicle, in particular two functional cycles, a cycle for cooling air by actually using the system as a closed refrigeration system, and a heat pump The present invention relates to a double function type automotive air conditioning system having a cycle of dehumidifying while heating air by practical use as a system.

To date, several types of air conditioning systems have been proposed, particularly in the automotive sector. Some of these are of the aforementioned dual functional type.

In a long-haul passenger car such as a one-box type vehicle, a first air conditioning unit that regulates air at the front of the vehicle interior and a second air conditioner that regulates air at the rear of the vehicle interior A so-called dual air conditioning system was also used, including the unit.

These days, in order to take advantage of the dual functional, some of the dual air conditioning systems adopt the principle of the dual functional. That is, for example, the first air conditioning unit includes an evaporator constituting a part of a dual function air conditioning system, and a heater core to which engine coolant is supplied, and the second air conditioning unit is Another evaporator connected to the air conditioning system and a condenser connected in series with the evaporator to serve as a heater.

However, due to the inherent configuration, the dual air conditioning system described above did not satisfy the user. That is, the second air conditioning unit of the system did not provide sufficient warmed air to the rear of the vehicle interior, especially in cold seasons.

It is therefore an object of the present invention to provide a dual functional vehicle air conditioning system which does not have the drawbacks mentioned above.

Another object of the present invention is to provide an improved automotive dual air conditioning system incorporating the principle of dual functional.

It is a further object of the present invention to provide a dual functional improved air conditioning system for an electric vehicle.

1 is a schematic diagram of a one-box type vehicle to which a dual air conditioning system of the present invention is actually applied.

Fig. 2 is a schematic diagram of a circuit of the dual air conditioner system for automobiles which is the first embodiment of the present invention.

3 is a perspective view of an extra heat exchanger employed in the system of the first embodiment;

FIG. 4 is a schematic view similar to FIG. 2, showing a dual air conditioner system for a vehicle, which is a second embodiment of the present invention; FIG.

Fig. 5 is a perspective view of an essential part of the dual air conditioner system of the second embodiment.

FIG. 6 is a schematic view similar to FIG. 2, showing a dual air conditioning system for a vehicle as a third embodiment of the present invention; FIG.

Figure 7 is a schematic diagram of a circuit of a dual functional air conditioning system, which is a fourth embodiment of the present invention suitable for an electric vehicle.

8 is a partial cross-sectional side view of a redundant evaporator employed in the system of the fourth embodiment.

9 is a plan view of a surplus evaporator.

10 is a side view of a surplus evaporator.

11 is a front view of a spiral sheathed heater installed in a redundant evaporator.

12 is a schematic diagram showing a modification of the redundant evaporator usable in the fourth embodiment.

Figure 13 is a schematic diagram of a modification in which some parts are removed.

14 is a schematic view of the right part of a modification.

15 is a schematic view of the left part of a modification.

Fig. 16 is a schematic diagram showing a modification arranged vertically;

Fig. 17 is a block diagram of a control circuit employed in the dual functional air conditioner of the fourth embodiment.

18 is a chart showing on / off characteristics of a spiral sheath heater.

Explanation of symbols for the main parts of the drawings

m: feedback circuit

V1, V2: open / close valve

1: compressor

2: engine

3, 21: condenser

3B, 31: bypass circuit

4a, 4b: liquid tank

5a, 5b: expansion valve

10, 20: air conditioning unit

11: heater core

11a, 11b, 32: open / close valve

12, 22: heat exchanger

30: surplus heat exchanger

Air Conditioning System: 100A, 100B, 100C, 100D

110: air conduit case

138: control unit

According to a first aspect of the invention, a compressor, a first condenser, a second condenser, a liquid tank, an expansion valve, and an evaporator, connected to each other via a pipe, comprises a compressor from the outlet of the compressor with the refrigerant changing phases. A first cycle for forming a first refrigerant circulation circuit which flows to an inlet of the first refrigerant, causing the evaporator to act as a cooler during operation; Forming a second refrigerant circulation circuit comprising a compressor, a second condenser, a liquid tank, an expansion valve, and an evaporator, connected to one another via a pipe, wherein the refrigerant flows from the outlet of the compressor to the inlet of the compressor while changing phases; A second cycle of causing the condenser to act as a heater and the evaporator to act as a cooler; Switch means for switching between a first cycle and a second cycle; An air conduit case provided with a second condenser and an evaporator and having an air flow passage connected to a vehicle interior of the vehicle in a downstream portion; A vehicle air conditioning system is provided comprising heater means for heating a return refrigerant flowing in a pipe extending from the outlet of the evaporator to the inlet of the compressor under the operation of the second cycle.

According to a second aspect of the invention there is provided a dual air conditioning system for a motor vehicle powered by an internal combustion engine. The dual air conditioning system includes a compressor, a first condenser, a first liquid tank, a first expansion valve, and a first heat exchanger, driven by internal combustion engines connected to each other via pipes, from the outlet of the compressor with the refrigerant changing phases. A first cycle that forms a first refrigeration circuit that flows to the inlet of the compressor, and includes a compressor, a liquid tank, a second condenser, a second liquid tank, a second expansion valve, and a second heat exchanger connected to each other via a pipe; A second cycle for forming a second refrigeration circuit in which the refrigerant flows from the outlet of the compressor to the inlet of the compressor while changing phases, and a first switch for switching between the first cycle and the second cycle; A first system for operating the first heat exchanger and the second heat exchanger as a cooler; A third cycle comprising the same components as the first cycle except the first condenser, a fourth cycle comprising the same components as the second cycle except the first condenser, and a third cycle and the fourth cycle A second system comprising a second switching means for switching, the second system acting as a cooler and a second condenser as a heater; A heater core into which hot water from the water jacket of the internal combustion engine is introduced; An air conduit case having a first air flow passage provided with a heater core and a first heat exchanger, and a second air flow passage provided with a second condenser and a second heat exchanger; Heater means for heating a return refrigerant that is about to enter the inlet of the compressor under operation of the second system; Each of the first air flow passage and the second air flow passage is connected to the vehicle interior of the vehicle in the downstream portion.

According to a third aspect of the invention there is provided a dual air conditioning system for a motor vehicle powered by an internal combustion engine. The air conditioning system includes a compressor, a first condenser, a first liquid tank, a first expansion valve, and a first heat exchanger, driven by internal combustion engines connected to each other via pipes, with refrigerant flowing from the outlet of the compressor to the inlet of the compressor. A first cycle of forming a first refrigerant circulation circuit, the first heat exchanger acting as a cooler during operation; A second refrigerant circulation circuit comprising a compressor, a second condenser, a second liquid tank, and a second expansion valve connected to each other via a pipe, the refrigerant flowing from the outlet of the compressor to the inlet of the compressor, the second being in operation A second cycle of causing the condenser to act as a heater; Switch means for switching between a first cycle and a second cycle; A heater core into which hot water from the water jacket of the internal combustion engine is introduced; An air conduit having a first air flow passage provided with a heater core and a first heat exchanger, and a second air flow passage provided with a second condenser; Heater means for heating a return refrigerant that is about to enter the inlet of the compressor under operation of a second cycle; Each of the first air flow passage and the second air flow passage is connected to the vehicle interior of the vehicle in the downstream portion.

