JP2003285633A - Air conditioning apparatus for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To keep the heat exchanging performance of an evaporator excellent in a radiation cooling mode following a stop of a compressor as well as in operation of the compressor. <P>SOLUTION: The air conditioning apparatus for a vehicle is provided with a compressor 1 driven by a vehicle engine 4, which is automatically stopped during a stop of the vehicle, an evaporator 8 for cooling ventilation air toward a cabin, a heat regenerator 11 having a cold reserving material 11a cooled by low pressure refrigerant during the operation of the compressor, and an electric pump 14 for circulating the refrigerant between the evaporator 8 and the heat regenerator 11 during a stop of the compressor. When the compressor is stopped, the gaseous refrigerant evaporated in the evaporator 8 is condensed with the cold stored in the cold reserving material 11a. The liquid refrigerant is introduced into the evaporator 8. The direction of the flow of the refrigerant during the stop of the compressor is the same as that of the flow of the refrigerant during the operation of the compressor. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold storage type air conditioner for a vehicle which is applied to a vehicle in which a vehicle engine, which is a drive source of a compressor, is temporarily stopped when the vehicle is stopped.

[0002]

2. Description of the Related Art In recent years, a vehicle (eco-run vehicle such as a hybrid vehicle) in which a vehicle engine is automatically stopped when a vehicle is stopped such as waiting for a signal has been put into practical use for the purpose of environmental protection and improvement of fuel consumption of the vehicle engine. , In the future, the number of vehicles that stop the vehicle engine when the vehicle is stopped tends to increase.

By the way, in the vehicle air conditioner, the compressor of the refrigeration cycle is driven by the vehicle engine. Therefore, in the above eco-run vehicle, the vehicle is stopped by waiting for a signal or the like and is compressed every time the vehicle engine is stopped. The air conditioner also stops, the temperature of the cooling evaporator rises, and the temperature of the air blown into the passenger compartment rises, which impairs the cooling feeling of the passengers.

Therefore, the vehicle engine (compressor) is provided with a cool storage means for storing cold when the vehicle engine (compressor) is operating.
There is a growing need for a regenerative vehicle air conditioner that can cool the air blown into the vehicle compartment by using the amount of stored heat of the regenerator when the cooling action of the evaporator is stopped.

As a cold storage type vehicle air conditioner of this type,
Conventionally, the one described in Japanese Patent Laid-Open No. 2000-313226 is known. In this conventional technique, in a refrigeration cycle for air conditioning R having a compressor 1 driven by a vehicle engine as shown in FIG. 13, a cool storage material 40a is built in parallel with an evaporator 8 for cooling blown air into the vehicle interior. A cold storage heat exchanger 40 is provided.

When cold storage is performed when the vehicle engine (compressor 1) is in operation, the solenoid valve 41 is opened, and the low-pressure refrigerant decompressed by the expansion valve 6 is cooled by the evaporator 8 and the cold storage heat exchanger 40.
In parallel to cool the regenerator material 40a to cool the regenerator material 40a.

When the compressor 1 is stopped due to the stop of the vehicle engine, the electric pump 42 is operated, and the liquid storage tank 43 → the solenoid valve 41 → the electric pump 42 → the cold storage heat exchanger 40 → the evaporator 8 → the liquid storage. The refrigerant is circulated in the closed circuit of the tank 43. The vapor-phase refrigerant evaporated in the evaporator 8 is condensed in the cold storage heat exchanger 40 by the amount of cold storage heat of the cold storage material 40a,
The condensed liquid refrigerant is circulated to the evaporator 8. As a result, the cooling action of the evaporator 8 is continued even when the compressor 1 is stopped so that the cooling function of the vehicle interior can be exhibited.

[0008]

As described above, in the prior art, when the compressor 1 is in operation, the direction from the expansion valve 7 through the liquid storage tank 43 and the evaporator 8 toward the suction side of the compressor 1. Refrigerant flows into. On the contrary, when the compressor 1 is stopped (during cooling and cooling), the direction from the suction side of the compressor 1 to the liquid storage tank 43 side through the evaporator 8, that is, the direction opposite to the operation direction of the compressor. Refrigerant flows into.

In this way, the refrigerant flow direction of the evaporator 8 is reversed when the compressor 1 is operating and when it is stopped, so that the heat exchange performance of the evaporator 8 varies. Therefore, the evaporator heat exchange performance cannot be maintained in a high state both when the compressor 1 is operating and when the compressor is stopped.

This inconvenience will be described with reference to the concrete refrigerant flow path structure of the evaporator 8 shown in FIG. FIG. 14 shows a specific example of the refrigerant channel structure of the evaporator 8, which is the refrigerant channel structure described in JP-A-9-170850.
The one described in this publication is intended to improve the heat exchange efficiency of the evaporator 8 by a refrigerant flow path configuration in which a cross flow and a counter flow are combined.

That is, in FIG. 14, the evaporator 8 has a refrigerant inlet side heat exchange section 81 arranged on the lee side in the air flow direction A, and a refrigerant outlet side heat exchange section 82 on the windward side in the air flow direction A.
Are arranged. Then, in the refrigerant inlet side heat exchange section 81, the refrigerant inlet 84 is arranged on one (right) side surface portion 83a of the left and right side surfaces of the evaporator 8, and the refrigerant is fed from the refrigerant inlet 84 in the direction of the arrow B1. Lower tank part 85
Flows into the right side space 85a. Here, the inner space of the lower tank portion 85 is partitioned by a partition plate 86 into a right space 85a and a left space 85b.

The refrigerant is the right space 85a of the lower tank portion 85.
From the upper side to the upper tank portion 87 by ascending in the right side refrigerant flow passage 81 a of the refrigerant inlet side heat exchange portion 81. This upper tank part 87
Since there is no partition plate inside, the upper tank 8
The refrigerant flows to the left in 7 as indicated by arrow B2.

Next, the refrigerant descends through the left side refrigerant flow passage 81b of the refrigerant inlet side heat exchange section 81 to reach the left side space 85b of the lower tank section 85, and the left side space 85b is directed to the left side as indicated by arrow B3. Flows.

Of the left and right side surfaces of the evaporator 8, a side surface refrigerant passage 88 is formed in the other (left side) side surface portion 83b, and the left side end portion of the lower tank portion 85 has this side surface refrigerant flow. It communicates with the lower end of the passage 88. Since the upper end portion of the side surface refrigerant passage 88 communicates with the left side space 89a of the upper tank portion 89 of the refrigerant outlet side heat exchange portion 82, the refrigerant passes through the side surface refrigerant passage 88 and the left side space 89a. And flows to the right through the left space 89a as indicated by arrow B4.

Here, the inner space of the upper tank portion 89 is partitioned by a partition plate 90 into a left space 89a and a right space 89b. Therefore, the refrigerant in the left space 89a of the upper tank portion 89 next descends in the left refrigerant passage 82a of the refrigerant outlet side heat exchange portion 82 and reaches the lower tank portion 91.

Since no partition plate is provided in the lower tank portion 91, the refrigerant flows rightward in the lower tank portion 91 as indicated by arrow B5. From the right side area of the lower tank section 91, the refrigerant rises in the right side refrigerant flow path 82b of the refrigerant outlet side heat exchange section 82 and reaches the right side space 89b of the upper tank section 89. Since the right side space 89b is communicated with the refrigerant outlet 92 arranged on one side surface (right side) 83a of the evaporator 8, the refrigerant in the right side space 89b flows out of the evaporator 8 through the refrigerant outlet 92.

The respective refrigerant flow paths 81a, 81b, 82
Although a and 82b are shown schematically, in reality, each is composed of a plurality of tubes arranged in parallel. As is well known, this tube has a laminated structure of thin metal plates such as aluminum.

In the evaporator refrigerant flow passage configuration of FIG. 14, air is orthogonal to the refrigerant flow direction in the refrigerant inlet side heat exchange section 81 and the refrigerant outlet side heat exchange section 82 (the lateral direction of the evaporator 8). And has a cross-flow refrigerant flow path configuration. Then, the refrigerant inlet side heat exchange section 81 is arranged on the leeward side in the air flow direction A, and the refrigerant outlet side heat exchange section 82 is arranged on the windward side in the air flow direction A, thereby forming a counterflow refrigerant flow path configuration. Has become.

The pressure reducing device arranged on the upstream side of the evaporator is usually constituted by a temperature type expansion valve 7 (FIG. 13) so that the refrigerant at the outlet of the evaporator has a predetermined superheat degree. The cycle circulation refrigerant flow rate is adjusted. Therefore, in the evaporator 8, a refrigerant superheat region is formed in the refrigerant outlet side region thereof, and the outlet side refrigerant temperature of the evaporator 8 becomes higher than the inlet side refrigerant temperature.