According to the 4th aspect of this invention, the air conditioning system for electric vehicles is provided. The air conditioning system comprises a compressor, a first condenser, a second condenser, a liquid tank, an expansion valve, and an evaporator, driven by electric motors connected to each other via a pipe, the inlet of the compressor from the outlet of the compressor with the refrigerant changing phases. A first cycle for forming a first refrigerant circulation circuit, the first cycle allowing the evaporator to act as a cooler during operation; A compressor comprising a compressor, a second heat exchanger, a liquid tank, an expansion valve, and an evaporator connected to each other via a pipe, forming a second refrigerant circulation circuit in which the refrigerant flows from the outlet of the compressor to the inlet of the compressor while changing phase, and operates A second cycle of causing the condenser to act as a heater and the evaporator to act as a cooler; Switch means for switching between a first cycle and a second cycle; An air conduit case provided with a second condenser and an evaporator and having an air flow passage connected to a vehicle interior of the electric vehicle in a downstream portion; Heater means for heating the return refrigerant flowing in the pipe extending from the outlet of the evaporator to the inlet of the compressor under the operation of the second cycle.

Other objects and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings.

1 to 3, there is shown a dual air conditioner system 100A for automobiles of a first embodiment of the present invention.

As can be seen from FIG. 1, the dual air conditioning system 100A includes a first air conditioning unit 10 mounted at the front of the vehicle V and a second mounted at the rear of the vehicle V. FIG. And an interconnecting means for operatively connecting the air conditioning unit 20 and the first air conditioning unit 10 and the second air conditioning unit 20 in the manner described below. As will be understood from the figure, the first air conditioning unit 10 and the second air conditioning unit 20 are arranged and configured to regulate the air blown into the front and rear portions of the vehicle interior, respectively. That is, the first air conditioner unit 10 selectively takes the outside air (ie, the vehicle outside air) and / or the inside air (ie, the vehicle interior air) to regulate the air before discharging the air to the front of the vehicle interior. On the other hand, the second air conditioner unit 20 takes in the internal air and regulates the air before discharging the air to the rear part of the vehicle interior.

A dual air conditioning system 100A for an automobile is shown schematically in FIG.

As understood from FIG. 2, the first air conditioning unit 10 includes an air intake housing having an air flow passage 10f for causing air to flow in the direction indicated by the arrow. Although not shown in the figure, a suction door and an electric blower are installed upstream of the air flow passage 10f. The first heat exchanger 12 and the heater core 11 are installed in the air flow passage 10f in the manner shown. Although not shown in the figure, the air flow passage 10f has an air vent at a downstream end exposed to the front of the vehicle interior. Although not shown, a known air mixing door is disposed immediately upstream of the heater core 11 to control the ratio in the amount between the hot and cold air supplied to the air mixing chamber, and from the air mixing chamber Controlled air is introduced into the vehicle interior. Typically, the air mixing door may have a position to completely close the air passage for the heater core 11.

Between the heater core 11 and the water jacket of the engine 2, a main hot water flow circuit in which an open / close valve 11a is provided is arranged. That is, when the valve 11a is opened, the warmed engine coolant in the engine water jacket is supplied to the heater core 11.

The second air conditioner unit 20 includes an air intake housing having an air flow passage 20f for causing air to flow in the direction indicated by the arrow. Although not shown in the figure, an electric blower is employed to generate air flow. The second heat exchanger 22 and the second condenser 21 are installed in the manner shown in the air flow passage 20f. Although not shown in the figure, the air flow passage 20f has an air vent at the downstream end exposed to the rear portion of the vehicle interior. A known air mixing door (not shown) is arranged at a position immediately upstream of the second condenser 21 to control the ratio in the amount between the hot air and the cold air supplied to the air mixing chamber, and the air mixing From the chamber, temperature controlled air is introduced into the vehicle interior. Typically, the air mixing door may have a position to completely close the air passage for the second condenser 21.

First closed refrigeration comprising a compressor (1), a first condenser (3), a liquid tank (4a), a first open / close valve (V1), a first expansion valve (5a) and a first heat exchanger (12) A cycle is prepared. The compressor 1 is driven by the engine 2.

In addition to the compressor 1, the first condenser 3 and the liquid tank 4a described above, the second open / close valve V2, the second condenser 21, the liquid tank 4b, the second expansion valve 5b ), A second closed refrigeration cycle is further provided comprising a second heat exchanger (22) and an extra heat exchanger (30).

That is, the outflow line from the liquid tank 4a is divided into two branch pipes to which the first open / close valve V1 and the second open / close valve V2 are respectively connected as shown. The outlet line from the first heat exchanger 12 and the outlet line from the second heat exchanger 22 are joined before being connected to the inlet line of the redundant heat exchanger 30.

In order to achieve not only the heating operation but also the cooling operation, a bypass circuit 3B for bypassing the first condenser 3 is arranged. A two-way valve 7 is provided for switching the first condenser 3 and the bypass circuit 3B. That is, under the heating operation, the compressed refrigerant from the compressor 1 is introduced into the bypass circuit 3B, while under the cooling operation, the refrigerant is introduced into the first condenser 3.

The above switching between the first closed refrigeration cycle and the second closed refrigeration cycle is performed by operating the first open / close valve V1 and the second open / close valve V2.

If desired, a four way valve can be used in place of the two way valve 7. In this case, the feedback circuit m is further provided as shown by the broken line. That is, at the start of the heating operation, the feedback circuit m serves to return a substantial amount of the refrigerant retained in the first condenser 3 to the inlet of the compressor 1.

It should be noted that the excess heat exchanger 30 is disposed outside the air flow passages 10f and 20f of the first air conditioning unit 10 and the second air conditioning unit 20. The excess heat exchanger 30 is shown in detail in FIG. 2, with the excess heat exchanger having a refrigerant passage having an inlet line 30a-1 and an outlet line 30a-2, an inlet line 30b-1 and an outlet line ( Water passages 30b-2). Although not shown in the figure, the refrigerant passage is surrounded by the water passage to achieve effective heat exchange between the refrigerant in the refrigerant passage and the water in the water passage. As shown, the two passages are defined within a housing having a plurality of heat radiation fins (not shown).

Referring again to FIG. 2, the refrigerant inlet line 30a-1 and the refrigerant outlet line 30a-2 of the excess heat exchanger 30 are the outlet lines of the first heat exchanger 12 (thus, the second heat exchanger ( Outlet line 22) and the inlet port of the compressor 1, respectively. The water inflow line 30b-1 and the water outlet line 30b-2 of the surplus heat exchanger 30 pass through the secondary hot water flow circuit Ws and the inflow line and inflow of the main hot water flow circuit Wm described above. Each connected to a line. The open / close valve 11b is installed in the negative hot water flow circuit Ws. That is, when the valve 11b is opened, the warmed engine coolant is supplied to the excess heat exchanger 30 to heat the refrigerant flowing in the heat exchanger 30.

As will be explained in detail later, isotropic compression is effectively carried out by the compressor 1 due to the heating of the returning refrigerant under the heating operation of the air conditioning system. That is, effective heating is achieved by the air conditioning system.

A bypass circuit 31 is provided which bypasses the excess heat exchanger 30 and is provided with an open / close valve 32 therein. Due to the provision of the bypass circuit 31, excessive warming of the return refrigerant is suppressed. That is, by controlling the valve 32, the abnormal discharge pressure of the compressor 1 is suppressed.

In order to control the valve 32, the temperature and pressure of the return refrigerant, the temperature and pressure of the refrigerant discharged from the compressor 1, and the over-heating degree of the return refrigerant can be used as control factors. Various sensors are employed to achieve this control, which are secured to the inlets and outlets of the compressor 1 and to the outlets of the first heat exchanger 12 and the second heat exchanger 22. That is, if at least one of the sensors detects an abnormal condition of the refrigerant, the control unit (not shown) issues a control signal to the valve 32 to open the valve 32.

By detecting the temperature, pressure and superheat of the return refrigerant, undesirable overload of the closed refrigeration system is prevented.

In the following, operation of the dual air conditioning system 100A of the first embodiment will be described.

(1) the initial stage of heating operation

In order to heat both the front part and the rear part of the vehicle interior, the first open / close valve V1 is opened and the second open / close valve V1 is opened, and the valve 7 is the first condenser 3. Switching is made to operate the bypass circuit 3B while closing the circuit.

During operation of the compressor 1, the high temperature and high pressure refrigerant discharged from the compressor 1 is provided with the valve 7, the bypass circuit 3B, the liquid tank 4a, the second open / close valve V2, the second condenser. (21), the liquid tank (4b), the second expansion valve (5b) and the second heat exchanger 22 flows into the excess heat exchanger (30), the refrigerant from the excess heat exchanger (30) is a compressor ( Will return to 1).

During this flow, valves 11a and 11b are both open so that engine coolant is supplied to both heater core 11 and excess heat exchanger 30. Engine coolant gradually increases with time.

Due to the closing condition of the first open / close valve V1, the first heat exchanger 12 does not operate. However, the air flowing in the air flow passage 10f of the first air conditioning unit 10 is somewhat warmed by the heater core 11 to which the somewhat heated engine coolant is supplied. Therefore, the warmed air is blown to the front part of the vehicle interior.

In the second air conditioner unit 20, the high temperature high pressure refrigerant from the compressor 1 is introduced into the second condenser 21 through the second open / close valve V2. Therefore, heat exchange is performed between the air flowing in the air flow passage 20f of the second air conditioner unit 20 and the second condenser 21. After heating the air, the refrigerant having an intermediate temperature and high pressure is adiabaticly expanded in the second expansion valve 5b to become a low temperature low pressure refrigerant, and serves as an evaporator to cool the air flowing in the air flow passage 20f. 2 is introduced into the heat exchanger (22). Then, the low temperature low pressure refrigerant discharged from the second heat exchanger 22 is introduced into the excess heat exchanger 30.

That is, the air flowing in the air flow passage 20f of the second air conditioner unit 20 is cooled by the second heat exchanger 22 and then warmed by the second condenser 21, and thus the second air The conditioning unit 20 supplies regulated (more specifically, dehumidified and warmed) air to the rear of the vehicle interior.

Due to the provision of the excess heat exchanger 3, the heating effect of the second condenser 21 is much increased. That is, the low temperature low pressure refrigerant flowing in the excess heat exchanger 30 absorbs heat from ambient air and engine coolant before being introduced back into the compressor 1. More specifically, before being compressed by the compressor 1, the return refrigerant is warmed up to some level in the second heat exchanger 22 and the excess heat exchanger 30 while changing the entropy of the refrigerant. In other words, before being compressed, the return refrigerant is subjected to two warming stages. Thus, the refrigerant discharged from the compressor 1 can have a higher temperature, and thus the second condenser 21 can exhibit a higher heating effect. This effect becomes remarkable with increasing time.

Thus, instant heating of the rear part of the vehicle interior is achieved.

As time increases, the temperature of the engine coolant from the engine 2 increases, so that the heating effect of the heater core 11 in the air flow passage 10f of the first air conditioning unit 10 gradually increases. . That is, after a while, the second air conditioning unit 10 supplies the warmed air to the front part of the vehicle interior.

(2) stable phase of heating operation

As time increases, both the first air conditioner unit 10 and the second air conditioner unit 20 supply sufficient warmed air to the vehicle interior. At this time, the first open / close valve V1 may also flow the high temperature and high pressure refrigerant from the compressor 1 into the first heat exchanger 12 of the first air conditioning unit 10 through the first expansion valve 5a. To open. Thus, under these conditions, the first heat exchanger 12 serves as an evaporator to cool the air flowing in the air flow passage 10f of the first air conditioning unit 10. That is, the first air conditioner unit 10 supplies air (more specifically, dehumidified and warmed) to the front of the vehicle interior.

Under this stable phase of heating operation, various heating modes are available by controlling the three open / close valves 11a, 11b, 32. Controlling these valves can be accomplished electrically by using a control unit.

(2-1) first mode

This mode is provided by opening valves 11a and 11b and closing valve 32. Under this mode, the warmed coolant from the engine 2 is supplied not only to the heater core 11 through the main hot water flow circuit Wm, but also to the excess heat exchanger 30 through the sub hot water flow circuit Ws. Thus, the first air conditioner unit 10 and the second air conditioner unit 20 can supply dehumidified and warmed air to the vehicle interior.

(2-2) second mode

This mode is provided by opening the valve 11a and closing the valves 11b and 32. Under this mode, due to the opening condition of the valve 11a, the first air conditioning unit 10 can provide dehumidified and warmed air to the front part of the vehicle interior. On the other hand, due to the closing condition of the valve 11b, the excess heat exchanger 30 does not receive warmed engine coolant, more specifically the engine coolant is retained in the excess heat exchanger 30. Thus, for a while, the refrigerant flowing in the excess heat exchanger 30 absorbs heat from the engine coolant retained in the heat exchanger 30. However, with increasing time, the amount of heat possessed by the retained engine coolant gradually decreases. Thus, after a predetermined time has elapsed, the normal heating operation of the dual air conditioning system is provided. That is, in the initial stage of this second mode, relatively hot air is provided by the first air conditioning unit 10 and the second air conditioning unit 20, after which the temperature of the air gradually decreases to the normal high temperature level. do.