Therefore, by constructing the counter-flow refrigerant passage in the air flow direction A as described above, the air and the refrigerant are exchanged in both the refrigerant inlet side heat exchange section 81 and the refrigerant outlet side heat exchange section 82. It is possible to improve the heat exchange performance of the evaporator 8 by increasing the temperature difference.

Further, in the refrigerant flow path configuration of the evaporator 8, the evaporation of the refrigerant gradually progresses from the refrigerant inlet side to the refrigerant outlet side, and the ratio (dryness) of the vapor phase refrigerant increases, so that the refrigerant outlet side. The increase in pressure loss due to the increase in the flow velocity of the refrigerant becomes remarkable in the flow passage. Therefore, in order to reduce this increase in pressure loss, the refrigerant flow paths 81a and 81b of the refrigerant inlet side heat exchange section 81 are reduced.
The refrigerant flow path 82a of the refrigerant outlet side heat exchange section 82,
It is designed to increase the flow passage cross-sectional area of 82b.

Therefore, if the refrigerant is set to flow in the evaporator 8 in the refrigerant flow direction shown in FIG. 14 when the compressor is operating (normal cooling / storage), in the prior art shown in FIG. 13, when the compressor is stopped (cooling and cooling). Since the refrigerant flows to the evaporator 8 in the opposite direction, the inlet-side refrigerant flow path is located on the windward side of the air flow,
The outlet side refrigerant flow path is located on the leeward side of the air flow, and a parallel flow state is established. Therefore, the temperature difference between the air and the refrigerant in the outlet-side refrigerant flow channel is significantly reduced, and the heat exchange performance is significantly reduced.

Further, when the compressor is stopped (during cooling and cooling), the refrigerant flow passage having a large flow passage cross-sectional area is on the refrigerant inlet side, and the refrigerant flow passage having a small flow passage cross-sectional area is on the refrigerant outlet side. The pressure loss of the evaporator 8 is significantly increased as compared to when the compressor is in operation, and as a result, the refrigerant circulation flow rate to the evaporator 8 is reduced and the heat exchange performance is further reduced.

That is, according to the conventional technique shown in FIG. 13, the direction of the refrigerant flow to the evaporator 8 when the compressor is stopped is opposite to that when the compressor is operating, so that the original heat exchange of the evaporator 8 is performed when the compressor is stopped. The performance cannot be exhibited, and the cooling and cooling performance is significantly reduced.

In view of the above points, the present invention can exhibit the heat exchange performance of the evaporator in the cold storage cooling air-conditioning mode accompanying the stop of the compressor in the same manner as when the compressor is operating, in the cold storage type air conditioner for a vehicle. The purpose is to do so.

[0026]

In order to achieve the above object, the invention as set forth in claim 1 is a vehicle air conditioner mounted on a vehicle for controlling to stop the vehicle engine (4) at least when the vehicle is stopped. The compressor (1) driven by the vehicle engine (4), the high pressure side heat exchanger (6) for radiating the high pressure refrigerant discharged from the compressor (1), and the high pressure side heat exchanger (6). ), A pressure reducing means (7, 70) for reducing the pressure of the refrigerant passing therethrough, and an evaporator (8) for evaporating the low pressure refrigerant reduced by the pressure reducing means (7, 70) to cool the air blown into the vehicle interior. A cold storage heat exchanger (11) having a cold storage material (11a) that is cooled by a low-pressure refrigerant when the compressor (1) is in operation, and when the vehicle engine (4) is stopped and the compressor (1) is stopped. , A refrigerant between the evaporator (8) and the cold storage heat exchanger (11) When the compressor (1) is stopped, the gas-phase refrigerant evaporated in the evaporator (8) is cooled and condensed by the cold storage heat of the cold storage material (11a), and condensed after the condensation. The liquid refrigerant is introduced into the evaporator (8), and the evaporator (8) when the compressor (1) is stopped
The refrigerant flow direction to the evaporator (8) is the same as the refrigerant flow direction to the evaporator (8) when the compressor (1) is in operation.

As a result, in the cold storage type vehicle air conditioner, the refrigerant flow to the evaporator (8) is in the same direction when the compressor is stopped and when the compressor is operating, so that the cooling and cooling is performed when the compressor is stopped. As in the invention according to claim 2, which can exhibit the evaporator heat exchange performance at the same time as when the compressor is in operation, in claim 1, the cold storage heat exchanger (11) is connected to the compressor (1) to operate. The evaporator (8) may be connected in parallel to the refrigerant flow at any time.

Further, as in the invention described in claim 3, in claim 1, the cold storage heat exchanger (11) is replaced by a compressor (1).
The evaporator (8) may be connected in series with respect to the flow of the refrigerant during the operation.

According to this, when the compressor (1) is in operation, the refrigerant is constantly caused to flow through the series flow path of the cold storage heat exchanger (11) and the evaporator (8) by the operation of the compressor (1), and the evaporator (8) Demonstrate the cooling capacity and cool storage heat exchanger (1
It is possible to store cold in the cold storage material (11a) of 1).

Therefore, in the cold storage type air conditioner for a vehicle, the cooling function and the cold storage function can be satisfactorily exerted with a simple flow path configuration without requiring the opening / closing function of the refrigerant flow path by the valve means.

According to a fourth aspect of the present invention, in the third aspect, the pressure reducing means is an expansion valve (7) for adjusting the refrigerant flow rate according to the degree of superheat of the outlet refrigerant of the evaporator (8). It is characterized in that the exchanger (11) is provided on the refrigerant inlet side of the evaporator (8).

By the way, when the cold storage of the cold storage material (11a) is completed in the cold storage heat exchanger (11), the low-pressure refrigerant passes through the cold storage heat exchanger (11) with almost no heat absorption. Cold storage heat exchanger (11)
When the refrigerant is provided on the refrigerant outlet side of the evaporator (8), the evaporator outlet refrigerant is cooled by the regenerator material (11a) that has completed cold storage, and the expansion valve (7) cannot properly control the refrigerant flow rate. Occurs.

However, according to claim 4, since the cold storage heat exchanger (11) is provided on the refrigerant inlet side of the evaporator (8), the expansion valve (7) is provided with the cold storage heat exchanger (11). The refrigerant flow rate can be appropriately adjusted according to the superheat degree of the refrigerant at the outlet of the evaporator as in the normal cycle.

According to a fifth aspect of the present invention, in the first aspect, an accumulator tank (120) arranged on the refrigerant outlet side of the evaporator (8) is provided, and the evaporator () is provided inside the accumulator tank (120). 8) The gas-liquid of the low-pressure refrigerant at the outlet is separated, and the gas-phase refrigerant is led to the suction side of the compressor (1). The cold storage heat exchanger (11) is used as the refrigerant of the evaporator (8). Outlet side and accumulator tank (120)
And a low-pressure refrigerant that has passed through the cold storage heat exchanger (11) during operation of the compressor (1) passes through the inside of the accumulator tank (120) and is sucked into the compressor (1). The liquid refrigerant in the accumulator tank (120) is introduced into the evaporator (8) by the pump means (14) when the machine (1) is stopped.

Claim 5 relates to an accumulator in which an accumulator tank (120) is arranged on the evaporator outlet side, whereby a compressor (1) can be used without using an expansion valve (7) as a pressure reducing means. Liquid refrigerant return to,
As a result, liquid compression can be prevented. When the expansion valve (7) is not used as the pressure reducing means in this way, the cold storage heat exchanger (1
Even if (1) is provided on the refrigerant outlet side of the evaporator (8), it does not hinder the refrigerant flow rate adjusting action of the cycle.

Further, since the low-pressure refrigerant passing through the cold storage heat exchanger (11) passes through the inside of the accumulator tank (120) and is sucked into the compressor (1), the cold storage heat exchanger (1)
Even if the low-pressure refrigerant is liquefied by the cooling action in 1), the liquid refrigerant can be stored in the accumulator tank (120). Therefore, the accumulator tank (120) can also serve as the liquid refrigerant storage function for the cold storage heat exchanger (11).

Since the low pressure refrigerant temperature on the refrigerant outlet side of the evaporator (8) is lower than that on the refrigerant inlet side by the pressure loss in the refrigerant flow path of the evaporator (8), the evaporator outlet side is reduced. By providing the cold storage heat exchanger (11) in the above, the temperature difference between the low-pressure refrigerant temperature and the cold storage material (11a) increases, and the cold storage material (11a) can be efficiently cooled.

According to the sixth aspect of the present invention, in the fifth aspect, the pressure reducing means (70) can be specifically constituted by a fixed throttle or a variable throttle that responds to a high pressure refrigerant state.

In the invention according to claim 7, in any one of claims 1 to 6, when the compressor (1) is in operation, the low-pressure refrigerant bypasses the pump means (14) and the cold storage heat exchanger ( It is characterized in that it is adapted to flow to 11).