(2-3) third mode

This mode is provided by opening valves 11a and 32 and closing valve 11b. In other words, the bypass circuit 31 for the redundancy exchanger 30 is opened. Under this mode, due to the opening condition of the valve 11a, the first air conditioning unit 10 provides dehumidified and warmed air to the front part of the vehicle interior as in the first and second modes described above. On the other hand, due to the closing condition of the valve 11b and the opening condition of the valve 32, the refrigerant from the first heat exchanger 12 and the second heat exchanger 22 is not only bypass circuit 31 but also the excess heat exchanger. It will flow through the device (30). For this reason, the heating effect applied to the refrigerant by the excess heat exchanger 30 is lowered, thus providing a normal heating operation by the dual air conditioning system. By selecting this third mode, the compressor 1 is prevented from generating abnormally high high pressure refrigerant.

It should be noted that the valve 11a remains open under heating operation.

(3) cooling operation

In this cooling operation, three modes are available by controlling the first open / close valve V1 and the second open / close valve V2, namely, the front cooling mode, the dual cooling mode and the rear cooling mode. Under these modes, valves 11a and 11b for warmed engine coolant are closed and valve 32 is open.

(3-1) Front cooling mode

In order to achieve this mode, the valve 7 is switched to a position to operate the first condenser 3 while closing the bypass circuit 3B. Then, the first open / close valve V1 is opened and the second open / close valve V2 is closed. Thus, the high temperature and high pressure refrigerant from the compressor 1 is controlled by the valve 7, the first condenser 3, the liquid tank 4a, the first open / close valve V1, the first expansion valve 5a and the first expansion valve. The first heat exchanger 12 flows to both the excess heat exchanger 30 and the valve 32, and the refrigerant from the excess heat exchanger 30 and the valve 32 returns to the compressor 1. By this circulation of the refrigerant, the first heat exchanger 12 serving as an evaporator cools the air flowing in the air flow passage 10f to provide cooled air in the front part of the vehicle interior.

(3-2) Dual cooling mode

In order to achieve this mode, the valve 7 is switched to a position to operate the first condenser 3 while closing the bypass circuit 3B, and the first open / close valve V1 and the second open / close. Both closing valves V2 are open. As a result, the high temperature and high pressure refrigerant from the compressor 1 flows into the liquid tank 4a through the valve 7 and the first condenser 3, and a part of the refrigerant from the liquid tank 4a is first opened. / Flow through the closing valve (V1), the first expansion valve (5a) and the first heat exchanger (12) to both the excess heat exchanger 30 and the valve 32, the flow of refrigerant from the liquid tank (4a) The other part is the surplus heat exchanger 30 through the second open / close valve V2, the second condenser 21, the liquid tank 4b, the second expansion valve 5b and the second heat exchanger 22 and It will flow to both valves 32. The refrigerant from the excess heat exchanger 30 and the valve 32 is returned to the compressor 1. As a result of this circulation, the first heat exchanger 12 serving as an evaporator cools the air flowing in the air flow passage 10f of the first air conditioning unit 10 and the second heat exchanger serving as an evaporator. Reference numeral 22 cools the air flowing in the air flow passage 20f of the second air conditioner unit 20. Accordingly, the first air conditioner unit 10 and the second air conditioner unit 20 provide cooled air to the front part and the rear part of the vehicle interior. It should be noted that under these conditions, since the refrigerant supplied to the second condenser 21 is already condensed by the first condenser 3, the second condenser 21 does not operate as a condenser.

(3-3) rear cooling mode

In order to achieve this mode, the valve 7 is switched to a position to operate the first condenser 3 while closing the bypass circuit 3B, and the second open / close valve V2 is opened and the first The open / close valve V1 is closed. For this reason, the high temperature high pressure refrigerant | coolant from the compressor 1 is valve | bulb 7, the 1st condenser 3, the liquid tank 4a, the 2nd open / close valve V2, the 2nd condenser 21, and the liquid tank. 4b, the second expansion valve 5b and the second heat exchanger are allowed to flow to both the excess heat exchanger 30 and the valve 32. The refrigerant from the excess heat exchanger 30 and the valve 32 is returned to the compressor 1. As a result of this circulation, the second heat exchanger 22 serving as the evaporator cools the air flowing in the air flow passage 20f of the second air conditioning unit 20. Thus, the second air conditioner unit 20 provides cooled air to the rear portion of the vehicle interior. For the reasons described above, under these conditions, the second condenser 21 does not operate as a condenser.

Referring to Fig. 4, there is shown a dual air conditioning system 100B for a vehicle, which is a second embodiment of the present invention.

The system 100B of the second embodiment is similar to the above-described system 100A of the first embodiment, but only the parts and parts different from the first embodiment will be described in detail below. Parts and parts substantially the same as the system 100A of the first embodiment are denoted by the same reference numerals.

As can be seen from Fig. 4, in the system 100B of the second embodiment, there is no means corresponding to the bypass circuit 31 and the valve 32 used in the system 100A of the first embodiment. Moreover, the excess heat exchanger 30 is arranged in the refrigerant line immediately downstream of the second heat exchanger 22. As shown, the refrigerant line from the outlet of the excess heat exchanger 30 is connected to the refrigerant line extending from the outlet of the first heat exchanger 12 to the compressor 1.

As shown in FIG. 4, in the air conditioning system 100B of the second embodiment, the temperature of the refrigerant immediately discharged from the excess heat exchanger 30 is sensed to control the valve opening of the second expansion valve 5b. The temperature sensor 40 is adopted. That is, as can be seen from FIG. 5, the temperature sensor 40 is mounted on the outlet line 30a-2 of the excess heat exchanger 30. Although not shown in the figure, a known controller is incorporated with the second expansion valve 5b to control the valve opening degree of the second expansion valve 5b according to the information signal generated from the temperature sensor 40.

That is, when the temperature of the refrigerant immediately discharged from the excess heat exchanger 30 is relatively high, the valve opening degree of the second expansion valve 5b is increased, while the temperature is relatively low and the opening degree of the valve 5b is reduced.

As is known, the high temperature of the refrigerant supplied directly to the compressor 1 means that the heat load of the refrigeration cycle is high. Thus, by increasing the valve opening degree of the second expansion valve 5b, the amount of refrigerant returned to the compressor 1 is increased, thereby supplying a larger amount of refrigerant to the second closed refrigeration cycle. By this, proper cooling operation is achieved by the second air conditioner unit 20. On the other hand, when the temperature of the refrigerant from the excess heat exchanger 30 is relatively low, the valve opening of the second expansion valve 5b is reduced to appropriately control the amount of refrigerant flowing in the second closed refrigeration cycle.

The operation of the system 100B of the second embodiment is substantially the same as the operation of the system 100A of the first embodiment described above except for the following.

That is, due to the provision of additional means including a temperature sensor 40 for controlling the valve opening of the second expansion valve 5b, a more precise cooling operation as described above is carried out by the second air conditioning unit 20. do.

Referring to Fig. 6, there is shown a dual air conditioning system 100C for a vehicle, which is a third embodiment of the present invention.

Since the system 100C of this third embodiment is similar to the above-described system 100B of the second embodiment, only parts and components different from the second embodiment will be described in detail below. Parts and parts substantially the same as the system 100B of the second embodiment are denoted by the same reference numerals.

As can be seen from Fig. 6, in the system 100C of the third embodiment, there is no means corresponding to the second heat exchanger 22 used in the system 100B of the second embodiment. That is, the outlet of the second condenser 21 is connected to the inlet line 30a-1 of the excess heat exchanger 30 via the liquid tank 4b and the second expansion valve 5b. Moreover, there is no means corresponding to the additional means (including the temperature sensor 40 for controlling the second expansion valve 5b) employed in the system 100B of the second embodiment.

Moreover, in the system 100C of the third embodiment, the refrigerant line from the outlet of the compressor 1 to the first condenser 3 is provided with a first opening / closing valve Va, and is provided from the outlet of the compressor 1. 2 A second open / close valve Vb is installed in the refrigerant line to the inlet of the condenser 21, and a third open to the refrigerant line from the outlet of the first heat exchanger 12 to the inlet of the liquid tank 4a. A closing valve Vc is installed.

Due to the removal of the second heat exchanger 22 from the second air conditioner unit 20, the second air conditioner unit 20 loses the cooling function. However, the second unit 20 can be made compact, so that the entire air conditioning system 100C of this third embodiment can be made compact.

In the following, operation of the dual air conditioning system 100C of the third embodiment will be described.

(1) heating operation

In order to heat both the front part and the rear part of the vehicle interior, both the valves 11a and 11b are opened, and the first open / close valve Va is closed and then the second open / close valve Vb is opened. . Therefore, engine coolant is supplied to the heater core 11. However, in the initial heating stage, the heater core 11 of the first air conditioner unit 10 does not exhibit sufficient heating function because the heat of the engine coolant lacks.

When the compressor 1 is operating, the high temperature and high pressure refrigerant discharged from the compressor 1 opens the second open / close valve Vb, the second condenser 21, the liquid tank 4b and the second expansion valve 5b. It flows into the excess heat exchanger 30 through, and the refrigerant from the excess heat exchanger 30 is returned to the compressor (1). Therefore, heat exchange is performed between the air flowing in the air flow passage 20f of the second air conditioner unit 20 and the second condenser 21. After heating the air, the refrigerant having the intermediate temperature and the high pressure is subjected to adiabatic expansion at the second expansion valve 5b to be introduced into the excess heat exchanger 30 as a low temperature low pressure refrigerant. That is, the air flowing in the air flow passage 20f of the second air conditioner unit is heated by the second condenser 21.

Due to the provision of the excess heat exchanger 30, the heating effect of the second condenser 21 is much increased. That is, the low temperature low pressure refrigerant flowing in the excess heat exchanger 30 absorbs heat from the ambient air before it is introduced back into the compressor 1. That is, before being compressed by the compressor 1, the returning refrigerant is warmed to some level which changes the entropy of the refrigerant. Thus, the second condenser 21 can exhibit a higher heating effect. This effect becomes noticeable with increasing time.

Immediate heating to the rear of the vehicle interior is achieved.

As time increases, the temperature of the engine cooling water increases, so that the heating effect of the heater core 11 of the first air conditioning unit 10 gradually increases. Therefore, after a while, the first air conditioning unit 10 supplies the warmed air to the front part of the vehicle interior.

As time increases, the temperature of the engine coolant increases, thereby gradually increasing the heating effect of the excess heat exchanger 30. Therefore, the heating effect of the second condenser 21 increases with the increase of time.

The refrigerant condensed by the second condenser 21 is stored by the liquid tank 4b so that the amount of refrigerant flowing in the refrigerant line of the second air conditioning unit 20 is properly controlled.

(2) cooling operation

The cooling operation is performed only by the first air conditioning unit 10.

In order to start the cooling operation, the third open / close valve Vc is opened to return the refrigerant remaining in the first condenser 3 to the compressor 1. Then, the first opening / closing valve Va is opened and the second and third opening closing valves Vb and Vc are closed. Then, the compressor 1 is operated. At this time, the high temperature and high pressure refrigerant from the compressor 1 is passed through the first opening / closing valve Va, the first condenser 3, the liquid tank 4a and the first expansion valve 5a. ) And the refrigerant from the first heat exchanger 12 is returned to the compressor (1).

Due to this circulation of the refrigerant, the first heat exchanger 12 serving as an evaporator cools the air flowing in the air flow passage 10f to provide cooled air in the front part of the vehicle interior.

The refrigerant condensed by the first condenser 3 is stored by the liquid tank 4a so that the amount of refrigerant flowing in the refrigerant line of the first air conditioning unit 10 is properly controlled.

7-17, in particular with reference to FIG. 7, there is shown an air conditioning system 100D suitable for an electric vehicle, which is a fourth embodiment of the present invention.

As will be apparent from the description, a so-called heat pump type air conditioner is actually used in the fourth embodiment. Further, in the system 100D of the fourth embodiment, under heating operation, the refrigerant supplied directly to the compressor is heated by heating means as in the systems 100A, 100B, 100C of the first, second and third embodiments described above. (Warm up). However, in the fourth embodiment, the heating means is an electric heater.

As shown in FIG. 7, the air conditioning system 100D of the fourth embodiment includes an air conduit case 110 having an intake portion 112, a body portion 114, and an air distribution portion 116. As shown in FIG. As shown, in the air intake 112, an electric blower 118 is introduced to introduce external air and / or internal air into the body portion 114 through the intake door 120. In the main body 114, an evaporator (heat exchanger) 22 and a second condenser 21 are provided. The evaporator 22 is arranged upstream of the second condenser 21. Due to the provision of the second condenser 21, two air passages, a low temperature air passage 114a for bypassing the second condenser 21 and a hot air passage 114b passing through the second condenser 21, It is formed in the main body 114. In the main body 114, the air mixing door 126 is pivotally installed in such a manner as to change the opening degree ratio between the two passages 114a and 114b. Behind the two passages 114a and 114b, an air mixing chamber 114c provided in the air distribution section 116 is formed. The air distribution section 116 has three outflow ports: a defroster port 116a towards the inner surface of the windshield (not shown), a vent port 116b towards the front of the vehicle interior and the vehicle It has a bottom port 116c facing the bottom of the room. Although not shown in the figure, each door is incorporated with these three ports 116a, 166b, 116c to obtain various air conditioning modes.

The evaporator 22 and the second condenser 21 constitute part of a closed refrigeration / heat pump system that circulates the refrigerant under pressure. That is, two selectable systems, the compressor 1, the first condenser 3, the check valve 122, the second condenser 21, the liquid tank 4b, the expansion valve 5b, the evaporator 22. And a closed refrigeration system comprising an accumulator 124, a compressor 1, a check valve 126, a second condenser 21, a liquid tank 4b, an expansion valve 5b, an evaporator 22 and an axle. And a heat pump system including an inflator 124. Due to the use of the accumulator 124, only gaseous refrigerant is introduced into the compressor 1.