As a result, the problem that the flow rate of the refrigerant is reduced due to the presence of the pump means (14) itself when the compressor is operating does not occur.

The reference numerals in parentheses of the above-mentioned means indicate the correspondence with the concrete means described in the embodiments described later.

[0042]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows a refrigeration cycle R of a vehicle air conditioner according to a first embodiment. A refrigeration cycle R of a vehicle air conditioner has a compressor 1 that sucks, compresses, and discharges a refrigerant, and the compressor 1 is provided with an electromagnetic clutch 2 for connecting and disconnecting power. Since the power of the vehicle engine 4 is transmitted to the compressor 1 via the electromagnetic clutch 2 and the belt 3, the operation of the compressor 1 is interrupted by interrupting the power supply to the electromagnetic clutch 2 by the air conditioning controller 5. It

The high-temperature, high-pressure superheated gas-phase refrigerant discharged from the compressor 1 flows into a condenser 6 which constitutes a high-pressure side heat exchanger, and is cooled by heat exchange with the outside air blown from a cooling fan (not shown) and condensed. To do. The condenser 6 includes a condenser section 6a and a condenser section 6a.
The liquid receiver 6b for separating the gas-liquid of the refrigerant after passing through the liquid refrigerant to collect the liquid refrigerant and for discharging the liquid refrigerant, and the supercooling unit 6c for supercooling the liquid refrigerant from the liquid receiver 6b are integrally configured. It is well known.

The supercooled liquid refrigerant from the supercooling section 6c is depressurized to a low pressure by the expansion valve 7 which constitutes a depressurizing means, and becomes a low pressure gas-liquid two-phase state. The expansion valve 7 is a thermal expansion valve that adjusts the opening degree (refrigerant flow rate) of the valve 7a so as to adjust the degree of superheat of the outlet refrigerant of the evaporator 8 that constitutes the heat exchanger for cooling. In particular,
In this example, the evaporator outlet refrigerant flow path 7b through which the outlet refrigerant of the evaporator 8 flows is configured in the box-shaped housing 7c,
The thermal expansion valve 7 of the type in which the temperature-sensing mechanism for the outlet refrigerant of the evaporator 8 is integrally formed in the housing 7c is used.

The cool storage unit 9 integrally comprises the devices within the chain double-dashed line frame in FIG. 1 as one assembly unit, and the flow path is the outlet flow path of the valve 7a of the thermal expansion valve 7. It is connected to the cold storage heat exchanger 11 via the switching valve 10.
This cold storage heat exchanger 11 is configured by arranging a large number of cold storage material containers 11a enclosing a cold storage material inside a tank member 11b.

More specifically, a large number of regenerator material containers 11a.
Are arranged in the tank member 11b in such a manner that a space for the refrigerant to flow between the containers is formed. Here, the form of the regenerator material container 11a is specifically a stick type having a cylindrical shape elongated in the refrigerant flow direction shown in FIG. 2 (a), a ball type shown in FIG. 2 (b), and FIG. ) Any of the capsule types shown in FIG. Cool storage material container 11a
Can be formed of a resin-made thin film pack member or a metal plate material such as aluminum.

The cold storage material sealed in the cold storage material container 11a is cooled by a low-pressure refrigerant and undergoes a phase change (liquid phase → solid phase).
Then, a material capable of storing latent heat of solidification is selected, that is, a material that solidifies at a temperature higher than the low-pressure refrigerant temperature is selected.

Here, the low pressure refrigerant temperature is usually controlled to a temperature of about 3 to 4 ° C. in order to prevent frost in the evaporator 8, and the target upper limit temperature of the air blown into the vehicle compartment during cooling is the cooling fee. In order to secure the ring and prevent the bad odor from the evaporator 8, etc., the temperature is usually set to about 12 ° C to 15 °.

Therefore, as the regenerator material, a material having a freezing point located between the low-pressure refrigerant temperature and the target upper limit temperature of the blown air temperature during cooling is preferable. Specifically, the freezing point is 6 ° C.
Paraffin at about 8 ° C is most suitable. Of course, if the low-pressure refrigerant temperature is controlled to 0 ° C. or lower, water (ice) can be used as the cold storage material.

In order to maintain the cold storage state (solidified state) of the regenerator material, it is necessary to maintain the inside of the tank member 11b at a low temperature below the freezing point of the regenerator material.
b must be constructed as an insulating tank. Therefore, as the tank member 11b, a resin tank having an excellent heat insulating property, or a metal tank having a heat insulating material attached to the surface thereof is used.

The cold storage heat exchanger 11 may be constructed as a shell-and-tube type heat exchanger. In that case, the cycle low-pressure refrigerant is passed through the tube arranged inside the shell (tank member), and Inside the shell, the outer space of the tube may be filled with a regenerator material and cooled by the cycle low-pressure refrigerant.

Then, in the cold storage unit 9, the liquid refrigerant tank portion 12 is arranged below the cold storage heat exchanger 11,
The liquid-refrigerant tank section 12 stores the liquid refrigerant condensed in the cold-storage heat exchanger 11 in a cooling / cooling mode (FIG. 6) associated with the stop of a compressor described later. The liquid refrigerant tank unit 1
It is possible to integrally form 2 in the lower part of the tank member 11b of the cold storage heat exchanger 11.

The upper end portion of the liquid refrigerant tank portion 12 is connected to the refrigerant passage 13 between the passage switching valve 10 and the cold storage heat exchanger 11. The lower end portion (bottom portion) of the liquid refrigerant tank portion 12 is connected to an electric pump 14 that serves as liquid refrigerant circulation pump means.

The electric pump 14 sucks the liquid refrigerant in the liquid refrigerant tank portion 12 in the cooling / cooling mode to check the valve 1.
It circulates in a closed circuit from 5 to the flow path switching valve 10 to the evaporator 8 to the cold storage heat exchanger 11 to the liquid refrigerant tank portion 12. That is, in the evaporator 8, the refrigerant always flows in the same direction B both when the compressor is in operation (normal cooling / cooling / cooling) and when the compressor is stopped (in the cooling / cooling mode), which will be described later. .

Here, the electric pump 14 is constituted by, for example, a centrifugal pump using an impeller (impeller). Further, the flow path switching valve 10 is specifically an electric control valve having a rotor type valve body whose rotation angle is controlled by an actuator such as a servomotor, and will be described later by controlling the rotation angle of this valve body. As shown in FIGS. 4 to 6, a three-way valve type flow passage that switches the outlet flow passage of the thermal expansion valve 7 to the inlet side refrigerant flow passage 13 of the cold storage heat exchanger 11 or the check valve 15 side refrigerant flow passage. It performs a switching function.

The outlet refrigerant flow passage 16 of the evaporator 8 is connected to the evaporator outlet refrigerant flow passage 7b inside the expansion valve 7. The refrigerant flow passage 17 of the cold storage heat exchanger 11 is connected in the middle of the outlet refrigerant flow passage 16 of the evaporator 8. The refrigerant passage 17 serves as an outlet-side passage for the cold storage heat exchanger 11 when the compressor is operating, and serves as an inlet-side passage for the cold storage heat exchanger 11 when the compressor is stopped.

Further, the specific refrigerant flow passage in the evaporator 8 is configured as a flow path of the orthogonal / counterflow type illustrated in the above-mentioned FIG. 14, and the refrigerant inlet side heat exchange section 81 shown in FIG.
It is designed to have a larger flow passage cross-sectional area of the refrigerant flow passages 82a and 82b of the refrigerant outlet side heat exchange section 82 than the refrigerant flow passages 81a and 81b. As a result, the increase of the ratio (dryness) of the vapor-phase refrigerant in the outlet-side refrigerant flow paths 82a and 82b of the evaporator 8 → the increase of the pressure loss due to the increase of the refrigerant flow velocity is reduced.

In the example of FIG. 1, the expansion valve 7 is shown separately from the cold storage unit 9, but the expansion valve 7 is also integrated as a part of the cold storage unit 9, and the expansion valve 7 and the cold storage unit 9 are integrated. You may make it mount in a vehicle in the state.

In order to maintain the low temperature state inside the cold storage heat exchanger 11, it is preferable that the cold storage unit 9 suppress heat from entering the cold storage heat exchanger 11 as much as possible. for that purpose,
It is better to install the cool storage unit 9 inside the vehicle, for example, inside the instrument panel at the front of the vehicle. However, when it is not possible to secure a mounting space for the cool storage unit 9 in the passenger compartment due to space restrictions in the passenger compartment, the cool storage unit 9 is placed outside the passenger compartment, for example,
It will be installed in the engine rules etc.