In order to switch between the two systems, a four way valve 128 is used which is arranged just downstream of the compressor 1 as shown. The four-way valve 128 has a first outlet towards the inlet of the first condenser 3 for the closed refrigeration system and a second outlet towards the shock valve 126 for the heat pump system. A feedback circuit m is provided which extends from the first outlet of the four-way valve 128 to the inlet of the accumulator 124.

Electric fans 130A and 130B are arranged to cool the first condenser 3.

In the fourth embodiment, there is further provided an excess evaporator 30 arranged in the refrigerant line between the outlet of the evaporator 22 and the inlet of the accumulator 124. The excess evaporator 30 is arranged outside the air conduit case 110, ie in the motor compartment of the associated electric vehicle. The surplus evaporator 30 is equipped with an electric heater 30a powered by a high power battery 132 (eg, DC: 336V) of the electric vehicle. In the excess evaporator 30, a thermally conductive material 30b is provided. Upon operation of the electric heater 30a, the return refrigerant from the evaporator 22 is heated or at least warmed up.

In the following, operation of the air conditioning system 100D of the fourth embodiment will be described.

(1) cooling operation

In order to achieve this operation, the four-way valve 128 is switched to connect the outlet of the four-way valve to the inlet of the first condenser 3. In operation of the compressor 1, the high temperature and high pressure refrigerant from the compressor 1 is introduced into the first and second condensers 3, 21 to be liquefied and then into the expansion valve 5b through the liquid tank 4b. do. Thus, the liquefied refrigerant expands in the evaporator (heat exchanger) 22 to cool the air flowing through the evaporator. Thus, the air conditioning system 100D provides the cooled air in the vehicle interior. Due to the nature of this system, it should be noted that the second condenser 21 generates substantially no heat.

Under this cooling operation, the excess heat exchanger 30 is not heated by the heater 30a.

(2) heating operation

To accomplish this operation, the four way valve 128 is set to connect the outlet of the four way valve with a refrigerant line for the check valve 126. Upon operation of the compressor 1, the high temperature and high pressure refrigerant from the compressor 1 is introduced into the second condenser 21 via the check valve 126, where the refrigerant liquefies while releasing heat. . Thus, the air flowing through the second condenser 21 is warmed up. Then, the liquefied refrigerant is expanded in the expansion valve 5b, and then the refrigerant absorbs heat from the surroundings in the evaporator (heat exchanger) 22. Thus, the air flowing through the evaporator 22 is cooled and dehumidified. That is, the air conditioning system 100D supplies controlled air (more specifically, dehumidified and warmed) to the vehicle interior. By controlling the air mixing door 126, the temperature of the regulated air is changed.

During this heating operation, the excess evaporator 30 remains heated to heat or at least warm the return refrigerant. Thus, as described above, the heating effect of the second condenser 21 is increased. Moreover, due to the thermally conductive material 30b installed in the surplus evaporator 30, the heating effect of the second condenser 21 is further enhanced.

Preferably, the valve opening of the expansion valve 5b is controlled by the temperature of the refrigerant discharged directly from the excess evaporator 30. By using this method, the amount of refrigerant supplied to the evaporators 22, 30 can be controlled to cause the refrigerant introduced directly into the compressor 1 to take the appropriate overheating conditions.

As described above, under the heating operation, in the excess evaporator 30, the return refrigerant is heated or at least warmed by the electric heater 30a while being evaporated. Thus, the refrigerant discharged from the compressor 1 has a much higher temperature, so that the second condenser 21 exhibits a much higher heating effect. That is, the vehicle interior can be warmed up immediately.

Moreover, if the valve opening of the expansion valve 5b is controlled by the temperature of the refrigerant discharged directly from the excess evaporator 30, the amount of refrigerant flowing in the heat pump system is determined by the excess evaporator 30 by the heater 30a. Increased when heated. This enhances the heating effect of the second condenser 21.

Moreover, due to the heating of the return refrigerant by the electric heater 30a, the refrigerant introduced into the compressor 1 can have a complete gas state, which improves the durability of the compressor 1.

As mentioned above, the excess evaporator 30 is arranged in an open area of the electric vehicle, for example in the motor compartment of the electric vehicle.

8-11, the redundant evaporator 30 used in the system 100D of the fourth embodiment is clearly shown.

As best seen in FIG. 8, the excess evaporator 30 includes an elongated case 50 equipped with a lid 52 to form a sealing chamber 54 therein. In the chamber 54, a spiral sheath heater 56 and a straight refrigerant flow tube 58 are provided. The heater 56 and the tube 58 are arranged in the longitudinal direction in the long case 50. The refrigerant flow tube 58 is coaxially surrounded by the spiral sheath heater 56. Sealing chamber 54 is filled with liquid coolant 60. The coolant flow tube 58 has respective connector pipes 58a and 58b exposed at both ends of the case 50. The pipe 58a is connected to the outlet port of the evaporator 22 and the other pipe 58b is connected to the inlet port of the accumulator 124.

Spiral sheath heater 56 is shown clearly in FIG. 11, which includes nichrome contained within a spiral metal sheath. The metal sheath includes the heat resistant insulation material therein. As can be seen from Figs. 8 and 11, the sheath heater 56 has respective terminal ends 56a and 56b exposed at the outside of the case 50 at both ends. The terminal end 56a is connected to one polarity of the battery mounted in the vehicle, and the other terminal end 56b is connected to the electric control device.

As understood from FIGS. 8 and 10, the lid 52 is equipped with an inlet opening 52a for pouring the liquid coolant 60 into the case 50. The inlet opening 52a is equipped with a safety valve 62 which automatically opens when the temperature of the liquid coolant 60 is abnormally increased. The temperature sensor 140 is installed in the case 50 to detect the temperature of the liquid coolant 60. As will be described later, the operation of the sheath heater 56 is controlled by a temperature sensor.

Due to the use of liquid coolant 60 with significant heat capacity, the refrigerant flow tube 58 is not directly affected by the on / off operation of the electric heater 56. As a result, stable heating is obtained from the air conditioning system 100D.

As described above, the heater 56 and the tube 58 are arranged in the longitudinal direction in the long case 50. By such an arrangement, preferred free convection of the liquid coolant 60 is likely to occur. That is, this convection enhances the phenomenon that the coolant 60 has an equalized temperature throughout. This equalization stably applies heat to the return refrigerant, so that a stable heating effect is achieved by the second condenser 21. Moreover, undesirable hunting of the heat pump system is suppressed.

If desired, suitable agitation means, such as an electric fan, may be provided to agitate the liquid coolant 60 in the case 50.

12-14 show redundant evaporator 300A incorporating such agitation means.

As can be seen from FIG. 12, the surplus evaporator 300A is formed of a vessel 302 filled with a liquid coolant 60 and a spiral provided in the vessel 302, as in the case of the surplus evaporator 30 described above in FIG. A sheath heater 56 and a straight refrigerant flow tube 58 surrounded by the spiral heater 56 are included. Spiral fins 58c are disposed on the coolant flow tube 58 to increase the contact area with the liquid coolant 60. That is, the fin 58c improves heat transfer from the liquid coolant 60 to the tube 58. Moreover, the spiral shape of the fins 58c enhances convection that may be caused by the liquid coolant 60. That is, the liquid coolant 60 flows around the refrigerant flow tube 58 using the fins 58a as guides. If desired, flow tube 58 may be provided with fins therein.