FIG. 3 shows the air conditioning indoor unit 20, and the air conditioning indoor unit 20 is usually mounted inside the instrument panel in the front part of the vehicle interior. The air-conditioning case 21 of the air-conditioning indoor unit 20 constitutes a passage for air blown toward the vehicle interior, and the evaporator 8 is installed in the air-conditioning case 21.

In the air conditioning case 21, a blower 22 is arranged on the upstream side of the evaporator 8, and the blower 22 is provided with a centrifugal blower fan 22a and a drive motor 22b. The inside / outside air switching box 23 is arranged on the suction side of the blower fan 22a, and the inside / outside air switching door 2 in the inside / outside air switching box 23 is disposed.
The outside air (air outside the passenger compartment) or the inside air (air inside the passenger compartment) is switched and introduced by 3a.

In the air conditioning case 21, an air mix door 24 is arranged on the downstream side of the evaporator 8, and hot water (cooling water) of the vehicle engine 4 is arranged on the downstream side of the air mix door 24.
A hot water type heater core 25 that heats air by using as a heat source is installed as a heating heat exchanger.

On the side (upper part) of the hot water heater core 25, there is formed a bypass passage 26 that bypasses the hot water heater core 25 and allows air (cool air) to flow. The air mix door 24 is a rotatable plate-like door, and is for adjusting the air flow rate ratio between the warm air passing through the hot water heater core 25 and the cool air passing through the bypass passage 26. The temperature of the air blown into the passenger compartment is adjusted by adjusting. Therefore, in this example, the air mix door 24 constitutes a temperature adjusting means for the air blown into the vehicle interior.

The hot air from the hot water heater core 25 and the cold air from the bypass passage 26 can be mixed in the air mixing portion 27 to produce air at a desired temperature. Furthermore, in the air conditioning case 21, a blowout mode switching unit is configured on the downstream side of the air mixing unit 27. That is, the defroster opening 28 that blows air to the inner surface of the windshield of the vehicle, and the face opening 2 that blows air toward the upper half of the passenger in the passenger compartment.
9, and the foot opening 30 that blows air toward the feet of the passenger in the passenger compartment is opened and closed by the blowing mode doors 31 to 33.

The temperature sensor 34 of the evaporator 8 is the air conditioning case 2
It is arranged at a portion of the evaporator 8 immediately after the air is blown out, and detects the evaporator blowing temperature Te. Here, the evaporator outlet temperature Te detected by the evaporator temperature sensor 34 is the same as in a normal air conditioner when the electromagnetic clutch 2 of the compressor 1 is controlled to be intermittent or when the compressor 1 is of a variable capacity type. It is used for the discharge capacity control, and the cooling capacity of the evaporator 8 is adjusted by the clutch engagement / disengagement control and the discharge capacity control to control the blowout temperature of the evaporator 8.

In addition to the temperature sensor 34, the air-conditioning control device 5 has an inside air temperature Tr and an outside air temperature T for air-conditioning control.
A detection signal is input from a known sensor group 35 that detects am, the amount of solar radiation Ts, the hot water temperature Tw, and the like. An air conditioning control panel 36 installed near the instrument panel in the passenger compartment has a temperature setting switch manually operated by an occupant, an air volume changeover switch, a blowout mode switch, an inside / outside air changeover switch, and an air conditioner for generating an ON / OFF signal for the compressor 1. Various operation switch groups (not shown) such as switches are provided, and operation signals of these operation switch groups are also input to the air conditioning controller 5.

The air conditioning control device 5 is connected to the engine control device 37, and the engine control device 37 sends the air conditioning control device 5 a rotation speed signal of the vehicle engine 4.
A vehicle speed signal or the like is input. The air-conditioning control device 5 performs predetermined arithmetic processing based on the above various input signals to control the operation of the electromagnetic clutch 2, the flow path switching valve 10, the electric pump 14, and the like.

As is well known, the engine control device 37 comprehensively controls the fuel injection amount to the vehicle engine 4, the ignition timing, etc. based on a signal from a sensor group 38 for detecting the operating condition of the vehicle engine 4. Is. Further, in the eco-run vehicle to which the present embodiment is applied, when the stop state is determined based on the rotation speed signal, the vehicle speed signal, the brake signal, etc. of the vehicle engine 4, the engine control device 37 shuts off the power of the ignition device. The vehicle engine 4 is automatically stopped by stopping fuel injection or the like.

After the engine is stopped, when the vehicle is moved from the stopped state to the starting state by the driver's driving operation, the engine control unit 37 determines the starting state of the vehicle based on the accelerator signal or the like, and the vehicle engine 4 To start automatically. It should be noted that the air-conditioning control device 5 requests the engine restart when the time period of the cooling / cooling mode after the vehicle engine 4 is stopped is long and the cooling due to the amount of cold storage heat of the cold storage heat exchanger 11 cannot be continued. Is output to the engine control device 37.

The air-conditioning control device 5 and the engine control device 37 are composed of a well-known microcomputer including a CPU, a ROM, a RAM and the like, and its peripheral circuits. The air conditioning control device 5 and the engine control device 37 may be integrated as one control device.

Next, the operation of the first embodiment having the above structure will be described. FIG. 4 shows the operation in the normal cooling mode during traveling of the vehicle. In the normal cooling mode, the refrigeration cycle R is operated by driving the compressor 1 by the vehicle engine 4. Therefore, the high-pressure gas-phase refrigerant discharged from the compressor 1 is cooled by the condenser 6 and becomes a supercooled liquid refrigerant and flows into the expansion valve 7. The high-pressure liquid refrigerant is decompressed by the valve portion 7a of the expansion valve 7 to become a low-temperature low-pressure gas-liquid two-phase state.

Here, in the normal cooling mode, the flow passage switching valve 10 shuts off between the outlet flow passage of the expansion valve 7 and the cold storage heat exchanger 11 by the control output of the air conditioning controller 5, and the outlet of the expansion valve 7 is closed. The flow passage is operated to communicate with the flow passage on the electric pump 14 side. At this time, the inflow of the refrigerant into the flow path on the electric pump 14 side is blocked by closing the check valve 15.

Therefore, the entire amount of the low pressure refrigerant that has passed through the expansion valve 7 flows into the evaporator 8 as indicated by the thick arrow in FIG. 4, and the low pressure refrigerant absorbs heat from the blown air in the air conditioning case 21 in the evaporator 8. Evaporate and become a vapor phase refrigerant. This vapor-phase refrigerant is drawn into the compressor 1 through the outlet refrigerant flow path 16 of the evaporator 8 and the evaporator outlet refrigerant flow path 7b inside the expansion valve 7, and is compressed again. The cool air absorbed by the evaporator 8 is blown into the vehicle interior through the face opening 29 or the like to cool the vehicle interior.

Next, when the cooling heat load is reduced to a predetermined amount or less while the vehicle is running, and there is a margin in the cooling capacity,
Alternatively, when the vehicle is decelerated, that is, in a state where the compressor 1 can be driven by the inertial power of the vehicle and the compressor driving power by the vehicle engine 4 can be saved, the air conditioning control device 5
When it is determined in, the normal cooling mode is switched to the cold storage cooling mode.

Here, the state in which the cooling heat load is reduced to a predetermined amount or less can be determined based on, for example, that the evaporator outlet temperature Te has decreased to a predetermined temperature or less.
When the vehicle decelerates, it can be determined based on the vehicle speed and the like.

In the cold storage / cooling mode, the air conditioning controller 5
By the control output of 1, the flow passage switching valve 10 is operated to communicate between the outlet flow passage of the expansion valve 7 and the cold storage heat exchanger 11, as shown in FIG. Therefore, the evaporator 8 and the cold storage heat exchanger 11 are connected in parallel to the outlet passage of the expansion valve 7,
The low-pressure refrigerant that has passed through the expansion valve 7 flows in parallel to the evaporator 8 and the cold storage heat exchanger 11 as indicated by the thick arrow in FIG.

As a result, in the evaporator 8, the low-pressure refrigerant absorbs heat from the air blown in the air-conditioning case 21 and evaporates, so that the air blown is cooled, and the cool air that has passed through the evaporator 8 passes through the face opening 29 or the like from the vehicle. It blows out into the room and cools the passenger compartment. At the same time, the cold storage heat exchanger 11 stores cold in the cold storage material.

That is, when the cooling heat load of the evaporator 8 decreases, the opening degree of the valve portion 7a of the expansion valve 7 decreases, the low-pressure pressure of the refrigeration cycle decreases, and the low-pressure refrigerant temperature changes to the cold-storage heat exchanger 1.
It becomes lower than the freezing point of the cold storage material of No. 1. Therefore,
In the cold storage heat exchanger 11, solidification of the cold storage material is started by evaporation of the low-pressure refrigerant, and latent heat of solidification is stored in the cold storage material.
Then, the vapor-phase refrigerant evaporated in the evaporator 8 and the cold storage heat exchanger 11 is the outlet refrigerant flow path 16 of the evaporator 8 and the expansion valve 7.
It is sucked into the compressor 1 through the evaporator outlet refrigerant flow path 7b and is compressed again.

By the way, the liquid refrigerant tank portion 12 includes the refrigerant passage 13 on the inlet side of the cold storage heat exchanger 11 and the cold storage heat exchanger 1.
Since it is arranged at a position lower than 1, a part of the liquid refrigerant in the gas-liquid two-phase low-pressure refrigerant flowing from the refrigerant flow path 13 into the cold storage heat exchanger 11 in the cold storage cooling mode is the gas phase refrigerant. They are separated due to the difference in density and accumulated in the liquid refrigerant tank portion 12.

Next, description will be made regarding a case where the vehicle engine 4 is automatically stopped when the vehicle is stopped such as waiting for a signal. Even when the vehicle engine 4 is stopped while the air conditioning is in operation (the blower 22 is in operation). As a result, the compressor 1 of the refrigeration cycle R is forcibly stopped. Therefore, the air conditioning control device 5 determines the vehicle engine (compressor) stop state when the vehicle is stopped, and as shown in FIG. 6, the flow path switching valve 10 is in the normal cooling mode by the control output of the air conditioning control device 5. It is operated in the same state as.

That is, the flow passage switching valve 10 shuts off the cold storage heat exchanger 11 from the outlet flow passage of the expansion valve 7, and the expansion valve 7
The outlet flow passage is operated to communicate with the flow passage on the electric pump 14 side. Moreover, the electric power is supplied to the electric pump 14 in the cold storage unit 9 by the control output of the air conditioning control device 5 to operate the electric pump 14.

As a result, in the refrigeration cycle R, as shown by the thick arrow in FIG. 6, the liquid refrigerant tank portion 12 → the electric pump 14 → the check valve 15 → the flow path switching valve 10 → the evaporator 8 → the refrigerant flow path 16, 17 → Cold heat exchanger 11 → Liquid refrigerant tank unit 12
And a liquid refrigerant in the liquid refrigerant tank portion 12 is introduced into the evaporator 8.

Therefore, in the evaporator 8, the liquid refrigerant tank portion 12
Since the liquid refrigerant from (1) absorbs heat from the blown air of the blower 22 and evaporates, the cooling action of the evaporator 8 can be continued even after the compressor is stopped, and the cooling action of the vehicle interior can be continued. Evaporator 8
Since the temperature of the vapor-phase refrigerant vaporized at is higher than the freezing point of the regenerator material of the regenerator 11, the regenerator material absorbs latent heat of fusion from the vapor-phase refrigerant and changes (melts) from the solid phase to the liquid phase. As a result, the vapor phase refrigerant is cooled and liquefied by the regenerator material. The liquid refrigerant falls due to gravity and is stored in the liquid refrigerant tank portion 12.

As the regenerator material changes to the liquid phase, the amount of the liquid refrigerant in the liquid refrigerant tank portion 12 gradually decreases, but the liquid refrigerant in the liquid refrigerant tank portion 12 remains. While the vehicle is stopped, the vehicle interior cooling function can be continued when the vehicle is stopped (when the compressor is stopped).

The stop time for waiting for a signal is usually 1
Since it is a short time of about 2 minutes, paraffin with a freezing point = 6 ° C. and latent heat of solidification = 229 kJ / kg is used as a cold storage material.
It has been confirmed that by using about 420 g, the vehicle interior cooling function can be continued while the vehicle is stopped for about 1 to 2 minutes.

By the way, as shown in FIGS. 4 to 6, in any of the normal cooling mode, the cold storage cooling mode, and the free-cooling cooling mode, the refrigerant flow direction in the evaporator 8 is
It is the same direction B from the outlet passage of the expansion valve 7 toward the evaporator outlet passage 16. Therefore, the heat exchange performance of the evaporator 8 in the cooling / cooling mode due to the stop of the compressor can be satisfactorily exhibited as in the compressor operation.

The following is a specific description of this.
In the refrigeration cycle R of the embodiment, the thermal expansion valve 7 is used as a pressure reducing device, and the thermal expansion valve 7 adjusts the cycle circulation refrigerant flow rate so that the evaporator outlet refrigerant has a predetermined superheat degree. Therefore, in the evaporator 8, a refrigerant superheat region is formed in the refrigerant outlet side region thereof, and the outlet side refrigerant temperature of the evaporator 8 becomes higher than the inlet side refrigerant temperature.

Therefore, as shown in FIG. 14, by forming a counterflow refrigerant passage in the air flow direction A, air is exchanged with air in both the refrigerant inlet side heat exchange section 81 and the refrigerant outlet side heat exchange section 82. The heat exchange performance of the evaporator 8 can be improved by increasing the temperature difference with the refrigerant.

Further, in the refrigerant flow path configuration of the evaporator 8, the evaporation of the refrigerant gradually progresses from the refrigerant inlet side to the refrigerant outlet side, and the ratio (dryness) of the vapor phase refrigerant increases, so that the refrigerant outlet side The increase in pressure loss due to the increase in the flow velocity of the refrigerant becomes remarkable in the flow passage. Therefore, in the evaporator 8 of the first embodiment, the refrigerant flow paths 81a and 81b of the refrigerant inlet side heat exchange section 81 are provided.
The refrigerant flow path 82a of the refrigerant outlet side heat exchange section 82,
The increase in pressure loss is reduced by designing the flow passage cross-sectional area of 82b to be large.

Since all the refrigerant flow directions in the evaporator 8 in the above three cooling modes are the same direction B, the effect of improving heat exchange performance by the counter flow and the pressure loss in the refrigerant outlet side passages 82a, 82b are obtained. The effect of reducing the increase can be exhibited in the cooling / cooling mode as in the other modes.

In the prior art of FIG. 13, the operation of the centrifugal electric pump 42 in the cooling / cooling mode causes the cold storage heat exchanger 40 → the electric pump 42 → the solenoid valve 41 → the storage tank 43 → the evaporator 8 to operate. If the refrigerant is circulated in the same direction, it becomes possible to flow the refrigerant in the evaporator 8 in the same direction as when the compressor is operating, even in the cooling / cooling mode. However, with this configuration, the refrigerant flows through the pump mechanism portion of the electric pump 42 in the direction opposite to the normal refrigerant flow direction during the cold storage / cooling mode,
Since the refrigerant flows to the cold storage heat exchanger 40 through the electric pump 42, the flow of the refrigerant to the cold storage heat exchanger 40 is significantly limited by the pump mechanism portion of the electric pump 42. As a result, the flow rate of the refrigerant to the cold storage heat exchanger 11 is reduced and the cold storage capacity of the cold storage heat exchanger 40 is extremely reduced, so such a measure cannot be actually adopted.

On the other hand, according to the first embodiment, in the cold storage / cooling mode, the refrigerant flows from the flow path switching valve 10 through the refrigerant flow path 13 to the cold storage heat exchanger 11, and bypasses the electric pump 42 to carry the refrigerant. The flow rate of the refrigerant to the cold storage heat exchanger 11 never decreases due to the presence of the electric pump 42.

In the first embodiment, the refrigerant is prevented from flowing to the cold storage heat exchanger 11 through the flow path switching valve 10, the electric pump 14 and the liquid refrigerant tank portion 12 in the normal cooling mode of FIG. The check valve 15 is used to
In the normal cooling mode, the check valve 15 can be omitted if the flow resistance of the electric pump 14 itself in the stopped state can restrict the refrigerant flow into the cold storage heat exchanger 11 to a small amount.

Further, the function of the check valve 15 is changed to the flow path switching valve 10
May be integrated with. That is, the flow path switching valve 10 is
(1) In the normal cooling mode, both the flow paths on the side of the cold storage heat exchanger 11 and the electric pump 14 are shut off, and (2) at the time of the cold storage cooling mode, only the flow path on the side of the cold storage heat exchanger 11 is in communication, and the electric pump The flow path on the 14 side is shut off,
(3) In the cooling / cooling mode, only the flow path on the electric pump 14 side may be in the communication state, and the flow path on the cold storage heat exchanger 11 side may be in the cutoff state.

(Second Embodiment) In the above-described first embodiment, the flow path on the cold storage heat exchanger 11 side is connected in parallel to the refrigerant flow path of the evaporator 8 in the cold storage cooling mode to cool the evaporator 8 and the cold storage. The refrigerant is configured to flow in parallel with the heat exchanger 11. However, in the second embodiment, the cold storage heat exchanger 11 is arranged in series in the refrigerant passage on the inlet side of the evaporator 8 and the cold storage is performed during operation of the compressor. Refrigerant is always allowed to flow in the serial flow path of the heat exchanger 11 and the evaporator 8, whereby the flow path switching valve 1 of the first embodiment is provided.
Abolish 0.