As can be seen from FIG. 12, the container 302 has an inlet opening 302a and an outlet opening 302b connected to the tube 304. The electric pump 306 is disposed in the tube 304. Thus, upon operation of the pump 306, the liquid coolant 60 is propelled in the direction indicated by the arrow in the tube 304, thereby stirring the coolant 60 in the vessel 302.

As understood from FIGS. 14 and 15, the liquid coolant 60 introduced from the inlet opening 302a into the interior of the vessel 302 will flow toward one end portion of the fin 58c and then the outlet opening. The fin 58c is used as a guide to flow around the refrigerant flow tube 58 toward the other end portion of the fin 58c where the 302b is located. In order to achieve this flow effectively, it is desirable to separate the fins 58c by about 3 to 4 mm from the helical sheath heater 56.

Fig. 16 shows the case where the excess evaporator 300A is arranged vertically with the refrigerant flow tube 58 extending vertically. Even in this case, the stirring required for the coolant 60 is obtained.

Referring to Fig. 17, a block diagram of a control circuit employed in the air conditioning system 100D is shown.

As shown, the compressor 1, more specifically the electric motor of the compressor 1, is connected to one terminal of a power source (ie, a high power battery) 132 via an inverter 132. The other terminal of the battery 132 is grounded, ie connected to the chassis of the electric vehicle. The terminal end 56a of the sheath heater 56 of the redundant evaporator 30 is connected to one terminal of the battery 132, and the other terminal end of the heater 56 is one terminal 136a of the relay 136. Is connected to. The other terminal 136b of the relay 136 is connected to the chassis of the vehicle. The two terminals 136a and 136b are connectable by armature 136c. To drive the armature 136c, the relay 136 has a coil 136d, one terminal of which is connected to the chassis, and the other terminal of the coil, to the control unit 138. Thus, the operation of the sheath heater 56 is controlled in an on / off manner by the control unit 138. The control unit 138 is of a microcomputer configured to control the air conditioning system 100D in an integrated manner. The control unit 138 is driven by the power from the inverter 134. The information signals from the various sensors are processed by the control unit 138 which controls the various devices. The sensors pass, for example, directly through the evaporator 22 in the temperature sensor 140 for the liquid coolant 60 in the surplus evaporator 30 and the temperature of the outside and internal air, solar radiation, and the air conduit case 110. There are other known sensors 142 that sense the temperature of one air. Information signals from various manual operation switches 144 on the control panel are also supplied to the control unit 138. Moreover, information signals from the position sensor 146 for the various damper doors of the air conduit case 110 are supplied to the control unit 138. When processing the information signal applied to the control unit, the control unit 138 is the various display devices of the control panel, the position of the damper door of the air conduit case 110, and the various electric fans 148 arranged in the air conditioner. To control. As shown, several actuators 146a are provided for controlling the position of the damper door, and several actuating circuits 148a are provided for controlling the electric fan 148.

In the air conditioning system 100D, the control unit 138 turns on the relay 136 when the temperature of the return refrigerant directly entering the compressor 1 under the heating operation is lower than the set level so that the surplus evaporator 30 can be used. Arranged to cause heater 56 to actuate. More specifically, the control unit 138 controls the heater 56 in accordance with the information signal from the temperature sensor 140 of the surplus evaporator 30.

18 is a chart showing the on / off operation of the spiral sheath heater 56 in accordance with the temperature of the return refrigerant. As can be understood from the chart, the operation is stopped when the temperature of the returning refrigerant is heated to 70 ° C due to the operation of the heater 56, and the heater 56 is operated when the temperature of the returning coolant drops to 60 ° C.

In an improved automotive dual air conditioning system incorporating the principle of dual functional in accordance with the present invention, the first air conditioning unit is configured to provide external air (i.e. vehicle exterior air) and / or internal air (i.e. vehicle interior air). ) Is selectively taken to regulate the air before discharging the air to the front of the vehicle cabin, while the second air conditioning unit takes the internal air and regulates the air before discharging the air to the rear of the vehicle interior. Under heating operation of the air conditioning system, isotropic compression is effectively performed by the compressor due to the returning refrigerant being warmed. That is, effective heating is achieved by the air conditioning system. In the cooling operation, three modes are available by controlling the first open / close valve and the second open / close valve, namely the front cooling mode, the double cooling mode and the rear cooling mode.

Claims (30)