FIG. 7 shows the state of the normal cooling / cooling storage mode according to the second embodiment, and FIG. 8 shows the state of the standing cooling / cooling mode according to the second embodiment. In the second embodiment, since the refrigerant always flows through the series flow path of the cold storage heat exchanger 11 and the evaporator 8 when the compressor is operating, the normal cooling mode in which the normal cooling mode and the cold storage cooling mode of the first embodiment are combined.・ Only the cold storage mode is set.

7 and 8, the same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. Only the different points will be specifically described below. The cold storage heat exchanger 11 is arranged in the inlet side refrigerant flow path 18 of the evaporator 8 connected to the outlet portion of the valve 7a of the expansion valve 7, and the cold storage heat exchanger 11 is connected to the evaporator via the first check valve 15a. It is connected to the entrance of 8. Then, the liquid refrigerant tank portion 1 arranged below the cold storage heat exchanger 11
2 and the electric pump 14 are provided in parallel with the first check valve 15a.

Here, the electric pump 14 is configured to suck the liquid refrigerant in the liquid refrigerant tank portion 12 and discharge it toward the inlet portion of the evaporator 8. The first check valve 15a closes when the electric pump 14 operates, and blocks the pump discharge refrigerant from directly flowing toward the liquid refrigerant tank portion 12 side.

On the other hand, the outlet refrigerant flow passage 16 of the evaporator 8 is connected to the evaporator outlet refrigerant flow passage 7b in the expansion valve 7, and passes through the refrigerant return flow passage 19 to the refrigerant inlet side of the cold storage heat exchanger 11. Connected. A second check valve 15b is provided in the refrigerant return passage 19, and the expansion valve 7 is provided by the second check valve 15b.
The outlet refrigerant is prevented from directly going to the outlet refrigerant passage 16 of the evaporator 8.

Next, the operation of the second embodiment will be described. FIG. 7 shows the operation in the normal cooling / cooling storage mode while the vehicle is running. In this normal cooling / cooling storage mode, the refrigeration cycle R is operated by driving the compressor 1 by the vehicle engine 4. As indicated by the thick arrow, the low-pressure refrigerant after passing through the expansion valve 7 always flows in the series flow path of the cold storage heat exchanger 11 and the evaporator 8.

Therefore, the cold storage material in the cold storage heat exchanger 11 is first cooled by the low-temperature low-pressure refrigerant after passing through the expansion valve 7, and the cold storage material stores cold energy. Then, the low-pressure refrigerant that has passed through the cold storage heat exchanger 11 then absorbs heat from the blown air in the air conditioning case 21 in the evaporator 8 and evaporates to become a vapor-phase refrigerant. This vapor-phase refrigerant is used in the outlet refrigerant flow path 16 of the evaporator 8 and the expansion valve 7.
It is sucked into the compressor 1 through the evaporator outlet refrigerant flow path 7b and is compressed again. The cool air cooled by the evaporator 8 is blown into the vehicle compartment through the face opening 29 or the like to cool the vehicle compartment. Note that a part of the liquid refrigerant in the low-pressure refrigerant that has passed through the cold storage heat exchanger 11 is collected in the lower liquid refrigerant tank portion 12 by gravity.

In the normal cooling / cooling storage mode, since the operation of the electric pump 14 for circulating the liquid refrigerant is unnecessary, the electric pump 14 is stopped by the output of the air conditioning controller 5. Therefore, since the electric pump 14 becomes a flow resistance, the amount of the liquid refrigerant in the liquid refrigerant tank portion 12 flowing into the inlet side of the evaporator 8 via the electric pump 14 is small.

Next, the behavior of the refrigerant in the cold storage unit 9 in the normal cooling / cooling mode will be described more specifically. When the cooling operation is started at the high outside air temperature in summer, the intake air temperature of the evaporator 8 is The temperature becomes as high as 40 ° C. or more, and the cooling heat load on the evaporator 8 becomes very large. Under such a cooling high load condition, the superheat degree of the outlet refrigerant of the evaporator 8 becomes excessive, the opening of the valve portion 7a of the expansion valve 7 is fully opened, and the low pressure of the refrigeration cycle rises.

Therefore, the temperature of the low-pressure refrigerant flowing into the cold storage heat exchanger 11 of the cold storage unit 9 becomes higher than the freezing point (about 6 to 8 ° C.) of the cold storage material of the cold storage heat exchanger 11. Therefore, the regenerator material does not solidify due to heat exchange with the low-pressure refrigerant, and only absorbs sensible heat from the regenerator material. As a result, the amount of heat absorbed by the low-pressure refrigerant in the cold-storage heat exchanger 11 is very small under the cooling high-load condition. Therefore, most of the low-pressure refrigerant absorbs heat from the air blown into the passenger compartment in the evaporator 8 and evaporates, as in an ordinary air conditioner that does not have the cold storage heat exchanger 11.

When the cooling load is high, the inside air mode for sucking the inside air from the inside / outside air switching box 23 shown in FIG. 3 is usually selected. Therefore, the intake air temperature of the evaporator 8 decreases with the lapse of time after the start of cooling. , Cooling heat load decreases. As a result, the degree of superheat of the outlet refrigerant of the evaporator 8 is reduced, the opening degree of the valve portion 7a of the expansion valve 7 is reduced, the low pressure of the refrigeration cycle is reduced, and the low pressure refrigerant temperature is reduced.

The low-pressure refrigerant temperature changes to the cold storage heat exchanger 11
When the temperature is lower than the freezing point of the cold storage material, solidification of the cold storage material is started and the low-pressure refrigerant absorbs latent heat of solidification from the cold storage material.
The amount of heat absorbed from the cold storage material increases. However, at the time when the cold storage material reaches the stage of storing the latent heat of solidification in this way, the low-pressure refrigerant temperature has already sufficiently decreased due to the reduction of the cooling heat load, and the air blown into the vehicle compartment has already sufficiently decreased.

Therefore, the rapid cooling performance (cool down performance) under the cooling high load condition is not significantly hindered by the cold storage action of the solidification latent heat on the cold storage material. In other words, the cold storage heat exchanger 11 is connected in series to the refrigerant circuit of the cooling evaporator 8, and even if the low-pressure refrigerant always flows through the cold storage heat exchanger 11, the rapid cooling performance under the cooling high load condition is slightly reduced. Only, and can be demonstrated well.

Next, description will be made regarding a case where the vehicle engine 4 is automatically stopped when the vehicle is stopped such as waiting for a signal. Even when the vehicle engine 4 is stopped while the air conditioning is in operation (the blower 22 is in operation). As a result, the compressor 1 of the refrigeration cycle R is forcibly stopped. Therefore, the air conditioning control device 5 determines the vehicle engine (compressor) stop state when the vehicle is stopped, supplies power to the electric pump 14 in the cold storage unit 9, and operates the electric pump 14.

As a result, the liquid refrigerant accumulated in the liquid refrigerant tank portion 12 below the cold storage heat exchanger 11 is transferred to the electric pump 1
4 inhales and discharges the liquid refrigerant toward the inlet side of the evaporator 8. Due to the suction and discharge actions of the liquid refrigerant by the electric pump 14, the refrigerant pressure acts on the first check valve 15a in the opposite direction, and the first check valve 15a is closed. Contrary to this,
The refrigerant pressure acts on the second check valve 15b in the forward direction, and
The check valve 15b opens.

Therefore, as indicated by the thick arrow in FIG.
Liquid refrigerant tank portion 12 → electric pump 14 → evaporator 8 → outlet refrigerant flow path 16 → refrigerant return flow path 19 → second check valve 15b →
Refrigerant circulates in the refrigerant circulation circuit composed of the cold storage heat exchanger 11 → the liquid refrigerant tank portion 12.

Therefore, in the evaporator 8, the liquid refrigerant tank portion 12
Since the liquid refrigerant from (1) absorbs heat from the blown air of the blower 22 and evaporates, the cooling action of the evaporator 8 can be continued even after the compressor is stopped, and the cooling action of the vehicle interior can be continued.

The vapor-phase refrigerant evaporated in the evaporator 8 is cooled and condensed by the latent heat of fusion of the cold storage material when passing through the cold storage heat exchanger 11. The liquid refrigerant falls due to gravity and is stored in the liquid refrigerant tank portion 12.

Then, the regenerator material absorbs latent heat of solidification from the vapor phase refrigerant and changes its phase to the liquid phase, whereby the amount of the liquid refrigerant in the liquid refrigerant tank section 12 decreases, but the liquid refrigerant tank section While the liquid refrigerant in 12 remains, the vehicle interior cooling operation at the time of vehicle stop (when the compressor is stopped) can be continued.

By the way, in the second embodiment as well, the refrigerant flows in the same direction B in the evaporator 8 in both the normal cooling / cooling mode and the cold cooling / cooling mode. The heat exchange performance of the vessel 8 can always be maintained in a good state.

Further, unlike the first embodiment, the second embodiment has a configuration in which the cool storage heat exchanger 11 is connected in series to the cooling evaporator 8, so that the second embodiment will be described next.
The advantages of the configuration unique to the embodiment will be described in detail by comparison with the first embodiment. In the first embodiment, in the air conditioning refrigeration cycle R, the cool storage heat exchanger 11 having a built-in cool storage material is used for the cooling evaporator 8 with respect to the refrigerant flow when the compressor is operating.
Since it is provided in parallel with the above, it is essential to switch the refrigerant flow path of the cold storage heat exchanger 11 by the flow path switching valve 10 according to the operating condition of the refrigeration cycle. This also applies to the above-mentioned conventional technique (Japanese Patent Laid-Open No. 2000-313226).

Contrary to this, according to the present embodiment, since the cold storage heat exchanger 11 is connected in series to the cooling evaporator 8, the condition that the cooling heat load is very high as in the start of cooling in the summer. Also in the above, since the entire amount of the cycle circulating refrigerant flow passes through the cooling evaporator 8, the addition of the cold storage heat exchanger 11 does not reduce the circulating refrigerant flow rate to the cooling evaporator 8.

Moreover, the freezing point of the cold storage material in the cold storage heat exchanger 11 is set to a temperature (about 6 to 8 ° C.) lower than the target upper limit temperature (about 12 to 15 ° C.) of the blown air temperature during cooling as described above. As a result, the freezing point of the cold storage material becomes lower than the temperature of the low-pressure refrigerant under the cooling high heat load condition. Therefore, under the cooling high heat load condition, the regenerator material does not solidify due to heat exchange with the low-pressure refrigerant, and only a slight amount of sensible heat is absorbed.

Therefore, most of the low-pressure refrigerant absorbs heat from the air blown into the passenger compartment in the evaporator 8 and evaporates, as in the case of a normal air conditioner without the cold storage heat exchanger 11. That is, the evaporator 8 for cooling under the high heat load condition for cooling is performed without performing a special operation for switching the flow of the refrigerant to the cold storage heat exchanger 11.
The maximum cooling capacity of can be exhibited well.

When the cold storage material in the cold storage heat exchanger 11 is solidified and the cold storage is completed, the cold storage heat exchanger 1
Although the heat absorption of the low-pressure refrigerant in 1 is almost eliminated, the expansion valve 7 senses the degree of superheat of the refrigerant at the outlet of the evaporator 8 because the cold storage heat exchanger 11 is arranged at the inlet side of the cooling evaporator 8. The flow rate can be adjusted. Therefore, even after the cold storage is completed, an appropriate refrigerant flow rate according to the cooling heat load of the evaporator 8 can be supplied to the evaporator 8.

FIG. 9 shows a comparative example of the second embodiment. If the cold storage heat exchanger 11 is arranged in the outlet side refrigerant passage 16 of the evaporator 8 as in this comparative example, the evaporator 8 Even if the outlet refrigerant has a superheat degree, the outlet refrigerant of the evaporator 8 is cooled by the cool storage material and the superheat degree becomes small in a state where the cool storage material has completed the cold storage (solidification). As a result, the opening degree of the expansion valve 7 decreases, and the refrigerant flow rate becomes too small with respect to the cooling heat load of the evaporator 8. On the other hand, in the second embodiment, such a problem does not occur by disposing the cold storage heat exchanger 11 on the inlet side of the cooling evaporator 8.

(Third Embodiment) In the above first and second embodiments, the refrigeration cycle in which the expansion valve 7 is used as the pressure reducing means and the expansion valve 7 adjusts the superheat degree of the refrigerant exiting the evaporator 8 has been described. However, in the second embodiment, an accumulator is arranged on the outlet side of the evaporator 8 (the suction side of the compressor 1), and in this accumulator, the vapor-liquid of the evaporator outlet refrigerant is separated to collect the liquid refrigerant, and the vapor-phase refrigerant. The cold-storage heat exchanger 11 is combined with an accumulator-type refrigeration cycle that allows the compressor 1 to be sucked into the compressor 1.

FIGS. 10 and 11 show the third embodiment, and the same parts as those of the first and second embodiments are designated by the same reference numerals and the description thereof will be omitted. In addition, since the electric control units such as the control devices 5 and 37 are the same as those in the first and second embodiments,
0 and FIG. 11, the illustration of the electric control unit is omitted.

In the accumulator type refrigeration cycle, the accumulator tank 120 is arranged on the outlet side of the evaporator 8. Therefore, in the third embodiment, the regenerator unit 9 is constructed integrally with the accumulator tank 120 by paying attention to the accumulator tank 120. To do.

That is, in the third embodiment, the cold storage heat exchanger 11 of the cold storage unit 9 is arranged in the outlet side refrigerant flow path of the evaporator 8, and the tank member 11b of the cold storage heat exchanger 11 is connected to the accumulator tank 120. It is integrally configured on the upper side. Therefore, the accumulator tank 120 also serves as the liquid refrigerant tank portion 12 of the first and second embodiments.

The inside of the accumulator tank 120 is U
The outlet pipe 121 formed in a bent shape is arranged, and an oil return hole (not shown) is opened at the U-shaped bottom portion of the outlet pipe 121, and the oil return hole is used for lubricating the compressor contained in the liquid refrigerant. It is designed to suck in oil. In addition, the gas-phase refrigerant suction port 1 is provided at the U-shaped one end of the outlet pipe 121.
21a is provided, and this gas-phase refrigerant inlet 121a is opened in the space above the liquid refrigerant accumulated in the lower part of the accumulator tank 120, whereby the accumulator tank 1
The gas-phase refrigerant in the upper part of 20 is sucked into the outlet pipe 121 from the suction port 121a. Outlet pipe 1
The other end side of 21 is taken out from the upper surface of the accumulator tank 120 to the outside of the tank and connected to the suction side of the compressor 1.

A refrigerant return passage 19 is provided which connects the bottom surface of the accumulator tank 120 and the inlet side passage of the evaporator 8, and the refrigerant return passage 19 has an electric pump 14 for circulating liquid refrigerant and The check valve 15b is arranged so that the liquid refrigerant in the accumulator tank 120 is sucked by the electric pump 14 and discharged toward the inlet side of the evaporator 8. The check valve 15b is similar to the second check valve 15b in FIGS. 7 to 9.

The third embodiment relates to an accumulator type refrigeration cycle, in which the vapor-liquid of the evaporator outlet refrigerant is separated in the accumulator tank 120 to store the liquid refrigerant. Then, the gas-phase refrigerant can be sucked from the gas-phase refrigerant suction port 121 a of the outlet pipe 121 and sent to the suction side of the compressor 1.

Therefore, the liquid refrigerant compression of the compressor 1 can be prevented without adjusting the superheat degree of the refrigerant at the evaporator outlet.
In the third embodiment, as the decompression device 70, a capillary tube, a fixed throttle such as an orifice, or a variable throttle that responds to the high pressure of the refrigerant can be used. These decompression devices 70 are temperature type expansion valves 7 having a superheat control mechanism.
The configuration is simpler and less expensive than the.

FIG. 10 shows a normal cooling / cooling mode when the vehicle is running according to the third embodiment. When the compressor 1 is driven by the vehicle engine 4, the circuit shown by the thick arrow in FIG. 10, that is, the compressor. Refrigerant circulates in the circuit from the discharge side of 1 to the condenser 6 to the decompression device 70 to the evaporator 8 to the cold storage heat exchanger 11 to the accumulator tank 120 to the suction side of the compressor 1, and the low pressure refrigerant in the evaporator 8 The heat is absorbed from the blown air in the air conditioning case 21 to evaporate, whereby the blown air is cooled and the vehicle interior can be cooled.

Further, in the cold storage heat exchanger 11, the cold storage material is cooled and solidified by the low-pressure refrigerant to perform cold storage in the cold storage material. In the normal cooling / cooling storage mode, the electric pump 14 is stopped as in the first and second embodiments, and the check valve 15b is closed.

FIG. 11 shows a cooling / cooling mode when the vehicle is stopped according to the third embodiment. At this time, the electric pump 14 is operated and the refrigerant is circulated by the circuit shown by the thick arrow in FIG. That is, by sucking and discharging the liquid refrigerant in the accumulator tank 120 with the electric pump 14, the electric pump 14 → the check valve 15b (open valve state) → the evaporator 8 → the cold storage heat exchanger 11 → the accumulator tank 120. Refrigerant circulates in every circuit.