In a vehicle air conditioning system, A first refrigerant circulation comprising a compressor, a first condenser, a second condenser, a liquid tank, an expansion valve, and an evaporator, connected to one another via a pipe, wherein the refrigerant flows from the outlet of the compressor to the inlet of the compressor while changing phases. A first cycle which forms a circuit and causes the evaporator to act as a cooler in operation; A second refrigerant comprising the compressor, the second condenser, the liquid tank, the expansion valve and the evaporator, connected to one another via a pipe, the refrigerant flowing from the outlet of the compressor to the inlet of the compressor while changing phase Forming a circulation circuit, wherein in operation a second cycle causing said condenser to act as a heater and said evaporator to act as a cooler Switch means for switching between the first cycle and the second cycle; An air conduit case provided with the second condenser and the evaporator and having an air flow passage connected to a vehicle interior of the vehicle at a downstream side thereof; And heater means for heating a return refrigerant flowing in a pipe extending from an outlet of said evaporator to an inlet of said compressor under operation of said second cycle. The heat exchanger of claim 1, wherein the heater means comprises a heat exchanger having hot water generating means for generating hot water, a first passage through which the return refrigerant flows, and a second passage through which the hot water flows, The passageway and the second passageway are arranged to exchange heat between the first passageway and the second passageway. 3. The air conditioning system for a vehicle according to claim 2, wherein said hot water generating means is a water jacket of an internal combustion engine mounted to said vehicle. The air conditioning system for a vehicle according to claim 2, wherein the heat exchanger has a plurality of heat dissipation fins. 2. The heater of claim 1 wherein the heater means comprises another evaporator having an inlet connected to the outlet of the evaporator and an outlet connected to the inlet of the compressor via an accumulator, and an electric heater that heats the refrigerant flowing in the other evaporator. Vehicle air conditioning system, characterized in that. The air conditioning system of claim 1, wherein the heater means is disposed at a position other than an air flow passage of the air conduit case. The vehicle air conditioning system according to claim 1, wherein the air conduit case is equipped with an electric blower for introducing external air and / or internal air of the vehicle into the air flow passage of the air conduit case. 8. The air conditioning system of claim 7, wherein the evaporator is disposed upstream of the second condenser with respect to the direction in which air in the air flow passage is caused to flow by the electric blower. In a dual air conditioning system for an automobile powered by an internal combustion engine, Inlet of the compressor from the outlet of the compressor, with the refrigerant changing phase, including a compressor, a first condenser, a first liquid tank, a first expansion valve, and a first heat exchanger, driven by the internal combustion engine, connected to each other via a pipe. A first cycle to form a first refrigeration circuit that flows into the refrigerant and the refrigerant including the compressor, the liquid tank, the second condenser, the second liquid tank, the second expansion valve and the second heat exchanger connected to each other via a pipe. A second cycle for forming a second refrigeration circuit which flows from the outlet of the compressor to the inlet of the compressor while changing the virtual phase, and first switch means for switching the first cycle and the second cycle, A first system for actuating the first heat exchanger and the second heat exchanger as a cooler in operation; A third cycle including the same parts as the first cycle except for the first condenser, a fourth cycle including the same parts as the second cycle except the first condenser, and the third cycle And a second switch means for switching a fourth cycle, said second system for acting as said cooler and said second condenser as a heater; A heater core into which hot water from the water jacket of the internal combustion engine is introduced; An air conduit case including a first air flow passage in which the heater core and the first heat exchanger are installed, and a second air flow passage in which the second condenser and the second heat exchanger are installed; Heater means for heating a return refrigerant to enter the inlet of the compressor under operation of the second system, And the first air flow passage and the second air flow passage each connected to a vehicle interior of the vehicle in a downstream portion. 10. The dual air conditioning system according to claim 9, wherein the heater means is disposed at a position other than the first air flow passage and the second air flow passage. 10. The apparatus of claim 9, wherein the first switch means for the first system comprises: a first mode in which only the first cycle is operated; a second mode in which both the first and second cycles are operated; Providing a third mode in which only two cycles are operated, the second switch means for the second system having a fourth mode in which only the fourth cycle is in operation, and both the third and fourth cycles in operation And a fifth mode. 11. The dual air conditioning system according to claim 10, wherein the heater means uses hot water from a water jacket of the internal combustion engine to heat the return refrigerant. The heat exchanger according to claim 12, wherein the heater means is a heat exchanger including a first passage through which the returned refrigerant flows and a second passage through which hot water from the water jacket flows, wherein the first flow passage and the second flow passage And the heat exchange between the first flow passage and the second flow passage. 15. The compressor of claim 13, wherein the dual air conditioning system also includes bypass means for bypassing a heat exchanger that is the heater means, wherein the bypass means includes an inlet of the compressor when the temperature of the return refrigerant is heated to a predetermined level. And an inlet of the heat exchanger directly. 15. The dual air conditioning system according to claim 14, wherein said bypass means is equipped with a control valve. The dual air conditioning system according to claim 13, wherein the heat exchanger is provided with a plurality of heat dissipation fins. 10. The dual air conditioning system as claimed in claim 9, further comprising a temperature sensor for sensing the temperature of the return refrigerant discharged directly from the heating means to control the valve opening of the second expansion valve. 18. The dual air conditioning system according to claim 17, wherein the temperature sensor is disposed on a refrigerant outlet pipe extending from said heating means. 18. The dual air conditioning system according to claim 17, wherein the controller increases the valve opening of the second expansion valve when the temperature sensor detects that the temperature of the refrigerant immediately discharged from the heating means is relatively high. In a dual air conditioning system for an automobile powered by an internal combustion engine, A compressor, a first condenser, a first liquid tank, a first expansion valve, and a first heat exchanger, driven by the internal combustion engine, connected to each other via a pipe, allowing refrigerant to flow from the outlet of the compressor to the inlet of the compressor. A first cycle for forming a first refrigerant circulation circuit, wherein the first heat exchanger acts as a cooler during operation; A second refrigerant circulation circuit comprising the compressor, a second condenser, a second liquid tank, and a second expansion valve connected to each other via a pipe, the refrigerant flowing from an outlet of the compressor to an inlet of the compressor, A second cycle in which said second condenser acts as a heater, Switch means for switching between the first cycle and the second cycle; A heater core into which hot water from the water jacket of the internal combustion engine is introduced; An air conduit having a first air flow passage in which the heater core and the first heat exchanger are installed, and a second air flow passage in which the second condenser is installed; Heater means for heating a returning refrigerant to enter the inlet of said compressor under operation of said second cycle, Wherein each of said first air flow passage and said second air flow passage is connected to a vehicle interior of the vehicle in a downstream portion. 21. The method of claim 20, further comprising a connecting pipe, one end of which is connected to the inlet of the compressor and the other end of which is connected to the outlet of the first condenser, and an open / close valve operably disposed on the connecting pipe. Dual air conditioning system. 22. The dual air conditioning system according to claim 21, wherein said second liquid tank, said second expansion valve and said heater means are located at positions other than said first air flow passage and second air flow passage. In the air conditioning system for an electric vehicle, A compressor, a first condenser, a second condenser, a liquid tank, an expansion valve, and an evaporator, driven by an electric motor, connected to each other via a pipe, the refrigerant flowing from the outlet of the compressor to the inlet of the compressor with phase change Forming a first refrigerant circulation circuit, the first cycle of causing the evaporator to act as a cooler in operation; A second, comprising said compressor, said second heat exchanger, said liquid tank, said expansion valve and said evaporator, connected to one another via a pipe, wherein a refrigerant flows from the outlet of said compressor to the inlet of said compressor while changing phases; Forming a refrigerant circulation circuit, wherein in operation a second cycle causing said condenser to act as a heater and said evaporator to act as a cooler; Switch means for switching between the first cycle and the second cycle; An air conduit case provided with the second condenser and the evaporator and having an air flow passage connected to a vehicle interior of the electric vehicle at a downstream side thereof; Heater means for heating a return refrigerant flowing in a pipe extending from an outlet of an evaporator to an inlet of said compressor under operation of said second cycle. 24. The apparatus of claim 23, wherein the heater means comprises a vessel filled with a liquid coolant, a refrigerant flow tube having one end connected to an outlet of the evaporator and the other end connected to the inlet of the compressor, and a liquid coolant installed in the vessel. And an electric heater installed in the vessel to heat the refrigerant flowing in the tube by heating. 25. The air conditioning system of claim 24, wherein the electric heater is a spiral sheathed heater arranged to surround the straight refrigerant flow tube. 27. The air conditioning system according to claim 25, further comprising stirring means for stirring a liquid coolant in the vessel. 27. The apparatus of claim 26, wherein the stirring means comprises a coolant flow tube having one end connected to a portion of the interior of the vessel and the other end connected to another portion of the interior, and an electric pump disposed within the coolant flow tube. Air conditioning systems for electric vehicles. 28. The air conditioning system of claim 27, wherein the coolant flow tube is formed with a helical fin disposed coaxially on the coolant flow tube. 27. The air conditioning system of claim 26, further comprising a temperature sensor installed inside the vessel to sense the temperature of the liquid coolant. 30. The air conditioning system according to claim 29, further comprising a safety valve connected to the container and automatically opening when the temperature of the liquid coolant increases abnormally.