Thus, the accumulator tank 120
The stored liquid refrigerant therein is circulated to the evaporator 8, and the vapor-phase refrigerant evaporated in the evaporator 8 is cooled by the cold storage heat exchanger 11.
By liquefying, even in the third embodiment, the function of leaving and cooling air when the vehicle is stopped can be exhibited well.

By the way, since the third embodiment is an accumulator type refrigeration cycle, the cold storage heat exchanger 11 is connected in series to the outlet side of the evaporator 8. This is for the following reason. That is, in the accumulator type refrigeration cycle,
The decompression device 70 can be configured by a capillary tube, a fixed throttle such as an orifice, or a variable throttle that responds to the pressure of high-pressure refrigerant, and it is not necessary to use the expansion valve 7. Therefore, even if the cold storage heat exchanger 11 is connected in series to the outlet side of the evaporator 8, the above-mentioned problem of adjusting the superheat degree of the refrigerant at the outlet of the evaporator does not occur.

Since a pressure loss is always generated in the refrigerant flow flowing through the refrigerant passage of the evaporator 8, the refrigerant pressure (evaporation pressure) on the outlet side of the evaporator 8 is lower than that on the outlet side. . Here, in the accumulator type refrigeration cycle, since the gas-liquid interface of the refrigerant is formed inside the accumulator tank 120 and the refrigerant is saturated, the refrigerant in the evaporator 8 does not become overheated. Therefore, the refrigerant temperature (evaporation temperature) on the outlet side of the evaporator 8 is always lower than that on the inlet side as the refrigerant pressure decreases.

Therefore, in the accumulator type refrigeration cycle, by connecting the cold storage heat exchanger 11 in series to the outlet side of the evaporator 8, the cold storage material can be cooled by a lower temperature refrigerant, and the temperature of the cold storage material and the refrigerant can be reduced. The difference can be enlarged to improve the heat exchange efficiency, and the solidification of the regenerator material can be completed in a shorter time.

Incidentally, FIG. 12 is a comparative example of the third embodiment, and since the cold storage heat exchanger 11 is connected in series to the inlet side of the evaporator 8, the temperature of the low pressure refrigerant for cooling the cold storage material is the third.
It becomes higher than that of the embodiment, and the cooling capacity of the regenerator material becomes lower than that of the third embodiment.

Since the third embodiment is an accumulator type refrigeration cycle in which the temperature of the refrigerant on the outlet side is lower than the temperature of the refrigerant on the outlet side in the evaporator 8, the structure of the refrigerant flow path in the evaporator 8 is as shown in FIG. It is not a counter flow of 14 but a parallel flow. That is, in FIG. 14, the refrigerant inlet side heat exchange section 81 is arranged on the windward side in the air flow direction A, and the refrigerant outlet side heat exchange section 82 is arranged on the leeward side in the air flow direction A. Thereby, in the evaporator 8 of the accumulator type refrigeration cycle, the temperature difference between the air and the refrigerant can be increased in both the refrigerant inlet side heat exchange section 81 and the refrigerant outlet side heat exchange section 82, and the heat exchange performance can be improved.

Also in the third embodiment, since the refrigerant flows in the same direction B in the evaporator 8 in both the normal cooling / cooling mode and the cold cooling / cooling mode, it is different from the first and second embodiments. Similarly, the heat exchange performance of the evaporator 8 can always be maintained in a good state.

In the third embodiment, the check valve 15b
Is to prevent the low-pressure refrigerant on the outlet side of the pressure reducing device 70 from flowing into the accumulator tank 120 through the refrigerant return passage 19 by closing the valve when the electric pump 14 is stopped, that is, in the normal cooling / cooling mode. Therefore, the check valve 15b may be omitted as long as the flow resistance of the electric pump 14 itself when stopped can reduce the flow of the low-pressure refrigerant to a level at which there is no practical problem.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a refrigeration cycle showing a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating the regenerator material container of FIG.

FIG. 3 is a schematic cross-sectional view of an air conditioning indoor unit portion according to the first embodiment.

FIG. 4 is a circuit diagram for explaining an operation in a normal cooling mode according to the first embodiment.

FIG. 5 is a circuit diagram for explaining an operation in the cold storage cooling mode according to the first embodiment.

FIG. 6 is a circuit diagram for explaining an operation in a cooling / cooling mode according to the first embodiment.

FIG. 7 is a circuit diagram for explaining an operation in a normal cooling / cooling storage mode according to a second embodiment.

FIG. 8 is a circuit diagram for explaining an operation in a cooling and cooling mode according to a second embodiment.

FIG. 9 is a circuit diagram for explaining an operation in a normal cooling / cooling storage mode according to a comparative example of the second embodiment.

FIG. 10 is a circuit diagram for explaining an operation in a normal cooling / cooling storage mode according to a third embodiment.

FIG. 11 is a circuit diagram for explaining an operation in a cooling / cooling mode according to a third embodiment.

FIG. 12 is a circuit diagram for explaining an operation in a normal cooling / cooling storage mode according to a comparative example of the third embodiment.

FIG. 13 is a circuit diagram of a refrigeration cycle of a conventional device.

FIG. 14 is a schematic explanatory diagram of a refrigerant channel of an evaporator used in a conventional device and the first and second embodiments of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor, 4 ... Vehicle engine, 6 ... Condenser (high pressure side heat exchanger), 7 ... Expansion valve (pressure reducing means), 70 ... Pressure reducing device (pressure reducing means) such as fixed throttle, 8 ... Evaporator, 9 ... Cool storage unit, 10 ... Tank member, 11 ... Cool storage heat exchanger, 11a ...
Cooling material container, 15 ... Electric pump.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F25B 5/00 F25B 5/00 A 43/00 43/00 E

Claims (7)

[Claims] 1. A vehicle engine (4) at least when the vehicle is stopped.
A vehicle air conditioner mounted on a vehicle for performing control for stopping a compressor, the compressor (1) driven by the vehicle engine (4).
A high pressure side heat exchanger (6) for radiating heat of the high pressure refrigerant discharged from the compressor (1), and a decompression means (7, 70) for decompressing the refrigerant having passed through the high pressure side heat exchanger (6). ), An evaporator (8) for evaporating the low-pressure refrigerant decompressed by the decompression means (7, 70) to cool the air blown into the passenger compartment, and the low-pressure refrigerant when the compressor (1) is in operation. Storage heat exchanger (11) having a storage material (11a) cooled by
Pump means for circulating a refrigerant between the evaporator (8) and the cold storage heat exchanger (11) when the vehicle engine (4) stops and the compressor (1) stops. 14), when the compressor (1) is stopped, the vapor-phase refrigerant evaporated in the evaporator (8) is cooled and condensed by the cold storage heat of the cold storage material (11a), and the condensed liquid refrigerant is provided. The evaporator (8)
And the flow direction of the refrigerant to the evaporator (8) when the compressor (1) is stopped is the same as the flow direction of the refrigerant to the evaporator (8) when the compressor (1) is in operation. A vehicle air conditioner characterized by the above. 2. The cold storage heat exchanger (11) is connected in parallel with the evaporator (8) with respect to the flow of refrigerant during operation of the compressor (1). Air conditioning system for vehicles. 3. The cold storage heat exchanger (11) according to claim 1, characterized in that it is connected in series with the evaporator (8) with respect to the flow of refrigerant during operation of the compressor (1). Air conditioning system for vehicles. 4. The decompression means is an expansion valve (7) for adjusting the refrigerant flow rate according to the degree of superheat of the outlet refrigerant of the evaporator (8), and the cold storage heat exchanger (11) is connected to the evaporator. The vehicle air conditioner according to claim 3, wherein the air conditioner is provided on the refrigerant inlet side of (8). 5. An accumulator tank (120) arranged on a refrigerant outlet side of the evaporator (8), wherein a gas-liquid of a low pressure refrigerant at an outlet of the evaporator (8) is provided inside the accumulator tank (120). And the gas-phase refrigerant is led to the suction side of the compressor (1). The cold storage heat exchanger (11) is connected to the refrigerant outlet side of the evaporator (8) and the accumulator tank. (120) provided between the cold storage heat exchanger (11) and the compressor (1) during operation.
The low-pressure refrigerant passing through the accumulator tank (12
0) It passes through the inside and is sucked into the compressor (1), and when the compressor (1) is stopped, the liquid refrigerant in the accumulator tank (120) is evaporated by the pump means (14). The vehicle air conditioner according to claim 1, wherein the air conditioner is installed in the device (8). 6. The vehicle air conditioner according to claim 5, wherein the pressure reducing means (70) is composed of a fixed throttle or a variable throttle that responds to a high-pressure refrigerant state. 7. The low-pressure refrigerant bypasses the pump means (14) and flows into the cold storage heat exchanger (11) when the compressor (1) is in operation. Item 7. The vehicle air conditioner according to any one of items 1 to 6.